A oxidação é um método que visa a modificação do amido por agentes oxidantes diversos, introduzindo grupamentos funcionais e realizando cisão das ligações glicosídicas. Seus objetivos são reduzir a viscosidade do polissacarídeo, elevar a transparência da pasta e limitar sua retrogradação. O objetivo do presente estudo foi modificar os amidos de milho com diferentes teores de amilose e o amido de mandioca pelo tratamento com ozônio e também caracterizar as amostras oxidadas quanto às características moleculares, estruturais e funcionais, correlacionando-as entre si. O processo de oxidação foi efetivo em alterar diversas propriedades e funcionalidades dos amidos estudados, contudo de modos distintos para as diferentes fontes. Tais diferenças decorrem da composição e estrutura granular peculiares de cada um, promovendo diferentes taxas de degradação das lamelas amorfas e cristalinas e da presença de grupos carboxilas. A oxidação pelo ozônio nas condições estudadas reduziu a viscosidade apenas do amido de milho normal; no caso dos amidos de milho ceroso e de mandioca, a viscosidade foi ligeiramente aumentada. O amido de milho de alta amilose não apresentou viscosidade nas condições de analisadas pelo Rapid Visco Analyser, tanto antes como após a oxidação. O setback foi reduzido pelo processo oxidativo com o ozônio para os três amidos, tornando-os mais estáveis. A oxidação aumentou a claridade de pasta de todos os amidos. A ozonização também causou alterações no amido de milho ceroso e no de mandioca, de modo a proporcionar capacidade de expansão no forno, em índices próximos àqueles de amostras comerciais de polvilho azedo. Os demais amidos não se expandiram significativamente. A propriedade de expansão no forno foi afetada principalmente pela variação de entalpia de gelatinização dos amidos, mas também pelos teores de carboxilas e de carbonilas, fator de inchamento, quebra de viscosidade, setback, cristalinidade relativa e tamanho das cadeias ramificadas de amilopectina (cadeias B2 e B3 e tamanho médio). O uso do ozônio, portanto, poderá ser útil nesta modalidade de modificação dos amidos e, em especial para o amido de mandioca ou de milho ceroso, capacitando-os para a expansão no forno, o que poderia gerar produtos panificáveis mais padronizados do que os obtidos pelo polvilho azedo, ou sem as consequências da oxidação por métodos químicos mais agressivos, como o uso do hipoclorito de sódio. / Oxidation is a method which aims the starch modification by various oxidizing agents, introducing functional groups and performing the cleavage of glycosidic linkages. Its objectives are to reduce the polysaccharides viscosity, raising the transparency paste and minimizing retrogradation. The aim of this study was to modify the corn starch with different levels of amylose and the cassava starch using ozone and also to characterize the samples oxidized as the molecular, structural and functional characteristics, relating them with each other. The oxidation process was effective changing several properties and features of the studied starches, however, in different ways for the different sources. These differences come from having starches different composition and granular structure, providing different rates of degradation of amorphous and crystalline lamellae and the presence of carbonyl groups, and carboxyl formed. A reduction in viscosity was observed for the normal corn starch after oxidation, and an increase for the waxy maize and cassava starches. The high amylose corn starch showed no viscosity by Rapid Visco Analyser, before or after oxidation. The setback was reduced by the oxidation process with ozone for the three starches, rendering them more stable. Oxidation by ozone under the conditions studied increased paste clarity of all starches. Ozonation caused changes in the waxy corn and cassava starches, providing baking properties, in indices close to those of commercial samples of sour cassava starch. The other starches are not expanded significantly in the oven. The baking property was mostly affected by enthalpy of gelatinization of starches, but also by carboxyl and carbonyl contents, swelling factor, breakdown, setback, relative crystallinity and size of amylopectin branched chains (B2, B3 and medium size). So, the use of ozone may be useful in this starch modification modality, and in particular for cassava or waxy maize starches, enabling the expansion in oven, which could generate more standardized baking products than those obtained by sour cassava starch, or without consequences of oxidation using more aggressive chemical methods, such as sodium hypochlorite.

