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1.
Genetica ; 145(3): 259-268, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28314965

RESUMEN

Low falling number and discounting grain when it is downgraded in class are the consequences of excessive late-maturity α-amylase activity (LMAA) in bread wheat (Triticum aestivum L.). Grain expressing high LMAA produces poorer quality bread products. To effectively breed for low LMAA, it is necessary to understand what genes control it and how they are expressed, particularly when genotypes are grown in different environments. In this study, an International Collection (IC) of 18 spring wheat genotypes and another set of 15 spring wheat cultivars adapted to South Dakota (SD), USA were assessed to characterize the genetic component of LMAA over 5 and 13 environments, respectively. The data were analysed using a GGE model with a mixed linear model approach and stability analysis was presented using an AMMI bi-plot on R software. All estimated variance components and their proportions to the total phenotypic variance were highly significant for both sets of genotypes, which were validated by the AMMI model analysis. Broad-sense heritability for LMAA was higher in SD adapted cultivars (53%) compared to that in IC (49%). Significant genetic effects and stability analyses showed some genotypes, e.g. 'Lancer', 'Chester' and 'LoSprout' from IC, and 'Alsen', 'Traverse' and 'Forefront' from SD cultivars could be used as parents to develop new cultivars expressing low levels of LMAA. Stability analysis using an AMMI bi-plot revealed that 'Chester', 'Lancer' and 'Advance' were the most stable across environments, while in contrast, 'Kinsman', 'Lerma52' and 'Traverse' exhibited the lowest stability for LMAA across environments.


Asunto(s)
Interacción Gen-Ambiente , Genotipo , Modelos Genéticos , Proteínas de Plantas/genética , Triticum/genética , alfa-Amilasas/genética , Fitomejoramiento , Triticum/enzimología
2.
Genetica ; 143(6): 671-80, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26403988

RESUMEN

Elevated level of late maturity α-amylase activity (LMAA) can result in low falling number scores, reduced grain quality, and downgrade of wheat (Triticum aestivum L.) class. A mating population was developed by crossing parents with different levels of LMAA. The F2 and F3 hybrids and their parents were evaluated for LMAA, and data were analyzed using the R software package 'qgtools' integrated with an additive-dominance genetic model and a mixed linear model approach. Simulated results showed high testing powers for additive and additive × environment variances, and comparatively low powers for dominance and dominance × environment variances. All variance components and their proportions to the phenotypic variance for the parents and hybrids were significant except for the dominance × environment variance. The estimated narrow-sense heritability and broad-sense heritability for LMAA were 14 and 54%, respectively. High significant negative additive effects for parents suggest that spring wheat cultivars 'Lancer' and 'Chester' can serve as good general combiners, and that 'Kinsman' and 'Seri-82' had negative specific combining ability in some hybrids despite of their own significant positive additive effects, suggesting they can be used as parents to reduce LMAA levels. Seri-82 showed very good general combining ability effect when used as a male parent, indicating the importance of reciprocal effects. High significant negative dominance effects and high-parent heterosis for hybrids demonstrated that the specific hybrid combinations; Chester × Kinsman, 'Lerma52' × Lancer, Lerma52 × 'LoSprout' and 'Janz' × Seri-82 could be generated to produce cultivars with significantly reduced LMAA level.


Asunto(s)
Genes Dominantes , Vigor Híbrido/genética , Modelos Genéticos , Triticum/enzimología , alfa-Amilasas/genética , Cruzamientos Genéticos , Triticum/genética
3.
J Food Sci Technol ; 52(9): 5691-9, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26344982

RESUMEN

Wheat flour is used in most of breads because of its nutrient components and high availability, but different problems are associated with this flour, such as allergies and loss of nutrient components due to milling and refining. In this study, five flours were used (20 %) in combination with wheat flour (80 %).to produce traditional Iranian Barbari bread. These included amaranth, barley, DDGS, rye and oat. Compositional measurements of moisture, fat, fiber, protein and ash content were taken. Physical tests were done to understand the changes in color, thickness, and texture. Results showed that the gluten content of each flour had a significant effect on the texture and thickness of the bread. Bread made with rye flour had the highest L* and that made with oat flour had the highest a*. As for b*, the highest was for the bread made with DDGS. It was also determined that bread made with 20 % DDGS and 80 % wheat flour had the highest fiber and moisture content, while that made with amaranth had the highest ash content, and that with rye had the highest fat. Adding different flours to wheat changed the physical and chemical attributes of final producst significantly.

