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Separation of methyl linolenate and its analogues by functional mixture of imidazolium based ionic liquid-organic solvent-cuprous salt 被引量:1
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作者 Xianghong Lu Jiajian Zhu +1 位作者 Xing Qian Jianbing Ji 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第4期811-817,共7页
Methyl linolenate was separated from its analogues by a new extraction system constructed by solvent,imidazolium based ionic liquids and cuprous salt. Firstly, the effect of ionic liquid on the dissolution of CuCl in ... Methyl linolenate was separated from its analogues by a new extraction system constructed by solvent,imidazolium based ionic liquids and cuprous salt. Firstly, the effect of ionic liquid on the dissolution of CuCl in acetonitrile, N,N-dimethylformamide(DMF), methanol and water was evaluated by visual observation.[C4Mim][Cl]can improve the dissolution of CuCl in acetonitrile. Then, for the new system as acetonitrile-ILs-CuCl, extraction equilibrium, distribution ratio and selectivity of methyl linolenate and its analogues were determined by gas chromatography analysis and the mass balance. The extraction time, IL structures and CuCl concentrations were investigated. Distribution ratio decreased slightly, but selectivity increased significantly with the addition of CuCl,[C4Mim][Cl] or [C4Vim][NTF2] into acetonitrile.[C4Vim][NTF2] had higher selectivity than [C4Mim][Cl].But the selectivity of the system combining CuCl with [C4Vim][NTF2] was much lower than with [C4 Mim][Cl].For the CuCl-[C4Mim][Cl]-acetonitrile, the extraction efficiency was better than CuCl-acetonitrile, increasing Cu^+ concentration effectively improved the separation selectivity when ratio of CuCl/[C4Mim][Cl] was less than 1. Compared with previous aqueous AgNO3 extractions, the method of using CuCl is a much cheaper and practical way to enrich unsaturated fatty acid. 展开更多
关键词 METHYL linolenate Cuprous SALT Ionic liquid COSOLVENT Extraction
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Landscape of Sequence Variations in Homologous Copies of FAD2 and FAD3 in Rapeseed(Brassica napus L.)Germplasm with High/Low Linolenic Acid Trait
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作者 Haoxue Wu Xiaohan Zhang +5 位作者 Xiaoyu Chen Kang Li Aixia Xu Zhen Huang Jungang Dong Chengyu Yu 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第3期627-640,共14页
Genetic manipulation(either restraint or enhancement)of the biosynthesis pathway ofα-linolenic acid(ALA)in seed oil is an important goal in Brassica napus breeding.B.napus is a tetraploid plant whose genome often har... Genetic manipulation(either restraint or enhancement)of the biosynthesis pathway ofα-linolenic acid(ALA)in seed oil is an important goal in Brassica napus breeding.B.napus is a tetraploid plant whose genome often har-bors four and six homologous copies,respectively,of the two fatty acid desaturases FAD2 and FAD3,which con-trol the last two steps of ALA biosynthesis during seed oil accumulation.In this study,we compared their promoters,coding sequences,and expression levels in three high-ALA inbred lines 2006L,R8Q10,and YH25005,a low-ALA line A28,a low-ALA/high-oleic-acid accession SW,and the wildtype ZS11.The expression levels of most FAD2 and FAD3 homologs in the three high-ALA accessions were higher than those in ZS11 and much higher than those in A28 and SW.The three high-ALA accessions shared similar sequences with the pro-moters and CDSs of BnFAD3.C4 and BnFAD3.A3.In A28 and SW,substitution of three amino acid residues in BnFAD2.A5 and BnFAD2.C5,an absence of BnFAD2.C1 locus,and a 549 bp long deletion on the BnFAD3.A3 promoter were detected.The profile of BnFAD2 mutation in the two low-ALA accessions A28 and SW is different from that reported in previous studies.The mutations in BnFAD3 in the high-ALA accessions are reported for thefirst time.In identifying the sites of these mutations,we provide detailed information to aid the design of mole-cular markers for accelerated breeding schemes. 展开更多
关键词 Brassica napus linolenic acid FAD2 FAD3 promoter coding sequences mutation
