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Extraction and Characterization of PHB from Acidiphilium cryptum DX1-1 被引量:2
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作者 徐爱玲 夏金兰 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第6期938-943,共6页
A new bacterial strain,was designated as strain Acidiphilium cryptum DX1-1,accumulates intracellular poly-β-hydroxybutyrate particles,four methods which have advantages and disadvantages for each were employed to ext... A new bacterial strain,was designated as strain Acidiphilium cryptum DX1-1,accumulates intracellular poly-β-hydroxybutyrate particles,four methods which have advantages and disadvantages for each were employed to extract PHB.Chloroform-sodium hypochlorite method is the best in extracting PHB form Acidiphilium cryptum DX1-1.The extraction rate reaches 73%,the purification rate is 92% and molecular weight is 326 kg/mol.Then the PHB extracted by this method was analyzed by ultraviolet-visible absorption spectroscopy,fourier transform infrared(FT-IR) and nuclear magnetic resonance(NMR).The results show that PHB from strain DX1-1 has the same biochemical structure and character with PHB standard.Mass spectrometer(MS) analysis reveals that the long chain of PHB is destroyed when treated by chloroform-sodium hypochlorite.The differential scanning calorimetry(DSC) of PHB shows PHB from Acidiphilium cryptum DX1-1 has low degree of crystallinity which makes the PHB has a wider range of applications. 展开更多
关键词 Acidiphilium cryptum PHB extractION characterIZATION
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Organic matter extracted from activated sludge with ammonium hydroxide and its characterization 被引量:1
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作者 Liangliang Wei Kun Wang +3 位作者 Qingliang Zhao Junqiu Jiang Chunmei Xie Wei Qiu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第5期641-647,共7页
In order to characterize the organic properties of waste activated sludge in a wastewater treatment plant,organic matter within sludge was extracted with NH 3 ·H 2 O preferentially,and subsequently fractionated i... In order to characterize the organic properties of waste activated sludge in a wastewater treatment plant,organic matter within sludge was extracted with NH 3 ·H 2 O preferentially,and subsequently fractionated into five fractions using XAD-8/XAD-4 resins.Up to a 63.8%-71.1% of organic matter within the sludge could be efficiently extracted by NH 3 ·H 2 O.Fractionation results showed that hydrophobic acid and hydrophilic fraction were two main components among the sludge organic matter (accounting for 32.2% and 48.0% of the bulk organic matter,respectively),whereas transphilic acid,hydrophobic neutral and transphilic neutral were quite low (accounting for 9.2%,5.8% and 4.8%,respectively).Despite that the extractant of NH 3 ·H 2 O showed a relatively higher extraction efficiency of the aromatic components,the relatively low aromaticity of the organic fractions implied that those non-aromatic components could also be effectively extracted,especially for neutral and hydrophilic fractions.In addition,acidic fractions contained more aromatic humic-like components,whereas the neutral fractions had a greater content of aromatic proteins and soluble microbial byproduct-like components.Extraction of sludge organics with NH3·H2O and subsequential fractionation using XAD resins could be a novel method for further characterization of sludge organics. 展开更多
关键词 sludge organic matter extraction FRACTIONATION characterIZATION
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Traditional Pathway of Oil Extraction from <i>Quassia undulate</i>Seeds and Its Chemical Characteristic 被引量:1
