The increase of biodiesel production on the world and in Poland causes necessity to find out an effective way to collect obtained in technological process wasted which includes glycerin. The culture of biomass cells Candida utilis yeast strain growing in mediums with glycerin as main source of carbon gives a possibility to obtain fully worth feed protein (SCP). On the other hand feed yeasts as obligatory aerobes make with an easy way biotransformation of glycerin to dihydroxyacetone (DHA) –common compound during metabolism of yeasts and acetic acid bacteria. Used glycerin to the production of biomass fodder yeasts each time demands enzymatic step to transform these substrates by the influence of glycerin dehydrogenized to DHA. Based on these data it could be said that idea to use potential biochemist mixture of yeasts and acetic acid cultures could be more effective for utilization of glycerin from production of biodiesel than with a participation of monoculture yeasts type C. utilis. Obtained biomass of cell will keep criteria of worthily source of proteins as supplement to feeds.

Comparing the production of extracellular enzymes by the examined mutants Trichoderma reesei RUT-C30, Trichoderma reesei 18/14, Trichoderma reesei 18/15 under continuous cultivations in a medium containing undiluted whey with mineral salts fortifi- cation, it was found that the strain Trichoderma reesei 18/15 showed the highest FPU and xylanolytic activities with low proteolytic activity after continuous cultivation.

The antioxidative properties of hen egg phosvitin hydrolysate preparations were studied. Hydrolysis was performed using the bovine trypsin and protease from A. melleus. The progress and kinetics of the hydrolysis were analyzed by monitoring the degree of hydrolysis (DH), free amino group content and the RP-HPLC profiles of resulted peptides. The radical scavenging capacity on DPPH, ferric reducing activity (FRAP) and chelating activity on iron (II) were measured. The degrees of hydrolysis of final hydrolysates were 33,7% and 23,2% for protease from A. melleus and trypsin, respectively. The progress of reaction was also confirmed by determination of the free amino group content, which finally reached 3816 μM · g^-1 and 1198,5 μM · g^-1 for protease from A. melleus and trypsin. The twenty four-hour tryptic hydrolysate (0,27 μM Trolox · mg^-1) exhibited stronger scavenging activity on DPPH free radicals than that of protease from A. melleus (0,21 μM Trolox · mg-1). The hydrolysates exhibited also very strong chelating activity on iron (II). The hydrolysate with protease from A. melleus (24 -h) showed the highest level of this activity: 1466,3 μg Fe2+ · mg-1.