S-triazines are a group of herbicides that are extensively applied to control broadleaf weeds and grasses in agricultural production. They are mainly taken up through plant roots and are transformed by xylem tissues throughout the plant system. They are highly persistent and have a long half-life in the environment. Due to imprudent use, their toxic residues have enormously increased in the last few years and are frequently detected in food commodities, which causes chronic diseases in humans and mammals. However, for the safety of the environment and the diversity of living organisms, the removal of s-triazine herbicides has received widespread attention. In this review, the degradation of s-triazine herbicides and their intermediates by indigenous microbial species, genes, enzymes, plants, and nanoparticles are systematically investigated. The hydrolytic degradation of substituents on the s-triazine ring is catalyzed by enzymes from the amidohydrolase superfamily and yields cyanuric acid as an intermediate. Cyanuric acid is further metabolized into ammonia and carbon dioxide. Microbial-free cells efficiently degrade s-triazine herbicides in laboratory as well as field trials. Additionally, the combinatorial approach of nanomaterials with indigenous microbes has vast potential and considered sustainable for removing toxic residues in the agroecosystem. Due to their smaller size and unique properties, they are equally distributed in sediments, soil, water bodies, and even small crevices. Finally, this paper highlights the implementation of bioinformatics and molecular tools, which provide a myriad of new methods to monitor the biodegradation of s-triazine herbicides and help to identify the diverse number of microbial communities that actively participate in the biodegradation process.
The fundamental existence of any living organism necessitates the availability of pure and safe water. The ever-increasing population has led to extensive industrialization and urbanization, which have subsequently escalated micropollutants and water contamination. The environmental impact on various life forms poses a dire need for research in effective environmental management. Versatile technologies involving multiple approaches, including physiochemical and biological bioremediation strategies, draw insights from environmental biology. Metabolic annihilation mediated by microbes shows significant potential in the bioconversion of toxic micropollutants to tolerable limits. Environmentally friendly, cost-effective, and sustainable strategies are envisaged for efficient environmental protection. Phytoremediation technology, especially floating wetland treatments, facilitates micropollutant elimination, landscape management, ecosystem conservation, and aesthetic enhancement in diverse environments. The incorporation of nanomaterials in the bioremediation of toxic micropollutants augments novel and innovative strategies for water pollution abatement. This paper offers a novel strategy that combines nanomaterials to improve micropollutant degradation with bioremediation techniques, particularly the creative application of phytoremediation technologies like floating wetlands. Combining these techniques offers a novel viewpoint on long-term, affordable approaches to reducing water pollution. Additionally, the review proposes a forward-looking strategic framework that addresses the accumulation and refractory nature of micropollutants, which has not been thoroughly explored in previous literature.
Agro-industrial by-products from beetroot, raspberry, sea buckthorn, and shadbush are valuable sources of natural pigments and renewable filler materials, but their hydrophilic surfaces limit compatibility with hydrophobic polydimethylsiloxane (PDMS) matrices. This study evaluated the effect of catalyst-free vapor-phase hexamethyldisilazane (HMDS) treatment of pigment-rich powders and their incorporation into PDMS composites at 5 and 20 wt.% filler loadings. Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy, and contact angle measurements were used to characterize surface modifications. Mechanical behavior under puncture loading was evaluated using texture analysis. FTIR confirmed successful silylation through the reduction in hydroxyl groups and the emergence of silicon-containing functionalities. Treated fillers exhibited rougher, more irregular surfaces, which suggested improved filler dispersion and interfacial compatibility within the PDMS matrix. Modified composites showed enhanced hydrophobicity, with contact angles up to 102.84°. Composites containing 5 wt.% HMDS-treated raspberry filler demonstrated the highest puncture resistance and elasticity, indicating improved interfacial interactions. In contrast, 20 wt.% filler loading generally reduced puncture resistance and elasticity, possibly due to increased particle agglomeration and reduced matrix continuity, as suggested by the SEM observations, whereas shadbush-filled composites showed decreased performance after treatment. Overall, HMDS surface modification effectively improves the compatibility of pigment-rich agro-waste fillers with PDMS and supports their use as functional fillers and natural colorant sources in silicone-based composites, providing a value-added route for the utilization of agro-industrial by-products.