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11.
Juan de Dios Figueroa José Juan Véles Medina Martín Adelaido Hernández Landaverde Flavio Aragón Cuevas Marcela Gaytán Martínez Ezequiel Chávez Martínez Natalia Palacios Martha Willcox 《Journal of Cereal Science》2013
Eleven maize landraces were evaluated for pozole quality. The microstructural, thermal and rheological properties of annealed starch granules determine most of the quality of pozole. Annealed starch in traditional nixtamalisation has an important role in increasing gelatinisation onset (To), peak (Tp) and final (Tf) temperatures; peak, setback and final viscosity as well as the stability of the starch granule, all of which significantly affect pozole quality. Annealed starch in Cacahuacintle nixtamal (pozole end-use) increased temperatures To, Tp and Tf by >5.2, >3.8 and >4.1 °C respectively, and narrowed the range Tf − To from 13.78 to 12.62 °C. The enthalpy was reduced from 6.76 to 5.85 J/g, while the nixtamal starch in tortilla maize landraces presented fewer annealing effects. The annealing effect in nixtamal starch seems to stabilize the starch granules and avoid their collapse, compared to native starch, as shown by the X-ray diffraction peak intensity and pattern that is similar to unprocessed maize. Starch in nixtamal changes from Type A to Type V pattern in pozole. Kernel physical parameters, although important, affected the quality to a lesser extent, with the exception of the flotation index. Cacahuacintle maize landrace showed the best quality and yield as well as a short pozole cooking time. 相似文献
12.
Maia Fradkin María Rosa Ferrari Víctor Ferreira Ezequiel Martín Grassi Eduardo José Greizerstein Lidia Poggio 《Genetic Resources and Crop Evolution》2012,59(2):231-237
Triticum–Thinopyrum amphiploids arose from the need to obtain forage grasses highly resistant to pest, drought, soil salinity and frost and they
can be used as efficient bridges to transfer desired genes from wheatgrass species to wheat. One of them is trigopiro SH16
INTA, it was introduced in Argentina in 1947 but its genomic composition was unknown. The aim of this work was to determine
the chromosome number and genomic and chromosome composition of trigopiro SH16 INTA in order to use it in breeding programs.
The simultaneous use of the in situ hybridization technique with different probes (genomic DNA of Th. ponticum (Podp.) Barkworth et D.R. Dewey, pSc119.2 and pAs1) allowed us to conclude that the chromosome number of trigopiro SH16 is
2n = 42 and the genome composition would be: 14 chromosomes of the B genome, the 2D and 4D chromosome pairs of wheat, 14 chromosomes
of the J genome of Thinopyrum and the remaining chromosomes probably belong to the A genome of wheat. 相似文献
13.
Narambuena CF Ausar FS Bianco ID Beltramo DM Leiva EP 《Journal of agricultural and food chemistry》2005,53(2):459-463
Recently, it was found that the addition of chitosan, a cationic polymer, to whole or skim milk produces the destabilization and coagulation of casein micelles which takes place without modifications in the milk pH or in the stability of most of the whey proteins. In the present work, Monte Carlo simulations are employed to show that the phase separation of casein micelles induced by chitosan can be explained by a depletion mechanism, where an effective attraction between the casein micelles is induced by the presence of chitosan molecules. This interaction is described on the basis of Vrij's model, where the depletion of polymer from the gap between neighboring casein micelles originates an effective attractive interaction that leads to a phase transition. This model, that considers volume restriction effects, accounts for several qualitative and even quantitative aspects of the experimental data for the coagulation of casein through chitosan addition. 相似文献
14.
