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The composition and the organization of soil are changing rapidly by the diverged mankind activities, leading to the contamination of environment. Several methods are employed to clean up the environment from these kinds of contaminants, but most of them are costly and ineffective to yield optimum results. Phytoremediation is a natural green technology, which is eco-friendly for the removal of toxic metals from the polluted environment. Phytoremediation is a cost-effective technique through which the cleanup of contaminated soil laced with heavy metals is performed by wild weeds and small herbal plants. The phytoremediation technique provides a promising tool for hyperaccumulation of heavy metals; arsenic, lead, mercury, copper, chromium, and nickel, etc., by the wild weeds and that has been discussed here in detail in case of Cannabissativa, Solanum nigrum and Rorippa globosa. In general, weeds that have the intrinsic capacity to accumulate metals into their shoots and roots, have the ability to form phytochelates and formation of stable compound with ions. This behavior of accumulation along with chelate and stable compound formation is utilized as a tool for phytoremediation activity.

Bone-related diseases have been increasing worldwide, and several nanocomposites have been used to treat them. Among several nanocomposites, polyhydroxybutyrate (PHB)-based nanocomposites are widely used in drug delivery and tissue engineering due to their excellent biocompatibility and biodegradability. However, PHB use in bone tissue engineering is limited due to its inadequate physicochemical and mechanical properties. In the present work, we synthesized PHB-based nanocomposites using a nanoblend and nano-clay with modified montmorillonite (MMT) as a filler. MMT was modified using trimethyl stearyl ammonium (TMSA). Nanoblend and nano-clay were fabricated using the solvent-casting technique. Inspection of the composite structure revealed that the basal spacing of the polymeric matrix material was significantly altered depending on the loading percentage of organically modified montmorillonite (OMMT) nano-clay. The PHB/OMMT nanocomposite displayed enhanced thermal stability and upper working temperature upon heating as compared to the pristine polymer. The dispersed (OMMT) nano-clay assisted in the formation of pores on the surface of the polymer. The pore size was proportional to the weight percentage of OMMT. Further morphological analysis of these blends was carried out through FESEM. The obtained nanocomposites exhibited augmented properties over neat PHB and could have an abundance of applications in the industry and medicinal sectors. In particular, improved porosity, non-immunogenic nature, and strong biocompatibility suggest their effective application in bone tissue engineering. Thus, PHB/OMMT nanocomposites are a promising candidate for 3D organ printing, lab-on-a-chip scaffold engineering, and bone tissue engineering.

Bioethanol is recognized as a valuable substitute for renewable energy sources to meet the fuel and energy demand of the nation, considered an environmentally friendly resource obtained from agricultural residues such as sugarcane bagasse, rice straw, husk, wheat straw and corn stover. The energy demand is sustained using lignocellulosic biomass to produce bioethanol. Lignocellulosic biomass (LCBs) is the point of attention in replacing the dependence on fossil fuels. The recalcitrant structure of the lignocellulosic biomass is disrupted using effective pretreatment techniques that separate complex interlinked structures among cellulose, hemicellulose, and lignin. Pretreatment of biomass involves various physical, chemical, biological, and physiochemical protocols which are of importance, dependent upon their individual or combined dissolution effect. Physical pretreatment involves a reduction in the size of the biomass using mechanical, extrusion, irradiation, and sonification methods while chemical pretreatment involves the breaking of various bonds present in the LCB structure. This can be obtained by using an acidic, alkaline, ionic liquid, and organosolvent methods. Biological pretreatment is considered an environment-friendly and safe process involving various bacterial and fungal microorganisms. Distinct pretreatment methods, when combined and utilized in synchronization lead to more effective disruption of LCB, making biomass more accessible for further processing. These could be utilized in terms of their effectiveness for a particular type of cellulosic fiber and are namely steam explosion, liquid hot water, ammonia fibre explosion, CO2 explosion, and wet air oxidation methods. The present review encircles various distinct and integrated pretreatment processes developed till now and their advancement according to the current trend and future aspects to make lignocellulosic biomass available for further hydrolysis and fermentation.

Uncontrolled waste generation and management difficulties are causing chaos in the ecosystem. Although it is vital to ease environmental pressures, right now there is no such practical strategy available for the treatment or utilisation of waste material. Because the Earth's resources are limited, a long‐term, sustainable, and sensible solution is necessary. Currently waste material has drawn a lot of attention as a renewable resource. Utilisation of residual biomass leftovers appears as a green and sustainable approach to lessen the waste burden on Earth while meeting the demand for bio‐based goods. Several biopolymers are available from renewable waste sources that have the potential to be used in a variety of industries for a wide range of applications. Natural and synthetic biopolymers have significant advantages over petroleum‐based polymers in terms of cost‐effectiveness, environmental friendliness, and user‐friendliness. Using waste as a raw material through industrial symbiosis should be taken into account as one of the strategies to achieve more economic and environmental value through inter‐firm collaboration on the path to a near‐zero waste society. This review extensively explores the different biopolymers which can be extracted from several waste material sources and that further have potential applications in food packaging industries to enhance the shelf life of perishables. This review‐based study also provides key insights into the different strategies and techniques that have been developed recently to extract biopolymers from different waste byproducts and their feasibility in practical applications for the food packaging business.