Chemical composition, antioxidant, and antibacterial activity of essential oils from Etlingera sayapensis A.D. Poulsen & Ibrahim.

Objective: To report the chemical composition and bioactivity (including antioxidant and antimicrobial activity) of essential oils from the rhizomes, stems, and leaves of Etlingera sayapensis (E. sayapensis) A.D.

Involvement of Seladin-1 in goniothalamin-induced apoptosis in urinary bladder cancer cells.

Background: Selective Alzheimer Disease Indicator-1 (or Seladin-1) is a multifunctional protein first discovered by downregulation of its expression in Alzheimer's disease. Interestingly, the expression of this protein is upregulated in several cancers, including primary bladder cancer. However, its role in cancer formation has yet to be discovered.

Synthesis of silver nanoparticles with antibacterial activity using the lichen Parmotrema praesorediosum.

Development of a green chemistry process for the synthesis of silver nanoparticles has become a focus of interest. This would offer numerous benefits, including ecofriendliness and compatibility for biomedical applications. Here we report the synthesis of silver nanoparticles from the reduction of silver nitrate and an aqueous extract of the lichen Parmotrema praesorediosum as a reductant as well as a stabilizer.

Immunomodulatory effects of 1-(6-hydroxy-2-isopropenyl-1-benzofuran-5-yl)-1-ethanone from Petasites hybridus and its synthesized benzoxazepine derivatives.

1-(6-Hydroxy-2-isopropenyl-1-benzofuran-5-yl)-1-ethanone (1), isolated from the roots of Petasites hybridus L., and a series of synthetic benzoxazepine derivatives of compound 1 (2-6) were evaluated for their immunomodulatory effects. The compounds were evaluated for their effects on the respiratory burst of human whole blood and isolated human polymorphonuclear leukocytes (PMNs) using luminol- and lucigenin-based chemiluminescence (CL) assays, and their effect on chemotactic migration of PMNs was assessed using the Boyden chamber technique.

Acuminatol and other antioxidative resveratrol oligomers from the stem bark of Shorea acuminata.

A new resveratrol dimer, acuminatol (1), was isolated along with five known compounds from the acetone extract of the stem bark of Shorea acuminata. Their structures and stereochemistry were determined by spectroscopic methods, which included the extensive use of 2D NMR techniques. All isolated compounds were evaluated for their antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (RSA) and the β-carotene-linoleic acid (BCLA) assays, and compared with those of the standards of ascorbic acid (AscA) and butylated hydroxytoluene (BHT).

5-Hy-droxy-6-[(E)-2-phenyl-ethen-yl]-5,6-dihydro-2H-pyran-2-one isolated from Goniothalamus ridleyi.

In the title compound, C(13)H(12)O(3), the pyran ring adopts a half-chair conformation with a C atom deviating from the least-squares plane of the remaining ring atoms by 0.606 (2) Å. This plane and that of the benzene ring make a dihedral angle of 44.

Goniothalamin induces coronary artery smooth muscle cells apoptosis: the p53-dependent caspase-2 activation pathway.

Goniothalamin (GN), a styryl-lactone isolated from Goniothalamus andersonii, has been demonstrated to possess antirestenostic properties by inducing apoptosis on coronary artery smooth muscle cells (CASMCs). In this study, the molecular mechanisms of GN-induced CASMCs apoptosis were further elucidated. Apoptosis assessment based on the externalization of phosphatidylserine demonstrated that GN induces CASMCs apoptosis in a concentration-dependent manner.

Papuabalanols A and B, new tannins from Balanophora papuana.

Two new dehydrohexahydroxydiphenoyl (DHHDP) esters of dihydrochalcone glycosides, papuabalanols A (1) and B (2) were isolated from the ethyl acetate extract of Balanophora papuana. Their structures were elucidated on the basis of spectroscopic data and chemical evidences. Papuabalanol A (1) showed moderate vasodilator effect on rat aorta and papuabalanol B (2) showed potent inhibition of mushroom tyrosinase and anti-melanogenesis in B16 mouse melanoma cells.

Pterulamides I-VI, linear peptides from a Malaysian Pterula sp.

Six new linear peptides, pterulamides I-VI (1-6), were isolated from the fruiting bodies of a Malaysian Pterula species. The structures were elucidated by MS and 2D NMR experiments, and the absolute configurations of the constituent amino acids established using Marfey's method. The pterulamides are mainly assembled from nonpolar N-methylated amino acids and, most interestingly, have non-amino-acid N-terminal groups, among them the unusual cinnamoyl, (E)-3-methylsulfinylpropenoyl, and (E)-3-methylthiopropenoyl groups.

Pteratides I-IV, new cytotoxic cyclodepsipeptides from the Malaysian basidiomycete Pterula sp.

Four new cyclodepsipeptides, pteratides I-IV (1-4), have been isolated from the extract of a Pterula species collected from a Malaysian tropical forest. Homonuclear and heteronuclear 2D NMR techniques as well as MS fragmentation experiments, in combination with methanolysis, determined the gross structures of the peptides and showed that pteratides I and II each contained the nonproteinogenic amino acid 4-methylproline. The absolute configurations of the amino acids in pteratides I-IV were established using Marfey's method.

A Study of the in vitro cytotoxic activity of Gelsemium elegans using human ovarian and breast cancer cell lines.

The crude methanol extracts of Gelsemium elegans leaves were assessed for their cytotoxic activity using the microculture 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for cellular viability. This study utilized two different types of human cancer cell lines, CaOV-3 (human ovarian cancer cells) and MDA-MB-231 (human estrogen receptor negative breast cancer cells), allowing for comparison of toxicity of G. elegans against these two cancer cells lines.

Dichlorinated pulvinic acid derivative from a Malaysian Scleroderma sp.

A new dichlorinated pulvinic acid derivative, methyl-3',5'-dichloro-4,4'-di-O-methylatromentate, was isolated from the fruiting body of a Scleroderma sp. The structure was determined using spectroscopic methods, and an X-ray analysis was carried out for confirmation of the structure. Compound was found to display moderate antimicrobial activity against Bacillus subtilis.

Genotoxicity of goniothalamin in CHO cell line.

Goniothalamin (GTN) is a styrylpyrrone derivative from Goniothalamus umbrosus and other Annonaceae species. It has been shown to have anti-cancer and apoptosis-inducing properties against various human tumour and animal cell lines. The compound has also been shown to be active in vivo against DMBA-induced rat mammary tumours and was reported as an anti-fertility agent in rats.

Altholactone, a novel styryl-lactone induces apoptosis via oxidative stress in human HL-60 leukemia cells.

Plant styryl-lactone derivatives isolated from Goniothalamus sp. are potential compounds for cancer chemotherapy. In this study, we have examined the mechanisms of apoptosis induced by altholactone, a stryl-lactone isolated from the Malaysian plant G.