Production and analysis of metabolites from solid-state fermentation of Chenopodium formosanum (Djulis) sprouts in a bioreactor

The study utilized fresh fourth-day Chenopodium formosanum sprouts as the substrate for Rhizopus oligosporus fermentation. The resultant products showed higher antioxidant capacity than those from C. formosanum grains. Compared to traditional plate fermentation (PF), fermentation in a bioreactor (BF) (35 degrees C, 0.4 vvm aeration at 5 rpm) led to higher free peptide content (99.56 +/- 7.77 mg casein tryptone/g) and enzyme activity (amylase, glucosidase, and proteinase are 2.21 +/- 0.01, 54.57 +/- 10.88, and 40.81 +/- 6.52 U/g, respectively) than traditional plate fermentation (PF). Using mass spectrometry analysis, two peptides TDEYGGSIENRFMN and DNSMLTFE-GAPVQGAAAITEK were predicted to possess high bioactive properties as DPP IV and ACE inhibitors. Addi-tionally, over twenty new metabolites (aromatics, amines, fatty acids, and carboxylic acids) were discovered in the BF system compared to its PF counterpart. Results suggest that using a BF system to ferment C. formosanum sprouts is an appropriate method to scale-up fermentation and enhance nutritional values as well as bioactivities.

Automated summary

The study used fresh fourth-day Chenopodium formosanum sprouts as the substrate for Rhizopus oligosporus fermentation. The resultant products had higher antioxidant capacity compared to C. formosanum grains. Fermentation in a bioreactor (BF) led to higher free peptide content and enzyme activity than traditional plate fermentation (PF), as well as the discovery of over twenty new metabolites.