Allium ampeloprasum Propagation Organ (Japanese Garlic): Polyphenol Profiling Under Different Drying and Extraction Conditions

The genus Allium comprises more than 1100 species, where Allium ampeloprasum can be found. It is a species that, until now, has remained relatively unexplored, as well as its propagation organ known as Japanese garlic, even though it is increasingly cultivated in Mexico. The aim of this study was to evaluate phenolic profiles using Ultra-High-Performance Liquid Chromatography (UHPLC), as well as to conduct an exploratory study of total polyphenol content by Folin–Ciocalteu assay and antioxidant capacity by DPPH inhibition in husks, peeled and whole propagation organs subjected to different drying methods and extraction solvents. In order to observe the influence of these factors on polyphenol extraction using green extraction technologies, such as natural eutectic solvents (NADESs), it was observed that the drying method is crucial for the extraction of flavonoid-type polyphenols, while NADESs allowed for the selective extraction of antioxidant and anti-inflammatory compounds. The highest total polyphenol content was obtained in freeze-dried husks extracted with 60% hydrated NADES (384.81 ± 15.38 mg GAE/100 g). The greatest DPPH radical inhibition was observed in freeze-dried husks with 68% hydrated NADES (93.08 ± 0.58%), where polyphenols such as catechin, chlorogenic acid, rutin, quercetin + luteolin, kaempferol, and hesperidin stood out. This highlights the potential of the propagation organ of A. ampeloprasum, especially its husks, as a source of phenolic compounds, supporting the valorization of agro-industrial waste from garlic, since the results obtained exceed those previously reported for the Allium sativum variety.