Bioinspired green synthesis of ZnO nanoparticles by marine-derived Streptomyces plicatus and its multifaceted biomedicinal properties.

The present study explores the bioinspired green synthesis of zinc oxide nanoparticles (ZnONPs) using marine Streptomyces plicatus and its potent antibacterial, antibiofilm activity against dental caries forming Streptococcus mutans MTCC and S. mutans clinical isolate (CI), cytotoxicity against oral KB cancer cells, hemolysis against blood erythrocytes and artemia toxicity. The bioinspired ZnONPs showed a distinctive absorption peak at 375 nm in UV-Vis spectra, the FT-IR spectra divulged the active functional groups, and XRD confirmed the crystalline nature of the nanoparticles with an average grain size of 41.76 nm. SEM analysis evidenced hexagonal morphology, and EDX spectra affirmed the presence of zinc. The ZnONPs exerted higher antagonistic activity against S. mutans MTCC (Inhibitory zone: 19 mm; MIC: 75 µg/ml) than S. mutans CI (Inhibitory zone: 17 mm; MIC: 100 µg/ml). Results of biofilm inhibitory activity showed a concentration-dependent reduction with S. mutans MTCC (15 %-95 %) more sensitive than S. mutans CI (13 %-89 %). The 50 % biofilm inhibitory concentration (BIC50) of ZnONPs against S. mutans MTCC was considerably lower (71.76 µg/ml) than S. mutans CI (78.13 µg/ml). Confocal Laser Scanning Microscopic visuals clearly implied that ZnONPs effectively distorted the biofilm architecture of both S. mutans MTCC and S. mutans CI. This was further bolstered by a remarkable rise in protein leakage (19 %-85 %; 15 %-77 %) and a fall in exopolysaccharide production (34 mg-7 mg; 49 mg-12 mg). MTT cytotoxicity of ZnONPs recorded an IC50 value of 22.06 µg/ml against KB cells. Acridine orange/ethidium bromide staining showed an increasing incidence of apoptosis in KB cells. Brine shrimp cytotoxicity using Artemia salina larvae recorded an LC50 value of 78.41 µg/ml. Hemolysis assay substantiated the biocompatibility of the ZnONPs. This study underscores the multifaceted application of bioinspired ZnONPs in dentistry.

Quantification of the Bioactivity of Ethanolic Extract From Phoenix dactylifera.

AIM: This study aims to quantitatively assess the anti-inflammatory and antioxidant activities of the ethanolic extract of Phoenix dactylifera seeds. MATERIALS AND METHODS: Around 30 seeds of Phoenix dactylifera were collected, crushed, and powdered; 10 gm of powder was added to 100 ml of ethanolic extract and boiled for further analysis. Egg albumin denaturation assay and hydroxyl radical scavenging assay were done to evaluate the anti-inflammatory and antioxidant activity, respectively. An independent t-test was used to compare the anti-inflammatory and antioxidant potential of the ethanolic extract of Phoenix dactylifera using SPSS Statistics version 22.0 (IBM Corp. Released 2013. IBM SPSS Statistics for Windows, Version 22.0; Armonk, NY: IBM Corp.), and values less than 0.05 are considered statistically significant. RESULTS: The seeds of Phoenix dactylifera have potent anti-inflammatory and antioxidant properties. Both anti-inflammatory and antioxidant properties improved with higher concentrations and were comparable to the control substances diclofenac sodium, vitamin E, and ascorbic acid, respectively. The most significant anti-inflammatory and antioxidant effect was observed at a dosage of 50 µL, with a p-value of 0.001. CONCLUSION: To conclude, we found that the ethanolic extract of Phoenix dactylifera has anti-inflammatory and antioxidant activity, which can further be used for the improvement of pharmaceuticals.