This study aimed to evaluate the kinetic parameters in methane production and the biodegradation of standard LAS and LAS from laundry wastewater with different inocula in anaerobic batch reactors.. Kinetics of methane production and biodegradation of linear alkylbenzene sulfonate from laundry wastewater

The aim of this study is to evaluate through kinetic parameters the methane production and the biological degradation of standard linear alkyl benzene sulfonate (LAS) (50±3.5 mg/L - Phase II) and LAS from laundry wastewater (85±2.1 mg/L - Phase III) in batch reactors with anaerobic biomass from different sources. For mesophilic biomass from poultry slaughterhouse (SGH) the highest cumulative methane productions in Phases II and III were 1,844.8±149 µmol 1,237.8±60 µmol respectively. In the same phases, methane production rates of 70.8±88 µmol/h and 4.01±07 µmol/h were observed and a lower lag phase was observed in both phases. The use of thermophilic biomass from sugar cane processing plant (THF) under incubation at 30°C was not favorable for methane production and biodegradation for both conditions of surfactant. However, with this biomass the highest kinetic coefficient degradation (K1app) was obtained in Phase II (0.33±0.3 h-1) compared with mesophilic biomass (0.13±0.02 h-1). Therefore, the standard LAS as well as LAS from laundry wastewater influenced in kinetics of methane production and in the activity of organic matter degradation. A next-generation, Illumina-based sequencing approach was employed to characterize the bacterial and archaeal community from SGH II and III where were found 108 and 7 genera, respectively, for both samples, responsible for the degradation of the anionic surfactant LAS.

本研究旨在通过动力学参数（kinetic parameters），评估不同来源厌氧微生物菌群（anaerobic biomass）的分批式反应器（batch reactors）中，标准直链烷基苯磺酸盐（linear alkyl benzene sulfonate, LAS）（50±3.5 mg/L——第二阶段）与洗衣废水（laundry wastewater）中提取的LAS（85±2.1 mg/L——第三阶段）的甲烷生成（methane production）量与生物降解（biological degradation）效果。对于家禽屠宰场（poultry slaughterhouse）来源的嗜温厌氧微生物菌群（mesophilic biomass, SGH），第二、第三阶段的最高累积甲烷生成量分别为1844.8±149 μmol与1237.8±60 μmol。在上述两个阶段中，测得的甲烷生成速率（methane production rates）分别为70.8±88 μmol/h与4.01±07 μmol/h，且两个阶段均观察到更短的滞后期（lag phase）。采用来自甘蔗加工厂（sugar cane processing plant）的嗜热厌氧微生物菌群（thermophilic biomass, THF）在30℃下进行恒温培养（incubation）时，对于两种表面活性剂条件下的甲烷生成与生物降解均无促进效果。不过相较于嗜温厌氧微生物菌群的表观降解动力学系数（K1app）为0.13±0.02 h⁻¹，该菌群在第二阶段获得了最高的表观降解动力学系数（0.33±0.3 h⁻¹）。因此，标准LAS与洗衣废水中的LAS均会对甲烷生成动力学以及有机物降解活性产生影响。本研究采用基于Illumina平台的下一代测序技术（next-generation sequencing），对SGH第二、第三阶段的样品进行细菌群落（bacterial community）与古菌群落（archaeal community）表征，结果显示两份样品中分别存在108个与7个属（genera）水平的微生物类群，负责阴离子表面活性剂（anionic surfactant）LAS的降解。