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This study investigates the incorporation of boron carbide (B4C) filler particulates into a kenaf fiber-reinforced epoxy matrix to explore its potential in lightweight applications, focusing on antimicrobial effectiveness, mechanical integrity, thermal properties, and microstructural characteristics. The composite material was formulated by blending varying seven different concentrations of boron carbide (0–50 g) and kenaf fibers (KFs) with an epoxy resin, aiming to achieve a balance between mechanical strength and minimal weight. Antimicrobial test revealed that the composite material, consisting of kenaf fiber reinforced with B4C particulates, exhibited significant antibacterial activity against common pathogens. Mechanical testing indicated that the addition of boron carbide and kenaf fibers significantly improved the tensile strength and flexural rigidity of the composites. Specifically, enhancements in tensile strength and flexural modulus were quantitatively analyzed, showing notable increases compared to the base epoxy resin. Scanning Electron Microscopy (SEM) was employed to examine the fracture surfaces following mechanical testing, revealing improved interfacial bonding between the kenaf fibers and the epoxy matrix due to the presence of boron carbide. This microscopic analysis also highlighted areas where stress distribution was optimized, contributing to the composite's enhanced mechanical properties.

The main novelty of this research lies in combining natural fibers and mineral fillers to create a sustainable material with enhanced antimicrobial and structural properties, offering promising applications in various industries requiring eco-friendly and high-performance materials. This study investigates the fabrication and analysis of a green composite made from Cannabis sativa fiber reinforced (CSFR) with granite filler in an epoxy matrix, focusing on antimicrobial properties and structural integrity. Various amounts of granite powder (0, 3, 6, 9, 12, and 15 g) were incorporated into the epoxy matrix. The composite exhibited significant antibacterial activity was observed against E. coli. Mechanical testing revealed that the composite with 12 g of granite powder showed the best performance, with tensile strength improving by 11.4%, flexural strength by 12.3%, impact strength by 29% and hardness is improved by 17.5%. SEM analysis highlighted well-dispersed particulates and strong fiber-matrix bonding at optimal filler levels. TGA showed enhanced thermal stability, with the decomposition onset shifting from 240 °C to 280 °C and weight retention improving 90% at 350 °C. This study underscores the potential of Cannabis sativa fiber reinforced granite filler epoxy matrix composites as sustainable materials with excellent antimicrobial and structural properties for advanced applications.

Alternative to synthetic dyes containing harmful compounds, dyes derived from natural sources are gaining popularity due to their safer and eco-friendly nature. This study focuses on extracting red dye from Basella alba fruit and optimising the extraction methods, including ultrasonic bath, ultrasonic probe, and direct heating. The extracted dye was then used for dyeing cotton, silk, and leather without needing a mordant. Furthermore, the antibacterial properties of the extracted red dye were evaluated against skin bacteria. The UV–Visible spectrophotometric analysis revealed that the maximum red colour in the methanol extract (λmax 270 and λmax 542 nm) was achieved at 60 °C for 30 min using the ultrasonic water bath extraction method, followed by the ultrasonic probe and direct heating methods. The FTIR spectra confirmed the presence of flavonoids, betacyanin, and gomphrenin-I in the extracted dye. The ultrasonic dyeing process at 50 °C yielded a K/s value 6.3 for the dyed cotton, silk, and leather without using a mordant. Additionally, the fatness test indicated a high grade of 0.5–1.5 for the ultrasonic dyeing method compared to other dyeing techniques. The extracted dye exhibited significant antibacterial activity against all Pseudomonas sp. after extraction in methanol, with the highest inhibition observed against Pseudomonas sp. with a MIC of 1.56 mg/ml.

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.

