Proteases are ubiquitous enzymes that occur in various biological systems ranging from microorganisms to higher organisms. Microbial proteases are largely utilized in various established industrial processes. Despite their numerous industrial applications, they are not efficient in hydrolysis of recalcitrant, protein-rich keratinous wastes which result in environmental pollution and health hazards. This paved the way for the search of keratinolytic microorganisms having the ability to hydrolyze "hard to degrade" keratinous wastes. This new class of proteases is known as "keratinases". Due to their specificity, keratinases have an advantage over normal proteases and have replaced them in many industrial applications, such as nematicidal agents, nitrogenous fertilizer production from keratinous waste, animal feed and biofuel production. Keratinases have also replaced the normal proteases in the leather industry and detergent additive application due to their better performance. They have also been proved efficient in prion protein degradation. Above all, one of the major hurdles of enzyme industrial applications (cost effective production) can be achieved by using keratinous waste biomass, such as chicken feathers and hairs as fermentation substrate. Use of these low cost waste materials serves dual purposes: to reduce the fermentation cost for enzyme production as well as reducing the environmental waste load. The advent of keratinases has given new direction for waste management with industrial applications giving rise to green technology for sustainable development.

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There are several reports about the optimization of protease production, but only few have optimized the production of organic solvent tolerant keratinolytic proteases that show remarkable exploitation in the development of the non-polluting processes in biotechnological industries. The present study was carried with aim to optimize the production of a thermostable organic solvent tolerant keratinolytic protease Thermoactinomyces sp. RM4 utilizing chicken feathers. Thermoactinomyces sp. RM4 isolated from the soil sample collected from a rice mill wasteyard site near Kashipur, Uttrakhand was identified on the basis of 16S rDNA analysis. The production of organic solvent tolerant keratinolytic protease enzyme by Thermoactinomyces sp. RM4 was optimized by varying physical culture conditions such as pH (10.0), temperature (60°C), inoculum percentage (2%), feather concentration (2%) and agitation rate (2 g) for feather degradation. The result showed that Thermoactinomyces sp. RM4 potentially produces extra-cellular thermostable organic solvent tolerant keratinolytic protease in the culture medium. Further, the feather hydrolysate from keratinase production media showed plant growth promoting activity by producing indole-3-acetic acid itself. The present findings suggest that keratinolytic protease from Thermoactinomyces sp. RM4 offers enormous industrial applications due to its organic solvent tolerant property in peptide synthesis, practical role in feather degradation and potential function in plant growth promoting activity, which might be a superior candidate to keep ecosystem healthy and functional.

Field experiment was conducted at G.B.P.U.A.T. Pantnagar, Uttarakhand, India in rainy season of 2008 and 2009 to study the impacts of increased nitrogen doses on growth dynamics, biomass partitioning, chaffy grain and nitrogen use efficiency in 4 rice genotypes viz., Vasumati, Tulsi, Kasturi and Krishna Hamsa. Four doses (N(0), N(50), N(100) and N(200) kg N ha(-1)) of nitrogen in the form of urea were applied in 3 split. Increased trend in growth dynamics during active tillering and flowering stage, and biomass partitioning at the time of active tillering and flowering stage was observed with respect to nitrogen doses. Chaffy grain number and chaffy grain weight per 5 panicles was significantly increased with enhancing nitrogen doses and was highest for Vasumati. Nitrogen use efficiency (NUE) was increased up to N(100) kg N ha(-1) and it was declined with rising nitrogen doses (N(200) kg N ha(-1)). The highest values for NUE was achieved by rice genotype Krishna Hamsa whereas lowest by Vasumati. In addition to this, a significant correlation between nitrogen doses and growth dynamics, biomass partitioning and chaffy grain was observed. These findings suggest that growth dynamics, biomass partitioning, chaffy grain could be enhanced by the input of high rate of nitrogen fertilizer but not nitrogen use efficiency. Therefore, this study is useful to screen most N efficient genotypes which can be strongly suggested to rice growers to enhance crop yield irrespective of use of high dose of N fertilizers.

