BREWER’S SPENT YEAST AS A POTENTIAL STIMULATIVE AGENT IN RYE PLANTLETS

References: 17th International Multidisciplinary Scientific GeoConference SGEM 2017, www.sgemviennagreen.org, SGEM2017 Vienna GREEN Conference Proceedings, ISBN 978-619-7408-28-7 / ISSN 1314-2704, 27 - 29 November, 2017, Vol. 17, Issue 43, 27-34 pp; DOI: 10.5593/sgem2017H/43/S18.004

ABSTRACT

Brewer’s spent yeast is a byproduct containing high amounts of nitrogen, vitamins and immunogen compounds such as β-glucans. Several uses of spent yeast were described, but the phytostimmulatory potential was not previously tested. In the present paper, the effects of spent brewery yeast on rye microgreen growth and composition and the potential use as an elicitor is assessed. Rye microgreens elicited with spent yeast presented improved germination, especially after 4 days of cultivation. Increased plantlet length and fresh mass were recorded for 50% yeast treatment after 8 days of cultivation. Total phenolic contents were enhanced by 10 and 50% yeast treatment after 4 days of cultivation. Antioxidant activity of rye microgreens were higher than control plantlets at all yeast concentrations after 6 days of cultivation. In comparison, ascorbic acid increased the germination percentage at 1000 mg/l and lead to increased plantlet length and biomass at 100 and 500 mg/l after 8 days of cultivation. Total phenolic contents were stimulated after 8 days of cultivation by 1000 mg/l ascorbic acid.
Spent brewery yeast and ascorbic acid may be further investigated as eliciting agents for cultivating rye microgreens with improved growth and bioactive substances contents.

Keywords: Saccharomyces, Secale cereale L., germination, phenolic contents, elicitation