蚕沙粗品叶绿素酸降解产物的分离与鉴定

从蚕沙粗品叶绿素酸降解产物中分离制得在肿瘤中有选择性潴留作用,光动力学活性强于癌光啉的脱镁叶绿甲酯一酸 a 类组分混合物。经 HPLC 制备分离,~1H-NMR 和 MS 证明,它们为脱镁叶绿甲酯一酸 a(58%),脱镁叶绿甲酯一酸 a′(11%)和焦脱镁叶绿酸 a(31%)三种成分。     

蚕沙叶绿素提取及合成脱镁叶绿酸工艺改进研究

目的探讨不同提取工艺对蚕沙中提取叶绿素及制取叶绿素衍生物脱镁叶绿酸的影响,以提高蚕沙叶绿素及叶绿素衍生物的制备量。方法单因素实验设计,以蚕沙软化时间(含水量)、不同提取溶剂为考察条件,优化蚕沙叶绿素提取工艺,并探讨浓盐酸脱镁时间对叶绿素合成脱镁叶绿酸制备率的影响。结果蚕沙软化时间2 h(含水量26%)、丙酮∶乙醇体积比1∶1做溶剂为提取叶绿素的最佳条件,提取率提高到1.43%。以蚕沙叶绿素粗品合成叶绿素衍生物脱镁叶绿酸,浓盐酸脱镁搅拌反应72 h制备率达670 mg.g 1。结论通过改良工艺,提高了蚕沙叶绿素及其衍生物脱镁叶绿酸的提取制备率。     

脱镁叶绿酸的制备及其光敏抗菌活性

以初步纯化的叶绿素为原料,利用叶绿素酶水解、选择性酸降解两种方法制备脱镁叶绿酸。高效液相色谱分析显示两种方法得到的产物图谱相似,酸降解产物中脱镁叶绿酸A的含量较高。抗菌实验表明脱镁叶绿酸对革兰阳性菌具有光敏抑菌效果,对革兰阴性菌和酵母无明显作用。     

脱镁叶绿酸钙的制备

目的：制备脱镁叶绿酸钙。方法：以蚕沙提取叶绿素，由叶绿素制备脱镁叶绿酸，与氯化钙反应后制得脱镁叶绿酸钙。结果：所制得的脱镁叶绿酸钙为墨绿色固体，不溶于水，也不溶于95％乙醇。结论： 由红外光谱图分析，两个脱镁叶绿酸基与Ca^2 结合成脱镁叶绿酸钙，分子中还存在两个单体羧基，仅有一个钙原子。     

从蚕砂中制备脱镁叶绿酸的工艺研究

目的 :优化以蚕砂为原料制备脱镁叶绿酸工艺条件 ,提高产出率。方法 :以叶绿素提取率为指标 ,对脱镁叶绿酸制备的乙醇法和丙酮法工艺进行比较 ,用正交试验法对丙酮法的工艺条件进行优化。结果 :脱镁叶绿酸的最佳制备条件为蚕砂粉碎度60目 ,加1/10倍药材量的水软化5h以上 ,加3倍药材量的溶媒 ,提取温度70℃ ,回流时间60min ,提取次数2次 ,酸化时 pH调至2 5。结论 :软化水用量、丙酮量对叶绿素提取率影响较大 ,经优化后可提高丙酮法制备脱镁叶绿酸的产出率4 6倍     

亚硒酸锰（Ⅱ）—叶绿酸钠的制备及其对小鼠的急性毒性和小鼠肝癌H …

目的:制备亚硒酸锰(Ⅲ)-叶绿酸钠,并测定其对小鼠的急性毒性及对小鼠肝癌H22的抑制情况.方法:以蚕沙提取叶绿素,由叶绿素制备脱镁叶绿酸,与锰络合后制得锰(Ⅲ)叶绿酸,再以亚硒酸化合制得亚硒酸锰(Ⅲ)-叶绿酸钠;测定亚硒酸锰(Ⅲ)-叶绿酸钠的急性毒性及对小鼠肝癌H22的抑制情况.结果:作者首次合成了亚硒酸锰(Ⅲ)-叶绿酸钠.测得其LD50=1175 mg.kg-1(95%的可信区间为851～1621 mg.kg-1;其对小鼠肝癌H22的抑癌率为45～47%(灌胃剂量为500 mg.kg-1).结论:亚硒酸锰(Ⅲ)-叶绿酸钠常温下性质稳定,毒性小,对小鼠肝癌H22有明显的抑制作用,可进一步做临床试验.     

