Aims: This study aims to evaluate the impact of solid-state fermentation (SSF) by Trichoderma reesei on the phenolic content, antioxidant and antimicrobial activities of garden cress seeds (GCS).
Methods and results: The factorial statistical design was employed to optimize the SSF conditions, incubation time, pH, temperature and moisture, for maximum production of the phenolic content and microbial carbohydrate-cleaving enzymes from GCS. The total phenolic content significantly increased from unfermented GCS (401 mg gallic acid equivalent (GAE) 100 g-1 ) to fermented GCS (3600 mg GAE 100 g-1 ) by ninefold. The total antioxidant activity significantly increased in fermented GCS. Fifteen phenolic compounds were detected in fermented GCS with high concentrations compared to 14 in unfermented GCS using high-performance liquid chromatography. A strong correlation between the production of the carbohydrate-cleaving enzymes and the phenolic content of fermented GCS was observed. The phenolic compounds of fermented GCS showed higher antimicrobial activity.
Conclusions: The fermented GCS is a powerful source of phenolic compounds with high antioxidant potentials, which can be used as dietary supplement and antimicrobial agent.
Significance and impact of the study: Solid-state fermentation is a promising technique used for production of added-value bioactive compounds. SSF increased the total phenolic content and antioxidant activity of GCS several folds compared to germination process, which recently studied.
Keywords: antimicrobial activity; antioxidant activity; garden cress; phenolic compounds; solid-state fermentation.
© 2019 The Society for Applied Microbiology.