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1.
橄榄苦苷酶水解产物具有良好的生物活性,为了促进纤维素酶水解橄榄苦苷,本研究通过天然低共熔溶剂(natural deep eutectic solvent, NADES)对纤维素酶稳定性的促进作用,形成NADES-纤维素酶溶剂系统促进橄榄苦苷的酶水解。以橄榄苦苷酶水解率为指标,考察温度、pH和DES种类及浓度对纤维素酶水解橄榄苦苷的影响。结果表明:在50℃,pH=5时水解3 h,以10%(V/V)DES-5(甜菜碱∶1,4-丁二醇=1∶2,n/n)为溶剂系统的橄榄苦苷酶水解率是缓冲液的1.7倍;证明以氯化胆碱或甜菜碱为氢键受体(hydrogen bond acceptor, HBA),多元醇为氢键供体(hydrogen bond donor, HBD)的NADES对增强纤维素酶稳定性、促进橄榄苦苷酶水解具有良好的效果,为高效制备橄榄苦苷酶水解产物提供了科学依据。  相似文献   

2.
本文对素馨花中提取纯化所得橄榄苦苷在大鼠体内的药代动力学过程进行研究。将雄性Wistar大鼠随机分为橄榄苦苷100、200、400 mg/kg剂量组,灌胃(i.g.)给药后不同时间采血,离心,血浆经甲醇-乙腈沉淀蛋白后,HPLC测定不同时间点大鼠血浆中橄榄苦苷的含量。各给药组平均血药浓度-时间数据应用3P97软件进行药代动力学参数分析,组间药动学参数用SPSS 17.0进行统计分析。结果表明,橄榄苦苷在大鼠体内的药代动力学过程符合二室模型,低、中、高剂量组的t1/2、CL/F、AUC差异具有显著的统计学意义,其中t1/2、CL/F随给药剂量的增大而增大;AUC随剂量的增大,呈先减小后增大的趋势,橄榄苦苷在大鼠体内的药代动力学呈非线性过程。  相似文献   

3.
马鞭草的化学成分研究(Ⅱ)   总被引:2,自引:0,他引:2  
从马鞭草的乙醇提取物中分离得到7个化合物,经理化特征及波谱数据分析确定其结构分别为龙胆苦苷(1),槲皮苷(2),山柰酚(3),毛蕊花糖苷(4),桃叶珊瑚苷(5),β-谷甾醇(6)和熊果酸(7)。其中化合物1~3为首次从该植物中分离得到。  相似文献   

4.
苦槛蓝叶中的黄酮类化合物   总被引:2,自引:0,他引:2  
为了解苦槛蓝(Myoporum bontioides A.Gray)的化学成分,采用色谱分离技术从苦槛蓝叶片中分离得到11个黄酮类化合物。通过波谱分析,他们的结构分别鉴定为:桔皮素(1)、甜橙素(2)、5,4′-二羟基-6,7,8,3′-四甲氧基黄酮(3)、4′,5,7,8-四甲氧基黄酮(4)、去甲基川陈皮素(5)、5-羟基-6,7,3′,4′-四甲氧基黄酮(6)、3′,4′,5,6,7,8-六甲氧基黄酮(7)、二氢山柰酚(8)、木犀草素(9)、3′,4′,5,7-四羟基-3-甲氧基黄酮(10)和芹黄素(11)。除化合物9之外,其他化合物均为首次从苦槛蓝叶片中分离得到。孢子萌发法测定结果表明,化合物1,2,8和9对香蕉炭疽菌(Colletotrichum musae)具有较好的抑菌活性。这为苦槛蓝叶片中有效成分的利用提供了理论依据。  相似文献   

