Inhibition of Oral Biofilms and Enhancement of Anticancer Activity on Oral Squamous Carcinoma Cells Using Caffeine-Coated Titanium Oxide Nanoparticles

The fungus Candida albicans is a prominent cariogenic fungal agent that works in association with Streptococcus mutans to accelerate the formation of oral cancer and tooth decay. This study evaluates caffeine-encapsulated titanium oxide nanoparticles (CF-TiO2 NPs) for their potential to prevent biofilm formation on teeth and enhance oral anticancer treatment by influencing apoptotic gene regulation. The synthesized CF-TiO2 NPs were characterized using ultraviolet, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy analyses, and their antioxidant activity was confirmed through free radical quenching studies. Antimicrobial efficacy was assessed using a zone of inhibition test, revealing strong activity against dental pathogens with a minimal inhibitory concentration of 80 µg/mL. Molecular docking using AutoDock explored interactions between CF and biofilm target sites, supporting their inhibitory potential. In vitro cytotoxicity studies on KB cancer cells showed a dose-dependent increase in cytotoxic effects, with CF-TiO2 NPs promoting apoptotic gene upregulation at concentrations of 20-160 µg/mL. CF-TiO2 NPs demonstrated excellent antioxidant, antibacterial, and anticancer properties, showcasing their promise for oral therapeutic applications. This research highlights a novel approach to managing oral infections and associated complications while improving systemic oral health. Notably, this study is the first to report the biofilm-inhibitory and anticancer potential of CF-TiO2 NPs.

Formulation of Asiatic acid-loaded polymeric chitosan-based hydrogel for effective MRSA infection control and enhanced wound healing in zebrafish models

BACKGROUND

Wound healing relies on a controlled inflammatory process vital for tissue regeneration. Chronic wounds, characterized by persistent inflammation and high infection risk, pose significant challenges in healthcare. Hydrogel dressings offer promise in wound care; however, the understanding of their role in managing inflammation and infection remains unclear. This study aimed to elucidate these processes and assess the efficacy of Asiatic acid (AA)-infused hydrogels in reducing inflammation and preventing infection. The unique properties of AA suggest its potential to modulate inflammation, promote tissue regeneration, and inhibit microbial colonization, thereby paving the way for specialized dressings that optimize healing outcomes.

METHODS

The investigation encompassed the antibacterial, anti-biofilm, antioxidant activity, and biocompatibility of AA using a fibroblast cell line. A hydrogel incorporating AA was developed and characterized through scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), contact angle analysis, tensile testing, swelling capacity, and thermal stability assessments. Biodegradability was evaluated via enzymatic degradation, alongside controlled drug release and antibacterial efficacy against MRSA. In vivo studies using a zebrafish model examined wound healing and immune response.

RESULTS

Results confirmed AA's potent antibacterial activity against MRSA and its effectiveness in disrupting mature biofilms. Additionally, AA exhibited strong antioxidant activity and biocompatibility. Morphological analysis revealed a pore structure conducive to wound healing, and the hydrogel demonstrated enhanced tensile strength, swelling properties, and thermal stability. In vivo, the AA-infused hydrogel accelerated wound closure, re-epithelialization, and immune response, supporting its potential for advanced wound care applications. In conclusion, the AA-infused chitosan hydrogel emerges as a promising candidate for advanced wound care therapies.

Dual Action of Nanostructured α-Mangostin-Copper Oxide Complexes Against Dental Pathogen Biofilms and Oral Cancer via Apoptosis Gene Modulation

