The current study presents a comprehensive analysis of the potential of actinobacterium Zhihengliuella sp. ISTPL4 and different composite materials for the removal of hexavalent chromium [Cr (VI)]. Genome analysis of strain indicated the presence of several oxidoreductases which includes chromate reductase, nitrate reductase, thioredoxin, superoxide dismutase and hydrogenase are other major candidate genes. Catalytic calcite-based bio-composite material was absorbed on biochar had highest Cr removal efficiency. The main mechanism involved in Cr biosorption by this strain was explained by the Langmuir isotherm model; under equilibrium conditions the maximum adsorption was observed 49± 0.3mgg−1. Kinetic studies showed that biosorption of Cr (VI) by this strain was a rate-limiting step and followed a pseudo-second-order kinetics (R2 =0.99). SEM analysis is in line with EDX result indicating highest Cr removal by calcined biochar. MTT assay shown that the bacteria successfully convert toxic Cr (VI) to comparatively less toxic form such as Cr (III).

本研究对放线杆菌志恒氏菌的潜力进行了全面分析sp。ISTPL4和其他用于去除六价铬[Cr（VI）]的复合材料。菌株的基因组分析表明存在几种氧化还原酶，其中包括铬酸还原酶，硝酸盐还原酶，硫氧还蛋白，超氧化物歧化酶和氢化酶是其他主要候选基因。催化方解石基生物复合材料吸附在生物炭上具有最高的Cr去除效率。Langmuir等温模型解释了该菌株对铬的生物吸附的主要机理。在平衡条件下，最大吸附量为49±0.3mgg-1。动力学研究表明，该菌株对Cr（VI）的生物吸附是一个限速步骤，并遵循拟二级动力学（R2 = 0.99）。SEM分析与EDX结果一致，表明煅烧生物炭去除的铬最高。