Mosquitoes represent a considerable risk to human health due to their role in transmitting various pathogens responsible for diseases like chikungunya, malaria, dengue, and Japanese encephalitis. There is an immediate necessity to explore innovative biological strategies to combat mosquito-borne illnesses. One promising avenue in current research is the development of bioinsecticides utilizing advanced nanotechnology. Therefore, this study aimed to synthesize silver nanoparticles from the actinobacterial strain Streptomyces anthocyanicus (OR186732), isolated from the Western Ghats in Tamil Nadu, India. The AgNPs were synthesized and then characterized using UV-visible spectroscopy, identifying a prominent absorption peak at 424 nm. The identification of different functional groups within the AgNPs was confirmed through FTIR. The produced AgNPs were shown to be crystalline by XRD analysis. The nanoparticles were characterized using FESEM, HRTEM, and EDX to analyze their morphology, size, and elemental composition. The stability was assessed through Zeta potential measurements, which were measured at -0.2 mV. The synthesized AgNPs showed strong larvicidal effects against Culex quinquefasciatus (LC50 = 2.924 ppm), Aedes aegypti (LC50 = 3.245 ppm), and Anopheles stephensi (LC50 = 3.767 ppm). Furthermore, the AgNPs were observed to significantly increase the levels of antioxidant enzymes such as SOD and GPx at high concentrations. In contrast, levels of detoxifying enzymes such as AChE and GST levels were reduced. Histological analysis of mosquito larvae treated with AgNPs revealed significant damage to the midgut tissues. The research suggests that AgNPs synthesized by Actinobacteria could be an environmentally friendly option for biological mosquito control.

Biopackaging films, such as those made from Pectin, are increasingly recognized for their sustainability in fruit preservation. This study utilizes Pectin derived from grapefruit peels to create films using evaporation casting. The research investigates factors, including Pectin concentration, sorbitol, calcium ions, and acetic acid. Film morphological and structural characterizations were performed using field emission scanning electron microscopy (FE-SEM), Energy Dispersive X-ray Fluorescence (XRF) spectroscopy, and attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR). Mechanical properties such as tensile strength (TS) and elongation at break (EAB), as well as physical properties like water vapor transmission rates (WVTR), soil biodegradation, and antibacterial capacity, were evaluated for both Pectin and Pectin/AgNPs films. The results revealed that acetic acid at a concentration of 6.67 g/L converted high methoxyl Pectin to low methoxyl Pectin, which improved gel formation. The optimal film formulation consisted of 10 g/L Pectin, 0.054 g/L calcium ions, and 5 g/L sorbitol, which enhanced film mechanical strength and soil decomposition capacity. Pectin/AgNPs films showed effective antibacterial activity against both Escherichia coli and Bacillus subtilis. Additionally, weight retention and sensory tests demonstrated that Pectin/AgNPs films successfully preserved cherry tomatoes for 10 days. Overall, Pectin and Pectin/AgNPs films show significant promise for fruit preservation, emphasizing their sustainability and effectiveness.

Candida albicans is considered as an opportunistic yeast fungus that is considered as the principal reason of dangerous invasive infections with high death rates. In this research, we were the first to mycosynthesize silver nanoparticles (AgNPs) from the rhizospheric fungus Penicillium griseofulvum (PG) cell-free filtrate (CFF) and examined their antifungal effectiveness alone or in combination with the antifungal Amphotericin B (PG-AgNPs/AMB) against C. albicans. A total of 155 fungal isolates, which were recovered from the rhizosphere soil of Reseda pentagyna, belonged to fifteen species represented by five different genera. PG-AgNPs were characterized by transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), zeta potential, Xray diffraction (XRD), UV-Vis spectroscopy, and Fourier transform infrared spectroscopy (FTIR). The disc diffusion assay presented the anti-candidal activity of PG-AgNPs against C. albicans with a minimum inhibitory concentration (MIC) of 16 mu g/mL. Additionally, PG-AgNPs/AMB (16/32 mu g/mL) exhibited a potent synergistic antifungal activity with an inhibition zone of 27 mm. PGAgNPs/AMB (16/32 mu g/mL) completely inhibited morphogenesis and repressed the adherence and biofilm establishment of C. albicans by 91% and 87%, respectively. Interestingly, PGAgNPs/AMB suppressed the antioxidant-related enzymes in C. albicans by more than 80%. PGAgNPs/AMB displayed cytoplasm degeneration and damage of cell wall as examined by scanning and transmission electron microscopy. Remarkably, PG-AgNPs did not show any signs of cytotoxicity on either primary mesenchymal stem cells or human gingival fibroblast cell line HGF1. In conclusion, we identified PG-AgNPs/AMB as an innovative therapeutic candidate for the treatment of candidiasis.

Certain Aspergillus spp. release harmful byproducts known as aflatoxins. These carcinogenic toxins contaminate crops, such as groundnut, maize, and rice. This contamination poses a significant health risk and economic burden. Current control methods have limitations. This review explores the potential of silver nanoparticles (AgNPs) as a novel strategy to mitigate aflatoxin contamination (AC). The review highlights the advantages of AgNPs, such as (1) antimicrobial properties against Aspergillus flavus and Aspergillus parasiticus, the aflatoxin producers; (2) effectiveness at concentrations that do not inhibit fungal growth, potentially reducing aflatoxin production; and (3) potential for eco-friendly synthesis using plant extracts. The review also discusses the potential drawbacks of AgNPs viz. (a) environmental concerns regarding accumulation and impact on beneficial soil microbes; and (b) cytotoxicity towards various organisms, requiring further research on safety. Studies suggest AgNPs can inhibit aflatoxin synthesis by disrupting the transcription of aflatoxin biosynthesis genes, damaging the fungal cell membrane and causing leakage of cellular components, and interfering with the secondary metabolism pathway. The review concludes that AgNPs offer a promising approach for aflatoxin control. However, further research is needed to address cytotoxicity concerns and optimise their safe and effective application in agricultural settings.