The development of effective treatments for dental pathogens and oral cancer remains a significant challenge. Copper oxide nanoparticles (CuO NPs) are recognized for their strong antimicrobial properties, attributed to the synthesis of oxygen-dependent radicals. α-Mangostin (MG), a natural xanthone from mangosteen fruit, is well-known for its antioxidant, antimicrobial, and anticancer potential. The combination of CuO NPs with MG would offer a synergistic approach to enhance therapeutic efficacy. CuO-MG NPs were synthesized and characterized for their size, morphology, and surface properties. The antimicrobial efficacy of these nanoparticles was tested against oral pathogens, including Staphylococcus aureus, Enterococcus faecalis, Streptococcus mutans, and Candida albicans. Antioxidant activity was assessed using superoxide anion and hydroxyl radical anion. The anticancer potential was evaluated by examining apoptosis induction in oral cancer cell lines, focusing on the expression of key apoptotic markers such as Caspase-3, Caspase-8, and FasL. Molecular docking simulations were performed to understand the interaction between MG and biofilm receptors. The CuO-MG NPs evidenced significant antimicrobial efficacy against all tested oral pathogens, with enhanced efficacy attributed to the combined effects of CuO-induced oxidative stress and the antimicrobial properties of MG. Antioxidant assays demonstrated a dose-dependent increase in radical scavenging activity. In oral cancer cells, CuO-MG NPs significantly reduced cell viability and induced apoptosis, as evidenced by the up-regulation of Caspase-3, Caspase-8, and FasL. Molecular docking studies revealed strong binding affinities of MG to key biofilm receptors, disrupting pathogen adhesion and biofilm formation. The combination of CuO NPs and MG offers a powerful and multifaceted therapeutic approach to oral healthcare. CuO-MG NPs demonstrate synergistic antimicrobial, antioxidant, and anticancer properties, offering a potential approach for the management of oral infections and oral cancer. Further preclinical and clinical studies are recommended to ensure their safety and stability in medical applications.

Characterization and antibacterial evaluation of Eco-friendly silver nanoparticles synthesized by halophilic Streptomyces rochei SSCM102 isolated from mangrove sediment

BACKGROUND

Antimicrobial resistance has surged due to widespread antimicrobial drug use, prompting interest in biosynthesizing nanoparticles from marine-derived actinomycetes extracellular metabolites, valued for their diverse bioactive compounds. This approach holds promise for addressing the urgent need for novel antimicrobial agents. The current study aimed to characterize novel bioactive compounds from unexplored biodiversity hotspots, halophilic Streptomyces sp. isolated from mangrove sediment in the Pichavaram region, India.

METHODS AND RESULTS

Streptomyces rochei SSCM102 was conclusively identified through morphological and molecular characterization. Synthesis of silver nanoparticles (AgNPs) from Streptomyces rochei SSCM102 was characterized using various techniques, including UV-Vis, XRD, SEM, EDX, and FT-IR. The UV-Vis spectrum of the reduced AgNPs exhibited a prominent peak at 380 nm, confirming the AgNPs. The UV-Vis spectrum confirmed the synthesis of AgNP, and SEM analysis revealed a cubic morphology with sizes ranging from 11 to 21 nm. The FTIR spectrum demonstrated a shift in frequency widths between 626 cm-1 and 3432 cm-1. The EDX analysis substantiated the presence of metallic silver, evident from a strong band at 1.44 keV. The synthesized AgNPs exhibited antibacterial efficacy against human pathogens Escherichia coli (64 ± 0.32 µg/ml), Klebsiella pneumoniae (32 ± 0.16 µg/ml), and Pseudomonas aeruginosa (16 ± 0.08 µg/ml) by MIC and MBC values of 128 ± 0.64 (µg/ml), 64 ± 0.32 (µg/ml) and 32 ± 0.16 (µg/ml), respectively. Additionally, at a concentration of 400 µg/ml, the AgNPs displayed a 72% inhibition of DPPH radicals, indicating notable antioxidant capacity. The LC50 value of 130 µg/mL indicates that the green-synthesized AgNPs have lower toxicity by Brine Shrimp Larvae assay.

CONCLUSION

The study's novel approach to synthesizing eco-friendly silver nanoparticles using Halophilic Streptomyces rochei SSCM102 contributes significantly to the field of biomedical research and drug development. By demonstrating potent antibacterial properties and aligning with sustainability goals, these nanoparticles offer promising avenues for novel antibacterial therapies.

