Pham Thi Nhat Trinh¹, Le Tien Dung² , Pham Hong Ngoc², Nguyen Thi Thuy Trang³, Nguyen Cuu Khoa², Hoang Ngoc Anh², Alexey V Osipov⁴, Elena G Cheremnykh⁵, Yuri N Utkin⁴

Abstract

Purpose: To investigate the anti-inflammatory and antiprotozoal effects as well as chemical profile of ethanol extracts of Hedyotis diffusa (Rubiaceae) (HDE) and Scutellaria barbata (Lamiaceae) (SBE). Methods: Dried whole plants collected in Vietnam were extracted with ethanol (30 and 96 %) by maceration for 4 weeks. The resulting extracts obtained after evaporating the solvent were stored in a refrigerator at 4 oC. Mouse carrageenan-induced inflammation and mouse macrophage cell line RAW264.7 were used to assess the in vivo and in vitro anti-inflammatory activities, respectively, while ciliate, Tetrahymena pyriformis was used to determine antiprotozoal effects. Ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) was employed to analyze the chemical profiles of the extracts. Results: All the extracts manifested anti-inflammatory effects in vitro and in vivo. The HDE exhibited significantly higher in vitro anti-inflammatory activity than SBE (p < 0.05). Furthermore, in vivo anti-inflammatory activity was higher in SBE compared to HDE. Both extracts exhibited antiprotozoal effects. The 96 % ethanol extract of both plants were more active than the 30 % ethanol extracts. Analysis by UHPLC?Q?TOF-MS revealed the presence of chrysin, apigenin and apigenin derivatives, naringenin, wogonin, quercetin and quercetin derivatives, as well as scutellarin. Conclusion: The HDE and SBE extracts from Vietnam exhibit significant in vivo and in vitro anti-inflammatory activities and in addition, antiprotozoal activity against Tetrahymena pyriformis. These plants, therefore, are potential sources of antiprotozoal agents.