Study on biological activities of extracts from Hedyotis diffusa Willd., Rubiaceae

Abstract

     This research aims at understanding the chemical composition, extracting, and isolating fragmented gels from Hedyotis diffusa, then surveying on the gels’ antioxidizing effects using DPPH analysis, on their anti-inflammatory effectts in vitro, and on their cytotoxic effects on human cancer cells. From 3kg of dried Hedyotis diffusa, after soaking with 70⁰ alcohol and then concentrating a total of 60 g gross extracts (cao T) was collected. After distribution shaking process of the liquid, 30.1 g petroleum ether extract (cao P), 38.6 g chloroform extract (cao C), and 20.4 g ethyl acetate extract (cao E) were collected. All had antioxidizing effects, though weaker than the compared ascorbic acid. Of the three, cao E had the highest effects with IC₅₀ value at 30.52 µg/mL. Cao T has the best NO inhibition on RA264.7 cell (IC₅₀ < 30 µg/mL). However, all test gels had strong cytotoxic effects on RAW 264.7. The results on liver cancer cells – HepG2 – and lung cancer cells – A549 – showed that cao C had the best cytotoxic effects with IC₅₀ values being 81.16 and 92.72 µg/mL perspectively. The results proved the potentials of the antioxidizing, anti-inflammatory and cytotoxic effects of the extracts, prompting the applications of Hedyotis diffusa in Medicine.