The Bioactivity of byproducts from the blackberry juice industry

Introduction

Blackberry (Rubus sp.) is a red fruit with great potential as a functional ingredient thanks to its composition rich in antioxidants. This work aimed to characterize and study the bioactivity of two byproducts (skins and seeds) from the blackberry juice industry.

Methods

To achieve this objective, “in vitro” gastrointestinal digestion and colonic fermentation were carried out on the byproducts [1]. The phenolic composition, antioxidant capacity (ABTS, DPPH and FRAP) and the genotoxicity of the products and their gastrointestinal digestion and colonic fermentation fractions were analyzed [2]. The effect of the colonic fermentation fraction on the composition of the intestinal microbiota was also analyzed by qPCR.

Results

Byproducts are rich in phenolic compounds that undergo transformations during digestion and fermentation. These changes modified the antioxidant profile, with skin samples exhibiting the highest bioactivity. The “in vitro” genoprotective effect of gastrointestinal digestion and colonic fermentation was concentration-dependent. The colonic fermentation of blackberry skin and seed samples modulated the gut microbiota, promoting the growth of bacterial Bifidobacterium and Lactobacilli, which are associated with a beneficial microbiota due to their known anti-inflammatory and immune-regulating effects on the intestinal barrier.

Conclusions

These results contribute to giving added value to these byproducts for their potential application as functional ingredients in foods.

References

[1] Minekus, M., Alminger, M., Alvito, P., Ballance, S., Bohn, T., Bourlieu, C., … Brodkorb, A. (2014). A standardised static in vitro digestion method suitable for food - an international consensus. Food & Function, 5(6), 1113–1124.

[2] Rivero-Pérez, M. D., Muñiz, P., & González-Sanjosé, M. L. (2007). Antioxidant Profile of Red Wines Evaluated by Total Antioxidant Capacity, Scavenger Activity, and Biomarkers of Oxidative Stress Methodologies. Journal Of Agricultural And Food Chemistry, 55(14), 5476-5483.

This work was supported by Government of Spain (Project A16Z02).