Resveratrol dimers from stem bark of Hopea gregaria and Their Cytotoxic Properties

Keywords: H. gregaria, Resveratrol dimers, Murine leukemia P-388 cell

Composition of the steam volatile oil from Hyptis suaveolens Poit.

ABSTRAK Minyak pati hasil persulingan wap dari bahagian atas tumbuhan Hyptis suaveolens telah dikafi dengan gabungan KG -SJ. Daripada 70 komponen yang dikesan, 38 komponen yang membentuk kirakira 86% daripada fumlah minyak tersebut telah dicamkan. $-Kariofilena wufud dalam fumlah 41% dan komponen utama yang lain ialah l,8~sineol, terpinen-4-ol, a-bergamotena, sabinena dan <x-kopaena. Kandungan kimia minyak ini berbeza daripada yang dilaporkan untuk minyak H. suaveolens dariAmerika Selatan ABSTRACT The steam volatile oil from the aerial parts of Hyptis suaveolens has been examined by combined GC-MS. Of the 70 components detected, 38 have been identified accounting for approximately 86% of the oil fi-Caryophyllene was present to 41% and l,8<incole t terpinen-4-o 1, a-bergamotene, sabinene and a -copaene were the other major components. This oil appears to be chemically distinct from the one reported from H. suaveolens collected in South America

KAJIAN FITOKIMIA Hopea mengarawan DAN IMPLIKASINYA PADA KEMOTAKSONOMI HOPEA

Nine resveratrol oligomers have been isolated from the stem bark of Hopea mengarawan i.e. diptoindonesin D (1), balanocarpol (2), ampelopsin A (3), hopeaphuran (4), heimiol A (5), parviflorol (6), a-viniferin (7), isohopeaphenol (8), and vaticanol B (9).The structures of these compounds were determined based on spectroscopic evidence such as UV, IR, 1-D, 2-D NMR and comparison with the reported data. Those compounds implied that Hopea tends to produce resveratrol dimers. Moreover, in subgenus level, besides ampelopsin A (3) and isohopeaphenol (9), resveratrol oligomers in H. mengarawan the same as in H.dryobalanoides. It indicated that H. mengarawan and H. dryobalanoid.es came from the same subgenus

RESVERATROL DIMERS FROM STEM BARK OF <i>Hopea gregaria</i> AND THEIR CYTOTOXIC PROPERTIES

Six resveratrol dimers have been isolated from the stem bark of H. gregaria, ampelopsin A (1), balanocarpol (2), ε-viniferin (3), hopeafuran (4), heimiol A (5), and parviflorol (6). The structures of these compounds were determined based on spectroscopic evidence such as UV, IR, 1-D, 2-D NMR and comparison with the reported data. These compound inventions are strengthen conclusion that Hopea tends to produce resveratrol dimers. Biological activity of those compounds against murine leukemia P-388 cells showed that ε-viniferin (3) is the most active compound with IC50 value 5.1 ± 0.3 μg/mL.   Keywords: H. gregaria, resveratrol dimers, murine leukemia P-388 cell

Cytotoxic properties of oligostilbenoids from the tree barks of Hopea dryobalanoides

A new modified stilbene dimer, diptoindonesin D (1), was isolated from the acetone extract of the tree bark of Hopea dryobalanoides, together with seven known compounds, parviflorol (2), (Ð)-balanocarpol (3), heimiol A (4), hopeafuran (5), (+)-α-viniferin (6), vaticanol

Neuroprotection and enhanced neurogenesis by extract from the tropical plant Knema laurina after inflammatory damage in living brain tissue

Inflammatory reactions in the CNS, resulting from a loss of control and involving a network of non-neuronal and neuronal cells, are major contributors to the onset and progress of several major neurodegenerative diseases. Therapeutic strategies should therefore keep or restore the well-controlled and finely-tuned balance of immune reactions, and protect neurons from inflammatory damage. In our study, we selected plants of the Malaysian rain forest by an ethnobotanic survey, and investigated them in cell-based-assay-systems and in living brain tissue cultures in order to identify anti-inflammatory and neuroprotective effects. We found that alcoholic extracts from the tropical plant Knema laurina (Black wild nutmeg) exhibited highly anti-inflammatory and neuroprotective effects in cell culture experiments, reduced NO- and IL-6-release from activated microglia cells dose-dependently, and protected living brain tissue from microglia-mediated inflammatory damage at a concentration of 30 microg/ml. On the intracellular level, the extract inhibited ERK-1/2-phosphorylation, IkB-phosphorylation and subsequently NF-kB-translocation in microglia cells. K. laurina belongs to the family of Myristicaceae, which have been used for centuries for treatment of digestive and inflammatory diseases and is also a major food plant of the Giant Hornbill. Moreover, extract from K. laurina promotes also neurogenesis in living brain tissue after oxygen-glucose deprivation. In conclusion, extract from K. laurina not only controls and limits inflammatory reaction after primary neuronal damage, it promotes moreover neurogenesis if given hours until days after stroke-like injury