HS-SPME analysis of the volatiles profile of water celery (Apium nodiflorum), a wild vegetable with increasing culinary interest.

Water celery (Apium nodiflorum) is a wild plant traditionally harvested in some Mediterranean areas for being consumed raw. Despite its appreciated organoleptic properties, the aromatic profile of the fresh vegetable remains to be studied. In the present study, volatile compounds from five wild populations were extracted by the headspace-solid phase microextraction technique, analysed by gas cromatography-mass spectrometry, and compared to related crops. The wild species had a high number of aromatic compounds. It was rich in monoterpenes (49.2%), sesquiterpenes (39.4%) and phenylpropanoids (9.6%), with quantitative differences among populations, in absolute terms and relative abundance. On average, germacrene D was the main compound (16.6%), followed by allo-ocimene (11.9%) and limonene (11.1%). Only in one population, the levels of limonene were greater than those of germacrene D. Among phenylpropanoids, dillapiol displayed the highest levels, and co-occurred with myristicin in all populations except one. These differences may have a genetic component, which would indicate the possibility of establishing selection programmes for the development of water celery as a crop adapted to different market preferences. On the other hand, comparison with related crops revealed some similarities among individual volatiles present in the different crops, which would be responsible of the common aroma notes. However, water celery displayed a unique profile, which was in addition quantitatively richer than others. Thus, this differentiation may promote the use of water celery as a new crop.

Fruit composition diversity in land races and modern pepino (Solanum muricatum) varieties and wild related species.

Pepino (Solanum muricatum) fruits from 15 accessions of cultivated pepino as well as six accessions from wild relatives were evaluated for contents in dry matter, protein, ß-carotene, chlorophylls and seven minerals. Several-fold differences among accessions were found for most traits. Average values obtained were similar to those of melon and cucumber, but the phenolic contents were much higher. Wild species had significantly higher average contents for all traits vs. the cultivated pepino accessions. And, the comparisons among the cultivated pepino varieties showed that the modern varieties were more uniform in composition, and they possessed significantly lower concentrations of protein, P, K, and Zn than local land races. Most of the significant correlations among composition traits were positive. Our studies show that regular consumption of pepino fruits could make a significant contribution to the recommended daily intake of P, K, Fe and Cu as well as to the average daily intake of phenolics. Furthermore, the higher values for most nutrients measured in the wild species and in the local land races indicate that new pepino varieties with improved fruit contents in nutrient and bioactive compounds can be developed.