Pectin enzyme degradation

If we compare liquefaction to maceration, more activities are needed to liquefy the cell wall. Since 1991, new pectinases activities such as rhamnogalacturonase, pectin acetylesterase and xyloglucanases complex have been found to be important in the apple liquefaction by Henck Schols, Jean-Paul Vincken and Voragen [3]. The cellulose-xyloglucan complex accounts approximatively 57% of the apple cell-wall matrix. In a liquefaction process, an efficient enzymic degradation of this complex is crucial to increase the sugars extraction, to decrease the viscosity of the pulp then to be able to ultra-filtrate the juice without second depectinisation, at last to have negative alcohol tests required by some concentrate customers. 

Figure 9. Gel filtration chromatography of the HCl-soluble apricot pectin fraction, degraded by various enzyme systems on a Sephacryl S—300 column (68 x 1.05 cm), eluent 0.05 M phosphate buffer pH 7. AGA is anhydrogalacturonic acid Pectinex is a wide-spectrum commercial pectinase. (Reproduced with permission from ref. 54. Copyright 1985.)...

Production of enzymes degrading plant cell walls has been studied using media containing cellobiose or ammonium ions as limiting nutrients. Pectin lyase was primarily cell-associated during exponential growth in batch culture but accumulated in the supernatant during the stationary phase. 

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