Phytochemical Study from Hopea pubescens Ridl. (Dipterocarpaceae)

Hopea belongs to the Dipterocarpaceae family, which consists of 104 species. Peninsular Malaysia is home to the indigenous species Hopea pubescens, also referred to as Merawan Bunga. This genus is known for its potential as an antimicrobial, anti-inflammatory and therapeutic agent. The first study on H. pubescens resins has discovered four dammerane-type triterpenes. Thus, a phytochemical study of the stem bark of H. pubescens was carried out as part of the ongoing search for active components with medicinal potential in Hopea. The stem bark of H. pubescens was dried and ground into granules (2.25 kg). The granules were macerated in acetone at room temperature for 24 hours to yield crude acetone extract (25 g). Fractionation of the crude extract was executed using vacuum liquid chromatography with the mixture of n-hexane:ethyl acetate to give six fractions. Compound 1 (128 mg), a solid white precipitate, was obtained from the washing technique of fraction 1 (1.3 g) which displayed two distinct layers. Fraction 3 (4.5 g) was further purified using column chromatography with the eluent n-hexane:ethyl acetate to afford compound 2 (2 mg). The spectroscopic analyses and literature data revealed that the pure compounds are triterpene and ferulic acid derivatives, namely lupeol (1) and pentadecyl ferulate (2) respectively ([Fig. 1]). These two constituents were the first to be isolated from this species.

Fig. 1 Structure of compounds 1-2.

Funding We would like to express our greatest appreciation to the Ministry of Higher Education, Malaysia, for the financial support (FRGS/1/2022/STG04/UITM/02/24).

Publication History

Article published online:
16 November 2023