BD Terreni di coltura disidratati Difco™: R2A Agar

R2A Agar was developed for bacteriological plate counts of treated potable water. A low nutrient medium, such as R2A Agar, in combination with a lower incubation temperature and longer incubation time stimulates the growth of stressed and chlorine-tolerant bacteria.

Nutritionally-rich media, such as Plate Count Agar, support the growth of fast-growing bacteria but may suppress slow growing or stressed bacteria found in treated water. When compared with nutritionally rich media, R2A Agar has been reported to improve the recovery of stressed and chlorine-tolerant bacteria from drinking water systems.

• Recommended in standard methods for pour plate, spread plate and membrane filter methods for heterotrophic plate counts.
• Intended for use only with compromised bacteria found in treated potable water.
• Yeast extract provides a source of trace elements and vitamins.
• Peptone and casamino acids provide nitrogen, vitamins, amino acids, carbon and minerals.
• Dextrose serves as a carbon source.
• Soluble starch aids in the recovery of injured organisms by absorbing toxic metabolic by-products.
• Sodium pyruvate increases the recovery of stressed cells.
• Potassium phosphate is used to balance the pH and provide phosphate.
• Magnesium sulfate is a source of divalent cations and sulfate.
• Agar is the solidifying agent.