Goto Saki, Urase Taro, Nakakura Kaito
School of Bioscience and Biotechnology, Tokyo University of Technology, Tokyo 192-0982, Japan.
Microorganisms. 2023 Aug 23;11(9):2133. doi: 10.3390/microorganisms11092133.
Contamination with 2,4,6-trichloroanisole (TCA) often causes taste and odor (T&O) problems in drinking water due to its low odor threshold concentration. Microbial -methylation of the precursor 2,4,6-trichlorophenol (TCP) would be the dominant mechanism for TCA formation. Simple and rapid measurement of TCP in the low concentration range is necessary to control the problems induced by TCA. In this study, the combination of microbial conversion and instrumental analysis was proposed as a method of TCP quantification. Fungi and bacteria were isolated from various water samples and examined for their ability to produce TCA from TCP. As a result, a strain exhibiting quantitative TCA production and a high growth rate was obtained and named sp. CB14. The conversion rate of TCP to TCA by this strain was found to be high and stable (85.9 ± 5.3%), regardless of the applied TCP concentration, although within the range of 0.1-10 µg/L. The limits of detection and quantification for TCP by this proposed method were determined to be 5.2 ng/L and 17.3 ng/L, respectively. By improving the methods, sp. CB14 could be used for the quantification of TCP at very low concentration levels, which is sufficient to manage the T&O problem caused by TCA.
2,4,6-三氯苯甲醚(TCA)污染由于其较低的气味阈值浓度,常常导致饮用水出现味觉和嗅觉(T&O)问题。前体2,4,6-三氯苯酚(TCP)的微生物甲基化是TCA形成的主要机制。为控制TCA引发的问题,需要对低浓度范围内的TCP进行简单快速的测量。在本研究中,提出将微生物转化与仪器分析相结合作为TCP定量的一种方法。从各种水样中分离出真菌和细菌,并检测它们从TCP产生TCA的能力。结果,获得了一株表现出定量产生TCA且生长速率高的菌株,并命名为sp. CB14。发现该菌株将TCP转化为TCA的转化率高且稳定(85.9±5.3%),尽管在0.1-10μg/L范围内,且与所应用的TCP浓度无关。该方法对TCP的检测限和定量限分别确定为5.2 ng/L和17.3 ng/L。通过改进方法,sp. CB14可用于极低浓度水平下TCP的定量,这足以解决由TCA引起的T&O问题。