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Microbial milk-clotting enzymes are valued as calf rennet substitutes in the cheese industry. Mucor pusillus QM 436 was identified to produce the highest milkclotting activity during screening of 19 fungal strains. Salted whey resulting from Ras (Cephalotyre) cheese manufacture as a whole medium for growth of Mucor pusillus QM 436 and production of the enzyme. The milk-clotting enzyme from Mucor pusillus QM 436 was purified to 7.14-fold with 54.4% recovery by precipitation in ammonium sulfate, ethanol and fractionated by gel filtration on Sephadex G-100. The enzyme was active in the pH range 5.5-7.5 and was inactivated completely by heating 5 min at 70ºC and 30 min at 65ºC. The highest level of enzyme activity was obtained at 60ºC, pH 5.5. A positive and proportional relationship occurred in presence of CaCL2 in milk, with inhibition occurred in presence of NaCl. The high level of milk-clotting activity coupled with a low level of thermal stability suggested that the milk-clotting enzyme from Mucor pusillus QM 436 should be considered as a potential substitute for calf rennet.

The objective of this research was to determine whether whey, a by-product from a cheese manufacturing process, could be used as an animal Feed. Sheep were judged as a suitable alternate ruminant to carry out preliminary trials to allow scientific investigation of the suitability and the value of the whey. Also these trials were used to demonstrate to farmers the potential benefit of using whey in their feeding diets and to answer any preliminary concerns. Benefits and achievements results it could be concluded that for farms: Whey replaces 100% of water intake at the farm, Whey provides a low-cost alternative to liquid feeds, at a fraction of the cost (less than 10% of molasses), 19 liters of liquid whey permeate can replace the same amount of energy and protein as provided by 2.4 kg of a 88% crude protein feed mix/roughage, Roughage intake per kg gain can be reduced from 3kg to 1kg (75% weighing (200kg/head) being fattened to 400kg, an additional income of $30/head will be achieved, Whey can improve the feed palatability, texture, and dust control of feedlot rations. It provides a balanced nutrition of energy, protein, minerals, and a safety factor to compensate for poor or variable quality diets, being a pump able supplement, whey can save on feeding overheads as it requires less labour and feeding and mixing equipment, and can provide an economic and convenient method to feed urea supplements, vitamins, minerals and feed additives. For Dairy Factories:

Background. Rosemary (Rosmarinus offi cinalis L.) is a spice and medicinal herb widely used around the world of the natural antioxidants, and it has been widely accepted as one of the spices with the highest antioxidant activity. Transglutaminase (EC 2.3.2.13; TGase) is an enzyme capable of catalysing acyl transfer reactions by introducing covalent cross-links between proteins, as well as peptides and various primary amines. TGase activity in plants was fi rst observed in pea seedlings, and subsequently found in organs of both lower and higher plants. Recently, TGase has captured researchers' interest due to its attractive potential application in food industries. Therefore, the objectives of this study are isolation and purifi cation of TGase from new plant source rosemary (Rosmarinus offi cinalis L.) leaves at the laboratory scale. Moreover, investigation of the biochemical properties of the purifi ed TGase to provide a suitable TGase enzyme for food industry applications are in focus. Material and methods. Rosemary (Rosmarinus offi cinalis L.) leaves was used as a new plant source to TGase. The biochemical characteristics of the crude and purifi ed enzyme were determined. Results. Rosemary (Rosmarinus offi cinalis L.) TGase was purifi ed to homogeneity by successive three purifi cation steps including ammonium sulfate precipitatation, ion exchange chromatography on DEAE-Sephadex A-50 column and Size exclusion column chromatography on Sephadex G-100 column. Under experimental conditions, 20-30% of ammonium sulfate saturation in the enzyme solution had a high yield of enzyme activity could be obtained. The purifi ed enzyme from the Sephadex G-100 column had 21.35% yield with increased about 7.31 in purifi cation fold. Rosemary TGase exhibited optimum activity at pH 7.0 and 55°C for the catalytic reaction of hydroxylamine and Z-Gln-Gly. The purifi ed TGase almost maintained full activity after incubation for 15 min up to 60°C and it was completely inactivated at 85°C. The rosemary TGase was stimulated at 2-6 mM CaCl 2 concentrations while it lost about 5-20% from its activity by increasing CaCl 2 concentration. Sodium chloride (2-14%) shows no noticeable inhibition of the purifi ed TGase activity. Mg +2 , Ba +2 were acivited by the purifi ed TGase while it was strongly inhibited by Fe +2 , moderately by Cu +2 and Mn +2 . Conclusion. This paper reports on the purifi cation and characterisation of TGase from newly isolated plant, rosemary (Rosmarinus offi cinalis L.) leaves. Finding results of the TGase properties make this enzyme a good candidate for application in the food industry. However, additional work is required to increase activity yield during extraction and purifi cation for commercial scale of TGase from this plant.

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