5.
目前橄榄苦苷的分离、纯化研究主要集中在大孔吸附树脂,但鲜有阴离子树脂分离、纯化橄榄苦苷的报道。为了研究阴离子树脂(LX-68M)吸附、分离过程及性能,采用吸附动力学及等温吸附模型来研究阴离子树脂静态吸附、解吸橄榄苦苷的行为。结果表明阴离子树脂对橄榄苦苷的吸附符合准二级动力学模型(R2=0.993 4),Freundlich等温吸附模型(R2=0.964 2)。进一步通过动态实验优化阴离子树脂纯化橄榄苦苷工艺,最佳操作工艺为:上样浓度为0.25 g/mL,解吸液为45%乙醇,吸附、解吸速率均为2.0 BV/h。该条件下橄榄苦苷的吸附率、解吸率分别为86.86%、87.08%,纯度为52.33%。此外,阴离子树脂重复使用4次后吸附率为54.9%,经再生处理后,吸附率恢复到93.51%,表明其具有一定的工业化前景。阴离子树脂稳定性好、分离条件温和,适合用于橄榄苦苷及其他相似天然产物的分离纯化。  相似文献   

6.
根据Box-Benhnken中心组合实验设计的原理,在单因素实验的基础上,选取了对橄榄苦苷提取率影响较大的4个因素(温度、超声功率、提取时间和料液比),采用4因素3水平的响应曲面分析法,建立了油橄榄叶中橄榄苦苷提取的二次多项式数学模型,优化橄榄苦苷的超声提取最佳工艺条件,在温度51℃,超声功率71W,提取时间32 min,料液比1:30条件下,橄榄苦苷提取率达到7.18%.与常规溶剂法相比,超声波提取是一种生产成本低、提取效率高、周期短的方法,具有良好的开发前景.  相似文献   

7.
为研究苦槛蓝(Myoporum bontioides A.Gray)的化学成分,采用多种柱色谱技术从苦槛蓝叶中分离得到13个化合物,它们的结构分别鉴定为:野黑樱苷(1)、类叶升麻苷(2)、5,7-二羟基二氢黄酮(3)、3-O-β谷甾醇苷(4)、(3R)-oct-1-en-3-ol-O-β-D-glucopyranosyl-(1″→2′)-O-β-D-glucopyranoside(5)、7-甲氧基香橙素(6)、异樱花素(7)、匙叶桉油烯醇(8)、愈创木醇(9)、(1S,2R,5S,6R)-2,6-bis(5-methoxy-3,4-methylenedioxyphenyl)-3,7-dioxabicyclo[3.3.0]octane(10)、(1R,2S,5R,6S)-2-(4-hydroxy-3-methoxyphenyl)-6-(3,4-methylenedioxyphenyl)-3,7-dioxabicyclo[3.3.0]octane(11)、去甲基川陈皮素(12)和3′,4′,5,6,7,8-六甲氧基黄酮(13),其中化合物4、5、7~11为首次从苦槛蓝植物中分离得到。刃天青显色法测试部分化合物对大肠杆菌与金黄色葡萄球菌的抑制活性,结果表明,5,7-二羟基二氢黄酮(3)对大肠杆菌与金黄色葡萄球菌有一定的抑制作用,其MIC值为62.50μg mL–1。  相似文献   

8.
抱茎苦荬菜水溶性成分的分离与结构鉴定   总被引:3,自引:0,他引:3  
从抱茎苦荬菜的水溶性成分分离得到5个化合物,根据理化性质和光谱数据分别鉴定为木犀草素-7-O-β-D-葡萄糖醛酸苷(1),木犀草素-7-O-β-D-葡萄糖1→2葡萄糖苷(2),芹菜素-7-O-β-D-葡萄糖醛酸苷(3),菊苣酸(4),(-)3,4-二羟基咖啡酰基酒石酸(5)。化合物3~5为首次从该植物中分离得到。  相似文献   

9.
苦玄参的化学成分研究   总被引:1,自引:1,他引:0  
对广西传统的抗菌消炎药用植物苦玄参进行了化学成分研究,采用柱色谱进行分离纯化,运用波谱法进行了结构解析,共鉴定得到7个化合物。它们分别为:芹菜素(1)、芹菜素-7-O-β-D-葡萄糖酸(2)、芹菜素-7-O-α-L-吡喃鼠李糖基(1→2)-β-D-吡喃葡萄糖酸(3)、迷迭香酸(4)、苦玄参苷Ⅳ(5)、苦玄参苷Ⅹ(6)、阿克替苷(7)。其中化合物2、3、4为首次从该植物中分离得到。  相似文献   

