A novel strain of m-cresol-degrading bacterium, named as Lysinibacillus cresolivorans, was isolated from aerobic sludge from a coking wastewater treatment plant. This bacterium is able to utilise m-cresol as its sole source of carbon and energy. The optimal pH for growth is 6.8 ~ 7.3 and the optimal temperature is 35°C. Compared to organic nitrogen sources, inorganic nitrogen sources were easily utilised for the m-cresol biodegradation. The degradation rate of m-cresol at different starting concentrations was analysed with zero-order kinetic characteristics. When the initial concentration of m-cresol was 224.2 mg•ℓ-1 , the reaction rate reached a maximum at 46.80 mg•(ℓ•h)-1 .The cell growth kinetics was also investigated with initial m-cresol concentrations varying from 0 to 1 200 mg•ℓ-1. The growth kinetics was well described by the Haldane kinetic models. The parameter values of m-cresol on cell growth were μ max = 0.89 h-1 , K s = 426.25 mg•ℓ-1 , K i = 51.26 mg•ℓ-1. Experiments supplementing growth with glucose indicated that this substrate increased the biomass, and also induced the biodegradation of m-cresol. From the results, it can be concluded that Lysinibacillus cresolivorans is an efficient m-cresoldegrading bacterium and that glucose plays multiple roles in the co-substrate condition.

Abstract. Toxic micropollutants in rainwater challenge the effective reuse of rainwater. This study proposed the application of newly developed vacuum-ultraviolet (VUV) in the advanced treatment of rainwater, and assessed the efficiency and feasibility in application. The VUV was generated from the UV lamp made of the new special silica. Benzoic acid, p-hydroxyl benzoic acid, bisphenol A, p-chlorobenzoic acid, nitrobenzene, and p-chloronitrobenzene were selected as target compounds. Their degradation efficiency was evaluated, and the degradation kinetics were also analyzed. Influence of pH was investigated, and the degradation mechanisms were explored by distinguishing the individual contributions of different radicals involved. The efficiency of VUV was further compared with that of H 2 O 2 /UV process, and its advantages were consequently discussed when applied in the practical rainwater treatment. The results obtained here will support the VUV irradiation as an promising treatment process for the purification of rainwater for the centralized and decentralized systems to guarantee the safety of the rainwater reuse. IntroductionOur world suffers from an increasing water crisis because of the climate change, anthropogenic water pollution [1][2][3][4]. Besides stringent wastewater treatment prior to drainage to environment and development of new and effective water treatment methods to guarantee the safety of water use, exploration and full utilization of new water resources are promising [1,5]. From the point of view of water circulation globally, in essence, rainwater or storm water is the origin of fresh water. So rainwater harvesting and utilization is a promising approach to alleviate the water crisis [6][7][8][9][10].Rainwater can be used for many purposes, such as irrigation in agriculture, landscape, toilet flushing, firefighting, and even drinking water. Because the pollutants released from industrial factories, traffic, etc. in various areas to atmosphere, inorganic ions and especially the toxic organics (e.g., nitrobenzene and phenols) exist in the rainwater all over the world, in addition to the micro and macro particles and microbes [11][12][13][14]. Most of those toxic organic pollutants are volatile and even recalcitrant, and thus they indeed challenge rainwater utilization. Hence, advanced purification of rainwater is central to guarantee the safety of its wide utilization.Most of the current strategies including coagulation, membrane filtration, adsorption, biodegradation, oxidation, and chlorine and UV disinfection are limited to some extent in practical application and should be selected and applied case on case [15]. The rainwater is usually unevenly distributed globally and annually. Furthermore, the rainwater compositions are also dependent upon the location-specific chemicals released there. Different purpose of rainwater utilization also needs special treatment highly depending on the costs. Advanced oxidation processes (AOPs) are attractive for the generation of very powerfully oxidizing ...

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