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作者 Ndiaye Seyni Gueye Mathieu +2 位作者 Baldé Samba Ndiaye Bou Ayessou Nicolas Cyrille 《Food and Nutrition Sciences》 2021年第5期452-461,共10页
In Africa, traditional vegetable oil extraction often involves the use of plants in the manufacturing process. <span style="font-family:Verdana;"><span style="font-family:Verdana;"><... In Africa, traditional vegetable oil extraction often involves the use of plants in the manufacturing process. <span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Quassia undulate</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> oil is thus traditionally prepared. An expedition went to Kédougo (a region in southeastern Senegal involving women of the Bassaris community) in June 2018 to study the </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Q</span></i></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">.</span><i><span style="font-family:Verdana;"> undulate</span></i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> oil traditional extraction mode. Thus, the objective of this study is to follow the traditional extraction of </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Q</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span><span><span><i><span style="font-family:;" "=""> </span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">undulate</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> oil and to perform the physico-chemical analysis of the obtained oil. Oil samples taken after the survey allowed the oil physico-chemical characterization. The traditional oil extraction made by four women from Eganga, Ethiolo, and Ebarack’s villages reveals oil clear that is solid at room temperature. The study of the established chart revealed the use of </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Pilliostigma</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> <i>thonnintigi</i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> leaves during the oil preparation. The oil shows characteristics comparable to shea butter, and the oil stability can be compared to the corn and peanut oil one. The physicochemical analysis showed oil solid at room temperature with an acid value between </span><span style="font-family:Verdana;">1.223 ± 0.013 and 7.333 ± 0.465. The saponification value was between</span><span style="font-family:Verdana;"> 190.489 ± 3.083 and 199.732 ± 3.107, and the peroxide value between 4.453 ± 0.042 and 8.644 ± 0.285. The iodine value</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> were between 21.455 ± 2.440 and 38.068 ± 0.082, and the refractive index 1.462 - 1.463. </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Q</span></i></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">.</span><i><span style="font-family:Verdana;"> undulate</span></i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> oil offers several technological perspectives. However, it would be interesting to study the impact of </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">P</span></i></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">.</span><i><span style="font-family:Verdana;"> thonnintigi</span></i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> leaves during extraction. The fatty acid profile should also be determined.</span></span></span> 展开更多
关键词 Quassia undulate Traditional extraction Physico-Chemical characterization
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Extraction and Characterization of Bagasse Fibres from Sugar Cane (<i>Saccharum officinarum</i>) for Incorporation into a Mortar
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作者 Tchotang Theodore Carlos Mozer +4 位作者 Pondi Joseph Jeme Njie Nfor Clins Ze Eric Parfait Souck Joseph Loic 《Open Journal of Applied Sciences》 2020年第8期521-533,共13页
