MacConkey Broth
MacConkey Broth
Selective and Differential Liquid Medium for Detection of Coliform Bacteria
Product Identification
Chemical & Physical Information
Product Name: MacConkey Broth
Catalogue Number: AS-1283
Medium Type: Selective and differential liquid culture medium
Form: Dehydrated powder
Product Description
MacConkey Broth is a selective and differential liquid culture medium primarily used for the detection and enumeration of coliform bacteria in food, water, environmental, and laboratory samples. The medium is formulated with bile salts to inhibit the growth of Gram-positive organisms, enabling selective growth of enteric Gram-negative bacteria.
Lactose serves as the fermentable carbohydrate, and fermentation by coliform bacteria results in acid production. This acidification causes a colour change of the pH indicator, providing a visual indication of lactose fermentation. The presence of peptone supplies essential nitrogenous compounds to support bacterial growth.
MacConkey Broth is commonly used for presumptive coliform testing, including applications involving membrane filtration and multiple-tube fermentation techniques. As a liquid medium, it is not intended for isolation of pure cultures but is well suited for quantitative and confirmatory testing.
Principle of the Medium
Functional Components
Peptone: Provides nitrogen, amino acids, and growth factors
Lactose: Fermentable carbohydrate for differentiation of coliforms
Bile Salts: Inhibit Gram-positive bacteria, providing selectivity
pH Indicator: Detects acid production resulting from lactose fermentation
Typical Characteristics
Medium Properties
Appearance (dehydrated): Pink to light purple powder
Appearance (prepared): Red to pink solution
pH (prepared medium): Approximately 7.4 at 25 °C
Selectivity: Inhibits Gram-positive bacteria
Differential: Lactose fermentation indicated by colour change
Typical Applications
Food & Water Microbiology
Detection of coliform bacteria in food products
Water quality testing and hygiene monitoring
Environmental & Laboratory Testing
Presumptive coliform enumeration
Use in membrane filtration and multiple-tube fermentation methods
Quality Control & Research
Routine microbiological testing
Confirmation of lactose-fermenting enteric bacteria
Preparation Instructions
Medium Preparation
Suspend the required amount of dehydrated medium in demineralised water
Heat with agitation until fully dissolved
Dispense into appropriate containers or tubes
Autoclave at 121 °C for 15 minutes
Cool to room temperature before use
Storage & Stability
Storage Conditions
Dehydrated medium: Store at 15–30 °C in a dry, sealed container
Prepared medium: Store at 2–8 °C under sterile conditions
Do not use if contamination, precipitation, or colour change unrelated to fermentation is observed
Intended Use
Regulatory Statement
For laboratory research, food testing, water testing, and educational use only.
Not intended for clinical diagnosis, therapeutic use, food preparation, or veterinary applications.
Quality & Supply Assurance
Manufacturing & Documentation
Manufactured under controlled conditions
Consistent batch-to-batch performance
Certificate of Analysis (COA) available upon request
Technical support provided by Ausamics Life Science
Customs & Trade Information
Classification
HS / AHECC Code: 3821.00.00
Prepared culture media for development or maintenance of microorganisms