Development of a novel selective medium for the isolation and enumeration of acetic acid bacteria from various foods

Acetic acid bacteria (AAB) are gram-negative, obligate aerobic bacteria that produce acetic acid from alcohols or sugars. AAB are ubiquitous and found in many food products, including vinegar and wine. Owing to the lack of a suitable selective culture medium and the fastidious nature of AAB in food samples, ecological studies have been fundamentally limited for decades. Here, we developed a novel selective medium (AAB-selective agar; ABS) for AAB from food samples and evaluated its performance in comparison with glucose-yeast extract-calcium carbonate agar (GYC). In inclusivity tests, 16 species of AAB showed good growth on both ABS and GYC. Remarkably, the growth of 21 non-AAB strains was inhibited on ABS but not on GYC, suggesting the high exclusivity of the novel selective medium (p