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Bioremediation is the field of science that is gaining the crucial importance for the time being regarding the sustainability and survival of the mankind. It is the best of the processes for detoxification and removal of the hazardous substances that are accumulating in the environment in the course of development of our life-style. Bioremediation focuses on the principles on which our nature works. It is the process by which microorganisms like microbes, bacteria or fungi etc. degrade complex organic compounds into simpler ones. Microorganisms use the organic compounds for increasing their biomass or as part of their respiration process and in the way degrade the complex contaminants into non-toxic simpler fragments. Understanding of the underlying mechanism of functioning of microorganisms and their application in the process of remediating action are the two key factors of bioremediation. Bioremediation is nature's way of cleaning up. It is ecological as well as cost effective. The process of bioremediation have been successfully used in petrochemical plants, chemical plants, refineries, food processing plants, marine barges, truck washes, wood treating plants and in various waste management applications. It is considered worldwide as the best technique for treatment of hazardous wastes in an environment friendly manner and the way for our future sustainability. This review focuses on the basic understanding of the process of bioremediation and the different pathways with mechanistic outline. [ABSTRACT FROM AUTHOR]

Abstract Three distinct biological reactors fed with synthetic medium (UASB_Control), synthetic medium and linear alkylbenzene sulfonate (LAS; UASB_SL), and real laundry wastewater (UASB_LW) were compared using a metatranscriptomic approach to determine putative bioindicator genes and taxonomies associated to all steps of anaerobic LAS biodegradation pathway. A homemade bioinformatics pipeline combined with an R workflow was developed to perform the RNAseq data analysis. UASB_SL and UASB_LW showed similar values of LAS biological degradation (~47%) and removal (53–55%). Rarefaction analysis revealed that 1–2 million reads were sufficient to access the whole functional capacity. In the first step of LAS biodegradation pathway, fumarate reductase subunit C was detected and taxonomically assigned to the genus Syntrophobacter (0.002% - UASB_SL; 0.0015% - UASB_LW; not detected - UASB_Control). In the second step, many enzymes related to beta-oxidation were observed and most of them with low relative abundance in UASB Control and taxonomically related with Smithella , Acinetobacter and Syntrophorhabdus. For the ring cleavage step, the abundance of 6 OCH CoA hydrolase putative gene was ten times higher in UASB_SL and UASB_LW when compared to UASB_Control, and assigned to Desulfomonile and Syntrophorhabdus. Finally, the adenylylsulfate reductase, taxonomically related with Desulfovibrio and Desulfomonile , was observed in the desulfonation step with the highest relative abundance in UASB_LW. Graphical abstract Unlabelled Image Highlights • Metatranscriptomic comparison among biological reactors applied to surfactant removal • Percentages of LAS removal (~50%) were similar among the reactors. • Sequencing effort was sufficient to access the functions of the microbiomes. • Active genes detected in each step of LAS removal • Microbial active core related to LAS degradation defined and explored [ABSTRACT FROM AUTHOR]

Our aims were to compare physiological parameters from the laboratory environment (LaB) and simulated goalball games (GaM), test relationships between physiological parameters in the laboratory and game technical performance (GTP), and examine the associations between physiological and technical responses during games. Seven elite athletes from the Brazilian National Team performed in LaB environment; (i) an incremental test to determine peak oxygen consumption (O2PEAK), its corresponding speed, and peak blood lactate concentration and (ii) submaximal and supramaximal efforts to estimate maximal anaerobic contribution (AnC). In GaM condition, simulated games were also performed to determine physiological responses throughout the game, and to analyze the GTP (number of throws, defenses, recovery, and density of actions). No correlations (unclear) were found between laboratory and games analyses for O2PEAK [47.3 (17.2) vs. 25.8 (18.2) mL⋅Kg-1⋅min-1], peak blood lactate concentrations [10.2 (5.4) vs. 2.0 (0.7) mM], and total AnC [21.0 (14.0) vs. 4.8 (6.1) mL Kg-1]. O2PEAK in the laboratory condition presented very likely correlations with throw and recovery frequency in games (r = -0.87 and confidence interval [CI] = 0.41; r = -0.90 and CI = 0.35; respectively). Oxygen consumption remained above baseline while blood lactate concentration remained unchanged during the games. The very likely correlation between anaerobic alactic contribution and action density (r = 0.95 and CI = 0.25) highlights the importance of the alactic metabolism. In general, our study demonstrates that goalball can be characterized as a high-intensity intermittent effort, where athlete performance is based on aerobic metabolism predominance while determinant actions are supplied by the anaerobic alactic metabolism. Specifically, higher values of LaB vs. GaM highlighted the need for standardization of specific protocols for goalball evaluation, mainly for the reproduction of ecologically valid values. In addition, O2PEAK correlated with recovery frequency in the LaB condition, demonstrating that passive or low-intensity recovery between actions is fundamental to maintain performance.

