Profiles of Lipid Components,Fatty Acid Compositions and Triacylglycerol Molecular Species of Adzuki Beans (<Emphasis Type="Italic">Vigna angularis</Emphasis>)

Fatty acid (FA) compositions and molecular species of triacylglycerols (TAG) isolated from total lipids extracted from adzuki beans (Vigna angularis) were determined with a combination of AgNO₃-TLC and GC, and were compared in relation to the content of endogenous antioxidants analyzed by HPLC. δ-Tocopherol was present in the highest concentration (53.7–89.3 mg/kg), and γ-tocopherol in small amounts (11.2–14.8 mg/kg). The main lipid components were phospholipids (72.2–73.4%) and TAG (20.6–21.9%), whilst other components were also present in minor proportions (0.1–3.4%). Eighteen different TAG molecular species were identified and quantified by successive applications of AgNO₃-TLC and GC. The main components were SMD (4.6–5.0%), S₂T (13.4–16.4%), SD₂ (11.8–14.3%), SMT (7.3–8.3%), SDT (9.9–10.6%), D₃ (6.9–7.9%), MT₂ (5.2–6.3%), D₂T (7.0–11.2%), DT₂ (7.4–7.6%) and T₃ (6.2–7.2%) (where S, M, D, and T denote a saturated FA, a monoene, a diene, and a triene, respectively). No marked difference (P > 0.05) in the molecular species composition could be observed among the five cultivars. The results could be useful to both consumers and producers for manufacturing traditional adzuki confectionaries in Japan and elsewhere.     

DETERMINATION OF CROSS-GRAIN PROPERTIES OF CLEARWOOD SAMPLES UNDER KILN-DRYING CONDITIONS AT TEMPERATURE UP TO 140° C

ABSTRACT

Small specimens of Pinus radiata have been tested to determine the creep strain that occurs during the kiln drying of boards. The samples have been tested over a range of temperatures from 20°C to 140°C. The samples, measuring 150 × 50 × 5 mm, were conditioned at various relative humidities in a pilot-plant kiln, in which the experiments at constant moisture content (MC) in the range of 5-20% MC were undertaken to eliminate mechano-sorptive strains. To determine the creep strain, the samples were brought to their equilibrium moisture content (EMC), then mechanically loaded under tension in the direction perpendicular to the grain. The strain was measured using small linear position sensors (LPS) which detect any elongation or shrinkage in the sample. The instantaneous compliance was measured within 60 sec of the application of the load (stress). The subsequent creep was monitored by the continued logging of strain data from the LPS units.

The results of these experiments are consistent with previous studies of Wu and Milota (1995) on Douglas-fir ( Pseudotsuga menziesii ). An increase in temperature or moisture content causes a rise in the creep straw while the sample is under tension. Values for the instantaneous compliance range from 1.7 × 10^?3 to 1.28 × 10^?7 MPa^?1 at temperatures between 20°C and 140°C and moisture content in the range of 5-20%. The rates of change of the creep strains are in the Order of magnitude 10^?7to10^?8s^?1 for these temperatures and moisture contents. The experimental data have been fitted to the constitutive equations of Wu and Miloia (1996) for Douglas-fir to give material parameters for the instantaneous and Creep strain components for Pinus radiata.     

石蒜总生物碱的提取及其对酒精发酵过程的抑制机理

基于对石蒜生物碱抑菌作用的研究,结合生物碱的药用价值,提出酒精发酵前提取生物碱的必要性。通过单因素试验探讨生物碱的提取方式和提取条件对生物碱提取率的影响,结果表明,提取剂为甲醇、料醇比1:15(g/mL)、提取温度60℃、提取时间1h、提取液pH11.0条件下,生物碱的提取量达28.70mg/g;进一步对含有生物碱和不含生物碱的两种石蒜原料进行酒精发酵过程比较,结果显示,石蒜生物碱对糖化酶活性和工业酒精酵母的生长均具有明显抑制作用,对α-淀粉酶则影响较小,初步揭示了石蒜生物碱对酒精发酵过程的抑制机理。     

The ruminal degradability of fibre explains part of the low nutritional value and reduced methanogenesis in highly tanniniferous tropical legumes

BACKGROUND: Limited forage quality and low methanogenesis from fermentation of tropical shrub legumes is often attributed to high contents of condensed tannins (CTs), but characteristics of the fibre may be important, too. Using the rumen‐simulation technique an attempt was made to separate the influence of tannins and fibre on ruminal digestion and methanogenesis. Legumes with CTs (Calliandra calothyrsus, Flemingia macrophylla) and plants free of CTs (Vigna unguiculata, Brachiaria humidicola) were used. To separate effects, either CTs were inactivated using polyethylene glycol or purified fibres free of CTs were obtained. In experiment 1, legumes replaced one third of grass in the diet and urea was supplemented. In experiment 2, only purified fibres and casein were incubated. RESULTS: Purified fibres had a different degradability (low in legumes with CTs). Lignin prevented mainly hemicellulose from being degraded while the extent of degradation of hemicellulose seemed to have determined methanogenesis. In the mixed diets these effects were small when the supply of N was sufficient. When CTs were inactivated, fibre degradation was still lower with Calliandra than with Vigna. CONCLUSION: Properties of fibre, especially lignification, of CT‐rich plants help to explain the low feeding value of such forages, but CTs represent the over‐riding factor. Copyright © 2008 Society of Chemical Industry     

Evaluating the Role of Cell Wall Material and Soluble Protein in the Functionality of Cowpea (Vigna unguiculata) Pastes

ABSTRACT: Wet-milling of soaked, decorticated cowpeas generated large amounts of coarse cell wall material (CWM) and soluble protein (SP). CWM with high water-holding and swelling capacities contributed to excellent paste hydration and flow properties; high SP and paste viscosity resulted in superior foaming characteristics. In hydrated cowpea meal, the presence of coarse cellular material adversely affected paste hydration and flow characteristics; low SP and viscosity resulted in poor foaming. Wet-milling of hydrated meal improved viscosity and functionality. Intense dry-milling increased SP but adversely affected paste viscosity and functionality.     