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TLC Identification and Extraction Process of Rubiasin-1-methyl Ether from Yao Medicine Chuanlianzhu
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作者 Jingrong LU Jiangcun WEI +3 位作者 Xiumei MA Bing QING Meiyan QIU Wen ZHONG 《Medicinal Plant》 2024年第3期35-38,共4页
[Objectives]To establish a thin-layer chromatography(TLC)method for the determination of rubiadin-1-methyl ether in Yao Medicine Chuanlianzhu(Damnacanthus giganteus).[Methods]A silica gel G thin-layer plate was adopte... [Objectives]To establish a thin-layer chromatography(TLC)method for the determination of rubiadin-1-methyl ether in Yao Medicine Chuanlianzhu(Damnacanthus giganteus).[Methods]A silica gel G thin-layer plate was adopted for TLC.Petroleum ether(60-90℃)-chloroform-methanol-water(7:15:3:1)was used as the developing solvent and inspected under ultraviolet lamp(365 nm).The content was determined by Inertsil ODS-3 C 18 column(4.60 mm×250 mm,5μm),mobile phase:acetonitrile-0.2%phosphoric acid gradient elution,detection wavelength 277 nm,flow rate 1.0 mL/min,column temperature 30℃,injection volume 10μL.[Results]The spots of 10 Chuanlianzhu samples from different origins showed the same color at the same position as the control,and the spots were clear and specific.The injection volume of rubiadin-1-methyl ether showed a good linear relationship in the range of 2.90-145μg(R=0.9996).The average recovery rate of rubiadin-1-methyl ether in the low,medium and high dose groups of Yao Medicine Chuanlianzhu was 98.72%,and RSD=1.78%.[Conclusions]This method can effectively identify Yao Medicine Chuanlianzhu medicinal materials and accurately determine the content of rubiadin-1-methyl ether in the medicinal materials.It provides a scientific basis for the development and utilization of Yao Medicine Chuanlianzhu medicinal resources. 展开更多
关键词 Chuanlianzhu THIN-LAYER chromatography (TLC) Extraction process Rubiadin-1-methyl ETHER Content determination
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Preparation of High-Purity Linolenic Acid from Oil of Lithospermum Erythrorhizon by Urea Inclusion and Column Chromatography 被引量:9
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作者 韩喜江 徐平 +3 位作者 孟祥丽 梁志华 张宗双 杨占成 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第1期53-57,共5页
Aim To separate high purity linolenic acid from the oil of Lithospermumerythrorhizon growing in the Northeast of China. Methods Urea inclusion and column chromatographywere used. Results Unsaturated fatty acid was sep... Aim To separate high purity linolenic acid from the oil of Lithospermumerythrorhizon growing in the Northeast of China. Methods Urea inclusion and column chromatographywere used. Results Unsaturated fatty acid was separated, with a purity of 99.30 wt% of linolenicacid. Conclusion The experiment shows excellent reproducibility and high feasibility for industrialproduction. 展开更多
关键词 ltihospermum erythrorhizon linolenic acid urea inclusion columnchromatography
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Preparation and Charaterization of Self-assembled Nanoparticles Based on Linolenic-acid Modified Chitosan 被引量:6
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作者 LIU Chenguang Desai Kashappa Goud H. +1 位作者 CHEN Xiguang Park Hyun-Jin 《Journal of Ocean University of China》 SCIE CAS 2005年第3期234-239,共6页
Chitosan was modified by conjugating coupling with linolenic acid through the 1-ethyl-3-(3-dimethylami- nopropyyl) carbodiimide (EDC)-mediated reaction. The degree of substitution 1.8% ( i.e. 1.8 linolenic acid g... Chitosan was modified by conjugating coupling with linolenic acid through the 1-ethyl-3-(3-dimethylami- nopropyyl) carbodiimide (EDC)-mediated reaction. The degree of substitution 1.8% ( i.e. 1.8 linolenic acid group per 100 anhydroglucose units) was measured by ^1H NMR. The critical aggregation concentration (CAC) of the self-aggregate of hydrophobically modified chitosan was determined by measuring the fluorescence intensity of the pyrene as a fluorescent probe. The CAC value in phosphate-buffered saline (PBS) solution (pH 7.4) was 5 × 10^-2 mg mL^-1. The average particle size of selfaggregates of hydrophobically modified chitosan in PBS solution (pH7.4) was 210.8 nm with a unimodal size distribution ranging from 100 to 500 nm. Transmission electron microscopy (TEM) study showed that the formation of near spherical shape nanoparticles has enough structural integrity. The loading ability of hydrophibically modified chitosan (LA-chitosan) was investigated by using bovine serum albumin (BSA) as the model. The loading capacity of self-aggregated nanoparticles increases ( 19.85 % ± 0.04 % to 37.57 % ± 0.25 % ) with the concentration of BSA (0.1-0.5 mg mL^-1 ). 展开更多
