Enzyme-based solutions for textile processing and dye contaminant biodegradation—a review

The textile industry, as recognized conformist and stake industry in the world’s economy, is facing serious environmental challenges. In numerous industries, in practice, various chemical-based processes from initial sizing to final washing are fascinating harsh environment concerns. Some of these chemicals are corrosive to equipment and cause serious damage itself. Therefore, in the twenty-first century, chemical and allied industries quest a paradigm transition from traditional chemical-based concepts to a greener, sustainable, and environmentally friendlier catalytic alternative, both at the laboratory and industrial scales. Bio-based catalysis offers numerous benefits in the context of biotechnological industry and environmental applications. In recent years, bio-based processing has received particular interest among the scientist for inter- and multi-disciplinary investigations in the areas of natural and engineering sciences for the application in biotechnology sector at large and textile industries in particular. Different enzymatic processes such as chemical substitution have been developed or in the process of development for various textile wet processes. In this context, the present review article summarizes current developments and highlights those areas where environment-friendly enzymatic textile processing might play an increasingly important role in the textile industry. In the first part of the review, a special focus has been given to a comparative discussion of the chemical-based “classical/conventional” treatments and the modern enzyme-based treatment processes. Some relevant information is also reported to identify the major research gaps to be worked out in future.     

Impacts of changing climate and snow cover on the flow regime of Jhelum River,Western Himalayas

Regional Environmental Change - This study examines the change in climate variables and snow cover dynamics and their impact on the hydrological regime of the Jhelum River basin in Western...     

From socioeconomic disparity to environmental injustice: the relationship between housing unit density and community green space in a medium city in Pakistan

Rapid urbanisation, lack of proactive planning and improper allocation of resources may result in socio-economic disparity among and within cities, causing social unrest and environmental injustice in the neighbourhoods. This study aims to examine whether the planning standards for housing schemes in Pakistan are able to maintain equitable access to green spaces within the cities. Ten residential sites in Sheikhupura city with different housing unit sizes and densities were selected for the study. The supply of urban green infrastructure in housing scheme has been assessed: (i) by comparing the percentage of green spaces, including community parks and open spaces and street landscape; and (ii) by calculating per dwelling unit and per capita share of green spaces. These indicators have been studied against the housing density and population density of the schemes by applying correlation and linear regression models. The results show that all the housing schemes plans provide for similar amounts of green space as a percentage of total area. The per capita share of green spaces is very low in high-density areas, but interestingly, the street landscape has a higher potential to contribute to the overall landscape in high-density neighbourhoods, compensating for low per capita green space. Housing unit density and population density must be incorporated in planning standards so planners can effectively devise a mix of community parks, street landscape and private green spaces to help maintain per capita green spaces, and hence environmental resource equality in different parts of the city.     

Long-term (≥20 years) application of fertilizers and straw return enhances soil carbon storage: a meta-analysis

Increasing soil carbon (C) storage is crucial to addressing climate change and ensuring food security. The C sequestration potential of the world’s cropland soil is 0.4–0.8 Pg soil C year^?1, which may be achieved through the adoption of recommended management practices (RMPs), including fertilizer management. This study aimed to quantitatively evaluate the influence of long-term application of different fertilizers and straw retention on soil organic carbon (SOC) storage, to compare the calculated response ratios with Intergovernmental Panel on Climate Change (IPCC)-recommended default relative stock change factors, and to propose recommendations for enhancing SOC sequestration. The meta-analysis indicated that the long-term application of chemical fertilizers (CF), organic fertilizers (OF), combined chemical and organic fertilizers (CFOF), and straw return (SR) significantly enhanced the SOC storage. Response ratios varied significantly (p < 0.05) across different fertilization measures and climatic zones, and was sensitive to the initial SOC content. The mean response ratio was 0.94 for no fertilizer (NF), 1.08 for CF, 1.48 for OF, 1.38 for CFOF, and 1.28 for SR. When IPCC default values for response ratios were applied, SOC storage with OF and CFOF treatments in warm temperate regions with a dry climate was underestimated by 26%, and in the cool temperate region with a moist climate was overestimated by 25% (p < 0.05). Analysis showed that sustained application of organic fertilizers and straw return could be a beneficial measures to mitigate climate change and ensure food security in China. Our findings highlight the importance of deriving SOC stock change factors for a detailed classification of cropland by fertilizer management, climate, and soil types in order to more accurately reflect the effects of policy measures.     

Visible-light-driven photocatalytic dual-layer hollow fibre membrane ameliorates the changes of bisphenol A exposure in gastrointestinal tract

Environmental Science and Pollution Research - Various treatments of choice are available to overcome contamination of bisphenol A (BPA) in the environment including membrane technologies; however,...     