<p>It is well known that colonic microbiota is influenced by both intrinsic and extrinsic factors; out of all these, diet plays a major role. The traditional human diet has typically been high in overall dietary fiber intake, due its inherent presence in plant-derived foods. However, over the years, dietary patterns have transitioned into a low-fiber Westernized diet. This diet is increasingly implicated in colonic diseases. Dietary fiber consumption is known to increase microbial diversity, yet the mechanisms are still unclear. This is partially true because dietary fiber as a category is composed of a wide variety of structures, which may have divergent effects on the gut microbiome. The food industry has extracted, isolated, refined and purified non-digestible carbohydrates and, in some cases, modified them for improved function, which may influence their interaction with the gut microbiome. This study was developed in two phases: we first hypothesized that glucans produced by different processes were structurally distinct and that these fine structural differences in glucans would govern microbial responses to the polymers. To test this hypothesis, we first determined the structural characteristics of the glucans by gas chromatography and mass spectrometry, which revealed substantial structural differences among the glucans with respect to size and linkage patterns, consequently categorizing the glucans by structure (i.e., mixed linkage α-glucans, resistant maltodextrins, and polydextroses). The second study involved the <i>in vitro </i>fecal fermentation of these commercially available soluble glucans which are uniformly composed of glucose linked into different structural arrangements. We further hypothesized that each glucan would select for different microbiota and that there would be glucan-specific general responses across microbiomes. We were able to identify a variety of idiosyncratic metabolic patterns as well as differential organisms selecting for specific glucan structures. Although there were associations with glucan classes at the family level (e.g., <i>Bacteriodaceae </i>and <i>Lachnospiraceae </i>were discriminants of the resistant maltodextrins and polydextroses respectively), associations with glucans across individual species within these families varied. These findings suggest that microbiome responses to structurally distinct glucans depend upon both fine glucan structure and community context, and community metabolic phenotypes emerge from the interaction of the two. These findings are relevant to the food industry as they may enable optimization of synthesis to generate chemical structures that select for specific organisms and/or improve overall gut health.</p>

Toll-like receptors (TLRs) play important role in the innate immune system. TLR15 is reported to have a unique role in defense against pathogens, but its structural and evolution characterizations are still poorly understood. In this study, we identified 57 completed TLR15 genes from avian and reptilian genomes. TLR15 clustered into an individual clade and was closely related to family 1 on the phylogenetic tree. Unlike the TLRs in family 1 with the broken asparagine ladders in the middle, TLR15 ectodomain had an intact asparagine ladder that is critical to maintain the overall shape of ectodomain. The conservation analysis found that TLR15 ectodomain had a highly evolutionarily conserved region on the convex surface of LRR11 module, which is probably involved in TLR15 activation process. Furthermore, the protein-protein docking analysis indicated that TLR15 TIR domains have the potential to form homodimers, the predicted interaction interface of TIR dimer was formed mainly by residues from the BB-loops and αC-helixes. Although TLR15 mainly underwent purifying selection, we detected 27 sites under positive selection for TLR15, 24 of which are located on its ectodomain. Our observations suggest the structural features of TLR15 which may be relevant to its function, but which requires further experimental validation.

Toll-like receptors (TLRs) are important pattern recognition receptors in the innate immune system of fish. Although ten years have passed since the first identification, the systematic knowledge about fish-specific TLR19 is still far insufficient. In present study, a phylogenetic analysis showed that TLR19 belonged to family 11, and clustered with TLR20 and TLR11/12 on the evolutionary tree. TLR20 is the closest paralogue of TLR19. The ectodomain of TLR19 contains 24 leucine-rich repeat (LRR) modules. The electrostatic surface potential analysis indicated that the modeled structure of TLR19 ectodomain showed much stronger polarity on the ascending lateral surface than on the descending lateral surface. The ascending lateral surface with strong electrostatic surface potential possibly mainly participates in the ligand binding of TLR19 ectodomain. The quite small dN/dS value at the TLR19 locus showed that TLR19 was very conserved. Approximately one third codons in the coding sequence of TLR19 were subjected to significantly negative selection, whereas only 5 codons underwent significantly positive selection. Overall, these findings possibly help in deepening the understanding to fish-specific TLR19.

Toll-like receptors (TLRs) are critical components of the innate immune response of fish. In a phylogenetic analysis, TLR27 from three fish species, which belongs to TLR family 1, clustered with TLR14/18 and TLR25 on the evolutionary tree. The ectodomain of TLR27 is predicted to include 19 leucine-rich repeat (LRR) modules. Structural modeling showed that the TLR27 ectodomain can be divided into three distinctive sections. The lack of conserved asparagines on the concave surface of the central subdomain causes a structural transition in the middle of the ectodomain, forming a distinct hydrophobic pocket at the border between the central subdomain and the C-terminal subdomain. We infer that, like other functionally characterized TLRs in family 1, the hydrophobic pocket located between LRR11 and LRR12 participates in ligand recognition by TLR27. An evolutionary analysis showed that the dN/dS value at the TLR27 locus was very low. Approximately one quarter of the total number of TLR27 sites are under significant negatively selection pressure, whereas only two sites are under positive selection. Consequently, TLR27 is highly evolutionarily conserved and probably plays an extremely important role in the innate immune systems of fishes.

