@article {785, title = {Triterpenes and Sterols from Leaves of Hoya meliflua Merr}, journal = {Pharmacognosy Journal}, volume = {11}, year = {2019}, month = {January 2019}, pages = {48-52}, type = {Original Article}, chapter = {48}, abstract = {

Introduction: Hoya plants are also called wax plants due to the waxy appearance of their leaves and flowers. Most species are cultivated as ornamental plants. In the Philippines, there are at least 109 species of Hoya; 88 of these are endemic to the country. One of the endemic species is Hoya meliflua often confused with H. diversifolia, which can also be found in other countries. This study is part of our research on the chemical constituents of Philippine native Hoyas. Methods: The compounds were isolated by silica gel chromatography and identified by NMR spectroscopy. Results: Chemical investigation of the dichloromethane extract from the leaves of Hoya meliflua afforded squalene and mixtures of β-amyrin (1a), α-amyrin (1b) and lupeol (1c) in about 1:1:0.25 ratio; oleanone (2a), ursenone (2b) and lupenone (2c) in about 1:1:0.3 ratio; β-amyrin cinnamate (3a), α-amyrin cinnamate (3b) and lupenyl cinnamate (3c) in about 0.5:0.3:1 ratio; and β-sitosterol and stigmasterol in about 5:1 ratio. Conclusion: The results of our study indicate that Hoya meliflua shares similar chemical characteristics with other members of the genus Hoya. The triterpenes and sterols obtained from H. meliflua were also identified from other Hoya species. It is interesting to note that although most Hoya plants have no known biological activity and medicinal property, the compounds isolated from H. meliflua possess diverse bioactivities.

}, keywords = {Apocynaceae, Hoya meliflua, Lupenone, Lupenyl Cinnamate, Lupeol, Oleanone, Squalene, Stigmasterol, Ursenone, α-amyrin, α-amyrin Cinnamate, β-amyrin, β-amyrin Cinnamate, β-sitosterol}, doi = {10.5530/pj.2019.1.9}, author = {Vincent Antonio S. Ng and Raymond S. Malabed and Fernando B. Aurigue and Consolacion Y. Ragasa} } @article {218, title = {Cytotoxic Compounds from Kibatalia gitingensis (Elm.) Woodson}, journal = {Pharmacognosy Journal}, volume = {9}, year = {2017}, month = {December 2016}, pages = {8-13}, type = {Original Article}, chapter = {8}, abstract = {

Ursolic acid (1), squalene (2), a mixture of \α-amyrin acetate (3a) and lupeol acetate (3b), and isoscopoletin (4), isolated from the dichloromethane extracts of the leaves and twigs of Kibatalia gitingensis, were evaluated for their cytotoxic activities against three human cancer cell lines, breast (MCF-7) and colon (HT-29 and HCT-116), and a normal cell line, human dermal fibroblast-neonatal (HDFn), using the in vitro PrestoBlue cell viability assay. Compounds 1-4 exhibited strong cytotoxic activities against HT-29 cells with IC50 values ranging from 0.6931 to 1.083 \μg/mL. Furthermore, 1-4 were moderately cytotoxic against HCT-116 cells with IC50 values ranging from 4.065 to 11.09 \μg/mL. These compounds were least cytotoxic against MCF-7 cells with IC50 values ranging from 8.642 to 25.87 \μg/mL. The most cytotoxic against HT-29 cells, HCT-116 cells and MCF-7 cells are 2, 4 and 1, respectively.

}, keywords = {Apocynaceae, Cytotoxicity, HCT-116, HDFn, HT-29, Isoscopoletin, Kibatalia gitingensis, Lupeol acetate, MCF-7, PrestoBlue{\textregistered} cell viability assay., Squalene, Ursolic acid, α-amyrin acetate}, doi = {10.5530/pj.2017.1.2}, author = {Mariquit M. De Los Reyes and Glenn G. Oyong and Vincent Antonio S. Ng and Chien-Chang Shen and Consolacion Y. Ragasa} }