INVESTIGADORES
MOZZI Fernanda Beatriz
congresos y reuniones científicas
Título:
Beta-lactoglobulin hydrolysis by Lactobacillus delbrueckii subsp. bulgaricus CRL 656 reduces its allergenicity
Autor/es:
M. PESCUMA; E. M. HÉBERT; M. DALGALARRONDO; J C GAUDIN; F. MOZZI; J M CHOBERT; G FONT DE VALDEZ
Reunión:
Congreso; V Congreso Argentino de Microbiología General (SAMIGE); 2008
Resumen:
The main whey protein, β-lactoglobulin (BLG), is responsible for
producing allergy, especially in children less than three years old. Whey
protein concentrates are commonly used to enhance protein content as well as to
replace fat in several foods (dairy and bakery products) being a potential risk
for patients allergic to milk proteins. Proteolysis is a common method to
reduce protein allergenicity. Lactic acid bacteria are well known for their
ability to degrade milk proteins. The aim of this work was to evaluate the
capacity of Lactobacillus delbrueckii subsp. bulgaricus
CRL 656 to specifically hydrolyze the BLG epitopes (41-60, 102-124, 149-162) thus
decreasing its recognition by IgE of allergic patients. β-Lactoglobulin was hydrolyzed using non-proliferating cells
incubated at 37°C during 8 h. Bovine BLG degradation was analyzed by Tricine
SDS-PAGE and RP-HPLC. Peptides released were identified by LC-MS/MS and the
hydrolyzates were assayed for their capacity to inhibit the BLG binding by using
a competitive ELISA Test. The results showed that L. delbrueckii subsp. bulgaricus
CRL 656 was able to degrade 32% of BLG after 8 h incubation and to release
mainly hydrophilic peptides. Ten peptides with molecular masses between 544.23
and 2541.11 Da were identified by LC-MS/MS. The sequence analysis of these
peptides indicated that this strain was able to degrade the main epitopes of
BLG. Seventy-one sera of young allergic patients to milk proteins were tested
for BLG-IgE recognition. Ten BLG-positive sera were selected for testing BLG
binding inhibition using the BLG hydrolyzates obtained from L. delbrueckii subsp. bulgaricus CRL 656. Eight patient-sera
did not recognize the BLG hydrolyzates and the remaining two showed low IgE
binding percentages (29.7-45.4%). These promising results indicate that L. delbrueckii subsp. bulgaricus CRL 656 could be used for
developing hypoallergenic dairy products.