Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, Punjab, India.
Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar, Punjab, India.
J Appl Microbiol. 2021 Sep;131(3):1274-1288. doi: 10.1111/jam.15045. Epub 2021 Mar 2.
The objectives of the present study were to explore the benzyl butyl phthalate (BBP) and dimethyl phthalate (DMP) degradation potential of Bacillus marisflavi RR014 isolated from the tap water of public toilet and also to optimize the phthalates degradation process using response surface methodology.
The minimal salt medium was used for the biodegradation analysis of phthalates. The quantification of phthalates and their intermediate metabolites identification were done by using UHPLC and LC-MS/MS respectively. The results revealed that B. marisflavi RR014 is capable of degrading both the phthalates under varying pH, temperature and salinity conditions. The formation of phthalic acid from the breakdown of BBP and DMP (500 mg l ) in the medium was observed after 24 h. After 72 h, 61% of BBP and 98·9% of DMP in the medium was degraded as monitored by UHPLC. The identification of intermediate metabolites by LC-MS/MS revealed that hydrolysis of BBP and DMP produces phthalic acid.
The degradation rate of both the phthalates was increased as the parameters increased up to an optimum level. The three environmental factors (pH, temperature and salt concentration) strongly affect the rate of degradation of both the phthalates. The maximum degradation rate for both the phthalates was achieved at pH 7, temperature 35°C and salt concentration of 1% as observed from the central composite experimental design.
It is the first report on the phthalates biodegradation potential of B. marisflavi RR014 isolated from the tap water of public toilet. The bacterium is capable of degrading BBP and DMP under varying pH, temperature and salinity, therefore, ideal to treat the phthalate contaminated environments.
本研究旨在探索从公共厕所自来水分离出的海栖热袍菌 RR014 对邻苯二甲酸丁基苄基酯（BBP）和邻苯二甲酸二甲酯（DMP）的降解潜力，并采用响应面法优化其降解过程。
采用最低盐培养基进行邻苯二甲酸的生物降解分析。采用 UHPLC 和 LC-MS/MS 分别定量分析邻苯二甲酸及其中间代谢产物的鉴定。结果表明，B. marisflavi RR014 能够在不同 pH 值、温度和盐度条件下降解这两种邻苯二甲酸。在 24 h 后，观察到 BBP 和 DMP（500 mg/L）在培养基中分解生成邻苯二甲酸。72 h 后，UHPLC 监测到培养基中 61%的 BBP 和 98.9%的 DMP 被降解。通过 LC-MS/MS 鉴定中间代谢产物表明，BBP 和 DMP 的水解产生邻苯二甲酸。
随着参数的增加，两种邻苯二甲酸的降解率均增加，直至达到最佳水平。三个环境因素（pH 值、温度和盐浓度）强烈影响两种邻苯二甲酸的降解速率。从中心组合实验设计观察到，两种邻苯二甲酸的最大降解速率均在 pH 值为 7、温度为 35°C 和盐浓度为 1%时达到。
这是首次报道从公共厕所自来水分离出的海栖热袍菌 RR014 对邻苯二甲酸丁基苄基酯和邻苯二甲酸二甲酯的生物降解潜力。该细菌能够在不同的 pH 值、温度和盐度条件下降解 BBP 和 DMP，因此是处理邻苯二甲酸污染环境的理想选择。
