Bismuth Sulfite Powder

Bismuth Sulfite Powder, Microbiological Grade

Essential Selective Agent for Salmonella Detection
Catalog Number: ASC-1025

Overview

Bismuth Sulfite Powder is a high-purity microbiological selective agent used in the formulation of Bismuth Sulfite Agar (BSA) and related selective media for the isolation and detection of Salmonella species, particularly Salmonella Typhi.

Its strong inhibitory effect suppresses competing Gram-positive organisms and many Gram-negative bacteria, while allowing Salmonella to grow and express characteristic black or metallic-sheen colonies due to hydrogen sulfide production. This makes Bismuth Sulfite Powder an essential component in clinical, food, and environmental microbiology laboratories focused on enteric pathogen detection.

Key Features

• Highly selective for Salmonella spp., especially S. Typhi

• Suppresses competing background flora

• Microbiological grade for consistent, reproducible results

• Critical component of Bismuth Sulfite Agar (BSA)

• Enhances colony contrast and interpretability

Chemical Information

• Chemical Name: Bismuth(III) sulfite oxide

• Molecular Formula: Bi₂(SO₃)₃

• Molecular Weight: 658.14 g/mol

• CAS Number: 71896-27-0

• Appearance: Fine greyish-white powder

• Solubility: Slightly soluble in water; soluble in mineral acids

Applications

Food & Beverage Microbiology

• Detection of Salmonella contamination in poultry, dairy, meats, and processed foods

• Supports compliance with food safety and regulatory testing standards

Clinical Microbiology

• Isolation of Salmonella Typhi and other Salmonella spp. from clinical specimens

• Useful in diagnostic and reference laboratories

Environmental & Water Testing

• Monitoring of Salmonella in drinking water, wastewater, and environmental samples

• Verification of sanitation and hygiene effectiveness

Culture Media Preparation

• Formulation of Bismuth Sulfite Agar (BSA)

• Use in selective media development and custom formulations

Principle of Action

• Bismuth salts inhibit competing bacteria

• Sulfite interacts with hydrogen sulfide produced by Salmonella

• Results in black or metallic-sheen colonies, providing clear visual differentiation

This selective mechanism improves detection accuracy and reduces false positives.

Usage Guidelines

Media Preparation

• Accurately weigh Bismuth Sulfite Powder according to the media formulation

• Prepare basal medium separately

Heat Sensitivity

• Do not autoclave finished media containing bismuth sulfite

• Add Bismuth Sulfite Powder aseptically to cooled (≤50 °C) sterilized base

Storage & Stability

• Store in a cool, dry place, protected from light

• Keep container tightly closed to prevent moisture uptake

• Use before expiry date indicated on the label

Intended Use

For laboratory, food, water, environmental, and research microbiology use only.
Not intended for therapeutic or direct diagnostic use in humans or animals.

Quality & Compliance

• Microbiological grade manufacturing

• Suitable for ISO, FDA-BAM, and APHA-aligned Salmonella workflows

• Certificate of Analysis (COA) available

• Safety Data Sheet (SDS) available upon request