Extreme effects of Seabuckthorn extracts on influenza viruses and human cancer cells and correlation between flavonol glycosides and biological activities of extracts

Seabuckthorn is a medicinal plant that is used to prevent cold. It was tested for its metabolic content followed by activity against cancer and virus. The metabolic distribution of different polarity solvent extractions from the leaves was analyzed by LC–MS/MS. Flavonol glycoside contents in EA and Bu extracts were higher than MeOH and DW was observed. MeOH and EA extracts recorded high activity against influenza A/PR virus with IC₅₀ of 7.2 μg/mL and 10.3 μg/mL compared with known drug Oseltamivir of 60.3 μg/mL. A similar trend showed in influenza A/Victoria virus. In case of influenza B viruses such as B/Lee and B/Maryland, EA extract (2.87 μg/mL and 4.5 μg/mL of IC₅₀) emerged strongest among other extracts and Oseltamivir (103.73 μg/mL and 71.6 μg/mL). Each extract showed potent anticancer activities. Interestingly, Bu extract showed stronger anticancer activity against human cancer cells such as NCL-H1299, HeLa, SKOV and Caski (8.2 μg/mL, 8.6 μg/mL, 18.2 μg/mL and 9.2 μg/mL of IC₅₀) respectively. Correlation study reveals that aglycones and flavonol mono-glycosides highly correlated with anti-influenza activities but not correlated with anticancer activities. Reversely, di-glycosides and tri-glycosides have a high correlation with cytotoxic effect with both normal and cancer cells. Therefore, this study provides significant information concerning Seabuckthorn for further medicinal drug development.