亚硒酸锰(Ⅲ)-叶绿酸钠的制备及其对小鼠的急性毒性和小鼠肝癌H22的初步试验

目的:制备亚硒酸锰(Ⅲ)-叶绿酸钠,并测定其对小鼠的急性毒性及对小鼠肝癌H22的抑制情况.方法:以蚕沙提取叶绿素,由叶绿素制备脱镁叶绿酸,与锰络合后制得锰(Ⅲ)叶绿酸,再以亚硒酸化合制得亚硒酸锰(Ⅲ)-叶绿酸钠;测定亚硒酸锰(Ⅲ)-叶绿酸钠的急性毒性及对小鼠肝癌H22的抑制情况.结果:作者首次合成了亚硒酸锰(Ⅲ)-叶绿酸钠.测得其LD50=1175 mg.kg-1(95%的可信区间为851～1621 mg.kg-1;其对小鼠肝癌H22的抑癌率为45～47%(灌胃剂量为500 mg.kg-1).结论:亚硒酸锰(Ⅲ)-叶绿酸钠常温下性质稳定,毒性小,对小鼠肝癌H22有明显的抑制作用,可进一步做临床试验.     

叶绿素降解产物金属络合物的合成及其对60Co辐射小鼠的放射保护作用

通过蚕沙叶绿素的降解反应,研究了焦脱镁叶绿酸a、二氢卟吩e₆单甲酯及紫红素18等二氢卟吩衍生物的制备方法,首次设计合成了蚕沙叶绿素降解产物的钴、铜、锌金属络合物。在确认结构的基础上观察了它们对60Co辐射小鼠的放射治疗作用,结果发现二氢卟吩e₆单甲酯铜络合物(7)能显著延长实验小鼠的存活时间,增加21d后小鼠存活数量。     

脱镁叶绿一酸a荧光特性研究

目的:研究中药蚕砂中脱镁叶绿一酸a的荧光性质。方法:采用丙酮提取,Al2O3柱层析和乙醚萃取自蚕砂中分离脱镁叶绿一酸a,采用荧光扫描确定其激发波长和发射波长,考察pH值、温度及光照时间对其荧光强度的影响。结果:脱镁叶绿一酸a的激发波长和发射波长分别为665和675 nm。pH碱性、提高温度可降低其荧光强度,光照则可提高其荧光强度。结论:脱镁叶绿一酸a在中性、酸性和低温条件下稳定,光照可加强其荧光效应。     

二氢卟吩e6衍生物的简便制备

蚕沙叶绿素粗提物经酸降解得到脱镁叶绿酸a粗品，不经分离，直接与亲核试剂如甲醇、乙胺发生开环反应，一步得到二氢卟吩e6衍生物。     

蚕沙叶绿素的降解及二氢卟吩P6酰胺衍生物的合成

以蚕沙粗品叶绿素为原料,经降解、氧化反应制得紫红素－１８（３）,并以３为关键中间体合成了１０个二氢卟吩Ｐ６酰胺衍生物,其中９个为首次报道。     

铜紫红素-18的合成及其保肝抗溃疡活性的初步研究

以蚕沙糊状叶绿素为原料，经脱镁、扩环制得紫红素－18，再与铜离子络合得到铜紫红素－18，收率32．7％，并以叶绿素铜钠为阳性对照，对其保肝及抗胃溃疡活性进行了初步研究。结果表明，给予本品后与空白对照相比，小鼠TAA急性肝损伤模型的SGPT活性和大鼠应激性胃溃疡模型溃疡指数显著降低。     

