Tentative Identification of Phytochemicals from Smilax glabra and Smilax corbularia Extracts by LC-QTOF/MS and Their Bioactive Potential

Abstract

The Smilacaceae family has been used as a food source and herbal medicine for a long time. This study aims to identify the phytochemicals extracted from Smilax glabra and Smilax corbularia by using LC-QTOF/MS analysis and determine their bioactive potential. Compounds were identified from S. glabra and S. corbularia extracts by LC–QTOF-MS and it was found that longistylin A and CAY10435 have higher degrees of matching compounds (99.66% and 99.87%). Smilax glabra showed antioxidant capacity, i.e., DPPH and ABTS at percentage inhibitions of 71.94 ± 1.46% and 59.84 ± 4.80%, respectively, and FRAP at 730.69 ± 33.62 mg AAE/100 g sample. The total phenolic compound contents of the ethanol, methanol, and water extracts were 0.017 ± 0.001, 0.015 ± 0.001, and 0.016 ± 0.001 mg GAE/g, respectively, while the total flavonoid contents were 0.043 ± 0.002, 0.033 ± 0.002, and 0.006 ± 0.003 mg QE/g, respectively. The anti-inflammatory capacity showed 97.26% protection and 2.74% hemolysis. The antimicrobial activity can inhibit Gram-positive bacteria with a minimum inhibitory concentration (MIC) of 62.5 mg/mL and a minimum bactericidal concentration (MBC) of 500 mg/mL. Smilax corbularia showed antioxidant capacity, i.e., DPPH and ABTS at percentage inhibitions of 72.24 ± 0.64% and 39.87 ± 2.37%, respectively, and FRAP at 208.33 ± 50.80 mg AAE/100 g sample. The total phenolic compound contents of the ethanol, methanol, and water extracts were 0.006 ± 0.000, 0.007 ± 0.002, and 0.002 ± 0.001 mg GAE/g, respectively, while the total flavonoid contents of the ethanol and methanol extracts were 0.012 ± 0.001 and 0.008 ± 0.000 mg QE/g, respectively. The anti-inflammatory capacity showed 96.64% protection and 3.36% hemolysis. The antimicrobial activity of the extracts can inhibit Gram-positive bacteria with a MIC of 31.25 mg/mL and MBC of 125 mg/mL for the ethanol extract and a MIC of 125 mg/mL and MBC of 62.5 mg/mL for the methanol extract. In conclusion, Smilax glabra and Smilax corbularia were found to contain several phytochemicals that can be used for further study. Both Smilax species can also be used as sources of antioxidants and herbal medicines for killing Gram-positive bacteria.