Romualdo Shigueo Fukushima

Use of lignin extracted from different plant sources as standards in the spectrophotometric acetyl bromide lignin method

A nongravimetric acetyl bromide lignin (ABL) method was evaluated to quantify lignin concentration in a variety of plant materials. The traditional approach to lignin quantification required extraction of lignin with acidic dioxane and its isolation from each plant sample to construct a standard curve via spectrophotometric analysis. Lignin concentration was then measured in pre-extracted plant cell walls. However, this presented a methodological complexity because extraction and isolation procedures are lengthy and tedious, particularly if there are many samples involved. This work was targeted to simplify lignin quantification. Our hypothesis was that any lignin, regardless of its botanical origin, could be used to construct a standard curve for the purpose of determining lignin concentration in a variety of plants. To test our hypothesis, lignins were isolated from a range of diverse plants and, along with three commercial lignins, standard curves were built and compared among them. Slopes and intercepts derived from these standard curves were close enough to allow utilization of a mean extinction coefficient in the regression equation to estimate lignin concentration in any plant, independent of its botanical origin. Lignin quantification by use of a common regression equation obviates the steps of lignin extraction, isolation, and standard curve construction, which substantially expedites the ABL method. Acetyl bromide lignin method is a fast, convenient analytical procedure that may routinely be used to quantify lignin.

Temperatura ambiente e concentrações séricas de cortisol em suínos em crescimento-terminação

Thirty-six castrated males and females Landrace x Large-White pigs (74 to 149 days of age) were randomly allotted to two environmental conditions: high temperature in a climatic chamber (HT; 22.2 to 32.8 oC) and comfort temperature in a conventional shed (CT; 17.6 to 26.6 oC), with night-and-day variations. Blood samples were weekly collected from animals of both HT and CT conditions for determination of serum cortisol levels. Cortisol levels of both sexes were not different, and there was no interaction with environmental temperature. Pigs of HT showed significantly higher average cortisol level (P<0.01) than the CT ones (7.06 and 4.82 mg/dL, respectively). Increasing in serum cortisol was continuous and linear (P<0.05) during the experimental period, suggesting the cortisol as a possible indicator of the heat stress in growing-finishing pigs.

Use of photocatalytic reduction to hasten preparation of culture media for saccharolytic Clostridium species

Cysteine is the preferred reducing agent used in the preparation of culture media for the growth of many strictly anaerobic microorganisms; however, redox potential reduction of cysteine is very slow, making it inconvenient if the medium is needed immediately or in large quantity. The time required to reduce culture medium containing resazurin (an indicator of reducing conditions) was dramatically shortened when the medium, after being injected with the reducing agent cysteine, was irradiated with incandescent light from a halogen lamp. Light intensity had an effect upon reduction time: tubes kept in the dark took more than 12 h to achieve the desired degree of anaerobiosis (measured spectrophotometrically by the bleaching of the indicator, resazurin) while tubes subjected to ordinary laboratory illumination were reduced in about 2 h. When exposed to maximum light intensity (equivalent to a regular 100 watt bulb lamp) tubes could be made anaerobic in less than 20 min. Cysteine was essential for the bleaching of resazurin. Evidence that adequate anaerobiosis was achieved by light irradiation was provided by the fact that four Clostridium strains and one Thermoanaerobacter strain displayed similar growth (measured by lag time, growth rate, and extent of growth) in media reduced under high intensity light or under normal laboratory illumination.

