Obtaining Of β-Lactoglobulin By Gel Filtration Of Cow Milk Whey

Milk whey proteins carry out a number of important biological functions and also they are precursors of many biologically active peptides (antihypertensive peptides, antagonists of opioid receptors, regulators of intestinal motility, immunomodulatory, anti-microbial and anti-cancer peptides, appetite regulators and so on.). An important stage in natural bioactive peptides obtaining from milk whey proteins is the isolation of homogeneous proteins-precursors. Considering the significant difference in the molecular masses of whey proteins, a promising method for their selection is gel filtration. The purpose of the research was the fractionation of bioactive peptides precursors from milk whey using gel filtration on Sephadex G-150. The whey was obtained from fresh skimmed milk after isoelectric precipitation of casein. Gel filtration was carried out on the columns from a liquid chromatography kit by the “Reanal” company. The fractional composition and the degree of homogeneity of milk whey proteins were determined by disc-electrophoresis in the plates of a polyacrylamide gel. A repeated gel filtration of fractions from the chromatographic peaks, separated into sections, was performed to increase the fractionation efficiency. While choosing a dextran gel for gel filtration of precursors of biologically active peptides from milk whey proteins, we have taken into account the range of their molecular weights (from 10000 to 150000 Da), the ability to form supramolecular structures (β-LG), as well as the previously obtained results of gel filtration. As a result, it was shown that repeated gel filtration of milk whey on Sephadex G-150 allows efficiently fractionate the proteins-precursors of bioactive peptides. The range of peptides and proteins molecular weights that can be fractionated on this Sephadex is from 5000 to 300 000 Da. The usage of repeated gel filtration on Sephadex G-150 with the chromatogram separation into sectors allows to effectively fractionate proteins-precursors of bioactive peptides from milk whey. In particular, homogeneous β-lactoglobulin (degree of homogeneity > 95 %) and partially purified α-lactalbumin, as well as a group of immunoglobulins and a proteose-peptone fraction were obtained

The usage of CaCl2 gradient for isolation of αS2-caseins fractions

Запропоновано метод виділення αS2¬¬-казеїну з коров’ячого молока з використанням іонообмінної хроматографії на ДЕАЕ-целюлозі в об’ємі. В порівнянні з традиційними способами фракціонування білків казеїнового комплексу метод має низку переваг. Він простий у виконанні і не потребує великих затрат часу. Вихід електрофоретично чистої фракції αS2¬¬-казеїну складає близько 70 %.Method of obtains αS2-caseins from cow milk with the help of batch fraction on DEAE-cellulose have been proposed. The method has some preferences compared with the traditional approaches of the fractionation of casein protein complex. It is simple and quick in use. The recovery of electrophoretically pure was 70 %

Isolation and characterization of peptides from blood serum of patients with multiple sclerosis

In order to find novel molecular markers of multiple sclerosis we developed a scheme of oligopeptides’ isolation including their extraction from blood serum with 10 % trichloroacetic acid, followed by precipitation of soluble substances with acetone in ratio 6:1. Oligopeptides were dissolved in water and their characteristics was determined by gel filtration under HPLC conditions and thin layer chromatography. Obtained data have shown that blood serum of MS patients contains two oligopolypeptides with average molecular masses of 300–500 Da. We also studied biological activity of TCA-soluble peptides toward some eukaryotic and prokaryotic cells in comparison with phosphopeptides isolated from casein hydrolysates. It was found that TCA-soluble peptides are capable of effective inhibiting HeLa cells’ proliferation, while their inhibitory effect was expressed toward Jurkat T-cells and was not detectable toward U373 cells. The casein’s phosphopeptides were capable to stimulate proliferation of Jurkat cells and effectively inhibited growth of cells. Neither antibacterial, nor antifungal activities of these oligopeptides were detected