Acetobacter Broth (Mannitol)

Intended Use

Acetobacter Broth (Mannitol) is recommended as a cultivation media for mannitol positive Acetobacter species.

Composition**

Final pH (at 25°C): 7.4±0.2

**Formula adjusted, standardized to suit performance parameters

Directions

Suspend 33.0 grams in 1000 ml distilled water. Heat if necessary to dissolve the medium completely. Dispense in test tubes and sterilize by autoclaving at 15 lbs pressure (121°C) for 15 minutes.

Principle And Interpretation

Acetic acid bacteria are found in fruits with high carbohydrate concentration, which is selective for yeasts, that produce ethanol. This ethanol forms the substrate for acetic acid bacteria and may oxidize ethanol to acetic acid (1). Various synthetic and maintenance media for Acetobacter cultures have been cited (2). A typical maintenance medium is Acetobacter Broth (2). Acetobacter Broth is formulated as per Manual of Microbiological Methods (3) and used for the maintenance of Acetobacter species utilizing mannitol (4).

Peptic digest of animal tissue, yeast extract in the medium provides nitrogen, vitamins and minerals necessary to support bacterial growth. Mannitol acts as energy source. Calcium carbonate acts as a buffer.

Quality Control

Appearance: Cream to yellow homogeneous free flowing powder

Colour and Clarity of prepared medium: Yellow coloured, clear to slightly opalescent solution in tubes

Reaction: Reaction of 3.3% w/v aqueous solution at 25°C. pH : 7.4±0.2

pH: 7.20-7.60

Cultural Response

Cultural characteristics observed after an incubation at 25-30°C for 24-48 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. Vanderzant C., Splittstoesser D. F., (Eds.), 1992, Compendium of Methods for the Microbiological Examination of Foods, 3rd Ed., APHA, Washington, D. C.
2. Asai, 1968, Univ. of Tokyo Press, Tokyo, Japan and Univ. Park Press, Baltimore, MD.
3. Manual of Microbiological Methods, 1957, Society of American Bacteriologists, McGraw-Hill Book Company, New York.
4. Catalogue of Bacteria and Bacteriophages, 1992, 18th Ed., American Type Culture Collection, Rockville, MD.