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Olof Theander - One of the best experts on this subject based on the ideXlab platform.
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Chemical composition of some forages and various residues from feeding value determinations
Journal of the Science of Food and Agriculture, 2006Co-Authors: Olof Theander, Per AmanAbstract:NDF, ADF, ‘cellulose’ and IVOMD residues, from feeding value determinations, were prepared from some forages, including straw, alkali-treated straw, grass and lucerne samples. The crude protein, cellulose, hemicellulose, uronic acid, Klason Lignin, Lignin and ash contents of these residues and the corresponding original forage samples were determined together with the relative composition of the neutral sugar constituents after acid hydrolysis. Cellulose, hemicellulose and Klason Lignin were the main components in the NDF fractions but substantial amounts of crude protein (1–6%) also remained. Cellulose and Klason Lignin were the main components in the ADF fractions, but 7–14% of the fractions was hemicellulose and 1–4% crude protein. Cellulose was the main component in the ‘cellulose’ fractions, but they also contained 8–13% hemicellulose, 2–7% Klason Lignin and 2–11% ash. The composition of the IVOMD residues showed that cellulose and hemicellulose had been dissolved to about the same amounts (70–80%) and that most of the Klason Lignin remained.
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total dietary fiber determined as neutral sugar residues uronic acid residues and Klason Lignin the uppsala method collaborative study
Journal of AOAC International, 1995Co-Authors: Olof Theander, Per Aman, Eric Westerlund, Roger Andersson, D PetterssonAbstract:A joint AOAC/American Association of Cereal Chemists (AACC) collaborative study was conducted to determine by the Uppsala method the dietary fiber content and its composition in various foods. The method includes preparation of a residue by treatment with thermostable α-amylase and amyloglucosidase and then ethanol precipitation of solubilized dietary fiber components while leaving low-molecular weight carbohydrates in solution. After acid hydrolysis of residue, neutral polysaccharide residues are determined as alditol acetates by gas-liquid chromatography, uronic acid residues are determined by colorimetry, and ash-free acid-insoluble residue (Klason Lignin) is determined gravimetrically. Total dietary fiber, including enzyme-resistant starch, is calculated as the sum of nonstarch polysaccharide residues and Klason Lignin. Nine laboratories completed the study, analyzing in duplicate 8 unknown dried products that included 4 cereal products, green peas, potato fiber, carrots, and apples. Total dietary fiber contents of products tested ranged from 4.6 to 84.3%, with an average RSD R value of 8.4% (range, 4.8-11.1%). Total neutral polysaccharide residues ranged from 3.8 to 64.1%, with an average RSD R value of 7.5% (range, 5.4-10.5%). Individual neutral sugars (rhamnose, arabinose, xylose, mannose, galactose, and glucose) and uronic acid residues present at more than 1% generally had good RSD R values (3.3-22.8%), whereas, as expected for Klason Lignin, only the wheat bran sample with a high content (16%) had an excellent RSD R value (5.0%). The gas chromatographic-colorimetric-gravimetric method (Uppsala method) for determination of total dietary fiber (as neutral sugar residues, uronic acid residues, and Klason Lignin) has been adopted first action by AOAC INTERNATIONAL.
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Enzymatic/chemical analysis of dietary fiber.
Journal of AOAC International, 1994Co-Authors: Olof Theander, Per Aman, Eric Westerlund, Hadden GrahamAbstract:: The Uppsala methodology for rapid analysis and characterization of total dietary fiber, defined as the sum of dietary fiber polysaccharides (DFP) and Klason Lignin, was studied. A sugar- and starch-free residue was prepared by treatment with a thermostable amylase and amyloglucosidase. Neutral DFP residues were quantified by gas chromatography as alditol acetates after acid hydrolysis of this residue, and the acid-insoluble fraction, Klason Lignin, was determined gravimetrically. Uronic acid residues were quantified by decarboxylation of the original sample. The efficacy of the Uppsala methodology was tested with foods varying in fiber content and composition, including heat-treated samples. The present method allowed the analysis of up to 40 samples per week. It had good repeatability and coefficients of variation of 3-5% for the main fiber components. Fiber contents determined with the method were higher than those determined with a similar method that excludes Klason Lignin and starch resistant to amylases but soluble in dimethyl sulfoxide and lower than those determined with an enzymatic/gravimetric method. Important aspects of fiber analysis, like enzyme purity and the recovery of soluble fiber on ethanol precipitation, also were investigated.
