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Immobilization of enzymes is an effective and potential technique for improving the enzyme characteristics and plays an important role in reducing the final cost of enzymatic reactions. However, the method of enzyme immobilization should be easy, cost-effective and environment friendly when applicable at industrial scale. In present study, the successful biochemical characterization of free and immobilized keratinase was evaluated. The enzyme was effectively immobilized on chitosan and chitosan grafted-β-cyclodextrin beads. Enzyme yield of immobilized biocatalyst on chitosan alone and chitosan-β-CD-E was determined to be 90 and 93% respectively. Keratinase was able to act in highly alkaline conditions (optimum pH 11) both in free and immobilized form and showed maximum enzyme activity at 70 and 75 °C respectively. The free and immobilized enzyme exhibited remarkable thermo stability at 70 °C implying that it is capable for its usage in textile industry. The storage stability and reusability of the immobilized keratinase (chitosan-E and chitosan-β-CD-E) was significantly enhanced, with 25 and 53.5% activity, respectively, retained at 4 °C after 30 days of storage. In the preliminary experiments it was found that free keratinase have the potential to improve the quality of woollen fabrics and suitable for application in textile industries.

Carbon quantum dots (CQDs) have emerged as the promising class of fluorescent nanomaterials with size ranging from 2 to 10 nm. The CQDs possess amazing properties such as good solubility, photoluminescence, high quantum yield, functional groups on surface, photostability, biocompatibility and low toxicity. CQDs are a trending topic of intense research as they are being used for a wide range of applications such as biological imaging, sensing, drug delivery and catalysis. Nowadays, the focus of researchers has shifted towards the green synthesis of CQDs from natural and environment friendly sources. The present work reports the synthesis of fluorescent CQDs from cabbage as the natural carbon source by hydrothermal method. The as-synthesized CQDs were characterized using various analytical techniques to obtain information regarding their absorption/emission spectra, chemical functionality and morphology. Further, the synthesized CQDs were explored for optical sensing of various heavy metal ions in aqueous medium. The study provides a simple and economical method of utilizing CQDs for environmental sensing applications.

Nano-based products have shown their daunting presence in several sectors. Among them, Zinc Oxide (ZnO) nanoparticles wangled the reputation of providing "next-generation solutions" and are being utilized in plethora of products. Their widespread application has led to increased exposure of these particles, raising concerns regarding toxicological repercussions to the human health and environment. The diversity, complexity, and heterogeneity in the available literature, along with correlation of befitting attributes, makes it challenging to develop one systematic framework to predict this toxicity. The present study aims at developing predictive modelling framework to tap the prospective features responsible for causing cytotoxicity in-vitro on exposure to ZnO nanoparticles. Rigorous approach was used to mine the information from complete body of evidence published to date. The attributes, features and experimental conditions were systematically extracted to unmask the effect of varied features. 1240 data points from 76 publications were obtained, containing 14 qualitative and quantitative attributes, including physiochemical properties of nanoparticles, cell culture and experimental parameters to perform meta-analysis. For the first time, the efforts were made to investigate the degree of significance of attributes accountable for causing cytotoxicity on exposure to ZnO nanoparticles. We show that in-vitro cytotoxicity is closely related with dose concentration of nanoparticles, followed by exposure time, disease state of the cell line and size of these nanoparticles among other attributes.

Despite continued destruction of human lives by snakebites, appreciable improvements in immunotherapies have not been made. We selected and characterized venom-specific single domain antibodies (sdAbs) from a constructed phage display library of camelid variable region of heavy chain of the heavy chain antibodies (VHHs). Secretory phospholipase A2-specific sdAbs neutralized venom-induced toxicity in vitro and in vivo. Such monoclonal sdAbs could serve as an alternative to help manage snakebites to save lives.