10.
油橄榄叶中橄榄苦苷的分离纯化   总被引:1,自引:0,他引:1  
考察了6种不同大孔树脂对橄榄苦苷的吸附,筛选出吸附选择性好的D101大孔吸附树脂为实验材料.得到的D101大孔树脂的最佳吸附条件:试样上样质量浓度41.06[J].,流速5 mL/min,50%乙醇溶液洗脱,洗脱液用量260mL,树脂可以反复使用.经大孔树脂富集后,橄榄苦苷的纯度可达55%以上,再经葡聚糖凝胶精纯化后,可达76%以上.  相似文献   

11.
Phytosulfokine-alpha (PSK-alpha), a sulfated growth factor (H-Tyr(SO3H)-Ile-Tyr(SO3H)-Thr-Gln-OH) universally found in both monocotyledons and dicotyledons, strongly promotes proliferation of plant cells in culture. In our studies on structure/activity relationship in PSK-alpha the synthesis of a series of analogues was performed: [H-D-Tyr(SO3H)1]- (9), [H-Phe(4-SO3H)1]- (10), [H-D-Phe(4-SO3H)1]- (11), [H-Phg(4-SO3H)1]- (12), [H-D-Phg(4-SO3H)1]- (13), H-Phe(4-NHSO2CH3)1]- (14), [H-D-Phe(4-NHSO2CH3)1]- (15), [H-Phe(4-NO2)1]- (16), [H-D-Phe(4-NO2)1]- (17), [H-Phg(4-NO2)1]- (18), [H-D-Phg(4-NO2)1]- (19), [H-Hph(4-NO2)1]- (20), [H-Phg(4-OSO3H)1]- (21), [Phe(4-NO2)3]- (22), [Phg(4-NO2)3]- (23), [Hph(4-NO2)3]- (24), [H-Phe(4-SO3H)1, Phe(4-SO3H)3]- (25) [H-Phe(4-NO2)1, Phe(4-NO2)3]- (26), [H-Phg(4-NO2)1, Phg(4-NO2)3]- (27), [H-Hph(4-NO2)1, Hph(4-NO2)3]- (28) and [Val3]- PSK-alpha (29). For modification of the PSK-alpha peptide chain the novel amino acids and their derivatives were synthesized, such as: H-L-Phg(4-SO3H)-OH (1), H-D-Phg(4-SO3H)-OH (2), Fmoc-Phg(4-SO3H)-OH (3), Fmoc-D-Phg(4-SO3H)-OH (4), Boc-Phg(4-NHSO2CH3)-OH (5), Boc-D-Phg(4-NHSO2CH3)-OH (6) Boc-Phe(4-NHSO2CH3)-OH (7), and Boc-D-Phe(4-NHSO2CH3)-OH (8). Peptides were synthesized by a solid phase method according to the Fmoc procedure on a Wang-resin. Free peptides were released from the resin by 95% TFA in the presence of EDT. All peptides were tested by competitive binding assay to the carrot membrane using 3H-labelled PSK according to the Matsubayashi et al. test.  相似文献   

12.
从长形肉豆蔻Myristica argentea乙醇提取物乙酸乙酯部分分离得到12个化合物,经理化和波谱分析分别鉴定为黄樟醚(1)、甲基丁香酚(2)、异甲基丁香酚(3)、3′-羟基异黄樟醚(4)、7-羟基-3′,4′-亚甲二氧基黄烷(5)、1,4-苯二甲酸二甲酯(6)、内消旋-二氢愈创木脂酸(7)、赤式-1-(4-羟基-3-甲氧基苯基)-4-(3,4-亚甲二氧基苯基)-2,3-二甲基丁烷(8)、赤式-1-(4-羟基-3-甲氧基苯基)-2-(2-甲氧基-4-(1(E)-丙烯基)苯氧基)-丙烷-1-醇(9)、nectandrin B(10)、β-谷甾醇(11)和胡萝卜苷(12)。化合物4~6和8~12为首次自该植物中分离得到,化合物4~6为首次从该属植物中分离得到。  相似文献   

