AEROMICROBIOLOGY

During 1930s the term aeromicrobiology was used to denote the air borne spores (e.g. fungi and other microorganisms )Further in 1951 ,the term was elaborated to include dispersion of insect population, fungal spores, bacteria and viruses.In 1964, the term included the research work of air borne materials of biological significance.

AEROMICROBIOLGY It is the study of those invisible

microorganisms (which are less 1mm in size & not visible through

naked eyes) which are present in air.

Study of aerosolization, aerial transmission and biological materials.It also includes the study of diseases transmitted through respiratory routes.The field of aeromicrobiology is important as it involves, Formation of aerosols .Their transmission and deposition in soil.

The important gases that effect the microorganisms are hydrogen sulphide, sulphur dioxide, carbon monoxide, chlorine, hydrogen fluoride, ozone , etc. The microbial forms are bacteria, fungi and actinomycetes , algae, spores of pteridophytes, pollen grains, micro insects and viruses.

The SOURCES of Microbes in Air

Wind blown long suspension time

Human/Animal

breath coughsneeze

talklaugh

Aerosolsmachine fans

air conditioners

ventsMan's Actions

ploughingdigging

excavationconstruction

irrigationfertilizers

Water droplets fountains

streams ponds rivers

3 Forms of Discharge

grouped via size and moisture content

Dropletsmucoussalivatalking

coughing sneezing

Infectious dust

dried secretionsculturing microbes

handkerchiefbed making

clothes sweeping

Droplet Nuclei1-4 µm dry solid of a dropletability to travel distances

survival limited by: humidity sunlight susceptibility

INDOOR AEROMICRBIOLOGY

It deals with microorganisms present in air in indoor environment.They are the microorganisms which are responsible biodeterioraton of storage materials, equipment , library materials and archives.

Indoor aeromicrobiology

Aeromicrospora of pharmacy.

Aeromicroflora of hospitals.

Houses

Aeromicroflora of storage

materials.

AEROALLERGENS AND AEROALLERGY

Allergy is caused by certain biological & abiological agents present in the atmosphere.

The allergy causing agents in the air are called aeroallergens.

The allergy caused by them is called aeroallergy.

Aeroallergens

House dust allergens . Pollen grains. Cosmetics .

PHYLLOPLANE

MICROFLORA

•Leaf surface habitat.

PHYLLOPLANE MICROFLORA Landing stage

for the microbial

propagules

Deposited by impaction,

sedimentation under gravity

and in rain and splash droplets Spores get

nutrient diffused from leaf and pollen grains

present on the surface

Insects excreta on the leaf surface serve as food .

Microorganism colonizes the

leaves .

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(2)

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Environmental parameters effecting microbes survival Microbes are continually in the state of

stress.Oxygen stress (OAF) and ionic stress. Temperature stress.Moisture stress.UV-radiation stress.

OXYGENIC AND IONIC STRESS

Higher level of oxygen and its reactive form causes inactivation of enzymes. Damage to DNA.Inactivation of nucleic acids.Naturally occurring ions causes ionic stress causes lightening, water shearing and ion displacement

TEMPERATURE STRESS

Both higher and lower temperature causes damage to the microbes.

High temperature causes deactivation

of proteins and enzymes Lower temperature causes ice crystal formation.

MOISTURE STRESS High moisture causes death Low moisture causes damage to the lipid

bilayer .

RADIATION STRESS

Shorter wavelength and X-ray causes damage to DNA by

Single strand breaks. Double strand breaks Alteration in structure of DNA And also effects Genome replication Transcription Translation

BIOAEROSOLS

Biological contaminants occurring as solid or liquid particles in air.

Size :0.1 -100µ

May be single or aggregate form

May be adhere to dust particles or surrounded by a film of organic or inorganic matter.

Pathogenic for plants, animal and human and also damage inanimate materials.