[Chemical composition of 2 wild vegetable species compared with chard]. / Estudio de la composición química, de dos especies vegetales silvestres en comparación con acelga.

The nutritional quality of two wild vegetable species, Kochia scoparia (Ks) and Chenopodium album (Cha) was evaluated and compared with Beta vulgaris var. cicla(chard) (Bv), in order to propose their domestication as alternative protein sources. Chemical percentual analysis (AOAC), gaseous chromatography fatty acid determination, and antinutrient searching (by chemical, enzymatic and immunological method) were performed. Protein quality was determined by the following indexes: net protein utilization (NPU), true digestibility (tD) and biological value (BV). The three species exhibited similar protein concentration values, 25.8, 25.0 and 22.1 g/100 g for Ks, Cha and Bv, respectively. Kochia scoparia showed the highest value for fatty acid analysis (82%), with predominance of linolenic acid. Since the samples were subjected to boiling, the amounts of antinutrients found can be considered to be within levels not affecting health. As regards the biological quality, the obtained values for Ks, Cha and Bv, respectively, were: NPU: 68.0 +/- 0.4, 55.0 +/- 6.1 and 56.0 +/- 4.2; tD 70.0 +/- 0.7, 71.0 +/- 4.0 and 76.0 +/- 8.2; BV: 97, 77 and 74. The analysis of the biological quality indexes gave highest nitrogen profit for Ks. These results indicate that Kochia scoparia is suitable for the objective proposed.

Nutrient and antinutrient composition of Amaranthus muricatus.

The chemical and nutritional composition of the aerial parts of Amaranthus muricatus was assessed. This is a wild plant growing well in arid and poor soil, which are not suitable for cereals. The material under study was boiled, dried and ground and then evaluated for chemical, nutritional and antinutritional properties. Protein concentration of the amaranth flour was 15.74 g/100 g and total dietary fiber content was high (53.81 g/100 g), with 79% coming from insoluble dietary fiber. The calcium content was 1533 mg/100 g and the Ca/P ratio (5.94) was markedly higher than the value suggested in the 1989 Recommended Dietary Allowances. Fifty-nine percent of the fatty acids present were unsaturated with linoleic acid accounting for 40% of the total fatty acid content. Nitrate, hemagglutinin, trypsin inhibitor and saponin contents were within the non-critical values. Net protein utilization (NPU), true digestibility (tD) and biological value (BV) measurements indicated a nitrogen gain of 74% that of casein. The results of this study indicate a nutritive potential for the A. muricatus leaves, therefore, domestication of this plant is suggested along with assessment of its chemical and nutritional properties.