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Copyright of Montes is the property of Colegio y Asociación de Ingenieros de Montes and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Lignocellulosic biomass has a tremendous potential for obtaining value-added products useful in applications in medicine, food and feed, textile, biofuels, carbon fibres etc. Amongst the three main components, lignin is the most abundant natural aromatic polymer that is the least valorised. The main enzymes involved in lignin degradation are mainly oxidases (laccases and peroxidases), but several esterases (hydroxycinnamic acid esterases) are also important for their activity on releasing lignin from hemicellulose and cellulose. This study is focused on describing the most used compounds that can mimic the structure of lignin components and presents the available methods used for identifying microorganisms capable of degrading lignin. Also, it provides an array of industrial applications for depolymerised lignin. [ABSTRACT FROM AUTHOR]

The main purpose of this research study is to examine the chemical composition of Samanea saman (Rain tree) wood, oil, and seed meal through chemical analyses to explore potential applications. The study area is a 300ha extension with S. saman trees that are used for shading mainly. Wood and seeds are collected, dried, and crushed. Wood analyses characterize its humidity, extractives, ashes, lignin, cellulose, and holocellulose. Oil is extracted from seeds to assess its physicochemical properties and fatty acid profile. Seed meal is examined by conducting a proximal analysis. The results reveal that S. saman wood is rich in cellulose (45.3%) and holocellulose (63.6%). S. saman oil contains a high proportion (81.77%) of unsaturated fats and its seed meal has high protein and carbohydrate content. In conclusion, the chemical compositions of S. saman wood, oil, and seed meal have adequate characteristics to make paper, medicines, and food, among other derivatives. [ABSTRACT FROM AUTHOR]

Objectives. Test the effect of wet extrusion and the application of two alkaline compounds on the in vitro digestibility of dry matter (IVDDM) and neutral detergent fiber (IVDNDF) of maralfalfa grass. Materials and methods. 48 samples of 51 days of regrowth were chopped and assigned to eight treatments: raw, chopped, and dehydrated grass (CTRL); raw, chopped, and extruded grass (EXTR); EXTR treated with 0.45, 0.90, and 1.35% of lime (Ca(OH)2) or urea for 21 days in micro-silos under aerobic conditions (EXTR0.45Ca, EXTR0.90Ca, EXTR1.35Ca, EXTR0.45U, EXTR0.90U, and EXTR1.35U, respectively). The content of dry matter (DM), nitrogen (N), calcium (Ca), neutral detergent fiber (NDF), acid detergent lignin (ADL) and the in vitro digestibility of dry matter (IVDDM) and NDF (IVDNDF) were determined for each sample. Results. The EXTR presented lower N content, higher NDF content, and higher IVDNDF than the CTRL. On the other hand, the EXTR1.35Ca treatment showed the highest Ca concentration and the highest IVDDM and IVDNDF, while the EXTR0.90U treatment presented the highest N concentration and an IVDNDF statistically similar to that of the EXTR1.35Ca. Conclusions. The wet extrusion of maralfalfa grass alone increases IVDNDF; however, IVDDM and IVDNDF are maximized when treated with 1.35% of Ca(OH)2. [ABSTRACT FROM AUTHOR]

Identifying the type and best lignocellulosic biomass pretreatment conditions for bioconversion processes requires structural and compositional changes evaluating after its application. This paper presents a review of the main methods used for pretreatments evaluation in lignocellulosic biomass, with emphasis in those used to improve biogas production. It is concluded that modern procedures that use techniques such as chromatography for quantification are more accurate, but very expensive and laborious, which is why classical methods, such as Weender and Van Soest for the analysis of structural carbohydrates and lignin, continue to be used, and potentiometry and colorimetry results attractive alternatives in other determinations. The qualitative changes of its components, such as relocation and the way in which they interact, is another important aspect when interpreting results obtained by applying pretreatments. [ABSTRACT FROM AUTHOR]

This research was based in the study of the physi-cochemical properties of the cocoa shell, variety CCN 51. In this sense, tests were carried out on the residues to determine the lignocellulose components, together with thermo-gravimetric tests and scanning electron microscopy. The results of the chemical composition showed values in a higher proportion of lignin, followed by cellulose and hemicellulose. In the thermal analysis, an initial peak associated with evaporated moisture was presented, in addition to fourfragmentation stages, which correspond to the primary components of the residue. In the microstructure, a porous surface was observed, with the presence of micro pores and cell walls. In general, it can be concluded that the analyzed cocoa shell residues are a viable alternative of raw material from renewable sources in the agricultural sectorforthe manufacture of agglomerated boards with industrial applications. [ABSTRACT FROM AUTHOR]

