Reference material of escherichia coli count in food|BNCC359092 |BNCC

Essential Information Related Products

Reference material of escherichia coli count in food

Subculture	Nutritional gravy medium (English name: NA/NB): beef paste 3.0g, peptone 10.0g,NaCl 5.0g, agar 20.0g (not included in liquid medium), distilled water 1.0L,pH 7.0. Sterilization at 121 ℃ for 15min. [Note] Adding 5 mgMnSO4 · H2O to culture Bacillus is beneficial to produce spores.
Subculturing	① Positive quality control bacteria: BNCC269342 ATCC25922; (2) negative quality control bacteria: none; (3) Activate and increase bacteria according to the above quality control samples, so that the absorbance of the diluent ten times of the two bacteria is in the range of 0.3~0.5; (4) Mix the two original bacteria liquid in the same volume, dilute 25,000 times, absorb 0.5mL of final diluent and put into 10mL of protective agent (quantitative bacteria protective agent), and mix well; (5) Dividing the mixed liquid into 0.4mL/Xilin bottles, pre-freezing at -80 degrees Celsius for 20-24 hours, taking out freeze-drying overnight, sealing the freeze-dried quality control products and labeling them for storage the next day;
Growth conditions	37 ℃, aerobic, 18-24h
Storage conditions	-20 ℃, kept away from light
Safety level	1
Application	Sensitive test; Antibacterial test; Food testing; Cosmetic testing; Culture control; Quality control strain; API verification bacteria, GB 4789.38-2012 Escherichia coli count positive control strain.
Sharing mode	Public welfare sharing