Thermal study and physico-chemical characterization of some functional properties of guava seeds protein isolate (Psidium guajava)

The guava seed protein isolate ( PI) was obtained from the protein precipitation belonging to the class of the gluteline (Ip 4.5). The conditions for the preparation of the PI were determined by both the solubility curve and simultaneous thermogravimetry-differential thermal analysis (TG-DTA): pH 11.5, absence of NaCl and whiteners and T=( 25 +/- 3) degrees C. Under these conditions a yield of 77.0 +/- 0.4%, protein content of 94.2 +/- 0.3, ashes 0.50 +/- 0.05% and thermal stability, T= 200 degrees C, were obtained. The TG-DTA curves and the PI emulsification capacity study showed the presence of hydrophobic microdomains at pH 11.5 and 3.0 suggesting a random coil protein conformation and, to pH 10.0, an open protein conformation. The capacity of emulsification (CE), in the absence of NaCl, was verified for: 1 - pH 3.0 and 8.5, using the IP extracted at pH 10.0 and 11.5, CE >= 343 +/- 5 g of emulsified oil/g of protein; 2 - pH 6.60 just for the PI obtained at pH 11.5, CE >= 140 +/- 8 g of emulsified oil/g of protein.

Enhanced methionine levels and increased nutritive value of seeds of transgenic lupins (Lupinus angustifolius L.) expressing a sunflower seed albumin gene

With the aim of improving the nutritive value of an important grain legume crop, a chimeric gene specifying seed-specific expression of a sulfur-rich, sunflower seed albumin was stably transformed into narrow-leafed lupin (Lupinus angustifolius L.). Sunflower seed albumin accounted for 5% of extractable seed protein in a line containing a single tandem insertion of the transferred DNA. The transgenic seeds contained less sulfate and more total amino acid sulfur than the nontransgenic parent line. This was associated with a 94% increase in methionine content and a 12% reduction in cysteine content. There was no statistically significant change in other amino acids or in total nitrogen or total sulfur contents of the seeds. In feeding trials with rats, the transgenic seeds gave statistically significant increases in live weight gain, true protein digestibility, biological value, and net protein utilization, compared with wild-type seeds. These findings demonstrate the feasibility of using genetic engineering to improve the nutritive value of grain crops.

Biological Activity of Seed Proteins in Malesian Legumes

In a study of the effects on animals of seed protein extracts of 15 Malesian members of the Leguminosae (including 11 rain forest tree species), most of the taxa agglutinated red blood cells, induced mitosis, and inhibited amylases. These results are consistent with the hypothesis that these proteins interact with other organisms, most probably in defense mechanisms against predation by animals. The functions of these proteins are most profitably studied in rain forest environments where their activity is so marked, and where biological interactions are particularly important.

柠条种子蛋白，同工酶遗传分析与群体遗传结构

本文研究了毛乌素沙地6个不同生态环境的柠条群体和1个锡盟草原站的小叶锦鸡儿群体的同工酶和种子蛋白的遗传变异。利用Brown等(/975)同工酶遗传分析方法对同工酶和种子蛋白的多态性进行了遗传分析。运用Shannon信息指数和Nei指数分析测定了锦鸡儿群体的遗传结构。结果表明： (l) Brown同工酶遗传分析的方法适合于柠条同工酶的遗传分析。 （2用LAP酶对柠条群体进行了精细的遗传结构研究。结果表明毛乌素沙地柠条群体的异交性。GST=D．134，即大部分的变异存在于群体内部，小部分的变异存在于群体之间。柠条群体的繁育系统与水分胁迫有关。随着生境变旱，繁育系统有向近交变化的趋势。 (3) Brown同工酶遗传分析方法也可以运用于种子蛋白遗传分析，柠条种子蛋白各亚基的遗传是孟德尔方式。 (4)由种子蛋白变异所统计测定的柠条群体的遗传分化系数GST=0.l81(Nei指数)或0.179(Shannon指数，Kongkiatngam改进)。群体变异水平按表型多样性依次为人工毛条群体>锡盟群体>滩地群体>硬梁群体>软梁群体>丘下群体>丘上群体。按遗传多样性依次为人工毛条群体>软梁群体>锡盟群体>滩地群体和硬梁群体>丘上群体>丘下群体。群体间基因流水平Nm>/，遗传距离D<0．1。 还试验对玉兰、合欢、紫藤、绿豆几种植物种子蛋白变异的遗传分析。最后对同工酶，种子蛋白遗传分析和群体遗传结构进行了讨论并提出今后工作的一些建议。

