Introduction

V.parahaemolyticus is gram negative pleomorphic (curved or straight), short rods, and facultative anaerobic, bacteria which lives in salty waters. V .parahaemolyticus grows, best at pH values slightly above neutrality (7.5-8.5), Vibrio parahemolyticus has been demonstrated down to pH4.5-5.0-vehicle. Foods for out breaks are sea food, such as oysters, shrimps, crabs, lobsters, clams, and related shellfhsh, the reported incubation period for V.parahaemolyticus food poisoning varies from 2 h to 4 days though it is usually 9-25hr. illness is characterized by a profuse watery diarrhoea free from blood or mucus abdominal pain, vomiting and fever. Its infection in human usually like a self-limited gastroentritis to cholera diarhea.

Materials and Methods

Microbial tests were carried out on 30 samples from seafood products including15 different types of fishes, shrimps, crabs and shells from Chahbahar coasts, Iranian southern waters in 2005 based on microbiology reference books (1, 2, 3, 5, 4, 6) and Iranian National standard No.3306 (7).this bacteria was identified in Microbiology Laboratory of the food and drug control lab and Gilan faculty of Basic Science after surveying the samples, the specifications of the sample was entered into the Information Form. The test sample was prepared according to the said standards and after preparing the. Primary and secondary suspension inoculated to enrichment salt polymyxin broth and. enrichment alkaline saline peptone water media, and placed in the temperature of 35-37° Celsius for 7 to 8 hours.

We isolate with the use a loop of from polymyxin broth media on the selective media of triphenyle tetrazolium chloride soy triptone agar and from enrichment alkaline saline peptone water media on theTCBS (thiosulfate citrate bile sucrose agar) media. After 20-24 hours (if necessary 48 hours), the Plates are removed from the temperature of 35-37°. Then we study the suspected dark red colonies on triphenyle tetrazolium chloride Soya triptone agar and green on TCBS media and we culture them separately on the saline nutrient agar media and place in the temperature of 35-37 degrees Celsius from. 8 to 24 hrs primary tests including oxidase, gram stain and microscopic Studies are carried out on the isolated colonies. Gram negative and motile, curved, bacilli Are selected by the biochemical tests: Oxidase test (+), sucrose (-) for differential and confirmative tests. These tests include 1) culture in saline meat-yeast agar media. 2) Culture in triple sugar saline iron agar media. 3) Lysine decarboxylase identification media 4) indole identification media 5) beta galactosidase.

Results and Discussion

After culture and confirmative tests, the bacteria which had Positive oxidase, movement, glucose, aerobic growth, anaerobic growth, Lysine decarboxylase, indole and beta galactosidase. Tests and negative. Sucrose, formation of gas from glucose. Lactose and hydrogen sulphide were Identified as Vibrio parahemolyticus. At the end, Vibrio parahemolyticus Was extracted from two samples of fish (6.66%) and from other samples of fishes and crabs, shell and shrimp, V. parahemolyticus was not extracted.

Considering the existence of this bacteria in seafood products, the necessity of routine identification and educating the correct methods of separating in FOOD AND DRUG CONTROL LAB is clearly felt. The results of the present study indicate the need that these food products should undergo more strict supervision from the beginning of processing to the consumption Stage. Researches to practically attain the following results are recommended:

Determining the amount of salt needed for bacteria cleansing (according to references, the growth of this bacteria in 10 % salt is negative )

Determining the pH of the media to minimize the growth (according to references , maximum growth is in the pH of 7.6-9)

Determining the prevalence of bacteria in foodstuff and the manner of preparation through freezing crab and shrimp and preventing their re-contamination.

To find out whether the out break of Vibrio parahemolyticus in semi cooked or raw seafood is more than in fully cooked foods or not ?

Whether a full cooking of seafood before freezing is necessary for preventing their re-contamination?

Whether this bacteria is more prevalent in sea coasts and river banks or not ?

Whether the extraction of bacteria from sea sediments during the spring time and its reproduction during hot seasons increases or not whether?

Whether the contamination in seafood which have been heated a little and frozen is more or not?

References

1. Adams, MR.Moss, MO.: Food Microbiology, 2^nd, Royal Society of Chemistry ( 2000).
2. Blackburn, CW.Mcciure, PJ.: Foodborne Pathogens,Hazard, Risk Analysis and Control, CRC (2002).
3. Forbes, BA. Sahud, DF. Weissfeld, AS.: Bailey and Scotts Diagnostic Microbiology, 11^th MOSBY (2002).
4. Katzug, BG.: Basic and Clinical Pharma-cology, 6^thed, Appleton & Lang (1999).
5. Miliotis, MD.Bier, JW.: International Handbook of Fodborne Pathogens. Marcel Dekker INC (2003).
6. Wallach J.: Interpretation of Diagnostic Tests, 5^th ed, Little Brown (1992).
7. Iranian National Standard No . 3306.