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Dyes are one of the most hazardous chemicals causing significant environmental pollution and affecting water quality. Majority of the existing methods for dye removal and degradation involve synthetic membranes and use of hazardous chemicals, further resulting in secondary pollution. The present study reports polysaccharide based novel composite hydrogel as biodegradable matrix for pH-responsive selective adsorption of cationic/anionic dyes. This membrane showed pH-responsive adsorption of methyl green (MG) and methyl orange (MO) with similar adsorption equilibrium, i.e., 315 and 276 mg g−1, respectively. Interestingly, selective adsorption at different pH has allowed separation of dye mixtures that holds incredible industrial importance for dyes recovery. The hydrogel matrix was able to completely separate MG, a model cationic dye at neutral pH from the dye mixture whereas, it was possible to remove 60% MO, a model anionic dye at acidic pH. Furthermore, comprehensive isothermal and kinetic studies of adsorption revealed that Freundlich isotherm describing the multilayer coverage and pseudo-second-order kinetics were followed. Thermodynamic studies indicated that the adsorption process was spontaneous and endothermic. In fact, the membrane was reusable for at least ten cycles and exhibited desorption efficiency of 80 and 60% for MO and MG, respectively, which may be further recycled to make the process environmentally sustainable. Overall, this study proposes an inexpensive, simple, biologically safe, and efficient adsorbent material for dye effluent treatment.

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Hydrogels are a soft material that undergoes cross-linking between polymers to form a hydrophilic three-dimensional network. In fact, similarity to body tissue, soft consistency, biocompatibility, and elasticity, impart a protagonic role of hydrogel to be applied as a biomaterial. In response to external cues, stimuli-responsive hydrogels are particularly impactful, enabling remarkable levels of control over material properties. They can endure changes in swelling behavior, permeability, network structure, and mechanical strength. Nevertheless, such changes induce single-cycle or reversible transitions, so hydrogels can regain their initial state once the trigger is removed. Recently, polysaccharide-based hydrogels with stimuli-responsive properties resulted in developing biomimetic structures for a widespread biotechnological application owing to their excellent biodegradability, biocompatibility, nonimmunogenicity, functional properties, ease of gelation, and derivatization. This review will initially highlight recent advances in cross-linking methods and chemistry for preparing stimuli-responsive hydrogels. Subsequently, state-of-the-art techniques to understand the structural, chemical, and rheological behavior of polysaccharide-based stimuli-responsive hydrogel will be discussed. Additionally, the responsiveness of polysaccharide hydrogel toward diverse stimuli such as redox, temperature, light, pH, magnetism, electricity, etc., with a broad spectrum of applications will be described in detail. This review also attempts to address the lacunae of existing stimuli-responsive hydrogel and their future perspectives.

In recent times, nutrition and diet have become prominent health paradigms due to sedentary lifestyle disorders. Preventive health care strategies are becoming increasingly popular instead of treating and managing diseases. A nutraceutical is an innovative concept that offers additional health benefits beyond its fundamental nutritional value. These nutraceuticals have the potential to reduce the exorbitant use of synthetic drugs because the modern medicine approach of treating diseases with high-tech, expensive supplements, and long-term consequences aggravates consumers. However, most nutraceuticals are plant-derived, making them susceptible to degradation and prone to chemical instability, poor solubility, unpleasant taste, and bioactivity loss before absorption to the targeted site. To counteract this problem, the bioavailability of these labile compounds can be maximized by encapsulating them in protective nanocarriers. It is crucial that nanoencapsulation technologies convert bioactive compounds into forms that can be easily combined with functional foods and beverages without adversely affecting their organoleptic properties. In recent years, nanoformulations using food-grade materials, such as polysaccharides, proteins, lipids, etc., have received considerable attention. Among them, microbial polysaccharides are biocompatible, nontoxic, and nonimmunogenic, and most of them are US-FDA approved and can undergo tailored modifications. The nanoformulation of microbial polysaccharide is a relatively new frontier which has several advantages over existing systems. The present article, for the first time, comprehensively reviews microbial polysaccharides-based nanodelivery systems for nutraceuticals and discusses various techno-commercial aspects of these nanotechnological preparations. Moreover, this has also attempted to draw a future research perspective in this area.

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The food systems approach can contribute to food security and reduced malnutrition levels by identifying key investments and policies throughout the food system, including production, processing, marketing, and consumption of food. However, in countries facing fragility and conflict, it has proven difficult to implement such an approach and achieve the desired results. This has been the case in Afghanistan, where high levels of malnutrition stem in part from an undersupply of nutritious food. Multi-sectoral approaches to promote nutrition sensitivity and achieve diet-based solutions have also had only limited impact. This paper reports on an analysis of the nutrition sensitivity of food systems in Afghanistan using multi-sector consultations and gap analyses to examine two key food and nutrition policies, the National Comprehensive Agriculture Development Priority Program and the Afghanistan Food Security and Nutrition Agenda. It highlights gaps in the policies and identifies investment priorities to make food systems more nutrition sensitive. The results show that instilling nutrition sensitivity into the operation of Afghanistan's food systems can only be accomplished if certain key measures are incorporated into the food system. These include addressing the absence of knowledge in the population regarding healthy diets, the lack of sufficient food for vulnerable populations, weak irrigation systems, capacity constraints at individual and institutional levels, data challenges, and weak natural resource management. In addition, the above weaknesses are compounded by the continued violence and conflict-induced insecurity, weak government, and inadequate investments. Given the role of different sectors in contributing to improved nutrition, appropriate and effective multistakeholder coordination and collaboration is paramount to such efforts.