关键词 CHITOSAN linolenic acid NANOPARTICLES self-aggregates BSA
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Effects of Ce^(3+) on improvement of spectral characteristics and function of chloroplasts damaged by linolenic acid in spinach 被引量:2
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作者 刘晓晴 迮玉官 +5 位作者 刘超 周敏 李娜 段艳梅 殷四涛 洪法水 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第2期288-293,共6页
Linolenic acid has great effects on the structure and function of chloroplast. We studied the effects of Ce3+ on the improvement of chloroplast spectral characteristics and oxygen evolution damaged by linolenic acid ... Linolenic acid has great effects on the structure and function of chloroplast. We studied the effects of Ce3+ on the improvement of chloroplast spectral characteristics and oxygen evolution damaged by linolenic acid in spinach. Results showed that Ce3+ could decrease the light absorption increased by linolenic acid and promote the distribution of excitation energy to PS II and alleviate the decrease of PS Ⅱ fluo- rescence yield caused by linolenic acid. The linolenic acid treatments in various concentrations reduced the oxygen-evolving rate of chloroplasts, but the rate was accelerated since adding Ce3+. 展开更多
关键词 Ce3+ linolenic acid CHLOROPLASTS spectral characteristic O2-evolving rare earths
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Effect of Altering Linoleic Acid and Linolenic Acid Dietary Ratios on the Performance and Tissue Fatty Acid Profiles of Prawn, Macrobrachium rosenbergii (de Man 1879) Post Larvae 被引量:11
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作者 A. M. A. S. Goda M. M. Habashy +5 位作者 M. A. Hanafy R. A. Mohamed H. A. Mabrouk T. M. El-Afifi S. A.Nada K. A. Mohamed 《Journal of Agricultural Science and Technology(B)》 2011年第7期1032-1044,共13页
A 90-day experiment was conducted to investigate the effects of different dietary linoleic acid (LA; 18:2n-6) and linolenic acid ratios (LNA; 18:3n-3) on growth induces, feed utilization and tissue fatty acid pr... A 90-day experiment was conducted to investigate the effects of different dietary linoleic acid (LA; 18:2n-6) and linolenic acid ratios (LNA; 18:3n-3) on growth induces, feed utilization and tissue fatty acid profile of freshwater prawn, Macrobrachium rosenbergii post-larvae (PL). The experiment was conducted in cubic indoor fiberglass tanks, each holding 700 L in triplicate. Post-larvae with an average weight of 20.8 ± 0.20 mg were stocked at 80 PL m2. Five experimental isocaloric (15.06 MJ kgl digestible energy), and isonitrogenous (30.45% digestible protein) diets were formulated by blending of soybean oil and linseed oil to containing five dietary LA/LNA ratios (7.80, 2.75, 1.28, 0.65 and 0.30). The highest survival values were recorded for prawn PL fed diet containing 0.65 LA/LAN ratios. Growth indices of PL significantly increased (P 〈 0.05) with decreased dietary LA/LAN ratios to 0.65. The same trend was observed for the highest (P ≤ 0.05) protein efficiency ratio, protein productive value, fat retention, energy retention and best feed conversion ratio. The total whole tissue polyunsaturated fatty acid composition of M. rosenbergii PL was dominated by LA followed by LAN. Post larvae fed the diets containing higher LA/LNA ratios showed a higher tissue LA/LNA ratio. The obtained findings revealed that fatty acid patterns ofM. rosenbergii PL were influenced by fatty acid profiles of diets. The diet containing 0.65 LA/LNA ratio is recommended to obtaining optimum growth performance and feed utilization for M. rosenbergii PL. 展开更多
关键词 Fatty acids linoleic linolenic Macrobrachium rosenbergii dietary ratio.
