Biosynthesis and Mathematical Interpretation of Zero-Valent Iron NPs Using Nigella sativa Seed Tincture for Indemnification of Carcinogenic Metals Present in Industrial Effluents

Green low-cost synthesis of zero-valent iron nanoparticles from Palm Petiole Extract for Cr(VI) removal from water

One of the hottest research topics over the last decades was the valorization or/and recycling of agro-industrial wastes into different valuable liquid or solid products, which is considered a sustainable and low-cost approach. In this study, we developed zero-valent iron nanoparticles from Palm Petiole Extract (P-NZVI) using a green and straightforward approach. The as-synthesized P-NZVI was used to adsorb Cr(VI) in water. The physico-chemical characterizations of P-NZVI, including the particle size, crystalline structure, surface area, morphology, and functional groups, were investigated via several techniques such as UV-vis spectroscopy, SEM, TEM, XRD, FTIR, AFM, DLS, pHZPC measurement, and BET analysis. The adsorption performance of P-NZVI was studied under different operational parameters, including pollutant concentration, pH, temperature, and adsorbent mass. The adsorption rate was found to be 89.3% within 40 min, corresponding to the adsorption capacity of 44.47 mg/g under the following conditions: initial Cr(VI) concentration of 40 mg/L, pH 5, and a P-NZVI dosage of 1 g/L. It was found that the adsorption pattern follows the Langmuir and the pseudo-second-order kinetic models, indicating a combination of monolayer adsorption and chemisorption mechanisms. The thermodynamic study shows that the adsorption process is endothermic and spontaneous. The reusability of P-NZVI was carried out four times, showing a slight decrease from 89.3 to 87%. These findings highlight that P-NZVI's could be an effective green adsorbent for removing Cr(VI) or other types of toxic pollutants from water.

Evaluating the MDCK cell permeability of greenly synthesize bimetallic Ag/Zn Nanoparticles using leaf extract of Vallaris solanacea as a potential antipesticide-resistant agent

Bimetallic nanoparticles, particularly Ag/Zn bimetallic nanoparticles, have gained increasing attention due to their unique properties, making them suitable for a variety of applications such as catalysis, water treatment, and environmental remediation. This study aimed to elucidate the use of bimetallic nanoparticles of Ag/Zn as an alternative to resistant pesticides for pest control. Furthermore, this research demonstrates that BNPs can target specific pollutants and degrade them through various mechanisms. BNP docking with the Nilaparvata lugens cytochrome P450 (CYP6ER1) protein exhibited the lowest binding energy of -7.5 kcal/mol. The cell permeability analysis of BNP in plant cells reveals that the BNP has 0 % permeability towards any cell at -10 kcal/mol energy, which is the lowest free energy translocation pathway. The harmful leftover residues of the pesticides have a higher chance of degradability in case of interaction with BNP validated by chemical-chemical interaction analysis. Additionally, MDCK permeability coefficient of small molecules based on the regression model was calculated for BNP which authenticated the efficiency of BNP. Moreover, Swiss ADMET simulated absorption using a boiled egg model with no blood-brain barrier and gastrointestinal crossing for the expected BNP molecule has been observed. Significantly, the findings indicate that employing bimetallic nanoparticles like Ag/Zn is a crucial strategy for bioremediation because they proficiently decompose pesticides while posing no risk to humans. Our results will facilitate the design of novel BNPs materials for environmental remediation and pest control ensuring human health safety that are predicated on bimetallic nanoparticles.

Green Synthesis of Silver Nanoparticles Using the Cell-Free Supernatant of Haematococcus pluvialis Culture

The green synthesis of silver nanoparticles (AgNPs) using the cell-free supernatant of a Haematococcus pluvialis culture (CFS) was implemented in the current study, under illumination conditions. The reduction of Ag+ to AgNPs by the CFS could be described by a pseudo-first-order kinetic equation at the temperature range tested. A high reaction rate during synthesis and stable AgNPs were obtained at 45 °C, while an alkaline pH (pH = 11.0) and a AgNO3 aqueous solution to CFS ratio of 90:10 (v/v) proved to be the most effective conditions in AgNPs synthesis. A metal precursor (AgNO3) at the concentration range tested (1-5 mM) was the limited reactant in the synthesis process. The synthesis of AgNPs was accomplished under static and agitated conditions. Continuous stirring enhanced the rate of reaction but induced aggregation at prolonged incubation times. Zeta potential and polydispersity index measurements indicated stable AgNPs and the majority of AgNPs formation occurred in the monodisperse phase. The X-ray diffraction (XRD) pattern revealed the face-centered cubic structure of the formed AgNPs, while TEM analysis revealed that the AgNPs were of a quasi-spherical shape with a size from 30 to 50 nm. The long-term stability of the AgNPs could be achieved in darkness and at 4 °C. In addition, the synthesized nanoparticles showed antibacterial activity against Escherichia coli.

