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From Endoplasmic Reticulum （ER） to Nucleus： EIN2 Bridges the Gap in Ethylene Signaling

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Molecular Plant 2013年第1期6卷 11-14页

作者： Yusi Ji Hongwei Guo State Key Laboratory of Protein and Plant Gene Research College of Life Sciences Peking University Beijing 100871 China Peking-Tsinghua Center for Life Sciences Beijing 100871China

The phytohormone ethylene plays essential roles in regu- lating plant growth and development. Understanding the mechanism of ethylene biosynthesis, signal transduction, and downstream responses is of great importance to frame the entire processes of plant growth. Genetic and biochemical approaches were applied in recent years to help establish an approximately linear ethylene signaling pathway.

关键词： Plant cell walls Energy production Biofuels Design hemicellulose Carbohydrates Alternative fuel The global scope

Fibrous Fractionation of Cocoa Pod Husks Alkali Extraction

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Fibrous Fractionation of Cocoa Pod Husks Alkali Extraction

Overview of biomass pretreatment for cellulosic ethanol production

中国营养学会第十五届全国营养科学大会

作者： Jia Wang Aerospace Center Hospital Aerospace Center Hospital (ASCH)

Cellulose, hemicellulose and lignin from cocoa pod husks were fractionated by alkali solution by using 0.5 mol/L 1.0 mol/L 1.5 mol/L concentration of NaOH for 3 hours in total. The raw materials were pretreated by 1-Cycle and 2-Cycle to obtain cellulose hemicellulose and lignin. The effects of three different concentration extraction solutions and two extraction methods on cellulose yield were compared and chemical and physical properties including water retention capacity, oil retention capacity were analyzed. In this paper, the high yield(52.8%-90.5%) of the total dietary fiber was extracted by alkali extraction. The relatively high total dietary fiber(> 50%) content of cacao pod husks indicates good dietary fiber potential. The hemicellulose(7%-15.8%) extracted in 2-Cycles was less than the hemicellulose extracted in 1-Cycle(7.6%-13.7%). The chemical and physical properties including water retention capacity and oil retention capacity were also characterized. Describe the monosaccharides composition of hemicellulose extracted by 1-Cycles. Results showed that the WRC(4.37 g-6.80 g/g) of hemicellulose increased as the concentration of the alkaline solution increased during the extraction process. Conversely, as the concentration of the alkaline solution increased, the ORC decreased(from 6.30 g to 3.76 g). hemicellulose extracted by 1.5 mol/L NaOH showed shear thinning property, while hemicellulose extracted by 0.5 M NaOH observed more Newtonian fluid property. Methods Alkali extraction previously is shown as a promising method for the separation. 5 g of the dry mill sample was and mixed with 200 mls of three different concentrations of alkali solutions(0.5 mol/L NaOH, 1.0 mol/L NaOH and 1.5 mol/L NaOH) and stirred at 200 rpm, 50 °C. The project designed two extraction methods. 1-Cycle: extraction once. 200 ml NaOH was added in one portion, and extracted at 50 °C, 200 rpm for 3 hours, and then the next step centrifugation was carried out. 2-Cycle: extracted twice. F

关键词： cocoa pod husks dietary fiber hemicellulose chemical composition alkali extraction rheological properties

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International Journal of Agricultural and Biological Engineering 2009年第3期2卷 51-68页

作者： Yi Zheng Zhongli Pan Ruihong Zhang Biological and Agricultural Engineering Department University of CaliforniaOne Shields AvenueDavisCA 95616USA Processed Foods Research Unit USDA-ARS-WRRC800 Buchanan St.AlbanyCA 94710USA

Bioconversion of lignocellulosic biomass to ethanol is significantly hindered by the structural and chemical complexity of biomass,which makes these materials a challenge to be used as feedstocks for cellulosic ethanol *** and hemicellulose,when hydrolyzed into their component sugars,can be converted into ethanol through well established fermentation ***,sugars necessary for fermentation are trapped inside the crosslinking structure of the ***,pretreatment of biomass is always necessary to remove and/or modify the surrounding matrix of lignin and hemicellulose prior to the enzymatic hydrolysis of the polysaccharides(cellulose and hemicellulose)in the *** refers to a process that converts lignocellulosic biomass from its native form,in which it is recalcitrant to cellulase enzyme systems,into a form for which cellulose hydrolysis is much more *** general,pretreatment methods can be classified into three categories,including physical,chemical,and biological *** subject of this paper emphasizes the biomass pretreatment in preparation for enzymatic hydrolysis and microbial fermentation for cellulosic ethanol *** primarily covers the impact of biomass structural and compositional features on the pretreatment,the characteristics of different pretreatment methods,the pretreatment study status,challenges,and future research targets.

