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Bangi, Malaysia

Ahmad F.B.H.,University Putra Malaysia | Moghaddam M.G.,University Putra Malaysia | Basri M.,University Putra Malaysia | Abdul Rahman M.B.,University Putra Malaysia | Abdul Rahman M.B.,Malaysia Genomic Institute
Bioscience, Biotechnology and Biochemistry | Year: 2010

An easy and efficient strategy to prepare betulinic acid esters with various anhydrides was used by the enzymatic synthesis method. It involves lipase-catalyzed acylation of betulinic acid with anhydrides as acylating agents in organic solvent. Lipase from Candida antarctica immobilized on an acrylic resin (Novozym 435) was employed as a biocatalyst. Several 3-O-acyl-betulinic acid derivatives were successfully obtained by this procedure. The anticancer activity of betulinic acid and its 3-O-acylated derivatives were then evaluated in vitro against human lung carcinoma (A549) and human ovarian (CAOV3) cancer cell lines. 3-O-glutarylbetulinic acid, 3-O-acetyl-betulinic acid, and 3-O-succinyl-betulinic acid showed IC50 < 10 μg/ml against A549 cancer cell line tested and showed better cytotoxicity than betulinic acid. In an ovarian cancer cell line, all betulinic acid derivatives prepared showed weaker cytotoxicity than betulinic acid.

Ahmad F.B.H.,University Putra Malaysia | Moghaddam M.G.,University Putra Malaysia | Basri M.,University Putra Malaysia | Abdul Rahman M.B.,University Putra Malaysia | Abdul Rahman M.B.,Malaysia Genomic Institute
Biocatalysis and Biotransformation | Year: 2010

Immobilized Candida antarctica lipase, Novozym 435, was used to catalyze the esterification reaction between betulinic acid and phthalic anhydride to synthesize 3-O-phthalyl betulinic acid in n-hexane/chloroform. Response surface methodology based on a five-level, four-variable central composite rotatable design was employed to evaluate the effects of synthesis parameters such as reaction time, reaction temperature, enzyme amount and substrate molar ratio on the yield of ester. Based on the response surface model, the optimal enzymatic synthesis conditions were predicted to be: reaction time 20.3 h, reaction temperature 53.9°C, enzyme amount 145.6 mg, betulinic acid to phthalic anhydride molar ratio 1:1.11. The predicted yield was 65.8% and the actual yield was 64.7%. © 2010 Informa UK Ltd.

Monica H.H.L.,University Putra Malaysia | Patricia K.J.H.,University Putra Malaysia | Huat O.K.,University Putra Malaysia | Joseph B.C.F.,University Putra Malaysia | Muhammad M.N.,Malaysia Genomic Institute
Research Journal of Biotechnology | Year: 2016

Bacteria and enzymes in the gut of termites play an important role to digest lignocellulosic material. Coptotermes curvignathus is one of the very few destructive species that can infest living plants. In this study, five bacteria isolated from C. curvignathus gut; four aerobic Bacillus spp. and an anaerobic uncultured bacterium were identified to produce endoglucanase with molecular size of 11 kDa which is significantly smaller than the endoglucanase produced by Reticulitermes speratus. Biolog reader identification showed that TG117 and N45/1 were Bacillus cereus/thuringiensis, TG111 was Bacillus pseudomycoides and TG005 was Bacillus mycoides. Endoglucanase produced by aerobic isolate NA45/1 showed promising potential as an industrial enzyme with significantly higher enzymtic activity than the commercial cellulase from Aspergillus Niger (C1184 Sigma). Endoglucanase NA45/1 displayed enzymatic activity 0.3961 U at pH 9 and 45°C. The endoglucanase TG111 acted optimally at alkaline condition with 0.2294 U whereas endoglucanase TG117 functioned best at slightly acidic condition. This study showed that the termite gut has a wide range of endoglucanase enzymes with various optimum temperatures and pH.

Ahmad F.B.H.,University Putra Malaysia | Ghaffari M.,University Putra Malaysia | Ghaffari M.,Malaysia Genomic Institute | Basri M.,University Putra Malaysia | And 2 more authors.
Asian Journal of Chemistry | Year: 2010

In this paper, the spectroscopic data of the 3-O-acetyl betulinic acid is reported. This compound was prepared by enzymatic reaction of betulinic acid and acetic anhydride in the presence of lipase from Candida antarctica (Novozem® 435) at 54oC for 20 h in 79.3 % yield.

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