Introduction: The growth of global energy demand results in numerous environmental challenges and an energy deficit. In this context the biomass use ois a promising way to produce sustainable energy through anaerobic digestion with pretreatment stage included. Objective: To present a summary of the main pretreatment methods reported to improve biogas production from lignocellulosic materials, as well as an approach on clean solvent-based methods. Materials and Methods: The main used sources were doctoral thesis and research articles where pre-treatment techniques were used, as well as published previously reviews about this topic. Results and Discussion: The results reported by different authors in the use of pre-treatments are described, considering as fundamental aspects the variation in the structure and methane yield, which can be different between dissimilar biomass using similar conditions. The formation of inhibitory compounds is more likely when steam explosion and acid pretreatments are used, or when it is working under severe temperature and time conditions. Clean solvent-based methods increase lignin removal and are therefore promising for biogas production. Conclusions: The inclusion of a pre-treatment stage prior to anaerobic digestion process allows to obtain better methane yields, if a good process selection parameters is made. [ABSTRACT FROM AUTHOR]

The present study evaluates the effect of a laccase from Aspergillus sp. to expose cellulose contained in both sugarcane (Saccharum officinarum, BCA) and Opuntia-ficus cactus (BOF) bagasse. The kinetic parameters of the enzymatic activity were calculated for each of the materials, using the initial rates method at various bagasse:solution ratios (10 g:L to 50 g:L) and a total reaction time of 1 h. The assays presented a non-enzymatic removal of extractables by the buffer effect, under the evaluated reaction conditions. On the other hand, there was no cellulose or hemicellulose dissolution but there was lignin. Therefore, the results were analyzed, considering the Michaelis-Menten equation and using the disappearance rate of the glignin:L ratio as a basis. Through a Lineweaver-Burk linearization, the best fit of the values was obtained, where Vmax = 14.9566 glignin:L/h and km = 40.2011 glignin:L for BCA assays (R = 0.9933) and Vmax = 26.8300 glignin:L/h and km = 43.5575 glignin:L for BOF assays (R = 0.9972). Based on the above, although laccase presented a similar enzymatic affinity for both bagasse, a better catalytic efficiency is predicted towards lignin removal from BOF (0.6160). [ABSTRACT FROM AUTHOR]

Introduction: There are several types of lignin and, among them, which derives from processes that use organic solvents in the presence of catalyst, acid or basic has less environmental impact with respect to conventional ones since organic solvents are easily recovered by distillation, also this type of lignins, has specific uses because its structure. Hydrolysis of sugarcane bagasse produces lignin-rich currents that can be integrated into the biorefinery concept. Objective: Demonstrate the economic feasibility of integrating the lignin production process into the biorefinery concept based on its characteristics and the knowledge of its producers at the international level. Materials and methods: A search (briefing) that provides useful data for the development of the lignin obtaining process is carried out, based on this process is integrated into the concept of biorefinery and its economic indicators are determined. Results and Discussion: The applications of lignin as a result of bagasse hydrolysis can be: the elaboration of carbon fibers, vanillin, and in the production of phenol derivatives. By assessing the feasibility of investment in the biorefinery scheme with the integration of lignin, dynamic profitability indicators are obtained that demonstrate the feasibility of the proposal, maintaining the recovery of investment in 5.2 years as de Armas, (2019). Conclusions: The proposed process is justified with the applications of lignin and can be integrated into the biorefinery while maintaining its profitability. [ABSTRACT FROM AUTHOR]

