Phytoconstituents of the Gynura procumbens ethanol leaf extract and its fractions and their effects on viability of macrophages

Gynura procumbens (GP) is a medicinal plant with numerous beneficial pharmacological activities. The aim of this study was to identify the bioactive phytoconstituents in GP ethanol extract and hexane, chloroform, ethyl acetate, and aqueous fractions of GP, and also to evaluate the cell viability of GP ethanol extract and its fractions-treated RAW264.7 cells. The ethanol GP leaf extract was prepared and further subjected to fractionation. The cell viability of GP ethanol extract and its fractions-treated RAW264.7 cells were measured by PrestoBlue. The phytoconstituents of GP ethanol extract and its fraction were determined by using liquid chromatography-mass spectrometry (LC-MS). RAW264.7 cells exposed to the GP ethanol extract and its fractions showed significantly high proliferation and weak cytotoxic effect on the macrophages, with an average inhibitory concentration of 90% at 24, 48, and 72 hours of incubation. However, at a concentration of 10 μg/mL, the aqueous GP fraction clearly displayed anti-proliferative properties because the cell viability of aqueous GP fraction-treated RAW264.7 cells reduced to 64%, 29% and 4% after 24, 48 and 72 hours of incubation, respectively. The GP extracts and its fractions contained mainly fatty acids, flavonoids, sesquiterpenoids, and products of chlorophyll breakdown. GP ethanol extract and its fractions at certain concentrations may act as immunomodulators, as they induced promising proliferation activity of macrophages. Further studies are needed to determine either the identified chemical compounds influenced on the proliferation of macrophages solely or cooperatively.