Dehydrated Culture Media

Harmonized Culture Media

Harmonized Culture Media as per new USP chapter 62 and the new EP chapter 6.2.13.

Microlife Harmonized media is designed for Quality control testing methods and specifications according to the new harmonized methods.


Superior Performance

Performance complies with the recommendation of the USP chapter 62 & EP 6.2.13.

State-of-the-art equipment and carefully controlled environments to ensure consistent, high-quality products made to the latest international standards.

Quality as per international standards.

Rigorous quality assurance and quality control systems ensure that media meet the technical specifications and regulatory standards that pharmaceutical microbiologists require.


Area of Application

Microlife is currently offering to all pharmaceutical customers a product portfolio meeting the requirements of the new harmonized microbial limit test methods. Sixteen products have been introduced in Microlife range.

Currently available in 500 gm packing and can be provided in 5 kg, 25 kg packs also at customer's request. Queries are appreciated for other culture media which are not mentioned in the product price list.

Requests for custom made media are entertained.

Every living organism needs the nutrition to grow and propagate in this universe, the transfer, improvement and survival of the genome is the most important function. Every living organism transfers its genome from one generation to another and improvement of the genome is a regular practice to cope up with darwinism. In this process the nutrient culture media has its critical importance. The culture media should be precisely configured and should support the organism in diversified way. A good media should have the following properties :

  • Balanced nutrition
  • Proper hydration time
  • Setting to give proper platform
  • Clarity
  • Optimum pH

Media Preparation

The preparation of culture media from dehydrated media requires accuracy and attention to preparation. The following points are included to aid the user in successful and reproducible preparation of culture media.

Dehydrated Media and Ingredients
  • Store in cool (15-30°C), dark and dry area unless otherwise specified. Note the date on which the pack is opened.
  • Check expiry (applied to intact containers).
  • Verify that the physical characteristics of the powder are typical.
Glassware and Plasticware
  • Use high quality, low alkali borosilicate glass.
  • Avoid detergent residue.
  • Check alkali or acid residue with few drops of bromothymol blue pH indicator (yellow is acidic; blue is alkali).
  • Use vessel at least 2-3 times the volume of medium.
  • Discard etched or chipped glassware.
  • Do not use etched glassware.

Use measuring devices, scales, pH meters, autoclaves and other equipment that are frequently and accurately calibrated.

  • Use distilled or deionized water.
  • pH 5.5-7.5.
Dissolving the Medium
  • Accurately weigh the appropriate amount of dehydrated medium.
  • Dissolve the medium completely.
  • Agitate the medium while dissolving.
  • Take care not to overheat. Note that media are very sensitive to overheating. Overheated media will frequently appear darker. Do not heat in a microwave.
  • The autoclave set temperature should be 121°C.
  • Routine autoclave maintenance is important. Ask manufacturer to check for hot and cold spots.
  • The recommended 15 minutes sterilization assumes a volume of 1 litre or less. Larger volumes may require longer cycles.
  • Also check your autoclave manufacturer for recommended load configuration.
  • Quantities of media in excess of two litres may require an extended autoclave time to achieve sterilization. Longer sterilization cycles can cause nutrient concentration changes and generation of inhibitory substances.

Adding Enrichments and Supplements
  • Enrichments and supplements tend to be heat sensitive.
  • Cool medium to 45-55°C in a waterbath prior to adding enrichments or supplements.
  • Ensure adequate mixing of the basal medium with enrichments or supplements by swirling to mix thoroughly.
  • Sterilized broths may be cooled to room temperature before adding enrichment.

The pH value of the reconstituted dehydrated culture media prepared with distilled, deionized or purified water (as specified) shall produce the equivalent value prescribed on the label at a temperature of 25°C. If old material is being used, it is recommended to check the pH and correct if necessary before use. pH measurement and corrections should be carried out at 25°C for liquid culture media and reconstituted solid media (Powder) culture media in molten state. For liquid media pH measurement after sterilization cycle should be carried out by cooling of the medium to 25°C.

The correction should be done by adding 1N or 0.1N hydrochloric acid or sodium hydroxide solution to a sample of known volume taken from the reconstituted culture medium. Finally after calculation, the required acid or alkali is added in the remaining prepared medium.

For Harmonized media the pH regulation should be done as per the guidelines of European Pharmacopoeia version 6.0 edition of 2008 or as per label claim.

Dispensing Media
  • Ensure gentle mixing during dispensing.
  • Cool the medium to 50-55°C prior to dispensing to reduce water evaporation.
  • Dispense quickly.
  • If using an automatic plate dispenser, dispense general purpose media before dispensing selective media.
  • Immediately recover or recap tubes to reduce the chance of contamination. Leave Petri dish covers slightly open for 1-2 hours to obtain a dry surface.
Storage and Expiry

In general, store steam sterilized plated media inverted in a plastic bag or container in a dark refrigerator for up to 1-2 weeks.