13.
广东土牛膝为菊科泽兰属植物华泽兰(Eupatorium chinense)的干燥根。从其甲醇提取物中共分离得到11个化合物,其中eupatorinA(1)为一新化合物,经波谱学方法鉴定为(threo)-3-O-acetyl-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxy-1-(E)-propenyl)-2,6-dimethoxyphenoxy]propyl-β-D-glucopy-ranoside。已知化合物分别鉴定为(threo)-3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxy-1-(E)-propenyl)-2,6-dimethoxyphenox-y]-propyl-β-D-glucopyranoside(2),ardisiacrispinA(3),ardisiac-rispinB(4),euparone(5),3-(2,3-dihydroxy-isopen-tyl)-4-hydroxyacetophenone(6),12,13-di-hydroxy-euparin(7),gymnastone(8),N-(2′-hydroxy-tetracosanosyl)-2-amino-1,3,4-trihydroxy-octa-dec-8-(E)-ene(9),stigmasterol(10)和stigmasterol-3-O-β-D-glucopyranoside(11)。化合物2-4为首次从菊科植物,5-8为首次从泽兰属植物中分离得到。  相似文献   

14.
Nine compounds, 3-hydroxy-4,5-dimethoxyphenyl-beta-D-glucopyranoside (1), beta-D-fructfuranosyl-alpha-D-(6-vanilloyl)-glucopyranoside (2), beta-D-fructfuranosyl-alpha-D-(6-syringyl)-glucopyranoside (3), 3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxy-1-(E)-propenyl)-2-methoxyphenoxy]propyl-beta-D-glucopyranoside (4), 3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxy-1-(E)-propenyl)-2,6-dimethoxyphenoxy] propyl-beta-D-glucopyranoside (5), dehydrodiconiferyl alcohol-9'-beta-D-glucopyranoside (6), 4-[ethane-2-[3-(4-hydroxy-3-methoxyphenyl)-2-propen]oxy]-2,6-dimethoxyphenyl-beta-D-glucopyranoside (7), 4-[ethane-2-[3-(4-hydroxy-3-methoxyphenyl)-2-propen]oxy]-2-methoxyphenyl-beta-D-glucopyranoside (8), and 3-hydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl)-2-[4-(3-hydroxy-1-(E)-propenyl)-2,6-dimethoxyphenoxy]propyl-beta-D-glucopyranoside (9), were isolated from Kokuto non-centrifuged cane sugar. Their structures were elucidated by spectroscopic evidence, mainly based on the NMR technique. Among them, seven new glycosides were identified. The 2-deoxyribose oxidation method was used to measure their antioxidative activity. All of these compounds showed antioxidative activities.  相似文献   

15.
Seven glutathione-S-transferase (GST) isozymes were purified from liver cytosol of intact male Wistar rats: 1-1(A), 1-1(B), 1-2, 2-2, 3-3, 3-4, 4-4. Treatment of rats with butylated hydroxytoluene (BHT) led to the induction of isozymes GST 1-1(A), 1-1(B) (2-fold), 3-3 (3.5-fold) as well as to the appearance of two new isozymes--1-3 and 4-4(A). Phenobarbital (PB) induced isozymes GST 1-1(A), 1-1(B) (2-fold) and 3-3 (1.5-fold). BHT and PB caused an increase in the specific activity of isozymes 1-1(A), 1-1(B), 3-3, 3-4 towards 1-chloro-2.4-dinitrobenzene and 1.2-dichloro-4-nitrobenzene. 3-Methylcholanthrene (MC) induced isozymes 1-2 (1.5-fold), 2-2 (2-fold) and 4-4 (3-fold). A conclusion was drawn that BHT and PB induced the GST subunits 1 and 3, whereas MC--subunits 2 and 4.  相似文献   