Ausar SF Bianco ID Castagna LF Alasino RV Narambuena CF Leiva EP Beltramo DM 《Journal of agricultural and food chemistry》2005,53(23):9031-9038
The cationic hydroxyethylcellulose Polyquaternium 10 (PQ10) was found to produce a dose-dependent destabilization of casein micelles from whole or skim milk without affecting the stability of most of the whey proteins. The anionic phosphate residues on caseins were not determinant in the observed interaction since the destabilization was also observed with dephosphorylated caseins to the same extent. However, the precipitation process was completely inhibited by rising NaCl concentration, indicating an important role of electrostatic interactions. Furthermore, the addition of 150 mM NaCl solubilized preformed PQ10-casein complexes, rendering a stable casein suspension without a disruption of the internal micellar structure as determined by dynamic light scattering. This casein preparation was found to contain most of the Ca2+ and only 10% of the lactose originally present in milk and remained as a stable suspension for at least 4 months at 4 degrees C. The final concentration of PQ10 determined both the size of the casein-polymer aggregates and the amount of milkfat that coprecipitates. The presence of PQ10 in the aggregates did not inhibit the activity of rennet or gastrointestinal proteases and lipases, nor did it affect the growth of several fermentative bacteria. The cationic cellulose PQ10 may cause a reversible electrostatic precipitation of casein micelles without disrupting their internal structure. The reversibility of the interaction described opens the possibility of using this cationic polysaccharide to concentrate and resuspend casein micelles from whole or skim milk in the production of new fiber-enriched lactose-reduced calcium-caseinate dairy products. 相似文献
15.
Chemical tools have proven indispensable for studies in glycobiology. Synthetic oligosaccharides and glycoconjugates provide materials for correlating structure with function. Synthetic mimics of the complex assemblies found on cell surfaces can modulate cellular interactions and are under development as therapeutic agents. Small molecule inhibitors of carbohydrate biosynthetic and processing enzymes can block the assembly of specific oligosaccharide structures. Inhibitors of carbohydrate recognition and biosynthesis can reveal the biological functions of the carbohydrate epitope and its cognate receptors. Carbohydrate biosynthetic pathways are often amenable to interception with synthetic unnatural substrates. Such metabolic interference can block the expression of oligosaccharides or alter the structures of the sugars presented on cells. Collectively, these chemical approaches are contributing great insight into the myriad biological functions of oligosaccharides. 相似文献
16.
Chockpisit Channuntapipat Terry Bertozzi Margaret Sedgley 《The Journal of Horticultural Science and Biotechnology》2013,88(2):228-232
SummaryShoot tips of two almond scion cultivars, ‘Ne Plus Ultra’ and ‘Nonpareil 15-1’, and one almond/peach hybrid rootstock were successfully cryopreserved using a one-step vitrification technique. Three week old in vitro cultures were cold-hardened at 4°C on the multiplication medium (Murashige and Skoog for ‘Ne Plus Ultra’ and the hybrid rootstock; Almehdi and Parfitt for ‘Nonpareil 15-1’) for three weeks. Shoot tips, 2–2.5 mm long, were excised and precultured for 1 d at 4°C on the same basal medium, without plant growth regulators, supplemented with 0.7 M sucrose. After the preculture, the shoot tips were incubated in vitrification solution at 25°C for 45 min for the almond scion cultivars and 60 min for the hybrid rootstock, and then stored under liquid nitrogen (LN) for at least 3 d. After rapid thawing at 30°C, the shoot tips were washed with the appropriate liquid basal medium containing 1.0 M sucrose and then cultured on the same basal medium, solidified with agar, but excluding NH4NO3 or (NH4)2SO4. Shoot regeneration was usually observed within 2–3 weeks. Survival after LN, recorded as the percentage of shoot tips that produced at least one new shoot four weeks after thawing, was 87.5, 60.0 and 72.5% for ‘Ne Plus Ultra’, ‘Nonpareil 15–1’ and the hybrid rootstock respectively. The one-step vitrification method is a promising simple technique for cryopreserving almond scion and rootstock shoot tips from in vitro cultures. 相似文献
17.
Mahyar Mobasseri Majid Pedram Ebrahim Pourjam Terry Bertozzi 《European journal of plant pathology / European Foundation for Plant Pathology》2017,148(2):423-434
Anguina obesa n. sp., a new species of the genus, causing small seed galls inside the ovaries of foxtail weed plants (Alopecurus mysuroides Huds.) is described and illustrated based on its morphological and molecular characters. The new species is characterized by its 1516–2564 μm long obese females irregularly ventrally curved after fixation, having six lines in lateral fields, 6–9 μm long stylet with well-developed rounded knobs, constriction at junction of isthmus with the pharyngeal bulb, monodelphic-prodelphic female reproductive system, and conical, 60–80 μm long tail. Males of the new species are characterized with their slender 936–1420 μm long body, 25–30 μm long tylenchoid spicules, and bursa not reaching tail tip. Second stage juveniles of the new species were also common inside the galls and also recovered from soil in type locality. The new species is morphologically close to Anguina agropyronifloris, A. amsinckiae, A. paludicola and A. tumefaciens, but is more closely related to A. paludicola, from which it can be separated based on differences in morphological characters and internal transcribed spacer sequence. In Bayesian inference using sequences of the aforementioned genomic fragment, the new species formed a clade with A. agrostis, A. funesta, A. graminis, A. phalaridis and some unidentified isolates, with robust Bayesian posterior probability (BPP). The morphologically closest species, A. paludicola, occupied a separate position, outside of the clade containing the new species. The sequences of two other genomic fragments, 18S and 28S rDNA (D2/D3 region) were also made available for the new species. Morphological comparisons of the new species with the related species are discussed. 相似文献
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19.
