Advance Magazine - Winter 2004/2005

O F F I C I A L P U B L I C AT I O N O F T H E A DVA N C E D F O O D S A N D M AT E R I A L S N E T WO R K

Volume I Number 1 Winter 2004/05

Amyl Ghanem, Michael Nickersonand Allan Paulson from DalhousieUniversity are developing new gelsthat could have wide-ranging applications, including human medicine.

A g e l t o m a ke yo u we l l . . . page 14

2 AFMNet – ADVANCE / 2004

Volume I Number 1 Winter 2004/05

The official publication of the AdvancedFoods and Materials Network

A publication to promote dialogue andunderstanding about sophisticated foodsand materials research across Canada.

Executive EditorsRickey Yada

Allan Paulson

EditorsOwen RobertsMarianne Clark

Associate EditorMurray Tong

Project Co-ordinatorKate Roberts

Copy EditorBarbara Chance

DesignJnD Marketing

Financial ManagerAndrew Pulcins

Address correspondence to:Kate Roberts, Communications Officer

150 Research Lane, Suite 215Guelph, Ontario, Canada N1G 4T2

Phone: 519-822-6253 Fax: 519-824-8453

E-mail: [email protected]

Visit the AFMNet website:www.afmnet.ca

This publication was written by students inthe SPARK program — an acronym for

Students Promoting Awareness of ResearchKnowledge — at the University of Guelph

in Ontario, Canada.

For address changes, please contact:Laurel Marshall, Administrative Officer

150 Research Lane, Suite 215Guelph, Ontario, Canada N1G 4T2E-mail: [email protected]

Watch for the online edition of Advance,available in French and English, at

www.afmnet.ca/Publications/ResearchMagazine/French/Advance.pdf

La publication Advance sera disponible bientôt,en anglais et en français, sur le site Web

www.afmnet.ca/Publications/ResearchMagazine/French/Advance.pdf

Welcome to the premier edition of Advance, a publication designed to helpcommunicate about the exciting activities and accomplishments that are part ofCanada’s new Advanced Foods and Materials Network (AFMNet).

AFMNet is part of the federal Networks of Centres of Excellence (NCE)program, which helps support unique partnerships between universities, industry, government and not-for-profit organizations. Across Canada 21 networks exist, driven by a common commitment to transform research andentrepreneurial talent into economic and social benefits for all Canadians.

AFMNet focuses on food and materials research related to renewable agricultural commodities such as wheat, conifer trees, canola, flax and sunflowers. These commodities promise to impact on the economy and healthof Canadians, through their consumption or application. The diversity ofAFMNet research means the network has the capacity to examine the ethical,legal and safety implications associated with new products and technologies.

And while commodities are central to our research, people are our mostvaluable resource. A major strength of AFMNet is the people we’re training,from undergraduate students to visiting scientists. Our trainees will have anopportunity to visit and study in numerous laboratories and facilities and obtaina truly multi-disciplinary experience.

Theirs are stories you’ll read about in Advance, as we endeavour to publi-cally and understandably communicate about research. We’re enlisting the helpof students, who are part of a unique research-writing program called StudentsPromoting Awareness of Research Knowledge (SPARK). SPARK started at theUniversity of Guelph 15 years ago, to give students an opportunity to learn howto write research news stories. Five years ago NSERC became involved and hashelped launched SPARK-supported programs at more than 20 research-intensive educational institutions across Canada. All stories in Advance are written by students.

Through their stories, you’ll see how AFMNet is built on leverage and syn-ergy, with the ultimate goal of ensuring Canada's pre-eminent role in foods andagricultural materials research. We’re establishing a system of researchers thatwill help generate the knowledge and technology needed to develop commercially viable, socially acceptable value-added products and processes thatbenefit all Canadians, and that can be sold around the world – a crucial endeavour for an exporting nation like ours.

We hope Advance enhances your understanding of this vital part of Canada’s agri-food and life sciences economy. I welcome your comments.

Dr. Rickey YadaScientific Director

Transformingresearch intovalue forCanadians

Dr. Rickey Yada

3AFMNet – ADVANCE / 2004

C O N T E N T S

Foods and Health

The better Band-Aid solution 8

A natural process for a natural product 9

Giving cellular foods more nutritional muscle 10

Are you really what you eat? 11

Cultivating new weapons in the battle

against resistant bacteria 12

A gel to make you well 14

Gutting fat buildup 15

Materials

You’ve seen these films before 16

A sticky situation 18

Pulp affliction 19

Lettuce and sunflowers: new sources of rubber? 20

Safe passage for bacteria 21

Fresher food, molecule by molecule 22

Consumer and Ethical Issues

Certified chow 24

Forbidden fruit, meat and veggies 25

Getting from concept to consumer 26

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Cover photo by Danny Abriel

The economy of the 21st century is becoming increasingly bio-based.Collaboration among diverse research disciplines is leading to an emergence ofvalue-added products derived from the agricultural and natural resource sectors.And innovative research is leading to breakthroughs in the development anddelivery of bioproducts, biopharma, biofuels and biomaterials. As we move further into the future, we will see continued convergence of science.

The Advanced Foods and Materials Network (AFMNet) is an excellent wayto maximize the benefits of convergence. Linking scientists and their respectiveareas of expertise on key projects will enhance research excellence across Canada.This is the premise of the Networks of Centres of Excellence program. AFMNetbrings focus to distinctly Canadian strengths — agriculture, food and naturalresources. This network is about ideas and bringing our leading scientists together to ensure Canada’s prosperity in a knowledge-based global economy.

Foods and materials share the same building blocks, and this network isfinding ways to work with them together. Because the structure of a materialdetermines its function, AFMNet researchers are trying to understand the structure-function of foods and materials — that is, the architecture of thesematerials, through their function.

As chair of the board of AFMNet, I am excited about the projects and knowledge that I see developing.

Dr. Murray McLaughlinChair


Dr. Murray McLaughlin

AFMNet– theNetworkof the 21stCentury

The Advanced Foods and Materials

Network is committed to improving the

lives of Canadians through innovative foods

and materials research.

Scientific Director

Rickey Yada

Associate Scientific Director

Allan Paulson

Network Manager

Larry Milligan

Financial Manager

Andrew Pulcins

IT Manager

Yaseen Shaik

Administrative Officer

Laurel Marshall

Communications Officer

Kate Roberts

Address correspondence to:

Laurel Marshall, Administrative Officer

150 Research Lane, Suite 215

Guelph, Ontario, Canada N1G 4T2

Phone: 519-822-6253

Fax: 519-824-8453

E-mail: [email protected]

Visit the AFMNet website:

www.afmnet.ca

Co-ordinating a 28-page magazine has kept Advance project co-ordinator Kate Roberts on her toes. But the second-year Universityof Guelph marketing student still finds time for her studies and for her favourite pastime, sports. Kate enjoys playing basketball, volleyball,soccer and squash, and hopes to head abroad after graduation to pursue graduate studies in business and marketing.

When he’s not busy writing news stories, fourth-year biochemistrystudent Rob Fieldhouse spends his time conducting research in theUniversity of Guelph’s science complex. His most recent work involveslearning about bacterial toxin structure and function. In this issue, Robreports on AFMNet work on novel hydrogels (see page 14).

Second-year drama student Alicia Roberts is at home on the stage and inthe newsroom. As a theatre enthusiast and a SPARK writer at theUniversity of Guelph, Alicia is exposed to diverse research activity acrosscampus. She writes about research ranging from the health benefits of soy to cellular nutrition (see page 10). After university,she plans to teach high school and participate in live theatre.

Heather Scott, a fifth-year mathematics major at the University ofGuelph, grew up on Manitoulin Island in northern Ontario before thedays of satellite and cable television. That meant she relied on thelocal paper, the Manitoulin Expositor, for the latest news, and shebecame an avid news consumer. Check out her story on how to control biofilms in pulp and paper mills on page 19.


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Improving the health and lives

of Canadians through foods and materials research

Dr. Rickey Yada, Scientific Director 150 Research Lane, Suite 215Guelph, Ontario, Canada N1G [email protected]

AFMNet is proud to be in partnership with these forward-thinking companiesand organizations:


3M Canada Company

Agriculture and Agri-Food Canada

Alberta Bioplastics Network

Amirix

Atlantic Canada Computing Consortium (AC3) (Memorial)

Avignon Diet and Nutrition Centre

Bowater Canadian Forest Products Inc.