叶绿素a降解产物紫红素—18的光动力效应

对叶绿素a降解产物紫红素－18（1）在非细胞体系中的光敏化力和对小鼠肉瘤－180的光动力治疗作用进行了研究。结果表明,1在D2O中对NADPH的光氧化作用的敏化效应明显高于参比药物血卟啉衍生物（HpD);其4mg/kg时肿瘤抑制率可达95．1％,疗效较HpD显著（P＜0．01）。     

Determination of chlorophylls and their derivatives in Gynostemma pentaphyllum Makino by liquid chromatography-mass spectrometry

The objectives of this study were to develop a high performance liquid chromatography-mass spectrometry (HPLC-MS) method for determination of chlorophylls and their derivatives in Gynostemma pentaphyllum Makino, a traditional Chinese herb possessing vital biological activities. Chlorophylls were extracted with a quaternary solvent system of hexane-acetone-ethanol-toluene (10:7:6:7, v/v/v/v), followed by separation of a total of 15 chlorophylls and their derivatives within 32min using a gradient mobile phase of acetone, acetonitrile and methanol and a HyPURITY C18 column, with detection at 660nm and flow rate at 1mL/min. Identification was carried out on the basis of retention behavior, absorption spectra and mass spectra using atmospheric pressure chemical ionization (APCI) in positive ion mode for detection. Of the 15 analytes, chlorophyll a, chlorophyll b, pheophytin a and pheophytin b were quantified by using standard calibration curves, with the other 11 being quantified with an internal standard Fast Green FCF. Chlorophyll extracts in G. pentaphyllum were found to contain pheophytin a (2508.3mug/g), pheophytin a' (111.2mug/g), chlorophyll a (113.8mug/g), chlorophyll a' (11.0mug/g), hydroxypheophytin a (88.6mug/g), hydroxypheophytin a' (66.5mug/g), pyropheophytin a (76.0mug/g), hydroxychlorophyll a (23.8mug/g), pheophytin b (319.6mug/g), pheophytin b' (13.2mug/g), chlorophyll b (287.9mug/g), chlorophyll b' (11.1mug/g), hydroxychlorophyll b (15.0mug/g), hydroxypheophytin b (11.2mug/g) and hydroxypheophytin b' (8.5mug/g).     

叶绿素降解产物金属络合物的合成及其对~(60)Co辐射小鼠的放射保护作用

通过蚕沙叶绿素的降解反应，研究了焦脱镁叶绿酸ａ、二氢卟吩ｅ６单甲酯及紫红素１８等二氢卟吩衍生物的制备方法，首次设计合成了蚕沙叶绿素降解产物的钴、铜、锌金属络合物。在确认结构的基础上观察了它们对６０Ｃｏ辐射小鼠的放射治疗作用，结果发现二氢卟吩ｅ６单甲酯铜络合物（７）能显著延长实验小鼠的存活时间，增加２１ｄ后小鼠存活数量。     

Die Bornträger-Reaktion mit unsymmetr. substituiert. Hydroxyanthrachinonen

The Bornträger-Reaction with unsymmetrical substituted Hydroxyanthraquinones The behaviour of alizarin, quinizarin, purpurin and quinalizarin in the Bornträger-reaction has been examined. Alizarin proved to be very stable, quinizarin and quinalizarin were decomposed quickly, purpurin very quickly.     

