高效液相色谱法测定康得灵胶囊中黄芩苷的含量

目的 建立康得灵胶囊中黄芩苷的HPLC测定方法。方法 色谱柱为Agilent Tc-C₁₈色谱柱（4.6 mm×250 mm,5 μm）,柱温为30 ℃;流动相为乙腈-0.5‰磷酸溶液（26：74）,流速为1.0 ml/min,检测波长265 nm。结果 黄芩苷保留时间约为16 min。以峰面积（Y）对进样浓度（X, μg/ml）线性回归,得回归方程：Y=22 114.67 X－112 836.7,r=0.998 8,线性范围5.410~108.2 μg/ml。平均加样回收率为98.78%,RSD为0.74%。结论 本方法操作简便,测定结果准确可靠,可用于康得灵胶囊中黄芩苷的含量测定。     

高效液相色谱法测定新保肾片中芦荟大黄素、大黄酸、大黄素、大黄酚和大黄素甲醚的含量

目的 建立新保肾片中芦荟大黄素、大黄酸、大黄素、大黄酚和大黄素甲醚的含量测定方法,为生产质量提供保障。方法 采用高效液相色谱法测定,色谱柱为Lichrospher-C₁₈柱(250 mm ×4.6 mm,5 μm),流动相为甲醇:0.1%磷酸溶液(7030),流速为1.0 ml/min,柱温为35 ℃,检测波长为254 nm。结果 芦荟大黄素、大黄酸、大黄素、大黄酚和大黄素甲醚分别在2.30~18.4 μg/ml(r=1.0)、2.930~23.44 μg/ml(r=1.0)、5.00~40.0 μg/ml(r=1.0)、14.870~118.96 μg/ml (r=0.999 8)、7.410~59.28 μg/ml(r=0.999 9)范围内有良好的线性关系,平均回收率分别为100.16%、102.91%、99.76%、100.32%、100.44%,RSD分别为1.58%、1.27%、1.67%、1.33%、1.03%(n=9)。结论 该方法准确易行,便于质量控制。     

高效液相色谱法测定麻杏口服液中盐酸麻黄碱及盐酸伪麻黄碱的含量

目的 建立HPLC法测定麻杏口服液中盐酸麻黄碱及盐酸伪麻黄碱的含量。 方法 采用Phenomenex Hydro-RP (250 mm×4.6 mm,4 μm)色谱柱,以乙腈(A)-0.1%磷酸溶液(含0.1%三乙胺)(B)为流动相,梯度洗脱(0~20 min,3%→10% A),流速:1.0 ml/min,检测波长:210 nm,进样量:20 μl。 结果 盐酸麻黄碱在0.99~39.6 μg/ml范围内线性关系良好,r=0.999 9, 平均回收率为101.5%,RSD为1.77%(n=6);盐酸伪麻黄碱在1.09~43.6 μg/ml范围内线性关系良好,r= 0.999 9,平均回收率为100.8%, RSD为 1.96%(n=6)。 结论 本法简便、可靠、准确,可用于该制剂的质量控制。     

草血竭低极性部位化学成分的气相色谱-质谱法分析

目的 研究草血竭(Polygonum paleaceum Wall)低极性部位的主要化学成分。 方法 草血竭用乙醇提取,提取液回收乙醇后用石油醚萃取,采用气相色谱-质谱法(GC-MS)对草血竭低极性部位进行分析测定,与标准谱库进行比较分析,并用峰面积归一化法计算各成分的质量百分数。 结果 共检出40个化学成分,其中主要成分β-瑟林烯和反油酸乙酯含量较高。 结论 草血竭低极性部位主要成分为β-瑟林烯(59.32%)和反油酸乙酯(27.02%),并含有棕榈酸(4.18%)、13,27-cycloursan-3-one(2.55%)、顺式-11-二十碳烯酸(1.31%)等化学成分。     

高效液相色谱法测定壮骨颗粒中补骨脂素与异补骨脂素的含量

目的 建立高效液相色谱法测定壮骨颗粒中补骨脂素和异补骨脂素的含量。方法 色谱柱为Agilent Zorbax C₁₈柱（4.6 mm×250 mm,5 μm）,流动相为甲醇-水（45：55）,检测波长为245 nm,流速为1.0 ml/min,柱温为25 ℃,进样量为10 μl。采用70%乙醇水浴方法提取壮骨颗粒中的补骨脂素和异补骨脂素。结果 补骨脂素与异补骨脂素在3.75~40 μg/ml范围内呈良好的线性关系,对方法精密度（n=6）、重复性（n=6）和稳定性（12 h）进行考察,相对标准偏差（RSD）均小于2%。加样回收率（n=6）为94%~105%。结论 该测定方法简便、快速、准确,可用于壮骨颗粒的临床快速质量控制。     

