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Crackingdownoncounterfeits:CreatingaDNAbarcodereferencelibraryofcommercialherbalproductstradedinSouthAfrica
Letlhogonolo Sello,RyanDRattray,MichellevanderBank
TheAfricanCentreforDNABarcdoing (ACDB),DepartmentofBotany&PlantBiotechnology,UniversityofJohannesburg,P.O.Box524AucklandPark,SouthAfrica- 2006
Background: Herbal products have been used for different purposes throughout human history, especially to treat numerous health ailments. Generally, it is believed that herbal products areaffordable and safer to use compared to modern medications. The increase in the demand for herbal products places suppliers under immense pressure to deliver. Subsequently, commercial herbalproducts are often subjected to contamination or substitution of the main plant ingredient listed on the product label. This can result in reduced therapeutic potential and poses a serious health riskfor consumers. Currently, there are no standard practices or systems available for the identification of species used in herbal products in South Africa, other than chemical analyses alone. As a result,the industry suffers from fraudulent and unethical practices. Results: A list consisting of 70 native plant species used in commercial herbal products traded in South Africa were compiled. All referencesamples and look-alike species (1 to 5 individuals per species) were sequenced using the core barcoding regions rbcLa and matK to compile the DNA database. The database was then used toauthenticate local products. Significance: This DNA barcode reference library, the first of its kind in South Africa, can provide pharmaceutical companies with a database against which they are able tocompare their sourced raw materials and verify their authenticity.
ABSTRACT
INTRODUCTION&AIM
The increase in the demand for commercial herbal products (CHP) placesuppliers under immense pressure to deliver and this results in increasedconcerns related to the safety and efficacy of the products (Ramanujam et al.,2017). Not being able to distinguish authentic products in their raw form orprocessed materials from their close relatives, inferior substitutes, adulterants,and counterfeits is a great challenge (Sun et al., 2016).
The absence of standard practices (other than phytochemical profiling) for theidentification and authentication of species used in South Africa, subjects theindustry to unethical and fraudulent practices (Vassou et al., 2016). Thesepractices may be prevented by enforcing a standard authentication system thatwill enable the marketing of authentic herbal products (Wallace et al., 2012).
Our aim was to create a DNA barcode reference library that can providepharmaceutical companies with a database against which to verify theauthenticity of their sourced raw materials.
MATERIAL&METHODS
REFRENCES&ACKNOWLEDGEMENTSNewmaster, S.G., Grguric, M., Shanmughanandhan,D., Ramalingam, S., and Ragupathy, S. 2013. DNA barcoding detects contamination and substitution in North
American herbal products. BMC Medicine, 11:222 http://www.biomedcentral.com/1741-7015/11/222Ramanujam, S., Kumar, J.U.S., Seethapathy, G.S., Newmaster, S.G., Ragupathy, S., Ganeshaiah, K.N., Shaanker, R.U., and Ravikanth, G. 2017. Species Adulteration
in the Herbal Trade: Causes, Consequences and Mitigation. Drug Safety. doi: 10.1007/s40264-017-0527-0Sun,W.,Li,J.J.,Xiong,C.,Zhao,B.,andChen,S.L.2016.ThePotentialPowerofBar-HRMTechnologyinHerbalMedicineIdentification.FrontiersinPlantScience,7
(367):1-10.Vassou,S.L.,Nithaniyal,S.,Raju,B.,andParani,M.2016.CreationofareferenceDNAbarcodelibraryandauthenticationofmedicinalrawdrugsusedin
Ayurvedicmedicine.BMCComplementaryandAlternativeMedicine,16,9-15.Wallace,L.J.,Boilard,S.M.A.L.,Eagle,S.H.C.,Spall,J.L.,Shokralla,S.,Hajibabaei,M.2012.DNAbarcodesforeverydaylife:RoutineauthenticationofNatural
HealthProducts.FoodResearchInternational, 49:446–452.
RESULTS
Figure 1: Schematic diagram showing the process of creating the DNA barcode library andauthenticating commercial herbal products sold on the South African market.
PHOTOCREDITS:Aloe:ByGilWalkerhttps://flic.kr/p/a8k6MdEmex:ByForestandKimStarrhttps://flic.kr/p/EcYzUXProsopis:ByDineshValkehttps://flic.kr/p/4onPEeLessertia:ByEricLuxhttps://flic.kr/p/6tbZuz
Based on the results obtained, 71% of the tested products were found to beauthentic and 29% of the products were determined to be substituted (Fig. 2A).High quality PCR products were obtained for rbcLa as compared to matK. Thiscoincides with the findings of Newmaster et al., 2013, who determined thatmatK is usually associated with poor PCR amplifications. Figure H & I show theplant species that were used as substitutes of some of the herbal productstested.
The significance of this study was to create a DNA barcode reference library, thefirst of its kind in South Africa, that can be used to authenticate CHPs. DNAbarcoding provides a quick, easy and accurate method of authentication.Though most of the products in this particular study were authentic, there maybe many subject to fraudulent activities. It is suggested that barcoding beincorporated as a quality control mechanism to thwart such practices andprotect the consumer market.
Figure 2: A. Pie chart showing the percentage of authentic and unauthentic South Africancommercial herbal products tested. Figure B. to G., shows several of the species listed on theproducts tested: B. Lessertia frutescens, C. Harpagophytum procumbens, D. Aloe ferox, E.Warbugia salutaris, F. Agathosma betulina & G. Prosopis juliflora. H. Camellia sinensis & I. Emexspinosa.
DISCUSSION&CONCLUSION
POSTERID:680
29%
71%
Authentic UnauthenticAuthenticVSUnauthenticCHPtestedinthisstudy
B
C
ED
F G
IH
A
B
G H I
D E F
CA