Mueller Hinton Agar A1 Quality – HX-Media

Mueller Hinton Agar – HX-Media

Product Overview

Mueller Hinton Agar (MHA) is a non-selective, non-differential, and highly standardized microbiological culture medium primarily used for antimicrobial susceptibility testing (AST). It is globally recognized as the reference medium for the Kirby–Bauer disk diffusion method, as recommended by CLSI (Clinical and Laboratory Standards Institute) and EUCAST (European Committee on Antimicrobial Susceptibility Testing).

Mueller Hinton Agar supports the growth of a wide variety of non-fastidious aerobic and facultative anaerobic bacteria, including clinically important organisms such as Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Enterococcus spp., and other pathogens.

Mueller Hinton Agar is formulated with carefully controlled levels of thymidine and thymine, which are critical to prevent interference with certain antibiotics (e.g., sulfonamides and trimethoprim). It also maintains standardized concentrations of divalent cations (calcium and magnesium), which directly influence the activity of antibiotics such as aminoglycosides and tetracyclines.

The inclusion of starch in the formulation plays an essential role by absorbing toxic metabolic by-products released by bacteria, thereby preventing interference with antibiotic activity and ensuring clear zone formation.

Mueller Hinton Agar medium’s loose agar consistency and controlled depth (typically 4 mm) facilitate uniform lateral diffusion of antimicrobial agents, resulting in well-defined and reproducible zones of inhibition.

Due to its high reproducibility, consistency, and compliance with international standards, Mueller Hinton Agar is extensively used in clinical microbiology laboratories, pharmaceutical quality control, research institutions, and antibiotic development studies.

🔬 Key Features

• Standard medium for Kirby-Bauer antibiotic susceptibility testing

• Supports growth of non-fastidious bacteria

• Controlled thymine/thymidine levels for accurate antibiotic activity

• Optimized calcium and magnesium ion concentration

• Starch inclusion enhances antibiotic performance

• Ensures uniform diffusion and clear zone formation

• High reproducibility and compliance with CLSI/EUCAST guidelines

🎯 Applications

• Antimicrobial susceptibility testing (AST)

• Clinical diagnostics and infection control

• Pharmaceutical quality control testing

• Antibiotic development and research

• Routine microbiological analysis in laboratories

🧪 Composition (Typical)

• Beef Extract: 2.0 g

• Acid Hydrolysate of Casein: 17.5 g

• Starch: 1.5 g

• Agar: 17.0 g

• Final pH (25°C): 7.3 ± 0.1

🛠️ How to Use

1. Suspend required quantity of medium in distilled water.

2. Heat with constant agitation to dissolve completely.

3. Sterilize by autoclaving at 121°C for 15 minutes.

4. Cool to 45–50°C and pour into sterile Petri plates to a uniform depth of 4 mm (~25 mL per 90 mm plate).

5. Allow to solidify and dry surface before use.

6. Prepare bacterial inoculum equivalent to 0.5 McFarland standard.

7. Swab uniformly over agar surface.

8. Place antibiotic discs aseptically.

9. Incubate at 35–37°C for 16–18 hours.

10. Measure zones of inhibition in millimeters.

⏳Storage and Shelf Life

• Store dehydrated medium at 10–30°C in a dry environment

• Keep container tightly closed to avoid moisture absorption

• Protect from light and humidity

• Prepared plates should be stored at 2–8°C and used within recommended time

• Shelf life: 2–3 years (dehydrated medium)

👍 Ideal For

✔ Clinical microbiology laboratories

✔ Hospitals and diagnostic centers

✔ Pharmaceutical industries

✔ Research and academic institutions