AS 5013.18:2010 pdf free download – Food microbiology Method 18: Examination for specific organisms—Vibrio parahaemolyticus

AS 5013.18:2010 pdf free download – Food microbiology Method 18: Examination for specific organisms—Vibrio parahaemolyticus.
3 PRINCIPLE
Two sequential liquid selective enrichments and solid selective media arc used for the isolation of presumptive V. parahacinolvticus and for their subsequent biochemical confirmation.
NOTE: A flow diagram of the examination procedure is shown in Appendix A.
4.1 General
The formulations for culture media and reagents specified in this Clause are given in Appendix B. The culture media listed in Clause 4.3 require an appropriate addition of sodium chloride to provide a concentration of 30 gIL NaCI after sterilization.
4.2 Media
4.2.2 Thioxulfate citrate bile-sails sucrose (TCBS agar
4.2.3 Sail tolerance media—containing 0 g/L. 80 g/L and 110 g/L NaCI.
4.2.4 Decarho’lase broth base (Mod/er s) and decarhoxvlase broths containing lvsine. orujlhine’ and arginine- —with 10 gIl. NaCI added.
4.2.5 Physiological saline
4.2.6 V. paruhaemolviicus preservation niediuni
4.3 Media containing 30 gIL sodium chloride (see Clause 4.1)
4.3.1 Trvpione waler— containing 30 gIL NaCI.
4.3.2 Buffered glucose hrolh—containing 30 g/L NaCI.
4.3.3 Nutrient agar—containing 30 gIL NaCI.
4.3.4 Triple sugar iron (TN!) agar—containing 30 g/l. NaCI.
4.3.5 Broincresolpurple ceilobiose broth -containing 30 g/L NaCI.
4.3.6 Peptone solution. 0.I%—containing 30 gIL NaCI.
4.4 Reagents
4.4.1 Voges-Pro,ckauer reagents
BI.3 Salt tolerance media
Ref. SA K A ZAK I, R. In RI EM ANN. Ii arid B RYAN, F. L. Food-borne Infections and Intoxications, ,md ed. New York: Academic Press. 1979.
Peptone 10.0 g
Sodium chloride 0 g. 80 g or 110 g
Water I.OL
I)issoke the peptone and the amount of sodium chloride to give the desired sak concentration in the water and adjust to p11 7.6 0.l. Dispense as required and autoclave at 121°C for 15 mm.
111.4 J)ecarhoxvlase broth (Moeller’s)
Ref. GERHARDT, P., ci a!. Manual of Methods for Genera! Bacteriology. Washington. USA: American Society for Microbiology. 1981.
B1.4.1 General
This medium must contain 10 gIL sodium chloride when used for the identification of V. paruhaemo!viicus. If commercial dehydrated medium is used, the formulation should be checked and the appropriate amount of sodium chloride added.
111 .4.2 Preparatini, of complete medium
Add 10.0 g of either L-lysine dihydrochloride. L-ornithine dihydrochloride or L-arginine hydrochloride to I L of decarboxylase broth base. Mix the amino acid with the broth base and warm to dissolve. Dispense in 5 ml. quantities in 13 mm x 100 mm tubes. and steriliie at 121°C for 10 mm.
When using this medium, overlay each tube of broth, after inoculation, with a 4 mm to 5 mm layer of paraffin oil.