Qualitative characterization of cultivated and wild edible plants: mineral elements, phenols content and antioxidant capacity

Abstract

This study investigated the qualitative characteristics of several edible wild herbaceous species, including those most consumed in Foggia Province (southern Italy). Analysis of qualitative characteristics was performed for the edible parts of 11 wild species (Beta vulgaris L., Foeniculum vulgare Miller, Centaurea solstitialis L., Cichorium intybus L., Scolymus hispanicus L., Sonchus oleraceus L., Borago officinalis L., Diplotaxis erucoides L., Diplotaxis tenuifolia (L.) DC, Sinapis arvensis L., Portulaca oleracea L.) and three cultivated species (C. intybus, B. officinalis, D. tenuifolia). The plants were collected from areas in the Foggia countryside, and the edible part of each species was analysed for dry matter, protein, cation and anion contents as well as total phenols and antioxidant activities. Among the cations, calcium was the most differentiated among species, ranging 784 mg kg-1 fresh weight (Fw) for B. vulgaris to 5886 mg kg-1 Fw for S. hispanicus. The nitrate contents were also highly variable, from 75 mg kg-1 Fw for C. intybus to 3874 mg kg-1 Fw for D. tenuifolia. Total polyphenols ranged from 1054 mg GAE mg kg-1 Fw for C. solstitialis to 3664 mg GAE mg kg-1 Fw for S. arvensis. Antioxidant activities ranged from 839 mg TE kg-1 Fw for B. vulgaris to 5658 mg TE kg-1 Fw for C. intybus. Significant differences were also noted between wild and cultivated plants in the qualitative parameters. Total polyphenols and antioxidant activity were higher in wild C. intybus and B. officinalis than in their cultivated counterparts. Multivariate analysis (cluster analysis and linear discriminant analysis) allowed integration of the ANOVA data to determine the qualitative characteristics of the wild species that contribute most to group differences. The results of the present study aims at improve the current knowledges about edible wild species as vegetable sources in the Mediterranean diet.

Morphological Diversity and Bioactive Compounds in Wall Rocket (Diplotaxis erucoides (L.) DC.)

“…The contents found in our work were significantly greater than the levels previously determined by Salvatore et al [36], although differences may correspond in part to the different treatment of materials (fresh vs. boiled). In addition, our results highlighted the content in total phenolics in concordance with the work of Disciglio et al [11]. Phenolics are less studied in Brassicaceae than in other botanical families and are usually included in works focused on the study of glucosinolates as secondary metabolites of importance in this family [33,37,38].…”

“…On the other hand, a high content in NO 3 − was also determined. Values were significantly greater than the ones previously established for the species [11,40]. The accumulation of NO 3 − can vary among genotypes [41], but it is strongly affected by growing conditions and crop practices.…”

“…Regarding the nutritional quality, wall rocket may accumulate high levels of vitamin C and phenolic compounds, such as the cultivated rocket crops [9]. However, these species accumulate high amounts of nitrates as well [10][11][12]. Nitrates have been considered for decades as antinutrients with potential negative effects for health [13,14]; thus, the accumulation in foodstuff must be controlled, especially for leafy vegetables.…”

Growing Conditions Affect the Phytochemical Composition of Edible Wall Rocket (Diplotaxis erucoides)

“…Comparable or slightly lower levels have been previously found in cultivated rocket crops [43], usually ranging between 3500-4500 mg kg −1 but reaching 7349 mg kg −1 . Levels described for non-cultivated wall rocket would be between 2000-2500 mg kg −1 [53,54], suggesting that the species tends to increase this accumulation under cultivated conditions. Finally, the increased percentage of moisture was reflected in a greater visual appearance and less coriaceous aspect-traits that are essential for consumer acceptance.…”

Wild and Cultivated Centaurea raphanina subsp. mixta: A Valuable Source of Bioactive Compounds

“…Similarly, Isbilir and Sagiroglu [34] reported a higher antiradical and antioxidant activity and a higher total phenolics content for extracts obtained from wild sheep sorrel (Rumex acetosella L.) plants than extracts from cultivated ones. In the study of Disciglio et al [35], samples from Cichorium intybus L., Borago officinalis L. and Diplotaxis tenuifolia (L.) DC collected from wild and cultivated plants were compared in terms of dry matter, proteins, nitrates and polyphenols content, as well as regarding their antioxidant activity. The reported results showed that wild plants had a higher quality than cultivated counterparts, since they contained higher amounts of the tested nutrients and polyphenols and a lower amounts of anti-nutritional factors such as nitrates [35].…”