Valorization of Bioactive Compounds from Lingonberry Pomace and Grape Pomace with Antidiabetic Potential

What if the leftover pomace from your berry juice could help fight diabetes? New research shows that grape and lingonberry waste harbor compounds with antidiabetic potential.

Every year, the fruit-processing industry discards tons of pomace—the skins, seeds, and pulp left after juicing. But this "waste" is a goldmine of bioactive polyphenols. In a new study, scientists turned to lingonberry and grape pomace to extract these valuable compounds using two green techniques: ultrasound-assisted extraction (UAE) and accelerated solvent extraction (ASE). Both methods used a 50% ethanol solvent and produced hydroalcoholic extracts rich in polyphenols.

The extracts were then filtered through micro- and ultrafiltration membranes and analyzed via UV-Vis spectrophotometry and HPLC-PDA. The most striking finding? The extracts inhibited key enzymes linked to diabetes—α-amylase and α-glucosidase. Grape pomace extracts were particularly potent, with IC50 values nearly identical to acarbose, a standard antidiabetic drug. For α-amylase, grape pomace had an IC50 of 0.30 µg/mL versus acarbose's 0.30 µg/mL; for α-glucosidase, 0.60 µg/mL versus 0.57 µg/mL.

Statistical analysis revealed significant differences between the two extraction methods, highlighting that technique matters. This research underscores the potential of agro-industrial residues as a sustainable source of bioactive compounds. By valorizing these by-products, we can support circular economy principles and create new nutraceutical or pharmaceutical ingredients—turning waste into wellness.

Key Points

• Grape pomace extracts rival antidiabetic drug acarbose in enzyme inhibition.
• Green extraction (UAE, ASE) recovers polyphenols from fruit waste.
• Lingonberry and grape pomace show potential for circular economy valorization.