Simultaneous biodegradation of dimethyl sulfide and 1-propanethiol by Pseudomonas putida S-1 and Alcaligenes sp. SY1: "Lag" cause, reduction, and kinetics exploration.

Qian Li,Zeqin Tang,Dongzhi Chen,Jianmeng Chen,Jingtao Hu,Jiahui Zhang

doi:10.1007/s11356-022-19306-8

Abstract

Simultaneous biodegradation of malodorous 1-propanethiol (PT) and dimethyl sulfide (DMS) by Pseudomonas putida S-1 and Alcaligenes sp. SY1 was investigated and the interactions implicated were explored. Results showed that PT was completely degraded in 33 h, while a lag of 10 h was observed for DMS degradation alone, and the lag was even extended to 81 h in the binary mixture. Mechanism analysis found that the lag was mainly attributed to the exposure of DMS degrader (Alcaligenes sp. SY1), rather than PT metabolites and PT degrader. The exposure time and PT concentration also influenced the lag duration much. Citric acid could effectively reduce the lag. Pseudo-first-order model was proved suitable for the description of PT degradation, revealing that PT degradation could be enhanced in presence of DMS with a concentration of < 50 mg L-1. A modified Gompertz model, incorporated the lag phase, was developed for the description of DMS degradation in the mixture, revealing that DMS degradation depended on the initial PT concentration, and when the lag was not considered, PT with low-concentration could promote DMS biodegradation, while a higher concentration (> 20 mg L-1) cast negative effect.

Highlights

Volatile organic compounds (VOCs) are widely considered as major precursors for the photochemical smog and haze, imposing great threats on environment quality and human health
Results showed that PT was completely degraded in 33 h, while a lag of 10 h was observed for dimethyl sulfide (DMS) degradation alone, and the lag even extended to 81 h in the binary mixture
It is believed that the mechanism of the lag phase proposed here may inspire more rational operation to obtain superior simultaneous removal efficiency of multiple gaseous pollutants coexisted in practical situations

Summary

Introduction

Volatile organic compounds (VOCs) are widely considered as major precursors for the photochemical smog and haze, imposing great threats on environment quality and human health. As a typical kind of VOCs, volatile organic sulfur compounds (VOSCs) are highly toxic and malodorous with extremely low smell threshold, (Padhi and Gokhale 2017). They are the main composition of traditional malodor sources, i.e. waste water treatment plants, waste landfills, livestock and poultry farm etc., and closely related with pharmaceutical chemicals, petroleum refineries, papermaking and other industries (Giri and Pandey 2013; Giri et al 2014). Unknown interactions are likely to occur during their degradation processes, which may largely influence their original degradation behaviors. Chignell et al claimed that an antagonistic interaction existed between P. putida KT2440 and Bacillus atrophaeus 1942

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Results

Conclusion