A New Evaluation Method for Antibiotic-Resistant Bacterial Groups in Environment

Abstract

In the present manuscript it was presented whether spreading of antibiotic resistant bacterial groups in environment could be monitored by our newly developed method by enumerating antibiotic resistant bacterial groups in various biological wastes and composts. Although the numbers were not so high, diverse kinds of colistin resistant bacteria (25 mg · L -1 ) were included in row cattle feces (1.78 × 10 4 MPN g -1 ) and cattle feces manure (>3.84 × 10 4 MPN g -1 ). Compost originated from leftover food (>44.8 × 10 4 MPN g -1 ) and shochu lee (>320 × 10 4 MPN g -1 ) included higher numbers of chlortetracycline resistant Pseudomonas sp., (25 mg · L -1 ), and row cattle feces included higher numbers of chlortetracycline resistant Enterobacteriacea (15.7 × 10 4 MPN g -1 ), which mostly consisted from Pantoea sp. or Xenorhobdus doucetiae . Numbers of multi drug resistant bacteria, resistant to 25 mg · L -1 of ciprofloxacin, streptomycin, chloramphenicol, and ampicillin, were the highest in row cattle feces (>143.6 × 10 4 MPN g -1 ), followed by cattle feces manure (4.19 × 10 4 MPN g -1 ), and shochu lee (0.36 × 10 4 MPN g -1 ), which included diverse kinds of bacterial group. The present results indicated that higher numbers of multi drug resistant bacteria were typically found in row cattle feces, and the method was found suitable to enumerate and identify them. These results suggested that the method might become their environmental risk evaluation method.