[Suitability of wild underexploited vegetables from the Argentine Chaco as a food resource]. / Vegetales silvestres sub explotados del Chaco argentino y su potencial como recurso alimenticio.

The nutritional value of wild underexploited vegetable samples collected in the Argentine Chaco was investigated. Leaves from Hipochaeris sp.-, Coronopus didimus and Portulaca olearacea; fruits from Zyziphus sativa, Brumelia obtusifolia and Eugenia uniflora; and roots of Canna coccinea were included in this work; several separate samples being taken at least during two consecutive harvesting seasons. Values for moisture, protein, total lipids, crude fiber, ash, reducing and total sugars, starch, total pectins and energy are given. Mineral micronutrient contents are reported for calcium, potassium, magnesium, iron and phosphorus, as well as vitamin values (ascorbic acid and beta-carotene). Higher concentrations of macronutrients were found in the leafy vegetables (32-50 Kcal/100 g) than in commercially exploited cultivars (14-30 Kcal/100 g), as shown by an increased energy value, the protein content of Portulaca olearacea (3.74 g/100 g) being highly remarkable. Unusually high micronutrient figures were also determined in Coronopus didimus, with 172.3; 3.98, and 46.7 mg/100 g, for calcium, iron and magnesium, respectively. In general, fruits also showed higher macronutrient contents, with the exception of proteins, with less but constant values (1.58 to 1.74 g/100 g), although contributing more energy than commercial cultivars (70 to 147 Kcal/100 g). Equally important proved to be the provitamin A content in Eugenia uniflora (11.98 mg/100 g). Roots of Canna coccinea revealed the lowest energy value (34 Kcal/100 g) but surprisingly, the highest content of phosphorus of all the species under study.

Composición de nutrientes en especies vegetales autóctonas de la región Chaqueña, Argentina / Nutrients in wild vegetable products of the Argentine Chaco

Se investigaron nutrientes en productos vegetales silvestres del Monte Chaqueño Argentino. Las especies evaluadas fueron: Rumex sp., Amaranthus quitensis y Taraxacum officinale (vegetales de hoja); Morrenia adorata, Passiflora sp. (en dos estados de maduración) y Eugenia myrciantes (frutos); y polen de las flores de Typha domingenis. El muestreo se realizó durante tres períodos estacionales consecutivos. Se consignan los resultados de las determinaciones de humedad, proteínas, lípidos totales, fibra bruta, cenizas, azucares totales y reductores, almidón, pectinas totales y cálculo de aporte energético. Los micronutrientes minerales, se analizaron mediante espectrofotometría de absorción atómica, e involucró: calcio, sodio, potasio, magnesio, hierro. Se determinó además, el contenido de fósforo por colorimetría, vitamina C mediante titulación con 2-6 diclorofenolindofenol y beta-carotenos por espectrofotometría. Se realizó el test de comparación de medias para las muestras de Mburucuya en los dos estados de maduración. En los vegetales de hoja se encontró una mayor concentración de los macronutrientes que en especies similares pero cultivadas, como la acelga, espinaca y achicoria, lo cual se traduce en un aporte energético superior (promedio: 33-60 Kcal/100 g en hojas silvestres, frente a 14-30 Kcal/100 g en las cultivadas). De los micronutrientes investigados, se destacaron los tenores de Ca, fe y Mg hallados en Amaranthus quitensis (274.3, 6.4, 136.2 mg/100 g, respectivamente), además del nivel de vitamina C de Rumex sp. (48.9 mg/100 g). En general, los frutos también evidenciaron concentraciones más elevadas de macronutrientes y aportes calóricos que otros cultivados, como las manzanas. Resultaron de interés los valores de macro y micronutrientes encontrados en el polen de T. domingensis, con un aporte calórico de 287.7 Kcal/100 g

[Nutrient content in vegetable species from the Argentine Chaco]. / Composición de nutrientes en especies vegetales autóctonas de la región Chaqueña, Argentina.

The nutrient composition was investigated in wild vegetable products grown in the Argentine Chaco. The evaluated species were: Rumex sp., Amaranthus quitensis and Taraxacum officinale, as vegetable leaves; Morrenia odorata, Passiflora sp. (in two ripening stages) and Eugenia myrciantes as fruits; and the pollen of the flowers of Typha domingensis. Sampling was performed during three harvesting seasons. Values for protein, total lipid, crude fiber, ash, reducing and total sugar, starch, total pectin and computed energy value are given. Mineral values are reported for: calcium, sodium, potassium, magnesium, iron and phosphorus. Vitamin values are given for ascorbic acid and beta-carotene. Comparison of two means test was employed to test the significant differences among the means. In the wild leaves, higher concentrations of the macronutrients were found thean in commercially exploited cultivars such as swiss chard, spinach and chicory. Also higher energy value: 33-60 Kcal against 14-30 Kcal/100 g. Unusually high levels of calcium, iron and magnesium were found for Amaranthus quitensis (274.3, 6.4 and 136.2 mg/100 g, respectively) and 48.9 mg/100 g of ascorbic acid were found in Rumex sp. As a rule, all these wild fruits exhibited higher amounts of macronutrients and energy value than cultivated species such as apples (Mallus sp). The most interesting results were for T. domingensis pollen regarding its macro and micronutrient composition with an energetic value of 287.7 Kcal/100 g.