Differential attractiveness of induced odors emitted by eight maize varieties for the parasitoid cotesia marginiventris: is quality or quantity important?

Herbivore-induced plant volatiles can function as indirect defense signals that attract natural enemies of herbivores. Several parasitoids are known to exploit these plant-provided cues to locate their hosts. One such parasitoid is the generalist Cotesia marginiventris, which is, among others, attracted to maize volatiles induced by caterpillar damage. Maize plants can be induced to produce the same blend of attractive volatiles by treating them with regurgitant of Spodoptera species. We collected and analyzed the regurgitant-induced emissions of two plant species (cowpea and maize) and of eight Mexican maize varieties and found significant differences among their volatile emissions, both in terms of total quantity and the quality of the blends. In a Y-tube olfactometer, the odors of the same artificially induced plant species and Mexican varieties were offered in dual choice experiments to naïve mated females of C. marginiventris. Wasps preferred cowpea over maize odor and, in 3 of 12 combinations with the maize varieties, they showed a preference for the odors of one of the varieties. A comparison of the odor collection with results from the behavioral assays indicates that not only the quantity of the volatile emissions, but also the quality composition of the volatile blends is important for attraction of C. marginiventris. The results are discussed in the context of the possibility of breeding crop varieties that are particularly attractive to parasitoids.     

A Lumenal Loop Associated with Catalytic Asymmetry in Plant Vacuolar H+-Translocating Pyrophosphatase

Membrane-integral inorganic pyrophosphatases (mPPases) couple pyrophosphate hydrolysis with H⁺ and Na⁺ pumping in plants and microbes. mPPases are homodimeric transporters with two catalytic sites facing the cytoplasm and demonstrating highly different substrate-binding affinities and activities. The structural aspects of the functional asymmetry are still poorly understood because the structure of the physiologically relevant dimer form with only one active site occupied by the substrate is unknown. We addressed this issue by molecular dynamics (MD) simulations of the H⁺-transporting mPPase of Vigna radiata, starting from its crystal structure containing a close substrate analog (imidodiphosphate, IDP) in both active sites. The MD simulations revealed pre-existing subunit asymmetry, which increased upon IDP binding to one subunit and persisted in the fully occupied dimer. The most significant asymmetrical change caused by IDP binding is a ‘rigid body’-like displacement of the lumenal loop connecting α-helices 2 and 3 in the partner subunit and opening its exit channel for water. This highly conserved 14–19-residue loop is found only in plant vacuolar mPPases and may have a regulatory function, such as pH sensing in the vacuole. Our data define the structural link between the loop and active sites and are consistent with the published structural and functional data.     

Reproductive performance and population dynamics of cowpea aphid (Homoptera: Aphididae) on leaf extracts of resistant and susceptible cowpeas

Membrane feeding studies were conducted to determine the effects of raw juices and chemical extracts of leaves of aphid-resistant (ICV-12) and aphid-susceptible (ICV-1) cultivars of cowpea [Vigna unguiculata L. (Walp.)], on the survival, growth, and reproduction of cowpea aphidAphis craccivora Koch. Life table and demographic statistics of the cohort population and subsequent generations were estimated. Compared to ICV-1, the leaf juices and chemical extracts of ICV-12 exhibited significant (P<-0.05) adveres effects on aphid survival, growth, and reproduction. Raw leaf juice and ethyl acetate extract of ICV-12 in both water and sucrose significantly (P<-0.05) limited aphid performance. The adverse long-term effects were often more extreme than those resulting from a diet of distilled water alone. Methanol extract of ICV-12 showed an intermediate level of adverse effects on aphids, being generally less than that of ethyl acetate but greater than that of hexane. Compared to the other ICV-12 extracts, the hexane extracts in water or sucrose media did not significantly affect the aphid performance. Overall, it was determined that antibiosis was a governing modality of aphid-resistance in ICV-12. Postingestive intoxication was caused by foliage components of seedling plants of that cultivar.     

Emissions From Kiln Drying of Pinus radiata Timber: Analysis,Recovery, and Treatment

The effect of drying schedules was investigated on the volatile organic compounds (VOCs) emission from kiln drying of Pinus radiata timber. An enclosed drying system has been invented to recover the VOCs emission and the heat in the drying medium. A new technology, called TOCKDOST, was also developed for treatment of the emission condensate for safe discharge to the environment. The condensate had high chemical oxygen demand (COD) of 256–280 mg l^?1, high total organic carbon (TOC) of 56–69 mg l^?1, and low pH of about 3.7, and thus required treatment before being discharged to the environment. After numerous trials, it has been found that the most effective treatment was to use Fenton's reagent followed by activated carbon adsorption. With optimum treatment conditions, the average COD was reduced by 93%, TOC was reduced by 87%, and pH was increased to about 6.