Environmental consciousness motivates scientists to devise an alternative method for producing natural fiber composite materials in order to decrease the demand for synthetic fibers. This study explores the potential of a novel composite material derived from madar fiber-reinforced epoxy with porcelain filler particulates, designed specifically for biomedical instrumentation applications. The primary focus is to assess the material's structural, mechanical, and antibacterial properties. X-ray Diffraction analysis was employed to discern the crystalline nature of the composite, revealing enhanced crystallinity due to the inclusion of porcelain particulates. Fourier-Transform Infrared Spectroscopy confirmed the chemical interactions and bonding mechanisms between madar fiber, epoxy matrix, and porcelain filler. Mechanically, the composite exhibited superior properties when addition of porcelain fillers, maximum results obtain in tensile strength of 51.28 MPa, flexural strength of 54.21 MPa, and impact strength of 0.0155 kJ/m2, making it ideal for robust biomedical applications. Scanning Electron Microscopy provided detailed insights into the morphology and distribution of the reinforcing agents within the epoxy matrix, emphasizing the fibrillated structure of madar fiber and the uniform dispersion of porcelain particulates. Importantly, antibacterial assays demonstrated the composite's potential resistance against common pathogenic bacteria, which is crucial for biomedical instrumentation. Collectively, this research underscores the promising attributes of the madar fiber reinforced epoxy composite with porcelain particulates, suggesting its suitability for advanced biomedical applications.

ZnO and ZnO-Y2O3 nanocomposites (NCs) were investigated for their photocatalytic degradation of Methylene blue (MB) dye. X-ray diffraction study demonstrates that the hexagonal structure of ZnO has crystallite size compared to ZnO-Y2O3 NCs and confirms the cubic configuration of Y2O3. Scanning electron microscopy shows that the ZnO nanoparticles are spherical and ZnO-Y2O3 NCs have smaller particles with less agglomeration. The decreased recombining of excited e−/h+ of ZnO-Y2O3 NCs is confirmed over fluorescence study. ZnO-Y2O3 exhibits a more significant degradation efficiency (96%) than ZnO nanoparticles (86%) in 120 min. ZnO-Y2O3 NCs have antibacterial as well as antioxidant activity.

Using natural dyes in dyeing industries becomes an alternative to synthetic dyes, which are known to contain harmful chemicals that can pose risks to the environment and human health. This study involves the extraction of yellow dye from Cassia alata flower petals, optimization of the extraction process using an ultrasonic bath (40 KHz and an input power of 500), ultrasonic probe (390 W, 455 W, 520 W, 585 W, and 650 W), and conventional heating (heating mantle with 30 °C, 40 °C, 50 °C, 60 °C, and 70 °C), characterization of the dye, as well as dyeing (cotton, silk, and leather) without using a mordant. The extracted yellow dye was further evaluated to determine its antibacterial activity against skin bacteria. Dye extraction optimization using UV–Visible spectrophotometric analysis revealed that the maximum yellow color in methanol extract (287 and 479 nm) was obtained at 50 °C for 45 min using ultrasonic water bath extraction, followed by the ultrasonic probe and direct heating. Based on the FTIR spectra, it is evident that OH is present at approximately 3300 cm−1, while CH stretches at around 2900 cm−1. A characteristic peak at 1608 cm−1 bears a striking similarity to anthraquinonoid-based compounds. Also, using the ultrasonic water bath dyeing technique at 50 °C for 45 min, the yellow color of cotton, silk, and leather was dyed optimally. Due to effective color removal after two washings with boiling soap liquid, the dyed cotton and silk fabric displayed good washing and rubbing fastness. Regarding antibacterial activity, the dye was highly active against all pathogens after extraction in methanol. The maximum inhibition was observed against Pseudomonas sp. with a MIC value of 1.56 mg/ml.

Oral squamous cell carcinoma (OSCC) is a highly recurrent form of cancer arising from the oral epithelium, which is the result of mutational change due to etiological factors such as tobacco, smoking, chewing of areca nuts, and alcohol consumption. OSCC occurrence has been observed to be prevalent in different regions of Pacific countries and in most Asian countries. Despite the accessibility of the oral cavity, OSCC is diagnosed at an extremely late stage of pathogenic tumor node metastasis pTNM (III–IV), resulting in a poor prognosis for the individual. Therefore, it is important to make definitive, early, and efficient diagnoses. Owing to the development of omic-natured studies, the presence of proteins, transcribed elements, metabolic products, and even microflora detected in saliva helps us to select biomarkers, which is an especially exciting potential because of the availability and the non-invasive nature of sample collection. Since the discovery of circular RNA (circRNA) by Sanger sequencing, it has been reported to play a pivotal role in several human diseases, including cancer. circRNA functions as a microRNA (miRNA) sponge in the regulation of mRNA expression, forming the circRNA-miRNA regulatory axis. In the case of OSCC, overexpression of different circRNAs exhibits both tumor-progressive and tumor-suppressive effects.

