Removal of Ochratoxin A in Saccharomyces cerevisiae Liquid Cultures
Abstract
The capacity for removal of ochratoxin A (OTA) during alcoholic fermentation was evaluated in batch systems withone commercial strain and one wild strain of Saccharomyces cerevisiae. Batch alcoholic fermentations were carried
out in yeast extract-malt extract broth (YM) medium, with 18.0% glucose and OTA added to final concentrations
of 3.48 and 4.95 ng/mL respectively. The removal capacity of each yeast strain was examined after completion of
fermentation in batch culture and after extended contact with yeast biomass. The removal capacity of the yeast
strains was also examined in stationary phase cultures. Stationary phase yeasts were studied with biomass harvested
from the stationary phase of anaerobic fermentation, by incubation in phosphate buffer, with the addition of 5.00 ng/
mL of OTA. Removal studies with stationary phase cells were performed with viable and non-viable cells inactivated
with Na-azide. The study showed that in growing phase cultures, OTA removal was significant only after extended
contact with yeast biomass; up to 29.7% and 25.4% for wild yeast ZIM 1927 and commercial yeast Lalvin EC-1118
respectively, but not during alcoholic fermentation. In stationary phase cultures, viable and non-viable cells were
not significantly different in OTA removal from the medium. This demonstrated that OTA was not metabolised, but
possibly adsorbed by the yeast cells. The presence of OTA in synthetic media influenced yeast metabolism, causing
the production of higher volatile acidity by 0.08 and 0.13 g/L for Lalvin EC-1118 and ZIM 1927 respectively, and
lower concentrations of reducing sugar, by 0.32 g/L, but only for ZIM 1927.
Downloads
A copyright form will be e-mailed to the corresponding author when the manuscript has been accepted for publication.
In principle, the Author agrees to the following when he/she signes the copyright agreement:
I hereby assign to the SOUTH AFRICAN SOCIETY FOR ENOLOGY AND VITICULTURE (SASEV) the copyright of the text, tables, figures, supplementary material, illustrations and other information (the Material) submitted with the manuscript to be published in SOUTH AFRICAN JOURNAL OF ENOLOGY AND VITICULTURE (SAJEV) (the "Article"). The copyright becomes effective from the date the Article has been accepted for publication in SAJEV.
This is an open access journal, and the authors and journal should be properly acknowledged, when works are cited.
Author's may use the publishers version for teaching purposes, in books, theses, dissertations, conferences and conference papers.
A copy of the authors' publishers version may also be hosted on the following websites:
- Non-commercial personal webpage or blog.
- Institutional webpage.
- Authors Institutional Repository.
The following notice should accompany such a posting on the website: This is an electronic version of an article published in SAJEV, Volume XXX, number XXX, pages XXX - XXX, DOI. Authors should also supply a hyperlink to the original paper or indicate where the original paper (www.journals.ac.za/index.php/sajev/) may be found.
Authors publishers version, affiliated with the Stellenbosch University will be automatically deposited in the University's Institutional Repository SUNScholar.
Articles as a whole, may not be re-published with another journal.
The following license applies:
Attribution CC BY-NC-ND 4.0