Phytochemicals and antioxidant activity of alcoholic/hydroalcoholic extract of Trifolium pratense

OBJECTIVE: Trifolium pratense has many healing properties, including fewer complications of menopause, cancer cell suppression, reducing blood glucose and lipids, as well as cardiovascular beneficial effects. The purpose of this study was to identify the phytochemical and mineral composition of T. pratense. METHODS: Plant aerial parts were harvested and dried, and then hydroalcoholic and alcoholic extracts were prepared. Gas chromatography–mass spectrometry (GC–MS) analytical method was used to identify volatile compounds then liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS) was used to identify polyphenols and the mineral elements were identify by inductively coupled plasma atomic emission spectrometer/ICP-AES and scanning electron microscope-energy-dispersive X-ray spectroscopy (SEM-EDS) methods. Total phenolic content (TPC) was determined based on colorimetric method, and total flavonoid content (TFC) was established based on the folin-chiocalteau reagent. Furthermore, two assays (DPPH and FRAP) were used to measure the antioxidant capacity of T. pratense ethanolic extract. RESULTS: A total of 37 polyphenols and 107 peaks were identified by LC-ESI-MS analysis, and the GC/MS method also detected 21 volatile compounds, the most important of which were methylcyclopentane, dimethylpentanal and hexadecanol. A total of 18 mineral elements, including K, Mg, Al, Si, Zn, Ni, Cu, Se, Co, Fe, Mn, and Ca in the plant, were identified ICP-AES and SEM-EDS analysis. CONCLUSION: T. pratense has many therapeutic compounds such as polyphenol (isoflavone and flavonoids), volatile compounds, and essential mineral elements, which can be formulated purely and used in the pharmaceutical and traditional medicine industries.