华山松（Pinus armandi）地理变异的生态生理学研究

华山松(Pinus armandi)是我国西部高海拔温凉山区的主要树种，自然分布大约在北纬23° 30'-36°30'，东经88°50'-113°30'之间，横跨13个省（区）包括两个季风区，六个气候带。由于水平空间区域广阔，分布区中间地带又为川藏高原的高山峡谷区，群体疏散，基因的迁移和交流困难，致使南北群体出现深刻的遗传分化，并在形态上、生理上充分表达出来。研究结果表明: 1)华山松树高生长出现明显的地理渐变模式，在同一适宜的立地条件下，15年生的南方群体的树高会超出北方种源的2-3倍。针叶长度也同样具有明显的南北差异，南方群体较长。 2)地理因子相关分析表明纬度因子是主导因子，根据种源的地理坐标，利用中科院植物所植被数量生态学开放室有关数据库和生态信息系统(EIS)进行有关气候数据统计分析表明大多数环境气候因子主要是由纬度决定的。在环境因子当中，年平均温度和极端最低气温，在华山松地理变异过程中起主要作用。利用聚类分析方法，可把华山松大致分为南北两个地理型，正好与气候因子聚类而成的两个环境类型相对应，反映着两个自然地理区的自然生态因子的综合区别。 3)利用已有的幼林生长数据和我们在华山松进入杆材期(15年生)的树高调查结果，作相关分析，发现二者相关关系显著。因此，利用早期树高作生长预测在林木选育上是可行的。 4)根据六个种源测定结果，发现南方温暖湿润气候条件下华山松种子较大，种壳较薄，而北方种源种子相对较小，种皮要厚一些。 5)虽然种群之间中性盐及碱性溶液提取的种子蛋白含量差异明显，但没有地理变异趋势。分析多肽组成，中性盐溶种子蛋白也没有地理特征。但碱性溶液提取的种子蛋白多肽组成却有明显地域性。其中36KD多肽仅出现在北方种群中，南方种群则没发现有同样多肽。 6)西藏种源表现出了一种独特的生物学特性，其种子较大有南方种源特征，但种皮厚又带有北方种源的特点，除此之外，它的碱性溶液提取的种子蛋白中含有36KD多肽，因此它可能是南北两个类群中的中间类型。 7)用活体针叶作测材料时，没能检测出光谱特性的地理变异。但改用分离的叶绿体作试验材料，发现南方种群的光能吸收4阶导数光谱在680nm处的峰值较大，670nm峰值较小，而北方种群中出现了670nm峰值较大的类群，推测北方种群反应中心活力有下降趋势。另外，低温荧光发射光谱及低温荧光激发光谱也有明显的地域分化，表明体内色素状态有一定的地理变异。 8)时绿素a荧光诱导动力学测定表明，南方种群可变荧光(Fv/Fo)与光能转换效率(Fv/Fm)较高，北方种群则相对要小一些，与四阶导数吸收光谱测定结果吻合．利用饱和脉冲重复激发技术，发现光化学荧光淬灭(Qp)和非光化学荧光淬灭(Qn)在北方种群中较大，南方种群较小，其中，Qn变化非常明显，而Qp变化较小． 综合研究结果，除树高生长．针叶和种子形态外，36KD碱溶性种子蛋白多肽680nm处4阶导数吸收光谱峰值大小，可变荧光强度(Fv/Fo)光能转换效率(Fv/Fm)以及非化学荧光淬灭系数都带有明显的地理特征，与华山松生长和适应能力紧密相关，可作为生理指标应用于生态地理型的区分或华山松的早期选择。

Utilization of organic nitrogen by ectomycorrhizal fungi (Hebeloma spp.) of arctic and temperate origin

Arctic and temperate strains of Hebeloma spp. were grown in axenic culture on glutamic acid, alanine, lysine and NH4+ as sole sources of nitrogen (N), with excess carbon (C) or deficient C (supplied as glucose). Their ability to utilize seed protein as a natural N source was also assessed. All strains tested had the capacity to assimilate amino acids and generally utilized alanine and glutamic acid more readily than NH4+. Some strains were able to utilize amino C when starved of glucose C, and could mineralize amino-N to NH3-N. Arctic strains, in particular, appeared to be pre-adapted to the utilization of seed protein N and glutamic acid N, which is often liberated in high concentrations after soil freezing. The results are discussed in relation to their possible ecological importance.