Brenda Elliott, Guelph

Canadian Agri-Food Research Council

Canadian Bacterial Diseases Network

Canadian Food Inspection Agency

Canadian Genetic Diseases Network

Canadian Grain Commission,Grain Research Laboratory

Canadian Grain Commission, Oilseeds and Pulses

Canadian Institute of Fisheries Technology (Dalhousie)

Canadian Institute of Food Science and Technology

Canadian Institutes of Health Research,Institute of Aboriginal Peoples’ Health

Canadian International Grains Institute

Canadian Language and Literacy Research Network

Canadian Light Source Inc. (Saskatchewan)

Canadian Network of Toxicology Centres

Canadian Technology Network

Canadian Water Network

Casco Inc.

CellFor Inc.

Centre de recherche en sciences et ingénierie des macromolécules (Laval)

Center for Biofilm Engineering (Montana State University, U.S.A.)

Centre for Food and Soft Materials Science (Guelph)

City of Guelph

Dairy Farmers of Ontario

Dalhousie University

Degussa BioActives

Dietitians of Canada

Environment Canada, National Water Research Institute

Food Policy Institute/Rutgers University (U.S.A.)

Foragen Technologies Management Inc.

Forbes Medi-Tech Inc.

Guelph Regional Scanning Transmission Electron Microscopy Facility (Guelph)

Health Canada Food Directorate

Health Canada Natural Health Products Directorate

Health Law Institute (Alberta)

Heart and Stroke Foundation of Canada

IBM Canada Ltd.

Inimex Pharmaceuticals Incorporated

Institute for Research in Materials (Dalhousie)

KPMG Inc. and SISKINDS The Law Firm

Lakehead University

Let’s Talk Science

Loblaws

Manitoba Agriculture and Food

Materials and Manufacturing Ontario

Max Planck Institute of Colloids and Interfaces (Germany)

McCain Foods Limited

McGill University

McMaster University

Memorial University

MITACS Inc. (NCE in Mathematics of Information Technology and Complex Systems)

National Research Council, Plant Biotech Institute

National Research Council Canada,Neutron Program for Materials Research

Natunola Health

Nestlé, U.S.A. Quality Assurance Laboratory

Nestlé Product Technology Centre, Kemptthal

Nexia Biotechnologies

NIZO Food Research

Ocean Nutrition Canada

One Person Health Inc.

Ontario Pork

Oregon Health and Science University (U.S.A.)

Parrheim Foods

Petroleum Research Atlantic Canada

Processed Apples Institute (U.S.A.)

Protein Engineering Network of Centres of Excellence (PENCE)

Protein Fractionations Inc.

Rimon Therapeutics Ltd.

Ryerson University

Satake Centre for Grain Process Engineering (University of Manchester, U.K.)

Sciona

SHARCNET

SPARK (University of Guelph)

St. Francis Xavier University

Sun Microsystems

SynGene Biotek Inc.

Taiyo Kagaku Co., Ltd.

Technische Universität München (Germany)

TNO Nutrition and Food Research

Tokyo University (Japan)

Unilever R&D Vlaardingen,The Netherlands

University College Cork (Ireland)

University Health Network

University of Alberta

University of British Columbia

University of Guelph

University of New Brunswick

University of Ottawa

University of Victoria

University of Waterloo

U.S. Department of Agriculture

Warnex

T h i s p u b l i c a t i o n i s s p o n s o r e d b y

The betterBand-Aidsolution

Scientists worktowards artificialskin patch toheal wounds by Kate Roberts

The phrase “Band-Aid solution” is tak-ing on a whole new meaning — a positiveone — as AFMNet researchers work towardscreating wound dressings that release therapeutic compounds into skin woundsright when they’re needed.

Their goal is to create a dressing thatcontains a thick water-based jelly called ahydrogel. In turn, this hydrogel is modifiedto hold therapeutic agents — in this case,growth factors, naturally occurring com-pounds essential for healing. From a band-age-like adhesive strip, these therapeuticagents are released directly to the wound topromote healing and reduce infection.

“The healing of skin wounds such asthose from major surgery or burns is a complex process involving many biochemicalagents,” says research leader Prof. WankeiWan of the University of Western Ontario’sDepartment of Chemical and BiochemicalEngineering. “Deficiencies in these therapeutic agents result in a slower healingprocess. In the extreme, the wound maynever heal.”

Wan says this problem is especiallyprevalent among elderly people, diabeticsand immunocompromised patients.

He notes that there is currently noeffective treatment for chronic wounds. Thestandard wound repair process of cleansing,drying and bandaging is archaic and inefficient. It makes a scab, which forceshealing to take place under the skin. Thatproduces an unpleasant scar and slows downthe healing process.

Instead, says Wan, wounds need moisture and therapeutic compounds builtinto the dressing, so the wound can heal inan environment much like that inside thebody. He’s focusing on the delivery ofgrowth factors to the wound site.

Wan and his research group have seen arecent breakthrough. They designed ahydrogel material that can controllablyrelease growth factor-like molecules and anantimicrobial agent (important in controllinginfection in the wound site) at differentrates, mimicking the body’s natural healingprocess and delivering the growth factorswhen they’re needed.

Wan says his research won’t be completeuntil he can accommodate all the growthfactors important in wound healing in thedressing material. Each of these growth factors will be released at rates to coincidewith the needs of each healing stage. In themeantime, he’s working with an industrialpartner, Axcelon Biopolymer Corporation ofLondon, Ont., to continue the developmentand commercialization of the wound dressing.

“Wound dressing is a global concept,”he says. “If we can influence factors that helppromote chronic wound healing, we cansave health-care systems a lot of money andlet patients live a much more comfortableand normal life.”

In addition to Wan, the multidisciplinaryresearch team includes University of WesternOntario physics professor Jeff Hutter andmicrobiology professor Bosco Chan, who isalso a research scientist at the RobartsResearch Institute.


In some cases, wound dressings may actually slow the healing process. Prof.Wankei Wan is creating an alternative that is moist andreleases therapeutic compounds.

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Extraction for cancer-fighting lycopene holdspromise for othernutraceuticals, too by Kate Roberts

With the growing interest in functional foods designed toreduce cancer risks, drugstores can hardly keep enough of thepopular antioxidant lycopene on the shelf. But currentlycopene extracts are simply dried tomato skins, low in purity.That’s led University of Alberta food science professor FeralTemelli and University of Guelph physics research associateBruno Tomberli to try using a form of carbon dioxide toimprove lycopene extraction processes.

“This solvent has a high probability of extracting greateramounts of lycopene,” says Tomberli. “And unlike other solvents used today, it won’t leave behind any unwanted potentially toxic residue.”

The carbon dioxide they’re using isthe same type humans exhale, exceptit’s warmer and under high pressure. Inthis state, carbon dioxide is called asupercritical fluid (SCF) because it’sbeen taken to a temperature and pressure above what’s called the criticalpoint, where there’s no longer a difference between a gas and a liquid.

For carbon dioxide, the criticalpoint is 31 C and 73 atmospheres (73times normal atmospheric pressure).Here, carbon dioxide behaves more likea liquid and can get into a tomato skinand dissolve the lycopene. As a gas, car-bon dioxide can penetrate the skin of atomato, but it’s too light to grab on tothe lycopene and carry it away. As aSCF, it’s denser and has the ability tosuccessfully relocate the lycopene.

The proposed method of getting lycopene out of tomatoesis even simpler than conventional extraction techniques. Whenconditions are right — that is, anywhere above the criticalpoint — the lycopene gets taken up by the carbon dioxide.From there, the researchers reduce carbon dioxide’s pressure sothat it behaves like a gas again. It then loses the ability to holdon to the lycopene, which literally falls out in solid form. Thiscan then be collected and made into high-purity tablets.

The percentage of lycopene in the extract can be increasedby dehydrating the tomato skins prior to the procedure. Theresearchers are also looking at other solvents that increaselycopene’s ability to be taken up by SCF.