The paper reported a comparative study of the methods of extraction of <span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;&qu... The paper reported a comparative study of the methods of extraction of <span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">vegetable fibres encountered in the literature;three main ones was chose, namely: combing, retting with pre-treatment of the bagasse in salt and distilled water,</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">and Chemical extraction at three concentration levels of soda (2N, 1N, 0.1N) </span><span style="font-family:Verdana;">with pre-treatment of bagasse with salt water and distilled water. After extracting the fibres using these methods, it appeared that the natural methods (retting and combing) have a higher yield of around 70% compared to the</span><span style="font-family:Verdana;"> chemical method which has a low yield of around 40%. The fibres obtained by the chemical extraction method (1N-BPD) had the best characteristics</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span> 展开更多
关键词 BAGASSE characterIZATION ELABORATION extractION Fibre
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Physicochemical characterization of Baizhi particles by ultrafine pulverization 被引量:3
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作者 Lian-wei Yang Peng Sun +2 位作者 Guo-sheng Gai Yu-fen Yang Yu-rong Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2011年第2期247-251,共5页
Baizhi, as a medicinal plant, has been demonstrated to be useful for the treatment of aches and pains in China. The physicochemical characterization of Baizhi particles is greatly influenced by ultrafine pulverization... Baizhi, as a medicinal plant, has been demonstrated to be useful for the treatment of aches and pains in China. The physicochemical characterization of Baizhi particles is greatly influenced by ultrafine pulverization. To study the physicochemical characterization of Baizhi, the raw plant material of Baizhi was ground to 6 μm particles by a high speed centrifugal sheering (HSCS) pulverizer. The micron particles were characterized by optical microscopy and scanning electron microscopy (SEM). Imperatorin is one of the active ingredients of Baizhi, and its extraction yield is determined to evaluate the chemical characterization of Baizhi powder. Imperatorin was analyzed by high performance liquid chromatography (HPLC). The results show that after ultrafine pulverization, the plant cell walls are broken into pieces and the extraction yield of imperatorin is increased by 11.93% compared with the normal particles. 展开更多
关键词 Baizhi physicochemical characterization PULVERIZATION IMPERATORIN extractION
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Authentication of <i>Rothmannia whitfieldii</i>Dye Extract with FTIR Spectroscopy 被引量:1
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作者 Onyekachi Onyinyechi Nnorom Genevive Chinyere Onuegbu 《Journal of Textile Science and Technology》 2019年第2期38-47,共10页
Extraction of dye from dry fruit of Rothmannia whitfieldii was carried out using four different extraction methods. Solvent and acid extraction methods gave a colourless supernatant solution after extraction time of 4... Extraction of dye from dry fruit of Rothmannia whitfieldii was carried out using four different extraction methods. Solvent and acid extraction methods gave a colourless supernatant solution after extraction time of 45 minutes at 60°C. The alkali method gave a deep brown coloured supernatant solution while the aqueous method gave a dark coloured supernatant solution after extraction