Digestibilidade do bagaço de cana-de-açúcar tratado com reagentes químicos e pressão de vapor

Com o objetivo de elevar a digestibilidade do bagaco de cana-de-acucar, este residuo agro-industrial foi tratado com inumeros reagentes quimicos acompanhados ou nao de tratamento fisico. Apos ensaios preliminares, nos quais diversos agentes deslignificantes foram avaliados, dez tratamentos foram selecionados para serem melhor estudados em ensaios de digestibilidade in vitro da materia seca e da materia orgânica. Em seguida, para o ensaio de digestibilidade in vivo, foram feitas quatro dietas a base de: 1 - Bagaco auto-hidrolisado (BAH), pressao de 17 kgf/cm2 por 5 min; 2 - Bagaco tratado com 4% Na2S + 6% NaOH, pressao de 12 kgf/cm2 por 8 min; 3 - Bagaco tratado com 2% Na2S + 3% NaOH, pressao de 12 kgf/cm2 por 8 min; e 4 - Bagaco tratado com 9% H2O2 + 7% NaOH, a 70oC por 8 min. Bagaco tratado com 4% Na2S + 6% NaOH e submetido a 12 kgf/cm2 de pressao apresentou os melhores coeficientes de digestibilidade da materia seca, materia orgânica, fibra em detergente neutro e fibra em detergente acido e o maior valor de nutrientes digestiveis totais. Em seguida, o bagaco tratado com 9% H2O2 + 7% NaOH a 70oC por 8 min apresentou os melhores resultados. Piores resultados foram observados para o bagaco hidrolizado. A melhor digestibilidade de algumas das dietas, particularmente das fracoes fibrosas, sugere a exiquibilidade do emprego de menores quantidades de alimento concentrado em dietas a base de bagaco de cana tratado quimica/fisicamente.

Substitution of crude cell wall for neutral detergent fibre in the equations of the Cornell Net Carbohydrate and Protein System that predict carbohydrate fractions: application to sunflower (Helianthus annuus L.)

Prediction of carbohydrate fractions using equations from the Cornell Net Carbohydrate and Protein System (CNCPS) is a valuable tool to assess the nutritional value of forages. In this paper, these carbohydrate fractions were predicted using data from three sunflower (Helianthus annuus L.) cultivars, fresh or as silage. The CNCPS equations for fractions B2 and C include measurement of ash and protein-free neutral detergent fibre (NDF) as one of their components. However, NDF lacks pectin and other non-starch polysaccharides that are found in the cell wall (CW) matrix, so this work compared the use of a crude CW preparation instead of NDF in the CNCPS equations. There were no differences in the estimates of fractions B1 and C when CW replaced NDF; however, there were differences in fractions A and B2. Some of the CNCPS equations could be simplified when using CW instead of NDF. Notably, lignin could be expressed as a proportion of DM, rather than on the basis of ash and protein-free NDF, when predicting CNCPS fraction C. The CNCPS fraction B1 (starch + pectin) values were lower than pectin determined through wet chemistry. This finding, along with the results obtained by the substitution of CW for NDF in the CNCPS equations, suggests that pectin was not part of fraction B1 but present in fraction A. We suggest that pectin and other non-starch polysaccharides that are dissolved by the neutral detergent solution be allocated to a specific fraction (B2) and that another fraction (B3) be adopted for the digestible cell wall carbohydrates.

Rendimento e comportamento espectrofotométrico da lignina extraída de preparações de parede celular, fibra em detergente neutro ou fibra em detergente ácido

The lignin extracted from the forages by the acetyl bromide reagent (acetyl bromide lignin - AcBrL) to be used as a reference standard for the quantitative spectrophotometric determination of lignin could not originate from intact plant because of interference of other substances, which absorb ultraviolet light at the same wavelength of lignin. It is then recommended that lignin extraction be performed in one of the following materials: cell wall itself (CW), neutral detergent fiber (NDF), or acid detergent fiber (ADF). The lignin extraction yields as well as the spectrographic pattern of those were evaluated in these three compounds that came from diverse forage plants. On the average, extraction yields of AcBrL were fairly uniform among them; however as the concentration of ADF was the lowest among all preparations (mainly due to hemicellulose solubilization) and as far this preparation did not exhibit higher lignin extraction capacity, the AcBrL concentration from ADF on a whole plant basis was the lowest observed. The ultraviolet light absorption from the diverse lignin was unequal, as revealed by the graphic spectrograms, which would suggest that the cell wall preparation used for lignin isolation must be the same for the final determination of lignin concentration.

