E. Vamanu


STUDIES CONCERNING THE OBTAINING OF BIOMASS FROM LACTOBACILLUS PARACASEI SSP. PARACASEI USING CORN EXTRACT AS NITROGEN SOURCE

E. Vamanu, A. Vamanu, Diana Pelinescu, O. Popa, Sultana Nita, Despina A. Ionescu, Narcisa Babeanu

Abstract
The modern zootechnics characterised by keeping the animals in unnatural conditions (high density, industrial feeding, chicken separation and stress) is not favourable for the animals. It results production problems with high economic risk by decreasing the zootechnic performances (low weight gain and high consumption index) and health alterations (intestinal disorders, diarrhea, infections). Thus, the purpose of this study consists in proving that the Lactobacillus paracasei ssp. paracasei BS6 strain has a similar productivity to the MRS medium. So as to perform the tests, a medium containing 2% glucose, 50% corn extract - 1% d.s., 1% Ca(OH)2 was used. This medium was chosen because corn extract is a natural raw material often used in the biosynthesis processes in drug industry. Corn extract is a subproduct resulted from corn processing for starch and sugar obtaining. It represents one of the most complex nutritive substrata for microorganisms development and a well-balanced source of nitrogen, carbon, sulfur and mineral salts. Three batch fermentations were realised. Glucose consumption, lactic acid accumulation, viability, maximum growth speed (μmax), duplication time (TD), productivity (P) were determined. The results analysis proved that the development of Lactobacillus paracasei ssp. paracasei strain is similar to that of the MRS medium.

Key words: Lactobacillus paracasei, glucose, productivity, fermentation