The effect of Saccharomyces cerevisiae on the stability of the herbicide glyphosate during bread leavening

Abstract

Aims: To investigate the ability of baker's yeast (Saccharomyces cerevisiae) to degrade the herbicide glyphosate during the fermentation cycle of the breadmaking process. Methods and Results: Aqueous glyphosate was added to bread ingredients and kneaded by commercially available breadmaking equipment into dough cultures. Cultures were incubated in the breadmaker throughout the fermentation cycle. The recovery of glyphosate levels following fermentation was determined, thus allowing an estimation of glyphosate degradation by yeast. Conclusions: It was shown, for the first time, that S. cerevisiae plays a role in metabolizing glyphosate during the fermentation stages of breadmaking. Approximately 21% was degraded within 1 h. Significance and Impact of the Study: As a result of projected increases in the glyphosate use on wheat and the role of bread as a dietary staple, this may contribute to more informed decisions being made relating to the use of glyphosate on glyphosate-resistant wheat, from a public health/regulatory perspective.

Saccharomyces Cerevisiae as a Tool to Evaluate the Effects of Herbicides on Eukaryotic Life

“…The finding that the herbicide S, differently from its pure AI G, had clear negative effects on K310 was in accordance with findings by Low and colleagues. They reported that bakers' yeast can metabolize up to 20% of G during the bread making process, probably with detoxification mechanisms which can result in the production of new degradation compounds, whose action is still unknown (Low et al, 2005). Additionally, our finding is also in good agreement with a consistent number of reports indicating that commercial formulations containing G are much more toxic than G alone in several organisms/cells (dos Tsui & Chu, 2003;Peixoto, 2005;Benedetti et al, 2004).…”

Wheat preharvest herbicide application, whole‐grain flour properties, yeast activity and the degradation of glyphosate in bread

“…Contrary to data reported by Low et al . (), our results also suggest that dough fermentation would not be an effective technique to degrade glyphosate residues in wheat.…”

“…According to Low et al . (), yeast would metabolise about 20% of pure glyphosate in dough fermented for only 1 h. To our knowledge, no scientific evidence has been reported on the effect of commercial glyphosate preparation on baker's yeast fermentative activity. Little information is also available on the impact of yeast fermentation and bread baking on the degradation of glyphosate.…”

“…Compared to pure glyphosate, commercial preparations of Roundup Ò may contain as much as 20% surfactants and would have higher inhibitory potential on wine yeast and dairy starters (Braconi et al, 2006;Clair et al, 2012). According to Low et al (2005), yeast would metabolise about 20% of pure glyphosate in dough fermented for only 1 h. To our knowledge, no scientific evidence has been reported on the effect of commercial glyphosate preparation on baker's yeast fermentative activity. Little information is also available on the impact of yeast fermentation and bread baking on the degradation of glyphosate.…”

A Saccharomyces cerevisiae-based bioassay for assessing pesticide toxicity

“…For instance, the presence of four fungicide residues (cyprodinil, fludioxinil, glyphosate, and pyrimethanil) during fermentation affected the aromatic composition of Vitis vinifera white wines inoculated with S. cerevisiae strains, causing a decrease in organoleptic quality [12][13][14]. Also, analysis of the S. cerevisiae gene expression pattern in response to lindane (an organochlorine pesticide) revealed mitochondrial dysfunction, oxidative stress, and ionic homeostasis [15,16].…”