MacConkey agar plates are a selective and differential solid growth medium formulated with bile salts and crystal violet to inhibit Gram-positive bacteria while supporting the growth of Gram-negative bacteria. Lactose and a pH indicator, called neutral red, enable differentiation based on lactose fermentation, producing pink to red colonies for lactose-fermenting bacteria and colorless colonies for non-lactose-fermenting bacteria.

MacConkey agar plates are commonly used for the isolation and identification of Enterobacteriaceae, including E. coli, Klebsiella, Enterobacter, and Salmonella species. Because of their selective and differential properties, MacConkey agar plates are foundational media in clinical diagnostics, environmental monitoring, food safety testing, and academic or industrial microbiology R&D.

Our MacConkey agar plates are supplied as ready-to-use pre-poured plates, eliminating in-house media preparation and reducing variability across workflows. As selective and differential media, our MacConkey agar plates provide clear, reproducible colony morphology and color differentiation for reliable microbial identification.

We stock a variety of ready-to-ship MacConkey agar plates, including 100 mm and 150 mm plate formats, with formulations containing levofloxacin (16 µg/mL), kanamycin (50 µg/mL), or 1% D-galactose. All our plates are manufactured using validated processes and rigorous quality control to ensure growth performance and lot-to-lot consistency. 

In addition to standard formulations, we also offer custom manufacturing services with industry-leading turnaround times. Custom options include modified MacConkey formulations, antibiotic combinations, and specialized plate formats to support specific clinical, industrial, or research applications.