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In recent years, researchers have increasingly focused on the development of multiphase trimetallic nanocomposites (TMNC) incorporating ternary metals or metal oxides, which hold significant potential as alternatives for combatting biofilms and bacterial infections. Enhanced oral health is ensured by the innovative techniques used to effectively prevent bacterial adherence and formation of biofilm on dental sutures. In this investigation, TMNC, which consists of Pb, Ag, and Cu, was synthesized using an autoclave-assisted sonochemical technique. Following synthesis, TMNC were characterized using FTIR, XRD, BET, XPS, TGA, and Raman spectroscopy to analyze their shape and microstructure. Subsequent evaluations, including MTT assay, antibacterial activity testing, and biofilm formation analysis, were conducted to assess the efficiency of the synthesized TMNC. Cytotoxicity and anti-human oral squamous cell carcinoma activities of TMNC were evaluated using the Human Oral Cancer cell line (KB) cell line through MTT assay, demonstrating a dose-dependent increase in anti-human oral squamous cell carcinoma activity against the KB cell line compared to the normal cell line, resulting in notably high cell viability. Furthermore, an ultrasonic probe was employed to incorporate TMNC onto dental suturing threads, with different concentrations of TMNC, ultrasonic power levels, and durations considered to determine optimal embedding conditions that result in the highest antibacterial activity. The inhibitory effects of TMNC, both in well diffusion assays and when incorporated into dental suturing threads, against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria on Mueller-Hinton agar (MHA) were assessed using various concentrations of TMNC. The results of the study indicated that the efficacy of TMNC in inhibiting bacterial growth on dental suturing threads remained impressive, even at low concentrations. Moreover, an evaluation of their potential to destabilize biofilms formed by S. aureus and E. coli, the two pathogens in humans, indicated that TMNC would be a promising anti-biofilm agent.

Natural fibers derived from renewable, environmentally sustainable sources are being considered for use as reinforcements in polymer composites. The current study focuses on the fabrication of composite materials using fiber extracted from the Cissus quadrangularis (CQ) natural plant as reinforcement, an epoxy polymer as a matrix, and calcium oxide (CaO) nanoparticles as filler material, with the weight ratio of Cissus quadrangularis fiber (CQF) and CaO filler materials are varied to quantify the biological and structural effects of CQF composite. X-ray diffraction (XRD) results demonstrate a 58% amorphous zone in this composite, while Fourier transforms infrared spectroscopy (FTIR) examination revealed the hydrophobic nature, chemical bonding, and cellulose content. Because of the increased amount of chopped CQF loading in this composite, the mechanical qualities result in an average of 23% better tensile strength. Scanning electron microscopic (SEM) analysis was used to analyze the failure analysis for fiber interaction with matrix, filler, and fiber pullouts under mechanical stress. The antibacterial research revealed that this CQF composite exhibits bacterial inhibitory activity suitable for biomedical applications.

The high incidence of fungal resistance to commercial fungicides and the negative effects of chemical fungicides on the environment and human health necessitate the development of novel biofungicides for the efficient management of fungal diseases. This study aims to greenly synthesize iron oxide nanoparticles (IONPs) using the aqueous extract of Laurus nobilis leaves and characterize these nanoparticles using various physicochemical techniques. The biogenic IONPs were tested against two pathogenic strains of Alternaria alternata and compared to the metalaxyl–mancozeb fungicide. The food poisoning technique was used to assess the antifungal efficacy of the greenly synthesized IONPs and the commercial metalaxyl–mancozeb fungicide against the tested pathogenic A. alternata strains. The biogenic IONPs showed a higher antifungal efficiency against the A. alternata OR236467 and A. alternata OR236468 strains at concentrations of 800 ppm compared to metalaxyl– mancozeb fungicide, with relative growth inhibition percentages of 75.89 and 60.63%, respectively. The commercial metalaxyl–mancozeb fungicide (800 ppm) showed growth inhibition percentages of 72.23 and 58.54% against the same strains. The biogenic IONPs also showed potential antioxidant activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, with DPPH inhibition percentages of 34.61% to 83.27%. In conclusion, the biogenic IONPs derived from L. nobilis leaves have the potential to be employed as biofungicides for the effective control of fungal phytopathogens, reducing reliance on harmful chemical fungicides.