高效液相色谱法测定山楂精降脂片中齐墩果酸和熊果酸含量

目的 建立高效液相色谱法(HPLC)测定山楂精降脂片中齐墩果酸和熊果酸的含量,有效地控制产品质量。 方法 采用Agilent Zorbax SB C₁₈ 柱(250 mm×4.6 mm,5 μm),以甲醇-0.06 mol/L乙酸铵(85:15)为流动相,流速为0.8 ml/min;检测波长为210 nm;柱温为25 ℃。 结果 齐墩果酸和熊果酸分别在0.124~2.48 μg(r=0.999 7)和0.498~9.96 μg(r=0.999 8)范围内与其峰面积呈良好线性关系。测得齐墩果酸平均回收率为96.9%,RSD为1.26%;熊果酸平均回收率为100.4%,RSD为2.6%。 结论 山楂精降脂片质量稳定,质控方法简便、准确,结果可靠、重现性好 。     

复方生化颗粒的定性鉴别和含量测定研究

目的 提高复方生化颗粒的质量标准。方法 采用薄层色谱（TLC）法对处方中的甘草、丹参进行定性鉴别;采用高效液相色谱（HPLC）法鉴别苦杏仁苷;采用HPLC法测定处方中的丹酚酸B含量,色谱柱为Agilent HC-C₁₈（4.6 mm×250 mm,5 μm）,流动相为乙腈-0.1%磷酸（23：77）,流速为1.0 ml/min,检测波长为286 nm,柱温为30 ℃。结果 TLC斑点清晰,分离度较好,专属性强,阴性对照无干扰;HPLC法定性鉴别更加准确、可靠与客观;丹酚酸B在1.56~49.92 μg/ml范围内浓度与峰面积呈良好的线性关系（r=0.999 9）,平均回收率为100.07%,RSD为1.61%（n=9）。结论 建立的方法准确、可靠,重复性好,可用于复方生化颗粒的质量控制。     

清热败毒颗粒剂的质量标准研究

目的 建立清热败毒颗粒剂的质量标准。方法 采用薄层色谱法（TLC）鉴别处方中的板蓝根、连翘、紫花地丁和甘草,采用高效液相色谱法（HPLC）测定绿原酸的含量,色谱柱为Agilent ZORBAX SB-C₁₈柱（4.6 mm×250 mm,5 μm）;流动相为乙腈（A）与含0.2%甲酸的水溶液（B）,梯度洗脱：0~12 min,11%~12%A;流速：1.0 ml/min;柱温：30 ℃;检测波长：327 nm;进样量：20 μl。结果 薄层鉴别色谱中特征斑点明显,专属性强。绿原酸在6.19~396.00 μg/ml浓度范围内呈良好线性关系,其回归方程为Y=60.239 4X+9.096 3（r>0.999 9）,回收率为99.66%（RSD=2.82%）。结论 该法简便、稳定可靠、重复性好,为控制清热败毒颗粒的质量标准提供了可借鉴的依据。     

高效液相色谱法测定降脂护肝胶囊中葛根素的含量

目的 建立高效液相色谱法测定降脂护肝胶囊中葛根素的含量。方法 色谱柱为Waters Symmetry C₁₈柱（4.6 mm×250 mm,5 μm）,流动相为乙腈-1%甲酸（11：89）,检测波长250 nm,流速1.0 ml/min,柱温30 ℃,进样量10 μl。结果 葛根素在2~40 μg/ml范围内（r=0.999 8）呈良好的线性关系,精密度实验中RSD均小于2%,加样回收率在98%~103%。结论 该测定方法简便、准确,分离效果好,可用于降脂护肝胶囊的质量控制。     

复方颠茄合剂质量标准研究

目的 提高复方颠茄合剂的质量控制标准。方法 采用薄层色谱法（TLC）对复方颠茄合剂中的吗啡进行定性鉴别;采用高效液相色谱法（HPLC）测定复方颠茄合剂中吗啡的含量。以WondaSil C₁₈（4.6 mm×150 mm,5 μm）为色谱柱;A相：0.01 mol/L磷酸二氢钾溶液-0.002 5 mol/L庚烷磺酸钠溶液（含0.1%三乙胺,磷酸调pH至2.5）,B相：乙腈,A∶B=90∶10为流动相;流速：1.0 ml/min;检测波长：220 nm;柱温：30 ℃。结果 在TLC图谱中可检出吗啡的特征斑点。吗啡在0.525~10.5 μg/ml范围内与其峰面积线性关系良好（r=0.999 9）,平均回收率为99.44%,RSD= 0.23%（n=9）。结论 本方法简便准确,专属性强,能够用于复方颠茄合剂的含量测定和质量控制。     

Genetic regulation of the ramA locus and its expression in clinical isolates of Klebsiella pneumoniae

