Thalictrum foliolosum DC: An unexplored medicinal herb from north western Himalayas with potential against fungal pathogens and scavenger of reactive oxygen species

Evaluation of the Antifungal, Antioxidant, and Anti-Diabetic Potential of the Essential Oil of Curcuma longa Leaves from the North-Western Himalayas by In Vitro and In Silico Analysis

Essential oils (EOs) have gained immense popularity due to considerable interest in the health, food, and pharmaceutical industries. The present study aimed to evaluate the antimicrobial and antioxidant activity and the anti-diabetic potential of Curcuma longa leaf (CLO) essential oil. Further, major phytocompounds of CLO were analyzed for their in-silico interactions with antifungal, antioxidant, and anti-diabetic proteins. CLO was found to have a strong antifungal activity against the tested Candida species with zone of inhibition (ZOI)-11.5 ± 0.71 mm to 13 ± 1.41 mm and minimum inhibitory concentration (MIC) was 0.63%. CLO also showed antioxidant activity, with IC₅₀ values of 5.85 ± 1.61 µg/mL using 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging assay and 32.92 ± 0.64 µM using ferric reducing antioxidant power (FRAP) assay. CLO also showed anti-diabetic activity with an IC₅₀ of 43.06 ± 1.24 µg/mL as compared to metformin (half maximal inhibitory concentration, IC₅₀-16.503 ± 0.66 µg/mL). Gas chromatography-mass spectrometry (GC-MS) analysis of CLO showed the presence of (-)-zingiberene (17.84%); 3,7-cyclodecadien-1-one, 3,7-dimethyl-10-(1-methylethylidene)-(15.31%); cyclohexene, 4-methyl-3-(1-methylethylidene) (12.47%); and (+)-4-Carene (11.89%) as major phytocompounds. Molecular docking of these compounds with antifungal proteins (cytochrome P450 14 alpha-sterol demethylase, PDB ID: 1EA1, and N-myristoyl transferase, PDB ID: 1IYL), antioxidant (human peroxiredoxin 5, PDB ID: 1HD2), and anti-diabetic proteins (human pancreatic alpha-amylase, PDB ID: 1HNY) showed strong binding of 3,7-cyclodecadien-1-one with all the selected protein targets. Furthermore, molecular dynamics (MD) simulations for a 100 ns time scale revealed that most of the key contacts of target proteins were retained throughout the simulation trajectories. Binding free energy calculations using molecular mechanics generalized born surface area (MM/GBSA), and drug-likeness and toxicity analysis also proved the potential for 3,7-cyclodecadien-1-one, 3,7-dimethyl-10-(1-methylethylidene) to replace toxic synthetic drugs and act as natural antioxidants.

Combination between antibacterial and antifungal antibiotics with phytocompounds of Artemisia annua L: A strategy to control drug resistance pathogens

ETHNOPHARMACOLOGICAL RELEVANCE

Artemisia annua L. is a traditional Chinese medicine used for the treatment of malaria, jaundice and intense fever.

AIM OF THE STUDY

The aim of the present study was to investigate the phytochemicals, antioxidants, antimicrobial and synergistic potential of methanolic and petroleum ether extracts of A. annua against bacterial and fungal pathogens.

METHOD

Antioxidant activity of different concentrations of methanolic and petroleum ether extracts of A. annua was determined by DPPH free radical scavenging assay. Antimicrobial activity was determined by agar well diffusion, whereas MIC and synergistic activity was done by broth dilution method.TLC and GC-MS were done to identify active phytocompounds present in methanolic and petroleum ether extracts.

RESULTS

Methanolic extract of A. annua showed higher antioxidant potential (IC50 37 0.75 ± 0.34 μg ml^-1) as compared to petroleum ether extract. In antimicrobial analysis, methanolic and petroleum ether extracts of A. annua produced potent inhibitory activity against Candida strains as compared to bacterial strains. Methanolic and petroleum ether extracts of A. annua produced synergistic potential with decrease in MIC from 4 to 264 folds against bacterial (S. aureus and E. coli) and Candida strains in combination with antibacterial and antifungal antibiotics. Sub fraction I of methanolic and petroleum ether extracts was isolated through silica TLC and showed 10-fold more antimicrobial activity as compared to crude extract. GC-MS analysis of sub-fraction I of A. annua revealed 13 major phytocompounds with area more than 1%. Interestingly, 2-Propenoic acid and ridecyl ester (25.88%) were the major phytocompounds.

CONCLUSION

Phytocompounds of A. annua can be used as bioenhancer of antibacterial and antifungal agents to control drug resistance.