Antifungal Activity against Aspergillus parasiticus of Supernatants from Whey Permeates Fermented with Kefir Grains

GAMBA RAUL RICARDO; NI COLO CAROLINA ; CORREA FRANCO MARIANA; ANDREA ASTORECA ; TERESA ALCONADA; GRACIELA DE ANTONI; ANGELA LEON PELAEZ

advances in microbiology

Scientific Research Publishing Inc.

Año: 2015 vol. 5 p. 479 - 492

2165-3402

Aspergillus parasiticus, a common fungal contaminant in food and feed produces aflatoxin B1, which is classified as a human carcinogen. Kefir is an ancient fermented beverage obtained by the fermentation of different substrates with kefir grains. A very important waste produced by the dairy cheese industry is the permeate whey, which nowadays is a strong ambient contaminant. Our objective was the study of the antifungal effect of whey permeates fermented with kefir grains on i) A. parasiticus growth, ii) AFB1 synthesis and iii) the cellular damage produced by AFB1 on HepG2 cellular line. First, we studied the anticytotoxic and antifungal effect of the total kefir microorganisms and the cell free supernatants (CFS), respectively both obtained from the fermented product? and compared these results with those obtained with pure organic acids. Fungal inhibition was obtained with lower concentration of total undissociated acids with CFS (with 34.08 mM) than with organic acids (48.83 mM) in the culture medium. We also assessed that sub lethal doses of CFS and organic acids produce an increase in the mycotoxins synthesis in solid culture medium. Finally, we found that kefir microorganisms protect HepG2 cell line from the damage produced by the presence of aflatoxin B1.