Bilberries (Vaccinium myrtillus) and blackcurrants (Ribes nigrum) were treated with extensive dosages of commercial cell wall degrading enzyme preparations, i.e. Econase CE, Pectinex Ultra SP-L, Pectinex Smash, Pectinex BE 3-L and Biopectinase CCM. The enzymes were dosed based on the polygalacturonase activity. The juice yield was improved in both berries as a result of the enzymatic treatment. The improvement was more pronounced with blackcurrants owing to their thicker cell walls. The impact of the enzymatic treatment on anthocyanins present in the juices was investigated using HPLC-DAD. The enzyme preparations affected the contents and composition of anthocyanins in the juices. Pectinex Ultra SP-L, Pectinex Smash, Pectinex BE 3-L and Biopectinase CCM increased the total content of anthocyanins by 13-41% in the bilberry juices and by 18-29% in the blackcurrant juices. Econase CE, however, produced a dramatic decrease in the total anthocyanin content in the bilberry juice due to its enzyme profile, whereas no such effect was observed with the blackcurrant juice. All the enzyme mixtures tested produced a total or extensive loss of anthocyanidin galactosides in bilberry juice. Commercial enzyme preparations used in the production of berry juices can improve extraction of anthocyanins into the juice. However, they may effectively hydrolyse certain glycosides and thus affect the profile of extracted anthocyanins.

Resolution of (R,S)-ibuprofen enantiomers by esterification in different organic solvents was studied using Candida cylindracea lipase. This enzyme preparation had high enantiospecificity for S(+)-ibuprofen in the esterification reaction of a racemic ibuprofen with primary alcohols. The esterification yields of secondary alcohols were much lower than those of primary alcohols. Esterification with tertiary alcohols was not observed. The synthesis of esters was profoundly affected by the amount of water in the reaction mixture. C. cylindracea lipase was active only in very hydrophobic solvents. The esterification activity of the lipase was reduced significantly by addition of water. The R- and S-enantiomers of ibuprofen were determined without derivatization by HPLC using a chiral column.

No abstract

Soy lecithin was modified by enzymatic transesterification in a solvent-free system. 1,3-Specific Rhizomucor miehei lipase was found to be efficient in the transesterification with lauric acid and oleic acid, where oleic acid was more incorporated into soy lecithin. Phospholipase A 2 incorporated lauric acid hardly at all, but it hydrolyzed lecithin efficiently. The mixture of lipase and phospholipase A 2 (1:1, w/w) incorporated lauric acid to the same extent as did 1,3-specific lipase alone at the same tota[ enzyme concentration. The main fatty acids replaced were palmitic and linoleic acids by 1,3-specific lipase and its mixture with phospholipase A2, and linoteic and linolenic acids by phospho[ipase A 2 alone, suggesting an improved oxidative stability of the resulting product. Hydrolysis could not be prevente.d, but it could be regulated by incubation time and by enzyme dosage. The rninimal water content for significant incorporation of lauric acid into lecithin was below 0.5% of the weight of the reaction mixture. ]AOCS 72, 1375-1379 (1995).

Lipophilic extractives commonly referred to as wood pitch or wood resin can have a negative impact on paper machine runnability and product quality. The lipophilic extractives are composed mainly of fatty acids, resin acids, sterols, steryl esters and triglycerides. In this work, the suitability of laccases for the modification of fatty and resin acids was studied, using two model fractions. In the treatments, resin and fatty acid dispersions were treated with two different laccases, i.e. laccases from Trametes hirsuta and T. villosa. Different chromatographic methods were used to elucidate the effects of laccase treatments on the chemistry of the fatty and resin acids. Both laccases were able to modify the fatty and resin acids to some extent. In the case of fatty acids, a decrease in the amount of linoleic, oleic and pinolenic acids was observed, whereas the modification of resin acids resulted in a reduced amount of conjugated resin acids.