Optimizing bioreactor conditions for Spirulina fermentation by Lactobacillus helveticus and Kluyveromyces marxianus: Impact on chemical & bioactive properties

Bioresour Technol. 2024 Jul:403:130832. doi: 10.1016/j.biortech.2024.130832. Epub 2024 May 15.

Abstract

This study focused on optimizing the production of fermented Spirulina (FS) products using a bioactivity-guided strategy with Lactobacillus helveticus B-4526 and Kluyveromyces marxianus Y-329 in a 3-L bioreactor. Various operating conditions, including aeration rates and pH modes, were tested. While both microorganisms thrived under all conditions, the "cascade" mode, controlling dissolved oxygen, enhanced protein hydrolysis and antioxidant activity, as confirmed by SDS-PAGE and DPPH/TEAC assays, respectively. Screening revealed that "cascade" FS significantly decreased viability of colon cancer cells (HT-29) in a dose-dependent manner, with up to a 72 % reduction. Doses ≤ 500 μg mL-1 of "cascade" FS proved safe and effective in suppressing NO release without compromising cellular viability. Additionally, "cascade" FS exhibited diverse volatile organic compounds and reducing the characteristic "seaweed" aroma. These findings highlight "cascade" FS as a promising alternative food source with improved bioactive properties, urging further exploration of its bioactive compounds, particularly bioactive peptides.

Keywords: Alternative protein; Functional foods; Microalgae; Operational conditions; Sustainability.

MeSH terms

  • Antioxidants / metabolism
  • Antioxidants / pharmacology
  • Bioreactors*
  • Cell Survival / drug effects
  • Fermentation*
  • HT29 Cells
  • Humans
  • Hydrogen-Ion Concentration
  • Kluyveromyces* / metabolism
  • Lactobacillus helveticus* / metabolism
  • Spirulina* / metabolism
  • Volatile Organic Compounds / metabolism
  • Volatile Organic Compounds / pharmacology

Substances

  • Antioxidants
  • Volatile Organic Compounds

Supplementary concepts

  • Kluyveromyces marxianus