Local and underutilised fruits as a source of nutraceutical molecules: bioactive compounds in Mespilus germanica L

Medlar (Mespilus germanica L.) has been cultivated in several Asian and European countries for medical/food use for many years. As scarce information is available outside Southwest Asia, this study aimed to increase the knowledge of this local and underutilised fruit in Italy as a source of bioactive compounds. Total polyphenolic content (TPC) and antioxidant capacity (AOC) were evaluated by spectrophotometric methods, while the main phytochemical compounds were identified and quantified by HPLC fingerprint. Even if many compounds are variable and decrease during ripening, this research reported the presence of considerable amounts of bioactive compounds in ripe medlar fruits, which resulted particularly rich in monoterpenes (total: 1380.26 ± 48.06 mg/100 gFW; in particular γ-terpinene 922.77 ± 31.61 mg/100 g of fresh weight or FW) and organic acids (total: 963.05 ± 33.21 mg/100 gFW; in particular, malic and citric acid: 406.50 ± 5.25 and 380.99 ± 13.11 mg/100 gFW, respectively), with high values of TPC (138.58 ± 10.03 mg/100 gFW) and AOC (6.59 ± 2.35 mmol Fe2+/kgFW), revealing the benefits of this fruit as a source of antioxidants and anti-inflammatory agents. Bioactive compound content of M. germanica extracts exhibited high variability in different geographic areas, that may depend on several biotic and abiotic factors, and many compounds showed a decreasing trend losing properties during the ripening, but the presence of health-promoting agents was confirmed by the high levels of bioactive compounds observed in the analysed fruit and highlighted the necessity of enhancing the propagation of the medlar in the Italian peninsula as fresh fruit and high-quality nutritional and health-promoting ingredient.