关键词： lignocellulosic biomass pretreatment cellulosic ethanol enzymatic hydrolysis fermentation cellulose hemicellulose lignin

Upgrading Paper-grade Softwood Kraft Pulp to Dissolving Pulp by Cold Caustic Extraction

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Paper And Biomaterials 2016年第1期1卷 31-37页

作者： Chao Tian QingXian Miao LinQiang Zheng YongHao Ni China National Pulp and Paper Research Institute Beijing 100102 China Limerick Pulp and Paper Centre Department of Chemical Engineering University of New Brunswick Fredericton NB E3B 5A3 Canada Tianjin Key Laboratory of Pulp and Paper Tianjin University of Science and Technology Tianjin 300457 China College of Material Engineering Fujian Agriculture and Forestry University Fuzhou Fujian Province 350002 China

Cold caustic extraction has potential applications in the production of dissolving-grade pulps due to its ability to selectively remove hemicellulose from lignocellulosic materials. In this study,we demonstrate the conversion of paper-grade kraft pulp into dissolving pulp by a single-stage cold caustic extraction. Under the extraction conditions of 12 wt% NaOH lye,11% pulp consistency,a temperature of 35℃,and 2 h,a paper-grade softwood kraft pulp was purified to high-grade dissolving pulp with 97. 1% α-cellulose content,1. 2% pentosane content,and narrowed molecular weight distribution. The resulting extraction filtrate was concentrated by nano-filtration to obtain the hemicellulose content of 59. 0 g / L,while the permeate was a clear Na OH solution with 10. 9 wt% concentration. A process configuration was also proposed,integrating this cold caustic extraction process with existing pulp and paper production and multi-purpose utilization of the extraction filtrate.

关键词： cold caustic extraction dissolving pulp α-cellulose membrane filtration hemicellulose

Modelling the Suitability of Pine Sawdust for Energy Production via Biomass Steam Explosion

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Smart Grid and Renewable Energy 2014年第1期5卷 1-7页

作者： Zephania Chaula Mahir Said Geoffrey John Samwel Manyele Cuthbert Mhilu Department of Chemical and Mining Engineering University of Dar es Salam Dar es Salam Tanzania Department of Mechanical and Industrial Engineering and Technology University of Dar es Salam Dar es Salaam Tanzania Department of Sustainable Energy Science and Engineering The Nelson Mandela African Institute of Science and Technology Arusha Tanzania

Biomass material as a source of fuel is difficult to handle, transport, store, and utilize in its original form. To overcome these challenges and make it suitable for energy prodution, the material must be pre-treated. Biomass steam explosion is one of the promising pretreatment methods where moisture and hemicellulose are removed in order to improve biomass storage and fuel properties. This paper is aimed to model the suitability of pine saw dust for energy production through steam explosion process. The peak property method was used to determine the kinetic parameters. The model has shown that suitable operating conditions for steam explosion process to remove moisture and hemicellulose from pine sawdust. The temperature and pressure ranges attained in the current study are 260 -317 ℃ (533 -590 K), 4.7 -10.8 MPa, respectively.

关键词： Biomass Pretreatment hemicellulose Kinetics Pine Sawdust Steam Explosion

Biomass-derived Porous Carbon Materials for Supercapacitor Electrodes:A Review

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Paper And Biomaterials 2020年第2期5卷 60-75页

作者： Huimei Wang Zhong Liu Lanfeng Hui Lan Ma Tianjin Key Laboratory of Pulp and Paper Tianjin University of Science and TechnologyTianjin300457China

The development of renewable,cost-efficient,and environmentally friendly electrode materials with excellent performance is urgently needed for improving supercapacitors(SCs).Recently,biomass-derived porous carbons(BPCs)have received increasing attention due to their excellent physical and chemical properties,widespread availability,and low production *** this review,the progress in preparing BPCs and the properties of prepared BPCs are presented and *** addition,the applications of BPCs as electrode materials for supercapacitors are also *** importantly,the pore structure and surface properties of BPCs are all determining factors to improve electrochemical ***,a high energy density and power density can be pursued by using composites based on BPCs as electrode materials,of which combining transition metallic oxide with BPCs is one of the most attractive ***,rational design of BPCs with respect to the supercapacitor's performance should be conducted in the future.