Copyright of Revista de la Sociedad Química del Perú is the property of Sociedad Quimica del Peru and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In a randomized block design with a 2 x 2 factorial arrangement, the quality, development and biomass accumulation of Cenchrus purpureus vc. CT-115 was studied. The treatments consisted of application of irrigation, or not, during the dry period, with a cut at 56 and 98 days. The length of the stem (cm), leaf length (cm), length and thickness of the second internode (cm) and the total yields, and leaves and stems (tMSha-1), as well as the percentages of CP, ADF, NDF and lignin in leaf were measured. No interactions between age and irrigation were found for any of the variables. The yield of leaves, stems and total were higher (P = 0.0001) when irrigation was applied and cut at 98 days. The long stem and leaf indicators, stem thickness and internode length were better when irrigation was applied. The leaf CP was higher (P = 0.0007) at 56 days with 11.45% and 8.30% at 98 days. The CP was higher (P = 0.0064) at 11.05% with irrigation and 8.70 % without irrigation. It is concluded that the increases in total DM production (tMSha-1) and the quality of the biomass indicate the possibility of shortening the resting times and increase the productive capacity of systems with biomass banks of Cuba CT-115 when irrigation is applied. [ABSTRACT FROM AUTHOR]

In this study, the main wood chemical composition of Ceiba pentandra, Hevea brasiliensis and Ochroma pyramidale was determined with the aim of providing knowledge on wood chemistry of tropical species and information to explore possible chemical applications. For this, the contents of ash, ethanol-benzene extracts, ethanol extracts, lignin, holocellulose, cellulose and hemicelluloses were quantified in the stem at three height levels (bottom, middle, and top). Results of the chemical analysis showed that concentrations of the determined constituents varied within the stem of the individual wood species and also among species. The average amount of chemical compounds among the species was 0,44% - 1,64% for ash; 1,42% - 3,42% for ethanol-benzene extracts; 1,88% - 5,07% for ethanol extracts; 3,83% - 8,46% for total extracts; 19,71% - 26,83% for lignin, 77,73% - 83,52% for holocellulose; 39,67% - 47,63% for a-cellulose and 33,79% - 42,85% for hemicelluloses. According to the obtained contents of lignin, a-cellulose and hemicelluloses, the wood of these species could be used in pulping and bioconversion processes. [ABSTRACT FROM AUTHOR]

In recent years, interest has won biocontrol Mycosphaerella fijiensis with the use of microorganisms or their products. Nevertheless, the knowledge of the biochemical events involved in Musa-M. fijiensis-microorganism interaction, is still limited. The objective was to determine the histochemical response of 'Grande naine' (Musa AAA) plants inoculated or not with the pathogen in the presence of culture filtrate of Bacillus pumilus CCIBP-C5. For this, techniques that allow visualization of callose, superoxide anion, lignin and phenolic compounds in the early days post inoculation (dpi) were used. As a result, at 6 dpi callose deposition were observed within the stomata in plants where the culture filtrate was applied regardless of the presence or absence of the pathogen. Furthermore, a blue halo was observed around stomas, indicative of the presence of superoxide anion. It was not possible to detect accumulation of lignin or phenolic compounds with the technique used. It was demonstrated the accumulation of biochemical compounds related to defense response of 'Grande naine' plants to pathogen infection. Furthermore, it was shown that the plant responds in early infection with the use of bacterial culture filtrates. These results demonstrate the possible mechanism of induction of defense response in plants of Musa sp. in the presence of bacterial culture filtrate. [ABSTRACT FROM AUTHOR]

The decrease of the fossil fuels stocks and environment deterioration have required the searching of renewable sources, among them, the lignocellulose biomass (LCB) constitutes a safe and inexhaustible alternative as the base for the future industry according to the modern concept of biorefinery. The LCB has a very complex structure where their components are strongly bonded, that is why their separation requires several stages of the consumption of chemical and energy. The microwave is one of the new technologies used for the conversion of the LCB into products of high added value. The objective of this paper has been to explore the influence of the treatment with microwaves on the hydrolyzed bagasse in order to get cellulose pulp. This material is treated with different concentrations of sodium hydroxide (14, 17 and 20 %) and microwaves exposure times (15, 30 and 45 minutes). The temperature (88 °C), the particle size, the solid to liquid ratio and the microwaves power are kept constants. The solid phase is characterized by means of its chemical composition, while the liquid phase is characterized by means of the contents of total sugars. The higher value of cellulose content (83.2 %) is obtained with 20 % of sodium hydroxide at 30 minutes of microwave exposition and 88 °C, which is comparable with the results obtained by the traditional pulping method at 160 °C. [ABSTRACT FROM AUTHOR]

