Characterization of an Italian landrace of Cyclanthera pedata (L.) Schrad. of herbal and horticultural interest

Caigua (Cyclanthera pedata (L.) Schrad.) is a native species of the Andes. Its fruits are recently gaining attention as herbal and healthy product. A landrace of Caigua traditionally cultivated in Camonica Valley (Italian Alps), called “Ciuenlai” (or “Milione/Milioncino”), is almost unknown. For this reason, the phytochemical, nutritional and ecological (functional strategy) characterization of “Ciuenlai” was carried out. Phytochemical and nutritional analyses were performed considering its fruits, leaves, sprouts, and seeds, and compared with commercial South American plant material. Fruits of “Ciuenlai” showed a similar content of phenolic compounds but a lower content of saponins and flavanones and dihydroflavonols than the comparison samples. Conversely, the content in caffeoylquinic acid (frequently considered a quality marker for herbal use) was four times higher for “Ciuenlai” (0.64 ± 0.04%) comparing with the commercial variety grown in the same area (0.15 ± 0.01%). Interestingly, leaves and sprouts of “Ciuenlai” resulted rich in secondary metabolites, including saponins and flavanones and dihydroflavonols, suggesting that these parts could be eligible for herbal use. Considering the ecological and agronomical features, “Ciuenlai” showed a more ruderal strategy, and different growth, producing more fruits earlier in the season, much smaller than the South American variety. “Ciuenlai” could have developed an ecological adaptation to the peculiar climatic conditions of the mountain areas of Camonica Valley, different from the native area. The herbal use of “Ciuenlai” could be a useful strategy for its valorisation, other than the promotion of this product as typical food.