关键词： biomass-derived porous carbon supercapacitor cellulose hemicellulose lignin activation

Observations of Wood Cell Walls with a Scanning Probe Microscope

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Materials Sciences and Applications 2016年第10期7卷 644-653页

作者： Manami Yamashita Masato Yoshida Miyuki Matsuo Saori Sato Hiroyuki Yamamoto Graduate School of Bio-agricultural Science Nagoya University Nagoya Japan

Scanning Probe Microscopes (SPMs) observe specimen surfaces with probes by detecting the physical amount of a material between the cantilever and the surface. SPMs have a high resolution and can measure mechanical characteristics such as stiffness, adsorptive properties, and viscoelasticity. These features make it easy to identify the surface structure of complex materials;therefore, the use of SPMs has increased in recent years. Wood cell walls are primarily composed of cellulose, hemicellulose, and lignin. It is believed that hemicellulose and lignin surround the cellulose framework;however, their detailed formation remains unknown. Therefore, we observed wood cell walls via scanning probe microscopy to try to reveal the formation of the cellulose framework. We determined that the size of the cellulose microfibril bundle and hemicellulose lignin module composite was 18.48 nm based on topography and that the size of the cellulose microfibril bundle was 15.33 nm based on phase images. In the viscoelasticity image, we found that the viscoelasticities of each cell wall of the same cell were not the same. This is because the cellulose microfibrils in each cell wall lean in different directions. The angle between the leaning of the cellulose microfibril and the cantilever affects the viscoelasticity measurement.

关键词： Scanning Probe Microscope Wood Cell Wall Cellulose Microfibril hemicellulose Lignin

Effects of Lignocellulosic in Wood Used as Substrate on the Quality and Yield of Mushrooms

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Food and Nutrition Sciences 2011年第7期2卷 780-784页

作者： Mercy Badu Sylvester K. Twumasi Nathaniel O. Boadi 不详

The objective of this study was to find out if the sawdust generated from some of the Ghanaian wood species can be used in the cultivation of pleurotus ostreatus (oyster mushroom) and their subsequent effect on the quality and yield of the mushrooms produced. Sawdust from three Ghanaian wood species (Triplochiton scleraxylon, Ceiba pentandra and Terminalia superba) were collected and their cellulose, hemicelluloses, lignin and nitrogen contents determined using standard methods. Triplochiton scleraxylon gave 46.76%, 15.69%, 27.55%, 0.01% w/w, Ceiba pentandra gave 44.79%, 15.32%, 34.08%, 0.02% w/w and Terminalia superba gave 46.64%, 16.29%, 31.17%, 0.02% w/w of the cellulose, hemicelluloses, lignin and nitrogen content respectively. Compost was then made from each of the wood and used as substrate for the cultivation of pleurotus ostreatus. The highest yield of mushroom was obtained from T. scleraxylon 334g followed by T. superba 277 g and C. pentandra gave the lowest yield of 193 g fresh weight after 3 flushes. The proximate composition of the mushrooms produced gave crude protein ranging 16.33 - 18.20, fat 1.67 - 2.07, carbohydrate 40.86 - 50.53, fibre 4.14 - 6.73 and ash content of 4.40% - 5.80%. The report has shown that the yield and nutritional content of the oyster mushroom on sawdust depends on the chemical constituents such as the cellulose content, the hemicellulose content, the lignin content, the nitrogen content of the particular substrate used. Triplochiton scleraxylon gave the best yield and nutritional content, considering that these substrates are freely available and regarded as “waste”, it can be used to cultivate edible mushrooms to supplement nutritional requirement and source of income to make life better for many people.

关键词： Lignin Cellulose hemicellulose Proximate Composition Pleurotus Ostreatus

The role of cell wall in plant responses to nutritional stresses

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The role of cell wall in plant responses to nutritional stre...