4.
J Food Sci Technol ; 52(8): 5243-9, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26243948

RESUMEN

Tortilla is the most popular type of bread both in South and Central America. Since the demand for this bread among different classes of society is significant, improving its nutrient content could be important. Distillers dried grains with solubles is good source of fiber and protein, and can be used in the fortification of tortilla. In this study, three levels of DDGS (0, 10 and 20 %) were substituted for wheat flour and the physical and chemical properties of the resulting products were evaluated. Results showed that for the 20 % DDGS level, minimum force was required to rupture the tortilla. The color of the tortillas substituted with 10 and 20 % DDGS were darker, being 64.11 and 59.99, respectively (P < 0.05). As for chemical properties, the samples fortified with 10 and 20 % DDGS had higher protein (9.35 and 10.78 % dried basis), fiber (2.21 and 2.33 % dried basis) and fat (23.60 and 24.65 % dried basis) values at P < 0.05. Thus, it appeared that using DDGS in wheat tortillas can improve some of the nutritional values such as protein and fiber as well as the textural properties of these breads. Further work should examine consumer acceptability of these products.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38532601

RESUMEN

AIM: This article describes the use of graphite(Gr) and boron carbide (B4C) as multiple nanoparticle reinforcements in LM25 aluminum alloy. Because boron carbide naturally absorbs neutron radiation, aluminium alloy reinforced with boron carbide metal matrix composite has gained interest in nuclear shielding applications. The primary goal of the endeavor is to create composite materials with high wear resistance, high microhardness, and high ultimate tensile strength for use in nuclear applications. BACKGROUND: Science and Technology have brought a vast change to human life. The human burden has been minimized by the use of innovation in developing new and innovative technologies. To improve the quality of human life, fresh, lightweight, and creative materials are being used, which play a vital role in science and technology and reduce the human workload. Composite materials made of metal are being used because they are lightweight. Neutron absorption, high ultimate strength, high wear resistance, high microhardness, high thermal and electrical conductivity, high vacuum environmental resistance, and low coefficient of thermal expansion under static and dynamic conditions are all demands for the hybrid metal matrix composites utilized in nuclear applications. OBJECTIVE: • Stir casting is used to create the novel LM 25 aluminum alloy/graphite and boron carbide hybrid nanocomposites. • The mechanical properties such as ultimate tensile strength, yield strength, percentage of elongation, microhardness, and wear behavior are calculated. • Three analyses are performed: microstructure, worn surface analysis, and fracture analysis of the tensile specimen. METHOD: • Stir casting process< • Tensile, Hardness, Wear Test • Materials Characterization - FESEM, Optical Microscopy, EDS< Results: The mechanical properties values are 308.76 MPa, 293.51 MPa, 7.8, 169.2 VHN, and 0.01854mm3/m intended for ultimate tensile strength, yield strength, percentage of elongation, microhardness, and wear behavior, respectively. This implies that the synthesized composite may be used in nuclear applications successfully. CONCLUSION: The subsequent explanation was drawn from this investigative work: • The LM 25/B4C/Gr hybrid nanocomposite was successfully manufactured by employing the stir casting technique. For nuclear shielding applications, these composites were prepared with three different weight percentages of nanoparticle reinforcements in 2,4,6% Boron carbide and constant 4 wt.% graphite. • The microhardness values of the three-hybrid nanocomposite fabricated castings were determined to be 143.4VHN, 156.7VHN, and 169.2VHN, respectively. • The hybrid nano composite's microstructure revealed that the underlying LM 25 aluminum alloy matrix's finegrained, evenly dispersed nanoparticles of graphite and boron carbide were present.

