LIST OF MICROORGANISMS INVOLVED IN FOOD CONTAMINATION:

LIST OF MICROORGANISMS INVOLVED IN FOOD CONTAMINATION:

Generally, food having more amount of nutritional compound. So, most microorganisms use our food as a source of nutrients for their own growth. The growth of microorganisms on food causes decay of the food.

Bacteria,Viruses,Fungi (Yeast and Mould),Algae and Protozoa are come under the category of microorganisms. However bacteria and fungi are important in the contamination of foods.

Bacteria:

Bacteria are unicellular, prokaryotic microorganisms. Size of bacteria are 0.5 to 1.0 mm in diameter.

Important Bacterial Genus in food contamination:

1) Acetobacter

2) Aeromonas

3) Bacillus

4) Alcaligens

5) Alteromonas

6) Campylobacter

7) Clostridium

8) Corynebacterium

9) Brevibacterium

10) Desulfotomaculum

11) Enterobacter

12) Erwinia

13) Escherichia

14) Lactobacillus

15) Halobacterium

16) Gluconobacterium

17) Klebsiella

18) Microbacterium

19) Micrococcus

20) Leuconostoc

21) Listeria

22) Propionibacterium

23) Photobacterium

24) Pediococcus

25) Mycobacterium

26) Proteus

27) Staphylococcus

28) Sporosarcina

29) Sporolactobacillus

30) Salmonella

31) Shigella

32) Pseudomonas

33) Yrsinia

34) Vibrio

35) Streptomyces

36) Streptococcus.

Note: Every Above genus having many species. Example, the Genus Escherichia having 7 species includins Eschericha coli, Eschericha albertii and the genus Salmonella having 28 species including Salmonella typhi and salmonella enterica etc.,

Important Fungi ( Mould) Genus in Food Contamination:

1) Mucour

2) Rhizopus

3) Absidia

4) Aspergillus

5) Penicillium

6) Trichothecium

7) Geotrichum

8) Neurospora

9) Botrytis

10) Trichoderma

11) Pullularia

12) cladosporium

13) Helminthosporium

14) Fusarium

Important Fungi (Yeast) Genus in Food Contamination:

1) Saccharomyces

2) Pichia

3) Candida

Important Points on Microbiology:Part---2

Important Points on Microbiology:Part---2

1) What is capsid?

The protein molecule surrounding the genetic material ( DNA or RNA) of viruses are called as capsid.

2) What is sterilization?

Sterilization is a process which destroys all microorganisms. Sterilization is a important process in microbiology.

3) What are antibiotics?

A chemical substance is produced by microorganisms and it inhibit the growth of other microorganisms. It is known as antibiotic.

4) Types of antibiotics:

There are two types of antibiotics namely,

1) Narrow- spectrum antibiotics

2) Broad-spectrum antibiotics.

5) What are Narrow- spectrum antibiotics?

Narrow spectrum antibiotics inhibit the growth of narrow range of microorganisms such as Gram-positive bacteria or Gram-negative bacteria, but not both. Example: Penicillin.

6) What are Broad-spectrum antibiotics?

Broad-spectrum antibiotics kill a wide range of microorganisms such as both Gram positive bacteria and Gram negative bacteria. Example: Tetracycline.

7) Who was first used phenol as an antiseptic?

Joseph lister.

8) What are the chemical agents used to sterilize heat sensitive materials such as plastics?

· Ethylene oxide

· Formaldehyde

· Beta propiolactone

9) What are the heavy metals used as antimicrobial agents in microbiology?

· Mercury

· Silver

10) What are the chemicals used in ointments to inhibit the growth of fungus?

· Benzoic acid

· Salicylic acid.

Antisera for E.coli O 104.

Antisera for E.coli O 104.

Thanks:

Brent Barrett,Greenwood, Indiana

salbrent@sbcglobal.net

The WHO Collaborating Centre for Reference and Research on Escherichia and Klebsiella at Statens Serum Institut suggests the use of K9 and O104 antisera for screening and confirmation of E. coli O104. Both O104 and K9 antisera are available from SSI Diagnostica

The bacterium E.coli O104:H4 has been identified as the cause of the ongoing outbreak in Northern Germany and belongs to the pathogenic group of E. coli which produces verocytotoxins (VT). VTEC strains can cause bloody diarrhoea and eventually lead to kidney failure in the form of haemolytic ureamic syndrome (HUS).

As of May 29, 15:00 CET, a total of 329 cases of haemolytic uraemic syndrome (HUS) was reported to the Robert Koch Institute (RKI) since the beginning of May 2011, including three deaths. Of all cases, 71% were female and 88% 20 years or older

http://www.ssi.dk/English/SSI%20Diagnostica/SSI%20Diagnostica%20news/2011/Use%20K9%20serum%20to%20screen%20for%20E%20coli%20O104.aspx

FDA statement on E. coli O104 outbreak in Europe

Thanks: FDA.

FDA statement on E. coli O104 outbreak in Europe

SILVER SPRING, Md., June 3, 2011 /PRNewswire-USNewswire/ -- The U.S. FDA has been in routine contact with the European Union and the U.S. Centers for Disease Control and Prevention to monitor the current outbreak of E. coli O104 and to track any illnesses in the U.S. that may be related to the outbreak.

At this time, the Robert Koch Institute, the disease control and prevention public health agency of Germany, has not yet identified the definitive source of the infectious agent causing the outbreak, but has recommended that consumers in Germany avoid raw tomatoes, cucumbers and lettuce.