The present study shows the results of obtaining fermentable sugars using elephant grass (Pennisetum purpureum) feedstock. The concentration effect of acetic acid (CH3COOH) and sodium chlorite (NaClO2) was assessed on the removal of lignin hemicellulose complex. A comparison was made about method, using basic pretreatment with sodium hydroxide (NaOH) and hydrogen peroxide (H2O2). The Saccharification step is carried out by enzymatic hydrolysis method that is performed using cellulase and β-glucosidase. The results show in the case of pretreatment with NaClO2 and CH3COOH a percentage of saccharification of 80.87% compared to NaOH pretreatment with a percentage 56.82% and hydrogen peroxide with a percentage of 44.75%. [ABSTRACT FROM AUTHOR]

A residue, called lignin, is generated in the chemical treatment of lignocellulosic materials in order to obtain cellulose. Lignin has become an attractive product because it constitutes a potential source of precursors of high added value, from its depolymerization, by obtaining aromatic compounds of low molecular weight. In this work, is realized the alkaline hydrolysis of bagasse lignin by using a sodium hydroxide load of 7 %, a solid to liquid ratio of 1:10, temperatures at 100 and 180 °C respectively, for 6 h, in such a way that occurs the rupture of C-C and C-O bonds. Subsequently extraction in toluene was realized and the organic phase was characterized by gas chromatography coupled to mass spectrometry (GC-MS). [ABSTRACT FROM AUTHOR]

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The effect of different alkaline pretreatment conditions with sodium hydroxide (NaOH) on the recuperation of cellulosic fraction, lignin removal and ethanol production was evaluated through simultaneous saccharification and fermentation of elephant grass and king grass ((Pennisetum purpureum and Pennisetum hybridum). These types of grass are potential raw materials for bioethanol production from cellulosic fraction. Results obtained in ethanol production show that under pretreatment conditions of 120°C, 60 minutes, 2%(w/w) of NaOH and a liquid to solid ratio of 20 (w/w), the highest ethanol concentrations are obtained: 27.7 g/L and 26.1 g/L for king grass and elephant grass respectively, in 24 hours of fermentation. Furthermore, under the evaluated conditions it was observed that lignin removal was 88.4% for elephant grass and 94.0% for king grass. The detoxification stage eliminates inhibitors formed during pretreatment, which affects the hydrolysis and fermentation. [ABSTRACT FROM AUTHOR]

A chemical analysis was performed to determine the major chemical components of five pine species in the municipality of Morelia, Michoacán. The pine species studied were: Pinus leiophylla, P. michoacana var. cornuta, P. montezumae, P. oocarpa and P. teocote. The pH value, ash, ash analysis, extractives, holocellulose, lignin and tannins content was determined for each pine species. The results were in the range of 4,0 to 4,4 for pH, 0,3% ash in all species (calcium and potassium in higher concentration), 17,9% to 25,4% for soda solubility, 7,6% to 8,2% total extractives, 68,1% to 74,7% for holocellulose, 24% to 28,5% for lignin and 0,07% to 0,12% for tannins. Through the applied extraction the wood solubility followed the sequence: water > ciclohexan > aceton > methanol. Analysis of variance of the data showed that pH, soda solubility, holocellulose, lignin and tannins did vary among pine species (P < 0,05). [ABSTRACT FROM AUTHOR]