Background: During live concerts attendees are exposed to excessive high intensity sounds for durations considered dangerous to the auditory system. Thus, regular live music concert attendees are at risk for developing Music Induced Hearing Loss (MIHL) due to their recreational habits. Although MIHL is preventable, current hearing conservation is limited at live music venues. As personal hearing protection is poor within this community, a need for alternative hearing conservation strategies is evident. Method: The objectives of this multi-method quantitative research study was to determine whether venue-based hearing conservation strategies in live music venues are a plausible means of reducing the risk of music induced hearing loss. Four live rock and heavy metal music venues in Johannesburg (South Africa) were included in the study. The current venuebased hearing conservation strategies as well as the acoustic and structural characteristics of these venues are described. In addition, the Sound Pressure Levels (SPLs) were measured throughout the venues. The variance of the mean SPLs between different areas within these venues were then calculated and effects of the structural characteristics on the variance of the sound levels within the venues were determined. Results: The results indicated that hearing conservation including awareness programs and availability of Hearing Protection Devices (HPDs) are not currently occurring in the music venues. Music venues further do not comply with the OHSA (2003) regulations nor are they compliant in terms of the acoustic and structural recommendations for reducing the intensity levels in music venues. Statistical analysis indicated at least one pair of significant differences in the mean SPLs recorded in the different areas in each venue. Results further indicated trends in the variance of intensity levels between different areas confirming a positive relationship between each of these five trends and the variance of sound levels. Thus, this study indicates that venue-based hearing conservation strategies may be a plausible means for reducing the risk for MIHL in attendees at live music venues. Implications: Implications of this study are discussed in relation to clinical and practice guidelines for both audiologists, and occupational health personnel, whilst the need for changes in legislation are highlighted.

Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-10-18T12:35:34Z No. of bitstreams: 1 2016 - Tatiana Pires Pereira.pdf: 2546753 bytes, checksum: c1673b0ae2c6812a3f60faa79b5fae75 (MD5) / Made available in DSpace on 2017-10-18T12:35:34Z (GMT). No. of bitstreams: 1 2016 - Tatiana Pires Pereira.pdf: 2546753 bytes, checksum: c1673b0ae2c6812a3f60faa79b5fae75 (MD5) Previous issue date: 2016-07-27 / Funda??o Carlos Chagas Filho de Amparo ? Pesquisa do Estado do RJ - FAPERJ / This work was divided in four chapters, in which the first was performed with the goal of quantifying the condensed tannin (CT) content by the Stiasny?s reaction and to determine the classes of secondary metabolites present by the phytochemical prospection technique and magnetic resonance in the tropical forage legumes Cajanus cajan (guandu - GUA), Gliricidia sepium (gliricidia - GLI), Flemingia macrophylla (flemingia - FLE), Cratylia arg?ntea (cratilia - CRA), Mimosa caesalpineafolia (sabi?) (this legume divided into bark and leaf fraction ? SABc and SABf) among the treatments. The extracts obtained were divided into: total extract, number of Stiasny (NS), CT and non-tannins. The FLE, CRA, GUA,GLI, SABf and SABc had obtained the following values for total extract: 13.20; 13.06; 8.28; 14.73; 15.67 and 6.22%, respectively. The reactivity by NS, in the same order of legumes, was 11.25; 4.54; 7.37; 6.70; 23.06 and 71.62%, whereas the CT presented the following values: 1.52; 0.59; 0.61; 0.96; 3.6 and 4.43%, and non-tannin was 11.68; 12.46; 7.67; 13.75; 12.07 and 1.76%, respectively. The following classes of secondary metabolites were identified with greater evidence: saccharides, carbohydrates, non-protein amino acids and glicos?deos cardioativos. For the CT, the