Lecithin Tween 80 Nutrient Agar for Total Bacterial Count in Cosmetics
Lecithin Tween 80 Nutrient Agar is a nutrient medium with neutralizers, designed for the total aerobic bacterial count test of cosmetic products. It can neutralize multiple types of preservatives in cosmetics to achieve accurate bacterial counting.
Formula Composition (per Liter)
| Ingredient |
Content |
| Peptone |
20.0 g |
| Sodium chloride |
5.0 g |
| Beef extract powder |
3.0 g |
| Lecithin |
1.0 g |
| Tween 80 |
7.0 g |
| Agar |
15.0 g |
| Final pH |
7.2 ± 0.1 at 25 ℃ |
Inspection Principle
Peptone and beef extract powder supply carbon, nitrogen sources, vitamins and growth factors for bacteria. Sodium chloride maintains osmotic balance. Lecithin and Tween 80 serve as neutralizers and emulsion dispersants. Lecithin neutralizes quaternary ammonium salts; Tween 80 neutralizes phenols, hexachlorophenols and formalin. The combination of lecithin and Tween 80 can neutralize ethanol. Agar acts as the gelling agent of the medium.
Directions for Use
Weigh 48.0 g of this product, heat and dissolve in 1000 mL distilled water, dispense into containers, autoclave at 121 ℃ for 20 minutes, and reserve for later use.
Microbial Performance Test for Lecithin Tween 80 Nutrient Agar
Prepare the medium following the instructions. Inoculate the specified quality control strains and incubate aerobically at 36 ± 1 ℃ for 48 ± 2 hours.
