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Paper And Biomaterials 2021年第1期6卷 1-10页

作者： Xiaoqi Gong Zongwei Zhang Yonghao Ni Xinhua Ouyang Lihui Chen Liulian Huang Huichao Hu College of Material Engineering Fujian Agriculture and Forestry UniversityFuzhouFujian Province350002China Department of Chemical Engineering University of New BrunswickFrederictonNew BrunswickE3B 5A3Canada

Hemicellulose has a wide range of applications,including that as an emulsifier for the food industry and raw material for the synthesis of bioethanol/biochemicals and biodegradable *** is usually present as a spent liquor,such as the prehydrolysis liquor of the prehydrolysis kraft dissolving pulp production process and the alkali extraction liquor of the cold caustic extraction of pulp *** to its dilute nature,hemicellulose needs to be dried for practical utilization,and this is *** this study,cellulose and hemicellulose in a bleached bamboo kraft pulp were separated using an alkali extraction *** obtained from the extraction liquor was dried by an ammonium carbonate-assisted drying *** effects of drying time and drying temperature were *** of the hemicellulose obtained by the ammonium carbonate-assisted drying process was similar to that of original hemicellulose,as revealed by detailed Fourier transform infrared and X-ray diffraction *** novel drying method was more energy efficient and required a shorter drying time than the conventional freeze drying method,and the excellent solubility in alkaline solutions favored the chemical modification of *** dried hemicellulose can be used as a renewable raw material for the preparation of hydrogels and other substances such as bioethanol/biochemicals and biodegradable films.

关键词： bamboo kraft pulp hemicellulose alkali extraction ammonium carbonate drying process dissolving pulp

Effect of alkali extraction on pit membranes and liquid uptake of four commercial softwoods

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Forestry Studies in China 2012年第2期14卷 160-164页

作者： WANGYue WANGMing-zhi DepartmentofNaturalResourcesandEco—materials GraduateSchoolofAgricultureTokyoUniversityofAgricultureandTechnol—ogyFuchuTokyo183—8509Japan DepartmentofWoodScienceandTechnology CollegeofMaterialsScienceandTechnologyBeijingForestryUniversityBeijing100083．P．R．China

The present study examined the effect of alkali extraction on pit membranes （PMs） and liquid uptake of four conifers. Af- ter alkali extraction, the deposits around the PMs almost dissolved in Cunninghamia lanceolata Hook. and Cryptomeriajaponica D. Don wood which showed good liquid uptake. In contrast, in Larix leptolepis Gordon and Pseudotsuga menziesii Franco, although the tori adhered strongly to the pit aperture preventing liquid transportation, the liquid uptake of the woods improved markedly. More- over, the combined treatment of alkali extraction-transverse compression had no synergistic effect in improving liquid uptake. These results demonstrate that alkali extraction is effective in improving the liquid uptake of wood.

关键词： pit membrane alkali extraction liquid uptake

Fibrous Fractionation of Cocoa Pod Husks alkali extraction

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Fibrous Fractionation of Cocoa Pod Husks Alkali Extraction

Structural characterization of three acidic polysaccharides from Opuntia dillenii *** and their protective effect against hydrogen peroxide-induced oxidative stress in Huh-7 cells

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

来源： cnki会议评论

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Food Science and Human Wellness 2024年第4期13卷 1929-1942页

作者： Rui Liu Fangxin Chu Zheng Yan Hanqing Chen School of Food and Biological Engineering Hefei University of TechnologyHefei 230601China Engineering Research Center of Bio-Process Ministry of EducationHefei University of TechnologyHefei 230601China

Three novel acidic polysaccharide fractions(OFPP-1,OFPP-2,OFPP-3)with different m olecular weights(803.7,555.1 and 414.5 k Da)were isolated from the peeled Opuntia dillenii *** by alkali-extraction,graded alcohol precipitation and column *** analysis indicated that OFPPs were pectic polysaccharides consisting of rhamnose,arabinose and galactose *** backbone of OFPP-1 consisted of a repeating unit→6-α-D-Galp A-(1→2)-α-L-Rhap-(1→with T-α-D-Galp A-(1→6)-α-D-Galp A-(1→4)-α-D-Glcp-(1→,T-β-D-Xylp-(1→6)-α-D-Galp A-(1→4)-α-D-Glcp-(1→or T-α-D-Galp A-(1→3)-α-L-Araf-(1→as the side *** backbone of OFPP-2 consisted of a disaccharide repeating unit→2)-α-L-Rhap-(1→4)-β-D-Galp A-(1→with T-β-L-Araf-(1→as the branches substituted at the O-4 position of→2,4)-α-LRhap-(1→.Whereas the backbone of OFPP-3 was→2,4)-α-L-Rhap-(1→2)-α-L-Rhap-(1→3)-β-L-Araf-(1→or→2,4)-α-L-Rhap-(1→2)-α-L-Rhap-(1→4)-β-D-Galp A-(1→,which was branched at the O-4 position of→2,4)-α-L-Rhap-(1→.Moreover,these three polysaccharide fractions could protect Huh-7 cells against H2O2-induced oxidative stress to different extents by decreasing the MDA content and increasing the SOD,CAT,GSH-Px activities and the GSH level in the Huh-7 *** results suggest that OFPPs have the potential to be used as natural antioxidants.

关键词： Opuntia dillenii Haw.fruits Polysaccharide alkali extraction Structural characterization Oxidative stress

Isolation of Hemicellulose from Wood Chips via extraction with Kraft Green Liquor

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Chemical Research in Chinese Universities 2010年第4期26卷 667-671页

作者： SUN Hui XU Ying-kai XU Guo-zhi Department of Material Science and Engineering China National Center for Quality Supervison ＆ Test of Plastic Products Beo＇ing Technology and Business University Beijing 100048 P. R. China Department of Surgery University of Pittsburg 3459 Fifth Avenue Pittsburgh PA USA

The present paper covers the extraction of hemicelluloses from woods, i.e., Eucalyptus Globulus, white fir and Douglas fir via green liquor pretreatment and alkali post-treatment with sodium hydroxide. The effects of such extraction conditions as extraction time, temperature on the yields of hemicellulose and the degree of deliginification were investigated. Sugar analyses using Dionex indicate that xylose, glucose and mannose are the main sugar types present in the hemicellulose from Eucalyptus. Other sugar components such as arabinose and galactose were also found in Dogulas fir hemicellulose. The highest yield of hemicellulose was 8.4% for Eucalyptus extracted with green liquor at 130 ℃ for 3.5 h. Further sodium hydroxide extraction for 5 h gave a hemicellulose yield of about 20%. The use of green liquor for the extraction of wood hemicellulose is believed to be the first attempt.

关键词： Hemicellulose Lignin Wood Green liquor alkali extraction