presence of microbes in air

1. AEROMICROBIOLOGY

3. 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.

5. It is the study of those invisible microorganisms (which are less 1mm in size & not visible through naked eyes) which are present in air.

6. 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.

7. 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.

8. Aerosols machine fans air conditioners vents Wind blown long suspension time Man's Actionsploughing digging excavation construction irrigation fertilizers The SOURCES of Microbes in Air Human/Animal breath cough sneeze talk laugh Water droplets fountains streams ponds rivers

11. sunlight

12. susceptibility Droplet Nuclei 1-4 µm dry solid of a droplet ability to travel distances

14. 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.

15. Indoor aeromicrobiology Aeromicrospora of pharmacy. Aeromicroflora of hospitals. Houses Aeromicroflora of storage materials.

16. 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.

17. Aeroallergens House dust allergens . Pollen grains. Cosmetics .

20. PHYLLOPLANE MICROFLORA (1) (5) Microorganism colonizes the leaves . Landing stage for the microbial propagules (2) Insects excreta on the leaf surface serve as food . Deposited by impaction, sedimentation under gravity and in rain and splash droplets (4) (3) Spores get nutrient diffused from leaf and pollen grains present on the surface

22. 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.

23. 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

24. Both higher and lower temperature causes damage to the microbes. High temperature causes deactivation of proteins and enzymes Lower temperature causes ice crystal formation.

25. MOISTURE STRESS High moisture causes death Low moisture causes damage to the lipid bilayer .

27. Double strand breaks

28. Alteration in structure of DNA And also effects Genome replication Transcription Translation

29. 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.