Although their current research is focused on lycopene,Tomberli says it won’t stop there. Increasingly, health-conscious consumers are demanding natural products and natural extraction techniques. Current conventional solvents,most of which are petroleum-based, can leave residues on theextracted products and can pose environmental problems suchas leaks and harmful emissions. Temelli says supercritical carbon dioxide could help replace the petroleum-based solvents being used in food processing today.

“Governments are placing strict regulations on howorganic solvents are used, and consumers are demanding ‘natural’products,” he says. “This project couldn’t be more timely.”

Tomberli, along with University of Guelph professorsSaul Goldman and Chris Gray, is focused on extraction theory and fundamentals. Temelli, working with University ofAlberta professors Selma Guigard and Suresh Narine and post-doctoral researcher Marleny Saldana, is primarilyinvolved in experimentation.


(L-R): Bruno Tomberli, Selma Guigard, Feral Temelli and MarlenySaldana are using new methods to extract lycopene from tomatoes.

A naturalprocess for anatural product

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Giving cellularfoods morenutritionalmuscleCellular researchhelps value-added productsmaintain qualityby Alicia Roberts

Adding value to basic commodities isthe goal of every primary-product economysuch as Canada’s. Adding value usuallymeans further processing and manufacturing,which creates jobs by turning the likes ofsoybeans into steering wheels or enhancingthe health of Canadians by enriching milkwith the essential fatty acid DHA. Butprocessors face many challenges in creatingthese value-added products. This is especiallytrue for foods that have an aerated cellularstructure, such as bread, extruded snackfoods, ready-to-eat cereals, cakes andmuffins. A failure of the so-called biogeniccellular solids (meaning they’re made frombiological materials) to stand up to the newprocessing demands can cause the productto degenerate, typically in appearance andtaste. If this happens, the product will alsofail on store shelves.

University of Manitoba researchersMartin Scanlon, Food Science, and JohnPage, Physics, want to give the cellular buildingblocks of these products more nutritionalmuscle. They’re studying the structure andfunction of what’s called cellularity — theorganization of food components into cellular structures. The approach they

envision is to add extra nutrients to productsusing processing strategies specificallydesigned to prevent impairment of the cellular structure by those nutrients, therebymaintaining the quality of the original product.

To study the structure and organizationof cells and cell walls in these products, Pageand Scanlon are using low-intensity ultrasound. This advanced materials charac-terization tool is helping them understandhow cellular structures can be created andcontrolled during the production of value-added food products.

Their current passion for complex foodsystems has brought them to a study offlaxseed in bread dough. Flaxseed has beenfound to significantly reduce the risk ofheart disease in humans. But when flaxseedis added to dough, the bread collapses during baking and the final product is hardand dry. The improved understanding of cellular structures that is emerging fromtheir research should enable problems suchas this to be resolved.

Scanlon and Page’s future research planscall for creating brand-new edible cell wallmaterials from nutritious molecules extractedfrom plants. To do this, they will use super-critical carbon dioxide (SCC), a fluid thatcan be used to permit self-assembly of nutrient molecules that constitute the cellwall material, while also forming the gasCO2 that creates the cellular structure fromthose cell wall materials.

In the second stage of the SCC research,Scanlon and Page will use the SCC to fabricate cellular structures that can holdadditional nutrients within the cells, therebyadding further nutritional value to theseinnovative consumer food products.

In addition to researchers at theUniversity of Manitoba and their international collaborators, other AFMNetresearchers involved in this project are Profs.Suresh Narine and Feral Temelli of theDepartment of Agriculture, Food andNutritional Sciences at the University ofAlberta and Prof. Ben Newling of theDepartment of Physics at the University ofNew Brunswick.


Researchers are trying to improve the cellular structure in flaxseed bread to prevent it from collapsing during baking.

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What’s in your DNA may soon determine what you put on your plate, asresearchers from the University of Torontoand the University of Guelph team up toinvestigate how diet interacts with thehuman genome to affect risk for variouschronic diseases.

Prof. Ahmed El-Sohemy of Toronto’sDepartment of Nutritional Sciences is developing an extensive database of diet,genotype and disease biomarkers — physicaltraits used to measure the effects of a disease — for humans.

“It’s no longer sufficient to only measure how much people eat of a certainfood,” says El-Sohemy, who holds a CanadaResearch Chair in Nutrigenomics, the studyof gene-diet interactions. “We want to relatediet to various health outcomes or risks ofdisease. And we also have to start factoringin how people metabolize these foods.”

He uses the example of dieting to explain the aims of this project.

“Some people who go on a low-fat dietwill see a decrease in their blood lipid levels.Others won’t see a change at all because of aspecific form of a gene they carry. A thirdgroup of people with yet a different genotype will actually see the contrary resultand their blood lipid levels go up. In thatway, a low-fat diet may actually cause somepeople harm.”

To test how food can affect individualswith different genes, the researchers willrecruit a large number of subjects, collectdietary information, look for disease biomarkers such as blood cholesterol (a biomarker of heart disease), and isolateDNA from blood samples. Blood also provides other strong predictors of some major chronic diseases, including cardiovascular disease, diabetes and osteo-porosis. To find these, El-Sohemy and histeam will look at blood parameters of somenutrients, including caffeine and vitamin E levels.

This research might be able to explainwhy scientific studies in different parts of theworld contradict each other. Because differentpeople living in differentplaces have varying genotypes,a genetic study performed inJapan, for example, couldyield far different resultsfrom those obtained inFinland, says El-Sohemy.That means this study couldhelp find the exact generesponsible for certain characteristics in differentpopulations. With Canadiansbeing such a geneticallydiverse population, thisresearch could be highly relevant to them, he says.

Another outcomemight be personalized diets,nutritional advice or medicine.If researchers identify a subpopulation that benefitsmost from a particulardietary component, it’s possible to develop func-tional foods targeted to thatpopulation. El-Sohemy sayssome services like this arealready being offered bycompanies on the Internet,but the science is still in itsinfancy. He believes it’ssomething Canadians willsee in the not-too-distantfuture.

Profs. Marica Bakovicof the University of Guelphand David Jenkins of theUniversity of Toronto areco-researchers on this initiative. Bakovic isfocusing on lipid metabolism; Jenkins, whoholds a Canada Research Chair inMetabolism and Nutrition, will study biomarkers of heart disease and diabetes,and will provide expertise in clinical nutrition and dietary assessment methods.

Prof. Ahmed El-Sohemy istesting how your genes influence the way your system breaks down food.

Researchers test how diet interacts with humangenes to affect disease riskby Kate Roberts

AFMNet – ADVANCE / 2004

Are you really what you eat?

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Antibiotic-resistant bacteria that ravagehuman health and spoil food may have mettheir match. A University of BritishColumbia researcher is using peptides —naturally occurring protein fragments withantimicrobial properties — to kill disease-causing bacteria as effectively as antibioticsdid in their heyday.

Peptides are present in the immune systems of all animal species, includinghumans. But they’re prohibitively expensiveto extract from animal sources. That’s ledProf. Robert Hancock of the Department ofMicrobiology and Immunology to considerplants as a cost-effective way to manufacturepeptides, for use in everything from pharmaceuticals to additives that inhibitfood spoilage.

“Peptides have tremendous potential asantimicrobials,” says Hancock. “If we canfind a way to lower production costs, we willhave a fresh new weapon in the war againstdisease.”

For the past 15 years, he has been studying the bacteria-fighting properties ofantimicrobial peptides. Together with Profs.John Vederas of the University of Albertaand Santosh Misra of the University ofVictoria, he has demonstrated that peptideskill antibiotic-resistant bacteria whileenhancing the body’s innate immunity andprotecting it during healing.

Unlike most conventional antibiotics,antimicrobial peptides can kill bacteria rapidly, within five minutes of application.That feat is usually observed only with disinfectants and could be exploited to create topical medicines for mouth, eye, earand skin infections, says Hancock.

Peptides could even be used as an aerosol spray forlung infections. But for these aspirations to be realized, scientists must find an inexpensive way to produce peptides, something Hancock and Misra are attempting byusing plants as peptide factories. By cloning antimicrobialpeptides into plants, their research teams have been able tocultivate large amounts of them in a relatively small area.The researchers say this process may one day make peptide-based pharmaceuticals affordable.

Preventing food spoilage is another possible application for these plant-produced peptides. Bacteriacause meat and dairy products to spoil rapidly. Peptidescould be used as a natural food preservative and as a way toprotect consumers from food-borne pathogens such as Salmonella and E. coli.