16.
One new compound, namely eupatorin A (1), was isolated from the methanolic extract of Guangdong Tu Niu Xi, the dried roots of Eupatorium chinense (Compositae). Its structure was determined to be (threo) 3 O acetyl 1 (4 hydroxy 3 methoxyphenyl) 2 \[4 (3 hydroxy 1 (E) propenyl) 2, 6 dimethoxyphenoxy\]propyl β D gluco pyranoside on the basis of detailed spectroscopic analysis. In addition, ten known compounds, including (threo) 3 hydroxy 1 (4 hydroxy 3 methoxyphenyl) 2 \[4 (3 hydroxy 1 (E) propenyl) 2, 6 dimethoxyphenoxy\]propyl β D glucopyranoside (2), ardisiacrispin A (3), ardisiacrispin B (4), euparone (5), 3 (2, 3 dihydroxy isopentyl) 4 hydroxy acetophenone (6), 12,13 dihydroxy euparin (7), gymnastone (8), N (2′ hydroxy tetracosanosyl) 2 amino 1, 3, 4 trihydroxy octadec 8 (E) ene (9), stigmasterol (10) and stigmasterol 3 O β D glucopyranoside (11) were also obtained. This was the first time that compounds 2-4 were reported from Compositae family, while 5-8 were isolated from the genus Eupatorium.  相似文献   

17.
Li JZ  Liu HY  Lin YJ  Hao XJ  Ni W  Chen CX 《Steroids》2008,73(6):594-600
Six new C21 steroidal glycosides, named curassavosides A–F (3–8), were obtained from the aerial parts of Asclepias curassavica (Asclepiadaceae), along with two known oxypregnanes, 12-O-benzoyldeacylmetaplexigenin (1) and 12-O-benzoylsarcostin (2). By spectroscopic methods, the structures of the six new compounds were determined as 12-O-benzoyldeacylmetaplexigenin 3-O-β-d-oleandropyranosyl-(1 → 4)-β-d-digitoxopyranoside (3), 12-O-benzoylsarcostin 3-O-β-d-oleandropyranosyl-(1 → 4)-β-d-digitoxopyranoside (4), sarcostin 3-O-β-d-oleandropyranosyl-(1 → 4)-β-d-canaropyranosyl-(1 → 4)-β-d-oleandropyranosyl-(1 → 4)-β-d-digitoxopyranoside (5), sarcostin 3-O-β-d-oleandropyranosyl-(1 → 4)-β-d-canaropyranosyl-(1 → 4)-β-d-canaropyranosyl-(1 → 4)-β-d-digitoxopyranoside (6), 12-O-benzoyldeacylmetaplexigenin 3-O-β-d-glucopyranosyl-(1 → 4)-β-d-oleandropyranosyl-(1 → 4)-β-d-canaropyranosyl-(1 → 4)-β-d-oleandropyranosyl-(1 → 4)-β-d-digitoxopyranoside (7), and 12-O-benzoylsarcostin 3-O-β-d-glucopyranosyl-(1 → 4)-β-d-oleandropyranosyl-(1 → 4)-β-d-canaropyranosyl-(1 → 4)-β-d-oleandropyranosyl-(1 → 4)-β-d-digitoxopyranoside (8), respectively. All compounds (1–8) were tested for in vitro cytotoxicity; only compound 3 showed weak inhibitory activity against Raji and AGZY cell lines.  相似文献   

