A Modified Selective Medium Containing Benzalkonium Chloride (BKC) for the Isolation of <i>Pseudomonas aeruginosa</i>from Raw Milk

作     者：Aylin Akoglu Evrim Gunes Altuntas Gokce Polat Yemis 

作者机构：Department of Food Engineering Faculty of Engineering University of Ankara Diskapi Ankara 06110 TURKEY Institute of Biotechnology University of Ankara Golbasi Ankara 06830 TURKEY 

出 版 物：《Food and Nutrition Sciences》 (食品与营养科学（英文）)

年 卷 期：2012年第3卷第7期

页      面：947-950页

学科分类：1002[医学-临床医学] 100214[医学-肿瘤学] 10[医学] 

主　　题：P. aeruginosa Benzalkonium Chloride (BKC) Modified Cetrimide Agar Raw Milk 

摘      要：A modified selective medium (modified Cetrimide Agar, mCA) consisting of 200 μg/mL benzalkonium chloride (BKC) was developed for the isolation of Pseudomonas aeruginosa from raw milk. Initially, a total of 55 isolates were obtained from 14 raw milk samples collected from several dairy plants in Ankara, Turkey. Among these isolates, 19 were identified as Pseudomonas aeruginosa, 28 as Pseudomonas fluorescens, 4 as Acinetobacter baumannii, 2 as Enterobacter intermedium, 1 asEnterobacter agglomerans, and 1 as Escherichia coli using Microbact biochemical test kit. BKC was chosen as a selective agent to suppress growth of competitive flora because it is very effective against a wide range of Gram-negative bacteria while P. aeruginosa is resistant. MICs (minimum inhibitory concentration) for BKC were determined by agar dilution method. The concentration of 200 μg/mL BKC inhibited competitive flora, while 90% of P. aeruginosa strains were resistant. When the results of enumeration of P. aeruginosa and other Gram (-) bacteria in Cetrimide Agar (CA) and mCA were compared, it was observed that mCA was more selective than the standard CA in preventing the growth of competitive flora especially of P. fluorescens.