Antioxidant, antimicrobial, and GC-MS profiling of Saussurea obvallata (Brahma Kamal) from Uttarakhand Himalaya

Abstract

Abstract Background Saussurea obvallata (DC.) Edgew. (S. obvallata) is an endangered medicinal herb of the high altitude Himalayan region with immense cultural significance. This study is one of the first report of pharmacological evaluation and GC-MS analysis of methanolic extracts of leaves and flowers of S. obvallata. Methods Total flavonoid content (TFC) and total phenolic content (TPC) were performed according to standard protocols. The antioxidant activities of both the extracts (methanol and aqueous) were examined using two complementary methods, namely diphenylpicrylhydrazyl (DPPH) and Hydrogen peroxide (H2O2) assay. While, antimicrobial potential examined by using classical assays on pathogenic microbial strains along with appropriate controls of antimicrobial agents. Gas Chromatographic-Mass Spectrometric analyses of methanolic extracts of S. obvallata were performed for the identification of bioactive components. Statistical analysis was performed by using SPSS version 16.0. Results The extracts of leaves and flowers of S. obvallata showed significant results for all pharmacological experiments. TPC was recorded from a range of 132.67 ± 0.17 to 358.67 ± 0.17 mg GAE gm− 1 dw while TFC was recorded from a range of 65.73 ± 1.55 to 326.88 ± 2.11 mg QE gm− 1 dw. Per cent DPPH free radical scavenging activity was recorded from a range of 29.25 ± 0.86 to 82.88 ± 0.48% whereas per cent H2O2 free radical scavenging activity were recorded from a range of 39.75 ± 0.36 to 41.05 ± 0.46%. Antimicrobial activity was analyzed against four bacterial strains and three fungal strains. S. obvallata extracts showed fine zone of inhibition against Pseudomonas aeruginosa, Klebsiella pneumoniae and Staphylococcus aureus, but Escherichia coli showed resistant (in terms of lower zone) against the extract compared to three bacteria. In antifungal activity, extract showed maximum zone of inhibition against Candida glabrata followed by Candida albicans and Candida tropicalis. GC-MS analysis of methanolic extracts of leaves and flowers of S. obvallata showed the presence of 36 and 48 components, respectively, based on retention time (Rt), and area per cent. Conclusion These findings confirm the traditional claims and contribute in providing promising baseline information for the pharmacological use of S. obvallata. Additional highly developed research is essential for isolation and identification of specific active components which are responsible for pharmacological properties of the plant.

Keywords

• Antioxidant
• Antimicrobial
• Microbial strains
• Pharmacological evaluation
• Saussurea obvallata
• Traditional claims