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Secondary metabolites (Triterpenes) from Couroupita guianensis
Rokeya Begum,Mohammad S Rahman,A M Sarwaruddin Chowdhury,Choudhury M Hasan,Mohammad A Rashid 경희대학교 융합한의과학연구소 2009 Oriental Pharmacy and Experimental Medicine Vol.9 No.2
The n-hexane and carbon tetrachloride soluble fractions of a methanolic extract of the stem bark of the Couroupita guianensis furnished three compounds, identified as β-amyrin (1), betulin-3β- caffeate (2) and lupeol-3β-caffeate (3). The structures of the isolated compounds were deduced by extensive spectroscopic analysis as well as by comparison with published values. Compounds 1-3 were subjected to antioxidant screening through free radical scavenging activity by DPPH (1,1- diphenyl-2-picrylhydrazyl), where compound 2 showed moderate antioxidant activity with IC50 value 108.0 μg/ml. The n-hexane and carbon tetrachloride soluble fractions of a methanolic extract of the stem bark of the Couroupita guianensis furnished three compounds, identified as β-amyrin (1), betulin-3β- caffeate (2) and lupeol-3β-caffeate (3). The structures of the isolated compounds were deduced by extensive spectroscopic analysis as well as by comparison with published values. Compounds 1-3 were subjected to antioxidant screening through free radical scavenging activity by DPPH (1,1- diphenyl-2-picrylhydrazyl), where compound 2 showed moderate antioxidant activity with IC50 value 108.0 μg/ml.
Enhancement of antimicrobial properties of shoe lining leather using chitosan in leather finishing
Mahmud, Yead,Uddin, Nizam,Acter, Thamina,Uddin, Md. Minhaz,Chowdhury, A.M. Sarwaruddin,Bari, Md. Latiful,Mustafa, Ahmad Ismail,Shamsuddin, Sayed Md. Techno-Press 2020 Advances in materials research Vol.9 No.3
In this study, a chitosan based coating method was developed and applied on the shoe lining leather surface for evaluating its inhibition to bacterial and fungal attacks. At first, chitosan was prepared from raw prawn shells and then the prepared chitosan solution was applied onto the leather surface. Secondly, the characterization of the prepared chitosan and chitosan treated leather was performed by solubility test, ATR-FTIR, XRD pattern, SEM and TGA. Evaluation of antimicrobial efficacy of chitosan was assessed against two gram positive, two gram negative bacteria and a reputed fungi by agar diffusion test. The results of this study demonstrated that chitosan took place in both the surface of collagen fibres and inside the collagen matrix of crust leather. The chitosan showed strong antimicrobial activities against all the tested microorganisms and the inhibition increased with increasing percentage of chitosan. Therefore, the prepared chitosan in this study can be an environment friendly biocide, which functions simultaneously against different spoilage bacteria and fungi on the finished leather surface. Thus by using the prepared chitosan in shoe lining leather, the possibility of microbial attack during shoe wearing can be minimized which is one of the important hygienic requirements of footwear.
Secondary metabolites (Triterpenes) from Couroupita guianensis
Begum, Rokeya,Rahman, Mohammad S,Chowdhury, A M Sarwaruddin,Hasan, Choudhury M,Rashid, Mohammad A Kyung Hee Oriental Medicine Research Center 2009 Oriental pharmacy and experimental medicine Vol.9 No.2
The n-hexane and carbon tetrachloride soluble fractions of a methanolic extract of the stem bark of the Couroupita guianensis furnished three compounds, identified as $\beta$-amyrin (1), betulin-$3{\beta}$-caffeate (2) and lupeol-$3{\beta}$-caffeate (3). The structures of the isolated compounds were deduced by extensive spectroscopic analysis as well as by comparison with published values. Compounds 1-3 were subjected to antioxidant screening through free radical scavenging activity by DPPH (1,1-diphenyl-2-picrylhydrazyl), where compound 2 showed moderate antioxidant activity with $IC_{50}$ value $108.0{\mu}g/ml$.