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The Uppsala Method for Rapid Analysis of Total Dietary Fiber
Advances in Experimental Medicine and Biology, 1990Co-Authors: Olof Theander, Per Aman, Eric Westerlund, Hadden GrahamAbstract:An understanding of the nutritional effects of dietary fiber has been considerably hampered by the lack of an appropriate definition, and consequently of adequate analysis methods, for this component. Based on physiological criteria, Trowell (1972) defined dietary fiber as “the remnants of the plant cell-wall that are not hydrolysed by the alimentary enzymes of man”, and this was later simplified and expanded to include “the plant polysaccharides and Lignin which are resistant to hydrolysis by the enzymes of man” (Trowell et al., 1976). In 1979 we proposed that dietary fiber could be defined as the sum of non-starchy polysaccharides and Klason Lignin, and, in conjunction with this chemical definition, published the first method (the Uppsala method) for the analysis and characterization of fibers (Theander and Aman, 1979). As this analytical procedure includes ‘starch’ resistant to α-amylases and, as part of the Klason Lignin complex, other indigestible components such as tannins, cutins and Maillard products, this definition conforms well with the original definitions of Trowell and co-workers.
Jose Carlos Rodrigues - One of the best experts on this subject based on the ideXlab platform.
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ESTUDIO DEL CONTENIDO Y LA CALIDAD DE LA LigninA MEDIANTE PIRÓLISIS ANALÍTICA EN MADERA DE PINUS CARIBAEA. CONTENT AND QUALITY STUDY OF THE Lignin BY ANALYTICAL PYROLYSIS IN PINUS CARIBAEA
2020Co-Authors: Esther Álvarez Godoy, Ana Alves, Jose Carlos Rodrigues, Daniel Álvarez LazoAbstract:This work shows the Lignin content determined as well as its quality (H/G ratio) in wood samples of Pinus caribaea var caribaea from three sites at Pinar del Rio Province, Cuba. The study was carried out at the Tropical Scientific Investigation Institute, Lisbon, Portugal (Project GEMA). The Analytical pyrolysis was used as analytical method. The results represent the average of three repetitions and was obtained similar values to Klason method used as reference. An acceptable correlation was obtained between the Py-Lignin contents and Klason Lignin for this species. This may be possible to calculate the Klason Lignin through the content Py-Lignin content. The Analytic pyrolysis is of great utility in the programs of genetic improvement, in which it is necessary the analysis of many samples, since the
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Analytical pyrolysis as a direct method to determine the Lignin content in wood: Part 2: Evaluation of the common model and the influence of compression wood
Journal of Analytical and Applied Pyrolysis, 2008Co-Authors: Ana Alves, Jose Carlos Rodrigues, Rupert Wimmer, Manfred SchwanningerAbstract:Abstract In Part 1, a method for the quantification of the Lignin content (Py-Lignin) of Maritime pine and spruce wood samples directly from the pyrograms was presented (A. Alves, M. Schwanninger, H. Pereira, J. Rodrigues, J. Anal. Appl. Pyrol. 76 (2006a) 209). The good correlation found between the Py-Lignin and Klason Lignin content gave a common model to both species. In this work different larch species (Larix sp.) as well as varieties of European larch were used to evaluate this common model, revealing only small differences between the measured and the predicted Klason Lignin contents. Compression wood was included due to the difference in Lignin composition and content compared to normal wood. As the influence of compression wood was small a so-called “softwood model” including all samples was calculated (Py-Lignin = 0.7325 × Klason Lignin + 3.9195, R2 = 0.94). This can be used for pine, larch, and spruce wood with the limitation of the highest and lowest values where the species-specific models lead to better results, although more than 95% of the differences between the species-specific models and the “softwood model” lie within ±0.3%. It is expected that this model can predict the Klason Lignin content of other softwoods.
