99-10-5Relevant articles and documents
A chlorogenic acid esterase from a metagenomic library with unique substrate specificity and its application in caffeic and ferulic acid production from agricultural byproducts
Gui, Lun,Long, Qizhang,Yao, Jian
, (2021/08/25)
Soil microbes are an abundant source of enzymes with unique properties that may be useful for industrial applications. As most wild-type strains show low chlorogenic acid esterase expression and activity, and most microbes cannot be cultured in the laboratory, a metagenomic approach provides methods of identifying new enzymes. In this study, a gene encoding a chlorogenic acid esterase, named Tan410, was isolated from a soil metagenomic library and overexpressed in Escherichia coli BL21 (DE3). The recombinant enzyme, with a predicted molecular weight of 54.88 kDa, was purified to homogeneity. The K m and V max values for Tan410 were 1.26 mM and 0.33 mM min–1, respectively, with chlorogenic acid as the substrate. Its optimum temperature and pH for reaction were 30 °C and 7.5, respectively. The enzyme exhibited moderate thermostability and broad pH stability (3.0–10.0). Tan410 was also able to hydrolyse ethyl ferulate, methyl caffeate, propyl gallate, ethyl gallate, methyl vanillate, methyl benzoate, ethyl benzoate, methyl 2,5-dihydroxybenzoate, and methyl 3,5-dihydroxybenzoate, and it released caffeic and ferulic acids from agricultural byproducts (destarched wheat bran and coffee pulp). Tan140 has potential for industrial application in biomass valorization.
Synthesis method of 3,5-dimethoxybenzoic acid ethyl ester
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Paragraph 0004; 0006, (2017/01/17)
The invention discloses a synthesis method of 3,5-dimethoxybenzoic acid ethyl ester, and belongs to the field of chemosynthesis. According to the method, benzene is firstly used for producing resorcinol under specific conditions; under the condition of using dimethylformamide as a solvent by anhydrous potassium carbonate and carbon dioxide, the 3,5-dihydroxy-benzoic acid is finally obtained through impurity removal, decoloring, pH value regulation and cooling crystallization; then, the 3,5-dihydroxy-benzoic acid is mixed with dimethyl sulfate in a stirring condition; a sodium hydroxide solution is dropwise added into the materials for backflow; the pH value is regulated after the backflow; the pressure reduction filtering, washing and drying are carried out after cooling to 0 DEG C; the 3,5-dimethoxybenzoic acid is obtained; finally, the 3,5-dimethoxybenzoic acid is esterified with absolute ethyl alcohol under the condition of concentrated sulfuric acid; finally, the 3,5-dimethoxybenzoic acid ethyl ester is obtained.
Metal incorporated Horseradish Peroxidase (HRP) catalyzed oxidation of resveratrol: Selective dimerization or decomposition
Li, Chang,Xu, Xiaofei,Lu, Jing,Wang, Lin,Pan, Yuanjiang
, p. 22976 - 22980 (2013/11/19)
Horseradish Peroxidase (HRP) is a commercially available and prevalently used peroxidase with no specific substrate binding domain. However, after being incorporated with different metal cations, new catalytic functions were found in biomimetic oxidation of resveratrol. Based on the results of screening, Ca, Cu, Fe and Mn incorporated enzymes showed distinctive effects, either decomposition or dimerization products were observed.
