Abstract:

Single factor experiments and an orthogonal array design L9(34) were used in combination to optimize process
parameters for the extraction of mannan from the autolyzed cell wall of waste wine yeast. Antioxidant activities of the
extracted mannan were also measured in this study. The results showed that under the optimum conditions: 1:17.5 (g/mL),
3%, 1.5 h and 100 ℃ for solid-to-liquid ratio, KOH concentration, extraction time and extraction temperature, respectively,
the extraction yield of mannan was 18.37%. The mannan from wine yeast displayed excellent antioxidant activities
with half maximal effective concentration (EC50) values of 1.156, 1.550, 9.724, 2.387 and 0.669 mg/mL for scavenging
2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+), hydroxyl, 2,2-diphenyl-1-picrylhydrazyl (DPPH),
superoxide anion radicals and chelating Fe2+, respectively.

Key words: waste wine yeast, mannan, extraction yield, antioxidant activities