Elucidating the effects of heavy metals contamination on vital organ of fish and migratory birds found at fresh water ecosystem

Heavy metal pollution in aquatic environments threatens marine life and lowers the quality of freshwater supplies. This research aimed to quantify the heavy metal concentration in fish, avian tissue, and water of the Mangla reservoir. Concentrations of heavy metals such as Cu, Cd, Cr, and Pb were determined in five vital organs of six species of fishes (Cirrhinus cirrhosis, Catla catla, Hypophthalmichthys molitrix, Wallagu attu, Cyprinus carpio, Sperata seenghala) and five species of migratory birds (Anas strepera, Aythya ferina, Anas platyrhynchos, Anas crecca, Anas clypeata) and water of Mangla dam. Heavy metal concentration was observed with AAS' help after the samples' complete chemical digestion. The average concentration of these metals in water samples was higher than the mean values in fish and birds. Heavy metals damaged fish and birds in the same order: Cd > Cu > Cr > Pb. The results of this research will hopefully prompt further consideration on the dangers of heavy metal contamination in freshwater ecosystem.

Enhancement of shelf-life of food items via immobilized enzyme nanoparticles on varied supports. A sustainable approach towards food safety and sustainability

This study was designed to extend the shelf life of fruits and vegetables through a novel technique based on utilization of microbially driven enzyme glucose oxidase and casting a fine layer of hydrogen peroxide on the food item that protected the fruit from decay. The produced nanoparticles (ZnO, Ag) were ligated with Glucose Oxidize (GOx) purified from Aspergillus niger. Post ligation studies revealed that ligated enzymes display relatively enhanced activity. Four types of sprays were prepared in order to compare their effectiveness. Glucose oxidase/silver nanoparticles (GOx/AgNPs), glucose oxidase/zinc oxide nanoparticles (GOx/ZnONPs), AgNPs and ZnONPs sprays were applied to guava fruit samples as post-harvest therapeutic agents for a period of 15 days. Fruit quality parameters such as total suspended solids (TSS), pH, weight loss, DPPH free radical capturing performance and firmness confirms that usage of the bioconjugates especially that of GOx/ZnONP was curiously active to maintain the physical appearance of fruit well along with no such deterioration in chemical composition of fruit. Consequently, enzymes ligated on the surface of nanoparticles (ZnONP) are exceptional for extension of post-harvest shelf life of fruits such as guava.

Molecular Characterization of spa, hld, fmhA, and lukD Genes and Computational Modeling the Multidrug Resistance of Staphylococcus Species through Callindra harrisii Silver Nanoparticles

The problem of multidrug resistance in bacterial pathogens is significant and is related to the high morbidity and death rates of living things due to increased levels of beta-lactamases. Plant-derived nanoparticles have gained a great significance in the field of science and technology to combat bacterial diseases, especially multidrug-resistant bacteria. This study examines the multidrug resistance and virulent genes of identified pathogenic Staphylococcus species obtained from Molecular Biotechnology and Bioinformatics Laboratory (MBBL), culture collection. The polymerase chain reaction-based characterization of Staphylococcus aureus and Staphylococcus argenteus having ON875315.1 and ON876003.1 accession IDs revealed the presence of the spa, LukD, fmhA, and hld genes. The green synthesis of silver nanoparticles (AgNPs) was carried out by utilizing the leaf extract of Calliandra harrisii, of which metabolites act as capping and reducing agents for the precursor of nano-synthesis, i.e., AgNO₃ of 0.25 M. The synthesized AgNPs were characterized via UV-vis spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, and energy-dispersive X-ray analysis which inferred the bead-like shape of our nanoparticles with the size of 2.21 nm with the existence of aromatic and hydroxyl functional groups at surface plasmon resonance of 477 nm. The antimicrobial activity by AgNPs showed 20 mm inhibition of Staphylococcus species as compared to the vancomycin and cefoxitin antibiotics along with crude plant extract, which showed a minimum zone of inhibition. The synthesized AgNPs were also analyzed for various biological activities like anti-inflammatory with 99.15% inhibition in protein denaturation, antioxidant with 99.8% inhibition in free radical scavenging, antidiabetic with 90.56% inhibition of alpha amylase assay, and anti-haemolytic with 89.9% inhibition in cell lysis which shows good bioavailability and biocompatibility of the nanoparticles with the biological system of the living being. The amplified genes (spa, LukD, fmhA, and hld) were also analyzed for their interaction with AgNPs computationally at the molecular level. The 3-D structure of AgNP and amplified genes was retrieved from ChemSpider (ID: 22394) and Phyre2 online server, respectively. The binding affinities of AgNP with spa, LukD, fmhA, and hld were -7.16, -6.5, -6.45, and -3.3 kJ/mol, respectively, which infers a good docking score except of hld which is -3.3 kJ/mol due to its small size. The salient features of biosynthesized AgNPs proved to be an effective approach in combating the multidrug-resistant Staphylococcus species in the future.