intensity was low for most of the legumes, with greater content in CRA, GUA and SABf. The wain compound in the extracts was methyl-inositol (sugar). The second chapter had the objective of assaying in the legumes mentioned above and one more specie, Stylosanthes spp. (estilosantes-EST), condensed tannin (CT) constituents, with the use of organic solvents, soluble CT (ECT), CT adhered to protein (PBCT), CT adhered to fiber (FBCT), and total CT (TCT), CT structural pro-pelargonidin (PP); prodelfinidin (PD) and procyanidin (PC), molecular weight (polymerization degree (DP), molecular distance distributed of the polymer (PDI); average weight of molecular mass (Mw), and average number of molecular mass (Mn), and the biological activity through precipitated proteins by phenols (PPP). The variables ECT, PBCT, and TCT presented were influenced by different species (P?0.05). The FBCT fraction was not found in the legumes. Molecular weights (DP, PDI, Mw e Mn) were affected by the different species (P?0.05), ranging from 737 to 1168 da. The structural characteristics (PP, PD, PC and PD:PC) varied among the species. In the third chapter I evaluated methanogenesis (total methane (CH4total)), incubated (CH4inc) and fermented (CH4ferm) and ruminal fermentation parameters total gas production (PGT), pH, ammonium (N-NH3), short-chain fatty acids (SCFA) and in vitro organic matter disappearance (IVOMD) as they related to CT present in the legumes and Urochloa brizantha cv. marandu hay as control (CTL). The effect of polyethylene glycol (PEG) on the leaf fraction of sabi? was tested as well, which had a CT content of 15.97%. No alteration in the pH (P?0.05) for the treatments evaluated. However, a decrease of total gas and methane production for all the treatments with presence of CT (P?0.05). When PEG was added, there was a 27.01 (8% PEG) and 35.01 (16% PEG) increase in total gas production and 3.59 (8% PEG) and 4.15 (16% PEG) of methane production. GUA, FLE, SABc and SABf were capable of modifying (P?0.05) the content of NH3-N (mg/dL), along with the CTL, which also presented lower values compared to legumes with no or only traces of CT (ETL, CRA and GLI). There was significant difference (P?0.05) for IVOMD between the legumes and control, it was observed lower disappearance (P?0.05) for FLE, GUA and SABf in relation to CTL, while SABc did disappear. The SABf IVOMD was affected by the addiction of PEG. There was lower digestibility for FLE, GUA and SABf in relation to the CTL, while the bark fraction of SAB did not disappear at all. On the SCFA profile, there was difference (P?0.05) among the treatments evaluated, with lower values for the legumes with presence of CT. In the fourth chapter I tested the effect of CT from the legumes in study (FLE, CRA, GUA, GLI, EST, SABf and SABc) on larval migration inhibition (LMI) in vitro, on the infective larvae L3 of the nematode Haemonchus contortus (HC), compared with Ivermectin and a negative control (rumen fluid and buffer). Among the legumes studied, SABf and GUA did not differ (P?0.05), with the greater (P?0.05) LMI percentage (34.75% and 34.33%) than the other entries. The legumes GUA, FLE and SABc did not differ (P?0.05), presenting moderate values of LMI (30.25%, 30.0% and 29.75%, respectively). Among the legumes studied, the lowest LMI percentage was CRA (18.46%), GLI (23.75%) and negative control (rumen fluid and buffer), with values near (P?0.05) from to Ivermectin (22.0%). / Este trabalho foi dividido em quatro cap?tulos. O primeiro realizou-se com o objetivo de quantificar o teor de tanino condensado (TC) atrav?s da Rea??o de Stiasny e conhecer as classes de metab?litos secund?rios presentes pela t?cnica de prospec??o fitoqu?mica e resson?ncia magn?tica nas leguminosas forrageiras tropicais Cajanus cajan (guandu-GUA), Gliricidia sepium (gliricidia-GLI), Flemingia macrophylla (flemingia-FLE), Cratylia arg?ntea (cratilia-CRA), Mimosa caesalpineafolia (sabi?) sendo que essa leguminosa tinha a fra??o casca e folha (SABc e SABf) entre os tratamentos. Os extratos obtidos foram divididos em: extrato total, n?mero de Stiasny (NS), TC e n?o taninos. A