Plants themselves may benefit from this research. Morethan 25 per cent of the world’s crop production is lost tomicrobial diseases each year, and Hancock hopes his workwill also be used to produce peptides that help plants fightoff disease.

Although peptide overuse could lead to peptide-resistant bacteria in the same way that antibiotic overusehas caused antibiotic-resistant bacteria, the risk is extremelylow, he says. A traditional antibiotic may kill most bacteriabut not all, and the survivors go on to multiply, creatingnew bacteria populations that are resistant to that antibiotic. In contrast, laboratory trials have shown thatpeptides kill all bacteria in a sample, leaving no survivors toproliferate.

With fewer and fewer options to treat disease,Hancock believes peptides could represent a new class ofantimicrobial agents to help increase crop productivity, prolong food shelf life and maintain people’s health.

His work is funded by the Advanced Foods andMaterials Network, the Canadian Bacterial DiseasesNetwork, the Canadian Cystic Fibrosis Foundation, theCanadian Institutes of Health Research and GenomeCanada. Hancock also holds a Tier 1 Canada ResearchChair in Pathogenomics and Antimicrobials.


Foods and Health

Cultivating new weapons in thebattle against resistant bacteriaUsing plants as allies, researcherlooks towards a new class of antimicrobialsby Heather Scott

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Researchers are manufacturingpeptides in plants to kill disease-causing bacteria.

Taking stock of theworld’s crops

1. Agriculture under attack: Controlling plantdisease is a major issue for farmers worldwide.Crop losses caused by bacteria, viruses andfungi — and the pests that carry them — areestimated at upwards of 25 per cent world-wide, accounting for hundreds of billions ofdollars worth of damage every year.

Source: news release on APSnet website, con-tributed by G.A. Fermin-Muñoz, B. Meng (U ofG professor), K. Ko, S. Mazumdar-Leighton, A.Gubba and J. E. Carroll

ht tp : / /www.apsnet .org /on l ine / feature/BioTechnology/Top.html

2.The gang of four:Rice,maize,wheat and pota-toes account for 50 per cent of world foodconsumption. Epidemic diseases such as smut(maize), rust (wheat), scab (potato) and streakvirus (rice) can cause hunger and starvation indeveloping countries that depend on these staple crops.

Sources: Marcia P. McMullen and H. ArthurLamey, Extension Plant Pathologists, NorthDakota State University

http://www.ext.nodak.edu/extpubs/plantsci/pests/pp705w.htm

Karen Rane and Gail Ruhl, Department ofBotany and Plant Pathology, Purdue University

http:/ /www.btny.purdue .edu/Extension/Pathology/CropDiseases

3. An ounce of prevention: Methods of controlling plant disease include using non-contaminated seeds from certified seed growers, rotating crops, cleaning machinerybetween uses and spraying chemicals such asherbicides, fungicides and insecticides.

Source: Saskatchewan Centre for SoilsResearch at the College of Agriculture,University of Saskatchewan, Saskatoon

http://interactive.usask.ca/ski/index.html

http://interactive.usask.ca/ski/agriculture/crops/management/protection.html

4. Genes: the next wave? Researchers are usingselective breeding and techniques such as genetransfer to create plant varieties that are resistant to disease.These varieties help reducecrop losses.Antimicrobial peptides such as theones Hancock is developing may one day protect plants from bacterial disease andreduce dependence on pesticides.

Source: R.E.W. Hancock Laboratory,Department of Microbiology and Immunology,University of British Columbia,Vancouver, B.C.

http://www.cmdr.ubc.ca/bobh

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A gel to makeyou wellby Robert Fieldhouse

Some medicines are more effective ifthey’re ingested or absorbed gradually, butthat’s not always possible. Consider time-release oral capsules: they’re made withlayers of material that dissolve under different conditions, delivering active components to several points in the digestivesystem. But these capsules don’t always offerthe delicate timing and accurate dosages thatcould maximize a medicine’s effectiveness.

Enter the hydrogel. It’s a complex gelatin-like substance that could offer aneffective conduit for delivering desirablecomponents such as medicines or nutrientsto the body at the right time and in the right dose.

Prof. Allan Paulson of the Departmentof Food Science and Technology atDalhousie University and Prof. DérickRousseau of the School of Nutrition atRyerson University are leading a collaborativeproject to produce novel hydrogels that havewide-ranging health applications.

“Ideally, we want to develop hydrogelsas a platform with many potential uses,” saysRousseau. “With their potential to fine-tune

Hydrogels:here today, heretomorrowby Robert Fieldhouse

Although hydrogels may soundfar out and futuristic, they’vealready found numerous present-day applications, from medicineto waste treatment. Some everyday hydrogels include:

• wound dressings and artificial skin materials that maintain a moist environment, keeping tissue soft and speeding healing

• disposable diapers that absorb urine

• soft contact lenses

• tiny discs for sensors that detect glucose levels in diabetics

• crystals that release water and fertilizers in soil gradually and evenly

• beds for energy-efficient water recycling to keep pulp and paper effluent from overburdening waste-treatmentplants.

And that’s only the start.AFMNet researchers AllanPaulson and Dérick Rousseauplan to create microscopic capsules that contain a naturallyoccurring protein. Whenreleased, this protein attacks dis-ease-causing bacteria, killing themand lowering risks for disease.


the release of medicinal or other desirablecomponents, these new hydrogels couldimprove the well-being of Canadians.”

The hydrogels Paulson and Rousseauare developing can be designed to containsubstances such as antibiotics, proteins,nutraceuticals, anti-cancer agents or beneficial bacteria. The goal is for the hydrogels to release these substances at adesired rate when triggered by specific conditions such as changes in temperature,acidity, electricity or light. That way, thesecomponents can be released to patients in acontrolled manner.

Rousseau says it’s a more effective wayto get to the right part of the body at theright time, while preventing componentsfrom being released unintentionally wherethey aren’t needed or desired. He envisions ahigh concentration burst followed by a sustained release of lower concentrations, tomake medicines quick-acting and long-lasting.

Hydrogels have typically been uniformmixtures made by mixing certain powderswith water. Now, Paulson and Rousseau areusing a phenomenon called “phase separation” to make gels that control theindividual components’ release. Thisapproach is not unlike the principle thatkeeps oil and water apart in salad dressing.Prof. David Pink of the Department ofPhysics at St. Francis Xavier University ismodelling these hydrogels using computersimulations in an effort to predict whichhydrogels will most effectively deliverdesired components.

The researchers will soon select andincorporate the first desirable componentsand figure out how they interact.

“Hydrogels may provide a link withindustry and cutting-edge companies thatbenefits Canadian society and health,” saysRousseau.

He and Paulson are collaborating with Prof. Amyl Ghanem and post doctoralfellow Michael Nickerson of DalhousieUniversity, and graduate students RizwanKahn, Shane Hodge and Simon Veith ofDalhousie and Ryerson universities.

This research is sponsored by theAdvanced Foods and Materials Network.

New applications for hydrogels are beingexplored by AFMNet scientists (L-R) AmylGhanem, Michael Nickerson and AllanPaulson of Dalhousie University.

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Abdominal girth in men, also known asmiddle-age paunch, is associated withincreased risk of heart disease, stroke, diabetes and even cancer. If some of the fattytissue in this area can be reduced, the risk forthese diseases decreases. Prof. Peter Jones ofMcGill University is studying whether apopular weight-reducing nutraceutical calledconjugated linoleic acid (CLA) can reallyspur on steady, healthy weight loss inhumans.

“CLA has shown very beneficial resultsin previous documented studies,” says Jones,“so we’re trying to take it a few steps further,particularly in the largest areas of fat mass inour bodies.”

The project uses magnetic resonanceimaging (MRI), a technology that can iden-tify minuscule changes in body mass. Jonesand his research group will use this technique to see whether CLA — a fattyacid found in beef and dairy fats — canaffect body weight, overall body fat andregional adiposity (having fat in specificplaces and not others) when administered incontrolled diets.

The testing procedure involves humanvolunteers who are being fed a specific diettailored to their own estimated energy needs,with or without CLA, in randomized trials.Regimens will include an eight-week dietthat includes 3.5 grams of CLA per day, thena washout period in which the volunteerscan eat whatever they wish, followed byanother eight-week period without any CLAadded to their diets. Body composition willbe measured using MRI at the beginningand end of each eight-week period.