Tigecycline resistance has been attributed to ramA overexpression and subsequent acrA upregulation. The ramA locus, originally identified in Klebsiella pneumoniae, has homologues in Enterobacter and Salmonella spp. In this study, we identify in silico that the ramR binding site is also present in Citrobacter spp. and that Enterobacter, Citrobacter and Klebsiella spp. share key regulatory elements in the control of the romA-ramA locus. RACE (rapid amplification of cDNA ends) mapping indicated that there are two promoters from which romA-ramA expression can be regulated in K. pneumoniae. Correspondingly, electrophoretic binding studies clearly showed that purified RamA and RamR proteins bind to both of these promoters. Hence, there appear to be two RamR binding sites within the Klebsiella romA-ramA locus. Like MarA, RamA binds the promoter region, implying that it might be subject to autoregulation. We have identified changes within ramR in geographically distinct clinical isolates of K. pneumoniae. Intriguingly, levels of romA and ramA expression were not uniformly affected by changes within the ramR gene, thereby supporting the dual promoter finding. Furthermore, a subset of strains sustained no changes within the ramR gene but which still overexpressed the romA-ramA genes, strongly suggesting that a secondary regulator may control ramA expression.     

In vitro Studies of Antimicrobial Activity of Crude Extracts of the Indian Grasses Dhaman (Cenchrus ciliaris) and Kala-Dhaman (Cenchrus setigerus)

The aim of present study was to investigate the antimicrobial activity of Cenchrus ciliaris and Cenchrus setigerus extracts in order to use it as a possible source for new antimicrobial substances against important human pathogens. Crude extracts of the stem of Cenchrus ciliaris and Cenchrus setigerus were evaluated against some medically important pathogens viz. Escherichia coli, Raoultella planticola, Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis, Enterobacter aerogenes, Candida albicans and Aspergillus flavus. The dried and powdered stems were successively extracted with hexane, toluene, isopropyl alcohol, acetone and ethanol using soxhlet assembly. The antimicrobial activity assay was done by both disc diffusion and serial dilution methods. Isopropyl alcohol extract of Cenchrus setigerus showed highest activity against Escherichia coli. The test pathogens were more sensitive to the isopropyl alcohol, acetone and ethanol extracts than to the hexane and toluene extracts except against Bacillus subtilis. Result reveals that the most bioactive compound was cycloleucolenol-9,19-cycloergost-24 (28)-en-3-ol, 4, 14-dimethyl acetate in both the species of Cenchrus grass, (19.15%) in isopropanol extract of Cenchrus setigerus whereas, (14.03%) in acetone extract of Cenchrus ciliaris.     

Cytotoxic fungi--an overview.

Among fungal toxins causing organ damage in the human body, amatoxins and orellanine remain exceptional. Amatoxins, a group of bicyclic octapeptides occurring in some Amanita, Galerina and Lepiota species, induce deficient protein synthesis resulting in cell death, but might also exert toxicity through inducing apoptosis. Target organs are intestinal mucosa, liver and kidneys. Poisoning will result in dehydration and electrolyte derangement, liver necrosis and possibly kidney damage. In established poisoning the mainstay of treatment is optimum symptomatic and supportive care. No specific treatment is available, but some pharmaceuticals, like silibinin, benzylpenicillin and acetylcysteine, might have a role in limiting the extent of hepatic damage. Orellanine is a nephrotoxic bipyridine N-oxide found in some Cortinarius species. Its mechanism of action is not fully understood, but it has been shown to inhibit protein synthesis and to generate free oxygen radicals. As early symptoms often are lacking or vague, poisoning may initially be overlooked or misinterpreted and the patients usually present with established renal damage. Supportive care is the only therapeutic option. Tricholoma equestre might contain a myotoxin and repeated ingestion may cause significant rhabdomyolysis. Ingestion of Amanita smithiana and A. proxima has been reported to result in kidney damage. Gyromitrin, a toxic compound that is converted to hydrazines in the stomach, occurs in some Gyromitra species. It is mainly neurotoxic, but may also induce moderate hepatic damage and haemolysis.     