under the same conditions. From the result of the FTIR spectroscopy characterization of the coloured solutions and the dry powder of Rothmannia whitfieldii fruit, it was observed that only the alkali method extracted what can be called a dye with likely presence of tannins. The result also showed that the possible functional groups present in the supernatant solution after aqueous extraction are same with the functional groups present in the dry pulverized Rothmannia whitfieldii fruit. Hence, aqueous method did not extract any dye. Similarly, a mixture of the solution after aqueous extraction with drops of alkali solution produced a deep brown coloured solution indicating solubility of the dye component in alkali media. 展开更多
关键词 characterization extraction FTIR Spectroscopy Natural DYE Rothmannia whitfieldii SUPERNATANT Solution
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Chemical composition and antioxidant capacity of the aqueous extract of Phellodendron amurense 被引量:4
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作者 Natarajan Velmurugan Duraisamy Kalpana +1 位作者 Jae Young Cho Yang Soo Lee 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第4期1033-1040,共8页
The aqueous extract of Phellodendron amurense Rupr. (Amur Cork Tree) provides a rich source of antioxidants and chemical compounds, and can be used for food and wood preservative materials. In this study, we charact... The aqueous extract of Phellodendron amurense Rupr. (Amur Cork Tree) provides a rich source of antioxidants and chemical compounds, and can be used for food and wood preservative materials. In this study, we characterized the chemical composition of this extract by GC and GC/MS. The antioxidant capacity was evaluated using a variety of antioxidant assays (superoxide radical, hydroxyl radical, nitric oxide radical, and DPPH radical scavenging activity). Additionally, total polyphenolic content was determined. Phenolic acids and acetone derivatives were major compounds of the extract capable of scavenging the DPPH free radical and reducing ferric ions. DPPH and ferric ion reduction results were strongly correlated with total phenolic content of the extract which also exhibited strong nitric oxide, hydroxyl radical scavenging and superoxide anion radical scavenging activities. 展开更多
关键词 Phellodendron amurense Aqueous extract Chemical characterization Antioxidant activity
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Largescale Preparation of Organic-Dispersible Lanthanide Fluorides Nanocrystals via Colloid-Extraction Route 被引量:1
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作者 赵委婉 张晟卯 +2 位作者 贺本芳 吴志申 张治军 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第S2期22-26,共5页
Organic-dispersible lanthanide fluorides nanocrystals were synthesized at a large scale using colloid-extraction method, in the presence of dialkyl-dithiophosphinic acid (DDPA) as the extraction agent. The products we... Organic-dispersible lanthanide fluorides nanocrystals were synthesized at a large scale using colloid-extraction method, in the presence of dialkyl-dithiophosphinic acid (DDPA) as the extraction agent. The products were characterized by means of X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier transformation infrared (FTIR) spectroscopy. It was found that the synthesized lanthanide fluorides nanoparticles had high purity and crystallinity, and could be well dispersed in organic solvents such as chloroform, toluene etc., which could be closely related to the surface-capping of the nanocrystals by the DDPA molecules. Moreover, the nanocrystals before and after extraction by DDPA showed few differences in the microscopic morphologies. It was implied that DDPA as the extraction agent had good protection to the nanocrystals as well, which could be essential to the commercial application of the titled rare earth nanocrystals as novel multifunctional additives in the fields of lubrication. 展开更多
