Chemical constituents, antioxidant, and antimicrobial activity of Allium chinense G. Don

Background: Allium chinense G. Don is a medicinal and aromatic herb belonging to the family Amaryllidaceae, characterized by a high saponin content. The previous report has mostly been focused on the bulb, and there is very limited work on the leaf. The information about biological and chemical constituent of A. chinense leaf is still inadequate in contrast to the investigations reported on the bulb. To the best of our knowledge, there is no report on the hexane extract of both bulb and leaf extract. Therefore, the present investigation was focused on identifying and characterization of the hexane extracts of A. chinense bulb and leaf quantitatively and by using the GC-MS method and to know its scavenging, antibacterial, and antifungal activity. Results: Twenty-eight bioactive compounds were identified in the bulb and nine in the leaf extract by GC-MS analysis. The versatile compounds present in the bulb are 2-methyloctacosane (21.30%), tetracontane (14.05%), eicosane, 10-methyl (12.06%), heneicosane (8.46%), octadecyl trifluoroacetate (6.48%), and 1-heneicosanol (5.76%), whereas in the leaf, it was phytol (35.76%), tetratetracontane (18.49%), perhydrofarnesyl acetone (14.76%), and heptadecane, 2,6-dimethyl (10.79%). In quantitative estimation, saponins were estimated to have the highest with 375.000 0.577mg/g in the leaf and 163.750 +/- 0.433mg/g in the bulb. The DPPH antioxidant scavenging activity was found to be minimum in both the bulb (IC50 = 678.347 mu g/ml) and leaf (IC50 = 533.337 mu g/ml). A. chinense extracts of both leaf and bulb exerted potential antibacterial effects against Staphylococcus aureus and Pseudomonas aeruginosa. Leaf extract exhibited greater antifungal activity than the bulb against Aspergillus niger. Conclusion: From the analysis, the hexane leaf extract exhibited higher antibacterial, antifungal, and antioxidant activity than the bulb. Their superior activity might be due to the higher content of total saponin and terpenes. This result will lead to further in-depth research towards the potential use of this plant; the bio-constituents can be further isolated and used in medical and therapeutic applications.