18.
广东土牛膝为菊科泽兰属植物华泽兰(Eupatorium chinense)的干燥根。从其甲醇提取物中共分离得到11个化合物,其中eupatorinA(1)为一新化合物,经波谱学方法鉴定为(threo)-3-O-acetyl-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxy-1-(E)-propenyl)-2,6-dimethoxyphenoxy]propyl-β-D-glucopy-ranoside。已知化合物分别鉴定为(threo)-3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxy-1-(E)-propenyl)-2,6-dimethoxyphenox-y]-propyl-β-D-glucopyranoside(2),ardisiacrispinA(3),ardisiac-rispinB(4),euparone(5),3-(2,3-dihydroxy-isopen-tyl)-4-hydroxyacetophenone(6),12,13-di-hydroxy-euparin(7),gymnastone(8),N-(2′-hydroxy-tetracosanosyl)-2-amino-1,3,4-trihydroxy-octa-dec-8-(E)-ene(9),stigmasterol(10)和stigmasterol-3-O-β-D-glucopyranoside(11)。化合物2-4为首次从菊科植物,5-8为首次从泽兰属植物中分离得到。  相似文献   

19.
We have synthesized several ganglio-oligosaccharide structures using glycosyltransferases from Campylobacter jejuni. The enzymes, alpha-(2-->3/8)-sialyltransferase (Cst-II), beta-(1-->4)-N-acetylgalactosaminyltransferase (CgtA), and beta-(1-->3)-galactosyltransferase (CgtB), were produced in large-scale fermentation from Escherichia coli and further characterized based on their acceptor specificities. 2-Azidoethyl-glycosides corresponding to the oligosaccharides of GD3 (alpha-D-Neup5Ac-(2-->8)-alpha-D-Neup5Ac-(2-->3)-beta-D-Galp-(1-->4)-beta-D-Glcp-), GT3 (alpha-D-Neup5Ac-(2-->8)-alpha-D-Neup5Ac-(2-->8)-alpha-D-Neup5Ac-(2-->3)-beta-D-Galp-(1-->4)-beta-D-Glcp-), GM2 (beta-D-GalpNAc-(1-->4)-[alpha-D-Neup5Ac-(2-->3)]-beta-D-Galp-(1-->4)-beta-D-Glcp-), GD2 (beta-D-GalpNAc-(1-->4)-[alpha-D-Neup5Ac-(2-->8)-alpha-D-Neup5Ac-(2-->3)]-beta-D-Galp-(1-->4)-beta-D-Glcp-), GT2 (beta-D-GalpNAc-(1-->4)-[alpha-D-Neup5Ac-(2-->8)-alpha-D-Neup5Ac-(2-->8)-alpha-D-Neup5Ac-(2-->3)]-beta-D-Galp-(1-->4)-beta-D-Glcp-), and GM1 (beta-D-Galp-(1-->3)-beta-D-GalpNAc-(1-->4)-[alpha-D-Neup5Ac-(2-->3)]-beta-D-Galp-(1-->4)-beta-D-Glcp-) were synthesized in high yields (gram-scale). In addition, a mammalian alpha-(2-->3)-sialyltransferase (ST3Gal I) was used to sialylate GM1 and generate GD1a (alpha-D-Neup5Ac-(2-->3)-beta-D-Galp-(1-->3)-beta-D-GalpNAc-(1-->4)-[alpha-D-Neup5Ac-(2-->3)]-beta-D-Galp-(1-->4)-beta-D-Glcp-) oligosaccharide. We also cloned and expressed a rat UDP-N-acetylglucosamine-4'epimerase (GalNAcE) in E. coli AD202 cells for cost saving in situ conversion of less expensive UDP-GlcNAc to UDP-GalNAc.  相似文献   

20.
1. Four ribonucleases were isolated from culture media of Ustilago sphaerogena. They were designated ribonucleases U(1), U(2), U(3) and U(4). 2. They were purified about 1600-, 3700-, 1100- and 16-fold respectively. 3. It was shown by gel filtration that ribonucleases U(1), U(2) and U(3) have molecular weights about 10000 like ribonuclease T(1), and that ribonuclease U(4) is much larger. 4. Ribonucleases U(1), U(2) and U(3) are thermostable, but ribonuclease U(4) is not. 5. The pH optimum of ribonucleases U(1) and U(4) is pH8.0-8.5, and that of ribonucleases U(2) and U(3) is pH4.5.  相似文献   

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