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MONOMER REACTIVITY RATIO AND THERMAL PERFORMANCE OFα-METHYL STYRENE AND GLYCIDYL METHACRYLATE COPOLYMERS 被引量:4
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作者 梁淑君 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第3期323-330,共8页
Synthesis and characterization of the copolymers (PAG) of α-methyl styrene (AMS) and glycidyl methacrylate (GMA) are presented. The copolymers of PAG were characterized by gel permeation chromatography (GPC),... Synthesis and characterization of the copolymers (PAG) of α-methyl styrene (AMS) and glycidyl methacrylate (GMA) are presented. The copolymers of PAG were characterized by gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (^1H-NMR) and thermogravimetery (TG). Based on the copolymer compositions determined by ^1H-NMR, the reactivity ratios of AMS and GMA were found to be 0.105 ± 0.012 and 0.883 ± 0.046 respectively by Kelen-Tudos method. TG revealed that thermal stability of the copolymers decreased with increasing the AMS content in the copolymers, which indicated that the degradation was mainly caused by the chain scission of AMS-containing structures. Under heating, the copolymers depolymerize at their weak bonds and form chain radicals, which could further initiate other chemical reactions. 展开更多
关键词 COPOLYMERIZATION α-methyl styrene Glycidyl methacrylate Reactivity ratios DEPOLYMERIZATION
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Alleviation effects of Ce^(3+) on inhibition of photochemical activity caused by linolenic acid in spinach chloroplast 被引量:1
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作者 刘晓晴 黄浩 +4 位作者 刘超 马玲兰 刘洁 殷四涛 洪法水 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第6期875-879,共5页
Linolenic acid has great effects on the structure and function of chloroplast. The function of Ce^3+ on the improvement of chloroplast photoreduction activity and oxygen evolution damaged by linolenic acid in spinach... Linolenic acid has great effects on the structure and function of chloroplast. The function of Ce^3+ on the improvement of chloroplast photoreduction activity and oxygen evolution damaged by linolenic acid in spinach by in vitro investigation was studied. Results showed that adding Ce^3+ to the linolenic acid treated chloroplast could greatly decrease the reduction linolenic acid exerted on the whole chain electron transport rate and the photoreduction activity of photosystem Ⅱ (PSII) and photosystem Ⅰ (PSI) as well as the oxygen evolution rate of chloroplast. It indicated that Ce^3+ had the ability to relieve the inhibition of the photochemical reaction of chloroplast caused by linolenic acid to some extent. 展开更多
关键词 Ce^3+ linolenic acid CHLOROPLAST photochemical action rare earths
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Characterization ofanovel deep-seamicrobial esterase EstC 10 and its use in the generation o f(R)-methyl 2-chloropropionate 被引量:5
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作者 GONG Yanhui MA Sanmei +4 位作者 WANG Yongfei XU Yongkai SUN Aijun ZHANG Yun HU Yunfeng 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第2期473-482,共10页
A novel esterase EstC10 from Bacillus sp. CX01 isolated from the deep sea of the Western Pacific Ocean and the functionalities of EstC 10 was characterized. At present, the reports about the kinetic resolution ofracem... A novel esterase EstC10 from Bacillus sp. CX01 isolated from the deep sea of the Western Pacific Ocean and the functionalities of EstC 10 was characterized. At present, the reports about the kinetic resolution ofracemic methyl 2-chloropropionate were quite rare. So we developed deep-sea microbial esterase EstC10 as a novel biocatalyst in the kinetic resolution of racemic methyl 2-chloropropionate and generate (R)-methyl 2-chloropropionate with high enantiomeric excess (〉99%) after the optimization of process parameters such as pH, temperature, organic co-solvents, surfactants, substrate concentration and reaction time. Notably, the optimal substrate concentration (80 mmol/L) of esterase EstC10 was higher than the kinetic resolution of another esterase, Estl2-7 (50 mmoFL). The novel microbial esterase EstC10 identified from the deep sea was a promising green biocatalyst in the generation of (R)-methyl 2-chloropropionate as well of many other valuable chiral chemicals in industry. 展开更多
关键词 BIOCATALYSIS deep-sea microorganisms novel esterase kinetic resolution (R)-methyl 2-chloropropionate
