Regional assessment of evaporation from agricultural irrigation reservoirs in a semiarid climate

The aim of this study was to assess the magnitude of evaporation loss from the agricultural water reservoirs (AWRs) for irrigation at a regional scale and to analyze its impact on water storage efficiency. To this end, we identified the extant AWRs for irrigation in the Segura River Basin (SRB) in southeastern Spain, and calculated the water loss from each AWR per month and year. In order to accomplish this, we determined the monthly and yearly values of the pan coefficient, K_p, taking into account the geometric dimensions (area and depth) of the AWRs and local climate conditions through a function of air vapour pressure deficit (VPD). AWR areas were identified by interpreting aerial images, while climate conditions were assessed using daily meteorological data obtained from 74 automated agro-meteorological stations located in irrigated areas. Regional evaporation losses were estimated using aggregation GIS techniques. A total of 14,145 AWRs covering 4901 ha were identified, which represents 0.26 and 1.81% of the total area of SRB and the irrigated land, respectively. Results indicated that annual water loss at a basin scale reaches 58.5 × 10⁶ m³, which corresponds to 1.404 m of water depth over the flooded area and to 8.3% of irrigation water use in the basin. This quantity is higher than the industrial demand and similar to the environmental demand, and is equivalent to 27% of the domestic water use in a region with approximately two million inhabitants. The method used, based on annual K_p, appears the most straightforward to assess regional evaporative losses from AWRs, and can be extended to other regions and climates, provided that the VPD-dependent function that gives the pan coefficient is available.     

Intracerebroventricular Administration of Soy Protein Hydrolysates Reduces Body Weight without Affecting Food Intake in Rats

Some studies suggest that increased consumption of soy protein hydrolysates may cause body weight loss but the mechanism of action is unknown. The objective of this investigation was to determine whether intracerebroventricular (i.c.v.) infusion of soy protein hydrolysates decrease food intake and body weight. Adult male Sprague Dawley rats (n = 24) received i.c.v. injections of soy hydrolysate I (SH I) or soy hydrolysate II (SH II) three times weekly for 2 weeks. Krebs solution and leptin were used as negative and positive controls respectively. SH I (6.5–20 kDa with a strong band at 14 kDa) was produced by hydrolysis with alcalase, and SH II (∼2 kDa) was obtained by hydrolysis and ultrafiltration. Leptin successfully reduced body weight (−1.60 g) 24 h (p = 0.0093) after the third injection. SH I caused significant (p = 0.0009) decreases in body weight (−1.70 g) 24 h after the third injection but not after 48 h. SH II showed a tendency to prevent body weight gain but this effect was short of statistical significance (p < 0.40). Food intake was not affected by any of the soy hydrolysate treatments but leptin injection did cause significant decreases in food intake (p < 0.05). Data suggest that soy alcalase hydrolysate can decrease, in the short term, the rate of body weight gain independently of food consumption. This preliminary data show that soy peptides may play a role on body weight regulation, possibly by increasing energy utilization.     

Influence of alternative liquid chromatography techniques on the chemical complexity and bioactivity of isolated proanthocyanidin mixtures

Extracts rich in proanthocyanidins, which are implicated in multiple human health benefits, were comparatively separated using alternative separation methods [vacuum or open column liquid chromatography], separation matrices [Toyopearl, Sephadex, or silica gel], and degrees of subfractionation [8 or 12 subfraction series], to evaluate the influence of separation technique on the resolution of the chemical composition and the biological activity of separated proanthocyanidin mixtures in individual subfractions. Bioactivity was assessed using a DNA human topoisomerase II bioassay and structural composition by acid thiolysis (average degree of polymerization, DP) and HPLC-ESI/MS. The amount of parent fraction needed to inhibit 50% of topoisomerase II was 3.38 ng/mL with an average DP of 25.5. A 2(3) factorial analysis revealed that the vacuum and open column strategies for separation, when individually considered, did not yield significantly different results in terms of mass recovery, DP, or bioactivity; however, interactions with other factors such as matrix or subfraction series resulted in distinctive shifts in fraction profiles and biological activity. In general, Sephadex as a matrix permitted elution and separation of discrete, polymerized subfractions with potent inhibition against human topoisomerase II. Sephadex vacuum chromatography, Toyopearl open column chromatography, and Toyopearl vacuum chromatography separation techniques eluted highly polymerized proanthocyanidin mixtures, but the inhibitory bioactivity was attenuated as compared to the parent fraction, whereas Sephadex open column chromatography eluted highly polymerized subfraction mixtures that retained bioactive potential.     

Beta-conglycinin embeds active peptides that inhibit lipid accumulation in 3T3-L1 adipocytes in vitro