Over the last decade MXenes have become a hotspot of materials science as one of the newest 2-dimensional (2D) materials. Upon the recognition of their distinctive features (e.g., superior optical characteristics, large surface area, excellent hydrophilicity, biocompatibility, ease of surface functionalization, and high conductivity), their potential in biosensing applications has also gained considerable attention. With versatility in MXene synthesis methods and suitable etching, MXenes can be easily transformed into quantum dots, nanosheets, and MXenes composites. As such, during the last decade optical biosensing platforms-based on MXenes have emerged along with electrochemical sensors and wearable sensors built from MXenes. Herein, we present a broad perspective on the optical properties of MXenes alongside recent findings on their biosensing applications, which are based on different optical transduction principles (e.g., photoluminescence, colorimetry, surface plasmon resonance, surface-enhanced Raman scattering, and electro chemiluminescence). Furthermore, the future perspective and challenges concerning MXenes-based optical sensing techniques are discussed.

The application of ultraviolet (UV) light in the food industry has held great promise for a long time. UVC light (200–280 nm) possesses excellent germicidal properties to inactivate a wide range of microbial pathogens (e.g., bacteria, fungi, yeasts, molds, and viruses). UVC technology can be used to effectively prevent foodborne illnesses while increasing the shelf life of food without compromising its quality by reducing the microbial load. UVC radiation processing of food depends on a variety of factors such as the operational parameters of the UVC equipment, microbial characteristics, and the composition of the food. Thus, the application of UVC irradiation is an emerging non-thermal technique for the decontamination of food products. This review describes the fundamentals of using UVC radiation to inactivate pathogenic microbes for the decontamination of foods (e.g., fruit and vegetable juices, milk and dairy products, meat products, beef, and seafood). At last, the current status of international regulations is discussed along with the future challenges in this research field.

Plastic pollution has been prevalent in the world ever since its use in majority of the areas including packaging, electronic industries, building and construction, healthcare, transportation etcetera. This has lead to a constantly increasing burden on the environment which has attracted many environmentalists and scientists towards working on different ways to cope up with this threat. Many studies have been done to find out ways to naturally degrade plastics using hidden capabilities of microbes that can use these plastics as their sole carbon source. Enzymatic degradation of plastics has been thought of serving this purpose since the revelation of microbial enzymes that can act on plastic in their natural environment and because of it being a much quicker and efficient way as compared to others. This paper gives a brief review on the degradation of plastics using enzymes from various sources and future prospects related to this area of research.

Background Several recent studies have linked emissions from printing equipment with upper airway inflammation and systemic oxidative stress in healthy humans, lung inflammation in mice, and cytotoxicity, induction of inflammatory markers and epigenetic changes in human cell lines. Acute exposures have lead to upper airway inflammation and systemic oxidative stress, which for certain markers took longer than 24–36 h post-exposure to clear. Objective In this follow-up work, we determined: i) whether chronic exposures to nanoparticles from copiers lead to chronic upper airway inflammation and systemic oxidative stress; and ii) whether expression patterns of biomarkers for such stresses change during transition from acute to chronic exposures. Methods Six permanent employees from three copy centers and eleven controls participated in the study. Nasal lavage and urine samples were collected on Monday morning (pre-shift, Mo-AM) and evening (post-shift, Mo-PM), as well as at the end of the workweek (Fr-PM), over three random weeks. The matched controls were sampled over one week. Nasal lavage samples were analyzed for a panel of 14 pro-inflammatory cytokines/chemokines, inflammatory cells, and total protein. Urine samples were analyzed for 8-OH-dG , a biomarker of systemic oxidative stress. Detailed quantitative exposure assessment to airborne nanoparticles was conducted for a whole week, and included size distribution, size-fractionated aerosol collection, extensive chemical analysis, and lung burden estimates. Results The daily geometric mean total particle number concentration varied between 14,600–21,860 particles/cm 3 , 1.7–12.1 times greater than background, with maxima up to 143,000 particles/cm 3 . Mass concentration of the nanoscale fraction was in the 1–10 μg/m 3 range. Chemical composition of the nanoparticle fraction was comprised mostly of organic compounds, mixed with several engineered nanoparticles, which contributed a metal content ranging from 2 to 8% of the total particulate mass. Five out of the 14 inflammatory cytokines, namely IL-6, IL-8, TNFα, IL-1β and Eotaxin, were significantly elevated in the nasal lavage samples of the chronically exposed copier operators (p 8-OH-dG in (4.3 fold) in urine samples. Conclusion Chronic upper airway inflammation and systemic oxidative stress were documented in photocopier operators chronically exposed to nanoparticles. These findings agree with the recent toxicological literature on printer-emitted particles and medical case reports, and call for an industry-wide study of the health effects resulting from exposure to printer-emitted particles in chronically exposed workers. Inflammatory markers point to possible involvement of toll-like receptors, particularly TLR-4, oxidative stress, and the Nf-kB pathway in mediating airway tissue inflammation.

