Characterisation and purification of a cinnamate esterase fromAspergillus niger industrial pectinase preparation
✍ Scribed by Barbe, Christine; Dubourdieu, Denis
- Publisher
- John Wiley and Sons
- Year
- 1998
- Tongue
- English
- Weight
- 158 KB
- Volume
- 78
- Category
- Article
- ISSN
- 0022-5142
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✦ Synopsis
Pectolytic enzymatic preparations used in enology come from Aspergillus niger. They have a desirable principal activity and several secondary activities. Among these secondary activities, three classes of esterases were detected : an esterase speciÐc for ester linkage between cinnamic acid and alcohol (cinnamate esterase) ; an esterase acting on ester linkage between two phenolic rings (depsidase) ; and an esterase hydrolysing ester linkage between phenolic acids and straight-chain alcohols (phenyl esterase). Only the Ðrst class of enzyme is able to hydrolyse the cinnamic acid tartrate ester of the white must. The authors tried to purify the cinnamate esterase from the other esterase of an A niger industrial pectolytic preparation. This puriÐcation was done in two steps. A gel Ðltration on S200 HR Sephacryl was Ðrst used. This step eluted two fractions : esterases and pectin esterase. The second step was affinity chromatography on a 4B Sepharose EAH grafted with chlorogenic acid. This step eluted two fractions : an unretained fraction containing the phenyl esterase and the depsidase ; and a retained fraction with the cinnamate esterase. This enzyme has a molecular weight of 240 kDa and contains two submits of 120 kDa. A new classiÐcation for these three esterases is suggested.
1998 Society of Chemical Industry.