El objetivo fue determinar los cambios en rendimiento de materia seca (RMS) y calidad del forraje de sorgo sembrado en surcos distanciados a 75 y 20 cm, y en densidades de 33 y 65 semillas m², cuando la planta tiene una concentración de materia seca de 300 g kg-1. No hubo interacción año x distancia entre surcos en los caracteres, excepto en altura de planta. Efecto de año existió, excepto en concentración de materia seca de la planta (322 g kg-1) y en proteína (97.6 g kg-1). El RMS por año varió de 10 t (2007) a 17 t ha-1 (2009), y de 10 a 16.6 t ha-1 en distancias de 75 y 20 cm, respectivamente. El peso seco de panículas fue 109.4 g y 158.1 g kg-1 mayor en 2007 que en 2008 y 2009, respectivamente, y el peso de mil granos fue 13.66 g kg-1 mayor en 2007 que al promedio de los dos años restantes. La digestibilidad fue 89.5 y 39.9 g kg-1 menor en 2007 y 2008, respectivamente, que en 2009. Hubo correlación entre digestibilidad y cenizas (-0.94**), fibra detergente ácido (-0.93**) y lignina detergente ácido (-0.85*). La proteína fue 15.2 g kg-1 mayor en surcos a 25 cm que a 75 cm. No hubo interacción año x densidad de siembra, ni la densidad afectó el RMS ni la calidad del forraje. El RMS y la calidad del forraje de sorgo fueron mejorados al combinar densidad de siembra de 33 semillas m2 con distancia de 20 cm entre surcos. Sorghum dry matter yield (DMY) and forage quality were evaluated at two row spacings (75 and 20 cm) and two sowing densities (33 and 65 seeds m-2), with harvest at a 300 g kg-1 whole plant dry matter concentration. Trials covered three consecutive growing seasons (2007, 2008 and 2009) with progressively lower annual rainfall. The year x row spacing interaction had no effect on traits, except for plant height. Year did affect the traits, except for whole plant dry matter concentration (322 g kg-1) and protein content (97.6 g kg-1). Annual DMY ranged from 10 t (2007) to 17 t ha-1 (2009), and 10 t (75 cm row spacing) to 16.6 t ha-1 (20 cm). In 2007, panicle dry weight was 109.4 g kg-1 higher than in 2008 and 158.1 g kg-1 higher compared to 2009. Thousand-grain weight was 13.66 g kg-1 higher in 2007 than the average of the two following years. Compared to 2009, digestibility was 89.5 g kg-1 lower in 2007 and 39.9 g kg-1 lower in 2008. There was correlation between digestibility and ash content (-0.94**), acid detergent fiber (-0.93**) and acid detergent lignin (-0.85*). Protein concentration was 15.2 g kg-1 higher at the 20 cm spacing than at the 75 cm. No year x sowing density interaction was present, and sowing density did not affect DMY or forage quality. Sorghum DMY and forage quality were improved using a 33 seeds m2 sowing density and 20 cm row spacing. [ABSTRACT FROM AUTHOR]

Copyright of Innotec is the property of Laboratorio Tecnologico del Uruguay and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Innotec is the property of Laboratorio Tecnologico del Uruguay and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective. Macroscopically and diffractografically evaluate bone response to hydroxyapatite - lignin compound implanted in rabbit tibial medullary canal. Materials and methods. 20 New Zealand rabbits were used. Each of their left tibias was treated with the compound; the right tibias were not treated, serving as control. Bone fracture of approximately 4 mm in diameter in the lateral proximal tibia was performed, reaching the medullary canal. From the compound, 1000 mg were dissolved in 10 drops of saline solution using part of the mass to cover the twisted end of the intra-medullary pin, (Schanz steel F 138, size 2.5 mm for cortical bone) and the rest was introduced in the medullary canal of the group treated with the help of a catheter size 16 and disposable syringe. After introduction of 7 cm in length of the pin in the medullary canal, the anatomical blueprint was closed. The same was done in the control tibias, without use of the compound. Macroscopic and difractographic evauation of the medullary content which grew at the base of the pins was assessed at eight, 30, 60, 90 and 120 days post-surgery. Results. Each macroscopic evaluation date showed that the tendency of bone marrow in the treated rabbits was to regenerate and lose compound visibility, which was shown through X-ray diffraction, where crystalline tissue was found to be compatible with the mineral component of the bone. Conclusion. The compound can lead bone formation of intra-medullary nail without affecting the regeneration of bone marrow. [ABSTRACT FROM AUTHOR]

Copyright of Avances en Ciencias e Ingeniería is the property of Avances en Ciencias e Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Avances en Ciencias e Ingeniería is the property of Avances en Ciencias e Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to assess the use as growing substrate for the fungus Pleurotus ostreatus, falling of the oak dead leaves in a forest relict in La Capilla rural area, Cajibio (Cauca) was evaluated during 6 months, choosing mature trees with a chest height diameter (DAP) between 35 and 37 cm were chosen, getting an average of 7,41 kg of dead leaves per tree. Fungus growing in oak dead leaves mixed with sugar cane bagasse and 5 substrates: T1: bagasse 100%, T2: oak 100%, T3: oak 75% and bagasse 25%, T4: oak 50% and bagasse 50% and T5: oak 25% and bagasse 75% reaching biological efficiencies of 221,1%, 44,35%, 52,78%, 90,30% and 109,12% respectively. Was an inverse association between the content of oak leaf and efficiencies due to the nature leathery and waxy leaf. Most of the carpophores showed 5 and 12 cm and contamination caused by competing fungi of the Trichoderma sp. genus. Changes were detected in the depleted substrate composition, mainly minerals and protein increase and decrease of fiber in the bagasse and oak litter, being suitable for animal feed polygastric for mycelial protein content, presence of cellulose and lower lignin content. [ABSTRACT FROM AUTHOR]

