Abstract

• Curcuma caesia Roxb. commonly known as Sanwin tain pyar or black turmeric, is one of the important and endangered species in the genus of Curcuma. The present study aimed to conduct phytochemical screening, isolating some organic compounds and evaluating the biological activities of the Myanmar medicinal plant C. caesia rhizome, including antidiabetic and anti inflammatory properties. The preliminary phytochemical screening of the rhizome of C. caesia showed the presence of alkaloids, glycosides, phenolic compounds, polyphenols, saponin and terpenoids. Five pure compounds (HHS-1, 2, 3, 4 and 5) were isolated from the n-hexane extract of C. caesia by using thin layer and column chromatographic separation methods. The isolated compound (HHS-1) was identified as zederone based on FT IR and UV-vis spectral data and melting point (152-153 ºC). Four extracts and the isolated HHS-1 compound were tested for antidiabetic activity using the Cirillo VP method (Glucose Uptake Capacity by Yeast Cells). The test revealed that the ethyl acetate extract and the HHS-1 compound exhibited the highest antidiabetic activity. Furthermore, the anti-inflammatory effect of the compound HHS-1 was determined by the Croton oil-induced ear oedema method. Topical application of the compound HHS-1 showed significant inhibition of the induced ear oedema (39 % for 0.75 mg/ear, 44 % for 1.5 mg/ear and 98 % for 2.25 mg/ear). This study will support further investigations on the pharmacological activity of medicinal plant species in Myanmar.