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Microwave-assisted synthesis of new N^4-[bi-(4-fluorophenyl)-methyl]-piperazine thiosemicarbazones under solvent-free conditions 被引量:4
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作者 Qing Han Li Zhi Gang Zhao 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第9期1035-1038,共4页
Six new N4-[bi-(4-fluorophenyl)-methyl]-piperazine thiosemicarbazones 3a-f have been prepared starting from [bi-(4-fluorophenyl)-methyl]-piperazine in solvent-free condition under microwave irradiation with excell... Six new N4-[bi-(4-fluorophenyl)-methyl]-piperazine thiosemicarbazones 3a-f have been prepared starting from [bi-(4-fluorophenyl)-methyl]-piperazine in solvent-free condition under microwave irradiation with excellent yields. Their structures have been determined by elemental analysis, IR, MS and 1H NMR data. 展开更多
关键词 bi-(4-Fluorophenyl)-methyl]-piperazine THIOSEMICARBAZONES Microwave irradiation SOLVENT-FREE Organic synthese
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Controlled Self-assembly of Two Coordination Polymers via subtly Varying Bis(2-methyl imidazole) Ligands:from 3-Connected(6,3) Net to 4-Connected sql Net 被引量:4
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作者 王桂霞 吴海霞 +1 位作者 李召好 赵邦屯 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第7期1074-1080,共7页
Two coordination polymers constructed from 3,4-thiophenedicarboxylic acid and bis(2-methyl imidazole) ligands, namely, {[Cd2(tdc)2(bip)2]·7H20}n (1) and [Cd(tdc)(bib)]n (2) (Hgtdc = 3,4-thiophenedi... Two coordination polymers constructed from 3,4-thiophenedicarboxylic acid and bis(2-methyl imidazole) ligands, namely, {[Cd2(tdc)2(bip)2]·7H20}n (1) and [Cd(tdc)(bib)]n (2) (Hgtdc = 3,4-thiophenedicarboxylic acid, bip = 1,3-bis-(imidazol-2-methyl)propane and bib = 1,4-bis(imidazol-2-methyl)butane), have been synthesized and structurally characterized by single-crystal X-ray diffraction. Structural analyses reveal that 1 exhibits a two-dimensional (2D) layered network with 3-connected (6,3) topology, which is further connected into a three- dimensional (3D) supramolecular structure by intermolecular hydrogen bonds. However, 2 features a 2D network which can be rationalized as a 4-connected sql net. The results indicate the subtle difference of auxiliary bis(imidazol-2-methyl) ligands may lead to diverse architectures. Moreover, they exhibit luminescence emission in the solid state at room temperature. 展开更多
关键词 3 4-thiophenedicarboxylic acid bis(imidazoi-2-methyl ligands crystal structure photoluminescent properties
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Urinary Concentrations of Hydroxyproline and 3-Methyl Histidine in Postpartum Cow 被引量:1
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作者 TIANWen-ru HEJian-bin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2001年第1期23-29,共7页
The urinary concentrations of hydroxyproline (HYPRO)and 3 -methyl histidine (3 - MEHIS) were de- termined in 16 Chinese-Holstein cows. The objectives of the experiment were to find out thhe relationship between collag... The urinary concentrations of hydroxyproline (HYPRO)and 3 -methyl histidine (3 - MEHIS) were de- termined in 16 Chinese-Holstein cows. The objectives of the experiment were to find out thhe relationship between collagen and myosin ddegradation and uterine involution in the postpartum cow. The results in the experiment showed that the mean concentrations of HYPRO and 3-MEHIS were 138.32±22.99 and 37.09 ±3.90 nmol·mL-1,respectively,for the cows during the days between 60-90 postpartum,and for the cows immediately after calving the concentrations of HYPRO and 3 -MEHIS reduced from 284.30 and 65.48 nmol ·mL-1 on the day one after calving to the normal level of 109.18 and 33.51 nmol·mL^-1 on the day 50 post- partum,respectively. There was a good correlation between the urinary concentrations of both HYPRO and 3 -MEHIS and the diameters of the involuting uterus (r = 0. 79). 展开更多
关键词 COW 3-methyl histidine HYDROXYPROLINE uterine involution
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Evaluation of anti-tubercular activity of linolenic acid and conjugatedlinoleic acid as effective inhibitors against Mycobacterium tuberculosis 被引量:4
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作者 Won Hyung Choi 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2016年第2期121-125,共5页