To date, FDA believes that this outbreak has not affected the U.S. food supply. The FDA is constantly vigilant and consistently takes steps to increase monitoring, as appropriate, in situations such as this, to protect the U.S. food supply.

The U.S. receives relatively little fresh produce from the EU, particularly at this time of year. Due to the short shelf life of most fresh produce and the availability of growing areas in the U.S. and Central America, the EU is not a significant source of fresh produce for this country.

In response to the outbreak in Europe, as a safety precaution, FDA established certain additional import controls. FDA is currently conducting increased surveillance of fresh tomatoes, cucumbers, lettuce and raw salads from areas of concern.

"When these products are presented for import, we will sample them, and we will analyze them," said Dara Corrigan, associate commissioner for regulatory affairs, who is responsible for U.S. FDA border activities. "The FDA will not allow any products found to be contaminated to enter the U.S., and, if contamination is found, will flag future shipments for appropriate action.

Biological Warfare against Azadirachta indica ( Neem Tree)?

Biological Warfare against Azadirachta indica ( Neem Tree)?

By V.Palanivelan.

Neem is a tree and it is native to India,Burma, Bangladesh, Sri Lanka,Malaysia and Pakistan. The botanical name of Neem tree is Azadirachta indica. The seeds of neem contain a complex secondary metabolite namely azadirachtin.

All parts of a neem tree such as bark, leaf and seed having medicinal properties. Neem used as antifungal, antibacterial, antiviral agent. It also used as spermicidal agent.

Now days the mortality rate of neem trees are high. Why????????????

Is it due to climate change? Is any biological warfare against neem?

Biological warfare means the use of disease causing microorganisms to kill human, animals and plants. Is any chance to biological warfare against neem trees?

It is my doubt only. See above photos.

Photo: 1 : Fresh Neem plant.

Photo: 2 : Close-Up shot of fresh Neem leaves.

Photo:3 : Partially dead Neem Tree.

Photo: 4: Dead Neem Tree.

Important Points on Microbiology:Part---1

Important Points on Microbiology:Part---1

1) Cell theory was proposed by Robert Hooke in 1665.

2) Cells can be divided in to following two categories

Prokaryotes
Eukaryotes

3) Prokaryotes:
The prokaryotes are a group of organisms that lack a cell nucleus or any other membrane-bound organelles.
Ex.: Bacteria and Cyanobacteria

4) Eukaryote
A eukaryote is an organism whose cells contain complex structures enclosed within membranes.
Ex.: Animal cell, Plant Cell, Algae, Fungi

5) Based on chemical composition of cell wall, bacteria can be classified in to following two categories.
1) Gram positive bacteria.
2) Gram Negative Bacteria.

6) Are viruses considered either eukaryotes or prokaryotes?
Viruses are not comes under eukaryotes and prokaryotes. Viruses are acellular. It may be called as akaryotic.

7) Basic shapes of Bacteria:

Round shape --- called as Coccus.
Rod shape --- called as Bacillus.
Spiral shape --- called as Spirillum.

8) What is pleomorphic?
Some bacteria can later their shapes and occur in different shapes. It is called as pleomorphic.

9) Example for pleomorphic?
Rhizobium
Mycoplasma
Arthrobacter.


10) The first virus to be crystallized was
Tobacco mosaic virus (TMV) in 1935 by Wendell Meredith Stanley.


11) The five kingdom classification was proposed by
R.H.Whittaker in the year 1969.
12) The two components of the binomial name of microorganisms are
Genus and Species.

13) What is flagella?
Some bacteria have ability to move from one place to other by means of appendages called flagella.

14) Form of flagella:
Monotrichous: Single flagellum found on bacteria. Ex. Pseudomonas aeruginosa.
Amphitrichous: A flagellum found on each end of the cell. Ex: Aquaspirillum serpens
Lophotrichous: Multiple flagella at the end of the cells. Ex: pseudomonas fluorescens
Peritrichous : Flagella found on entire body of the cells. Ex: salmonella typhi

15) what is pili?
A hairlike appendages found on surface of many bacteria. It is called as Pili.
16) An alternative name for pili is Fimpriae.
17) What is difference between flagella and pili based on usage on bacteria?

Flagella used to move and Pili used to initially colonize host cells.

18) What is psychrophilic bacteria?
It is a type of bacteria that are capable of growth and reproduction in cold temperatures, ranging from −15°C to +10°C. Ex. Arthrobacter sp., Psychrobacter sp.

19) What is mesophilic bacteria?
It is a type of bacteria that grows best in moderate temperature, neither too hot nor too cold, typically between 25 and 40 °C. Ex. E.coli, Salmonella Sp, etc.

20) What is thermophilic bacteria?
It is a type of bacteria that are capable of growth and reproduction in high temperatures between 45 and 80 °C. Ex. Thermus aquaticus

21) What is Acidophilic bacteria?
Acidophilic bacteria are those that thrive under highly acidic conditions (usually at pH 2.0 or below). Ex. Thiobacillus acidophilus.

22) What is Alkaliphilic bacteria?
It is a type of bacteria that are capable of growth and reproduction in high pH between 9 and 11 Ex. Bacillus okhensis

23) What is Chemotaxis?
Movement of bacteria in response to chemicals is called Chemotaxis.

24) The Hereditary substance in all microorganisms is DNA.
25) Nomenclature was established by?
Carolus Linnaeus.