Jones predicts the CLA will increase the“rate of burn” ratio of body fat to body energy by about 100 calories per day. Thatwould add up to some 3,000 calories permonth or one pound of fat lost after 30 days.

If he and his team can discover wherethe fat loss is taking place in the body, thisresearch has the potential to control diabetes, stroke, cardiovascular disease andcancer by limiting where fat is stored.

Prof. Hélène Jacques of Université Lavalis working on diet formulation and fattyacid analysis. Dalhousie University professorRoger McLeod is performing cholesterolanalysis and measuring the fatty acid composition of the blood to determine theimpact CLA has on fat profiles.

Jones says if CLA shows promise, thecommercial potential for CLA-enrichedfoods is huge. A possible product in thefuture, for example, is CLA-enriched milk,which could expand on the success of thenew DHA-enriched milk that recently hitgrocery stores. DHA, an omega-3 fatty acidtransferred into cow’s milk from a specialfeed, supports development of the brain,eyes and nerves.


Fatty acid couldhelp humanscut fat

Conjugated linoleic acid(CLA), a fatty acid found insome meat and dairy fats, isbelieved to have human healthbenefits associated with weightloss and cancer prevention. Itisn’t produced by the humanbody, but it can be obtainedthrough foods such as wholemilk, butter, cheese, beef andlamb.

CLA was discovered in 1987when researchers observed thata beef extract appeared to be ananti-carcinogen. They later identified it as CLA.

Potential human health benefits associated with CLAinclude:

• increased metabolic rate

• decreased abdominal fat

• enhanced muscle growth

• lower cholesterol and triglycerides

• lower insulin resistance

• reduced food-inducedallergic reactions

• enhanced immune system.

The bulk of CLA research todate has been based on animalmodels and provides the foundation for current studieson CLA’s potential impact onhuman health.

~KR

With the increasing use of CLA supplements to promote weight loss, AFMNetresearchers are investigating how effective the nutraceutical really is.

Gutting fat buildup

Weight-reducing nutraceutical gets a chance to show its stuff by Kate Roberts

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By themselves, bacteria are vulnerable todrugs and other threats. They’re much saferwhen they get together, settle down on surfacesand form communities known as biofilms.These biofilms, which are layers of bacterialcells that coat moist surfaces, can endangerhuman health, disrupt industrial processes anddrain billions from the economy each year.

Biofilms can be as thin as a single cell (one thousandth of a millimetre) or thickerthan a human finger. They’re so adapted thatthey initially often go unnoticed, coating andsometimes degrading teeth, human lungs,computer keyboards, pipelines, water conduitsand rocks deep beneath the Earth’s surface.

Now, AFMNet researchers are creatingmathematical models and using them in computer simulations to understand how thesebacterial communities work. They hope todevelop better strategies to stop the bacteriafrom causing problems or to harness theiractivity for beneficial uses.

Prof. David Pink of the Department ofPhysics at St. Francis Xavier University likensthem to urban communities.

“Bacteria are organized in biofilms theway humans are organized in cities,” he says.“They might well represent the largest biomasson the planet. We can’t afford to ignore theireffects, good or bad.”

Whether harmful or beneficial, biofilmsplay a big role in society. Some cause pipelinecorrosion; others can actually clean up oil spillsbecause they degrade oil. Still, their harmfuleffects currently outweigh their benefits, andthey cost society tens of billions of dollarsannually, says Pink. Biofilms can reduce fluid

flow in pulp and paper production, producetoxic products in water and play a role inhuman diseases such as cystic fibrosis (biofilmsline the lungs and cause mucous to overproduce, creating respiratory difficultiesthat can result in death). Controlling andmanipulating biofilms could contributeimmensely to human society, from both healthand economic perspectives.

So Pink is leading a collaborative projectto create mathematical models of biofilms.They’re complex, so his group analyzes themusing computer simulations. Simulatingbiofilms can help researchers understand themand ultimately solve problems they create — or take advantage of good things they do.

Constructing models involves setting upmathematical equations that accurately represent bacteria’s behaviour as they settle onto a surface and create a biofilm. Eventually,the models will allow Pink and his colleaguesto predict experimental outcomes and point tostrategies to control and manipulate biofilmsso they can benefit society.

The researchers hope to further the understanding of biofilms’ initial attachmentprocess and structural changes that take placeas they grow through time. It’s known thatafter bacteria stick to a surface, they produce asticky “extracellular polymeric substance”(EPS), which is made up of proteins, sugarsand protein-sugar complexes. The EPS playsmany potential roles in the biofilm, providingstructural support and strategic defence, trapping food and creating natural channels fornutrient and waste transport.

A second goal is to find out more aboutEPS structure and dynamics, particularly howit changes through time in flowing and stagnant water. Pink hopes to have a workingbiofilm model that can accurately simulatenumerous biofilm types and conditions byyear’s end.

“This model will be generic, so it can beeasily adapted to different conditions, different


Materials | Biofilms

You’ve seen these films beforeBiofilms are costly, persistent ... and everywhereby Robert Fieldhouse

Biofilms can reduce fluid flow in

pulp and paper production,

produce toxic products in water

and play a role in human

diseases such as cystic fibrosis.


bacteria, different surfaces and variations in theEPS,” he says.

He predicts that one or two major applications such as food materials or wounddressings will be conceived, with perhaps adozen in total before the project wraps up.

Pink’s collaborators include Profs. TerryBeveridge, John Dutcher and Hermann Eberl,University of Guelph; Lisbeth TruelstrupHansen and Allan Paulson, DalhousieUniversity; Heidi Schraft, Lakehead University;Gary Slater, University of Ottawa; AlexeiBoulbitch, Motomu Tanaka and AndreasBausch, Technical University of Munich; PeterPoole, Laurence Yang and Carl Adams, St. Francis Xavier; and Adam MacDonald,University of New Brunswick. Also participatingare senior research associate Bonnie Quinn andstudents Michel Gallant, Melodie Need, LouiseBrennan and Dave Mackenzie of St. FrancisXavier.

This research is sponsored by the AdvancedFoods and Materials Network, the AtlanticInnovation Fund (Atlantic CanadaOpportunities Agency) and the NaturalSciences and Engineering Research Council.

How biofilms form

1. Seeding. Individual bacteriaadhere to submerged surfaces wherenutrient deposits exist and formcolonies.

2. Growth. As bacteria colonies growand divide, they’re held together byEPS, helping maintain the biofilmstructure.

3. Maturation.Towering columns formthat allow fluid to flow through thebiofilm, carrying nutrients to bacteriadeep inside the film.

4. Dispersion. Parts of the biofilmbreak off and leave the colony, dis-persing bacteria to other areas of thesystem, where they seed.B

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A sticky situationFrom industrialtubing to teeth,bacteria cling toeverything andcan harm humanhealthby Kate Roberts

Like any good family, bacteria can hangon and stick together through almost anything — and that’s a real problem forhuman health and industry, says Universityof Guelph physics professor John Dutcher.Once bacteria get together near any surface,be it food-processing equipment or teeth,they can form a stubborn thin layer called abiofilm. Biofilms can clog industrial pipes,contaminate food and even cling to medicalimplants such as catheters, making them ahazard to human health.

Working closely with other AFMNetresearchers, Dutcher and his team are striving to understand how bacteria do this — and to develop new strategies to stop them.

“It’s important to discourage the attachment of bacterial cells on surfaces, orbacterial colonies could become extremelyhard to fight,” he says.

This project has multiple steps. First,Dutcher and his research group will look athow bacteria adhere to artificial and naturalsurfaces. Once they understand this processmore clearly, they will evaluate the effectiveness of antimicrobial peptide molecules (amino acid compounds thatdestroy potential disease-carrying micro-organisms) in removing bacteria.From there, they will develop strategies toprevent biofilms from forming, such as

modifying surfaces so they discourage the attachment ofbacterial cells or altering the bacterial cell itself so it doesn’tstick to surfaces.

