TITLE:
Antifungal Activity against Aspergillus parasiticus of Supernatants from Whey Permeates Fermented with Kefir Grains
AUTHORS:
Raúl Ricardo Gamba, Carolina Ni Colo, Mariana Correa, Andrea Astoreca, Teresa Alconada, Graciela De Antoni, Angela León Peláez
KEYWORDS:
Aspergillus parasiticus, Whey Permeate, Aflatoxin B1, Kefir Supernatants, Lactic Acid, Acetic Acid, Cytotoxicity, HepG2 Cells
JOURNAL NAME:
Advances in Microbiology,
Vol.5 No.6,
June
29,
2015
ABSTRACT: Aspergillus parasiticus, a common fungal contaminant
in food, produces aflatoxin B1, which is classified as 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 whey permeate, which nowadays is a strong ambient contaminant. The
aim of this work was to assess the effect of whey permeates fermented with kefir
grains against A. parasiticus growth,
aflatoxin B1 biosynthesis, and the kefir microorganisms protection against
the cell damage produced by aflatoxin B1. It was observed that kefir-cell-free-supernatants
(CFS) produced fungal inhibition. A fungicidal effect was observed with 65% v/v
of CFS in the culture medium (final pH 4.55 and total undissociated lactic and acetic
acid concentration 34.08 mM). Under these conditions, aflatoxin production was not
detected. Finally, it was found that non-viable kefir microorganisms protected HepG2
cells from the damage produced by aflatoxin B1.