Obesity is a worldwide health concern because it is a well-recognized predictor of premature mortality. The objective was to identify soybean varieties that have improved potential to inhibit fat accumulation in adipocytes by testing the effects of soy hydrolysates having a range of protein subunit compositions on lipid accumulation and adiponectin expression in 3T3-L1 adipocytes. The results showed that differences in the protein distribution of 15 soy genotypes led to different potentials for the reduction of fat accumulation. The inhibition of lipid accumulation of soy alcalase hydrolysates in 3T3-L1 adipocytes ranged from 29 to 46%. Soy hydrolysates made from genotypes with 45.3 +/- 3.3% of total protein as beta-conglycinin, on average, showed significantly higher inhibition of lipid accumulation compared to those with 24.7 +/- 1.5% of extracted total protein as beta-conglycinin. Moreover, after in vitro simulated digestion with pepsin-pancreatin of the soy alcalase hydrolysates, 86% of the original activity remained. Adiponectin expression was induced in 3T3-L1 adipocytes treated with 15 soy hydrolysates up to 2.49- and 2.63-fold for high and low molecular weight adiponectin, respectively. The inhibition of lipid accumulation calculated from a partial least squares (PLS) analysis model correlated well with experimental data (R(2) = 0.91). In conclusion, it was feasible to differentiate soy varieties on the basis of the potential of their proteins to reduce fat accumulation using a statistical model and a cell-based assay in vitro. Furthermore, beta-conglycinin embeds more peptides than glycinin subunits that inhibit lipid accumulation and induce adiponectin in 3T3-L1 adipocytes. Therefore, soy ingredients containing beta-conglycinin may be important food components for the control of lipid accumulation in adipose tissue.     

Evolution of arsenate toxicity in nodulated white lupine in a long-term culture

White lupine is an As-resistant legume that is of interest for phytoremediation of As-contaminated soils. To achieve successful phytoremediation, monitoring of the nutritional status of the selected plant species during the entire culture cycle is required to maintain a plant cover with high biomass production. A long-term pot experiment was carried out with nodulated lupine grown on perlite with 10 and 100 microM As concentrations. The reproductive period (from 10 weeks) was the most sensitive phenologic stage of white lupine to long-term As exposure. The 10 microM As treatment increased the uptake and translocation of micronutrients, except for Cu, mainly at flowering with As levels in pods below the statutory limit (1 mg kg (-1) fresh weight). However, the 100 microM As treatment induced significant differences compared to the control. These findings confirm the relatively high resistance of white lupine to arsenate and support the use of this species in phytoremediation and/or revegetation of As-contaminated sites, with special attention on P and Cu nutrition at flowering.     

Alleviation of salt stress by arbuscular mycorrhizal in zucchini plants grown at low and high phosphorus concentration

With the aim of determining whether the arbuscular mycorrhizal (AM) inoculation would give an advantage to overcome salinity problems and if the phosphorus (P) concentration can profoundly influence zucchini (Cucurbita pepo L.) plant responses to AM, a greenhouse experiment was carried out with AM (+AM) and non-AM (−AM). Plants were grown in sand culture with two levels of salinity (1 and 35 mM NaCl, giving electrical conductivity values of 1.8 and 5.0 dS m⁻¹) and P (0.3 and 1 mM P) concentrations. The percentages of marketable yield and shoot biomass reduction caused by salinity were significantly lower in the plants grown at 0.3 mM P, compared to those grown at 1 mM P. However, even at high P concentration, the absolute value of yield and shoot biomass of +AM zucchini plants grown under saline conditions was higher than those grown at low P concentration. The +AM plants under saline conditions had higher leaf chlorophyll content and relative water content than −AM. Mycorrhizal zucchini plants grown under saline conditions had a higher concentration of K and lower Na concentration in leaf tissue compared to −AM plants. The P content of zucchini leaf tissue was similar for +AM and −AM treatments at both low and high P concentrations in the saline nutrient solution. The beneficial effects of AM on zucchini plants could be due to an improvement in water and nutritional status (high K and low Na accumulation).     

Gluten-Free Breads and Cookies of Raw and Popped Amaranth Flours with Attractive Technological and Nutritional Qualities

Gluten-free bakery foodstuffs are a challenge for technologists and nutritionists since alternative ingredients used in their formulations have poor functional and nutritional properties. Therefore, gluten-free bread and cookies using raw and popped amaranth, a grain with high quality nutrients and promising functional properties, were formulated looking for the best combinations. The best formulation for bread included 60–70% popped amaranth flour and 30–40% raw amaranth flour which produced loaves with homogeneous crumb and higher specific volume (3.5 ml/g) than with other gluten-free breads. The best cookies recipe had 20% of popped amaranth flour and 13% of whole-grain popped amaranth. The expansion factor was similar to starch-based controls and the hardness was similar (10.88 N) to other gluten-free cookies. Gluten content of the final products was around 12 ppm. The functionality of amaranth-based doughs was acceptable although hydrocolloids were not added and the final gluten-free products had a high nutritional value.     

Survival of Fusarium circinatum in soil and Pinus radiata needle and branch segments

Survival of Fusarium circinatum in colonized pine needles and wood pieces was measured. Naturally colonized branches and their needles were cut into small pieces and placed in mesh bags on the soil surface at two locations in northern Spain. Pieces were recovered periodically, cultured on a selective medium, and microscopically examined to identify the species. After 507 days, F. circinatum was recovered from 0 to 27% of the wood pieces and from none of the needles. After 858 days, F. circinatum was not recovered from any wood pieces but was found to be present on 1 out of 220 needle pieces analysed. Artificially infested pieces of wood and needles were placed on 5‐mm sieved soil either in plastic boxes at controlled temperature or in mesh bags under field conditions. No survival was recorded after 794 days under field conditions and the decline over time occurred more rapidly in inoculated pieces under field conditions. Soil was also infested with conidia of F. circinatum and survival was estimated. No conidia were recovered after 224 days at 30 °C, although at 20 and 5 °C the respective populations were 20 and 3700 cfu/g soil. Fusarium circinatum was not recovered from 2‐mm‐sieved soil collected under pitch canker‐infected pines. Results indicate that branch segments and needles naturally colonized by F. circinatum will not be a potential source of inoculum, and the fungus in soil is not likely to contribute to reinfection of new plantations after 2 years.