Objective: To evaluate a new pharmacological activity/effect of linolenic acid(α- and γ-form) and conjugated-linoleic acid(CLA) causing antibacterial activity against Mycobacterium tuberculosis(Mtb). Methods: The an... Objective: To evaluate a new pharmacological activity/effect of linolenic acid(α- and γ-form) and conjugated-linoleic acid(CLA) causing antibacterial activity against Mycobacterium tuberculosis(Mtb). Methods: The anti-Mtb activity/effect of linolenic acid and CLA were determined using different anti-Mtb indicator methods such as resazurin microtiter assay(REMA) and MGIT 960 system assay. The Mtb was incubated with various concentrations(12.5–200) μg/m L of the compounds and anti-Mtb first-line drugs for 5 d in the REMA, and for 3 wk in MGIT 960 system assay. Results: Linolenic acid and CLA obviously indicated their anti-Mtb activity/effect by strongly inhibiting the growth/proliferation of Mtb in a dosedependent manner in the REMA and the MGIT 960 system assay. Interestingly, linolenic acid and CLA consistently induced anti-Mtb activity/effect by effectively inhibiting the growth/proliferation of Mtb in MGIT 960 system for 21 d with a single-treatment, and their minimum inhibitory concentrations were measured as 200 μg/m L respectively. Conclusions: These results demonstrate that linolenic acid and CLA not only have effective anti-Mtb activity/properties, but also induce the selective-anti-Mtb effects by strongly inhibiting and blocking the growth/proliferation of Mtb through a new pharmacological activity/action. Therefore, this study provides novel perspectives for the effective use of them and the potential that can be used as potent anti-Mtb candidate drugs, as well as suggests the advantage of reducing the cost and/or time for developing a new/substantive drug by effectively repurposing the existing drugs or compounds as one of new strategies for the global challenge of tuberculosis. 展开更多
关键词 MGIT 960 system TUBERCULOSIS DRUG SUSCEPTIBILITY testing γ-linolenic acid
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Functional characterization of a novel microbial esterase identified from the Indian Ocean and its use in the stereoselective preparation of(R)-methyl mandelate 被引量:3
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作者 梁甲元 孙爱君 +4 位作者 张云 邓盾 王永飞 马三梅 胡云峰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第6期1269-1277,共9页
Genomic mining has identifi ed a novel microbial alkaline esterase from the Indian Ocean. This esterase was overexpressed in E. coli BL21(DE3) and further functionally characterized. Under optimal conditions(10 mmo... Genomic mining has identifi ed a novel microbial alkaline esterase from the Indian Ocean. This esterase was overexpressed in E. coli BL21(DE3) and further functionally characterized. Under optimal conditions(10 mmol/L substrate, p H 6.0, 2 h at 40 ℃), this esterase can hydrolyze racemic methyl mandelate to( R)-methyl mandelate with very high optical purity(e. e. 〉99%) and yield(nearly 90%). Interestingly, the stereoselectivity of this esterase is opposite to that of two previously reported lipases that can generate( S)-methyl mandelate through the hydrolysis of racemic methyl mandelate. No organic solvents or other additives were required to optimize the optical purity and production of the fi nal chiral product(R)-methyl mandelate, which can potentially simplify the production procedure of( R)-methyl mandelate catalyzed by esterase. 展开更多
关键词 alkaline esterase kinetic resolution (R)-methyl mandelate high optical purity opposite stereoselectivity
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Formulation ofα-linolenic acid microemulsion free of co-surfactant 被引量:2
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作者 Feng Liu Zheng Wu Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第1期105-108,共4页
A novel class ofα-linolenic acid-in-water microemulsion free of co-surfactant was investigated as potential food delivery systems.Rough demarcation within the transparent region was deduced from the results of conduc... A novel class ofα-linolenic acid-in-water microemulsion free of co-surfactant was investigated as potential food delivery systems.Rough demarcation within the transparent region was deduced from the results of conductivity and polarizing optical microscopy.The microemulsion mean hydrodynamic diameter and characterization were determined by dynamic light scattering and negative-staining TEM.The location of ALA molecules in the microemulsion formulations was determined by ~1H NMR spectroscopy. 展开更多
关键词 MICROEMULSION α-linolenic acid Particle diameter ~1H NMR
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The Preparation and Characterization of Conjugated Linolenic Acid
