Dedy Darnaedi

New resveratrol oligomers in the stem bark of Vatica pauciflora

Abstract Five new resveratrol oligomers; pauciflorols A–C ( 1–3 ), isovaticanols B ( 6 ) and C ( 8 ), and three new oligostilbene glucosides; pauciflorosides A ( 11 ), B ( 13 ), C ( 14 ), were isolated from the stem bark of Vatica pauciflora (Dipterocarpaceae) together with known 17 resveratrol oligomers ( 4, 5, 7, 9, 10, 12 and 15–25 ) and bergenin ( 26 ). The structures of isolates were established on the basis of detailed spectroscopic analysis. The typical and characteristic spectral properties of some resveratrol oligomers were also discussed.

Stilbene derivatives from Gnetum gnemon Linn.

Four stilbene derivatives, gnemonols K and L (resveratrol trimers), M (isorhapontigenin dimer), and gnemonoside K (glucoside of resveratrol trimer) together with eleven known stilbenoids and a lignan were isolated from the acetone, methanol and 70% methanol soluble parts of the root of Gnetum gnemon (Gnetaceae). The structures of the isolates were determined by spectral analysis. The antioxidant activity of the stilbenoids on lipid peroxide inhibition and super oxide scavenging activity were also investigated.

Cycloartane triterpenoids from Aglaia harmsiana

Abstract Two new and two known cycloartane-type triterpenoids were isolated from the leaves of Aglaia harmsiana. The structures were determined using 1H, 13C and 2D NMR techniques.

Global legume diversity assessment : concepts, key indicators, and strategies

While many plant species are considered threatened under anthropogenic pressure, it remains uncertain how rapidly we are losing plant species diversity. To fill this gap, we propose a Global Legume Diversity Assessment (GLDA) as the first step of a global plant diversity assessment. Here we describe the concept of GLDA and its feasibility by reviewing relevant approaches and data availability. We conclude that Fabaceae is a good proxy for overall angiosperm diversity in many habitats and that much relevant data for GLDA are available. As indicators of states, we propose comparison of species richness with phylogenetic and functional diversity to obtain an integrated picture of diversity. As indicators of trends, species loss rate and extinction risks should be assessed. Specimen records and plot data provide key resources for assessing legume diversity at a global scale, and distribution modeling based on these records provide key methods for assessing states and trends of legume diversity. GLDA has started in Asia, and we call for a truly global legume diversity assessment by wider geographic collabora- tions among various scientists.

A New Resveratrol Hexamer from Upuna borneensis

A new resveratrol hexamer, upunaphenol A, was isolated from an acetone soluble part of stem of Upuna borneensis (Dipterocarpaceae). The structure, which has twelve asymmetric carbon atoms on the partial structures of a dibenzobicyclo[3.2.1]octadiene ring and four dihydrobenzofuran rings, was determined by spectral analysis including 1D and 2D NMR spectral experiments. Resveratrol and four known resveratrol oligomers, ampelopsin F, isoampelopsin F, vaticanols C and B, were also isolated. Upunaphenol A was found to suppress cell growth in HL60 cells through induction of apoptosis with IC 5 0 at 9.2 μM.

Five Stilbene Glucosides from Gnetum gnemonoides and Gnetum africanum

Five new stilbene glucosides, gnemonosides F, G, H, I, and J were isolated from the stem lianas of Gnetum gnemonoidesBrongn and Gnetum africanumWelw along with nine known stilbenoids. The structures of the new compounds were elucidated as gnetin E 4a,4b,4c-O-β-triglucopyranoside (2), gnetin E 4a,4c-O-β-diglucopyranoside (3), gnetin C 4a,4b,11a-O-β-triglucopyranoside (4), gnetin D 4a,4b-O-β-diglucopyranoside (5), and gnetuhainin A 4a,4b-O-β-diglucopyranoside (6) on the basis of spectroscopic evidence.

Eryvarins F and G, two 3-phenoxychromones from the roots of Erythrina variegata

Two 3-phenoxychromones, eryvarins F and G, were isolated from the roots of Erythrina variegata. Their structures were established to be 3-(2,4-dihydroxyphenoxy)-7-hydroxy-6,8-di(3,3-dimethylallyl)chromen-4-one and 3-(2,4-dihydroxyphenoxy)-8-(3,3-dimethylallyl)-2,2-dimethylpyrano[5,6:6,7]chromen-4-one on the basis of spectroscopic and chemical evidence. Eryvarins F and G are unusual 3-phenoxychromone derivatives with two isoprenoid groups.

Allozyme analysis of cryptic species in the Asplenium nidus complex from West Java, Indonesia

Abstract.In various fern species, a large amount of rbcL sequence variation has been reported, and it is possible that these species contain several reproductively isolated cryptic species. In our previous study on Asplenium nidus L., it was suggested that the plants growing in Mt. Halimun National Park, West Java, Indonesia, consist of several cryptic species based on the results of crossing experiments among rbcL sequence types. In this study, we examined allozyme polymorphisms of five rbcL sequence types found in West Java in order to test the hypothesis that the assemblages of A. nidus delimited based on the rbcL sequences are separate Mendelian populations and gene flow is disrupted by reproductive isolation from one another. The calculated fixation indices suggested that the individuals in each rbcL type are randomly crossing at least in the investigated localities. Nevertheless, these rbcL-based assemblages were genetically differentiated in allozymes that are encoded in their nuclear genomes, and it is also suggested that gene flow is disrupted even between sympatrically distributed pairs of rbcL sequence types. Therefore, our findings support the view that the five rbcL sequence types in West Java are potential cryptic species.

Stilbenoids from the stem of Gnetum latifolium (Gnetaceae)

An acetone extract of the stem of Gnetum latifolium Blume afforded the stilbene trimer (latifolol) together with five known stilbenoids (gnetin E, gnetin D, gnetin C, (-)epsilon -viniferin and resveratrol). Their structures were elucidated on the basis of spectral evidence, in particular by using 2D NMR methods.

Four New Stilbene Oligomers in the Root of Gnetum gnemon

Four new stilbene oligomers, gnemonols G, H, I, and J (1–4), were isolated from acetone extract of the root of Gnetum gnemon along with five known stilbenoids, ampelopsin E, cis-ampelopsin E, gnetins C, D, and E. The structures were elucidated on the basis of spectroscopic evidence.