STUDY OF PHYTOCHEMISTRY, ANTIOXIDANT AND XANTHINE OXIDASE INHIBITORY ACTIVITIES OF FIVE PAPUA MEDICINAL PLANTS AND ISOLATION OF ACTIVE COMPOUNDS FROM SELECTED PLANT EXTRACT

• Main Author: Dirgantara, Septriyanto
• Format: Dissertations
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/73290
• Institution: Institut Teknologi Bandung

Indonesia is the second largest plant biodiversity in the world. This high biodiversity holds the potential of medicinal plants that have not been explored. One of the islands in Indonesia that has the potential for medicinal plants is Papua Province. Based on the Special Research Exploration of Local Knowledge of Ethnomedicine and CommunityBased Medicinal Plants in Indonesia (RISTOJA) conducted in Papua Province in 2017, it was found that 1,180 plants were used in traditional medicine and 885 medicinal plants were identified, consisting of over 272 types of medicinal plants. The plants used in medicine totaled 195 plants, 152 of which were identified consisting of 152 species and 87 families. Medicinal plants that were successfully collected are spread across 15 districts area covering 20 ethnicities/tribes in the province of Papua. Free radicals are compounds or molecules that contain one or more unpaired electrons in their outer atomic or molecular orbitals and cause oxidative stress. Free radicals such as reactive oxygen species (ROS) are known to be involved in the pathogenesis of various diseases. One source of free radicals is the oxidation process of xanthine or hypoxanthine by xanthine oxidase to uric acid. Scientific development, especially in the field of exploration of Papuan medicinal plants, has so far only been related to ecological, taxonomic and ethnobotanical studies, while research on phytochemical studies regarding the isolation and discovery of compounds as well as testing of antioxidant activity and xanthine oxidase inhibition is still very limited, so 5 (five) were selected. Papuan traditional medicinal plants according to regional origin and different ethnic regions representing the five region territories in Papua Province, namely thesarang semut merah plant (Myrmecodia beccarii Hook.f.) originating from the Anim Ha region; daun jilat leaf (Villebrunea rubescens) from the Saireri region; katuk hutan leaves (Breynia cernua) from the Mamta region; sampare leaves (Bridelia sp.) from the Me Pago region and dollu leaves (Dodonaea viscosa) from the La Pago region for research on phytochemical studies and testing of antioxidant activity and xanthine oxidase inhibition activity. The research went through several main steps, namely crude drug characterization, phytochemical screening, extraction, determination of total phenol and total flavonoid content, antioxidant activity test, xanthine oxidase inhibition, isolation, and biological activity evaluating of isolated compounds and characterization-identification. The crude drug of five Papuan medicinal plants contains various classes of flavonoids, tannins, quinones, phenols, saponins and steroid/triterpenoid compounds. The results of determining the crude drug characterization of five Papuan medicinal plants gave various results based on various parameters, namely the determination of ethanol-soluble extract content, water-soluble extract content, foreign matter, total ash content, acid-insoluble ash content and water content. The results of the determination of total phenolic and total flavonoid content of extracts of Papuan medicinal plants were in the range of 2.41 – 9.01 (g GAE/100 g extract) and 0.89 – 8.03 (g QE/100 g extract) respectively. Antioxidant activity test using the DPPH (2,2- diphenyl-1-picrylhydrazyl) method obtained AAI values between 0.12 – 3.20, while activity tests using the CUPRAC method obtained AAI values between 0.22 – 4.27. As a comparison, ascorbic acid with AAI DPPH and CUPRAC values were 10,20 and 11.92 respectively. In vitro xanthin oxidase (XO) inhibitory activity of Papua medicinal plant extracts using a microplate reader, the percent inhibition values varied between 9.03 – 62.36% at a concentration of 100 µg/mL. Extract of selected plant MB had IC50 values for extract of n -hexane, ethyl acetate extract and ethanol extract 182.97; 20.24 and 64.74, respectively and allopurinol standard with IC50 of 5.03 µg/mL. Isolates of MB2-1, MB2-2 and MB2-3 have been successfully isolated from ethyl acetate extract of M. beccarii (MB2). Quantitative assays showed that all isolates had antioxidant activity with AAI DPPH values of 1.40, 0.55 and 1,28 and XO inhibitory activity with IC50 of 51.26, 63.76 and 86, 84 µg/mL, respectively. Based on the results of characterization and identification by TLC-densitometry and HPLC it was known that isolate MB2-1 was caffeic acid, and based on analyzed with TLC-densitometry and nuclear magnetic resonance (RMI) isolate MB2-2 was isoliquiritigenin and isolate MB2-3 was protocatechuic acid which had antioxidant and XO inhibitory activities. The ant nest plant (M.beccarii) had the potential to be developed as a source of antioxidants and XO inhibitor from nature.