Download Economic Significance of Microorganisms

Economic Significance of
Microorganisms
Microorganisms
• Microorganisms are small living things that can
only be seen under high power microscope.
• Microorganisms include:
–
–
–
–
–
Virus
Bacteria
Protozoa
Microscopic Fungi
Microscopic Algae
Use of Micro-organisms in environment
1. Fixation of atmospheric nitrogen
2. Decomposition of organic wastes and residues
3. Suppression of soil-borne pathogens
4. Recycling and increased availability of plant nutrients
5. Degradation of toxicants including pesticides
6. Production of antibiotics and other bioactive compounds
7. Production of simple organic molecules for plant uptake
8. Complexation of heavy metals to limit plant uptake
9. Solubilization of insoluble nutrient sources
10. Production of polysaccharides to improve soil
aggregation
Beneficial Microorganisms
• Antibiotics
• Food Production
• Soil Fertility and Bacteria and
Fungi
• Combating Pollution
Antibiotics
• Antibiotic is chemical substance produced
by microorganisms that can kill or inhibit
the growth of other microorganisms.
• Antibiotics kill or inhibit other organisms
by interfering the metabolic process in the
bacterium that is not found in the host.
Penicillin
conidia
conidiophores
phialides
Food Production
• Fermentation:
C2H12O6  2C2H5OH + 2CO2 + energy
• Dairy Products: cheese, yogurt and butter
• Wine and bread: yeast (Saccharomyces
cerevisaea)
Soil Fertility and Bacteria
and Fungi
• Formation of Humus:
– Organic compounds are decomposed by
saprophytic bacteria.
• Nitrogen Fixation
– Nitrogen  Ammonia
• Nitrifying bacteria
– NH4+, NH3 Nitrosomona NO2- nitrobacter NO3-
Combating Against Pollution
• Sewage Treatment.
• Oil spillage: Pseudomonas sp.can
digest the oil into harmless forms.
Sewage Treatment (1)
• Primary treatment
– In the sewage treatment plant the
solid organic matter is moved from
the sewage as sludge which may be
treated further to form fertilizer.
Sewage Treatment (2)
• Secondary treatment:
– The organic matter left in solution
and suspension are decomposed
rapidly by the added microorganisms (e.g. Bacillus,
Pseudomonas, Vorticella )
Sewage Treatment (3)
• Tertiary treatment:
– Finally all the micro-organisms are
killed by adding chlorine to the
effluent of the treated sewage which
can run into the rivers without
causing any pollution problems.
Water Treatment of HK
Microorganism in other
productions
vaccines
amino acid
Enzymes (invertase)
Vitamins (e.g. B2)
Harmful Organisms
• Causing Diseases.
• Food Spoilage.
This orange is covered by fungus.
A child infected by mumps.
Source from: Microbiology: Essentials and Application (2nd Ed.).
Source from : Microbiology: Essentials and Applications. (2nd Ed.)
Microorganisms and Diseases
• Pathogens are microorganisms that cause
disease in animals and crops.
• Any organisms that carry pathogen from
one living organism to another is called
vector.
Virus
• Virus cause diseases by disturbing the
homeostatic condition of the host cells.
Viral diseases
• Plant virus: Tobacco Mosaic Virus
• Human diseases caused by virus:
-Small pox
-Measles
-Influenza
-Hepatitis B
-AIDS
AIDS
• Acquire Immune Deficiency Symptom.
• It is caused by Human Immunodeficiency
Virus (HIV).
• Affects T-helper cells, making body defense
system unable to combat against disease.
• Mainly spread through sexual intercourse
and blood transfer.
HIV bud from the surface of
an infected Helper T cell
Hepatitis B
Pathogenic Bacteria
• Pathogenic bacteria caused diseases by:
– destroy the body tissues of the host directly
– excrete toxins
– release toxin from cell wall after death
• Diseases caused by bacteria:
–
–
–
–
Cholera, Typhoid fever
Pneumonia, Whooping cough, Tuberculosis
Gonorrhea, Syphilis
Food poisoning
The Structure of Bacteria
E.coli
Fungal Diseases
-Fungal diseases are called mycoses which
affect the skin, nails and hair follicles
Methods to control the
spread of diseases
1.


2.


Prevention
Personal and Public hygiene
Immunization
Treatment
Chemotherapy
Surgery
Food Preservation
• Spoilage of food is caused by saprophytic
bacteria.
• Basic principle of food preservation:
– Killing the microorganisms in food;
– Stopping or inhibiting their growth.
Pickling of Food.
Source from: Biology: A Modern approach. (2nd Ed.)
Food Preservation Techniques
Thermal Processing
Refrigeration
Drying
Food Additives
Canning
Smoking
Thermal Processing
Heating
Pasteurization
Refrigeration
Drying
Food Additive
Canning
Smoking