Time filter

Source Type

Petaling Jaya, Malaysia

Tang S.W.,University Putra Malaysia | Sukari M.A.,University Putra Malaysia | Neoh B.K.,Sime Darby Technology Center | Yeap Y.S.Y.,University Putra Malaysia | And 3 more authors.
BioMed Research International | Year: 2014

Phytochemical investigation on rhizomes of Kaempferia angustifolia has afforded a new abietene diterpene, kaempfolienol (1) along with crotepoxide (2), boesenboxide (3), 2′-hydroxy-4,4′,6′-trimethoxychalcone (4), zeylenol (5), 6-methylzeylenol (6), (24S)-24-methyl-5α-lanosta-9(11), 25-dien-3β-ol (7), sucrose, β-sitosterol, and its glycoside (8). The structures of the compounds were elucidated on the basis of spectroscopic methods (IR, MS, and NMR). Isolation of 6-methylzeylenol (6), (24S)-24-methyl-5α-lanosta-9(11), 25-dien-3β-ol (7), and β-sitosterol-3-O-β-D-glucopyranoside (8) from this plant species has never been reported previously. The spectroscopic data of (7) is firstly described in this paper. Cytotoxic screening indicated that most of the pure compounds tested showed significant activity with (4) showing the most potent activity against HL-60 (human promyelocytic leukemia) and MCF-7 (human breast cancer) cell lines. However, all extracts and most of the pure compounds tested were found to be inactive against HT-29 (human colon cancer) and HeLa (human cervical cancer) cell lines. Similarly, none of the extracts or compounds showed activity in the antimicrobial testing. © 2014 Sook Wah Tang et al.

Keat N.B.,Sime Darby Technology Center | Umar R.U.,University Putra Malaysia | Lajis N.H.,University Putra Malaysia | Chen T.Y.,University Putra Malaysia | And 3 more authors.
Malaysian Journal of Analytical Sciences | Year: 2010

Spermacoce articularis and Spermacoce exilis are weeds commonly growing in wastelands but widely used as traditional medicines. The separation works on the two plant species had been carried out using various solvents and chromatographic methods. The structures of the isolated compounds were determined by using spectroscopic methods such as IR, MS, 1H NMR, 13C NMR, 2D-NMR and by comparison with the data reported previously. Extracts from Spermacoce articularis gave two compounds, identified as ursolic acid (1) and stigmasterol, while extracts from Spermacoce exilis yielded four compounds, ursolic acid (1), benzo[g]isoquinoline-5,10-dione (2), stigmasterol and hexadecanoic acid (3). There was no previous phytochemical investigation on Spermacoce exilis.

Cheah S.-C.,University of Malaya | Appleton D.R.,University of Malaya | Appleton D.R.,Sime Darby Technology Center | Lee S.-T.,University of Malaya | And 3 more authors.
Molecules | Year: 2011

In the present study we investigated the effects of panduratin A, isolated from Boesenbergia rotunda, on proliferation and apoptosis in A549 human non-small cell lung cancer cells. Cell proliferation and induction of apoptosis was determined by the real-time cellular analyzer (RTCA), MTT assay and High Content Screening (HCS). The RTCA assay indicated that panduratin A exhibited cytotoxicity, with an IC50 value of 4.4 μg/mL (10.8 μM). Panduratin A arrested cancer cells labeled with bromodeoxyuridine (BrdU) and phospho-Histone H3 in the mitotic phase. The cytotoxic effects of panduratin A were found to be accompanied by a dose-dependent induction of apoptosis, as assessed by DNA condensation, nuclear morphology and intensity, cell permeability, mitochondrial mass/ potential, F-actin and cytochrome c. In addition, treatment with an apoptosis-inducing concentration of panduratin A resulted in significant inhibition of Nuclear Factor-kappa Beta (NF-κB) translocation from cytoplasm to nuclei activated by tumor necrosis factoralpha (TNF-α), as illustrated by the HCS assay. Our study provides evidence for cell growth inhibition and induction of apoptosis by panduratin A in the A549 cell line, suggesting its therapeutic potential as an NF-κB inhibitor. © 2011.

Tiong S.H.,Sime Darby Technology Center | Looi C.Y.,University of Malaya | Arya A.,University of Malaya | Wong W.F.,University of Malaya | And 3 more authors.
Fitoterapia | Year: 2015

Abstract Vindogentianine, a new indole alkaloid together with six known alkaloids, vindoline, vindolidine, vindolicine, vindolinine, perivine and serpentine were isolated from leaf extract (DA) of Catharanthus roseus (L.) G. Don. Their structures were elucidated by spectroscopic methods; NMR, MS, UV and IR. Vindogentianine is a dimer containing a vindoline moiety coupled to a gentianine moiety. After 24 h incubation, vindogentianine exhibited no cytotoxic effect in C2C12 mouse myoblast and β-TC6 mouse pancreatic cells (IC50 > 50 μg/mL). Real-time cell proliferation monitoring also indicated vindogentianine had little or no effect on C2C12 mouse myoblast cell growth at the highest dose tested (200 μg/mL), without inducing cell death. Vindogentianine exhibited potential hypoglycemic activity in β-TC6 and C2C12 cells by inducing higher glucose uptake and significant in vitro PTP-1B inhibition. However, in vitro α-amylase and α-glucosidase inhibition assay showed low inhibition under treatment of vindogentianine. This suggests that hypoglycemic activity of vindogentianine may be due to the enhancement of glucose uptake and PTP-1B inhibition, implying its therapeutic potential against type 2 diabetes. © 2015 Elsevier B.V. All rights reserved.

Lim J.L.,National University of Malaysia | Lim J.L.,Sime Darby Technology Center | Bakar F.D.A.,National University of Malaysia | Yusof H.M.,Sime Darby Technology Center | Murad A.M.A.,National University of Malaysia
African Journal of Biotechnology | Year: 2012

Trichoderma species are among the primary producers of β-mannanase, an enzyme that catalyses the hydrolysis of β-1, 4-glycosidic linkages in mannans and heteromannans. In this study, a Trichoderma species producing high mannanase activity was identified as Trichoderma longibrachiatum based on sequence analysis of its rDNA internal transcribed spacer region. The open reading frame of the gene encoding for β-mannanase of T. longibrachiatum, man1 is 1,441 bp and is separated by two introns. The MAN1 amino acid sequence showed 95% identity to Trichoderma reesei β-mannanase. Domain analysis classified MAN1 as a member of glycosyl hydrolase family 5 and detected the presence of a carbohydrate-binding domain family 1 at its C-terminus. The recombinant mannanase, rMAN1, was successfully expressed as a ~60 kDa extracellular recombinant protein in Pichia pastoris and was verified via western blotting analyses. The specific activity of the purified rMAN1 was 1416.18 U/mg. The optimal rMAN1 activity was recorded at 55°C and pH 5. The enzyme was stable with 30 min preincubation at temperatures ranging from 4 to 50°C. The enzyme was stable at pH 4 to 7 but became progressively unstable at pH values below 3 and above 8. rMAN1 had a high affinity towards locust bean gum as a substrate, with a K m value of 0.95 mg/ml. © 2012 Academic Journals.

Discover hidden collaborations