[In vitro evaluation of the bioactive potential of new powdered food ingredients - products of waste-free processing of Allium sativum L.]

Abstract

Garlic husk and pomace remain understudied, limiting their rational use and the development of new food ingredients. Producing powdered ingredients from fermented pomace and husk could address waste disposal issues and create new products with targeted functional properties. The objective of the research was a comparative in vitro evaluation of the antimicrobial and anti-inflammatory potential of powdered food ingredients from fermented garlic bulbs, pomace, and husk (Allium sativum L.).

Material and methods: The study used powders from «Dobrynya» garlic and its processing by-products. Three types of samples were obtained: cloves, meal (pomace), and husks. Part of the samples underwent thermal fermentation (70 °C, 30 days). All materials were dried and ground to a particle size of <0.25 mm. Total phenolic content was determined using the Folin-Ciocalteu method; S-allylcysteine and melanoidins were analyzed spectrophotometrically. Antioxidant activity was assessed by the ability to scavenge the 2.2-diphenyl-1-picrylhydrazyl (DPPH) radical and the 2.2'-azinobis[ 3-ethylbenzothiazoline-6-sulfonic acid] (ABTS⁺) radical cation. Antimicrobial and anti-inflammatory activity was evaluated using specific enzyme test systems based on glutathione reductase, catalase, and NO-synthase. All experiments were performed in triplicate. Data were processed using methods of variation statistics with the application of Tukey's test (p<0.05).

Results: It was established that non-microbial fermentation (70 °C, 30 days) significantly enhances the antioxidant potential of garlic processing products. The content of phenolic compounds, S-allylcysteine, and melanoidins in fermented bulbs and meal increased by 3-25 times, which correlated with a rise in ABTS and DPPH activity. Fermented bulbs and meal exhibited pronounced anti-inflammatory activity (iNOS inhibition by 32-35%) and moderate antimicrobial action (catalase inhibition up to 34.5%). The strongest inhibition of catalase was shown by fresh garlic powder (56.6%). The high biological activity of fermented garlic meal was confirmed - its indicators (antioxidant, anti-inflammatory activity) were comparable to those of fermented bulbs. The obtained data confirm the feasibility of reclassifying garlic processing waste (meal) into the category of functional food ingredients with antioxidant, anti-inflammatory, and preservative properties.

Conclusion: In vitro experiments demonstrated antimicrobial and anti-inflammatory activity of black garlic and fermented pomace powders, supporting their potential as functional ingredients.