Properties of green extracted bioactive compounds from buckwheat husk

Buckwheat husk, the main byproduct of buckwheat processing, is rich in fiber and has good potential as a source of bioactive peptides and polyphenols. This study evaluates the effectiveness of “green” extraction methods, specifically Microwave Assisted Extraction (MAE) and Ultrasound Assisted Extraction (UAE), for extracting polyphenolic compounds from buckwheat husk, using water-based media as the extractant. These methods were compared to a conventional acidified methanol extraction. The bioactive compound profiles of the different extracts were evaluated in terms of their relative abundance and antioxidant activity. The results indicate that the "green" extraction methods yield higher amounts of polyphenols and maintain significant antioxidant activity compared to the conventional method. The bioactive extracts exhibited considerable anti-inflammatory effects when tested in vitro using a Caco 2 cell model, and inhibitory activity towards enzyme involved in the glucose metabolism. Overall, these findings emphasize the potential of these compounds and the advantages of using sustainable extraction methods, highlighting their possible applications in both food and non-food products. This investigation was supported in part by the National Recovery and Resilience Plan (NRRP), (Mission 4, Component 2, Investment 1.3 - Call for tender No. 341 of 15/03/2022) of the Italian Ministry of University and Research, funded by the European Union–NextGenerationEU, in the frame of the project “Research and innovation network on food and nutrition: Sustainability, Safety and Security (ON Foods).