AC Broth (Actinomycete Isolation Broth) – CAT No: AS‑1103
 
Overview
AC Broth (Actinomycete Isolation Broth) is the liquid counterpart of Actinomycete Isolation Agar, formulated for the selective enrichment and cultivation of actinomycetes such as Streptomyces, Nocardia, Actinomadura, and other rare genera. Designed for use with heavily contaminated samples (soil, plant material, sediments, compost), this medium suppresses Gram‑negative and Gram‑positive bacteria as well as fast‑growing fungi, enabling slow‑growing actinomycetes to thrive during extended incubation.
 
Applications
Selective enrichment of actinomycetes from soil and environmental samples
Pre‑cultivation prior to plating on AC Agar or other selective solid media
Isolation of antibiotic‑producing actinomycetes in screening programs
Ecological and diversity studies of actinobacteria
 
Key Features
Strong selectivity against unwanted bacteria and fungi
High recovery rate of slow‑growing and rare actinomycetes
Glycerol as a preferred carbon source for Streptomyces species
Standard medium in modern actinomycete isolation protocols
 
Composition (per liter)
Sodium Caseinate – 2.0 g
L‑Asparagine – 0.1 g
Sodium Propionate – 4.0 g
Dipotassium Phosphate – 0.5 g
Magnesium Sulfate (MgSO₄·7H₂O) – 0.1 g
Ferrous Sulfate (FeSO₄·7H₂O) – 0.001 g
 
Glycerol – 5.0 g (≈ 5 mL) (Not Included)
Antibiotics (added after autoclaving, filter‑sterilized):
Cycloheximide (Actidione) – 50 mg (Not Included)
Nystatin (optional, for heavy fungal contamination) – 50 mg (Not Included)
Final pH: 8.0–8.2 at 25 °C
 
Preparation
Dissolve 11.7 g of basal medium in 1 L distilled or deionized water.
Adjust pH to 8.1 with 1 N NaOH if required.
Autoclave at 121 °C for 15 minutes.
Cool to 45–50 °C and aseptically add filter‑sterilized antibiotics.
Dispense into sterile tubes or flasks.
 
Storage & Shelf Life
Dehydrated medium: Store below 30 °C, dry and protected from light.
Prepared broth (with antibiotics): Store at 2–8 °C; use within 2 weeks.
 
Incubation
Recommended: 25–30 °C with shaking (100–150 rpm) for 5–14 days
Extended incubation (up to 4 weeks) often required for rare genera
 
For laboratory and research use only. Not for diagnostic, medical, or food applications.