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Objectives: Patients with stroke are prone to disability due to muscle hypercatabolism. We aim to review this concept based on available data on benefits of amino acid supplementation in post-stroke rehabilitation. Method: The search was performed on Medline and Embase in January 2019. Randomized controlled studies, observational studies and case reports conducted in the last 15 years on the supplementation of amino acids in post-stroke rehabilitation patients were included. Result: Amino acids prevent muscle hypercatabolism in post stroke patients by suppressing myofibrillar protein and skeletal muscle degradation. Stroke patients supplemented with amino acids led to an improvement of functional and physical performance. Discussion: Muscle protein hypercatabolism and sequestration of amino acids from skeletal muscles occur cyclically in post-stroke patients to counter each other. There is a resultant deficit of amino acids which is unmet. Amino acids have antiproteolytic effect. Its supplementation prevents muscle wasting and improves rehabilitation by promoting physical performance, muscle strength, mass, and function.

Phytoremediation using timber-yielding tree species is considered to be the most efficient method for chromium/tannery effluent-contaminated sites. In this study, we have chosen Albizzia lebbeck, a chromium hyperaccumulator plant, and studied one of its chromium detoxification processes operated by its endophytic bacterial assemblage. Out of the four different groups of endophytic bacteria comprising Pseudomonas, Rhizobium, Bacillus, and Salinicoccus identified from A. lebbeck employed in phytoremediation of tannery effluent-contaminated soil, Bacillus predominated with three species, which exhibited not only remarkable chromium accumulation ability but also high chromium reductase activity. A chromate reductase was purified to homogeneity from the most efficient chromium accumulator, Bacillus sp. DGV 019, and the purified 34.2-kD enzyme was observed to be stable at temperatures from 20°C to 60°C. The enzyme was active over a wide range of pH values (4.0-9.0). Furthermore, the enzyme activity was enhanced with the electron donors NADH, followed by NADPH, not affected by glutathione and ascorbic acid. Cu(2+) enhanced the activity of the purified enzyme but was inhibited by Zn(2+) and etheylenediamine tetraacetic acid (EDTA). In conclusion, due to its versatile adaptability the chromate reductase can be used for chromium remediation.

Twenty-six native Indian tree species that are used for the enhanced tree cover program of the forest department (Government of Tamilnadu, India) were screened for phytoremediation of tannery effluent-contaminated soil containing high chromium content. Out of 26 tree species tested, 10 timber-yielding tree species were selected for further phytoremediation monitoring. After a series of treatments with tannery effluent sludge, the chromium content was measured in the plant parts. The saplings of Acacia auriculiformis, Azadirachta indica, Albizzia lebbeck, Dalbergia sisso, and Thespesia populnea were identified as efficient bioaccumulators of chromium from Cr-contaminated soil. Acacia auriculiformis accumulates higher amounts of Cr in both the root and stem. Dalbergia sisso and T. populnea were found to accumulate higher quantity of Cr in the roots, whereas A. indica, A. richardiana, and A. lebbeck accumulate Cr in their stem. The stress response of the plant species was assessed by quantifying the antioxidative enzymes such as catalase, superoxide dismutase, glutathione reductase, and DHAR. Activity of all the enzymes was observed to gradually increase following treatment with tannery effluent sludge.

The haloalkaliphilic bacterium Micrococcus sp. VKMM 037, isolated from an effluent of the caustic soda industry, was found to produce a protease. Maximal proteolytic activity was observed in cell culture grown at 40 degrees C using 2% (w/v) glycerol, 2% (w/v) beef extract and 2% (w/v) peptone as nutrients in medium also containing 0.85 M NaCl with a pH of 10.0. An efficient purification procedure combining ammonium sulphate precipitation and Q-Sepharose ion-exchange chromatography was developed. The purified 41 kDa protease was stable in a temperature range between 20 degrees C and 60 degrees C. The protease remained active over a wide range of pH values (4.0-12.0) and NaCl concentrations (0-3.42 M) with an optimum at pH 10.0 and 0.85 M NaCl, respectively. Furthermore, the enzyme remained stable or was only marginally inhibited in the presence of various organic solvents, surfactants and reducing agents. The purified protease of Micrococcus sp. VKMM 037 efficiently removed blood stains within 40 minutes of treatment. Given the biochemical characteristics determined, this novel protease could be exploited as an additive in the detergent industry and also for the synthesis of biomolecules and the degradation of protein.

An extracellular nuclease from Bacillus firmus VKPACU-1 was multifunctional enzyme, this nuclease hydrolyzed poly U rapidly and more preferentially than the other homopolyribonucleotides. Hydrolysis of RNA this enzyme released mononucleotides in the order 5'UMP > 5'AMP > 5'GMP where as in hydrolysis of DNA the mononucleotides in the order of 5'dAMP > 5'dGMP > 5'dTMP and oligonucleotides. Uridylic linkages in RNA and adenylic linkages in DNA were preferentially cleaved by the nuclease. Nuclease produced oligonucleotides having only 3' hydroxyl and 5' phosphate termini. Present nuclease hydrolyzed RNA and DNA released oligonucleotides as major end products and mononucleotides, suggesting an endo mode of action.