Our aims were to compare physiological parameters from the laboratory environment (LaB) and simulated goalball games (GaM), test relationships between physiological parameters in the laboratory and game technical performance (GTP), and examine the associations between physiological and technical responses during games. Seven elite athletes from the Brazilian National Team performed in LaB environment; (i) an incremental test to determine peak oxygen consumption (O2PEAK), its corresponding speed, and peak blood lactate concentration and (ii) submaximal and supramaximal efforts to estimate maximal anaerobic contribution (AnC). In GaM condition, simulated games were also performed to determine physiological responses throughout the game, and to analyze the GTP (number of throws, defenses, recovery, and density of actions). No correlations (unclear) were found between laboratory and games analyses for O2PEAK [47.3 (17.2) vs. 25.8 (18.2) mL⋅Kg-1⋅min-1], peak blood lactate concentrations [10.2 (5.4) vs. 2.0 (0.7) mM], and total AnC [21.0 (14.0) vs. 4.8 (6.1) mL Kg-1]. O2PEAK in the laboratory condition presented very likely correlations with throw and recovery frequency in games (r = -0.87 and confidence interval [CI] = 0.41; r = -0.90 and CI = 0.35; respectively). Oxygen consumption remained above baseline while blood lactate concentration remained unchanged during the games. The very likely correlation between anaerobic alactic contribution and action density (r = 0.95 and CI = 0.25) highlights the importance of the alactic metabolism. In general, our study demonstrates that goalball can be characterized as a high-intensity intermittent effort, where athlete performance is based on aerobic metabolism predominance while determinant actions are supplied by the anaerobic alactic metabolism. Specifically, higher values of LaB vs. GaM highlighted the need for standardization of specific protocols for goalball evaluation, mainly for the reproduction of ecologically valid values. In addition, O2PEAK correlated with recovery frequency in the LaB condition, demonstrating that passive or low-intensity recovery between actions is fundamental to maintain performance. [ABSTRACT FROM AUTHOR]

A cold-resistant nitrobenzene-degrading strain was screened from river sediment. The strain was identified as Methylobacillus glycogens, which has never been reported to be capable of degrading nitrobenzene. The degradation rates of 900 μg/L nitrobenzene reached respectively 99.3% and 88.6% in 144 h under both aerobic and anaerobic environments (30 mL inoculation volume at 12 ± 0.5 °C and pH7.0 ± 0.1). When aerobically degraded, nitrobenzene was firstly oxidized into o-nitrophenol, which was further oxidized into 1,2-benzenediol, meanwhile releasing NO2-. Then the 1,2-benzenediol was metabolized through either the ortho-cleavage into succinic acid and acetyl-CoA, or meta-cleavage into pyruvic acid and acetaldehyde, as well as other small molecule substances of non-toxicity or low-toxicity, which were finally decomposed into CO2 and H2O. When anaerobically degraded, nitrobenzene was firstly degraded into aniline (C6H5NH2), which was further degraded into 4-amino benzoic acid. The benzoic acid was degraded into benzoyl, which was finally metabolized and decomposed. [ABSTRACT FROM AUTHOR]

In the Estuary and Gulf of St. Lawrence, northern shrimp ( Pandalus borealis ) and Greenland halibut ( Reinhardtius hippoglossoides ) are usually found at depths > 150 m and thus frequently inhabit hypoxic areas (18–50% saturation). The impact of a one-week exposure to different levels of dissolved oxygen (100, 40, 30, and 20% saturation) at 5 °C was evaluated in adult shrimp and juvenile Greenland halibut; the effect of acute exposure to severe hypoxia was also assessed in Greenland halibut. The activities of key enzymes involved in aerobic (citrate synthase [CS], cytochrome c oxidase [COX]) and anaerobic (pyruvate kinase [PK], phosphoenolpyruvate carboxykinase [PEPCK], lactate dehydrogenase [LDH]) pathways, and of enzymes involved in antioxidant defence (superoxide dismutase, glutathione peroxidase [GPx], and catalase [CAT]) were measured. Quantitative real-time PCR analysis was also performed in Greenland halibut. In northern shrimp exposed to chronic hypoxia, muscle CS activity decreased by ~ 40%. Muscle LDH activity was significantly reduced, with a more intense reduction in males. At the same time, hepatopancreas GPx activity increased under hypoxia, and this response was stronger in males. Overall, the results suggest the presence of a threshold above 40% saturation and higher hypoxia tolerance in males. In juvenile Greenland halibut, exposure to chronic hypoxia elicited a more wide-ranging enzymatic response than did acute exposure to severe hypoxia. Under chronic hypoxia, CS activity decreased and PK and LDH activity were respectively 46% and 57% lower than in normoxia. There were no major changes in the activity of antioxidant enzymes, but activity in normoxia was high compared to other fish species. Interestingly, the relative expression of genes coding for muscle COX (severe hypoxia), liver PEPCK (chronic), and CAT (chronic) activities were triggered in hypoxia. The absence of a corresponding change in enzyme activity makes the interpretation of these results difficult, but clearly there was a response at the transcription level. Overall, the results indicate that these two species are particularly well adapted to withstand severe hypoxia. [ABSTRACT FROM AUTHOR]