Renaville R Van Eenaeme C Breier BH Vleurick L Bertozzi C Gengler N Hornick JL Parmentier I Istasse L Haezebroeck V Massart S Portetelle D 《Domestic animal endocrinology》2000,18(2):165-176
The objectives of this study were to evaluate the effect of feed restriction and re-alimentation on the onset of puberty and IGF status in peripubertal male calves and to compare the radioimmunoassay (RIA) and western ligand blotting (WLB) methods for bovine IGFBP-2. Twelve prepubertal 290 d-old Belgian Blue bulls (mean weight: +/- 290 kg) were randomly assigned in three groups: a control group (NG; n = 4) receiving a classic fattening diet to induce "normal" growth (1.48 kg/d), a feed restricted group (RG; n = 4) to obtain reduced growth (0.50 kg/d) and, a severely restricted group (SG; n = 4) to nearly stop growth (0.08 kg/d). The feed restriction period was maintained over a period of 114 d. After the period of differential feeding, all animals received the control feed regime over a period of 100 d. Blood samples were collected at fortnightly intervals. Circulating IGF-I was measured by RIA whereas plasma IGFBPs was evaluated by WLB; IGFBP-2 was additionally quantified by RIA procedure. At the beginning of the trial, IGF-I levels were low (<100 ng/ml) and similar in the three groups in accordance with prepubertal status. In the NG group, a progressive rise in IGF-I was observed from Day 42 to Day 142 whereas in the RG and SG groups, IGF-I levels did not change until the experimental restriction period ended. The delay of the rise in plasma IGF-I was longer for the SG group, IGF-I remained low until 2 wk after the end of the period of restricted feeding. Surprisingly, although differences were detected for IGF-I levels between the three groups, the IGFBP-2 and -3 data, evaluated by WLB could only discriminate between NG and SG group and not between NG and RG. However, by using a RIA method, an IGFBP-2 decrease was observed in the NG group coincident with increasing IGF-I levels. For both RG and SG groups, IGFBP-2 levels remained high throughout the feed restriction period whereas plasma IGFBP-2 levels declined upon feeding in both groups. During this feed restriction period, IGFBP-2 was significantly lower in NG than in RG or SG groups. Moreover, SG group animals had higher levels in plasma IGFBP-2 than RG animals. In conclusion, puberty is characterized by developmental changes in plasma IGF-I and IGFBPs that were altered by feed restriction. Moreover, RIA evaluation of plasma IGFBP-2 is able to better reflect group differences than WLB. 相似文献
20.
Miguel Mellado Ezequiel Del Angel Oscar Rebolloso Eduardo García 《Preventive veterinary medicine》1998,37(1-4):33-39
To determine whether kids born on open range (subjected to stress due to management practices) had lower IgG concentrations and a higher mortality risk than kids born in a pen, serum IgG concentrations in 63 one-day-old kids were determined. Median Serum IgG concentrations one day after birth tended to be lower (p=0.09) in surviving kids born in the open than that of surviving kids delivered in pen (115 vs. 1119 mg dl−1). However, survival risk (71 and 82% for kids born on the open range and pen, respectively; n=79) were not significantly affected by site of kidding. Median IgG concentration of surviving kids born on a pen was not significantly different (p=0.13) compared to non-surviving kids (1118 vs. 115 mg dl−1). No differences were detected in either median serum IgG levels or death rates between male and female kids. Kids with IgG concentrations <800 mg dl−1 showed lower survival risks than those with higher concentrations. We concluded that typical management practices of kids delivered on open range at a goat operation under extensive conditions in northern Mexico tended to reduced colostrally acquired serum immunoglobulin levels, but had no effect directly on mortality. 相似文献