A new diarylhexane and two new diarylpropanols from the roots of Knema globularia.

A new diarylhexane, kneglobularone B (1) and two new diarylpropanols, kneglobularols A - B (2 - 3) along with seven known compounds (4 - 10) were isolated and characterized from the roots of Knema globularia. It is the first time to find arylpropyl quinone (4) and isoflavone (8) in Myristicaceae family. In addition, 5 was found for the first time in Knema genus. Their structures were elucidated by UV, IR, MS, 1 D and 2 D NMR techniques. Compound 4 exhibited strong cytotoxicity against the NCI - H187 and MCF - 7 cell lines with IC50 values of 3.08 and 6.68 µg/mL, respectively.

Phytochemicals from twigs of Afzelia xylocarpa and their antioxidation kinetics of oxymyoglobin.

The phytochemical investigation of crude n-hexane and ethyl acetate extracts from twigs of Afzelia xylocarpa (Kurz) led to the isolation of 14 known compounds. Their structures were elucidated by spectroscopic techniques (IR, 1H NMR, 13C NMR, and 2D NMR) as well as mass spectrometry. These structures were characterized as ß-sitosterol (1), lupeol (2), vanilic acid (3), 5,7-dihydroxychromone (4), (+)-mellein (5), isoliquiritigenin (6), 7-hydroxyemodin (7), physion (8), aromadendrin (9), naringenin (10), apigenin (11), luteolin (12), chrysoeriol (13) and kaempferol (14). Compounds 4-7 and 12-13 were isolated from the genus Afzelia for the first time. The selected compounds 5, 8, 9 and 12 exhibited potent activity for antioxidation kinetics of oxymyoglobin.

1H NMR metabolic phenotyping of Dipterocarpus alatus as a novel tool for age and growth determination.

Dipterocarpus alatus belongs to Family Dipterocarpaceae that can be commonly found in Southeast Asian countries. It is a perennial plant with oval-shaped leaves and oleoresin-rich wood. It has been considered as a multipurpose plant since all parts can be practically utilized. One of the major problems for utilizing Dipterocarpus alatus is the difficulty knowing the exact age as this kind of plant is ready for multipurpose use after 20 years of age. At present, the most commonly used method for determining age of Dipterocarpus alatus is the annual ring estimation. However, this conventional method is unable to provide the high precision and accuracy of age determination due to its limitation including blurry annual rings caused by enriched oleoresin in the wood. The current study aimed to investigate the differences of 1H -NMR spectroscopy-based metabolic profiles from bark and leaf of Dipterocarpus alatus at different ages including 2, 7, 15 and 25 years. Our findings demonstrated that there is a total of 56 metabolites shared between bark and leaf. It is noticeable that bark at different ages exhibited the strongest variation and sugar or sugar derivatives that were found in higher concentrations in bark compared with those in leaf. We found that decreasing levels of certain metabolites including tagatose, 1'kestose and 2'-fucosyllactose exhibited the promising patterns. In conclusion, panel metabolites involved in the sucrose biosynthesis can precisely determine the age and growth of Dipterocarpus alatus.

A 2H-tetrahydropyran derivative and bioactive constituents from the bark of Goniothalamus elegants Ast.

A new 2H-tetrahydropyran derivative, 6-epi-goniothalesdiol A (1), together with nine known styryllactones (2-10) and five known aristolactams (11-15) were isolated from the bark of Goniothalamus elegants Ast. The structures were elucidated by spectroscopic methods. The isolated compounds were evaluated for their cytotoxicity toward the KB, MCF7 and NCI-H187 cell lines as well as antimalarial and antimycobacterial activities. Compounds 4 and 10 showed strong activity against all three human cancer cell lines with IC50 values in the range of 0.538 to 4.25 µg/ml, while compounds 2, 4, 10 and 14 showed potent cytotoxicity against NCI-H187 with IC50 values in the range of 0.072 to 2.17 µg/ml. In addition, compounds 4, 6, 7, 9, 10 and 13 showed strong antiplasmodial activity with IC50 in the range of 2.28 to 5.89 µg/ml.

New lignan esters from Alyxia schlechteri and antifungal activity against Pythium insidiosum.

Three new lignan esters, alyterinates A-C (1-3), as well as 10 known compounds were isolated from the roots of Alyxia schlechteri. Antifungal activity against Pythium insidiosum of all lignan derivatives was evaluated using disk diffusion assay. P. insidiosum is not a true fungus since its cell walls do not contain ergosterol as usual fungi, so the antifungals available now are not effective. From activity testing, it was found that compounds 3, 4 and 5 could inhibit the mycelia growth of P. insidiosum.