荷移分光光度法测定脑脉康片中烟酸占替诺的含量

目的:测定脑脉康片中烟酸占替诺的含量。方法:通过烟酸占替诺与红紫素在乙醇与水混合溶液中发生荷移反应生成络合物,采用分光光度法测定其含量,检测波长为538nm;同时将测定结果与《中国药典》高效液相色谱法测定结果比较。结果:烟酸占替诺检测浓度范围为20～140mg·L-(1r=0.9989),表观摩尔吸光系数为2.46×103L·mol-1·cm-1,桑德尔灵敏度为0.1767μg·cm-2,平均回收率为100.1%(RSD=1.43%,n=6);2种方法测定样品中烟酸占替诺含量结果一致。结论:所建立的方法反应条件简单、方便快捷,为烟酸占替诺的含量测定提供了新方法。     

Toxic effect of arsenate and cadmium alone and in combination on giant duckweed (Spirodela polyrrhiza L.) in response to its accumulation

To evaluate the biological effects of wastewater samples containing heavy metals, the effects of metal Cd (II) and As (V) were studied on Spirodela polyrrhiza L. The plants were exposed at metal concentrations 0.1, 0.5, 1, 2 microM of Cd (II) and 1, 5, 10, 20 microM of As (V) for a period of 1, 4, 7 d (day) alone and in combination of both. Plants accumulated 1855 mg kg(-1) dw (dry weight) Cd and 1230 mg kg(-1) dw As after 7 d in alone, whereas it was 885 mg kg(-1) dw Cd and 865 mg kg(-1) dw As in combination. The toxicological parameters such as fresh biomass, photosynthetic pigments, and total protein contents increased up to 2 microM of Cd (II) after 1 d and 10 microM of As (V) after 4 d with respect to control (Hormesis effect), followed by gradual decline at higher concentrations and duration. In case of Cd (II) a maximum decrease of 58% in protein content, 62% in fresh biomass, and 78% in total chlorophyll was observed at 2 microM, whereas, with As (V) 38% decrease in protein content, 34% in fresh biomass, and 52% in total chlorophyll was shown at 20 microM after 7 d. The metal tolerance strategy against metal induced reactive oxygen species adopted by the plants was investigated with reference to nonprotein thiols (NP-SH), cysteine, and ascorbic acid. The results of combined treatment revealed reduced toxicity at the level of fresh biomass, protein content, and chlorophyll; however, the amount of nonenzymatic antioxidant did not significantly (P = 0.172) increase as compared to alone treatment. Finally, it was concluded that due to high metal accumulation coupled with defense potential, the plant appears to have a potential for its use as phytoremediator species of aquatic environments.     

Blockade of LTB4-induced chemotaxis by bioactive molecules interfering with the BLT2-Gαi interaction

BLT2, a low-affinity leukotriene B₄ (LTB₄) receptor, is a member of the G-protein coupled receptor (GPCR) family and is involved in the pathogenesis of inflammatory diseases such as asthma. Despite its clinical implications, however, no pharmacological inhibitors are available. In the present study, we screened for small molecules that interfere with the interaction between the third intracellular loop region of BLT2 (BLT2_iL3) and the Gα_i3 protein subunit (Gα_i3), using a high-throughput screening (HTS) assay with a library of 1040 FDA-approved drugs and bioactive compounds. We identified two small molecules—purpurin [1,2,4-trihydroxy-9,10-anthraquinone; IC₅₀ = 1.6 μM for BLT2] and chloranil [tetrachloro-1,4-benzoquinone; IC₅₀ = 0.42 μM for BLT2]—as specific BLT2-blocking agents. We found that blockade of the BLT2_iL3-Gα_i3 interaction by these small molecules inhibited the BLT2-downstream signaling cascade. For example, BLT2-signaling to phosphoinositide-3 kinase (PI3K)/Akt phosphorylation was completely abolished by these molecules. Furthermore, we observed that these small molecules blocked LTB₄-induced chemotaxis by inhibiting the BLT2-PI3K/Akt-downstream, Rac1-reactive oxygen species-dependent pathway. Taken together, our results show that purpurin and chloranil interfere with the interaction between BLT2_iL3 and Gα_i3 and thus block the biological functions of BLT2 (e.g., chemotaxis). The present findings suggest a potential application of purpurin and chloranil as pharmacological therapeutic agents against BLT2-associated inflammatory human diseases.