One method Dutcher and his team are using to learnmore about biofilms is called atomic force microscopy, inwhich a tip at the end of a tiny rod — so small it can detectatoms — can be placed carefully on to bacterial cells. Bypressing the tip into the cell and measuring its deflection,the researchers can determine the pressure in the cell. Theadhesion between the rod and the cell can then be measured by retracting the rod from the cell. These measurements will give Dutcher more information abouthow bacteria in biofilms stick to surfaces.

Because this project involves aspects of microbiology,physics and chemistry, multiple techniques will be used tolearn as much about biofilms as possible, he says. Onemajor component of AFMNet bacterial biofilm researchinvolves computer simulations of biofilm growth and theinteraction of antimicrobial molecules with bacterial cellwalls. The experimental and simulation results can be combined to obtain a detailed understanding of bacterial biofilms.

For Dutcher, the potential outcomes of this project arehuge. For example, 40 per cent of all hospital-acquiredinfections are related to bacterial biofilm growth. The medical industry could use anti-biofilm technology ininvasive medical equipment such as catheters and jointreplacements, he says.

Dutcher’s research team includes University of Guelphmicrobiology professors Terry Beveridge and ChrisWhitfield, who both hold Canada Research Chairs. OtherGuelph members are physics professor Chris Gray, chemistry professor Saul Goldman and mathematics professor Hermann Eberl. Profs. Gary Slater of theUniversity of Ottawa and David Pink of St. Francis XavierUniversity are contributing their computer modellingexpertise by creating biofilm growth simulation programs.

Prof. John Dutcheris leading a team ofAFMNet scientistsexamining howbiofilms stick to surfaces.

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Pulp afflictionResearchersaddress bacteriawoes for pulpand paper millsby Heather Scott

Biofilms — bacterial structures that form on surfaces in moist environments — have their advantages and disadvantages (see sidebar).But the pulp and paper industry isn’t ambivalent about them: biofilms inpulp mills can clog effluent pipes, corrode machinery and interrupt production. Now, AFMNet researchers are trying to turn this costlyproblem into a new opportunity.

Prof. Heidi Schraft of the Department of Biology at LakeheadUniversity is leading a research team to characterize a material called theextracellular polymeric substance (EPS), the sticky mixture of proteinsand sugars that holds bacterial biofilms together. (For another story onbiofilms and EPS, see page 16.) The EPS protects biofilm bacteria fromdetergents, disinfectants, antibiotics and even heat. By learning moreabout how the EPS works, Schraft hopes to help rid pulp and paper millsof troublesome biofilms.

“Our goal is to discover what factors help biofilms form on surfaces,” she says. “Once we know this, we can find ways to limitunwanted biofilms in industry.”

The first step in herstudy is to observe thedifferent types ofbiofilms that form inpulp and paper mills. Allbacteria have specificenvironments they thrivein and specific nutrientsthey can use. Because different types of paperrequire different sets of

additives such as clays and starches, the biofilms thatform in different parts of a mill depend on which additives are used. And they change all the time, as conditions vary.

“We have taken four monthly tests so far,” saysSchraft, “and we have found a different kind of biofilm each time.”

Her research group is taking the biofilms from themill to the lab. They hope that understanding whatmakes biofilms stick, and the EPS’s role in helping them survive and flourish, will make it possible to control them.

Schraft’s research may also help protect water resources and lowercontamination risks. Because biofilms are resistant to disinfectants andbiocides, mills must use harsh chemicals to control their growth. Thesechemicals, which are toxic in large quantities, end up in the mill’s waste-treatment pond, where they interfere with the treatment process.If they make their way into rivers and lakes, they could pose a hazard tohuman, animal and environmental health.

Schraft is working with Lakehead professors Kam Tin Leung,Department of Biology, and Aicheng Chen, Department of Chemistry;Profs. Lisbeth Truelstrup Hansen and Allan Paulson of the Departmentof Food Science and Technology at Dalhousie University; Prof. NicholasLow of the Department of Applied Microbiology and Food Science atthe University of Saskatchewan; and Prof. David Pink of the Departmentof Physics at St. Francis Xavier University.

This research is sponsored by AFMNet.

The bacteria found in pulp andpaper mills clog pipes and damage machinery. By findingout what makes them sticktogether, AFMNet researchershope to control their growth.

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Lettuce andsunflowers:new sourcesof rubber?by Kate Roberts

You can’t get blood from a stone, butyou may be able to get rubber from sunflowers or even lettuce.

University of Alberta chemistry professorJohn Vederas has been working extensivelywith American collaborators to developindustrial-quality rubber from Canadian-grown crops such as sunflowers and lettuce.

“This technology could utilize Canada’svast agricultural industry in a whole newway by doubling the role of native plants,”he says.

Sunflowers were the springboard to thisproject. They’re among the 2,500 plantsworldwide that are known to naturally produce small quantities of rubber, but can’tgenerate sufficiently high-quality rubber tosatisfy the annual $28-billion US demandfor rubber-derived finished goods. SoVederas plans to identify the genes responsiblefor making rubber in the Canadian sunflower and replace them with rubber-producing genes from the rubber tree. Hehopes the rubber produced in the sunflower,unlike that from the rubber tree, will notinflame latex allergies.

He has also identified a brand ofCanadian lettuce that naturally producesrubber. In fact, its rubber is of such highquality that it competes well against the

rubber tree, so its geneswon’t need to bereplaced. Normally, thelettuce on grocery storeshelves has been selectively bred toreduce rubber quantities

because latex is unpalatable. But Vederashopes plant breeding and molecular biologytechniques can make this all-Canadian lettuce a viable rubber-producing crop at theindustrial scale.

Researchers are conducting tests toensure that the quality of rubber in the lettuce is as good as Vederas believes and tomake sure it’s possible to produce enough ofit. The researchers must identify all thenumerous proteins involved in producingrubber in the rubber tree, the sunflower andlettuce, and test allergenicity and sensitivityto the latex rubber from all three plants.

Rubber prices are currently controlledby cartels, and the rubber tree, which produces 2,000 to 4,000 pounds of rubberper acre, grows only in tropical climates.Both sunflowers and lettuce would makeexcellent substitutes for rubber because theygrow naturally in Canada, which means theycan withstand colder climates and can becultivated on a mass scale. The potentialimpact this could have on the Canadianagricultural industry is huge, Vederas says.

He has been collaborating withresearchers at Colorado State University,Oregon State University, the U.S.Department of Agriculture, the Universityof Arizona and the University of California,Berkeley. Vederas is also a Canada ResearchChair in Bio-organic and MedicinalChemistry.


Canadian lettuce and sunflowers naturally produce small quantities of rubber that could ultimately lessen the demand for conventional rubber.

Materials

Double identities

Sunflowers and lettuce areproving to be more than justpleasing to the eye and thepalate. They’re both being citedas promising — if unusual —alternative sources of rubber.

About 45 per cent of theworld’s rubber is obtained fromthe Hevea brasiliensis plant, atropical rubber tree native toSouth America. It’s grown mostabundantly in Thailand, Malaysiaand Indonesia, as well as in thewetter parts of Africa and thehumid tropics.

More than 40,000 industrialproducts and 400 medicaldevices are currently made fromrubber.But production problemsassociated with H. brasiliensis,such as lack of genetic diversity,uncertainty of supply and latexallergies, have promptedresearchers to investigate newways to produce rubber.

The key is to produce analternative source with “long”rubber molecules. These pro-duce a higher-quality, strongerrubber because there is moreattraction — and thereforemore strength — betweenlonger rubber molecules thanbetween shorter ones.

Researchers at the Universityof Alberta are focusing on one ofthe 69 species of sunflowerscalled Helianthus annuus becauseit grows well in Canada, especiallyin Alberta. It contains short rubber molecules now, but byintroducing the long moleculesof the rubber tree into the sunflower, researchers hope toproduce a higher-quality rubber.

Another point of focus is lettuce,Latuca sativa. It producesextremely high-quality rubberbecause its rubber molecule islong and resembles that of therubber tree. But, further study isneeded to determine its qualityand protein makeup.

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Safe passage for bacteria

The goal:Todeliver good bacteria alive and intactby Kate Roberts

Not all bugs are bad. In fact, a class ofnatural “good” bacteria called bifidobacterialive right in our bodies, where they help withlactose digestion and prevent bacteria, yeastsand viruses from colonizing the gut. Poordiets, age, stress, diarrhea and antibiotic usecause lower bifidobacteria counts inhumans. Supplements help, but these bacteria aren’t easy to replace.