FLE, CRA, GUA, GLI, SABf e SABc apresentaram os valores para o extrato total 13,20; 13,06; 8,28; 14,73; 15,67 e 6,22%, respectivamente. A reatividade pelo NS, na mesma ordem das leguminosas, foi de 11,25; 4,54; 7,37; 6,70; 23,06 e 71,62%, j? o TC apresentou os seguintes valores 1,52; 0,59; 0,61; 0,96; 3,6 e 4,43% e o n?o tanino foi de 11,68; 12,46; 7,67; 13,75; 12,07 e 1,76%, respectivamente. Foram identificadas as seguintes classes de compostos secund?rios em maiores evid?ncias: os sacar?deos, carboidratos, amino?cidos n?o prot?icos e os glicos?deos cardioativos. J? para o TC, a intensidade foi baixa para grande parte das leguminosas, prevalecendo maior teor para CRA, GUA e SABf. Foi constatado como componente principal nos extratos o metil-inositol (a??car). O segundo cap?tulo teve como objetivo avaliar nas leguminosas citadas acima e mais uma esp?cie, o Stylosanthes spp (estilosantes-EST), analisar os constituintes do TC com uso de solvente org?nico, tanino sol?vel (TCE), tanino aderido ? prote?na (TCPB), tanino aderido ? fibra (TCFB) e taninos condensados totais (TCT), caracter?sticas estruturais tais como: propelargonidina (PP); prodelfinidina (PD) e procianidina (PC); peso molecular (grau de polimeriza??o?(DP); dist?ncia do peso molecular distribu?do do pol?mero (PDI); peso m?dio da massa molecular (Mw); n?mero m?dio da massa molecular (Mn); al?m de determinar a atividade biol?gica, atrav?s da t?cnica de prote?nas precipit?veis por fen?is (PPP). As vari?veis TCE, TCPB e TCT apresentadas foram influenciadas pelas diferentes esp?cies (P?0,05). A fra??o TCFB n?o foi constatada nas leguminosas. Os pesos moleculares (Mw) foram influenciados pelas diferentes esp?cies (P?0,05), variando de 737 a 1168 Da. As caracter?sticas estruturais (PP, PD, PC e PD:PC) tiveram varia??o entre as esp?cies estudadas. Objetivou-se com o terceiro cap?tulo avaliar a metanog?nese (metano total (CH4-total), incubado (CH4 inc.) e fermentado (CH4 ferm.) e os par?metros de fermenta??o ruminal (produ??o de g?s total (PGT), pH, am?nia (N-NH3), ?cidos graxos de cadeia curta (AGCC) e digestibilidade in vitro da mat?ria org?nica (DIVMO) frente aos TC presentes nas leguminosas e feno de Urochloa brizantha cv. marandu como controle (CTL). Foi testado tamb?m o efeito do polietileno glicol (PEG) sobre a fra??o folha do sabi?, que teve conte?do de TC de 15,97%. N?o foi observado altera??o no pH (P?0,05) para os tratamentos avaliados. No entanto, foram observadas diminui??o da produ??o total de g?s e produ??o de metano para todos os tratamentos com presen?a de TC (P?0,05). Para o tratamento com PEG houve aumento de 27,01 (8% PEG) e 35,01 (16% PEG) na produ??o total de g?s e 3,59 (8% PEG) e 4,15 (16% PEG) na produ??o de metano. GUA, FLE, SABc e SABf foram capazes de modificar (P?0,05) a concentra??o de N-NH3 (mg/dL) juntamente com o CTL, que tamb?m apresentou valores inferiores comparado as leguminosas com tra?os e aus?ncia do TC (ETL, CRA e GLI). Houve diferen?a (P?0,05) para DIVMO entre as leguminosas e o controle, observou-se menor digestibilidade (P?0,05) para FLE, GUA e SABf, em rela??o ao CTL, n?o sendo digest?vel o SABc. A DIVMO foi afetada pela adi??o de PEG na dieta do SABf. No perfil dos AGCC houve diferen?a (P?0,05) para os tratamentos avaliados, com menor valor para as leguminosas com presen?a de TC. O quarto cap?tulo teve como objetivo testar o efeito da t?cnica de inibi??o da migra??o larval (IML) in vitro do TC proveniente das leguminosas em estudo (FLE, CRA, GUA, GLI, EST, SABf e SABc) sobre as larvas infectantes L3 do nemat?de o Haemonchus contortus (HC) comparando com Ivermectina e controle negativo (l?quido ruminal e tamp?o). Entre as leguminosas estudadas o SABf e GUA n?o diferiram entre si (P?0,05), com as maiores porcentagens IML (34,75% e 34,33%). As leguminosas GUA, FLE e SABc n?o diferiram entre si (P?0,05), apresentando moderados valores de IML (30,25%, 30,0% e 29,75%, respectivamente). Entre as leguminosas estudadas a menor porcentagem de IML foi para CRA (18,46%), GLI (23,75%) e controle negativo (l?quido de r?men e tamp?o) valores pr?ximos do controle positivo com Ivermectina (22,0%).

