No abstract

Terminalia catappa is a widespread medium tree species in many tropical countries. While the majority of the studies up to date focuses on the aerial part of the plant such as leaf, stem bark and fruit, information about the phytochemical property as well as the biological property of the edible seed is still scarce. This study was the first to explore the fatty acid composition, antibacterial and antioxidant activities of the seed oil from T. catappa grown in Vietnam. The results showed that both the hot-pressed and cold-pressed oils contained a high level of unsaturated fatty acids such as oleic (~32%) and linoleic acids (28.38%-29.2%), as well as saturated fatty acids such as palmitic acid (~33.3%-33.61%). The presence of eicosadienoic acid in T. catappa seed oils was reported in this study for the first time. These oils displayed antibacterial activity against 5 out of 12 tested strains such as Bacillus cereus, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Vibrio parahaemolyticus. The antioxidant activity of the oils was also recorded by DPPH radical scavenging assays with IC50 values of 950 µg/ml and 2529 µg/ml for cold-pressed oil and hot-pressed oil respectively. This study has provided promising extracting methods and resulted in oils that could be good candidates for developing food sources with valuable fatty acids, antioxidant and antibacterial capacities against both Gram-positive and negative bacteria in the human diet.

In this study, biochar derived from Jackfruit peel (JA) via the pyrolysis at 500 °C for 2 h was used as an adsorbent to remove Methylene Blue (MB) from aqueous solution. Effects of pH, contact time, and initial MB concentration were investigated. Isotherm models, such as Langmuir, Freundlich, Sips, and Dubinin-Radushkevich, were applied to estimate the adsorption in nature. The results indicated that the Sips and Freundlich models gave the best fit with experimental datas. The maximum adsorption capacity of MB calculated from Langmuir was 39.87 mg/g at 306K, pH = 11, and time = 60 min. The E value evaluated from Dubinin-Radushkevich smaller than 8 kJ/mol indicated that the MB adsorption of JA followed a physical process.

A new hopan-type triterpenoic peracid, tinctoride A (1), together with three known compounds, zeorin (2), 6β,22-dihydroxyhopane (3), and ergosterol peroxide (4), was isolated from Parmotrema tinctorum (Despr. ex Nyl.) Hale. Their chemical structures were identified by extensive 1D and 2D NMR analysis and high-resolution mass spectroscopy and compared with those reported in the literature. The enzyme inhibitory potential of compounds 1–3 against α-glucosidase was investigated, exhibiting nil to weak inhibitory activity.