Changes in the Solubility of Corn Proteins through Interaction with the Arabinoxylans in Extruded Nixtamalized Corn Flour Treated with Xylanase

The extrusion process allows the production of nixtamalized corn flour rich in arabinoxylans, which help to prevent cardiovascular and intestinal diseases. During extrusion, physiochemical properties of nixtamalized corn flour are negatively modified. The use of enzymes such as xylanase in order to obtain nixtamalized corn flour using extrusion has been studied as an alternative to reduce these changes in corn flour tortilla. The aim of this research was to evaluate changes in protein solubility of extruded nixtamalized corn flour with and without different concentrations of xylanase enzyme (0.05, 0.075, and 0.1 %, w/w). Soluble proteins of each corn flour were extracted and analyzed by SE-HPLC, while insoluble proteins were determined by the combustion method. In addition, each corn flour was analyzed by scanning electron microscopy (SEM). Results showed that the extruded nixtamalized corn flour, with and without xylanase, increased the protein solubility, and this effect was lower in extruded nixtamalized corn flour with xylanase. Insoluble protein diminished in corn flours either with or without xylanase enzyme. The addition of xylanase reduces the effect that the extrusion process has on the solubility proteins of extruded nixtamalized corn flour.     

Spray-drying Microencapsulation of an Extract from Tilia tomentosa Moench Flowers: Physicochemical Characterization and in Vitro Intestinal Activity

Plant Foods for Human Nutrition - Silver linden (Tilia tomentosa Moench, TtM) flowers possess several health-promoting properties, especially at the neurological level, such as intestinal...     

Near and Mid Infrared Spectroscopy to Detect Malolactic Biotransformation of Oenococcus oeni in a Wine-Model

The aim of this work was to verify the potential of infrared （IR） spectroscopy in near and mid regions to detect the beginning of the malolactic fermentation （MLF） occurring in a model-wine and the further cells autolysis. MLF in wine is a secondary biotransformation due to lactic acid bacteria that usually occurs spontaneou,;ly or after starter inoculation at the end of alcoholic fermentation. Nowadays, it is desirable to supply winemakers with a new rapid and non-destructive approach to monitor MLF progress and 1R spectroscopy technology appears to be suitable for this purpose. The transformation of L-malic acid into L-lactic acid was carried out by inoculating a synthetic wine with an Oenococcus oeni culture and it was monitored through microbiological and chemical methods. At the same time, Fourier transform near infrared （FT-NIR） spectral data, in diffusive transflection mode using an optic probe, and FT-IR spectra, using an germanium crystal attenuated total reflectance （ATR） cell, were collected. Principal component analysis of the spectra was able to identify absorption bands related to the key molecular modifications that took place during the L-malic acid transformation. Thus, the samples were discriminated according to the fermentation phase. Although this study is a preliminary approach, results confirm that near infrared （NIR） and mid infrared （MIR） spectroscopy could be successfully applied to detect the start of MLF and the autolysis of the lactic acid bacteria （LAB） cells.     

Restoring silvopastures with oak saplings: effects of mulch and diameter class on survival,growth, and annual leaf-nutrient patterns

In Southwestern Spain, multifunctional silvopastoral systems consisting of pastureland and open oak woodlands are known as Dehesas. These, and other similar systems of the Mediterranean basin, are currently threatened by increasing intensive land use. As a consequence, oak regeneration is declining and is in need of adequate management and active restoration. Traditional restoration practices outplant one-year-old, nursery-produced oak seedlings grown in 250–350 cm³ containers, but establishment and growth results are typically poor. This work examines holm oak (Quercus ilex L. subsp. ballota (Desf.) Samp.) grown in a non-conventional container size (24 l) and age (6–7 years) with three mulch treatments (control, stone, and straw). In an open Dehesa of SE Spain, 106 oak saplings were planted in March 2010, and survival, diameter at breast height (DBH), and leaf-nutrient concentrations were analyzed. Forty months after planting, all treatments showed high survival (81 %) but only straw-mulched saplings differed significantly (94 %) from control (74 %). DBH increased over time but showed no significant differences among mulch treatments. Saplings with high initial DBH showed the greatest growth and change in DBH at the end of the study period. Leaf-nutrient concentrations changed significantly in the year following outplanting. Bi-monthly foliar nutrient concentration data show decreases in P, K, Zn, and B and sharp increases in Ca and Fe. In this work, we provide some evidence concerning the viability of non-conventional oak size for restoring, regenerating, or building up new agroforestry or silvopastoral systems. A combination of saplings with more than 10 mm of DBH and straw mulch is recommended.     

Effect of different methods for the induction of spermiation on semen quality in European eel

Five hormonal treatments with human chorionic gonadotropin (hCG) were tested for the induction of maturation and spermiation in male farmed eels. The main aim was to optimize previously used hormonal treatments to achieve shorter induction treatments, longer spermiation periods and/or higher sperm quality. Fish treated for just 3 weeks (treatment E) or until the onset of spermiation (treatment C) showed the worst results, while the treatment consisting of weekly administration of 1.5 IU hCG g^?1 fish (treatment A) induced the highest percentage of spermiating males, the highest number of sperm samples and sperm volumes and densities similar to the rest of the treatments (B: half hormone dosage, or D: biweekly administration). Evaluation of the sperm quality was performed by computer‐assisted sperm analysis (CASA), considering the percentage of total motile spermatozoa, the percentage of fast and medium‐velocity spermatozoa, as well as different motility parameters. Sperm samples from A‐D groups showed between 44% and 54% motile spermatozoa, and between 10% and 15% fast spermatozoa, while samples from E‐treated males showed 0% motile cells. No significant differences were found in the spermatozoa straight line velocity (VSL), curvilinear velocity (VCL) or the angular velocity (VAP), neither spermatozoa beating cross frequency (BCF) between A–D groups.     