Preparation and characterization of glass hollow fiber membrane for water purification applications

This work discusses the preparation and characterizations of glass hollow fiber membranes prepared using zeolite-5A as a starting material. Zeolite was formed into a hollow fiber configuration using the phase inversion technique. It was later sintered at high temperatures to burn off organic materials and change the zeolite into glass membrane. A preliminary study, that used thermogravimetric analysis (TGA), X-ray diffraction (XRD), and Fourier transform infrared (FTIR), confirmed that zeolite used in this study changed to glass at temperatures above 1000 °C. The glass hollow fiber membranes prepared using the phase inversion technique has three different microstructures, namely (i) sandwich-like structure that originates from inner layer, (ii) sandwich-like that originates from outer layer, and (iii) symmetric sponge like. These variations were influenced by zeolite weight loading and the flow rate of water used to form the lumen. The separation performances of the glass hollow fiber membrane were studied using the pure water permeability and the rejection test of bovine serum albumin (BSA). The glass hollow fiber membrane prepared from using 48 wt% zeolite loading and bore fluid with 9 mL min^?1 flow rate has the highest BSA rejection of 85% with the water permeability of 0.7 L m^?2 h^?1 bar^?1. The results showed that the separation performance of glass hollow fiber membranes was in the ultrafiltration range, enabled the retention of solutes with molecular sizes larger than 67 kDa such as milk proteins, endotoxin pyrogen, virus, and colloidal silica.     

Biology and management of two important <Emphasis Type="Italic">Conyza</Emphasis> weeds: a global review

Weed management is one of the prime concerns for sustainable crop production. Conyza bonariensis and Conyza canadensis are two of the most problematic, noxious, invasive and widespread weeds in modern-day agriculture. The biology, ecology and interference of C. bonariensis and C. canadensis have been reviewed here to highlight pragmatic management options. Both these species share a unique set of biological features, which enables them to invade and adapt a wide range of environmental conditions. Distinct reproductive biology and an efficient seed dispersal mechanism help these species to spread rapidly. Ability to interfere strongly and to host crop pests makes these two species worst weeds of cropping systems. These weed species cause 28–68 % yield loss in important field crops such as soybean and cotton every year. These weeds are more prevalent in no-till systems and, thus, becoming a major issue in conservation agriculture. Cultural practices such as crop rotations, seed rate manipulation, mulching, inter-row tillage and narrow row spacing may provide an effective control of these species. However, such methods are not feasible and applicable under all types of conditions. Different herbicides also provide a varying degree of control depending on crop, agronomic practices, herbicide dose, application time and season. However, both these species have evolved resistance against multiple herbicides, including glyphosate and paraquat. The use of alternative herbicides and integrated management strategies may provide better control of herbicide-resistant C. bonariensis and C. canadensis. Management plans based on the eco-biological interactions of these species may prove sustainable in the future.     

Using GIS tools to detect the land use/land cover changes during forty years in Lodhran District of Pakistan

Environmental Science and Pollution Research - Land use/land cover (LULC) change has serious implications for environment as LULC is directly related to land degradation over a period of time and...     

Recent progress in bioethanol production from lignocellulosic materials: A review

Natural energy sources like petrol and diesel are going to be diminished in the coming future which will lead to increase in the prices and demands of fossil fuels. Therefore, it is important to find a sustainable alternate of fossil fuels. Bioethanol is one of the alternatives, which is produced from different feedstocks including sugar-based, starch-based and lignocellulose-based materials through fermentation. Since sugar-based (sugar cane and sugar beet) and starch-based (corn) materials are sources of staple food, therefore, research on lignocellulosic materials for bioethanol production is a subject of recent studies. Ethanol production from lignocellulosic materials involves different steps, such as pretreatment, hydrolysis, followed by fermentation process and finally ethanol purification. In this review, we have summarized the recent progresses in bioethanol production and processing from lignocellulosic materials.     

Visible light photocatalytic water disinfection and its kinetics using Ag-doped titania nanoparticles

The UN estimated about five million deaths every year due to water-borne diseases, accounting from four billion patients. Keeping in view, the ever increasing health issues and to undermine this statistics, a reliable and sustainable water-treatment method has been developed using visible light for water treatment. titania nanoparticles (NPs) have been synthesized successfully by a more applicable method Viz: liquid impregnation (LI) method. The bacterial death rate by photocatalysis under visible light was studied by employing a typical fluorescent source and was found to follow pseudo first-order reaction kinetics. The nanoparticles were characterized using X-ray diffraction (XRD), scanning electron microscopy, and energy-dispersive X-ray spectroscopy to deduce their size range, surface morphology, and elemental compositions, respectively. Among all the prepared grades, 1 % Ag–TiO₂ was found to be a very effective photocatalytic agent against Escherichia coli. The resulted photoinactivated data were also evaluated by different empirical kinetic models for bacterial inactivation. Hom, Hom-power, Rational, and Selleck models were not able to explain the disinfection kinetics but modified-Hom model fitted best with the experimentally obtained data by producing a shoulder, log-linear, and a tail region.