This research incorporated grapefruit peel-derived Pectin and Silver nanoparticles (AgNPs) into the Chitosan-based bio-packaging film to improve its antibacterial efficacy and physical properties such as moisture content, swelling degree, and biodegradability in soil. Systematic investigations revealed that preservative films made from Chitosan 1.75 wt %, Pectin 0.55 wt %, and AgNP 31 ppm have shown a 17.5-fold reduction in swelling degree in water compared to Chitosan films. At the same time, the anti-gram-positive and anti-gram-negative bacteria capacity, the ability to retain moisture, and biodegradability in soil, have been enhanced. Low swelling degrees provided better barrier performance, extending the shelf life of packaged products by preventing the ingress of oxygen, and water vapor; on the other hand, higher moisture content improved the flexibility and handling characteristics of packaging films, making them easier to manipulate during packaging processes. These findings herald a sustainable option for eco-friendly food packaging, a critical step toward minimizing plastic waste and strengthening food preservation procedures using Chitosan-based antibacterial films enhanced with natural additives. This manuscript explores the incorporation of Pectin extracted from Vietnamese grapefruit peels and silver nanoparticles for the improvement of antibacterial and physical properties of Chitosan-based film as an alternative packaging material. The morphological and structural characteristics of formed films including Chitosan, Chitosan/Pectin, and Chitosan/Pectin/AgNPs films are determined through field emission scanning electron microscopy dispersive X-ray spectroscopy (FE-SEM-EDX) and attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR). The mechanical properties of formed films are determined through tensile strength (TS), and elongation at break (EAB). The antibacterial effectiveness of the formed packaging films is assessed through their effectiveness against Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Bacillus subtilis). Especially, the films' physical properties are determined through water contact angle (WCA), moisture content, water solubility, swelling degree (SD), the biodegradation capacity in the soil, and the actual green grape preservation ability of all formed films through the sensory state of the green grapes after 15 days of preservation. Our research concluded that preservative films made from Chitosan 1.75 wt %, Pectin 0.55 wt %, and AgNP 31 ppm have shown a 17.5-fold reduction in swelling degree in water compared to Chitosan films. At the same time, the ability to retain moisture, and biodegradability in soil, especially, the antibacterial ability, have been enhanced. These findings herald a sustainable option for eco-friendly food packaging, a critical step toward minimizing plastic waste and strengthening food preservation procedures through using Chitosan-based antibacterial films enhanced with natural additives. image

The recent emergence of drug-resistant microorganisms and the prevalence of cancer diseases are both presenting substantial global public health concerns. Silver nanoparticles (AgNPs) have attracted significant attention and are increasingly employed in diverse biomedical applications as agents with antimicrobial and anticancer properties. The study herein focused on the biogenic synthesis of AgNPs employing the cell-free filtrate of the soil-derived bacterium Streptomyces pratensis as a reducing agent. AgNPs were characterized using UV-Vis, FTIR, FE-SEM, and TEM. The study assessed both the antibacterial and anticandidal modes of action, along with the potential anticancer properties of the biosynthesized AgNPs. The spherical, 17-44-nm biosynthesized AgNPs demonstrated strong antimicrobial and antibiofilm activities against pandrug-resistant (PDR) Gram-negative Klebsiella pneumoniae and pathogenic yeast Candida albicans, both of which were isolated from immunosuppressed patients. Dose-dependent interactions between the AgNPs and their anticancer activity were observed. The IC50 values of the AgNPs against the hepatocellular (HepG2) and colon carcinoma (HCT-116) cancer cell lines were approximately 16.5 mu g/mL and 11.5 mu g/mL, respectively. Furthermore, the antimicrobial mechanism of action of AgNPs revealed distinct leakage of sugar, DNA, and proteins from the cell membrane of both K. pneumoniae and C. albicans, as well as increased ROS generation. Moreover, the TEM micrographs depicted the distortion and damage experienced by the microbial cells after exposure to AgNPs. The findings of the current study suggest that biosynthesized AgNPs have the potential to serve as alternative therapeutic agents for combating drug-resistant K. pneumoniae, the yeast C. albicans, in addition to HepG2 and HCT-116 cells.

In the pursuit of enhancing food packaging, nanotechnology, particularly green silver nanoparticles (G-AgNPs), have gained prominence for its remarkable antimicrobial properties with high potential for food shelf-life extension. Our study aims to develop corn starch-based coating materials reinforced with G-AgNPs. The mechanical properties were examined using a uniaxial tensile tester, revealing that starch coated with the highest G-AgNPs concentration (12.75 ppm) exhibited UTS of 87.6 MPa compared to 48.48 MPa of control paper, a significant (p < 0.02) 65% increase. The assessment of the WVP showcased a statistical reduction in permeability by up to 8% with the incorporation of the hydrophobic layer. Furthermore, antibacterial properties were assessed following ISO 22196:2011, demonstrating a strong and concentration-dependent activity of G-AgNPs against E. coli. All samples successfully disintegrated in both simulated environments (soil and seawater), including samples presenting G-AgNPs. In the food trial analysis, the presence of starch and G-AgNPs significantly reduced weight loss after 6 days, with cherry tomatoes decreasing by 8.59% and green grapes by 6.77% only. The results of this study contribute to the advancement of environmentally friendly packaging materials, aligning with the UN sustainable development goals of reducing food waste and promoting sustainability.