The green synthesis of silver nanoparticles (AgNPs) using plants has grown in significance recently. The present investigation involved the synthesis of AgNPs utilizing Tabebuia rosea (TR) seeds as a reducing agent. The bioactive potential of the synthesized AgNP was evaluated through antibacterial, antioxidant, and cytotoxicity assays. The confirmation of the formation of AgNPs was achieved through the utilization of UV–vis spectroscopy. The spectroscopic analysis revealed the presence of absorption maxima at 450 nm, which is a distinctive feature of AgNPs. The optimization process for the synthesis of nanoparticles was conducted by varying the pH levels, metal ion (AgNO _3 ), and substrate (Seed extract). The size range of the synthesized nanoparticles was found to be less than 100 nm through the use of scanning electron microscopy (SEM). The profile obtained through energy dispersive x-ray spectroscopy (EDX) analysis of AgNPs exhibited a characteristic optical absorption peak at approximately 3 keV. Further investigation using Fourier transform infrared (FTIR) spectroscopy revealed the involvement of O–H stretching in phenolic compounds and O–H and C=O stretching in carboxylic acids forming AgNPs. The results of the antimicrobial activity assay indicate that the bacteria K. pneumonia exhibited the maximum inhibition zone of 20 ± 0.48 mm, followed by E. faecalis , P. aeruginosa , P. mirabilis , and S. aureus at the highest concentration of 100 mg ml ^−1 , respectively. The DPPH assay findings suggest that the maximum concentration of 500 μ g ml ^−1 of AgNPs exhibited a unique scavenging ability, with a value of 80.98%. Additionally, the application of biologically synthesized AgNPs to treated cells resulted in a cytotoxic effect. The inhibitory concentration (IC _50 ) value of 45 μ g ml ^−1 was determined following a 24 h treatment with human fibroblast cells (L929). Using T. rosea seed to produce AgNPs holds promise for their potential application as nano drugs.

To assess the antifungal activity of the crude aqueous extract of B. carteri. Three independent concentrations (1%, 2.5%, and 5%) of the crude aqueous extract of B. carteri were tested for their in vitro activity against selected fungal strains. The treated (5% concentration) and untreated A. alternata samples were analyzed for morphological changes using scanning electron microscopy (SEM). Fourier-Transform Infrared (FTIR) spectrometry of the extract was done to identify the phytoconstituents responsible for the antifungal activity. Results showed that the crude aqueous extract of B. carteri inhibited the growth of all the selected fungal species. The percentage of mycelial growth of the tested fungi decreased as the concentration of the aqueous extract increased from 1% to 5%. SEM-based studies of A. alternata treated with 5% showed significant morphological changes including shrunken hyphae, membrane disintegration, and distorted conidial structures compared to the untreated fungal cells. The crude aqueous extract of B. carteri has the potential to be used as a natural and effective fungicidal agent for controlling the growth of pathogenic fungi.

Plant growth-promoting endophytic bacteria can stimulate the growth, nutrient acquisition, symbiotic performance and stress tolerance of chickpea plants under saline soil conditions. The aim of this study was to investigate the stress-adaptive mechanisms of chickpea plants mediated by Bacillus subtilis (BERA 71) under saline conditions. Inoculation with BERA 71 enhanced plant biomass and the synthesis of photosynthetic pigments and reduced the levels of reactive oxygen species (ROS) and lipid peroxidation in plants under conditions of stress. Furthermore, the activities of ROS-scavenging antioxidant enzymes (superoxide dismutase, peroxidase, catalase and glutathione reductase), the levels of non-enzymatic antioxidants (ascorbic acid and glutathione) and the total phenol content were increased in stressed plants during bacterial association. The bacteria decreased sodium accumulation and enhanced the nitrogen, potassium, calcium and magnesium content in the plants. The suppression of ROS generation and of lipid peroxidation and the accumulation of proline in BERA-71-inoculated plants enhanced the membrane stability under salinity stress and non-stress conditions.