Proteolysis of leaf proteins by endogenous leaf proteases between the time of harvest and the early stages of processing accounts for substantial losses (up to 40%) in recoverable protein from Medicago sativa [lucerne (alfalfa)] leaves. To study this problem, the proteolytic enzymes from A{. sativa were partially purified by ammonium sulphate fractionation and gel filtration. Carboxypeptidase, aminopeptidase and total protease activities were measured. Addition of the herbicide simazine to leaf extract inhibited the aminopeptidase and total protease activity, but had no effect on the carboxypeptidase activity. The extent of proteolysis in leaf extracts was found to be dependent on pH, temperature and time of handling and it was concluded that these factors were the most effective means of controlling proteolytic activity.

Acetone precipitates from culture filtrates of three isolates of Botrytis cinerea were resolved by isoelectric focusing on polyacrylamide gels to detect differences in the polygalacturonase and protein patterns. Only a few bands -four in the protein patterns and two in the polygalacturonase patterns -were common to all the isolates. Differences were also detected in polygalacturonase and protein patterns of the same isolate at different ages of culture (7, 14 and 2 1 d). Identical polygalacturonase patterns were obtained when isoelectric focusing was applied to an acetone precipitate either directly or after further purification by ion-exchange chromatography.

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Low-molecular weight peptide fractions were prepared from soya bean, lucerne (alfalfa) leaf protein, and wild grass leaf protein by enzymatic hydrolysis. The concentrated hydrolysates were used as substrates for plastein synthesis with a-chymotrypsin immobilised on chitin. When submitted to gel filtration on Sephadex G-50, the plasteins formed with the immobilised a-chymotrypsin were comparable to the plasteins formed from the soluble enzyme. lsoelectric focusing of the plasteins showed five bands each from immobilised a-chymotrypsin and from soluble chymotrypsin. However, slight differences in the isoelectric points of the comparable bands were observed .

23] Foti, M., M. Piatelli, M. T. Baratta, and G. Ruberto, Flavonoids, Coumarins, and Cinnamic Acids as Antioxidants in a Micellar claimed to have a positive effect on the quality of milk and milk products [1, 2].Lipase catalyzed transesterification is an efficient and cost-effective method for modifying fats for industrial purposes. The mild reaction conditions and the specificity of enzyme action result in products requiring few, if any, subsequent purification processes [3][4][5][6][7]. When a 1,3 specific lipase is used as a catalyst, there are fewer regioisomers than with chemical synthesis or unspecific lipases [8,9].The aim of this study was to investigate the possibility of using transesterification at different reaction times with a