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analytical pyrolysis as a direct method to determine the Lignin content in wood part 1 comparison of pyrolysis Lignin with Klason Lignin
Journal of Analytical and Applied Pyrolysis, 2006Co-Authors: Ana Alves, Manfred Schwanninger, Helena Pereira, Jose Carlos RodriguesAbstract:Abstract In this work a method for the quantification of the Lignin content (Py-Lignin) of Maritime pine and spruce wood samples directly from the pyrograms is presented. The precision of the Py-Lignin method was 0.41% for Maritime pine (Pinus pinaster Aiton) and 0.34% for spruce (Picea abies (L.) Karst), close to the stated repeatability of the reference Klason method (0.34%). Besides apparent species-specific deviations, an average difference of 3.9 ± 0.72% compared to the Klason Lignin content was observed. Py-Lignin retains between 70 (Maritime pine) and 89% (spruce) of the variation in the Lignin amount found for the same samples by the Klason Lignin method. Good correlation was found between the Py-Lignin and Klason Lignin content, for both species but a good common model to both species was also found, which allows to calculate the Klason Lignin content from Py-Lignin content for both species using only one model.
Per Aman - One of the best experts on this subject based on the ideXlab platform.
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Chemical composition of some forages and various residues from feeding value determinations
Journal of the Science of Food and Agriculture, 2006Co-Authors: Olof Theander, Per AmanAbstract:NDF, ADF, ‘cellulose’ and IVOMD residues, from feeding value determinations, were prepared from some forages, including straw, alkali-treated straw, grass and lucerne samples. The crude protein, cellulose, hemicellulose, uronic acid, Klason Lignin, Lignin and ash contents of these residues and the corresponding original forage samples were determined together with the relative composition of the neutral sugar constituents after acid hydrolysis. Cellulose, hemicellulose and Klason Lignin were the main components in the NDF fractions but substantial amounts of crude protein (1–6%) also remained. Cellulose and Klason Lignin were the main components in the ADF fractions, but 7–14% of the fractions was hemicellulose and 1–4% crude protein. Cellulose was the main component in the ‘cellulose’ fractions, but they also contained 8–13% hemicellulose, 2–7% Klason Lignin and 2–11% ash. The composition of the IVOMD residues showed that cellulose and hemicellulose had been dissolved to about the same amounts (70–80%) and that most of the Klason Lignin remained.
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total dietary fiber determined as neutral sugar residues uronic acid residues and Klason Lignin the uppsala method collaborative study
Journal of AOAC International, 1995Co-Authors: Olof Theander, Per Aman, Eric Westerlund, Roger Andersson, D PetterssonAbstract:A joint AOAC/American Association of Cereal Chemists (AACC) collaborative study was conducted to determine by the Uppsala method the dietary fiber content and its composition in various foods. The method includes preparation of a residue by treatment with thermostable α-amylase and amyloglucosidase and then ethanol precipitation of solubilized dietary fiber components while leaving low-molecular weight carbohydrates in solution. After acid hydrolysis of residue, neutral polysaccharide residues are determined as alditol acetates by gas-liquid chromatography, uronic acid residues are determined by colorimetry, and ash-free acid-insoluble residue (Klason Lignin) is determined gravimetrically. Total dietary fiber, including enzyme-resistant starch, is calculated as the sum of nonstarch polysaccharide residues and Klason Lignin. Nine laboratories completed the study, analyzing in duplicate 8 unknown dried products that included 4 cereal products, green peas, potato fiber, carrots, and apples. Total dietary fiber contents of products tested ranged from 4.6 to 84.3%, with an average RSD R value of 8.4% (range, 4.8-11.1%). Total neutral polysaccharide residues ranged from 3.8 to 64.1%, with an average RSD R value of 7.5% (range, 5.4-10.5%). Individual neutral sugars (rhamnose, arabinose, xylose, mannose, galactose, and glucose) and uronic acid residues present at more than 1% generally had good RSD R values (3.3-22.8%), whereas, as expected for Klason Lignin, only the wheat bran sample with a high content (16%) had an excellent RSD R value (5.0%). The gas chromatographic-colorimetric-gravimetric method (Uppsala method) for determination of total dietary fiber (as neutral sugar residues, uronic acid residues, and Klason Lignin) has been adopted first action by AOAC INTERNATIONAL.
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Enzymatic/chemical analysis of dietary fiber.