Copyright of Innotec is the property of Laboratorio Tecnologico del Uruguay and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Lignocellulose constitutes a raw material with considerable potential for the production of fermentable sugars and the generation of biofuels. In nature, lignocellulosic waste from forestry, agriculture and gardening acts as the preferred carbon source of a number of bacteria and fungi endowed with the required ligninolytic machinery. These hydrolytic activities could potentially be complemented with those from other proteins that remodel the structure of cell walls, such as expansins, a group of proteins originally identified in plants that have the capacity of relaxing cell wall tension to allow cell growth. Expansins participate in processes where remodeling of the plant cell wall is required: organogenesis, fruit ripening, and growth of the pollen tube, among others. Expansins and expansin-like proteins have been proposed to act by disrupting the hydrogen bonds binding together cellulose fibrils and cellulose and other polysaccharides through a non-enzymatic process, enhancing subsequent degradation. In this manuscript, a review on plant cell wall compo-sition and ligninolytic enzymes from cell wall-degrading bacteria and fungi is presented. Proteins with expansin-like activity, their properties and their potential application to enhance sugar release from lignocellulosic material are also reviewed. [ABSTRACT FROM AUTHOR]

In the present study an analysis of the adsorption of Ni and V on lignin from national black liquor was carried out using thermodynamic principles. A comparison was established between both the precipitated lignins and one commercial analytical grade lignin. The adsorptive capacity of both materials was evaluated through the construction of isotherms whose data was fitted to the following models: Freundlich, Langmuir and Redlich - Peterson. For all these models, the best fit for the obtained data was the one of Langmuir's. For the adsorption process, the thermodynamic parameters ΔG°, ΔH° y ΔS°, were also calculated. The adsorption enthalpy yielded values of less than 40 KJ / mol, which can not clarify what type of adsorption (physical or chemical) is ocurring, since both types of adsorption may be present. With respect to the Gibbs free energy, negative values were obtained for the adsorption of Ni, suggesting a spontaneous process, while for V values were positive, suggesting a not spontaneous process. In the case of the calculated entropy, a negative value was obtained for the adsorption of nickel, which is indicative of the adsorption process. On the other hand, for V this value was small and positive, which combined with the low adsorption obtained, does not permit to accurately interpret the results. [ABSTRACT FROM AUTHOR]

Copyright of Tecnura is the property of Tecnura and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Chapingo Serie Ciencias Forestales is the property of Universidad Autonoma Chapingo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Oak chips from six lots barrels of different origin were Summit to a hidroalcoholysis by reflux with a rum distillate. With gravimetric analysis and IR spectroscopy the lignin extracted was quantified and identified, and by means of HPLC the aromatic aldehydes and acids were analyzed. Significant differences for all compounds were found; the lignin IR spectra matched with the reported one and, concentrations in a decrease order was: syringaldehyde, vanillin, coniferaldehyde and sinapaldehyde form aromatic aldehydes and, for acids: protocatechuic, siringic, vanillic, ferulic and coumaric. There is not a good correlation between the lignin content and aromatic aldehydes and acids concentrations and the results shown that the structural compositions of lignin in defferent oak Woods are variable in monomeric units. According to the results, the composition of rums aged in these oak wood will be different in term of aldehyhes an acids from lignin degradation. [ABSTRACT FROM AUTHOR]

