By releasing of azo dye through textile effluent, textile industry is the main cause of water pollution resulting into acute effect on environment and human health. Development of any eco-friendly and cost-effective method that may address the drawbacks to physical or chemical methods of dye removal is the recent global priority. Physical or chemical methods for textile wastewater pretreatment are of high cost, extremely energy consuming, and environmentally low efficient and generate toxic sludge. Thus, the use of microbial technique for textile dye degradation will be eco-friendly and is probably a lucrative alternative to physico-chemical processes. Microbial enzymes, viz. laccase and azoreductase, are cost-efficient, easy to harvest, easily downstream processable, and effortlessly mobilizable. Recent research trends on nanoparticle-microbial enzyme conjugates are also highly efficient to remove the azo dye from textile waste within a few minutes. But unfortunately, due to some gap between academia and industry, these methods remain only limited up to laboratory and its industrialization is still a challenge. The present review is an illustrated compilation of the use of microbial enzymes in removal of textile dyes.

Pure and drinkable water will be rarer and more expensive as the result of pollution induced by industrialisation, urbanisation and population growth. Among the numerous sources of water pollution, the textile industry has become a major issue because effluents containing dyes are often released in natural water bodies. For instance, about two years are needed to biodegrade dye-derived, carcinogenic aromatic amines, in sediments. Classical remediation methods based upon physicochemical reactions are costly and still generate sludges that contain amine residues. Nonetheless, recent research shows that nanomaterials containing biopolymers are promising to degrade organic pollutants by photocatalysis. Here, we review the synthesis and applications of biopolymeric nanomaterials for photocatalytic degradation of azo dyes. We focus on conducting biopolymers incorporating metal, metal oxide, metal/metal oxide and metal sulphide for improved biodegradation. Biopolymers can be obtained from microorganisms, plants and animals. Unlike fossil-fuel-derived polymers, biopolymers are carbon neutral and thus sustainable in the context of global warming. Biopolymers are often biodegradable and biocompatible.

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The exopolysaccharide succinoglycan is produced mainly by a large number of soil microbes of , or genera etc. Structural properties of succinoglycan are unique in terms of its thermal stability and superior viscosifying property. Unlike the other highly commercialized bacterial exopolysaccharides like dextran or xanthan, mass scale application of succinoglycan has not been that much broadly explored yet. Bacterial succinoglycan is found suitable as a viscosifying and emulsifying agent in food industry, in gravel packing or fluid-loss control agent etc. In this present review, the key aspects of succinoglycan study, in particular, developments in structural characterizations,/ operon system involved in biosynthesis pathway, commercial applications in food and other industries and patenting trends have been discussed.

Xylans are the second most abundant form of hemicelluloses and are the second most abundant polysaccharide in nature after cellulose. To degrade xylan, microbes produce mainly xylanase enzyme. Wide range of microorganisms like fungi, bacteria, yeast, marine algae etc. are capable of producing xylanase. Main source of xylanase is fungi but industrial production of bacterial xylanase is low cost, easy downstream process and high production rate. To understand primary, secondary and tertiary structure of xylanase, in silico composition of amino acids, basic physiological characteristics; viz ., pI, molecular weight, instability index, GRAVY, molar extinction coefficient, secondary structure, presence of functional domain and motifs, phylogenetic tree, salt bridge compositions are determined. In silico study of xylanase focused on 36 different bacterial sources are performed by retrieving FASTA and PDB sequences using RCSB PDB. FASTA and PDB files are proceed further in ExPASy-ProtParam, RAMPAGE, QMEAN, MEME, PSIPRED, InterProScan, MOTIF scan, ERRAT, Peptide cutter, ESBRI and MEGA 7. The instability index range (16.90–38.78) clearly indicates that the protein is highly stable. α- helix mean value (27.11%) infers the protein is dominated by α- helix region. The aliphatic index (39.80–90.68) gives information that the protein is highly thermostable, prevalence by alanine amino acid in aliphatic side chain. No transmembrane domain was found in the protein which confirms the enzyme is extracellular in nature. Ancestor chart analysis confirmed that it is a part of carbohydrate metabolic process and more specifically a member of glycoside hydrolase super family.

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Biodiversity is measured at different levels of biological set up together with genes, species and ecosystems along with their interactions. There are a total of 34 biodiversity hotspots in the world, among which the Eastern Himalayan (EH) range is one of the richest with nearly 750,000 sq. km area covering Nepal, Bhutan, and the Indian states of West Bengal, Sikkim, Assam and Arunachal Pradesh, southeast Tibet (China) and northern Myanmar. Among these countries, Bhutan is the only one sharing all its land area as the EH region occupying a major share of 7.60% of the total EH area. Bhutan is part of 23 important bird areas, 8 ecoregions, important plant areas and wetlands with 2 Ramsar areas-Tashiyangtse and Wangdue. It is also among the exclusive biodiversity hotspots in the world where forest coverage has increased above 72% of the country's total area. The country is gifted with enormous forest cover of 70.46% of the total land part. It also has 10 protected areas (PAs) with biological corridors that are home to mass populations of vulnerable Takin, endangered one-horn rhino, pigmy hog, leopard, red panda, etc. and also varying bird species. Bhutan also has many hot-water springs which are believed to have medicinal properties to cure diseases. The EH is now experiencing widespread warming higher than 0.01C per year. Due to global warming, slow melting of the EH glaciers may cause huge floods in Bhutan in future resulting into loss of keystone species. India may also be affected by these future floods. In order to achieve sustainable development using this unique biodiversity hotspot, management of PAs, use of non-timber products and less urbanization are required.

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