Enter Lisbeth Truelstrup Hansen, afood science professor at DalhousieUniversity. She’s leading an AFMNetresearch group to examine the effects of bifidobacteria and develop ways to improvetheir delivery to the gut.

“Research has shown that certain strainsof bifidobacteria are effective in helping people with poor health or nutritionalhabits,” says Truelstrup Hansen. “However,it has yet to be confirmed that when supplemented in the diet, the bacteria areviable and healthy when they get to the large intestine.”

That’s what Truelstrup Hansen is setting out to do. She and her research group want to improve the vitality and functionality of the bacteria by encapsulatingand then incorporating them into foodproducts such as cheese and yogurt.

To start, the research team must develop a way to encapsulate the bacteriainto protective beads made of hydrocolloids(substances that form a gel with water) suchas gelatin or carrageenan. Normally, gastricand bile juices present barriers that candestroy bifidobacteria before they reach thelarge intestine. That means a protective beadis needed to help them survive both in thefood products and along the journeythrough the digestive tract.

Another big problem in this process is that bifidobacteriaare anaerobes, meaning they dislike oxygen. So any processing to encapsulate the bacteria into the beads mustbe performed in the absence of oxygen. That’s important tokeep the bacteria healthy and must be considered whenintroducing them into food products as well.

Once they’ve successfully encapsulated the bacteria,the researchers must incorporate them into food productsso they’re undetectable to the mouth, avoiding an unwantedgrainy texture for consumers. Truelstrup Hansen also plansto consider how the bacteria will survive in food productsthrough processing and storage.

In addition, her research group will test the hardinessof these bacteria by analyzing their stress response. Fromthis, the researchers hope to learn which strains are moresuccessful at surviving during exposure to adverse environments. They hope these findings will result in moreeffective screening and selection of health-promoting bifidobacteria strains in the future.

Truelstrup Hansen plans to further her research bycollaborating with AFMNet nutritioniststo see whether bifidobacteria can actually deliver the health benefitsthey’re touted to promote.

Her research team consists ofAFMNet researchers with wide-ranging expertise from across the country. Food microbiologist HeidiSchraft of Lakehead University isstudying the composition of biofilmsproduced by micro-organisms in thepulp and paper industry to see if thebiofilm hydrocolloids can be used as acoating material for bifidobacteria.Dalhousie food scientist Allan Paulsonand Ryerson University nutrition professor Dérick Rousseau bring theirexpertise in hydrocolloids and physicalproperties of foods to this project. St.Francis Xavier University physics professor David Pink is concerned withhow oxygen and acids might move inand out of the beads.

Two researchers from Agricultureand Agri-Food Canada are also part ofthe research team. MicrobiologistMartin Kalmokoff will examine thegenetic basis of the bifidobacteria’sresponses to stress, and microscopistPaula Allan-Wojtas will assist in studying the microstructure of the protective beads and the bacteria held within them.


Prof. Lisbeth Truelstrup Hansen isinvestigating naturally good bacteriaand their delivery to the gut.

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Fresherfood,moleculeby molecule‘Smart’ materialsresearchers startsmall for betterfood packaging by Robert Fieldhouse

“Intelligent” product packaging thatcontrols its own passage of air and water isjust one example of new small-scale materials being developed by an AFMNetresearch group.

Prof. Robert Prud’homme, Departmentof Chemistry, Université de Montréal, isleading a collaborative project to producewhat are called “smart” materials. Theseinclude packaging that can keep food fresh,depending on the surrounding conditionssuch as temperature, humidity and light.

To create these materials, Prud’hommeand his colleagues have to start small — atthe microscopic scale. They’ll consider themolecular properties of “nanostructures”(tiny structures on the surfaces of molecularchains called polymers), which are impossible to see and difficult to manipulate. But Prud’homme believes thesenanostructures can be chemically fine-tuned,so they can keep food fresh under differentconditions on the larger scale.

“We’re trying to control the small-scalenature of these surfaces precisely,” he says.“In principle, it’s possible to create materialsthat would react differently depending onthe environment.”

Here’s how these nanostructures work.

Researchers choose two different types ofpolymers, carbon-based molecular chainsmade up of many identical links carefullychosen for their chemical properties. Then,the individual polymers are stitched end onend to form new, longer chains that contain


Materials

both polymers in specific sequences. Thesenew chains, called “block copolymers,”assemble themselves under appropriate conditions to create a film or coating.

Prud’homme’s group can performchemical reactions to selectively modify

certain groups of polymers, fine-tuning thesurface’s interaction with molecules such asoxygen and water, so it’s dependent on external conditions. This principle allowssmart packaging to keep food dry in moistconditions, for example, or let water escapewhen it’s hot — simply by changing the surface of the material, without the packagingopening or closing. More intelligent packagingmaterials made from such processes may leadto fresher food down the line.

This project is in its infancy, butPrud’homme says biodegradable polymersmay eventually be used in this process, making packaging both intelligent and environmentally friendly. He also foreseesusing new materials to fine-tune interactionsbetween cells and polymers, which wouldopen the door to new nanostructure coatings that would allow better drug delivery. Such coatings would encapsulatedrugs, preventing blood proteins from binding to them and inactivating them,allowing the drugs to reach a target site andbe released at an appropriate rate.

“This project is just beginning,” says Prud’homme, “but if we succeed in controlling the surfaces, this work couldcontinue for many years to come, with manydifferent applications.”

Other researchers involved in this project include Geraldine Bazuin and AlexisLaforgue, Université de Montréal, and Prof.John Dutcher, University of Guelph. Thiswork is sponsored by AFMNet, the NaturalSciences and Engineering Research Counciland le Fonds québécois de la recherche sur lanature et les technologies.


Drug delivery is just one of the many applications in nanotechnology’s future,as illustrated here by this computer visualization of a block copolymer — twodifferent molecular chains joined together end to end — used to deliver adrug to the human body. Red represents hydrophilic (water-loving) regions,green represents the hydrophilic copolymer surfaces, blue represents waterand bright areas represent the drug.

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In particular, they’re comparing honeythat originates from two different plants:canola, which produces lower-quality honey,and borage, which yields high-quality honey (it’s derived from a plant that contains heart-healthy linoleic acid). Previously, it’sbeen shown that borage honey is often diluted with less expensive canola honey.

Low and Scaiano want to identifyunique patterns in the DNA (called“markers”) of both honeys, so theycan tell when honey is adulterated.

Their identification method isunlike any currently being used byother food detectives. Because they’restudying processed food products(where the amount of DNA is smalland hard to measure), they’ll use special fluorescent dyes that bind toDNA markers, illuminating them.For example, if the researchers aretesting borage honey and a canola

marker lights up, they’ll know the honey hasbeen adulterated.

Even though this project deals specifi-cally with honey, Low hopes the same tech-nique can be applied to other AFMNetresearch projects. Because many of theseprojects deal with the insertion of new ingredients, having 100-per-cent pure ingredients is vital, he says. This way,researchers obtain accurate results from thedesired ingredients, not adulterated ones.

Low’s research has been supported bythe National Food Processors Association(U.S.A.), the Processed Apples Institute, theU.S. National Honey Board, theInternational Maple Syrup Institute, MinuteMaid and Nestlé U.S.A. Mike McLaughlinof the U.S. Food and Drug Administrationcollaborated with Low on food authenticityissues. This project is funded by AFMNet.

When it comes to adulteratedfood,honey isn’t the only suspect.Other popular food productsoften investigated include:

Fruit juices — Less expensivejuices or carbohydrate syrupsare sometimes added to extendfruit juice.

Jams and preserves — Less fruit,or less expensive fruit, may beused. Some jams replace fruitcompletely with organic acids,sugar, colouring and minerals.

Fish — High-value species maybe substituted with common,less expensive species. Forexample, yellowfin, bluefin orskipjack tuna has been sold asalbacore.

Ground or instant coffee —Coffee plant husks, leaves orstems may be added to groundbeans. In some cases, adulterantssuch as chicory or dandelionroot, malt, cereals and starchhave been added to ground andinstant coffee.

Meat and meat products —Ground meats such as beef,pork, lamb and chicken may con-tain vegetable protein or proteinsources such as rabbit, horse,goat or mouse.

