Hepatoprotective and Antioxidant Activities of Phenolic Compounds from Heliciopsis terminalis

Objective Heliciopsis terminalis (Kurz.) Sleum (family Proteaceae) is distributed in India, Mianma, Thailand, Cambodia, Vietnam, and China. In Vietnamese traditional medicine, it is used as an antidote for detoxifying the liver and detoxifying alcohol, a contraceptive, and to treat infections. The purpose of this study is to determine the chemical constituents of the plant, as well as their in vitro hepatoprotective and antioxidant activities. Methods The dried powdered sample was ultrasonically extracted with MeOH, and the extract was fractionated by various chromatographic methods, including high-performance liquid chromatography. The structures of the isolated compounds were identified by NMR, high-resolution electrospray ionization mass spectrometry, and CD spectral analysis, and then screened for their in vitro hepatoprotective and antioxidant activities. Results One new phenolic glycoside, named helitermioside (1), and eight known compounds (2-9) were isolated from the trunk and branches of H terminalis. All of the isolates were reported from H terminalis for the first time. Compound 6 showed antioxidant activity in thiobarbituric acid reactive substances (TBARS) lipid peroxidation inhibition assays, with an IC 50 value of 61.16 ± 1.17 µg/mL, compared to that of Trolox (positive control), IC 50 = 7.06 ± 0.11 µg/mL. At a concentration of 100 µg/mL, none of the isolates exhibited hepatocellular protective activity. Conclusion Nine phenolic compounds (1–9) were recorded from H terminalis. Of these, compound 1 was new. Compound 6 exhibited moderate antioxidant activity in TBARS lipid peroxidation inhibition assays, but none of the compounds exhibited hepatocellular protective activity against CCl 4 -induced toxicity.