Alkaline Saline Peptone Water (ASPW) – CAT No: AS‑1106
 
Overview
Alkaline Saline Peptone Water (ASPW) is a highly selective enrichment broth designed for the isolation of Vibrio parahaemolyticus and other halophilic Vibrio species from seafood, marine environments, and clinical samples. The combination of high alkalinity (pH 8.4–8.6) and elevated salinity (2–3% NaCl) creates optimal conditions for pathogenic marine vibrios while strongly inhibiting terrestrial and enteric bacteria.
ASPW is the preferred enrichment medium in the FDA Bacteriological Analytical Manual (BAM) and ISO 21872‑1 for V. parahaemolyticus detection.
 
Applications
Primary enrichment of Vibrio parahaemolyticus from shrimp, oysters, crabs, and other seafood
Isolation of halophilic vibrios (V. vulnificus, V. alginolyticus, V. mimicus) from estuarine and coastal waters
Food‑safety monitoring and outbreak investigations of seafood‑borne vibriosis
Recommended first‑step enrichment before plating on TCBS Agar or CHROMagar™ Vibrio
 
Key Features
High alkalinity + elevated salinity = excellent selectivity for marine pathogenic vibrios
Faster and higher recovery of V. parahaemolyticus compared to standard APW
Globally standardized and validated medium (FDA‑BAM, ISO 21872‑1)
Simple two‑component formulation for ease of preparation
 
Composition (per liter)
Peptone (bacteriological or tryptone) – 20.0 g
Sodium Chloride (NaCl) – 20.0 g (validated protocols may use 20–30 g)
Final pH: 8.5 ± 0.2 at 25 °C
 
Preparation
Dissolve 40 g od medium in ~950 mL purified water.
Adjust volume to 1 L and mix thoroughly.
Heat if necessary to dissolve the medium completely. 
Adjust pH to 8.5 with 1 N NaOH if required.
Dispense into tubes or bottles (typically 10 mL per tube).
Autoclave at 121 °C for 15 minutes.
Cool to room temperature before use.
 
Storage & Shelf Life
Prepared ASPW: Store at room temperature (protected from light) for up to 3 months, or at 2–8 °C for extended shelf life.
Do not use if pH drops below 8.2.
 
Incubation
35–37 °C for 6–18 hours (overnight)
Turbidity typically visible within 6–8 hours in contaminated samples
 
For laboratory and research use only. Not for diagnostic use without proper validation.