Journal of AOAC International, 1994Co-Authors: Olof Theander, Per Aman, Eric Westerlund, Hadden GrahamAbstract:: The Uppsala methodology for rapid analysis and characterization of total dietary fiber, defined as the sum of dietary fiber polysaccharides (DFP) and Klason Lignin, was studied. A sugar- and starch-free residue was prepared by treatment with a thermostable amylase and amyloglucosidase. Neutral DFP residues were quantified by gas chromatography as alditol acetates after acid hydrolysis of this residue, and the acid-insoluble fraction, Klason Lignin, was determined gravimetrically. Uronic acid residues were quantified by decarboxylation of the original sample. The efficacy of the Uppsala methodology was tested with foods varying in fiber content and composition, including heat-treated samples. The present method allowed the analysis of up to 40 samples per week. It had good repeatability and coefficients of variation of 3-5% for the main fiber components. Fiber contents determined with the method were higher than those determined with a similar method that excludes Klason Lignin and starch resistant to amylases but soluble in dimethyl sulfoxide and lower than those determined with an enzymatic/gravimetric method. Important aspects of fiber analysis, like enzyme purity and the recovery of soluble fiber on ethanol precipitation, also were investigated.
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Ileal and faecal digestibility of light- or dark- coloured peas (Pisum sativum) in growing pigs
Animal Feed Science and Technology, 1993Co-Authors: Maria Abrahamsson, Hadden Graham, Y. Dandanell Daveby, Per AmanAbstract:Abstract Apparent ileal and faecal digestibilities of dietary nutrients were determined in pigs fed diets based on barley and soya-bean meal or this diet substituted by 33% light- or dark-coloured peas. The two pea types had similar gross chemical composition and amino acid profile, although the dark-coloured peas had significantly higher contents of condensed tannins and Klason Lignin, attributed mainly to polyphenols in the seed hulls. Apparent ileal digestibilities of nutrients in the pea diets varied from below 0% for Klason Lignin to more than 90% for starch. However, no significant differences were obtained between the two pea diets, indicating that polyphenols in the seed hulls of dark-coloured peas did not interfere with ileal digestion of major nutrients or amino acids when fed to growing pigs. However, the faecal apparent digestibilities of fibre components were generally lower in the dark-coloured pea diet than in either the control or light-coloured pea diets.
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The Uppsala Method for Rapid Analysis of Total Dietary Fiber
Advances in Experimental Medicine and Biology, 1990Co-Authors: Olof Theander, Per Aman, Eric Westerlund, Hadden GrahamAbstract:An understanding of the nutritional effects of dietary fiber has been considerably hampered by the lack of an appropriate definition, and consequently of adequate analysis methods, for this component. Based on physiological criteria, Trowell (1972) defined dietary fiber as “the remnants of the plant cell-wall that are not hydrolysed by the alimentary enzymes of man”, and this was later simplified and expanded to include “the plant polysaccharides and Lignin which are resistant to hydrolysis by the enzymes of man” (Trowell et al., 1976). In 1979 we proposed that dietary fiber could be defined as the sum of non-starchy polysaccharides and Klason Lignin, and, in conjunction with this chemical definition, published the first method (the Uppsala method) for the analysis and characterization of fibers (Theander and Aman, 1979). As this analytical procedure includes ‘starch’ resistant to α-amylases and, as part of the Klason Lignin complex, other indigestible components such as tannins, cutins and Maillard products, this definition conforms well with the original definitions of Trowell and co-workers.
Manfred Schwanninger - One of the best experts on this subject based on the ideXlab platform.
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Analytical pyrolysis as a direct method to determine the Lignin content in wood: Part 2: Evaluation of the common model and the influence of compression wood
Journal of Analytical and Applied Pyrolysis, 2008Co-Authors: Ana Alves, Jose Carlos Rodrigues, Rupert Wimmer, Manfred SchwanningerAbstract:Abstract In Part 1, a method for the quantification of the Lignin content (Py-Lignin) of Maritime pine and spruce wood samples directly from the pyrograms was presented (A. Alves, M. Schwanninger, H. Pereira, J. Rodrigues, J. Anal. Appl. Pyrol. 76 (2006a) 209). The good correlation found between the Py-Lignin and Klason Lignin content gave a common model to both species. In this work different larch species (Larix sp.) as well as varieties of European larch were used to evaluate this common model, revealing only small differences between the measured and the predicted Klason Lignin contents. Compression wood was included due to the difference in Lignin composition and content compared to normal wood. As the influence of compression wood was small a so-called “softwood model” including all samples was calculated (Py-Lignin = 0.7325 × Klason Lignin + 3.9195, R2 = 0.94). This can be used for pine, larch, and spruce wood with the limitation of the highest and lowest values where the species-specific models lead to better results, although more than 95% of the differences between the species-specific models and the “softwood model” lie within ±0.3%. It is expected that this model can predict the Klason Lignin content of other softwoods.
