The present study emphasizes the biosurfactant mediated anthracene degradation by a marine alkaliphile Bacillus licheniformis (MTCC 5514). The isolate, MTCC 5514 degraded >95% of 300 ppm anthracene in an aqueous medium within 22 days and the degradation percentage reduced significantly when the concentration of anthracene increased to above 500 ppm. Naphthalene, naphthalene 2-methyl, phthalic acid and benzene acetic acid are the products of degradation identified based on thin layer chromatography, high performance liquid chromatography, gas chromatography and mass analyses. It has been observed that the degradation is initiated by the biosurfactant of the isolate for solubilization through micellation and then the alkali pH and intra/extra cellular degradative enzymes accomplish the degradation process. Encoding of genes responsible for biosurfactant production (licA3) as well as catabolic reactions (C23O) made with suitable primers designed. The study concludes in situ production of biosurfactant mediates the degradation of anthracene by B. licheniformis.

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Diet plays a major role in the body physiology and metabolism. The quantity, nature and stability of the macronutrients present in the diet have a major impact on the composition of gut microbiota. Gut microbiota plays a major role in the body metabolism and leads to obese or lean phenotype. Bacteriodetes, Firmicutes, Proteobacteria and Actinobacteria are the major microbes that inhabit in the region of the gut. We made an attempt to study the effects of Cafeteria (CAF) diets and normal chow diets on diet consumption, weight gain, metabolism and composition of gut microbiota in fecal and cecum samples from three weeks old Sprague Dawley (SD) rats (n = 18/group) using 16S rDNA high throughput sequencing. Results revealed that distinctive diet based phenotypical changes were observed in some of the Cafeteria diet fed rats. Interestingly, some weight gain resistant (WGR) animals in Cafeteria diet fed groups show similar trend like that of control normal chow fed rats. Fecal microbiome analysis indicates that the ratio of Bacteriodetes is higher than the Firmicutes in cecum samples of Cafeteria diet fed rats whereas no significant difference is found in fecal samples of Cafeteria diet fed rats and as well as in control rats. Further analysis of other taxa at the level of family and genus of microbial abundance are also discussed. Our study suggests that contribution of gut microbiota towards obesity is not at the phylum level, and microbiome composition even at the level of species or strain may exert impact on the metabolism of the Cafeteria diet.

The present study emphasizes the diversity assessment of marine Bacillus species with special reference to biosurfactant production, respective gene expression, and discrimination among Bacillus licheniformis and Bacillus subtilis. Among the 200 individual species of eastern coastal plain of Tamil Nadu screened, five biosurfactant producing potential bacterial species with entirely different morphology were selected. Biochemical and 16S rRNA gene sequence analysis suggested that all the said five species belong to Bacillus genera but differ in species levels. Biosurfactant of all the five species fluctuates in greater levels with respect to activity as well as to constituents but showed partial similarity to the commercially available surfactin. The expression of srf gene was realized in all of the five species. However, the sfp gene expression was observed only in three species. In conclusion, both B. licheniformis and B. subtilis demonstrate srf gene; nevertheless, sfp gene was expressed only by Bacillus subtilis.

Cadmium (Cd) is a toxic heavy metal that is widespread in the environment due to the substantial anthropogenic inputs from the agriculture and industrial sectors. The toxic impact of Cd adversely affects human health and is linked with endocrine disruption, carcinogenicity, diabetes-related diseases, and metabolic disorder. One of the main characterizations of Cd is bioaccumulation where its half-life reaches 40 years with an unknown biological role. Several organs were found to be targets for Cd accumulation such as the liver, kidneys, and adipose tissue. Adipose tissue (AT) is a dynamic organ that plays a significant role in the body’s homeostasis through the maintenance of energy storage. Another vital function for AT is the secretion of adipokines which provides a metabolic cross-talk with the whole body’s organs. Cd is found to adversely impact the function of AT. This includes the disruption of adipogenesis, lipogenesis, and lipolysis. As a consequence, dysfunctional AT has disruptive patterns of adipokines secretions. The main adipokines produced from AT are leptin and adiponectin. Both were found to be significantly declined under the Cd exposure. Additionally, adipose tissue macrophages can produce either anti-inflammatory markers or pro-inflammatory markers depending on the local AT condition. Cadmium exposure was reported to upregulate pro-inflammatory markers and downregulate anti-inflammatory markers. However, the exact mechanisms of Cd’s adverse role on AT structure, function, and secretion patterns of adipokines are not totally clarified. Therefore, in this review, we present the current findings related to Cd detrimental effects on adipose tissues.