ECONOMIC IMPORTANCE OF BACTERIA,BENIFICIAL & HARMFUL USE OF BACTERIA, BACTERIA ARE USEFUL IN THE PRODUCTION OF ORGANIC ACIDS, DEAD & DECAYING,INCREASE SOIL FERTILITY,

1. BENEFICIAL& HARMFUL USEOF
BACTERIA
B.Sc.I Microbiology
Dr. Rachana Choudhary
Asstt. Prof. .SSMV ,Junwani Bhilai

2. WELCOME

3. SYNOPSIS
BENEFICIAL USE OF BACTERIA
• Primary decomposers
• Soil fertility
• Industrial importance
• In medicines
• Synthesis of Chemicals
• Insect Pest Control
• Bioremediation
• r- DNA Technology
• In food chain
HARMFUL USE OF
BACTERIA
• Reduction of soil fertility
• Food poisoning
• Human Disease caused by
Bacteria
• Plant Disease caused by
Bacteria

4. Bacteria - what comes to mind?
• Diseases
• Infections
• Epidemics
• Food Spoilage
• Only 1% of all known bacteria cause human diseases
• About 4% of all known bacteria cause plant diseases
• 95% of known bacteria are non-pathogens

5. Beneficial Use of Bacteria
1.Primary decomposers (Decay &
decomposition of Dead Organic matter)–
Several Saprophytic Bacteria are found in soil. They
bring about decomposition of organic matter and
change it into simpler and inorganic substances.

6. 2. Soil fertility
Bacteria play an important role in maintaining the soil
fertility
(i). By Nitrogen fixing bacteria
free living- Azotobacter & Clostridium
Symbiotic- Rhizobium
(ii). Nitrifying Bacteria- Nitrosomonas
(convert nitrogen to nitrite)
Nitrobacter (convert nitrite to nitrates)

7. 3.Industrial importance
(i). Acid production
Bacterium Mycoderma aceti converts solution into vinegar.
(ii)Fibre retting
Clostridium butyricum helps in separating the fibres in jute and sun
hemp.
(iii)Curing of tobacco and tea
Micrococcus candescence - peculiar flavour and taste of tea leaves this
process is called curing.Bacillus megaterium flavour and test to
tobacco leaves.
(iv) Dairy industry -Streptococcus lactis help in converting milk
into curd. Lactobacillus casei , Bacillus acidophilus & Lactobacillus
plantarum are also used in dairy industry.

8. 4.Importance of bacteria in medicines
(i)Antibiotics-
Streptomycin (Streptomyces griseus)
Neomycin (Streptomyces Fradiae)
Chloro tetracycline (Streptomycin Venezuela )
Oxytetracycline (Streptomyces rimosus)
Erythromycin(Bacillus subtilis)
(ii) Serum and vaccines vaccine serum developing immunity
in human beings serum is used for treating and controlling
disease like diphtheria. Ammonia vaccines are utilised for
checking disease like typhoid, smallpox, Cholera.

9. 6. Insect Pest Control
• Using bacteria to
control the growth of
insects
• Bacillus thuringiensis
• caterpillars
• bollworms
• corn borers

10. 7. Bioremediation
• Using microbes to clean up pollutants and toxic
wastes
• Exxon Valdez - 1989
• Genera:-
• Pseudomonas sp.
• Bacillus sp.

11. 9. Microbes form the basis of the
food chain
• Marine and fresh water microorganisms

12. HARMFUL USE OF BACTERIA
1.Reduction of soil fertility
Some denitrifying bacteria suggest bacillus denitrificans and
Thiobacillus denitrificans act upon ammonia and some other
compound in soil and release free nitrogen into the
atmosphere this amount for the loss of nutritious
material from the soil which result in reducing soil
fertility also.

13. 2.Food poisoning
Several saprophytic bacteria grow on food materials and
produce harmful toxins micrococcus bio-genes cause
poisonous poisoning of cream milk, cheese and meat
products Salmonella typhimurium
and Clostridium botulinum make food poisonous.

14. 3.Human Disease caused by
Bacteria
 Pneumonia
 Whooping Cough
 Botulism
 Typhoid Fever
 Cholera
 Syphilis
 Gonorrhea
 Tuberculosis
 Meningitis
 Tetanus
 Diarrhea

15. Plant Disease caused by Bacteria
 Citrus canker
 Leaf spot of Cotton
 Wilt disease
 Fire blight
 Soft Rot
 Paddy Blight
 Bean Blight
 Tobacco Wilt

16. Reference
• Textbook of Microbiology by R.P.Singh .
• Textbook of Microbiology by R.C. Dubey &
Maheshwari.
• Textbook of Botany by Dr. Y.D.Tyagi.

17. THANK YOU