Lead (Pb) poisoning has been a scourge to the human to pose sighnificant health risks (e.g., organ disorders, carcinogenicity, and genotoxicity) as observed from many different parts of the world, especially in developing countries. The demand for accurate sensors for its detection, especially in environmental media (soil, water, food, etc.) has hence been growing steadily over the years. The potential utility of fluorescent nanosensors as an important analytical tool is recognized due to their astonishing characteristics (e.g., high sensitivity/selectivity, enhanced detection performance, low cost, portability, and rapid on-site detection ability). This review is organized to offer insight into the recent developments in fluorescent nanosensing technology for the detection of lead ions (Pb2+). To this end, different types of nanomaterials explored for such applications have been classified and evaluated with respect to performance, especially in terms of sensitivity. This review will help researchers gain a better knowledge on the status and importance of optical nanosensors so as to remediate the contamination of lead and associated problems. The technical challenges and prospects in the development of nanosensing systems for Pb2+ are also discussed.

Marine oil spills are one of the major sources of water pollution causing huge environmental damage and economic destruction. They disturbs the ecological framework of the oceans and other water bodies causing major losses to the aquatic biodiversity. The risk associated with oil spills raise a lot of policy issues on the safe transport of oil volumes. Efficient removal of these spills is an absolute necessity for the protection of the oceanic environment and life. Onshore and offshore oil response strategies with continuous monitoring systems must be applied at the spill site to minimize the harmful impacts on the environment and human health. Currently used remediation technologies are still not effective to completely restore the polluted marine environment to its normal ecology. Nanotechnology is proving to be a valuable tool in cleaning up of these oil spills or leaks in the water by utilizing magnetic nanomaterials such as functionalized super-paramagnetic iron oxide nanoparticles (SPIONs), magnetic nanocomposites and magnetic carbon nano tubes (CNTs). Functionalization of nanoparticles using different functional moieties such as organic non-polymeric and inorganic molecules, polymers and polysaccharides renders them with novel features like enhanced adsorption capacity and high oil removal efficiency. Innumerable researches have emerged in developing novel counter measures to mitigate the dangerous impacts of oil spills. The present review emphasizes the environmental impacts of major oil spills in maritime world. This work also compiles the research conducted by various researchers and scientists in the removal of the spilled oil from water using magnetic nano-adsorbents.

Rhizosphere supports the growth and activity of an enormous and diversified microbial network. Certain rhizobacteria referred to as ‘plant growth-promoting rhizobacteria’ (PGPR) can contribute towards improved plant growth and stress tolerance and are currently of great interest for sustainable agriculture. A successful PGPR is capable of establishing itself in the rhizosphere of inoculated plants. Root colonization is an essential step in the interaction amongst plant-associated bacteria and host plant and is a multifaceted phenomenon governed by various biotic and abiotic factors. In the present investigation, an isolate MT7 obtained from maize rhizosphere and identified as Bacillus sp. was tested for its ability to perform in the tomato rhizosphere. It was screened for its survival under various abiotic stresses like salt, drought, heavy metals, and temperature and found to tolerate 10% salt stress, drought stress up to -0.73 MPa (25% PEG), heavy metals like Cr, Cu, and Ni above the permissible limits and grew well from 25 to 45 °C. The bacterial culture was verified for various other plant growth-promoting traits. It expressed chemotactic behavior and good biofilm-forming potential in the presence of tomato root exudates. Profuse colonization was observed on the tomato roots. Efficacy of the bacterial culture in the tomato rhizosphere was evaluated under net house conditions. The tomato crop was positively influenced by inoculation of MT7 over the un-inoculated plants. Therefore, it is concluded that competent colonization by MT7 lies in its ability to respond to tomato root exudates, form biofilms, establish and proliferate in the tomato rhizosphere and express various PGP traits that cause an increase in plant growth. The results indicate the potential of MT7 as a bio-inoculant for tomato.

