DEVELOPING THE TECHNOLOGY FOR PRODUCING WATER-SOLUBLE MELANIN FROM THE WASTE OF PLANT RAW MATERIALS AND STUDYING ITS PHYSICOCHEMICAL PROPERTIES

Abstract

Recently, an increased attention to the use of natural pigments in various areas of industry is observed. From this viewpoint, the production of melanins from plant waste is of great interest. In the work, the waste of winery production – grape squeezes, as well as squeezers of seeds, chestnut shells, etc were used as a raw material.

The identification of the resulting pigment was carried out by spectroscopic methods. Heat treatment established that the amorphous precipitate of melanin was stable at temperatures up to 120 ° C, and the acid resistance of the obtained melanin solution was in the range of pH> 4.0. By gel filtration, electrophoresis and high performance liquid chromatography (HPLC), it was found that the obtained pigment contained four fractions. Their molecular weights and the amount in the amorphous precipitate were determined. Qualitative reactions and spectroscopic methods have shown that those reactions were similar to typical melanins. The elemental composition of the obtained melanin and its antioxidant properties were determined. The amino acid composition of melanin protein and the degree of solubility were determined.

Based on the physicochemical properties of the resulting melanin, it has been shown that it can be used as an efficient natural food coloring and plant growth stimulant, as well as an antioxidant.