FSTest Vibrio parahaemolyticus Count Plate (24 Tests)

Product Overview

The FSTest Vibrio parahaemolyticus Count Plate is a commercially available, single-use microbiological culture medium engineered for the rapid and reliable screening of Vibrio parahaemolyticus. Vibrio parahaemolyticus is a major foodborne pathogen typically associated with seafood and marine matrices. This advanced testing plate replaces traditional, labor-intensive agar media preparation, autoclaving, and tedious petridish pouring workflows.

By integrating a highly selective nutrient medium formula with a cold-water-soluble absorbent gel and specific enzymatic substrates, this system greatly simplifies pathogen identification. It serves as an efficient, streamlined diagnostic tool especially suitable for sanitary inspection authorities, commercial testing laboratories, and food production and processing enterprises aiming to protect their seafood supply chain.

Product Highlights & Key Benefits

· Accelerated 15-to-24 Hour Timeline: Confirms the presence of pathogenic bacteria within an optimal window of 15 to 24 hours, dramatically bypassing traditional multiple-day agar holding times.

· Enzyme-Specific Chromogenic Differentiation: Formulated with advanced specific enzymatic indicators. Typical target organisms manifest as distinctive, easily identifiable purple colonies, providing high visual counting accuracy.

· Superior Matrix Selectivity: Employs a highly selective medium base that effectively suppresses background flora. Most non-target organisms are completely inhibited from growing on the test plate.

· Pre-Sterilized & Ready to Use: Completely eliminates the boiling, cooling, and pH adjusting phases of traditional microbiology. Simply uncover the film and pipette the liquid sample directly onto the plate matrix.

· Integrated Grid Matrix for Overload Estimation: Features a standard grid layout overlaying the circular testing zone, facilitating section-by-section colony enumeration and reducing structural counting errors.

Technical Principle & Color Expression

The FSTest™ Vibrio parahaemolyticus Count Plate operates on a combination of specific growth parameters and target chromogenic substrate cleavage. The matrix integrates unique nutritive factors, selective agents to suppress non-target bacteria, a cold-water gel, and specific enzyme substrates.

During the incubation period, the specific enzymes expressed by living V. parahaemolyticus cells hydrolyze the integrated chromogenic substrate. This biochemical reduction markers colony localization by generating a stable, distinct purple color.

V. parahaemolyticus Enzymes + Chromogenic Substrates → Enzymatic Hydrolysis (Typical Purple Colonies)

• Vibrio parahaemolyticus: Appears as typical purple colonies.

• Non-Target Marine Flora: Most non-target organisms do not grow on the test plate. A few rare marine strains, such as Vibrio vulnificus and Vibrio cholerae, may grow, but their colonies appear blue and are clearly distinguishable from the purple target pathogen.

Specifications & Limit of Detection

Step-by-Step Procedure

1. Serial Dilution & Sample Treatment

·  Primary Homogenization: Weigh or measure exactly 25 mL (or g) of the target seafood or aquatic sample into a sterile sampling container or homogenizer cup containing 225 mL of sterile 3.5% sodium chloride (NaCl) solution. (Note: Utilizing a 3.5% NaCl matrix is critical for maintaining optimal osmotic parameters for marine Vibrio flora).

·  Mixing: Shake the container thoroughly or homogenize the mixture completely to obtain a uniform 1:10 sample homogenate.

2. Inoculation Workflow

· Place the V. parahaemolyticus count plates onto a flat, stable laboratory bench and uncover the top protective film barrier layer.

· Use a sterile pipette to dispense exactly 1 mL of the prepared sample homogenate slowly and evenly onto the center of the circular area.

· Lower the top film carefully and smoothly.

· Let the plate set undisturbed for about 10 seconds to allow the culture medium to solidify completely.

· Inoculate duplicate count plates for each individual sample, and ensure one blank negative control plate is included for verification.

3. Incubation Settings

· Stack the inoculated count plates together, return them to their original ziplock packaging bag, and seal it tightly.

· Place the sealed bag horizontally into the incubator with the transparent film side facing upward.

· To ensure uniform and unhindered thermal regulation across all matrices, ensure that no more than 12 plates are stacked at one time.

· Incubate at 36 ± 1°C for 15–24 hours.

Results Determination & Confirmation

· Positive Enumeration: Observe the colony characteristics. Count the typical purple colonies to determine target loads. For samples generating positive results, it is recommended to confirm the findings using other reliable confirmatory methods. If alternative methods are unavailable, perform at least a repeat test with a newly collected sample.

· Control Validity Check: If any colonies grow on the blank negative control plate, the entire testing log is deemed invalid.