Histological validation of in-vivo larvicidal efficacy of marine Streptomyces sp. RD06 secondary metabolites against filariasis causing Culex quinquefasciatus and statistical media optimization for larvicidal derivatives production

Mosquito-borne disease pandemics, such as the Zika virus and chikungunya, have escalated cognizance of how critical it is to implement proficient mosquito vector control measures. The prevention of Culicidae is becoming more difficult these days because of the expeditious imminence of synthetic pesticide resistance and the universal expansion of tremendously invasive mosquito vectors. The present study highlights the insecticidal and larvicidal efficacy of the prospective novel actinobacterium derived from the marine Streptomyces sp. RD06 secondary metabolites against Culex quinquefasciatus mosquito. The pupicidal activity of Streptomyces sp. RD06 showed LC50=199.22 ± 11.54 and LC90= 591.84 ± 55.41 against the pupa. The purified bioactive metabolites 1, 2-Benzenedicarboxylic acid, diheptyl ester from Streptomyces sp. RD06 exhibited an LC50 value of 154.13 ± 10.50 and an LC90 value of 642.84 ± 74.61 tested against Cx. quinquefasciatus larvae. The Streptomyces sp. RD06 secondary metabolites exhibited 100 % non-hatchability at 62.5 ppm, and 82 % of hatchability was observed at 250 ppm. In addition, media optimization showed that the highest biomass production was attained at a temperature of 41.44 °C, pH 9.23, nitrogen source 11.43 mg/ml, and carbon source 150 mg/ml. Compared to control larvae, the histology and confocal microscopy results showed destruction to the anal gill, lumen content, and epithelial layer residues in the treated larvae. Utilizing an eco-friendly method, these alternative inventive insecticidal derivatives from Streptomyces sp. RD06 eradicates Culex quinquefasciatus. This study highlights the promising potential of these Streptomyces sp. RD06 secondary metabolites to develop affordable and efficacious mosquito larvicides to replace synthetic insecticides in the future.

Polystyrene nanoplastics synergistically exacerbate diclofenac toxicity in embryonic development and the health of adult zebrafish

In this study, we investigated the possible ecotoxicological effect of co-exposure to polystyrene nanoplastics (PS-NPs) and diclofenac (DCF) in zebrafish (Danio rerio). After six days of exposure, we noticed that the co-exposure to PS-NP (100 μg/L) and DCF (at 50 and 500 μg/L) decreased the hatching rate and increased the mortality rate compared to the control group. Furthermore, we noted that larvae exposed to combined pollutants showed a higher frequency of morphological abnormalities and increased oxidative stress, apoptosis, and lipid peroxidation. In adults, superoxide dismutase and catalase activities were also impaired in the intestine, and the co-exposure groups showed more histopathological alterations. Furthermore, the TNF-α, COX-2, and IL-1β expressions were significantly upregulated in the adult zebrafish co-exposed to pollutants. Based on these findings, the co-exposure to PS-NPs and DCF has shown an adverse effect on the intestinal region, supporting the notion that PS-NPs synergistically exacerbate DCF toxicity in zebrafish.

Synergistic Action of Vanillic Acid-Coated Titanium Oxide Nanoparticles: Targeting Biofilm Formation Receptors of Dental Pathogens and Modulating Apoptosis Genes for Enhanced Oral Anticancer Activity

The prevalence of bacterial and fungal infections is caused by S. aureus, S. mutans, E. faecalis, and Candida albicans are often associated with dental illnesses. In the present study, a unique strategy was used to combat these diseases by fabricating titanium dioxide nanoparticles (TiO2 NPs) conjugated with the plant-based molecule vanillic acid (VA). To confirm the structural characterization of the synthesized VA-TiO2 NPs, an extensive analysis was carried out utilizing methods such as SEM, FTIR, and XRD. Assessments for scavenging reactive oxygen species were performed to evaluate its antioxidant capability. Furthermore, a zone of inhibition test targeting pathogenic oral bacteria was used to assess the antibacterial efficacy of VA-TiO2 NPs. Molecular modeling investigations were performed to better understand the interactions among vanillic acid and dental pathogen receptors using the Autodock program. The findings indicated that VA-TiO2 NPs exhibited strong free radical scavenging activity. Additionally, they showed excellent antibacterial action towards dental pathogens, with a minimum inhibition level of 60 μg/mL. Furthermore, at doses of 15 μg/mL, 30 μg/mL, 60 μg/mL, and 120 μg/mL, VA-TiO2 NPs demonstrated concentration-dependent apoptotic impacts on human oral carcinoma cells. Apoptotic gene over-expression was identified by the molecular perspectives that revealed the anticancer mechanism of VA-TiO2 NPs on KB cells. This study highlights the promising suitability of VA-TiO2 NPs for dental applications due to their robust antioxidant, anticancer, and antimicrobial characteristics. These nanoparticles present an evident prospect for addressing oral pathogen challenges and improving overall oral health.