Copyright of Revista Chapingo Serie Ciencias Forestales is the property of Universidad Autonoma Chapingo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Knowledge about biochemical events involved in both compatible and incompatible interaction in Musa-M. fijiensis pathosystem is still very limited. So, the use of tools to study fast and simply plant defence mechanisms against the pathogen is very necessary. The aim of this study was to detect defence-related compounds in leaves of Musa sp. plants inoculated with M. fijiensis, using histochemical techniques. Histochemical techniques were used to visualize lignin, hydrogen peroxide and phenolic compounds in different states of symptoms in Musa acuminata genotypes: 'Grande naine' (susceptible) and 'Calcutta 4' (resistant). It was observed the presence of lignin deposition and accumulation of hydrogen peroxide and phenolics in plant tissue in all the disease symptoms either in susceptible or resistant genotypes. The presence of these compounds increased with the development of symptoms. The accumulation of hydrogen peroxide was greater in 'Calcutta 4' plants compared to 'Grande naine'. Results showed that using histochemical techniques, the accumulation of some biochemical compounds related to plant defence response against pathogen infection could be observed. These results provide further evidences of the mechanisms of plant defence in Musa-M. fijiensis interaction. [ABSTRACT FROM AUTHOR]

Copyright of Innotec is the property of Laboratorio Tecnologico del Uruguay and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Among soil microorganisms, Actinomycetes play an important role in the sustainability of natural and agricultural systems: decomposition of organic matter; degradation of recalcitrant compounds like lignin; nitrogen fixation; degradation of agricultural chemicals and biological control in plants and animals. We evaluated their diversity in soils under three different vegetation covers (pasture, tropical primary forest and stubble) at two depths in the Southern Colombian Amazon border. We collected five replicates per vegetation type (in each, three samples at 0-20cm and three at 20-30cm; for a total of 30 samples). Abundance and phenotypic diversity were determined by plate counting. Genomic DNA was extracted from the isolates: the 16s rDNA gene was amplified with specific primers, and its genetic diversity was estimated by means of an amplified restriction analysis (ARDRA). Actynomicetes abundance varied with vegetation and depth, possibly reflecting presence of earthworms, macro-fauna and physico-chemical characteristics associated to fertility, as well as organic matter, total bases, and optimal capacity to cationic interchange. Primary forests had the highest diversity. Sixteen morpho-types (six genera) were identified; Streptomyces was the most abundant everywhere. The heterogeneity of ARDRA patterns prevented species identification because of the intra-species variability in sequences of 16s rDNA operons. This community is a biological indicator of landscape alteration and could include new bio-active compounds of pharmaceutical interest. Rev. Biol. Trop. 57 (4): 1119-1139. Epub 2009 December 01. [ABSTRACT FROM AUTHOR]

In this work was made a comparative technical-economic analysis of the possibilities of ethanol production from xilose and glucose or ethanol production from glucose and furfural from xilose. It was consider a second stage of Organosolv pretreatment by the higher quality lignin separation and the Presac system for glucose fermentation with S. cereviceae yeast. In the study are analyzed both alternatives including moreover, the lignin supply for raw material from other productions. The cost of ethanol liter, the cost of production and PRD were considerer economic indicators. The results show that the alternative considering the ethanol productions from xilosa present lower cost by ethanol liter and PRD upper to 6.5 years, but higher values of the cost of production with relation the alternative that considering the furfural from xilosa. [ABSTRACT FROM AUTHOR]

This work presents an alternative of industrial use of the banana rachis (the woody center of the cluster of bananas), as source of fibers for the structure of paper. Banana rachis is considered to be an agroindustrial residue in producing countries of banana it represents 2.8 % of the cluster of Muse balbisiana and 4.4 % of the cluster of Muse acuminata. The physical and chemical structure of the rachis is almost simliar to that of the sugar cane so a chemical process similar to that employed to obtain fibers from the sugar bagasse cane was used. An experimental factorial design that allows the correlation of independent variables (cooking time, reagent concentration) in four levels with response parameters (yield, reagents consumption, rejects and residual lignin) was adopted. The rachis of Muse acuminata needs lower temperature and less reagent consumption to liberate fibers in comparison with the rachis of Muse balbisiana. Therefore yield of the fibbers from Musa acuminata is major than that of the fibbers from Musa balbisiana. [ABSTRACT FROM AUTHOR]