Wine — Wines of different variety, vintage or geographicalorigin may be substituted. Somewines may also be adulteratedwith sugar or different fruits.

Vegetable oils, especially virginolive oil — Less expensive oilssuch as canola or sunflower, oroil from olive pomace or olivefruit refining, may be substituted.

Vanilla extract — Vanilla’s activeingredient, vanillin, may be produced synthetically. Foodpackaging may also claim anuntruthful place of origin for thevanilla plant so the manufacturercan charge higher prices.

Herbs and spices — Groundspices may be substituted withnon-spice products of similartexture and colour. For example,paprika has been adulteratedwith toxic red lead.

Milk — Specialty milks such asewe, buffalo and goat milk maybe diluted with cow’s milk, orcow’s milk may be diluted withpowdered milk.

Eggs — Whole eggs may beimproperly graded or weighed.Egg-white powder may be diluted with less expensive protein sources.

Source: Prof. Nicholas Low,University of Saskatchewan

Certified chowLooking for truth behind Canadianfood productsby Kate Roberts

Consumer and Ethical Issues

Con artists, move over. Some legitimate-appearing food companies areplaying a shell game by providing false information about exactly what goes intotheir products. But AFMNet researchers areon the case. They’re developing new techniques to see whether food productsreally contain what their labels say they do.

From farm to grocery store shelf, foodcan get adulterated to pump up profits. Butthat hurts the food industry’s reputation,cheats consumers and constitutes a crime,punishable by fines or jail time. That’s whyProfs. Nicholas Low, Department of AppliedMicrobiology and Food Science at theUniversity of Saskatchewan, and TitoScaiano, Department of Chemistry at theUniversity of Ottawa, are developing methods that can positively identify originsof different food components.

Says Low: “When consumers purchasea food product, how do they know the product is really what it says it is?”

He and Scaiano hope to answer thatquestion by using a method that can detectsmall amounts of DNA, linking food ingredients back to their true origins. First,they’ll tackle the authenticity of honey, aproduct that comes in many different varieties, has varying quality and has beenknown to be adulterated to boost profits.

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Forbiddenfruit, meatand veggies

Internationalteam investigates cultural and religious viewsabout geneticallyengineered foodby Kate Roberts

Sweeter fruit, more tender meat, biggercrops: the promise of developing affordable,innovative foods with better nutrition andtaste offers many challenges for genetic engineers. And one hurdle few have considered, says University of Victoria philosophy professor Conrad Brunk, is theestablishment of good research-based guidelines for cultural and religious dietaryrestrictions.

That’s what Brunk and his AFMNetresearch group are aiming to do. They’refocusing on consumer acceptance of transgenes, the genes transferred from oneorganism into another using genetic engineering. Transgenes have opened up a cultural and religious can of worms for manypeople, he says, because some genes maycome from a food that their religion or culture forbids them to eat.

Brunk believes a better understandingof the issue is needed.

“Canada must clarify how cultural andreligious populations view the transfer ofgenetic material from ‘prohibited’ foodsources into otherwise acceptable foods,” hesays. “This has never been examined.”

He cites as an example Jewish kosherlaws and Muslim halal laws, which prohibit

eating non-ruminant mammals (such as pigs and horses), fish thatdon’t have scales (such as sharks) or any kind of shellfish. That meansmeat from a transgenic animal with a pig or shark gene could presenta problem for people committed to these dietary rules.

Many Buddhists and Hindus are vegetarians, so genetically modified vegetables containing transgenes from animal sources couldalso be a concern.

Researchers will hold focus groups with cultural scholars and religious followers, asking them about traditions, religious interpreta-tions and attitudes about issues such as biotechnology, patenting lifeforms, human stem cell use, and splicing and cloning human genesand tissues. Animal welfare researchers, vegetarians and religious leaders — representing Buddhism, Christianity, Judaism, Hinduism,Islam, Taoism and Canada’s aboriginal religions — will also be consulted about their views.

“This will make a good sample of the population because you cantalk with members of these groups as well as the leaders themselves,”says Brunk.

The eventual goal of this research is a multidisciplinary team-authored book summarizing the findings. The authors of the proposed book chapters will discuss how the views of focus groupmembers compare with common philosophies around the world.Although the planned book could help guide people’s diets and satisfygeneral interest, Brunk believes it will also be useful for food developers, regulatory bodies and industry. Regulators can use thebook as a guideline for what product information should be displayed, he says, and the food industry can gain a better understandingof what transgenes could make food products unacceptable to specific consumer groups.

Brunk is the AFMNet theme leader of Genetics, Ethics, Economics,Environment, Law and Society. His research team on this projectincludes investigators from five countries and nine universities, as wellas representatives of Health Canada, the B.C. Cancer Agency andPraxis Pacific.


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Canada’s multi-cultural population faces diverse dietary needs and restrictions.AFMNet researchers are working to establish research-based guidelines that accommodate these differences.

Researcher navigateswinding path towardcommercializationby Kate Roberts

A better mousetrap could be waiting behind any laboratorydoor, but that doesn’t mean the world will beat a path there.Many obstacles, including the intricacies of intellectual property rights and funding shortfalls for product development, lie in the path between concept and consumer.To ensure Canada maintains its place as a world leader in science, the path needs to be as straight as possible.

Enter McGill University law professor Richard Gold. Heand his colleagues are developing a framework to guideAFMNet researchers through the highly detailed commercialization process. They hope to help new discoveriesand technologies find their way more easily to an industrypartner or the public domain.

“Commercializing research is important because the goalof research is to benefit everyone — the public, the inventorand society,” says Gold. “And because this research is publiclyfunded, it should reach the public. It isn’t acceptable for a scientific discovery to sit on a shelf. We must be able to shareinformation, while providing the needed protection for innovation.”

Intellectual property rights encompass original productsor ideas with commercial value. This includes everything frombooks and designs to new products and industrial processes.The rights are in place to protect product and idea inventorsand developers.

But they can also act as barriers, blocking researchersworking on related projects from accessing relevant technology,and keeping beneficial innovations from getting to the publicquickly. Gold is working to ensure that technology is as widely available as possible and that sufficient funding is inplace to take ideas to market.

He notes, for example, that many researchers don’t have aclear idea about which technologies they’re allowed to usewhen conducting their own research. New materials andexperimental techniques may be subject to intellectual property rights or confidentiality agreements, and resolving


Getting fromconcept to consumer

these issues takes up valuable research time. Gold wants tochange that by researching and implementing improved policyto help researchers stay informed about what technology theycan access. Without appropriate intellectual property policies,new programs such as AFMNet may not be able to effectivelydevelop and commercialize their own technologies.

To identify the major commercialization and technology-transfer problems in Canada, Gold’s team has held one workshopand is planning to invite researchers, university administrators,industry representatives and government officials to discussissues at future workshops. Reports from these sessions will beposted on the AFMNet website (www.afmnet.ca) soon andsent to government officials so policy issues can be addresseddirectly by deci-sion-makers.

One emergingissue identified atthe first workshopis the funding gapbetween discoveryand commercial-ization. Right now, says Gold, universities generate ideas, andindustrial partners pick them up once they’re developed, butfinding funds for the crucial gap between idea and product isdifficult because the financial risks are often too high. Findingthe money to fill this void would help get more successfultechnologies to market, he says.

Gold is also addressing policy issues at the grantingagency level. Universities usually make decisions related tointellectual property rights, such as how ownership of an ideais shared. That’s fine for small-scale projects, but it’s morecomplicated for networks such as AFMNet that bring together researchers from different disciplines and institutions.In cases like these, granting agencies need to take a moreproactive role, he says.

“While our research results will not themselves have commercial potential, we hope they’ll assist researchers, industry and government at all levels in developing sound andsustainable intellectual property laws and narrowing researchfunding gaps.”

Gold is collaborating with McGill graduate student KarenDurell and Profs. Peter Phillips, Department of AgriculturalEconomics, University of Saskatchewan; Tim Caulfield,Health Law Institute, University of Alberta; and David Castle,Department of Philosophy, University of Guelph.

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Scientific directorRickey Yada isconcerned abouthow intellectualproperty rightswill be applied toAFMNet-fundedprojects.

Documents

Advance Magazine - Winter 2004/2005