Mobile communication devices (MCDs), including cell phones and smart phones, have become an essential part of everyday life. Despite their frequent usage, most people, even healthcare personnel, often ignore the possibility that these devices might accumulate to carry a variety of microbial flora during and after the inspection of patients. The handling of MCDs with unwashed hands and/or their seldom cleaning can aggravate potential health risks. Many of the harbored bacteria species can be harmful to immune-suppressed patients for whom the disinfection precautions should be taken more seriously. In this review, we discuss the significance of maintaining the cleanliness of mobile devices, especially in healthcare settings, to prevent the spread of nosocomial infections in patients. Furthermore, we discuss strategies to address microbial contamination of MCDs to maintain good hand hygiene for the users of smartphones or other mobile communication devices. These techniques are capable of providing instant disinfection of the devices along with residual effects over prolonged periods.

Sustainable biorefinery systems procured from lignocellulosic biomass depicts the future of bio-energy, with low cost, availability and wide spread dispersal of biomass resources it aids towards goal of “Waste to Use”. Evidentially research has focused mainly on use of bio-fuel and merits of varied potent pretreatment approaches that have been implemented. The use of chemical and physicochemical pretreatments procured maximum yield for fermentable sugars. This review compiles several lignin derived thermoset and thermoplastic polymers and copolymers like polyesters, epoxy resins that act as great substitute for petroleum attained polymer. Evidential research has favored use of vanillin to produce aldehyde or phenol derived commercialized products. Epoxy resins have been successfully proven to produce thermally stable, mechanically strong and flexible thermosets with strong binding ability. Lignin based polyesters and polyanhydrides have proven to depict good antioxidant property. Biochar production assisted its usage to remove harmful chemicals from waste water shed systems and its usage as fertilizer. Depolymerization of woody biomass show pressure sensitive adhesive characteristic when applied on fine stainless steel. The review presents latest findings discussing the production of various applicative products from lignocellulosic biomass that can act as key platform for small scale industries development. In the era of nanotechnology, cellulosic nanofibrils tended to have flexibility and shear holding activity. Genetically engineered methods like over expression of enzymes triggered the production of xylitol and its usage as artificial sweetner. Thus, ruins of lignocellulosic scrap can serve as profitable small scale industrial set ups to provide above mentioned industrial products.

The environment is under constant threat due to the huge accumulation of the keratinaceous wastes produced by poultry processing industries and poultry farms. Millions of tons of feather wastes are produced each year as a by-product that causes severe environmental pollution. Their degradation is tough due to the presence of insoluble, highly stiff, recalcitrant ‘keratin’ polypeptide. Keratin are resistant to degradation by common proteases and chemical catalysts due to high mechanical stability and cross-linked disulphide bonds present in their structure. Microbial keratinases has emerged as a powerful bio-catalyst that can potentially degrade keratin and transform the keratinaceous wastes into value-added products. Keratinase production is receiving worldwide attention for its application in sustainable development and cleaner production. The enzymatic hydrolysis of keratin have the potential for higher productivity, less energy consumption, less effluent generation and waste management. Keratinases add value to poultry and industrial wastes which brings economic feasibility and environmental sustainability. The present review prioritized the various aspects of keratinolytic proteases in bringing sustainable development to the economy of a nation. It also focuses on the recent advancement in the production of microbial keratinases with emphasis on the biochemical characteristics related to enzyme activity and stability, development of novel recombinant and mutant microbial strains along with different optimization strategies leading to expansive production and yield of keratinases. Furthermore, different properties of microbial keratinases which renders them as a green and sustainable material for industrial applications in waste management, textile, leather and detergents with advantages over conventional treatments have also been discussed.

