Influence of high-pressure processing on nutritional composition and bioactive compounds of Phaseolus coccineus L.

The influence of high-pressure processing (HPP) prior to cooking on nutritional composition and bioactive compounds content of four varieties of Phaseolus coccineus L. was studied. Cooking and HPP+C increased the protein content. However, minerals, total carbohydrates, ciceritol and α-galactosides were reduced. Fat was not affected by cooking but decreased after HPP+C. For dietary fiber, the behavior observed was different depending on the sample and the treatment applied. HPP+C could be considered a good processing technology to retain the advantageous lower myo-inositol phosphates isoforms and supply prebiotic oligosaccharides. The trypsin inhibitors activity was lower in the cooked and HPP+C samples; however, there were no significant differences between both thermal treatments. Thus, HPP+C reduced cooking time and preserving or improving the nutritional composition of the beans and their bioactive compounds content.

Composition of two Spanish common dry beans (Phaseolus vulgaris), 'Almonga' and 'Curruquilla', and their postprandial effect in type 2 diabetics.

BACKGROUND: Legume consumption has been associated with a lower risk of developing type 2 diabetes. However, the type of legume is a modifier of its effect. Two Spanish dry bean varieties-white ('Almonga') and cream ('Curruquilla')-were analyzed and used in a postprandial study in type 2 diabetics to assess glucose, insulin and triacylglycerol in blood. RESULTS: 'Curruquilla' variety had higher total galactoside (stachyose, mainly), trypsin inhibitors and lectin content than 'Almonga'. The canning liquid was discarded prior to the analysis and the bean consumption by the subjects. The canning process reduced the total α-galactoside content (>50%), practically eliminated trypsin inhibitors, and no lectin content was found. After bean consumption, maximum glucose was obtained at 60 min and was three times lower than that in bread. After bean intake, maximum insulin was produced 60 min with 'Almonga' and occurred later (90 min) with 'Curruquilla' and bread. After 'Almonga' intake, the area under the curve response of triglycerides was 14% lower compared to bread (P = 0.013). CONCLUSIONS: 'Almonga' and 'Curruquilla' are similar in the content of the nutritional but not in that of the antinutritional components. Both beans showed similar effects on blood glucose and insulin in type 2 diabetics and marked differences compared to those of bread in terms of magnitude and time course, but only 'Almonga' rendered a significant reduction in the triglyceridemic response.

Phenological changes in the concentration of alkaloids of Carex brevicollis in an Alpine rangeland.

Carex brevicollis (Cyperaceae) is a plant of mesic grasslands in calcareous mountains of southern Europe. It contains two different ß-carboline alkaloids, brevicolline and brevicarine, the first of which is thought to produce abortions in mammals. In the rangeland of Aliva, within the Picos de Europa massif in northern Spain, the abundance of Carex brevicollis has been linked with the occurrence of teratogenesis in early gestating cows grazing in early summer. The concentration of alkaloids was measured in the summers of 2007 and 2008, at intervals of 2 weeks, at different altitudes within the rangeland (1,350, 1,600, and 1,850 m) and from different parts of the sedge (leaves, reproductive stems, and inflorescences). Estimated growing degree days were related to the flowering phenology of Carex brevicollis and were used to analyse its relation with the concentration of alkaloids. Brevicarine concentration was higher in inflorescences and brevicolline in leaves. Although it also depended on the zone and year, the concentrations of both alkaloids were related one to another in leaves and inflorescences but not in stems. Both alkaloids decreased with growing degree days in the inflorescences and showed no response in leaves. Our findings suggest that brevicarine, not brevicolline, could be the teratogen in pregnant cattle in this region. This hypothesis is supported by the observed frequent consumption of inflorescences and scarce consumption of leaves of Carex brevicollis by grazing livestock, and also by the coincidence of the toxicity in early pregnant cows with the flowering time of the sedge.