Evolution and kinetics of monosaccharides,disaccharides and α-galactosides during germination of lentils

The effect of light and seed rinsing during the germination of lentil seeds (Lens culinaris var. vulgaris, cultivar Magda-20) on the level of monosaccharides, disaccharides and α-galactosides (raffinose, ciceritol and stachyose) was investigated. The total soluble sugar content corresponded to about 9% of the mature seed weight, about 65% of which was α-galactosides. Germination brought about a large decrease in α-galactosides: 18% to 40% losses after 3 days and 100% after 6 days. However, glucose, which was not detected in ungerminated seeds, as well as fructose and sucrose gradually increased during germination. The content of α-galactosides decreased more rapidly when germinating seeds were given 6 h light per day, but under these conditions there was also a major reduction in the levels of fructose, glucose and sucrose. Seeds rinsed daily showed a greater reduction of α-galactosides and an increase in the levels of fructose, glucose and sucrose. When seeds were germinated for 10 days in the dark with daily rinsing, the content of α-galactosides decreased gradually during the first 4 days and they were not detected after 6 days. Under these conditions, fructose, glucose and sucrose, which represented about 3% of the mature seed weight, started increasing after day 2 and represented more than 13% of the germinated seed dry weight after 10 days.     

Time dependence of bioactive compounds and antioxidant capacity during germination of different cultivars of broccoli and radish seeds

Optimisation of the germination process of different cultivars of broccoli (Brassica oleracea var. italica cv. Lucky, cv. Tiburon and cv. Belstar) and radish (Raphanus sativus cv. Rebel and cv. Bolide) seeds in relation to the content of glucosinolates (GLS), vitamin C and total antioxidant capacity was carried out in order to maximise the health-promoting properties of Brassica sprouts. The content of total and individual GLS varied between species, among cultivars, and germination time. Glucoraphanin in broccoli and glucoraphenin in radish were the predominant GLS in raw seeds (61–77 and 63–129 μmol/g DM, respectively) and, although their content decreased during germination, they were maintained in rather large proportions in sprouts. Vitamin C was not detected in raw seeds and its content increased sharply in broccoli and radish sprouts (162–350 and 84–113 mg/100 g DM, respectively). Raw brassica seeds are an excellent source of antioxidant capacity (64–90 and 103–162 μmol Trolox/g DM in broccoli and radish, respectively) and germination led to a sharp increase. Germination of broccoli cv. Belstar and radish cv. Rebel for 4 days provided the largest glucoraphanin and glucoraphenin content, respectively, and also brought about large amounts of vitamin C and antioxidant capacity.     

Alpha-Galactosides: Antinutritional Factors or Functional Ingredients?

This review focuses on updated information about alpha-galactosides, their chemical structure, biosynthesis, plant physiological functions, occurrence in foods, positive and negative physiological effects in animals, changes during food processing, and their potential application as prebiotics in the food industry. Although alpha-galactosides are considered as the main flatus-causing factors, they are also involved in several important functions during plant and seed development and beneficially stimulate the growth and activity of living bifidobacteria and lactobacilli in the human colon. We focus here also on legumes as a source of this kind of prebiotics as potential health promoters.     

Effect of phytic acid degradation by soaking and exogenous phytase on the bioavailability of magnesium and zinc from Pisum sativum, L.

The effect of dephytinization of Pisum sativum, L. flour on the bioavailability of Mg and Zn was evaluated in growing rats. Processing of legume flours under optimal conditions for phytase activity (pH 5.5, 37 °C, 60 min) and subsequent removal of the soaking solution led to a 42 and 61% reduction in the content of Mg and Zn, respectively. Treatment with phytase led to an additional reduction in the concentration of the above-mentioned seed flour components, compared to the raw pea flour (69% and 74% for Mg and Zn, respectively). The considerable reduction in the content of inositol phosphates with high degree of phosphorylation attained under both processing conditions did not affect the digestive utilization of Mg, whereas the metabolic utilization of this mineral increased significantly. The digestive and metabolic utilization of Zn increased significantly in response to both processes assayed, reaching the highest values in the experimental group that was fed the phytase-treated pea flour diet. The amount of Mg retained by the experimental animals was reflected in the content of this mineral in the different tissues studied (femur, sternum, kidney, and heart), whereas no correlation was found in the case of Zn.     

