Anti-Dengue Activity of Lipophilic Fraction of Ocimum basilicum L. Stem.

Ocimum basilicum L. is used to cure many types of fever in traditional medicine. This study aims to explore the antiviral activity of the lipophilic fraction of the stem of O. basilicum (LFOB) against dengue virus (DENV) and chikungunya virus (CHIKV). The LFOB was analyzed using GC-FID and GC-MS. The antiviral activity of LFOB was studied using the Vero CCL-81 cell line. The cytotoxicity assay was performed using 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT). In vitro antiviral activity and FFU assay were used to determine and confirm antiviral activity against DENV and CHIKV. Twenty-six compounds were identified in LFOB using GC/MS. The most abundant compounds were ß-sitosterol (22.9%), stigmasterol (18.7%), and campesterol (12.9%). Significant reduction in DENV titre was observed under pre- and post-infection treatment conditions at a concentration of 3.125 µg/mL, but no anti-CHIKV activity was observed. Our earlier and the present AutoDock-Vina-based in silico docking study revealed that ß-sitosterol and stigmasterol could form strong interactions with the DENV E glycoprotein and DENV RdRp domain, respectively. Our findings suggest that LFOB can inhibit DENV infection and might act as a potent prophylactic/therapeutic agent against DENV-2. In silico results suggested that ß-sitosterol and stigmasterol may block the viral entry by inhibiting the fusion process and viral replication respectively.

Comparative evaluation of antimicrobial efficacy of chitosan nanoparticles and calcium hydroxide against endodontic biofilm of Enterococcus faecalis: An in vitro study.

Aim: The aim of the study was to assess and evaluate the antimicrobial effectiveness of chitosan nanoparticles (CSNPs) with calcium hydroxide in the elimination of Enterococcus faecalis. Materials and Methods: Using the broth microdilution method, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of calcium hydroxide and CSNPs were measured. The antibiofilm effect of calcium hydroxide and CSNPs against E. faecalis biofilm was qualitatively analyzed using a crystal violet assay. A 7-day-old biofilms of E. faecalis grown on dentine discs were assigned to the following three groups (n = 11 dentine discs), normal saline (group I), calcium hydroxide (group II), and CSNPs (group III). Quantification of live and dead cells using confocal microscopy was done to evaluate the antibiofilm efficacy of the medicaments included in the study. Results: MIC of calcium hydroxide and CSNPs against E. faecalis was observed at 2.5 mg/mL and 0.31 mg/mL, respectively. MBC of calcium hydroxide and CSNPs was observed at 2.5 mg/mL and 0.31 mg/mL, respectively. Using Crystal Violet (CV) assay, calcium hydroxide and CSNPs showed biofilm inhibition at concentrations of 2.5 mg/mL and 0.625 mg/mL, respectively. Confocal laser scanning microscopy analysis found that both calcium hydroxide and CSNPs showed a significant decrease in viable cells at their MBC values compared to the control group's normal saline. CSNPs showed a significantly lower percentage of live cells than calcium hydroxide (P < 0.05). Conclusion: The study results reveal that the antimicrobial efficacy of CSNPs is better than calcium hydroxide and normal saline against E. faecalis biofilm.

Volatile composition and antimicrobial activity of the essential oil of Artemisia absinthium growing in Western Ghats region of North West Karnataka, India.

CONTEXT: Artemisia absinthium L. (Asteraceae) is an aromatic, herbaceous, perennial plant commonly known as wormwood. Artemisia absinthium is traditionally used as an anthelmintic, antiseptic, antispasmodic and for bacillary dysentery, cancers and neurodegenerative diseases. OBJECTIVE: The essential oil composition of the leaves of A. absinthium growing in the Western Ghats region of North West Karnataka, India, is investigated for the first time in this region and the oil was screened for antimicrobial properties. MATERIALS AND METHODS: The chemical composition of the hydro-distilled essential oil obtained from the leaves of A. absinthium was analyzed by GC-FID and GC/MS. The oil was tested against five Gram positive and, eight Gram negative bacteria and three fungi by the tube-dilution method at a concentration range of 5000-9 µg/mL. RESULTS: Results demonstrated that the leave oil was found to be rich in oxygenated monoterpenes (39.7% and 41.1%). The major compounds were borneol (18.7% and 16.7%), methyl hinokiate (11.9% and 12.9%), isobornyl acetate (4.0% and 4.7%), ß-gurjunene (3.8% and 4.4%) and caryophyllene oxide (3.7% and 4.3%), among 64 identified compounds, comprising 91.7% and 90.1% of the total oil. The organism Micrococcus luteus was found more susceptible to the oil with an MIC value of 25 ± 4 µg/mL, followed by Micrococcus flavus, Bacillus subtilis, Penicillium chrysogenum and Aspergillus fumigatus with MIC values of 58 ± 8, 65 ± 8, 84 ± 15 and 91 ± 13 µg/mL, respectively. DISCUSSION AND CONCLUSION: The oil showing antimicrobial activity against bacteria and fungi validate the traditional use of the plant as an antiseptic.

Effect of different irrigants on the push-out bond strength of biodentine and TheraCal LC when used for perforation repair in simulated condition.

Background: Perforation repair materials should have excellent sealing ability and dislodgement resistance. While several materials have been employed for perforation repair, newer calcium-silicate materials, such as Biodentine and TheraCal LC, have shown promising outcomes. Aims: This study aimed to evaluate the effect of different irrigants on the dislodgement resistance of Biodentine and TheraCal LC when used for perforation repair in simulated conditions. Methods and Material: 3% sodium hypochlorite, 2% chlorhexidine gluconate, and 17% EDTA were evaluated for their effect on the dislodgement resistance of Biodentine and TheraCal LC. 48 permanent mandibular molars were selected for the study. The samples were divided into two groups: Group I - Biodentine and Group II - TheraCal LC, with 24 samples each. Statistical Analysis: The mean dislodgement resistance and standard deviation of Group I (Biodentine) and Group II (TheraCal LC) were compared and Failure pattern analysis was done. Results: Biodentine showed a significant decrease in push-out bond strength after contact with 3% NaOCl, 2% CHX, and 17% EDTA whereas, TheraCal LC showed no significant decrease in push-out bond strength after exposure to 3% NaOCl, 2% CHX, and 17% EDTA. Conclusions: Overall, TheraCal LC can be considered good perforation repair material with excellent physical and biological properties.