This study was intended to isolate and investigate endophytic fungi and its metabolite as an active biocontrol agent. Endophytic fungal secondary metabolites are considered as an effective and environmentally friendly alternative to synthetic chemicals for integrated pest management. In this study, different parts of medicinal plant Plectranthus amboinicus (Oregano) were selected to isolate twenty-three fungal endophytes. Out of twenty-three, one isolate demonstrates potent activities against cotton leaf worm Spodoptera litura (S. litura) an insecticides resistance pest. Identification of potent isolate was attained through the morphological, sequence similarity and phylogenetic analysis of the ITS regions and confirmed as Aspergillus sojae (A. sojae). The GCMS analysis reveals the metabolites of A. sojae were rich in 2-Furancarboxaldehyde and Levoglucosenone then other compounds. The FTIR peaks of A. sojae crude extract shows the major peaks that corresponding to NH, C–H, and OH stretching and minor peaks are C–H bend (meta) and acetylenic C–H bend. FTIR analysis supports the presence of functional groups in accordance with GCMS data as dominating compound. The bioassay results showed that A. sojae metabolite affects third and fourth instar larvae of S. litura. In addition, antibiotic quality of A. sojae metabolite tested against five selective bacteria. Among five different bacteria, the maximum zone of inhibition was displayed for Escherichia coli and Staphylococcus aureus in the higher concentration of 100 μg/mL. Our resultssuggest the importance of endophytic fungal metabolites to control the pesticide-resistant insect pests.

A green, eco-friendly approach for the synthesis of silver and gold nanoparticles (AgNPs and AuNPs) using Erigeron annuus (L.) pers flower extract as both the reducing and capping agent is reported for the first time. Optimal nanoparticle production was achieved by adjusting various parameters including pH, extract concentration, metal ion concentration, and time. Initial verification of AgNP and AuNP production was done by visual observation and measuring surface plasmon spectra at 434 and 537 nm, respectively. The synthesized AgNPs and AuNPs were characterized by high resolution-transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), energy dispersive spectrophotometry (EDS), Fourier transform infrared spectroscopy (FTIR) and zeta potential. The catalytic potential of E. annuus flower extract, silver ions, synthesized AgNPs, commercial grade AgNPs, and a mixture of flower extract and AgNPs immobilized on sodium alginate hydrogel beads (Na/Al HB) was analyzed. The ability of these immobilized materials to degrade methylene blue was investigated. Commercial grade AgNPs immobilized with Na/Al HB 1.5 g/20 mL were observed to have good catalytic activity followed by a mixture of synthesized AgNPs immobilized with Na/Al HB and E. annuus flower extract immobilized with Na/Al HB at 1.5 g/20 mL.

Phytoremediation of metals from water (WM) and nutrient (NM) media exposed to waste metal cutting fluid (WMCF) along with temperature (T) and humidity (H) stress was tested using Azolla imbricata (Roxb.) Nakai. In the absence of WMCF, biomass was higher in NM than in WM during all tests. Surprisingly, opposite results were noted in the presence of WMCF, with growth failing at exposure to > 0.1% and > 0.5% in NM and WM, respectively. Further, correlation analysis of the growth data following WM exposure revealed that biomass was affected positively by T and negatively by H and metal accumulation. Simultaneously, metal accumulation was affected negatively by T and positively by H. The average accumulations of Al, Cd, Cr, Fe, Pb, and Zn across all T/H tests were 540, 282, 71, 1645, 2494 and 1110 mg·kg -1 , respectively. The observed bioconcentration factor indicated that A. imbricata acts as a hyperaccumulator or accumulator of Zn (>10) and as either accumulator (>1) or excluder (<1) of the other metals. Overall, the phytoremediation performance of A. imbricata in multi-metal-contaminated WMCF was high in WM under all environmental conditions. Therefore, the use of WM is an economically feasible approach for the removal of metals from WMCF., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)