关键词 lanthanide fluorides NANOCRYSTALS colloid-extraction largescale production characterization rare earths
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Three-dimensional analysis technology for accurately characterizing non-metallic inclusion particles in steel 被引量:1
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作者 ZHANG Yi CHEN Jinming +2 位作者 MIAO Lede WANG Guodong WU Junfei 《Baosteel Technical Research》 CAS 2011年第4期40-48,共9页
In this paper, a kind of three-dimensional analysis technology for characterizing non-metallic inclusions in steel was clearly elaborated. It is an electron microscopy observation, namely the non-aqueous electrolysis ... In this paper, a kind of three-dimensional analysis technology for characterizing non-metallic inclusions in steel was clearly elaborated. It is an electron microscopy observation, namely the non-aqueous electrolysis extraction method with a settled coulometer. In the research,the extraction effects of non-metallic inclusions in different electrolysis systems were studied, and it was concluded that alkalescent 2% TEA non-aqueous electrolyte was applicable for extracting most of non-metallic inclusion particles in steel. And then, in order to ensure the microscopic characterization and statistical calculation of inclusion particles, some electrolysis parameters should be confirmed, such as the size of the sample, control of the electrolysis mass, electric current, etc. Furthermore, for preventing the disturbance of carbides and presenting clear three-dimensional appearance by microscopic characterization, magnetic separation was utilized to separate the inclusion particles from carbides, which was useful for getting more veracious types, particle sizes and chemical composition of inclusions. Moreover, through calculation of quantity and particle size of inclusions in continuous determinate fields, the total quantity per unit volume or area and the particle size distribution of inclusions could be acquired by conversion with electrolysis loss. Besides, the comparison between this method and traditional quantitative metallography was also discussed, and finally, a conclusion was drawn that both of them have respectively applications in characterizing inclusions. 展开更多
关键词 non-metallic inclusion non-aqueous electrolytic extraction SEM microscopic characterization
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风化煤腐植酸的提取应用研究进展 被引量:1
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作者 马力通 李丽萍 刘玉龙 《化学与生物工程》 CAS 北大核心 2024年第2期7-12,37,共7页
风化煤含氧量高、发热量低使其失去了作为燃料的价值,作为煤炭资源衍生而来的矿产资源,没有发挥出最大经济价值。但是,风化煤富含腐植酸,可以制备高附加值腐植酸,进而应用于工业、农业等领域。基于风化煤的化学性质和特点,简单介绍了风... 风化煤含氧量高、发热量低使其失去了作为燃料的价值,作为煤炭资源衍生而来的矿产资源,没有发挥出最大经济价值。但是,风化煤富含腐植酸,可以制备高附加值腐植酸,进而应用于工业、农业等领域。基于风化煤的化学性质和特点,简单介绍了风化煤腐植酸的结构表征方法,对风化煤的预处理方法及碱溶酸析法、催化法、微生物溶解法、絮凝法、序贯溶解法等腐植酸提取方法进行了综述,介绍了风化煤腐植酸的应用研究进展,并提出了风化煤腐植酸提取新工艺的研究方向,为推动风化煤资源的高附加值利用奠定了基础。 展开更多
关键词 风化煤 腐植酸 提取 表征方法 应用
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宁夏枸杞酚类及其衍生物的研究与应用进展 被引量:1
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作者 马茜 张渌淘 +6 位作者 禄璐 金波 刘菲 李应萍 车章斌 米佳 闫亚美 《食品科学》 EI CAS CSCD 北大核心 2024年第17期316-325,共10页
酚类化合物是植物中重要的一类次生代谢物,具有多种生物活性,被认为是营养、功能食品的主要功效成分。宁夏枸杞(Lycium barbarum L.)作为重要的药食同源滋补品,富含酚类化合物及其衍生物。本文综述了国内外宁夏枸杞酚类化合物及其衍生... 酚类化合物是植物中重要的一类次生代谢物,具有多种生物活性,被认为是营养、功能食品的主要功效成分。宁夏枸杞(Lycium barbarum L.)作为重要的药食同源滋补品,富含酚类化合物及其衍生物。本文综述了国内外宁夏枸杞酚类化合物及其衍生物的研究进展,包括宁夏枸杞酚类化合物的提取、分离、分析与鉴定方法及生物活性;同时也总结了酚类物质对枸杞食药风味/五味的贡献、合成代谢及其深加工应用研究进展,并对枸杞酚类化合物研发存在的问题提出建议及展望。以期为宁夏枸杞酚类及其衍生物的深入研究提供参考依据,为特色资源枸杞开发利用提供理论指导。 展开更多
