beta-glucans in promoting health: Prevention against mutation and cancer

The polysaccharides beta-glucans occur as a principal component of the cellular walls. Some microorganisms, such as yeast and mushrooms, and also cereals such as oats and barley, are of economic interest because they contain large amounts of beta-glucans. These substances stimulate the immune system, modulating humoral and cellular immunity, and thereby have beneficial effect in fighting infections (bacterial, viral, fungal and parasitic). beta-Glucans also exhibit hypocholesterolemic and anticoagulant properties. Recently, they have been demonstrated to be anti-cytotoxic, antimutagenic and anti-tumorogenic, making them promising candidate as pharmacological promoters of health. (C) 2008 Elsevier B.V. All rights reserved.

Efeito da presença das plantas daninhas no microclima da cultura da cevada

Um experimento foi realizado com cevada (Hordeum vulgare L.) em condições de campo, com o objetivo de avaliar , durante um período de estiagem (82 e 89 dia após a emergência da cevada), o microclima formado pela cultura mantida na presença ou ausência de plantas daninhas desde o início do ciclo. Foram avaliados o teor de água do solo, umidade relativa, temperatura, tensão de vapor d'água, déficit de saturação de vapor d'água, potencial água e teor de água do ar nos períodos da s 8: 30 às 9:00, 11:30 às 12:00, 14:30 às 15:00 e 17:30 às 18:00 horas a 0,0m, 0,10m, 0,20m, 0,30m, 0,40m, 0,50m, 0,60m e 0,70m de altura na entrelinha da cultura. A presença das plantas daninhas na cultura durante o período de estiagem contribuiu para reduzir as perdas de água do solo para a atmosfera. Nos três primeiros períodos do dia e nas áreas mais próximas do solo, a cultura mantida no mato os menores valores de temperatura e déficit de saturação de vapor d'água do ar, e os maiores valores de umidade relativa, tensão de vapor d'água, potencial água e teor de água do ar, que proporcionaram redução do consumo de água do solo.

Efeitos da cultura da cevada e de períodos de controle sobre o crescimento e produção de sementes de Raphanus sativus L.

Este experimento teve por objetivo avaliar os efeitos da cultura da cevada e de períodos de controle das plantas daninhas sobre o crescimento e produção de sementes de Raphanus sativus. Foram considerados dois tratamentos testemunha sem controle das plantas daninhas, com e sem a cultura. Nos oito demais tratamentos, a cultura esteve sempre presente, controlando-se as plantas daninhas até 10, 20, 30, 40, 50, 60, 80 e 100 dias após a emergência da cevada. A comunidade infestante da área era composta quase exclusivamente por R. .sativus. Avaliou-se o número de plantas, acúmulos de matéria seca, número médio de frutos e sementes de nabiça por planta e por unidade de área ; foram ainda avaliados o número médio de sementes por fruto, peso médio de 1.000 sementes e a contribuição das sementes na composição da matéria se catota. A análise dos resultados evidenciou que a espécie Raphanus sativus apresenta elevado potencial reprodutivo, sendo possível concluir pela ineficiência de programas de controle de curta duração, em termos de redução do banco de sementes. A presença da cultura da cevada reduziu tanto o crescimento quanto o número de sementes produzidas pela nabiça (R. sativus). Na ausência da cultura e de práticas de controle foram produzidas 5.074 sementes/m, a partir de 125 plantas/m ainda presentes na colheita da cultura.

Efeitos de potenciais de água no solo, em diferentes estádios fenológicos da cultura da cevada (Hordeum vulgare L.)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Prospecting sugarcane genes involved in aluminum tolerance

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

Increased production of beta-1,3 glucanase and proteins in Bipolaris sorokiniana pathosystem treated using commercial xanthan gum

Barley plants (cultivars Embrapa 127, 128 and 129) treated with xanthan gum, and with different time intervals between the administration of the inducer and the pathogen, demonstrated induction of resistance against Bipolaris sorokiniana. Induction was shown to have local and systemic action. In order to prove the resistance effect, biochemical analyses were performed to quantify proteins and the enzymatic activity of beta-1,3 glucanase. Results demonstrated that barley plants treated with the inducer, showed an increase in the concentration of proteins, as well as in the activity of the enzyme beta-1,3 glucanase, when compared with the extract from healthy plants. In infected plants, protein concentrations decreased and enzymatic activity was lower than in healthy plants. Results suggest that barley plants treated with xanthan gum developed mechanisms responsible for induced resistance, which are still unknown. The most important macromolecule in the defense mechanism was demonstrated to be PR-protein, due to its accumulation and concentration of proteins. However, it may not be the only macromolecule responsible for the resistance effect. (C) 2004 Elsevier SAS. All rights reserved.

Molecular genetic maps of the group 6 chromosomes of hexaploid wheat (Triticum aestivum L. em. Thell.)

