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This study presents, the synthesis of microwave‐assisted biodegradable polyacrylamide grafted tragacanth gum (Tr‐g‐PAM), which was utilized as a bioflocculant to treat textile effluent and compared against the conventional flocculant. The reaction parameters for maximal grafting were optimized by varying the reaction factors. The grafting of acrylamide onto the backbone of Tragacanth gum was confirmed by FTIR, XRD, TGA, and SEM–EDX studies. Swelling studies were performed in deionized water and different salts. Tr‐g‐PAM exhibited pH and temperature‐dependent swelling behavior. Biodegradation studies of the graft copolymer were carried out by the soil composting method. Tr‐g‐PAM showed 91.54% degradation within 60 days, compared to Tragacanth, which degraded within 15 days. SEM techniques were used to describe various phases of biodegradation. Flocculation performances of the graft copolymers were evaluated in simulated colloidal wastewater. Influencing variables such as bioflocculant dosage, pH, and flocculation mixing speed were examined. The maximum decolorization at the optimum pH of 6 and 120 mg/L dosage was found to be 91.8% and 88.5% for Tr‐g‐PAM and Tragacanth. In conclusion, a biodegradable Tr‐g‐PAM with better flocculation efficiency than that of Tragacanth and other commercial flocculants would be a promising choice as an eco‐friendly adsorbent for the removal of contaminants from water resources. [ABSTRACT FROM AUTHOR]

The toxic effect of TiO2 nanoparticles (TNP) greatly varies with the variation in synthesis protocol followed. Any morphological alteration of TNPs affects their activity. In the present study, we report the detailed toxicological analysis of TNPs fabricated by a microwave irradiation–assisted hybrid chemical approach. The toxicological mechanism was studied in human colon cancer cell lines (HCT116). Results indicate that TNP induces oxidative stress on HCT116, which, in turn, causes mitochondrial membrane depolarization. We also observed activation of Bcl-2 and caspase-3 by Western blot analysis. This indicates TNPs induce mitochondrial-mediated apoptosis. Furthermore, G1 cell cycle arrest was observed by flow-cytometric analysis. This study provides an understanding of the mechanism of action for apoptosis induced by TNPs, which can be further used to design safe TNPs for various consumer products and also suggests that extensive research needs to be done on harmful effects of TNPs synthesized from different approaches before commercial application.

Cling films and single‐use plastics are difficult to recycle and cause major environmental pollution, leading to an increase in microplastics in nature. To overcome this issue, biodegradable films are being explored more extensively. Seaweed is gaining prominence in the food packaging sector since it is beneficial in all aspects. Two fractions of Indian brown seaweed Sargassum wightii, biopolymer (sulfated polysaccharide [SP]) as base material and nanofillers (cellulose nanocrystals [CNC]) as reinforced filler are employed to develop a sustainable cling film for food packaging. This cellulose filler can be isolated from solid seaweed biomass after the polysaccharide extraction and converted into nanoform using the response surfaces method (RSM) to maximize the yield of CNC. The objective of this research is to construct seaweed‐based biodegradable nanocomposite films and to examine their improved properties. It exhibited a gradual decrease in water absorption and water vapor permeability (WVP), along with better wettability, mechanical, and antioxidant properties, and thermal analysis compared with the control SP film. The degradation rates of the films were analyzed using the soil‐burial method. According to the results obtained, it is suggested that CNC can be utilized as a functional filler to improve the qualities of seaweed‐based cling films. [ABSTRACT FROM AUTHOR]