Quality Control
  • For media prepared in house, each lot of every medium must be tested.
  • Maintain Quality control organisms appropriately.
  • Maintain appropriate records.
  • Report deficiencies to the manufacturer.

Troubleshooting Guide



Safety Check list

Handling and Use
  • Read the label before opening the container.
  • Check that the product is the one required.
  • Consider the hazards and use the proper protective clothing when handling them.
  • Take care while using the product. Avoid inhalation, ingestion, and contact with skin, eyes.
  • Avoid using contaminated apparatus and instruments.
  • Seal the container after each use tightly.
  • Do not eat or Drink while working in the laboratory.
  • Wash hands thoroughly and change contaminated clothing.
  • Preferable storage temperature as mentioned on the label.
  • Store in dry and cool place without direct sunlight and well ventilated areas protected from extreme temperature and source of ignition.
  • After opening the product it should be properly stored in dry condition, after tightly capping the bottle in order to prevent clumps due to hygroscopic nature of the product. Improper storage may lead to malfunctioning of the product and hence there would be NO liability of the company.
  • Secure chemicals from unauthorized use.
  • Segregate stock to reduce hazards.
  • Inspect stocks from time to time and dispose off deteriorated materials.
  • Carefully handle the hazardous materials.

General Instructions to The Users

Sterilization Check

It's recommended to check the autoclaves regularly to ensure the performance and maintenance of the equipment. Physical measurements should be made on temperature and pressure readings. The quality and quantity of the steam must be checked including the steam and safety valves. Biological indicators of sterilization are crucial.

High temperature and prolonged exposure is the common cause of pH drift, darkening of medium, precipitation, poor gel strengths and deviation of the quality of culture medium.

Plating of Medium
  • Agar medium should be poured into plates at about 40- 45°C (in liquid state). Cooled medium (at 40-45°C) avoids the formation of condensed water in the lids of the plates. The medium should be mixed thoroughly without bubbles formation.
  • Before inoculation ensure the dry surface of the agar plate to check microbial swarming by keeping plates at 30-40°C in incubator for 15-20 min.
  • Addition of Blood is suggested for the preparation of blood agar media rather than anticoagulant. Its always advisable to use fresh blood. If stored blood (2-8°C) is used, warm it at 30-37°C in incubator to be added by sterile cooled molten agar (45-50°C) base.
Storage of Prepared Media
  • Storage of the prepared media is very crucial. It should be Stored in the moisture proof containers to prevent drying of the medium. It's important to note that unless the stability of the prepared medium is known it should not be stored for longer periods. Agar containing mediums kept on higher temperature (40-50°C) will lead to clumps formation.
  • The media with sensitive short lived ingredient/should be used within specific period of time unless discarded.
  • Agar plates should be stored at 2-8°C in airtight condition to avoid loss of moisture to prevent the crystallization of certain ingredients in the culture media.
  • Media should not be stored below 0°C as this destroys gel structures.
Disposal of Prepared Media
  • Laboratory Environment : The microbiology lab poses many dangerous microbes to humans, animals and environment; therefore the entry should be restricted to avoid any accident. Most countries have laid down their standards for handling microorganisms and accordingly categorized the laboratories to handle cultures. For the most dangerous organisms a totally contained and highly protected environment is specified. These types of Labs are categorized under biological safety markup from 1 to 4 safety level according to international guidelines. A violation of these rules and regulations is a criminal offence.
  • Personal Practices : Assure that a qualified person should handle the infectious material otherwise it may have severe consequences. All specimens and cultures should be handled properly and should not be disposed without autoclaving. User should ensure that any machinery or apparatus used and by chance contaminated must be safely disinfected or sterilized. Cultures in reusable glass vessels (e.g. conical flasks, culture test tubes, Petri dishes, glass pipettes) must first be killed in autoclave (approximately 30 minutes at 121°C).
  • Biological Safety :It should be recognized that inoculation of culture media with organisms, deliberately or accidentally leads to large numbers of organisms being produced. Such a high numbers of pathogenic organisms can be disastrous to mankind; hence they must be disposed off safely under the approved strict guidelines of biological safety and regulations.

Product Code Identification Guide


  • Abbreviations for the name of the media
  • 1st Numeric is for bacteriological medium.
  • 2nd Numeric for agar (1) / broth (2)/ agar in additional supplement (3)/broth in additional supplement (4)/ special combination in agar (5)/ special combination in broth (6) / any other combination(7).
  • 3rd Numeric is for 100 gm or 500 gm Pack Size.

Label Identification Guide

Feature & Benefit