Pectinex

Golden delicious apples Malus domestica) and tomatoes Solarium lycopersicum) were purchased at the local market. Fruits were peeled and sliced before treatment (4 h at 45 °C) with 0.1 % Pectinex Ultra Sp-L (Novo Ferment) in presence of 9 mM ascorbic acid. The insoluble material was then eliminated by centrifugation and the obtained juices dialysed against distilled water. 

SPS could be degraded by the cruder, aaikalus preparation Pectinex Ultra-SP, giving a product consisting mostly of the monomeric sugars xylose, galactose, fucose, arabinose and... 

RG-lyase was purified from Pectinex Ultra SP-L, produced by Aspergillus aculeatus, using anion- and cation-exchange chromatography. The purified RG-lyase differed from RG-hydrolase in pi and pH optimum and stability (Table I). 

Pectinex Ultra SPL (Novo Nordisk), endo-polygalacturonase (MegaZyme) and a partially purified polygalacturonase from Aspergillus niger(E i eiy and Ojamo 1990) were used. 

The cambium was isolated firom spruce (Picea abies) logs felled in October-November. The bark was stripped off, and the cambium was removed by gentle scraping. The isolated cambium was immediately fiozen in liquid nitrogen and fi-eeze-dried. The carbohydrate composition of the isolated cambium was analysed by HPLC after enzymatic hydrolysis using Pectinex Ultra and a mixture of cellulases and hemicellulases (Buchert et al 1993). 

Pretreatment of wood with pectinolytic enzymes facilitates the debarking. The energy consumption during debarking of spruce in a laboratory scale debarker is clearly decreased after treatment with Pectinex Ultra (Table 1). Several hours is needed for effective preteatment (Table 2). 

The effect of pretreatment time on the debarking of spruce. The enzyme was Pectinex Ultra., 185 nkat/ml. 

The effect of the partially purified polygalacturonase was low as compared to that of the commercial pectinase preparation, Pectinex Ultra, containing various side activities in addition to polygalacturonase (Table 3). 

Cellulose and complex pectic polysaccharides are the main matrix of the water-insoluble residue after centrifugation of fruit and vegetable homogenates. The use of pectinolytic enzymes is therefore necessary to solubilize the solid sample. Pectinolysis is known to degrade efficiently large pectic polysaccharides, but some of them, for example, rhamnogalacturonan-II, are considered to be resistant to pectinolytic enzymes [45]. A mixture of commercial products Rapi-dase LIQ and Pectinex Ultra-SPL , was reported for the release of metal-complexes from the solid parts of edible plants, fmits, and vegetables [45]. 

Pectinex Ultra SP-L is a commercial enzyme preparation from Aspergillus acu-leatus that is used in the food industry for reducing viscosity in fruit juice processing. It contains different pectinolytic and cellulolytic enzymes [29]. In addition, the existence of fructosyltransferase activity in Pectinex Ultra SP-L has been reported by several authors [30-32]. In recent years, we have investigated the purification, characterization, and application of the fructosyltransferase from A. aadeatus contained in this commercial preparation [33]. 

For the above reasons, the effect of pH and ionic shength on the immobihzation of the fructosyitransferase from A. aculeatus on Sepabeads EC-EP was studied. Although this enzyme constitutes only a minor percentage (0.4% w/w) of the total proteins present in Pectinex Ulha SP-L, the commercial preparation was used directly (without enzyme purification) in order to develop a simple process that could be easily scaleable in the industry. It was considered that, although the other proteins present in Pectinex Ulha SP-L could also be immobilized in Sepabeads EC-EP, they would not interfere in fructooligosaccharide synthesis experiments. 

In order to bind the enzyme to the support using different functional groups, the immobilization was performed at two pH values (5.5 and 9.0), adjusting the pH of commercial Pectinex Ultra SP-L with potassium phosphate or sodium carbonate, respectively. At pH 5.5, the reactive groups of the protein are the carboxylic... 

Based on the above results at low ionic strength, the direct immobilization of Pectinex Ultra SP-L, the pH of which is 4.8, on Sepabeads EC-EP was assayed... 

Figure 11.4 Effect of buffer concentration on the immobilization on Sepabeads EC-EP carriers of transfmctosylating activity in Pectinex Ultra SP-L. Immobilization conditions 30 mg of protein added per gram of support, 24h, room temperature, and roller shaking. Adapted from Ref [56].

Although fructosyl-transfer enzymes have been immobilized by different techniques such as adsorption [71], entrapment [72], or covalent attachment [73], the biocatalyst activity per mass unit is not commonly reported. However, Chiang et al. [74] described a maximum activity of 77 U/g for A. niger 5-fructofuranosidase covalently attached to methacrylamide-based polymeric beads. More recently, fruc-tosyltransferase from A. aculeatus present in Pectinex Ultra SP-L was covalently bound to Eupergjt C [75] although the activity recovery was high, the activity per gram of biocatalyst was not reported. 

Figure 11.5 Batch synthesis of fnictooligosaccharides catalyzed by immobilized Pectinex Ultra SP-L in Sepabeads EC-EPJ. (a) Product distribution and (b) total fhjctooligosaccharide. Experimental conditions 630g/l of sucrose, O.JU/ml (standard DNS assay), 50mM sodium acetate buffer (pH 5.4), and 60°C. Adapted from Ref. [56].

The fructosyltransferase mined from the commercial preparation Pectinex Ultra SP-L is quite stable towards pH, temperature, and the presence of chemicals. The A aculeatus fructosyltransferase showed a high transferase hydrolase raho that provides it with great potential for oligosaccharide synthesis. The enzyme can be easily immobilized on epoxy-activated supports for better performance. Further studies are required to draw mechanishc conclusions on the nature of the kinetics observed with this fructosyltransferase. 

In this work the effects of foiu enzymes and their combinations are examined. The enzymes are as follows A, lipase from Mucor miehei (Amano, lipase M, 10 mg) B, hemicellulase (Sigma, 10 mg) C, pectinase (Novo Nordisk, Pectinex 3XL, 20 iL) D, protease N (Amano, 10 mg). 

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.)...

Pectinesterase Origin rec. microorganism Novozymes Pectinex SMASH... 

Pectinex. [NovoNodisk] Pectinase pectin-decomposing enzymes for food, wine, and citrus processing. 

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