CASOB Medium (Inactivator Broth)

Inactivator Broth is recommended for neutralizing and determining bactericidal activity of quaternary ammonium compounds.

Composition**

Final pH ( at 25°C): 7.3±0.2

**Formula adjusted, standardized to suit performance parameters

Directions

Suspend 35.0 grams in 1000 ml distilled water. Heat to boiling to dissolve the medium completely. Sterilize by autoclaving at 15 lbs pressure (121°C) for 15 minutes.

Principle And Interpretation

Inactivator Broth is recommended for neutralizing and determining bactericidal activity of quaternary ammonium compounds in products of sanitary importance, water miscible cosmetics, products containing antimicrobials or preservatives.

This medium contains casein enzymic hydrolysate and papaic digest of soyabean meal which provides necessary nitrogenous sources and other nutrients required for microbial growth. Soya Lecithin acts as neutralizing component (1). Histidine and Cysteine acts as a reducing agent.

Quality Control

Appearance: Cream to yellow homogeneous free flowing powder

Colour and Clarity of prepared medium: Light yellow slightly opalescent solution without any precipitate.

Reaction: Reaction of 3.5% w/v aqueous solution at 25°C. pH : 7.3±0.2

pH: 7.10-7.50

Cultural Response

M1706: Cultural characteristics observed after an incubation at 35-37°C for 18-24 hours.

Storage and Shelf Life

Store below 30°C in tightly closed container and the prepared medium at 2 - 8°C. Use before expiry date on the label.

Reference

1. British Pharmacopoeia ,2007, The Stationery Office British Pharmacopoeia.