Effect of treatment with α‐galactosidase,tannase or a cell‐wall‐degrading enzyme complex on the nutritive utilisation of protein and carbohydrates from pea (Pisum sativum L.) flour

The effect of treatment with α‐galactosidase, tannase or a cell‐wall‐degrading enzyme complex under optimal conditions of pH, temperature and length of incubation time on the chemical composition and nutritive utilisation of protein and carbohydrates from pea (Pisum sativum L.) flour was studied. Soaking of pea flours in combination with enzyme treatment led to reductions of 77–90% in the levels of α‐galactosides, and of 60–80% in the levels of trypsin inhibitor activity, increasing the content of total available sugars, which was highest in the pea flour treated with the cell‐wall‐degrading enzyme complex. All the treatments assayed caused a significant improvement in daily food intake, whereas the nutritive utilisation of protein was not increased in any of the pea products tested when compared to the raw pea flour. However, all the soaking and enzymatic treatments led to a significant improvement in daily weight gain associated with a higher dietary intake of food and total available sugars. Copyright © 2007 Society of Chemical Industry     

Changes in carbohydrates during germination of lentils

Summary The effect of germination on soluble carbohydrates, total and digestible starch, and components of dietary fiber (neutral detergent fiber, cellulose and hemicellulose) in two varieties of lentils (Lens culinaris medicus var. vulgaris and variabilis) were investigated. In germinated lentils the amount of total soluble sugars decreased (from 4.3% to 2.0% and from 5.3% to 2.2%, respectively); glucose, not present in raw seeds, was relatively high (0.6% and 0.7%), fructose increased slightly, and sucrose decreased slightly. The oligosaccharides of the raffinose family disappeared from germinated seeds. Total starch decreased considerably in germinated lentils (from 60.3% to 41.4% and from 57.4% to 36.4%), but the digestibility of the starch was greatly improved. In germinated lentils, the content of neutral detergent fiber and hemicellulose were lower but that of cellulose and lignin were higher than in raw lentils. Thus, the nutritive value of both varieties of lentils may increase with germination processes.

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Veränderungen im Kohlenhydratgehalt in keimenden Linsen

Zusammenfassung In der vorliegenden Arbeit wurde der Einfluß der Keimung auf die Gehalte an löslichen Kohlenhydraten, Gesamt- und verdaulicher Stärke und Komponenten der Rohfaser (neutral detergent fiber, Cellulose und Hemicellulose), in zwei Linsensorten (Lens culinaris medicus var. vulgaris und variabilis) untersucht. Der Gesamtzuckergehalt nimmt durch die Keimung bei beiden Sorten ab (von 4,3% bis 2,0% und von 5,3% bis 2,2%). Glucose, die sich in rohen Samen nicht findet, lag bei 0,6% und 0,7% in den gekeimten Linsen. Fructose und Sucrose änderten sich nur wenig. Die Raffinose-Oligosaccharide sind bei den gekeimten Linsen nicht vorhanden. Die Gesamt-Stärke nimmt deutlich während der Keimung ab (von 60,27% bis 41,39% und von 57,41% bis 36,39%), aber die Verdaulichkeit der Stärke wurde signifikant verbessert. Die Gehalte an neutral detergent fiber und Hemicellulose bei gekeimten Linsen waren niedriger als bei rohen Linsen, aber die Cellulose- und Ligningehalte waren nach der Keimung größer. Der Proteinnährwert bei beiden Linsensorten kann durch die Keimung verbessert werden.

     

Role of volatilization in changing TBA and MTBE concentrations at MTBE-contaminated sites

Tertiary butyl alcohol (TBA) is commonly found as an impurity in methyl tertiary butyl ether (MTBE) added to gasoline. Frequent observations of high TBA, and especially rising TBA/MTBE concentration ratios, in groundwater at gasoline spill sites are generally attributed to microbial conversion of MTBE to TBA. Typically overlooked is the role of volatilization in the attenuation of these chemicals especially in the vadose zone, which is a source of contamination to groundwater. Here we show that volatilization, particularly through remediation by vapor extraction, can substantially affect the trends in TBA and MTBE concentrations and the respective mass available to impact groundwater aquifers, through the preferential removal of more volatile compounds, including MTBE, and the apparent enrichment of less volatile compounds like TBA. We demonstrate this phenomenon through numerical simulations of remedial-enhanced volatilization. Results show increases in TBA/MTBE concentration ratios consistent with ratios observed in groundwater at gasoline spill sites. Volatilization is an important, and potentially dominant, process that can result in concentration trends similar to those typically attributed to biodegradation.