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

STUDII PRIVIND OBTINEREA BIOMASEI DIN LACTOBACILLUS PARACASEI SSP. PARACASEI UTILIZĀND EXTRACTUL DE PORUMB CA SURSA DE AZOT

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

Rezumat
Cresterea moderna a animalelor prin plasarea lor īn conditii nenaturale (densitate mare, alimentatie industriala, separarea puilor si stres) sunt defavorabile acestora. De aici decurg probleme de productie īn care riscurile majore de pierderi economice sunt legate de diminuarea performantelor zootehnice ale animalelor (cāstig scazut īn greutate si indice de consum mare) si alterarea starii generale de sanatate (dezordini intestinale, diaree, infectii). Studiul de fata, īsi doreste sa arate ca tulpina de Lactobacillus paracasei ssp. paracasei BS 6 are o productivitate cel putin similara cu cea calculata īn cazul mediului MRS. Pentru teste s-a folosit un mediu ce contine glucoza 2%, extract de porumb – 50% s.u. 1%, Ca(OH)2 1%. Alegerea mediului s-a facut datorita faptului ca extractul de porumb este o materie prima naturala foarte des īntrebuintata īn procesele de biosinteza din industria de medicamente. Extractul de porumb este un subprodus de la prelucrarea porumbului īn scopul obtinerii amidonului si a zaharului. El reprezinta unul din cele mai complexe substraturi nutritive pentru dezvoltarea microorganismelor, constituind sursa cea mai echilibrata de azot, carbon, sulf si saruri minerale. S-au efectuat 3 fermentatii īn sistem batch. S-a determinat consumul de glucoza, acumularea de acid lactic, s-a determinat viabilitatea si s-a calculat viteza de crestere maxima (μmax), timpul de dublare (TD), productivitatea (P). Analizānd rezultatele obtinute se poate constata ca dezvoltarea tulpinii de Lactobacillus paracasei ssp. paracasei BS 6 este comparabila cu cea de pe MRS.

Cuvinte cheie: Lactobacillus paracasei, glucoza, productivitate, fermentatie