Biotechnologia Acta

5-18

Authors: O. M. Klyuchko

Kavetsky Institute of Experimental Pathology, Oncology and Radiobiology of the National Academy of Sciences of Ukraine, Kyiv The goal of publication was the analysis of cluster methods and possibility of their application in biotechnology. The evidences found in scientific literature were summarized and analyzed. This article gives a brief description of cluster analysis — basic principles, some examples of their application are given for biotechnological problems. Results of the biotechnological studies that required application of cluster methods in combination with other mathematical approaches are considered. The conclusion contains an evaluation of the performed analysis as well as recommendations on the application of cluster analysis methods in biotechnology.

30-35

Authors: L.P. Dragan, A.I. Mruk, V.M. Golian, L.P. Buchatsky

The purpose of the work was to reproduce the sterlet of the Danube and Dnieper populations using cryopreserved sperm frozen in modified cryoprotective medium. Low-temperature cryopreservation of sterlet male reproductive cells was carried out in accordance with conventional procedures of cryobiology. As a result of the performed work, it has been found that the applied cryoprotective environment, which includes methanol, enhances the cryoprotective effect and is technologically optimal for the process of the Danube and Dnieper populations of sterlet sperm storage. Fish sperm cells retained viability after defrosting; their ability to fertilize the eggs was restored. The results of the conducted studies indicate that, despite a certain decrease in the quality properties of sperm after freezing/defrosting, its ability to fertilize did not significantly decrease. Revived in this way larvae from two populations of sterlet were used to reproduce repairing brood stock under conditions of fish farming. Such a method of sterlet sperm cryopreservation could be recommended for use at commercial enterprises with sturgeon fish commodity cultivation.

51-62

Authors: Turov V.V., Krupska T.V., Golovan А.P., Кartel М.Т.

The state of water in the hydrated sucrose powder, in its melt, and composite systems containing 3 parts of silica (A-300 or AM1) and 1 part of sucrose in air, low-polar organic solvent-deuterochloroform and CDCl3 medium with addition of strong acids has been studied by low-temperature 1H NMR spectroscopy. It was demonstrated that at the joint mechanoactivation of sucrose with nano-silica, its amorphization takes place. In this case, the adsorption of water in such a composite is not accompanied by the dissolution process in interfacial water of the sucrose immobilized on the SiO2 surface. It was found that the effect of sucrose solubility increasing accompanies the placement of the composite in a medium that does not dissolve water and sucrose, an organic solvent - deuterochloroform. It was suggested that it is due to an increase the contact area of adsorbed water clusters with the sucrose surface. The maximal concentration of sucrose, which dissolves in interfacial water, is about 30% by weight. The replacement of hydrophilic silica (A-300) by hydrophobic silica (AM1), while maintaining the concentration ratio of components and the amount of adsorbed water, reduces the free energy of water binding in the composite system. The obtained regularities can be used in the design of a new generation of enterosorbents.