• The microtensile test was carried out and it was found that the ultimate tensile strength, yield strength and percentage of elongation values are 281.35MPa, 296.52MPa, 308.76MPa, 269.43, 274.69, 293.51 and 3.4, 5.7, 7.8 respectively.

• Deformation caused the hybrid LM 25/B4C/Gr nanocomposite to fracture in ductile mode. Dimples and cavities are seen in the fracture because of the nanoparticle reinforcements and the matrix's tight connection.

• The wear loss of nanocomposite based on the input parameter applied load, sliding velocity and sliding distance values are 0.02456, 0.02189, 0.01854, 0.02892, 0.02586, 0.02315 and 0.02682, 0.02254, 0.02015 mm3/m, respectively.

• The LM 25 alloy's elemental analysis displays the aluminum alloy phase as the largest peak and the remaining elements as smaller peaks; also, the spectral analysis reveals the presence of boron (B), graphite (C), silicon, and ferrous in the aluminum alloy LM 25.

• Through worn surface FESEM investigation, it was shown that under sliding and high load situations, debris, delamination, and groove develop. Further rupture, fine, and continuous grooves were seen when low stress and sliding circumstances were applied to the LM 25/B4C/Gr and stir cast specimen. This result implies the presence of mild adhesive and delamination wear processes.

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6.
Foods ; 12(15)2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37569086

RESUMEN

In response to the demand for healthier foods in the current market, this study aimed to develop a new bread product using a fermented food product (FFP), a plant-based product composed of soya flour, alfalfa meal, barley sprouts, and viable microorganisms that showed beneficial effects in previous studies. White bread products prepared with three different substitution levels (5, 10, and 15%) of FFP were evaluated for physical characteristics (loaf peak height, length, width), color indices (lightness, redness/greenness, yellowness/blueness), quality properties (loaf mass, volume, specific volume), protein content, crumb digital image analysis, and sensory characteristics. The results revealed that FFP significantly affected all studied parameters, and in most cases, there was a dose-response effect. FFP supplementation affected the nutritional profile and increased the protein content (p < 0.001). The sensory test indicated that consumer acceptance of the studied sensory attributes differed significantly between groups, and bread with high levels of FFP (10 and 15% FFP) was generally more poorly rated than the control (0%) and 5% FFP for most of the variables studied. Despite this, all groups received acceptable scores (overall liking score ≥ 5) from consumers. The sensory analysis concluded that there is a possible niche in the market for these improved versions of bread products.

7.
Nat Med ; 6(8): 898-903, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10932227

RESUMEN

The parasite Plasmodium berghei imports the enzyme delta-aminolevulinate dehydratase (ALAD), and perhaps the subsequent enzymes of the pathway from the host red blood cell to sustain heme synthesis. Here we have studied the mechanism of this import. A 65-kDa protein on the P. berghei membrane specifically bound to mouse red blood cell ALAD, and a 93-amino-acid fragment (ALAD-DeltaNC) of the host erythrocyte ALAD was able to compete with the full-length enzyme for binding to the P. berghei membrane. ALAD-DeltaNC was taken up by the infected red blood cell when added to a culture of P. falciparum and this led to a substantial decrease in ALAD protein and enzyme activity and, subsequently, heme synthesis in the parasite, resulting in its death.


Asunto(s)
Plasmodium berghei/enzimología , Porfobilinógeno Sintasa/metabolismo , Animales , Antimaláricos/farmacología , Transporte Biológico Activo , Membrana Celular/enzimología , Eritrocitos/enzimología , Eritrocitos/parasitología , Hemo/biosíntesis , Malaria/tratamiento farmacológico , Malaria/enzimología , Malaria/parasitología , Ratones , Ratones Endogámicos BALB C , Plasmodium berghei/efectos de los fármacos , Porfobilinógeno Sintasa/genética
8.
Food Sci Nutr ; 8(8): 3999-4008, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32884681