This study aimed for the partial purification, biochemical characterization, determination of bioprocess and thermodynamic parameters of mannanase from newly isolated strain Enterobacter asburiae SD26 under submerged culture. From different variables, locust bean gum and combination of peptone + yeast extract was found as best carbon and nitrogen sources respectively. The profiles of mannanases production and growth kinetics of E. asburiae SD26 were similar. The maximum specific growth rate (μmax) and productivity ( γ Pmax) of enzyme was 0.02 h-1 and 0.006 g l -1hr-1. The highest mannanases activity was achieved at pH 6.0 and temperature 50°C. The kinetic parameters of mannanases was Km = 25 mg.ml-1, Vmax= 2500 μmol.min-1.ml-1 and thermodynamic parameters of enzyme, Δ H d ° , Δ G d ° , Δ S d ° were 67.74 KJmol-1, 105.19 KJmol-1, − 115.89 J.mol-1.K-1 respectively, recorded for mathematical description of the mannanase action at different process conditions.

Laccase synthesizing Acinetobacter sp. UIETPU was isolated from the rhizosphere of the paddy plant. Enzyme was firmly cell attached and no extracellular laccase activity was detected up to 96h, 37○C, and 150 rpm. Nanoparticles (NPs) of Cu and CuO (100 μM) increased the cell-bonded laccase synthesis by 2.1 and 2.3 fold respectively, but potent laccase inducer CuSO4 enhanced the enzyme production by 1.5 fold at the same concentration. There was no adverse effect of NaCl (0.5–5.0%) on laccase synthesis when added to the production media. Enzyme oxidizes the syringaldazine and 2, 6-dimethoxyphenol (specific substrates of laccase) and inhibited by the dithiothreitol (DTT), sodium azide and cystein by 98, 65 and 52% respectively. Cell-bonded laccase showed the 100% activity up to 2h and t 1 2 of the bonded enzyme was 4h at 80○C. Field emission scanning electron microscopy (FESEM) revealed that there was no lysis of Acinetobacter sp. UIETPU cells in the presence of CuO NPs.

Pesticides are being used extensively all over the world to increase agricultural output. However, their use may have radical effects on humans and the environment. Thus, there is a dire need to develop new technologies so as to restrict the use of pesticides/agrochemicals to lower concentrations. In this regard, nanotechnology may provide promising solutions to the problems in the field of agriculture and food science. In the present study, we have synthesized chitosan and agrochemical loaded (spinosad and permethrin) chitosan nanoparticles and characterized them using XRD, FT-IR, UV–Vis, DLS/Zeta potential, FE-SEM, and HR-TEM. Chitosan is a skilled and resourceful polymer that has been used in the field of agriculture as nanoparticles. Chitosan nanoparticles are biodegradable in nature, non-toxic carriers for nucleotides and drugs, biocompatibility and have excellent adsorption abilities. After synthesis, the toxicity of chitosan and agrochemical loaded chitosan nanoparticles was checked on Drosophila melanogaster (model organism) at several concentrations (10, 50, 100 μg/mL) of nanoparticles. Assays such as survivability assay, climbing assay, and the larval crawling assay were performed to monitor and observe the toxicity of chitosan and agrochemical loaded chitosan nanoparticles and the results were compared with free agrochemicals. Results showed the agrochemical loaded chitosan nanoformulations to be more effective with a lasting residual effect as compared to the free agrochemicals. Thus, in conclusion, these nanoformulations may be used for insect pest management.