Influence of environmental temperature, dietary energy level and sex on performance and carcass characteristics of pigs.

Suinos sao sensiveis a altas temperaturas e os mecanismos de termorregulacao representam custos energeticos direcionados a perda de calor corporal, reduzindo o bem-estar e o desempenho produtivo, e alterando a qualidade de carcaca. O objetivo deste estudo foi avaliar os efeitos do sexo e do nivel energetico da dieta em suinos em crescimento-terminacao submetidos as variacoes sazonais de temperatura caracteristicas de clima subtropical umido e propor um modelo matematico que prediga o desempenho dos animais e caracteristicas de carcaca. Vinte e oito leitoes mesticos foram distribuidos aleatoriamente a 12 tratamentos em arranjo fatorial 2x2x3 (2 sexos, 2 condicoes ambientais e 3 niveis de energia na dieta). A condicao de estresse calorico (câmara climatica) apresentou temperaturas de 31 oC as 7:00 e 22 oC as 17:00 (com maxima de 33 oC) e a condicao de conforto termico (galpao) apresentou temperaturas de 18 oC as 7:00 e 24 oC as 17:00 (com maxima de 27 oC). Os animais foram alimentados ad libitum com dietas contendo 12,2 (baixo), 13,6 (medio) e 15,0 (alto) MJ EM/kg MS. O consumo voluntario de racao, ganho de peso diario e peso corporal final foram maiores (P<0,01) na condicao de conforto termico e sofreram influencias do sexo (P<0,01) para os suinos em crescimento. A conversao alimentar decresceu conforme aumentou a energia da dieta (P<0,01), com valores de 2,67, 2,59 e 2,32 (para 12,2, 13,6 e 15,0 MJ EM / kg MS, respectivamente). Houve interacao entre nivel dietetico de energia e sexo somente para ganho diario de peso. Para os suinos em terminacao, tambem se observou efeito da condicao ambiental (P<0,01) sobre o consumo voluntario de racao, ganho diario de peso e peso corporal final, com o desempenho dos animais sendo melhor na condicao de conforto termico. Os valores de conversao alimentar foram 3,55:1, 3,42:1 e 2,95:1 para niveis de energia baixo, medio e alto, respectivamente. Foram observadas interacoes entre nivel de energia e sexo para as variaveis consumo de racao, ganho diario de peso e peso final (P<0,05). O rendimento e qualidade de carcaca foram afetados pelas condicoes ambientais e nivel dietetico de energia. Tanto o peso da carcaca quente, como da carcaca resfriada aumentaram com o aumento da energia na dieta. Apos o resfriamento, o peso da carcaca aumentou em 1,142 kg/MJ EM, enquanto a espessura de toucinho esteve acima de 252 mm/MJ EM. A espessura do musculo longissimus thoracis foi 16 mm menor nos animais em estresse calorico, mas o conteudo de carne magra foi 2,68% maior nestes animais. Equacoes de regressao para predicao de valores de desempenho nas diversas situacoes estudadas foram propostas.

Comparação entre dois métodos analíticos para determinação da lignina de algumas gramíneas forrageiras