Made available in DSpace on 2014-06-11T19:23:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-06Bitstream added on 2014-06-13T20:10:51Z : No. of bitstreams: 1 campanha_rb_me_sjrp_parcial.pdf: 94727 bytes, checksum: a521baee0344f893db4ddd3e800f17bf (MD5) Bitstreams deleted on 2015-06-03T11:42:49Z: campanha_rb_me_sjrp_parcial.pdf,. Added 1 bitstream(s) on 2015-06-03T11:44:13Z : No. of bitstreams: 1 000624134_20150806.pdf: 1531119 bytes, checksum: 2dfd54b4b280060729591429aa12bdef (MD5) Bitstreams deleted on 2015-08-07T12:19:56Z: 000624134_20150806.pdf,. Added 1 bitstream(s) on 2015-08-07T12:20:58Z : No. of bitstreams: 1 000624134.pdf: 2009868 bytes, checksum: b037ab2970b2d5ab5615092c0c8d45a9 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Amido é um polímero semicristalino constituído basicamente por amilose e amilopectina. Seus grânulos são formados por regiões amorfas intercaladas com áreas mais densas compostas por lamelas alternadas de material cristalino e amorfo. O empacotamento das moléculas no grânulo é dependente da fonte botânica. Raízes e tubérculos são ricos em amido e seu plantio não requer muito investimento. Assim, o interesse industrial vem aumentando. O conhecimento da estrutura granular é fundamental para melhor entendimento das propriedades funcionais e melhor utilização do amido. A hidrólise ácida é uma técnica muito utilizada no estudo da estrutura do amido. O tratamento do amido com H2SO4 15% produz uma fração ácido-resistente, com baixa massa molar, conhecida como dextrina Naegeli (DN). O objetivo deste trabalho foi determinar a estrutura granular dos amidos de mandioca, batata, batata-doce e mandioquinha-salsa através da hidrólise ácida. Os amidos foram incubados com H2SO4 15,3% a 38ºC, por até 30 dias, e suas DN foram analisadas. A hidrólise ácida ocorreu em duas etapas: a primeira foi atribuída à rápida degradação das áreas amorfas dos grânulos, enquanto a segunda fase correspondeu à lenta hidrólise das regiões cristalinas. O amido de mandioquinha-salsa foi o mais suscetível à hidrólise, enquanto que os amidos de batata e batata-doce foram os mais resistentes. Os amidos de batata e mandioquinha-salsa apresentaram padrões cristalinos tipo B e mostraram maiores proporções de cadeias laterais longas da amilopectina (GP 37) do que os amidos de mandioca (tipo CA) e batata-doce (tipo C). Além de grande proporção de cadeias longas, o amido de mandioquinha-salsa também apresentou grande proporção de cadeias curtas (32,0%). O amido de mandioca também apresentou grande proporção de cadeias curtas (30,5%). Esses amidos mostraram um ombro em GP 17-21... / Starch is a semi-crystalline polymer composed mainly of amylose and amylopectin. The starch granules are formed by successive layers that include amorphous areas interspersed with more dense areas composed of alternated lamellae of crystalline and amorphous material. Packing of amylose and amylopectin into granules is dependent of botanical source. Tubers and roots are rich in starch and their cultivation does not require much investment. Thus, the industrial interest has increased. Knowledge of the starch structure is fundamental for better understanding the functional properties and better utilization of the starch. Acid hydrolysis is widely used to study starch structure. Treatment of starch with 15% H2SO4 solution produces an acid-resistant fraction with low molecular weight known as Naegeli dextrin (ND). Objective of this study was to determine the structural characteristics of cassava, potato, sweet potato and Peruvian carrot starches by using acid hydrolysis. The starches were submitted to 15.3% H2SO4 at 38ºC for up to 30 days and their ND were analyzed. Acid hydrolysis displayed two phases: the first one was attributed to faster degradation of amorphous areas of granules, whereas the second phase corresponded to slower hydrolysis of crystalline regions. Peruvian carrot starch was the most susceptible to hydrolysis, whereas potato and sweet potato starches were the most resistant. Potato and Peruvian carrot starches displayed B-type X-ray pattern and had larger proportions of long branch-chains of amylopectin (DP 37) than cassava (CA-type) and sweet potato (C-type) starches. Beyond the great proportion of long branch-chains, the Peruvian carrot starch also showed great proportion of short branch-chains (32.0%). Cassava starch also had great proportion of short branch-chains (30.5%). These starches displayed a shoulder at DP 17-21 on branch chain-length distribution... (Complete abstract click electronic access below)

