EXOGENOUS REGULATION OF PRODUCTIVITY OF PENICILLIUM CITRINUM – KERATINASE PRODUCER

Issue: 
9
Year: 
2016

Z.K. Nikitina
Dr.Sc. (Biol), Professor, All-Russian Scientific Institute of Medicinal and Aromatic Plants (Moscow)
E-mail: nikitinaz@yandex.ru
I.K. Gordonova
Ph.D. (Biol.), Leading Research Scientist, All-Russian Scientific Institute of Medicinal and Aromatic Plants (Moscow)

Keratin producers search is of undoubted interest for different fields of human activity. These enzymes are used in agriculture, leather and textile industry, medicine and cosmetology. In addition, the use of these hydrolases is promising for solving various environmental problems. It has been previously shown that micromycete Penicillium citrinum in submerged cultivation on media containing keratin, secreted proteolytic enzymes in the culture fluid. The aim of this work was the study of exogenous factors in the regulation of P. citrinum enzyme secretion to increase the micromycete productivity. Screening method with the definition of lysis zones, lysis index, sizes of colonies and its growth rate were used to assess hydrolytic activity of P. citrinum. Human hair, skin proteins and liquid keratin were used in surface and submerged cultivation. The diameters of the colonies and average growth rate declined in a number of liquid keratin > skin proteins > hair keratin. Micromycete lysis indexes were higher in the medium with hair keratin than on the medium with the skin proteins at all stages of cultivation. On the medium with liquid keratin the lysis zones were absent. This may indicate that the highest potential as the proteinases inducer for P. citrinum has hair keratin. The results of submerged cultivation have confirmed a higher degree of induction of the secretion of proteinases by hair keratin compared to skin proteins and liquid keratin.

Keywords: 
Key words: proteinases
keratin
Penicillium citrinum.