Bacterial breakdown of benomyl. I. Pure cultures

✍ Scribed by A. Fuchs; F. W. Vries

• Publisher: Springer Netherlands
• Year: 1978
• Tongue: English
• Weight: 569 KB
• Volume: 44
• Category: Article
• ISSN: 0003-6072
• DOI: 10.1007/bf00394306

✦ Synopsis

With different soil and water samples as inoculum and the benzimidazole fungicides benomyl (either as Benlate or as the pure compound) and thiabendazole as selective agents, a large number of, mainly fluorescent, Pseudomonas strains were isolated which nearly all were able to grow in a mineral medium with benomyl as the sole source of carbon. However, no growth occurred with any of a series of other benzimidazole compounds, viz. benzimidazole, 2-aminobenzimidazole (2-AB), thiabendazole and fuberidazole. Although benomyl--or rather its non-enzymatic breakdown product methyl benzimidazol-2-yl carbamate (MBC)--was partially degraded to 2-AB, most probably n-butylamine, which arises after splitting off of the butylcarbamoyl side chain, was the actual carbon source for the Pseudomonas isolates. When incorporated in a lactate medium, 2-AB markedly inhibited the growth of Pseudomonas spp. at a concentration of 250 microgram/ml, with complete inhibition being attained at 500 microgram/ml. For Bacillus spp. grown in liquid peptone media benzimidazole compounds were inhibitory at concentrations of 500-1000 microgram/ml, with a toxicity increasing in the order: benzimidazole less than thiabendazole less than MBC less than 2-AB.