The large-scale application of organic pollutants (OPs) has contaminated the air, soil, and water. Persistent OPs enter the food supply chain and create several hazardous effects on living systems. Thus, there is a need to manage the environmental levels of these toxicants. Microbial glycoconjugates pave the way for the enhanced degradation of these toxic pollutants from the environment. Microbial glycoconjugates increase the bioavailability of these OPs by reducing surface tension and creating a solvent interface. To date, very little emphasis has been given to the scope of glycoconjugates in the biodegradation of OPs. Glycoconjugates create a bridge between microbes and OPs, which helps to accelerate degradation through microbial metabolism. This review provides an in-depth overview of glycoconjugates, their role in biofilm formation, and their applications in the bioremediation of OP-contaminated environments.

The mitigation potential of avenue tree species needs a sound understanding, especially for landscape planning or planting tree species on roadside, especially in city limits where there is huge traffic due to more number of vehicles. A preliminary study was conducted to investigate the impact of heavy traffic movement and pollution thereof on physiological functioning of Lagerstroemia speciosa trees planted on roadside in terms of carbon absorption, mitigation potential and adaptive behavior. Trees on roadside exhibited reduced carbon assimilation (36.7 ± 2.4%) and transpiration rate (42.14 ± 2.9%), decreased stomatal conductance (66.85 ± 3.87%), increased stomatal resistance (212.2 ± 11.25%), more leaf thickness (40.54 ± 3.25) and water use efficiency (9.4 ± 0.87%), and changes in lead (179.31 ± 10.24%) and proline (15.61 ± 1.92%) concentration in leaf tissues when compared to less traffic area (FRI campus). The impacts were also witnessed in the form of enhanced vapour pressure deficit of air (63.18 ± 4.94%) and leaf (45.72 ± 3.25%), and air temperature (3.2 ± 0.16%) and leaf temperature (9.0 ± 0.82%) along roadside trees. It was inferred that heavy traffic movements interrupt the physiological functioning of trees due to alteration in the surrounding environment as compared to non-traffic areas. The present study provides baseline information to further explore and identify the potential avenue tree species having significant mitigation potential and adaptive efficiency to heavy traffic movements for improving urban environment.

Plant growth promoting (PGP) rhizobacteria, a beneficial microbe colonizing plant roots, enhanced crop productivity and offers an attractive way to replace chemical fertilizers, pesticides, and supplements. The keratinous waste which comprises feathers, hairs, nails, skin and wool creates problem of solid waste management due to presence of highly recalcitrant keratin. The multi traits rhizobacteria effective to remove both keratine from the environment by producing keratinase enzyme and to eradicate the chemical fertilizer by providing different PGP activity is novel achievement. In the present study, the effective PM2 strain of PGPR was isolated from rhizospheric soil of mustard (Brassica juncea) field, Pantnagar and they were identified on the basis of different biochemical tests as belonging to Bacillus genera. Different plant growth promoting activity, feather degradation and keratinolytic activity was performed and found very effective toward all the parameters. Furthermore, the efficient strain PM2 was identified on the basis of 16s rRNA sequencing and confirmed as Bacillus cereus. The strain PM2 might be used efficiently for keratinous waste management and PGP activity. Therefore, the present study suggests that Bacillus cereus have multi traits activity which extremely useful for different PGP activity and biotechnological process involving keratin hydrolysis, feather biodegradation or in the leather industry.

Proteases have found a wide application in the several industrial processes, such as laundry detergents, protein recovery or solubilization, prion degradation, meat tenderizations, and in bating of hides and skins in leather industries. But the main hurdle in industrial application of proteases is their economical production on a large scale. The present investigation aimed to exploit the locally available inexpensive agricultural and household wastes for alkaline protease production using Thermoactinomyces sp. RS1 via solid-state fermentation (SSF) technique. The alkaline enzyme is potentially useful as an additive in commercial detergents to mitigate pollution load due to extensive use of caustic soda-based detergents. Thermoactinomyces sp. RS1 showed good protease production under SSF conditions of 55 °C, pH 9, and 50 % moisture content with potato peels as solid substrate. The presented findings revealed that crude alkaline protease produced by Thermoactinomyces sp. RS1 via SSF is of potential application in silver recovery from used X-ray films.