关键词 宁夏枸杞 酚类化合物 提取 分离 结构表征 加工应用
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贝母多糖提取纯化、结构表征及生物活性研究进展 被引量:1
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作者 李少华 龙娇妍 秦令祥 《饲料工业》 CAS 北大核心 2024年第10期127-132,共6页
贝母是一种具有数千年历史的药食两用的中药材,含有多种活性成分,如皂苷、生物碱、氨基酸、黄酮类和多糖。其中,贝母多糖具有抗氧化、抗炎、抗衰老、免疫调节等作用,在食品医药领域具有良好应用前景。文章综述了近年来国内外关于贝母多... 贝母是一种具有数千年历史的药食两用的中药材,含有多种活性成分,如皂苷、生物碱、氨基酸、黄酮类和多糖。其中,贝母多糖具有抗氧化、抗炎、抗衰老、免疫调节等作用,在食品医药领域具有良好应用前景。文章综述了近年来国内外关于贝母多糖的研究现状,比较了贝母多糖不同提取纯化方法的优缺点,探讨贝母多糖结构与其生物活性的关系,分析贝母多糖研究的发展趋势及在畜禽养殖中的应用前景,为贝母多糖的研究和开发利用提供一定参考依据。 展开更多
关键词 贝母 多糖 提取纯化 结构解析 生物活性
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Antioxidant Activity of Cosmetic Formulations Based on Novel Extracts from Seeds of Brazilian <i>Araucaria angustifolia</i>(Bertoll) Kuntze
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作者 Gabriela Sprada Tavares da Mota Angela Bonjorno Arantes +5 位作者 Gianni Sacchetti Antonella Spagnoletti Paola Ziosi Emanuela Scalambra Silvia Vertuani Stefano Manfredini 《Journal of Cosmetics, Dermatological Sciences and Applications》 2014年第3期190-202,共13页
The process of oxidation, due to free radicals, is the cause of major concern for human health. In particular damages related to the skin have great relevance;therefore, many antioxidants based products are developed ... The process of oxidation, due to free radicals, is the cause of major concern for human health. In particular damages related to the skin have great relevance;therefore, many antioxidants based products are developed and marketed with the intention to counteract the action of free radicals. The seed of Araucaria angustifolia is a rich source of antioxidants due to the presence of bioflavonoids to counteract free radicals damages. In this study, two extracts, one from the seed external teguments (shell) and the other from the inner seed pulp (endosperm and embryo) were obtained in order to evaluate possible applications to the dermo-cosmetic field. In parallel the following different methods were employed to characterize both the extracts and to determine their antioxidant capacity: HPTLC, ABTS and DPPH, ORAC and PLC. The qualitative analysis showed that both extracts have the antioxidant activity, but the quantitative evaluation revealed a more promising bioactivity from the shell than from the pulp. Therefore, it was evaluated the potential skin application of different cosmetic formulations, based on the presence of seed shell extract (W/O emulsion, O/W emulsion and gel). The best result was achieved with the W/O emulsion. 展开更多
关键词 ARAUCARIA angustifolia Sustainability Seed Alcoholic extractS Antioxidant Activity characterization HPTLC ORAC PCL
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两种不同产地锁阳多糖组分的结构解析及体外抗氧化活性对比研究
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作者 牧丹 Munkhtsetseg Baatar +3 位作者 Ulziijargal Nanzad 张曼 赵鹏 苏日娜 《中国食品添加剂》 CAS 2024年第9期25-33,共9页
研究两种不同产地锁阳多糖的组成及初级结构,并探讨体外抗氧化活性。利用水提醇沉法提取粗多糖,采用红外分光光度法、离子色谱法、高效凝胶色谱法等对样品进行初级结构解析、单糖组成及分子量的测定;并测定其体外抗氧化活性。结果显示,... 研究两种不同产地锁阳多糖的组成及初级结构,并探讨体外抗氧化活性。利用水提醇沉法提取粗多糖,采用红外分光光度法、离子色谱法、高效凝胶色谱法等对样品进行初级结构解析、单糖组成及分子量的测定;并测定其体外抗氧化活性。结果显示,苏尼特粗多糖中总糖含量(49.65%)比阿拉善粗多糖中总糖含量(35.44%)略高。苏尼特右旗锁阳TCA法脱蛋白多糖及阿拉善锁阳TCA法脱蛋白多糖的重均分子量分别为56.131、50.696kDa,两种脱蛋白多糖中单糖组成没有明显区别。在一定浓度范围之内均有一定的体外抗氧化活性,并呈质量浓度依赖关系。研究发现,苏尼特右旗产锁阳中多糖含量比阿拉善产锁阳高,分子量、单糖组成及抗氧化活性等方面没有明显差异。本研究可为锁阳及其它类似药材中多糖的提取、纯化及药理活性研究提供参考。 展开更多
关键词 锁阳多糖 提取纯化 结构表征 抗氧化活性
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大鲵骨酸溶性和胃蛋白酶溶性胶原蛋白的提取与表征 被引量:1
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作者 宫萱 包建强 +2 位作者 黄可承 陈彦婕 唐嘉诚 《中国食品学报》 EI CAS CSCD 北大核心 2024年第3期268-275,共8页
