No abstract

From the fruit of Pandanus tectorius Parkinson ex Du Roi, one new (1) and six known aldehyde compounds (2-7) were isolated by various chromatography methods. Based on their spectroscopic data, these compounds were identified as (Z)-4-hydroxy-3-(4-hydroxy-3-methylbut-2-en-1-yl) benzaldehyde (1), p-hydroxybenzaldehyde (2), syringaldehyde (3), (E)-ferulaldehyde (4), (E)-sinapinaldehyde (5), vanillin (6) and 5-hydroxymethylfurfual (7). The α-glucosidase inhibitory activity of all compounds was measured. The isolated compounds (1-6) showed better α-glucosidase inhibitory activity (IC50 values ranging from 36.5 to 192.4 μM) than the standard drug acarbose (IC50 = 214.5 μM).

In this work, two common Vietnamese Euphorbia plants, Euphorbia tirucalli Linn. (the milk bush) and Euphorbia tithymaloides Linn. (the milk hedge), have been investigated for potential use as biofuels. Their aerial parts were macerated with different solvents [petroleum ether, ethyl acetate (EA), methanol and water] to obtain extracts. The extracts were put through petrochemical composition analyses, including elemental analysis, Fourier transform infrared spectra recording and fatty acids composition analysis by HPLC. Subsequently, extracts were subjected to thermal gravimetric analysis for determination of some petrochemical contents. In addition, the gross calorific values (GCVs) of all extracts were determined and compared with those of other Euphorbia species and fuels. The obtained results showed the high petrochemical properties of Euphorbia tirucalli and moderately high ones of Euphorbia tithymaloides. Their estimated total rubber content values were then determined and compared with those of strains of other countries. The petroleum ether extract possessed the highest GCV, followed by the EA extract of E. tirucalli, then the EA extract of E. tithymaloides. Their GCVs were higher than those of some of other Euphorbia plants, conventional fuels like anthracite or lignite, and asymptotic to those of present fuels, including diesel and gasoline. Together with the plants’ well‐known tolerance of harsh conditions, such interesting phytochemical and petrochemical results significantly contribute to the potential for biofuel exploitation of Vietnamese E. tirucalli and E. tithymaloides.