Adubação nitrogenada no perfilhamento da aveia-preta em duas condições de fertilidade do solo

Para testar o efeito de seis doses de N (0, 20, 30, 40, 50 e 60 kg/ha) aplicadas em cobertura, no final do perfilhamento, sobre a produção e a qualidade das sementes de Avena strigosa Schreber cv. Comum, foi conduzido um trabalho, em condições de campo, em Terra Roxa Estruturada distrófica, textura argilosa, em duas glebas com diferentes condições de fertilidade de solo. A gleba de menor fertilidade (pousio) apresentava saturação de bases (V) de 35% e a de maior fertilidade (cultivo com batata), 49%; nesta aplicou-se calcário para elevar a V para 70%. Na semeadura, foram aplicados 20, 80 e 40 kg/ha de N, P2O5 e K2O, respectivamente. A adubação nitrogenada em cobertura não afetou nem os componentes da produção, nem a produtividade, nem a germinação das sementes, nos dois experimentos. em condições de maior fertilidade do solo, a dose de 60 kg/ha de N provocou aumento no acamamento das plantas e diminuição do peso hectolítrico. em condições de menor fertilidade de solo, a adubação nitrogenada ocasionou aumentos na produção de massa vegetativa seca da parte aérea, e quando na dose de 60 kg/ha, aumentou o teor de proteína das sementes.

Dano por embebição em sementes de soja em função do teor de água inicial, cultivar e local de produção

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Isolado protéico de farinha de semente de goiaba (Psidium guajava): caracterização de propriedades funcionais e térmicas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Modos de aplicação de zinco em milho e sorgo cultivados em Latossolo Vermelho distrófico

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Isolamento, fracionamento e caracterização parcial das proteínas de amêndoa de Baru (Dipteryx alata Vog.)

Pós-graduação em Alimentos e Nutrição - FCFAR

Presença de Salmonella spp. na cadeia produtiva da carne bovina: estudo das fonte de contaminação para novilhos criados sob confinamento experimental

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Emprego do extrato de Moringa (Moringa oleífera Lamarck) na clarificação do caldo de cana para produção de açúcar e etanol

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Uso de marcadores morfológicos, bioquímicos y moleculares SRAP para diferenciar variedades de Cynara cardunculus L. (Asteraceae)

Dentro del complejo primario de Cynara cardunculus L. se encuentran diversas variedades botánicas: var. scolymus (alcaucil), var. altilis (cardo cultivado) y var. sylvestris (cardo silvestre). A lo largo de la historia del mejoramiento, la caracterización de los materiales ha evolucionado desde el uso de caracteres morfológicos hasta los modernos análisis moleculares, pasando por los marcadores bioquímicos. El objetivo del presente trabajo fue comparar la utilidad de los marcadores morfológicos, bioquímicos y moleculares para la caracterización de materiales pertenecientes a tres variedades botánicas de Cynara cardunculus. Tres cultivares de la var. scolymus, dos de la var. altilis y dos de la var. sylvestris fueron caracterizadas por variables morfovegetativas, proteínas de reserva y por marcadores moleculares a través de la técnica SRAP. Estas metodologías permitieron discriminar dos grupos: uno incluyendo las variedades de cardo cultivado y silvestre, y el otro, las variedades del alcaucil. Los datos moleculares y morfológicos permitieron además diferenciar los cultivares evaluados de la var. scolymus. Se concluye que los marcadores analizados son útiles para la caracterización intravarietal e intervarietal en programas de mejoramiento.

Several Thaumatin-Like Proteins Bind to β-1,3-Glucans1

Pathogenesis-related proteins from intercellular fluid washings of stressed barley (Hordeum vulgare L.) leaves were analyzed to determine their binding to various water-insoluble polysaccharides. Three proteins (19, 16, and 15 kD) bound specifically to several water-insoluble β-1,3-glucans. Binding of the barley proteins to pachyman occurred quickly at 22°C at pH 5.0, even in the presence of 0.5 m NaCl, 0.2 m urea, and 1% (v/v) Triton X-100. Bound barley proteins were released by acidic treatments or by boiling in sodium dodecyl sulfate. Acid-released barley proteins could bind again specifically and singly to pachyman. Water-soluble laminarin and carboxymethyl-pachyman competed for the binding of the barley proteins to pachyman. The N-terminal sequence of the 19-kD barley β-1,3-glucan-binding protein showed near identity to the barley seed protein BP-R and high homology to other thaumatin-like (TL) permatins. The 16-kD barley protein was also homologous to TL proteins, whereas the 15-kD barley protein N-terminal sequence was identical to the pathogenesis-related Hv-1 TL protein. Antifungal barley protein BP-R and corn (Zea mays) zeamatin were isolated by binding to pachyman. Two extracellular proteins from stressed pea (Pisum sativum L.) also bound to pachyman and were homologous to TL proteins.