RESUMEN

Chinese steamed bread (CSB) accounts for 30% of the wheat end-use in China. CSB was studied as a platform for fiber and protein enrichment, employing corn distillers dried grains. Food grade distiller's grain (FDDG) processed from co-products from the corn ethanol industry was used as the enrichment ingredient. Since CSB uses a lean formula with little or no added sugar or fat, it relies entirely on fermentation and steaming for flavor and texture development. FDDG was used to replace 0%-25% all-purpose flour (APF) in CSB formulations. Effects of FDDG on dough properties and quality of CSB were evaluated by instrumental (Farinograph, Mixolab, and Texture Analyzer), nutritional, and sensory methods. Protein and dietary fiber contents showed significant increases to 18.8% and 15.3%, respectively, for 100 g of steamed bread (25% FDDG db). Fiber in 100 g of fresh FDDG CSB ranged from 2.8 to 7.7 g. FDDG fortified doughs demonstrated higher water absorption, while dough development time, dough stability, and dough extensibility decreased significantly with partial APF replacement. FDDG contributed to increased hardness and adhesiveness in the CSB. Crumb analysis revealed reduced number of gas cells at higher FDDG substitution. FDDG enrichment reduced brightness (L*) of flour blends and CSB. Rheological and sensory analysis showed an upper level of FDDG substitution of 15% was acceptable without detriment to dough functionality, texture, and taste.

9.
Trends Biochem Sci ; 14(12): 492-6, 1989 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2696180

RESUMEN

Haem has long been known as the prosthetic group of haemoproteins such as haemoglobin, catalase and the cytochromes. Its biosynthesis is regulated by feedback mechanisms that ensure its adequate production but prevent its overaccumulation, which is highly deleterious as diseases such as porphyrias attest. However, recent years have seen rapid strides in our understanding of how haem (or more accurately haemin, its oxidized form) itself acts as an intracellular regulator of a variety of other metabolic pathways for systems that utilize oxygen.


Asunto(s)
Regulación de la Expresión Génica , Hemo/genética , Animales , Transporte Biológico , Hemo/biosíntesis , Biosíntesis de Proteínas , Transcripción Genética
10.
Foods ; 7(3)2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29494562

RESUMEN

Bread is one of the oldest foods known throughout history and even though it is one of the principal types of staple around the world, it usually lacks enough nutrients, including protein and fiber. As such, fortification is one of the best solutions to overcome this problem. Thus, the objective this study was to examine the effect of three levels of distillers dried grains with solubles (DDGS) (0%, 10% and 20%) in conjunction with three levels of SSL (sodium stearoyl lactate) (0%, 2% and 5%) on physical and chemical properties of Barbari bread (traditional Iranian bread). To the best of our knowledge, this is the first study to evaluate DDGS and Sodium Stearoyl-2-Lactilate (SSL), as sources of fortification in Barbari bread. The results showed that incorporation of 20% of DDGS and 0% SSL caused a significant increase in the amount of fiber and protein. As for the physical attributes, using higher amount of DDGS caused a darker color, and as for the texture parameters, the highest firmness was measured when 10% DDGS and 5% of SSL were used. Different Mixolab and Rapid Visco Analyzer (RVA) parameters also were measured with varying results. The findings of this study show that DDGS can be a valuable source of fiber and protein, which can be used as a cost effective source to fortify cereal-based products.

12.
Biochim Biophys Acta ; 607(2): 339-49, 1980 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-6445208

RESUMEN

The effects of the herbicide, 3-amino-1,2,4-triazole, an inhibitor of heme synthesis in rat liver, have been examined in the mold Neurospora crassa. The drug is a potent inhibitor of the growth of the mold and produces biochemical changes identical to those produced by chloramphenicol. 3-Amino-1,2,4-triazole, like chloramphenicol, is a direct and specific inhibitor of protein synthesis on mitoribosomes. A decrease in the levels of mitochondrial proteins which are completely or partly made on mitoribosomes and an accumulation in the levels of mitochondrial proteins of cytosolic origin have been observed. Both drugs depress porphyrin and heme levels, but there is actually an elevation in the levels of delta-aminolevulinate dehydratase, the rate-limiting enzyme of the heme-biosynthetic pathway in Neurospora crassa. In liver the enzyme is present in non-limiting amounts and the levels are depressed under conditions of 3-amino-1,2,4-triazole treatment. In Neurospora crassa the "derepression" of delta-aminolevulinate dehydratase under conditions of 3-amino-1,2,4-triazole or chloramphenicol treatment is only partial because the drugs inhibit protein synthesis on mitoribosomes. It is concluded that an optimal rate of protein synthesis on mitoribosomes is necessary to maintain an adequate rate of heme synthesis.