RESUMO - Foram comparados dois mOtodos analiticos para a determinacao da lignina (lignina emdetergente AEcido - LDA e lignina permanganato de potAEssio - LPer) bem como para averiguar a possi-vel relacao dos teores desse componente com a digestibilidade da fibra dos seguintes fenos: andropogon(Andropogon gayanus ); aveia ( Avena sativa ); e dois tipos de coast-cross ( Cynodon dactylon ), um bemfenado e outro de baixa qualidade. Os valores de LDA e LPer foram diferentes (p ≤ 0,05) entre asgramineas estudadas, com as concentracies de LPer consistentemente mais baixas do que as de LDA.Foram detectadas diferencas (p ≤ 0,05) nos valores de digestibilidade da fibra em detergente neutro(FDN) e da fibra em detergente AEcido (FDA), porOm, nao foi detectada clara relacao desses valorescom teores de lignina. Os dados sugerem que a concentracao de lignina nao O o principal fator aexplicar um dado valor de digestibilidade.Termos para indexacao: digestibilidade, feno, fibra em detergente AEcido, fibra em detergente neutro.COMPARISON BETWEEN TWO ANALYTICAL METHODS FOR DETERMININGLIGNIN CONCENTRATION OF SOME GRASS FORAGESABSTRACT - This work was carried out aiming to compare lignin concentration of some grass for-ages through two analytical methods (acid detergent lignin - ADL and permanganate lignin - PerL) aswell to verify a possible relationship of lignin concentration with fiber digestion of the following grasshays: andropogon (Andropogon gayanus); oats (Avena sativa); a good quality and another of poorquality coast-cross ( Cynodon dactylon ). Acid detergent and permanganate lignin values were different(p ≤ 0.05) among the hays, however PerL concentrations were consistently lower than ADL values.There were differences (p ≤ 0.05) among the digestibility of neutral and acid detergent fiber fractions,however a clear relationship between these values with lignin concentration could not be assessed.The data suggested that lignin concentration, taken individually, is not the only factor to explain agiven value of digestibility.Index terms: digestibility, hay, neutral detergent fiber, acid detergent fiber.

Composição fenólica de ligninas dioxano determinadas pela reação oxidativa com o nitrobenzeno

The correct quantification of lignin concentration in forages through the spectrophotometric method presumes the existence of a reference standard. This standard must have a phenolic composition similar to the cell wall lignin. The objective of this work was to verify if the lignins extracted with acidic dioxane solution to be used as reference standard would present the same variation in the phenolic composition as it occurs in the cell wall lignin. Bromegrass, corn and red clover cell wall samples were submitted to the method for extraction of lignins with an acidic dioxane solution. The phenolic composition of the extracted lignins was analyzed by alkaline nitrobenzene oxidation followed by HPLC separation. Extracted lignins confirmed that they have phenolic composition variation the same way as do intact lignins present in the cell wall and that grass lignins showed substantial presence of cinnamic acids. Concerning to phenolic composition lignins extracted by acidic dioxane may potentially be used as reference standards in the spectrophotometric analysis.

Evaluating internal and external markers versus fecal sampling procedure interactions when estimating intake in dairy cows consuming a corn silage-based diet

Feed intake assessment is a valuable tool for herd management decisions. The use of markers, either internal or external, is currently the most used technique for estimating feed intake in production animals. The experiment used 10 multiparous Holstein cows fed a corn silage-based diet, with 55:45 forage-to-concentrate ratio, the average fecal recovery (FR) of TiO2 was higher than FR of Cr2O3, and both FR were more than unity. With internal markers, acetyl bromide lignin and cutin FR were lower than unity, and average FR for indigestible neutral detergent fiber (iNDF) and indigestible acid detergent fiber (iADF) was 1.5. The FR was unaffected by the fecal sampling procedure and appears to be an intrinsic property of each molecule and how it interacts with digesta. Of the 2 external markers, only Cr2O3 produced accurate fecal output (FO) estimates and the same happened to dry matter digestibility (DMD) when iNDF and iADF were used. Estimates for DMD and FO were affected by sampling procedure; 72-h bulk [sub-sample from total feces collection (TFC)] sampling consistently produced accurate results. The grab (sub-samples taken at specific times during the day) sampling procedures were accurate when using either of the indigestible fibers (iNDF or iADF) to estimate DMD. However, grab sampling procedures can only be recommended when concomitant TFC is performed on at least one animal per treatment to determine FR. Under these conditions, Cr2O3 is a suitable marker for estimating FO, and iNDF and iADF are adequate for estimating DMD. Moreover, the Cr2O3+iADF marker pair produces accurate dry matter intake estimates and deserves further attention in ruminant nutrition studies. The method of dosing the external markers is extremely important and greatly affects and determines results. Whichever the method, it must allow the animals to display normal feeding behavior and not affect performance. The grab sampling procedures can replace TFC (once FR is established), which may open new possibilities for pasture-based or collectively housed animals.