Fermenting kale enhances its functional food properties by increasing accessibility of key phytochemicals and reducing antinutritional factors.
Fermenting kale (L.) enhances its functional food properties by increasing accessibility of key phytochemicals and reducing antinutritional factors.
AI Summary
Key Findings
Abstract
The properties of kale as a functional food are well established. We sought to determine how fermentation further enhances these properties. We tested different fermentation conditions: (i) spontaneous fermentation with naturally occurring bacteria, (ii) spontaneous fermentation with 2% salt, (iii), (iv), (v) mixture ofand, (vi) mixture of,, andWe quantified selected bioactive components using high-performance liquid chromatography (HPLC) and antinutritional factors using a gravimetric method and spectrophotometry. We then determined (i) the antioxidant capacity of the vegetable, (ii) anti-inflammation capacity, and (iii) the surface microbiota composition by 16S sequencing. All fermentation methods imparted some benefits. However, fermentation with mixed culture ofandwas most effective in increasing polyphenols and sulforaphane accessibility, increasing antioxidant activity, and reducing antinutritional factors. Specifically, fermentation withincreased total polyphenols from 8.5 to 10.7 mgGAE/g (milligrams of gallium acid equivalent per gram) and sulforaphane from 960.8 to 1777 μg/g (microgram per gram) but decreased the antinutritional factors oxalate and tannin. Total oxalate was reduced by 49%, while tannin was reduced by 55%-65%. The antioxidant capacity was enhanced but not the anti-inflammation potential. Both unfermented and fermented kale protected equally against lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophages and prevented increases in inducible nitric oxide synthase (iNOS), tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and interleukin-6 messenger RNA (IL-6 mRNA) expression by 84.3%, 62%, 68%, and 85.5%, respectively. Unfermented and naturally fermented kale had high proportions of sulfur reducing Desulfubrio and Proteobacteria usually associated with inflammation. Fermenting withand/orchanged the bacterial proportions, reducing the Proteobacteria while increasing the generaandIn summary, fermentation enhances the well-known beneficial impacts of kale. Fermentation with mixed cultures ofandimparts higher benefits compared to the single cultures or fermentation with native bacteria present in the vegetable.
Affiliation
Ujjwol Subedi
External References
- PubMed ID:
- 39139952
Comments
Sign in or create a free account to join the conversation.
Sign in to commentBe the first to comment.