Improvement of the method for isolating cholesterol from animal brain tissue

Аннотация

Cholesterol and its derivatives are used in the production of liquid crystals, in pharmacology as a component of dosage forms and diagnostic tools, as a precursor to steroid drugs. Cholesterol in the composition of the cell plasma membrane plays the role of a bilayer modifier, giving it a certain stiffness due to an increase in the density of the "packing" of phospholipid molecules. In this work, an improvement is made in the technology for producing cholesterol from biological material. Keywords: phosphosolipids, cholesterol, drugs. 84 Scientific research results in pandemic conditions (COVID-19) When using cholesterol as a component of some diagnostic kits, the absence of phospholipid impurities in the preparation plays an important role. In the proposed method, the purity of the cholesterol obtained is achieved by treating cholesterol with aluminum oxide, which irreversibly sorb all anionic impurities. Bull brains were ground in a blender in the presence of ethanol in a ratio of 1: 2.5 and filtered. The resulting pasty mass was distributed in a thin layer on a plastic film and dried for several days. The dry product was pulverized and repeatedly (4-5 times) was extracted with acetone. The collected and combined extracts were evaporated to 500 ml and stored in a cold place. The precipitate formed was filtered off, suspended in a 5% solution of sodium hydroxide in alcohol and refluxed. The resulting precipitate was washed with 80% alcohol and dissolved in 2-3 volumes of acetone. The resulting mixture was applied onto an alumina column, eluting with acetone, periodically checking the effluent for the presence of cholesterol by thin layer chromatography (TLC). Fractions containing cholesterol were combined and evaporated. The solution was stored in a refrigerator at ‒ 40°C to form a precipitate containing cholesterol, the next day it was filtered off and dried in air. The resulting product was checked by TLC in the presence of a standard sample in the hexane-ethyl acetate system (3:1). Melting point - 148°C. It is determined that the improvement of the extraction technology preserves the qualitative characteristics of the obtained material, which can be used as a component for the production of dosage forms and diagnostic tools. Khujakulov Siyovush, PhD in Law, associate professor, doctoral student of the faculty of postgraduate education of the Academy of the Ministry of Internal Affairs of the Republic of Uzbekistan, Tashkent THE NECESSITY OF SYSTEMATIZATION OF NORMATIVE DOCUMENTS ON THE PREVENTION OF CRIME Khujakulov S. В. Abstract: the article substantiates the need to systematize normative documents on the prevention of offenses, based on the results of the analysis of scientific views of legal scientists, the practice of prevention of offenses and normative documents. Scientific conclusions and proposals for improving national legislation aimed at developing scientific and theoretical approaches to these issues have been developed. Scientific conclusions were made about 85