Restriction fragment length polymorphism (RFLP) maps of chromosomes 6A, 6B, and 6D of hexaploid wheat (Triticum aestivum L. em. Thell.) have been produced. They were constructed using a population of F 7-8 recombinant inbred lines derived from a synthetic wheat X bread wheat cross. The maps consist of 74 markers assigned to map positions at a LOD ≥ 3 (29 markers assigned to 6A, 24 to 6B, and 21 to 6D) and 2 markers assigned to 6D ordered at a LOD of 2.7. Another 78 markers were assigned to intervals on the maps. The maps of 6A, 6B, and 6D span 178, 132, and 206 cM, respectively. Twenty-one clones detected orthologous loci in two homoeologues and 3 detected an orthologous locus in each chromosome. Orthologous loci are located at intervals of from 1.5 to 26 cM throughout 70% of the length of the linkage maps. Within this portion of the maps, colinearity (homosequentiality) among the three homoeologues is strongly indicated. The remainder of the linkage maps consists of three segments ranging in length from 47 to 60 cM. Colinearity among these chromosomes and other Triticeae homoeologous group 6 chromosomes is indicated and a consensus RFLP map derived from maps of the homoeologous group 6 chromosomes of hexaploid wheat, tetraploid wheat, Triticum tauschii, and barley is presented.

Parâmetros fisiológicos de cultivares de cevada sob déficits hídricos

The objective of this study was to evaluate some physiological parameters in six barley cultivars (Borema, Lagoa, BRS-180, BRS-195, EMB-128 e BRS-225), under water stress in different crop phenological phases. The treatments were as follows: TI - pots constantly irrigated until harvest: T2: - water stress starting from 45 days after sowing (DAS) and T3 - water stress starting from 65 DAS. Leaf resistance to water vapor diffusion (Rs), relative water content (RWC), and leaf water potential (Ψ1) were used to evaluate drought tolerance. Pots were arranged in a randomized block design with four blocks, six barley cultivars, and three treatments, in a total of seventy two pots. The experiment was conducted from August to November 2005 in a polyethylene greenhouse located at the experimental area of Rural Engineering Department - FCA, UNESP - Botucatu - SP. The results showed that all barley cultivars presented some adaptation to water stress, but EMB-128 was the most likely and BRS-180 the least likely to be drought tolerant. The results revealed that only one drought cycle may increase tolerance to drought.

Development of starch biobased and biodegradable plastics for their use in trays for food-packaging

This research work develops new methods to produce biodegradable starch-based trays for the purpose of replacing expanded polystyrene in the food packaging market. The starch based biopolymers present several drawbacks like poor mechanical properties and very high density. In order to overcome these drawbacks two research lines have been set up: blending thermoplastic starch with biobased reinforcements from agricultural wastes like barley straw and grape wastes, and testing the foamability of these materials with a Microwave-foaming method.

Xylo-oligosaccharides from lignocellulosic materials: Chemical structure, health benefits and production by chemical and enzymatic hydrolysis

Currently, there is worldwide interest in the technological use of agro-industrial residues as a renewable source of food and biofuels. Lignocellulosic materials (LCMs) are a rich source of cellulose and hemicellulose. Hemicellulose is rich in xylan, a polysaccharide used to develop technology for producing alcohol, xylose, xylitol and xylo-oligosaccharides (XOSs). The XOSs are unusual oligosaccharides whose main constituent is xylose linked by β 1-4 bonds. The XOS applications described in this paper highlight that they are considered soluble dietary fibers that have prebiotic activity, favoring the improvement of bowel functions and immune function and having antimicrobial and other health benefits. These effects open a new perspective on potential applications for animal production and human consumption. The raw materials that are rich in hemicellulose include sugar cane bagasse, corncobs, rice husks, olive pits, barley straw, tobacco stalk, cotton stalk, sunflower stalk and wheat straw. The XOS-yielding treatments that have been studied include acid hydrolysis, alkaline hydrolysis, auto-hydrolysis and enzymatic hydrolysis, but the breaking of bonds present in these compounds is relatively difficult and costly, thus limiting the production of XOS. To obviate this limitation, a thorough evaluation of the most convenient methods and the opportunities for innovation in this area is needed. Another challenge is the screening and taxonomy of microorganisms that produce the xylanolytic complex and enzymes and reaction mechanisms involved. Among the standing out microorganisms involved in lignocellulose degradation are Trichoderma harzianum, Cellulosimicrobium cellulans, Penicillium janczewskii, Penicillium echinulatu, Trichoderma reesei and Aspergillus awamori. The enzyme complex predominantly comprises endoxylanase and enzymes that remove hemicellulose side groups such as the acetyl group. The complex has low β-xylosidase activities because β-xylosidase stimulates the production of xylose instead of XOS; xylose, in turn, inhibits the enzymes that produce XOS. The enzymatic conversion of xylan in XOS is the preferred route for the food industries because of problems associated with chemical technologies (e.g., acid hydrolysis) due to the release of toxic and undesired products, such as furfural. The improvement of the bioprocess for XOS production and its benefits for several applications are discussed in this study. © 2012 Elsevier Ltd.

Desempenho de cultivares transgênicas de soja em sucessão a culturas de inverno em semeadura direta

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Simulação do caminhamento de herbicidas em diferentes tipos e quantidades de palhadas utilizadas no sistema de plantio direto

Pós-graduação em Agronomia (Agricultura) - FCA

Desenvolvimento de produto panificável à base de produtos de mandioca visando os hipersensíveis ao glúten

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Períodos críticos de défices hídricos em cultivares de cevada (Hordeum vulgare L.)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Produção de celulases fúngicas por fermentação em estado sólido e submersa utilizando biomassa lignocelulósica

Pós-graduação em Microbiologia - IBILCE