Nutritional value of unconventional leafy vegetables grown in the Cerrado Biome/Brazil

Abstract Traditional or unconventional vegetables have a wide and rich genetic variability; it is possible to found in farmers markets and other forms of commercialization, in regions where they are part of the food and cultural context. Species of leafy vegetables such as Rumex acetosa, Basella alba, Tropaeolum majus, Pereskia aculeata, Stachys byzantina, Xanthosoma taioba, Hibiscus sabdariffa, among others, totaling 14 species, were grown under the conditions of the Cerrado Biome/Brazil and characterized as to their proximate and mineral composition. Dietary fiber content of Stachys byzantina was the highest (13.21 g 100 g-1) among the species. The potassium content in Lactuca canadenses, Rumex acetosa, Portulaca oleracea, and Hibiscus sabdariffa, exceeds 500 mg 100 g-1. More than 100 mg 100 g-1 of magnesium were found in six species and more than 100 mg 100 g-1 of calcium for another nine species. Values of phosphorus in Talinum paniculatum and Hibiscus sabdariffa were 84.50 mg 100 g-1 and 138.23 mg 100 g-1, respectively. The Hibiscus sabdariffa (2.39 mg 100 g-1) were prominent as good source of zinc. A Rumex acetosa, Portulaca oleracea e Stachys byzantina, plant presented expressive iron contents, above 5 mg 100 g-1. These values are comparable or superior to conventional leafy vegetables and denote the potential of these species for consumption and commercialization, thus a greater dissemination of their nutritional values is necessary.摘要：传统蔬菜与非常规蔬菜均具备广泛且丰富的遗传变异；在将其纳入饮食与文化体系的地区，农贸市场及其他商业化流通渠道中均可觅得其踪迹。本研究选取酸模（Rumex acetosa）、落葵（Basella alba）、旱金莲（Tropaeolum majus）、刺叶仙人掌（Pereskia aculeata）、绵毛水苏（Stachys byzantina）、泰奥巴芋（Xanthosoma taioba）、玫瑰茄（Hibiscus sabdariffa）等共计14种叶菜类物种，在巴西塞拉多生物群区（Cerrado Biome）的栽培条件下进行种植，并对其常规营养成分与矿物质组成开展系统表征分析。其中，绵毛水苏的膳食纤维含量最高，达13.21 g·100g⁻¹。加拿大莴苣（Lactuca canadenses）、酸模、马齿苋（Portulaca oleracea）与玫瑰茄的钾含量均超过500 mg·100g⁻¹。有6个物种的镁含量突破100 mg·100g⁻¹，另有9个物种的钙含量达到该水平。锥花土人参（Talinum paniculatum）与玫瑰茄的磷含量分别为84.50 mg·100g⁻¹与138.23 mg·100g⁻¹。玫瑰茄的锌含量为2.39 mg·100g⁻¹，属于优质锌来源。酸模、马齿苋与绵毛水苏的铁含量表现突出，均高于5 mg·100g⁻¹。上述营养指标可与常规叶菜媲美甚至更优，彰显了这些物种的食用与商业化潜力，因此有必要进一步推广其营养价值认知。