Copyright of Revista Chapingo Serie Ciencias Forestales is the property of Universidad Autonoma Chapingo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective. To evaluate the bio-compatibility and bone-conductivity properties of a hydroxyapatite-lignin compound Implanted in rabbit's shinbone. Material and methods. 20 rabbits (New Zealand race) were used for the experiments. In each animal, the left tibia was treated experimentally whereas the right tibia was used as experimental control. Using a manual drill, we bore a hole approximately 4mm diameter that reached the medullar canal. Each of these was subsequently treated with two tablets of the hydroxyapatite-lignln compound equivalent to 400 mg which were used to fill up the bone damage. The same surgical procedure was performed in the group of control, without using the compound. The histological evaluations were conducted at 8, 30, 60, 90 and 120 days post surgery based on four animals each time. Results. Comparison between experimental and control groups evidenced that at 30, 60, 90 and 120 days post-surgery there was an accelerated bone formation and extensive bone healing In the treated group. Conclusions. The hydroxyapatite- lignin compound allowed the growth of bone tissue from the edges to the center of the bone damage at a higher and more organized rate than in the control group. We also found the hydroxyapatite-lignin compound integrate well Into the bone tissue, which -in addition to the observations presented above - allowed us to recommend it as a biocompatible and oseoconductor substitute in the case of bone damage. [ABSTRACT FROM AUTHOR]

The vegetable lignocellulosic residues of the Universidad Industrial de Santander campus were physical, chemistry and microbiological characterized and biodegraded for wormcompost production. They were studied the effect of some variables such us air circulation and microorganism addition. These microorganisms were native acceleration products. The lignin and humins reduction presented significant differences. The biodegradation process generates more humic and fulvic acids when the vegetable residues were treated with air (overturning) and with microorganisms addition. Additionally, it was observed strong pathogenic microorganisms reduction, with pH increase, improvement of the plasticity and a regulating effect of the nutrients in the soil. In taking account the results from pilot plant, we had building a compost plant with 51 m³ of capacity. [ABSTRACT FROM AUTHOR]

In the mountain range of Álvarez, San Luis Potosi eighteen oak species have been identified; two of them (Quercus sebifera and Q. tinkhami) included into the Quercus section or white oaks are shrubs. Currently, studies are not known on the wood characteristics of these species, which are only used locally in a reduced and rudimentary way. Their chemical composition is presented here. Essays to estimate relative content (%) of lignin, extracts and ashes were carried out; specific gravity was also calculated along with volume of cellulose. Basic statistics were estimated for each parameter obtained. Variance analyses were applied between the essays sets of cellulose, lignin, ash, and extracts. Not significant differences (p> 95%) were found between species for cellulose and lignin. These results were similar to those presented by other authors for Mexican oaks. Ash volume resulted to be greater; it may be due to their particular climate and soil type, mainly. The extracts of Q. sebifera obtained by the ethanol-benzene mixture and by hot water were greater than those published for white oaks. These species were different (p > 95%) for extract content. Ash and extracts richness of these species seems to be related to their aridity adaptations. Relative basic density values for Q. sebifera were medium and high for Q. tinkhami. [ABSTRACT FROM AUTHOR]

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Plant polyphenol, including vanillin, is often used as the intermediate materials of the medicines and vanilla flavoring. In agriculture generally vanillin is produced from vanilla plant and in industry from lignin of disposed wood pulp. We have recently developed a method for the production of plant polyphenol with the excrement as a natural resource of lignin, of the herbivorous animals, by using the subcritical water. The method for using the subcritical water is superior to that of the supercritical water because in the latter complete decomposition occurs. We have successfully produced the vanillin, protocatechuic acid, vanillic acid, and syringic acid in products. Our method is simpler and more efficient not only because it requires the shorter treatment time but also because it releases less amount of carbon dioxide into the atmosphere. [ABSTRACT FROM AUTHOR]

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 Río 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 introduction of parameters like the chemical composition of wood, induce to the development of expedite methods of characterization, reproducible and low cost, once the traditional methods are slow, require a lot of manpower and have a high cost. [ABSTRACT FROM AUTHOR]

In the paper are exposed the possibilities of achieving a clean technology of production of corrugated paper from the employment of the pounding of the trash of sugar cane with ethanol. Were established the possibilities of achieving, by means of an analysis, processes of material and energy integration of the manufacture of sugar and installations of production of by-products. These processes are technologically and energetically sustainable, environmentally compatible, and economically competitive based in the benefits that can be achieved through the material and energy integration of the sugar cane by-products and the possibility of producing celluloid pulps with ethanol for corrugated cardboard, and by-products from the lignin obtained in the process. [ABSTRACT FROM AUTHOR]