The behavioural dynamics of fishers: management implications

In pursuing their livelihood, fishers develop strategies when faced with changes in regulations and other fishery conditions. Changes involve each individual in a decision‐making process governed by his/her own goals or constraints. Despite this reality, the complex dynamics of fishing has usually been ignored in designing management initiatives, which has contributed to management failures in many parts of the world. Fishers have generally been treated as fixed elements, with no consideration of individual attitudes based on their operating scales (geographical, ecological, social and economic) and personal goals. We review existing research on the social, economic and behavioural dynamics of fishing to provide insight into fisher behaviour and its implications for fisheries management. Emphasis is placed on fisher perception, and how fishers develop dynamic fishing tactics and strategies as an adaptive response to changes in resource abundance, environmental conditions and market or regulatory constraints. We conclude that knowledge of these dynamics is essential for effective management, and we discuss how such information can be collected, analysed and integrated into fisheries assessment and management. Particular emphasis is placed on small‐scale fisheries, but some examples from industrial fleets are provided to highlight similar issues in different types of fisheries.     

Cellulose acetate electrophoresis of canine plasma after fibrinogen precipitation by ethanol

Background: In routine canine medicine, anticoagulated blood is often the only sample sent to laboratories for diagnostic purposes. This hampers the interpretation of protein electrophoretic tracings because plasma contains fibrinogen, which migrates in the β–γ region. In human medicine, fibrinogen can be precipitated from plasma using ethanol. Objectives: The purpose of this study was to assess ethanol precipitation as a method for removing fibrinogen from canine plasma so as to facilitate the interpretation of electorphoresis results. Methods: Blood samples collected from 40 dogs were divided into plain tubes and tubes containing EDTA (n=20) or lithium–heparin (n=20). An aliquot of plasma from each sample was incubated with ethanol at a final concentration of 100 mL/L. Cellulose acetate electrophoresis was then performed on serum, plasma, and plasma treated with ethanol. To verify the efficiency of ethanol treatment, fibrinogen was added to 5 canine serum samples at final concentrations of 2.5, 5.0, and 10.0 g/L, and electrophoresis was performed before and after ethanol treatment. Results: Visual analysis of electrophoretograms from ethanol‐treated samples confirmed the disappearance of the fibrinogen peak from the β₂‐globulin region. Treatment with ethanol caused a significant decrease in the percentage of β₂‐globulins and a significant increase in the percentage of α₂‐globulins. Absolute values of most electrophoretic fractions were significantly decreased in ethanol‐treated plasma compared with serum. Conclusions: Ethanol treatment successfully removed fibrinogen from canine plasma and normalized electrophoretic profiles, but probably also precipitated proteins other than fibrinogen. Ethanol treatment is recommended to facilitate visual identification of abnormal monoclonal peaks, but not for determining absolute protein concentrations in electrophoretic fractions.     

Preliminary characterization and interaction of tubulin from Trichinella spiralis larvae with benzimidazole derivatives

Tubulin was estimated to account for 0.3% of the total soluble protein in Trichinella spiralis cytosolic fractions. Tubulin from T. spiralis was partially purified by precipitation with either taxol or vinblastine sulphate. Immunoblotting with alpha- and beta-tubulin monoclonal antibodies revealed the presence of tubulin in T. spiralis partially purified preparations. Electrophoretic mobility of T. spiralis tubulin in sodium dodecyl sulphate-polyacrylamide gels was very similar to that shown by pig brain tubulin. Further studies with colchicine binding assays indicated that T. spiralis tubulin has binding features similar to that of tubulin from other nematodes: colchicine association constant = 8.1 x 10(-4) M and competitive inhibition of colchicine binding by podophyllotoxin, with an inhibition constant of 1.3 x 10(-6) M. Finally, inhibition of colchicine binding by several benzimidazoles (mebendazole, fenbendazole, oxibendazole and albendazole) was investigated. All the benzimidazoles inhibited colchicine binding in a competitive manner, with inhibition constant values ranging from 1.4 x 10(-7) M (mebendazole) to 3.9 x 10(-6) M (fenbendazole).     

猪的回肠炎及其控制

猪的增生性回肠病 (回肠炎 )最早在 1 931年被发现 ,但直到约 60年后 ,本病的病原体由爱丁堡大学的 lawson等人命名为 lawsonia intracellu-laris。随后的 1 0年中由于许多特有技术的发展 ,使得人们可进一步研究这种细菌感染的流行病学和它的各种临床表现 -即地方性回肠炎 ( RI)、增生性肠病 ( PE)、坏死性肠炎 ( NE)和急性出血增生性肠病 ( AHPE)。所有疾病的控制方案都是以流行病学为基础的。有关病原体和传播方式的许多问题仍待解决。1　流行病学分子诊断技术可用于整个畜群抽查并可检测它们粪便中的 L intracellularis。西班牙对 7…