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analytical pyrolysis as a direct method to determine the Lignin content in wood part 1 comparison of pyrolysis Lignin with Klason Lignin
Journal of Analytical and Applied Pyrolysis, 2006Co-Authors: Ana Alves, Manfred Schwanninger, Helena Pereira, Jose Carlos RodriguesAbstract:Abstract In this work a method for the quantification of the Lignin content (Py-Lignin) of Maritime pine and spruce wood samples directly from the pyrograms is presented. The precision of the Py-Lignin method was 0.41% for Maritime pine (Pinus pinaster Aiton) and 0.34% for spruce (Picea abies (L.) Karst), close to the stated repeatability of the reference Klason method (0.34%). Besides apparent species-specific deviations, an average difference of 3.9 ± 0.72% compared to the Klason Lignin content was observed. Py-Lignin retains between 70 (Maritime pine) and 89% (spruce) of the variation in the Lignin amount found for the same samples by the Klason Lignin method. Good correlation was found between the Py-Lignin and Klason Lignin content, for both species but a good common model to both species was also found, which allows to calculate the Klason Lignin content from Py-Lignin content for both species using only one model.
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Klason Lignin modifications to improve the precision of the standardized determination
Holzforschung, 2002Co-Authors: Manfred Schwanninger, Barbara HinterstoisserAbstract:The Lignin content in wood is generally determined with a standardized method. It is shown that with minor modifications, e. g., particle size, temperature and adherence to handling times, the standard deviation could be decreased substantially. Pooled standard deviations of 0.045 %, based on 30 determinations in immediate succession, and 0.11 %, based on 400 determinations in randomized order, were obtained, which are well qualified for the calibration of secondary analytical methods such as NIR or Raman spectrometry. As a consequence of finer grinding, an identical sample can be used for Lignin determination and for investigations in the mid infrared region without regrinding or fractionating.
Maria Dicola - One of the best experts on this subject based on the ideXlab platform.
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Chemical Composition of Second Rotation Populus Hybrid NE-388
Wood and Fiber Science, 2007Co-Authors: Paul R. Blankenhorn, Todd W. Bowersox, Charles H. Strauss, Lee R. Stover, Kevin R. Kessler, Maria DicolaAbstract:The influence of management strategy and rotation on specific gravity and chemical content (extractive, holocellulose, alpha-cellulose, and Klason Lignin) values for second rotation 4-year-old Populus Hybrid NE-388 wood and bark specimens were investigated. Specific gravity values for wood were lowest for fertilization and fertilization/irrigation strategies and for bark were highest for fertilization and fertilization/irrigation strategies compared to control and irrigation strategies. Management strategies had little effect on the holocellulose and alpha-cellulose values for the second rotation. Management strategy and rotation had significant effects on extractive and Klason Lignin contents for bark and the extractive content for wood. Second rotation average specific gravity values for wood were similar to or higher than first rotation values and average Klason Lignin content values for bark were higher than first rotation values.
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Effects of Management Strategy and Site On Selected Properties of First Rotation Populus Hybrid NE-388
Wood and Fiber Science, 2007Co-Authors: Paul R. Blankenhorn, Todd W. Bowersox, Charles H. Strauss, Gwen L. Stimely, Lee R. Stover, Maria DicolaAbstract:The influence of management strategy and site on specific gravity and chemical content (extractive, holocellulose, alpha-cellulose, and Klason Lignin) values for 1- to 4-year-old first rotation Populus Hybrid NE-388 wood and bark specimens was investigated. Specific gravity, extractive content, and Klason Lignin values decreased with increasing age for wood, while extractive content and Klason Lignin values decreased with increasing age for bark. All other determinations generally increased with age for wood and bark. Statistical comparisons were made between sites and among management strategies. Management strategies and sites influenced the specific gravity and chemical content properties, with management strategies influencing the specific gravity and chemical content values of wood more than site.