Resumo: Avaliou-se o efeito do IAF residual sob a estrutura do pasto de capim-Tanzânia e o comportamento ingestivo de cabras Boer X Saanen sob lotação intermitente. O experimento foi conduzido no período de fevereiro/2008 a agosto/2008. A área foi subdividida em 18 piquetes de 243 m2 para o estudo de 3 tratamentos dispostos segundo um delineamento em blocos casualizados com 6 repetições para avaliações referentes à gramínea. As avaliações referentes ao comportamento ingestivo das cabras foram realizadas, na mesma área, em 12 piquetes, alocados em blocos casualizados, com 4 repetições. Os tratamentos consistiram em 3 IAF residuais (0,8 - 1,6 - 2,4). O período de descanso foi adotado segundo o critério de 95% de IL ou quando as leituras permanecerem constantes durante 3 semanas consecutivas. Antes do pastejo foi feito a medição da altura da vegetação em 20 pontos distintos e colheu-se 6 amostras ao nível do solo por piquete. Os animais pastejaram até atingir o IAF pré-determinado para o resíduo. Foi aferido o índice de área foliar (IAF) e da interceptação luminosa (IL) com o aparelho analisador de dossel (AccuPAR LP-80 da Decagon - USA). As amostras colhidas foram pesadas e, por conseguinte, retirada um alíquota de 400 g para a separação dos componentes morfológicos (folha, colmo + bainha e material morto), estes foram secados em estufa (55 ºC) por 72h e pesados, a fim de estimar as características estruturais. Avaliou-se a densidade volumétrica da forragem, com o auxílio do "ponto inclinado" e feita as análises laboratoriais a fim de estimar o que os caprinos consumiram durante o pastejo. As amostras analisadas foram colhidas pelo método do pastejo simulado. Também foram mensuradas variáveis que refletem o comportamento ingestivo em pastejo como a massa, a área, a profundidade e a taxa do bocado. No pré-pastejo, os valores de interceptação... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The effect residual LAI was evaluate under structural characteristics of tanzania grass and the ingestivo behavior by goats Saanen X Boer at rotational stocking. The experiment was conducted in the period on February/2008 to August/2008. The area was divided into 18 paddocks of 243 m2 for the study with 3 treatments arranged in a randomized blocks design with 6 replications for the grasses evaluations. The evaluations relating to the ingestive behavior of the goats were carried out, in the same area, in 12 paddocks, allocated in randomized blocks design with 4 replications. The treatments consisted in 3 levels of residual LAI (0,8 - 1,6 - 2,4). The period of rest was adopted according to the criterion of 95% of LI or when the readability remained constant during 3 consecutive weeks. Before each period of grazing have been done 20 points of height of vegetation were taken, 6 samples at the level of the soil were collected for each paddock . The animals grazed until the the remainder LAI pre-determined. Measurements were made of leaf area index (LAI) and the light interception (LI) with the equipment AccuPAR LP-80 Decagon - USA. Samples were weighed and, 400 g were kept for the separation of morphologic components (leaf, stem lap and dead). These were dried at 55° C for 72h and weighed in order to estimate the herbage mass. Density was evaluated by volume of forage with the inclined point quadrat. Laboratory analyzes were done in order to estimate the goats fed during the grazing and the samples were collected by the handing plucking method. They were measured variables which reflect the ingestive behavior in grazing as the bite mass, area, depth and the rate . Pre-grazing, the values of light interception and leaf area index were not significantly affected by treatments (P>0.05). The values of time of pre grazing of the animals... (Complete abstract click electronic access below) / Orientadora: Ana Cláudia Ruggieri / Coorientadora: Izabelle Auxiliadora Molina de Almeida Teixeira / Banca: Ricardo Andrade Reis / Banca: Carlos Augusto de Miranda Gomide / Mestre

Made available in DSpace on 2014-08-20T14:38:51Z (GMT). No. of bitstreams: 1 Tese_Vivian_Brusius_Cassal.pdf: 1112596 bytes, checksum: 03070922896986823ec3a34e6322d0b6 (MD5) Previous issue date: 2010-06-14 / There were two experiments conducted in the field, area of at the Estação Experimental Terras Baixas (ETB) - Embrapa Clima Temperado, Capão do Leão- RS, during the period at , respectively October 2007 to November 2008 and december 2008 to january 2010. The objective of first study was to evaluate the practical application of herbicide, overseeded annual ryegrass and grazing for the introduction of peanut in natural pasture. The experiments were conducted from October 2007 to November 2008, at the Estação Experimental Terras Baixas (ETB) - Embrapa Clima Temperado, Capão do Leão - RS. The treatments were arranged in a randomized block design in split plots with four replications. The plots were represented by the treatments with and without herbicide (commercial herbicide Glyphosate at a dosage of 3L ha-1). The subplots were defined by the absence of peanut, the presence of peanut, the presence of peanut overseeded with annual ryegrass. The sub sub-plots were made by with and without grazing in winter and early spring. The frequencies of species of native pasture were not influenced by grazing and overseeded ryegrass. The introduction of peanut is benefited by the herbicide. However, it is a practice that causes a significant reduction of forage species of forage interest. The overseeded of annual ryegrass as a practice in the introduction of peanuts provides a favorable environment for the difficulties of winter to the legume. The second study was objective was to evaluate the intercropping of forage peanut and Tifton 85 submitted to coutting in Autumn, through structural characteristics and dry matter yield. The experiment was conducted from December 2008 to January 2010, at the Estação Experimental Terras Baixas (ETB) - Embrapa Clima Temperado, Capão do Leão - RS.The area was fertilized with 60 kg ha-1 P2O5, 80 kg ha-1 K2O and 20 kg N ha-1 at December 15 ,2009. Treatments were arranged in randomized complete blocks in split plots with four replications. The plots of 20m2 each, consisted of three row spacings and seedlings of Tifton 85 (1m x 1m, 1m x 0.75m and 1m x 0.50m) and three spacings among of plants Tifton 85 (no forage peanuts, one line and two lines forage peanuts). April 17, 2009 these parcels were divided in half, getting cut autumnal management (with and cut) leaving a 11 residue of 5 cm of soil. From May to September, at intervals of 30 days, evaluations was made of structural characteristics of Tifton 85 and forage peanuts. After cutting autumnal in September 24, November 20,2009 and January 13, 2010 cuts were performed to evaluate the dry matter yield of Tifton 85 and peanuts. Intercropping with peanut and cutting autumnal change the structural characteristics of Tifton 85. The DM yield of Tifton 85 (spring and summer) is less cut-autumn when the temperature does not limit its growth. / Foram realizados dois experimentos em área da Embrapa Clima Temperado (ETB) no município do Capão do Leão, RS, durante os períodos de outubro de 2007 a novembro de 2008 e de dezembro de 2008 a janeiro de 2010. O objetivo do primeiro trabalho foi avaliar o efeito das práticas aplicação de herbicida, da sobressemeadura de azevém anual e do pastejo sobre a introdução de amendoim forrageiro e a dinâmica da vegetação em áreas de vegetação campestre secundária. Os tratamentos foram arranjados em um delineamento de blocos ao acaso com parcelas subsubdivididas e quatro repetições. As parcelas principais foram representadas pelos tratamentos com e sem herbicida (herbicida comercial a base de Glifosato, na dosagem de 3Lha-1). As subparcelas foram definidas pela ausência; presença de amendoim forrageiro e presença de amendoim sobressemeado com azevém anual. As subsubparcelas constituiram-se de sem e com pastejo no inverno e início da primavera. As freqüências das espécies forrageiras nativas não foram influenciadas pelo pastejo e sobressemadura de azevém. A introdução de amendoim forrageiro é beneficiada pela aplicação de herbicida. Entretanto, é uma prática que provoca redução significativa de espécies nativas de interesse forrageiro. A sobressemeadura de azevém anual como prática na introdução de amendoim proporcionando um ambiente favorável às dificuldades do inverno para a leguminosa. O segundo trabalho teve o objetivo avaliar as características estruturais e produção de matéria seca da consorciação de Tifton 85 e amendoim forrageiro submetida à corte no período outonal. A área foi adubada com 60 kg ha-1de P2O5, 80 kg ha-1 de K2O e 20 kg ha-1de N em 15/12/2008. Os tratamentos foram arranjados em delineamento de blocos completos ao acaso em parcelas divididas com quatro repetições. As parcelas de 20m2 cada, consistiram de três espaçamentos dentro das linhas de Tifton 85 (1m x 1m; 1m x 0,75m e 1m x 0,50m); e três consorciações nas entre mudas de Tifton 85 (sem amendoim, uma linha e duas linhas de amendoim). No dia 17/04/09 essas parcelas foram divididas ao meio, recebendo manejo de corte outonal (com e sem corte) deixando-se um resíduo de 5cm do solo. De maio a setembro, em intervalos de 30 dias, foram realizadas as avaliações das características estruturais do Tifton 85 e do amendoim. Após o corte outonal, em 9 24/09; 20/11/09 e 13/01/10 foram realizados cortes para avaliação da produção de matéria seca de Tifton 85 e amendoim. A consorciação com amendoim e o corte outonal modificam as características estruturais do Tifton 85. A produção de MS do Tifton 85 (primavera e verão) é menor com corte outonal quando a temperatura não limita seu crescimento.