大鲵为一种珍贵的两栖动物,营养丰富。为了充分且有效利用其加工副产物,分离并表征了来自大鲵骨的酸溶性胶原蛋白(ASC)和胃蛋白酶溶解性胶原蛋白(PSC)。大鲵骨ASC和PSC的产率分别为10.71%和13.11%。通过傅里叶红外光谱揭示胶原蛋白稳定... 大鲵为一种珍贵的两栖动物,营养丰富。为了充分且有效利用其加工副产物,分离并表征了来自大鲵骨的酸溶性胶原蛋白(ASC)和胃蛋白酶溶解性胶原蛋白(PSC)。大鲵骨ASC和PSC的产率分别为10.71%和13.11%。通过傅里叶红外光谱揭示胶原蛋白稳定的三螺旋结构。SDS-PAGE电泳图显示两个样品均为I型胶原蛋白,同时具有高水平的亚氨基酸(179~187/1000个残基)。样品在pH 6时溶解度最高。热变性温度(45.78~46.51℃)显著高于海洋和淡水鱼物种。在SEM下,胶原蛋白显示出致密的片状和不规则的孔洞状。这些结果表明大鲵骨胶原蛋白特性与哺乳动物胶原蛋白相似,具有成为其替代品的潜力,为其后续的研究和开发利用提供了基础数据。 展开更多
关键词 大鲵骨 胶原蛋白 提取 表征
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白丁香花多糖的提取、纯化及抗氧化活性研究 被引量:1
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作者 王天怡 张庆芬 +2 位作者 黄磊磊 刘佳怡 杨逢建 《食品工业科技》 CAS 北大核心 2024年第15期233-243,共11页
采用酶辅助超声提取法提取白丁香花多糖,利用响应面试验(RSM)法系统分析了不同实验条件对白丁香花多糖得率的影响。将粗多糖经DEAE-52纤维素柱和Sephadex G-100凝胶柱层析进行纯化,用高效凝胶渗透色谱法(HPGPC)、离子色谱法(IC)、紫外... 采用酶辅助超声提取法提取白丁香花多糖,利用响应面试验(RSM)法系统分析了不同实验条件对白丁香花多糖得率的影响。将粗多糖经DEAE-52纤维素柱和Sephadex G-100凝胶柱层析进行纯化,用高效凝胶渗透色谱法(HPGPC)、离子色谱法(IC)、紫外光谱、傅里叶红外光谱(FTIR)和扫描电镜(SEM)对多糖的初步结构进行了表征,并进行体外抗氧化活性研究。结果表明,白丁香花多糖最佳提取工艺:超声功率150 W、超声时间40 min、超声温度40℃、加酶量(纤维素酶、中性蛋白酶)2.2%、料液比1:40 g/mL,在此条件下白丁香花多糖的得率为3.03%±0.09%。经DEAE-52纤维素柱纯化后得到4个组分的多糖,收集主要组分SP-c;再经Sephadex G-100凝胶柱纯化后得到SP-c-1组分。得出SP-c-1的单糖组成及摩尔比为半乳糖醛酸、阿拉伯糖、半乳糖、鼠李糖、葡萄糖、葡萄糖醛酸、木糖=18.39:11.13:8.96:2.61:1:0.83:0.57。SP-c-1重均分子量(Mw)为14069 Da,数均分子量(Mn)为13637 Da,具有多糖特征吸收峰,含D-葡萄吡喃糖构型。SP-c-1对DPPH、ABTS+自由基的半抑制浓度(IC_(50))分别0.87、1.355 mg/mL。SP-c-1显示出良好的抗氧化活性。 展开更多
关键词 白丁香花 多糖 结构表征 酶辅助超声提取 抗氧化活性
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生姜多糖的提取及抗氧化作用研究
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作者 孟宪伟 罗亮 +4 位作者 孙源 赵志刚 王世会 张瑞 郭坤 《安徽农业科学》 CAS 2024年第11期149-153,共5页
采用超声辅助提取法从生姜中提取多糖,采用单因素和正交试验对生姜多糖提取工艺进行优化,结果发现:生姜多糖最佳提取工艺为液料比1∶20,匀浆时间5 min,匀浆温度70℃,超声时间80 min为宜,超声温度80℃,超声波功率为100 W,在该条件下多糖... 采用超声辅助提取法从生姜中提取多糖,采用单因素和正交试验对生姜多糖提取工艺进行优化,结果发现:生姜多糖最佳提取工艺为液料比1∶20,匀浆时间5 min,匀浆温度70℃,超声时间80 min为宜,超声温度80℃,超声波功率为100 W,在该条件下多糖得率为12.56%。抗氧化活性测定结果表明,生姜多糖在5 mg/mL时对羟基自由基的清除能力可达到90.96%,且还原力最强。 展开更多
关键词 生姜多糖 提取 结构表征 抗氧化作用
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活塞-缸套摩擦副状态表征参数选取方法研究
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作者 魏敬宏 纪少波 +3 位作者 胡珑渝 张珂 张志鹏 姜颖 《内燃机工程》 CAS CSCD 北大核心 2024年第2期75-84,共10页
建立柴油机试验台架采集数据,对机体表面振动信号进行时频分析,探明不同激励源与机体表面振动信号的关系。选取变分模态分解(variational mode decomposition,VMD)算法对振动信号进行分解,提取各分量的表征参数。通过探究转矩、转速、... 建立柴油机试验台架采集数据,对机体表面振动信号进行时频分析,探明不同激励源与机体表面振动信号的关系。选取变分模态分解(variational mode decomposition,VMD)算法对振动信号进行分解,提取各分量的表征参数。通过探究转矩、转速、润滑油温度及配缸间隙与各表征参数的相关性,初步确定相关性强的表征参数集。通过多评价准则对上述表征参数集进行分析,最终得出贡献度最高的表征参数为本征模态函数(intrinsic mode function,IMF)1的标准差、均方频率、峭度、最大奇异值、频域积分和IMF6的脉冲因子、标准差、重心频率、频率方差及最大奇异值。 展开更多
关键词 活塞–缸套 故障诊断 表征参数提取 连续小波变换 信号分解算法 多评价准则
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西瓜皮中3种多糖的初步表征及抗氧化活性对比
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作者 刘盈 张欣 +4 位作者 刘会平 王兵 马笑笑 张慧慧 李灿 《食品研究与开发》 CAS 2024年第4期110-117,共8页
该研究使用水提醇沉法从西瓜皮(Exocarpium Citrulli)中提取3种不同结构的多糖,并对比它们的体外抗氧化活性,采用DEAE-52纤维素柱和Sephadex G-200层析柱对西瓜皮多糖进行分离纯化得到相对分子质量不同的3种多糖并命名为ECP-1、ECP-2和E... 该研究使用水提醇沉法从西瓜皮(Exocarpium Citrulli)中提取3种不同结构的多糖,并对比它们的体外抗氧化活性,采用DEAE-52纤维素柱和Sephadex G-200层析柱对西瓜皮多糖进行分离纯化得到相对分子质量不同的3种多糖并命名为ECP-1、ECP-2和ECP-3,使用离子色谱、红外光谱、扫描电子显微镜、刚果红实验、热重(thermal gravimetric analyzer,TGA)等进行分析。结果表明:3种多糖均为水溶性大分子多糖。ECP-3的自由基清除能力高于另外两种酸性多糖,这可能与ECP-3含有较高的糖醛酸有关。 展开更多
关键词 西瓜皮 多糖 提取 纯化 结构表征 抗氧化活性
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植物染料结构、提取方法及表征手段研究
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作者 李双双 卢凯亮 张维 《针织工业》 北大核心 2024年第10期87-92,共6页
染整加工是赋予纺织品高附加值的关键环节,正朝着绿色、环保、可持续的方向发展。天然植物染料因具有环境友好、可生物降解、可将染色织物功能化等特点,备受行业关注。文章从纺织品染色用天然植物染料的分类及化学结构分析出发,以研究... 染整加工是赋予纺织品高附加值的关键环节,正朝着绿色、环保、可持续的方向发展。天然植物染料因具有环境友好、可生物降解、可将染色织物功能化等特点,备受行业关注。文章从纺织品染色用天然植物染料的分类及化学结构分析出发,以研究成果案例为中心,重点叙述植物染料的提取方法、优势和特点,并围绕实际染色过程需要,对天然植物染料的表征手段进行综合阐述,为天然植物染料的应用和开发提供借鉴和参考。 展开更多
关键词 天然植物染料 纺织品染色 提取方法 表征手段 研究进展
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