aeromicroby seminar 2007
DESCRIPTION
presence of microbes in airTRANSCRIPT
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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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.