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作者 Cao Ying Yang Lin Chen Zhen-Yu 《合成化学》 CAS CSCD 2004年第z1期150-150,共1页
关键词 Conjugated linolenic Acid tung oil POMEGRANATE ISOMERIZATION
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Theoretical Study on the Reaction Mechanism of o-Aminophenol, Acetic Acid and Phosphorus Oxytrichloride One-pot to Form 2-Methyl Benzoxazole
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作者 ZHANG Fu-Lan 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第12期1869-1877,1843,共10页
The reaction mechanism of o-aminophenol, acetic acid and phosphorus oxytrichloride in one-pot to form 2-methyl benzoxazole was studied by density functional theory. The geometries of the reactants, transition states, ... The reaction mechanism of o-aminophenol, acetic acid and phosphorus oxytrichloride in one-pot to form 2-methyl benzoxazole was studied by density functional theory. The geometries of the reactants, transition states, intermediates and products were optimized at the GGA/PW91/DNP level. Vibration analysis was carried out to confirm the transition state structure. Two possible reaction pathways were investigated in this study. The result indicates that the reaction Re→TS1→IM1→TSA2→IMA2→TSA3→IMA3→TSA4→IMA4→TSA5→P2 is the main pathway, the activation energy of which is the lowest. Re→TS1→IM1 is the rate-limiting step, with the activation energy being 221.54 kJ·mol^(-1) and the reaction heat being 10.06 kJ·mol^(-1). The dominant product predicted theoretically is in agreement with the experiment results. 展开更多
关键词 O-AMINOPHENOL acetic acid phosphorus oxytrichloride 2-methyl benzoxazole density functional reaction mechanism
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XRD Pattern of Liquid Crystal Monomer Acrylate That Conjugated with Cholesterol and p-Hydroxyphenyl-2-Methyl Butanoic
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作者 Afrlzal Muhammad Hikam +1 位作者 Bambang Soegiyono Asep Riswoko 《Journal of Chemistry and Chemical Engineering》 2012年第12期1051-1055,共5页
It was successfully synthesized liquid crystal monomer acrylate that conjugated with two mesogens were cholesterol and p-hydroxyphenyl-2-methyl Butanoat which called MA (monomer cholesteryl acrylate) and monomer (S... It was successfully synthesized liquid crystal monomer acrylate that conjugated with two mesogens were cholesterol and p-hydroxyphenyl-2-methyl Butanoat which called MA (monomer cholesteryl acrylate) and monomer (S)-(+)-4-(2-Methyl butanoat-l-butyloxy) phenyl 4-[1-(propenoyloxy) butyloxy] benzoate (MB). Two monomers were characterized by DSC (differential scanning calorimetry), POM (polarization optical microscopy) and XRD (X-ray diffraction). Mesophase temperatures of MA and MB are 81.28 ~C and 54.36~C, respectively. Textures analysis by POM shows that MA was oily streak and MB was schlieren. XRD pattern shows the strongest three peaks of MA at room temperature which are (20, deg): 2.7153, 5.2992 and 18.8500. The Strongest three peaks of MB at room temperature are (20, deg): 9.1726, 9.7707 and 12.5389. XRD pattern of MA and MB at mesophase and above mesophase temperature that each peaks disappear. 展开更多
关键词 Liquid crystal cholesteryl acrylate p-hydroxyphenyl-2-methyl butanoat.
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Interaction of N-(2-Methyl Thio Phenyl)-2-Hydroxy-1-Naphthaldimine with Tin Dioxide Nanoparticles: A Spectroscopic Approach
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作者 Suvetha Rani Jayaprakash Ramakrishnan Veerabahu 《American Journal of Analytical Chemistry》 2012年第8期518-523,共6页
The interaction of N-(2-methyl thiophenyl)-2-hydroxy-1-naphthaldimine (NMTHN) with tin dioxide nanoparticles (SnO2 NPs) has been investigated by spectroscopic tools such as absorption and fluorescence spectroscopy. Ab... The interaction of N-(2-methyl thiophenyl)-2-hydroxy-1-naphthaldimine (NMTHN) with tin dioxide nanoparticles (SnO2 NPs) has been investigated by spectroscopic tools such as absorption and fluorescence spectroscopy. Absorption spectroscopy reveals the formation of ground state complex. Fluorescence spectroscopy has been used to study the signatures of fluorescence quenching. SnO2 NPs are found to quench the intrinsic fluorescence of NMTHN via static and dynamic quenching. The deviation from linearity in the Stern-Volmer plot has been observed. 展开更多
关键词 N-(2-methyl Thiophenyl)-2-Hydroxy 1-Naphthaldimine Tindioxide NANOPARTICLES Optical Absorption Fluorescence Quenching
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