Eurycoma longifolia is a popular folk medicine in South East Asia. This study was focused on saccharide-containing compounds including saponins, mainly because of their medical potentials. Different organic solvents such as ethyl acetate, butanol, and chloroform were used to fractionate the phytochemical groups, which were consequently precipitated in cold acetone. Solvent fractionation was found to increase the total saponin content based on colorimetric assay using vanillin and sulfuric acid. Ethyl acetate fraction and its precipitate were showed to have the highest crude saponins after acetone precipitation. The samples were shown to have anti-proliferative activity comparable with tamoxifen (IC50 = 110.6 µg/mL) against human breast cancer cells. The anti-proliferative activities of the samples were significantly improved from crude extract (IC50 = 616.3 µg/mL) to ethyl acetate fraction (IC50 = 185.4 µg/mL) and its precipitate (IC50 = 153.4 µg/mL). LC-DAD-MS/MS analysis revealed that the saccharide-containing compounds such as m/z 497, 610, 723, 836, and 949 were abundant in the samples, and they could be ionized in negative ion mode. The compounds consisted of 226 amu monomers with UV-absorbing property at 254 nm, and were tentatively identified as formylated hexoses. To conclude, solvent fractionation and acetone precipitation could produce saccharide-containing compounds including saponins with higher anti-proliferative activity than crude extract against MCF-7 cells. This is the first study to use non-toxic solvents for fractionation of bioactive compounds from highly complex plant extract of E. longifolia.

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The aim of the present study was to determine the content of phenolics, flavonoids and tannins, as well as the biological functions of propolis extracts from the stingless bee (Heterotrigona itama). The raw propolis was extracted via maceration with ultrasonic pretreatment in 100% water and 20% ethanol. The yield of ethanolic propolis extracts was about 1% higher than its aqueous counterpart. The colorimetric assays showed that the ethanolic propolis extract had about two times higher phenolics (17.043 mg GAE/g) and tannins (5.411 mg GAE/g), and four times higher flavonoids (0.83 mg QE/g). The higher phenolic content had enhanced the antiradical and antibacterial capacities of the ethanolic extract. The propolis extracts significantly exhibited higher antibacterial activity against gram-positive bacteria (Staphylococcus aureus) than gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa). However, aqueous extract was found to have a higher anticancer property based on the viability of lung cancer cells. No cytotoxic effect was observed on normal lung cells as the cell viability was maintained >50%, even the concentration of propolis extracts were increased up to 800 µg/mL. Different chemical compositions of propolis extract would show different bioactivities depending upon the individual applications. The high content of phenolics suggests that the propolis extract could be a natural source of bioactive ingredients for the development of innovative and functional foods.

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