CERELA   05438
CENTRO DE REFERENCIA PARA LACTOBACILOS
Unidad Ejecutora - UE
artículos
Título:
Hydrolysis of whey proteins by Lactobacillus acidophilus, Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus grown in a chemically defined medium.
Autor/es:
PESCUMA, M.; HEBERT, E.M.; MOZZI, F.; FONT DE VALDEZ, G.
Revista:
JOURNAL OF APPLIED MICROBIOLOGY
Editorial:
Blackwell Publishing
Referencias:
Año: 2007 vol. 103 p. 1738 - 1738
ISSN:
1364-5072
Resumen:
Aims: To evaluate the ability of themophilic lactic acid bacteria (LAB) to hydrolyse the whey proteins b-lactoglobulin (BLG) and a-lactalbumin (ALA) in a chemically defined medium (CDM). Methods and Results: The ability of three LAB strains to hydrolyse BLG and ALA was studied in a CDM supplemented with these proteins or whey protein concentrate (WPC). Protein hydrolysis was determined by Tricine- SDS–PAGE and RP–HPLC. Maximum BLG (21%) and ALA (26%) degradation by LAB was observed using WPC. Under starving conditions, BLG degradation was greater for Lactobacillus delbrueckii ssp. bulgaricus CRL 454 than for Lactobacillus acidophilus CRL 636 and Streptococcus thermophilus CRL 804. All three strains showed different peptide profiles and were not able to hydrolyse ALA under starvation.The ability of three LAB strains to hydrolyse BLG and ALA was studied in a CDM supplemented with these proteins or whey protein concentrate (WPC). Protein hydrolysis was determined by Tricine ⁄ SDS–PAGE and RP–HPLC. Maximum BLG (21%) and ALA (26%) degradation by LAB was observed using WPC. Under starving conditions, BLG degradation was greater for Lactobacillus delbrueckii ssp. bulgaricus CRL 454 than for Lactobacillus acidophilus CRL 636 and Streptococcus thermophilus CRL 804. All three strains showed different peptide profiles and were not able to hydrolyse ALA under starvation. Conclusions: The assayed LAB strains were able to degrade BLG during growth in a CDM and under starving conditions. The different peptide profiles obtained indicate distinct protease specificities. Significance and Impact of the Study: These strains could be used as adjunct cultures to increase BLG digestibility in whey-based or whey-containing foods. To our knowledge, this is the first report on the ability of a Lact. acidophilus strain to degrade BLG.