Asunto(s)
Amitrol (Herbicida)/farmacología , Proteínas Fúngicas/biosíntesis , Mitocondrias/metabolismo , Neurospora crassa/metabolismo , Neurospora/metabolismo , Ribosomas/metabolismo , Triazoles/farmacología , Cloranfenicol/farmacología , Hemo/biosíntesis , Neurospora crassa/efectos de los fármacos
13.
Gene ; 67(1): 125-30, 1988 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-2843434

RESUMEN

The biogenesis of eukaryotic cytochrome c oxidase involves the coordinate expression of nuclear and mitochondrial genes. Very little information is available on the gene structure of nuclear-coded cytochrome c oxidase subunits in mammalian systems. We report here the isolation and complete nucleotide sequence determination of a processed pseudogene for cytochrome c oxidase subunit VIc from rat liver. The pseudogene lacks introns and the coding region is intact with no deleterious lesions; however, there are 7 amino acid (aa) differences when compared to the sequence derived from cDNA clones. The pseudogene has the potential to code for a protein of 76 aa, containing a putative 3 aa N-terminal presequence when compared to the mature bovine heart VIc subunit. Potential regulatory regions, including a TATA box, are present in the 5'-flanking region.


Asunto(s)
Complejo IV de Transporte de Electrones/genética , Hígado/enzimología , Seudogenes , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Enzimas de Restricción del ADN , Genes , Sustancias Macromoleculares , Datos de Secuencia Molecular , Ratas
14.
Gene ; 190(1): 217-21, 1997 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-9185870

RESUMEN

Perfusion of liver with plasmid DNA-lipofectin complexes via the portal vein results in efficient accumulation of the vector in hepatocytes. Such hepatocytes, when administered intraperitoneally into a hepatectomized rat, repopulate the liver and express the transgene efficiently. This procedure obviates the need for large-scale hepatocyte culture for ex vivo gene transfer. Further, intraperitoneal transplantation is a simple and cost-effective strategy of introducing genetically modified hepatocytes into liver. Thus, in situ lipofection of liver and intraperitoneal transfer of hepatocytes can be developed into a novel method of non-viral ex vivo gene transfer technique that has applications in the treatment of metabolic disorders of liver and hepatic gene therapy.


Asunto(s)
Trasplante de Células , Hígado/metabolismo , Transfección/métodos , Animales , Femenino , Expresión Génica , Hepatectomía , Hígado/citología , Regeneración Hepática , Ratones , Peritoneo , Embarazo , Ratas , Transgenes
15.
Am J Trop Med Hyg ; 70(3): 256-9, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15031513

RESUMEN

The Plasmodium falciparum chloroquine resistance transporter (Pfcrt) K76T mutation and haplotype (amino acids 72-76) and the P. falciparum multidrug resistance 1 (Pfmdr1) mutation (N86Y) were analyzed as markers of chloroquine resistance in the DNAs of 73 blood samples from patients with P. falciparum malaria in India. Seventy of the 73 DNAs had the Pfcrt K76T mutation. Of these, 66 had the SVMNT haplotype and four had CVIET, the African/Southeast Asian haplotype. Only 20 of 69 DNAs had the Pfmdr1 N86Y mutation. It is surprising that the Pfcrt haplotype in India is predominantly SVMNT, rather than that seen in Southeast Asia. The widespread prevalence of the Pfcrt K76T mutation is a cause for concern.


Asunto(s)
Cloroquina/farmacología , Haplotipos , Malaria Falciparum/tratamiento farmacológico , Proteínas de la Membrana/genética , Plasmodium falciparum/genética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Animales , Resistencia a Medicamentos/genética , Humanos , Proteínas de Transporte de Membrana , Plasmodium falciparum/efectos de los fármacos , Proteínas Protozoarias
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