Toxic dinoflagellates (Dinophyceae) from Rarotonga, Cook Islands

Dinoflagellate species isolated from the green calcareous seaweed, Halimeda sp. J.V. Lamouroux, growing in Rarotongan lagoons, included Gambierdiscus australes Faust & Chinain, Coolia monotis Meunier, Amphidinium carterae Hulburth, Prorocentrum lima (Ehrenberg) Dodge, P. cf. maculosum Faust and species in the genus Ostreopsis Schmidt. Isolates were identified to species level by scanning electron microscopy and/or DNA sequence analysis. Culture extracts of G. australes isolate CAWD149 gave a response of 0.04 pg P-CTX-1 equiv. per cell by an N2A cytotoxicity assay (equivalent to ca 0.4 pg CTX-3C cell⁻¹). However, ciguatoxins were not detected by LC-MS/MS. Partitioned fractions of the cell extracts potentially containing maitotoxin were found to be very toxic to mice after intraperitoneal (i.p.) injection. A. carterae was also of interest as extracts of mass cultures caused respiratory paralysis in mice at high doses, both by i.p. injection and by oral administration. The Rarotongan isolate fell into a different clade to New Zealand A. carterae isolates, based on DNA sequence analysis, and also had a different toxin profile. As A. carterae co-occurred with G. australes, it may contribute to human poisonings attributed to CTX and warrants further investigation. A crude extract of C. monotis was of low toxicity to mice by i.p. injection, and an extract of Ostreopsis sp. was negative in the palytoxin haemolysis neutralisation assay.     

Toxicity assessment of crude and partially purified extracts of marine Synechocystis and Synechococcus cyanobacterial strains in marine invertebrates

Among the Cyanoprokaryota, the genera Synechocystis and Synechococcus have rarely been studied with respect to potential toxicity. This is particularly true with marine environments where studies about the toxicity of cyanobacteria are restricted to filamentous forms at the warmer temperate and tropical regions and also to filamentous forms at cold seas such as the Baltic Sea. In this study, we describe the effects of cyanobacterial strains of the Synechocystis and Synechococcus genera isolated from the marine coast of Portugal, on marine invertebrates. Crude and partially purified extracts at a concentration of 100 mg/ml of freeze-dried material of the marine strains were tested for acute toxicity in nauplii of the brine shrimp Artemia salina, in the rotifer Brachionus plicatillis and in embryos of the sea urchin Paracentrotus lividus and the mussel Mytilus galloprovincialis. The cyanobacterial extracts, especially the crude extract, had an impact on A. salina nauplii. No significant toxic effects were registered against the rotifer. A negative impact of all strains was recorded on the embryonic development of the sea urchin, with toxic effects resulting in an inhibition of embryogenesis or development of smaller larvae. To the mussel embryos, the effects of cyanobacterial extracts resulted in a complete inhibition of embryogenesis. The results of all assays indicate that Synechocystis and Synechococcus marine strains contained toxic compounds to marine invertebrates.     

Effect of Plant Extracts Formulated in Different Ointment Bases on MDR Strains

Extracts of Aloe vera whole plant, Eucalyptus globulus leaves, Ficus infectoria bark, Ficus religiosa bark and Piper betel leaves were studied for antibacterial activity on resistant and sensitive strains, isolated from skin and soft tissue infections. A combination of hot alcoholic extracts of Ficus infectoria, Ficus religiosa and Piper betel were found to be more effective against all the isolates. The combined extract was formulated in different ointment bases such as polyethylene glycol, gelatin, sodium alginate, carbopol, cream base and honey. These were then evaluated to find a suitable base for preparation of an ointment. In vitro study of the release of antimicrobials and kill-time studies of the herbal ointments was carried out against multi-drug resistant isolate of Pseudomonas. The ointment showed bactericidal activity within 2 h against the resistant strain of Pseudomonas spp.     

Structure-Based Design of Substituted Piperidines as a New Class of Highly Efficacious Oral Direct Renin Inhibitors

相似文献   

Toxigenicity of enniatins from Western Australian Fusarium species to brine shrimp (Artemia franciscana)

The high prevalence (14 of 24 isolates) of enniatin-producing isolates from Western Australian Fusarium species isolated from pasture legumes associated with sheep feed refusal and rat deaths, and the high toxicity of their crude extracts to brine shrimp (Artemia franciscana) from a previous study warranted further investigation of this class of mycotoxin. Crude extracts from Fusarium acuminatum, Fusarium avenaceum, Fusarium tricinctum and Fusarium sambucinum, along with enniatins A, A1, B and B1 purified from a Western Australian strain of F. acuminatum using semi-preparative HPLC, were bioassayed using brine shrimp. All Fusarium isolates produced both enniatins B and B1, except for F. tricinctum WAC 8019, and 11 of the 17 isolates produced enniatin A1. Overall, all of the F. avenaceum isolates produced high amounts of enniatins, in particular enniatin B. One isolate of F. acuminatum (WAC 5715) and of F. tricinctum (WAC 11486) also produced high amounts of both enniatins B and B1. Only F. acuminatum WAC 5715 produced enniatin A among the tested isolates. All four purified enniatins A, A1, B, B1, individually and in combination, caused brine shrimp toxicity after 6 h of exposure, implicating that this emerging class of mycotoxin as a cause of the acute toxicity to brine shrimp observed. The mixture of all four enniatins was the most toxic to brine shrimp compared to purified individual enniatins, where the relative toxicity order was B > B1 > A1 > A. Enniatin B was the individual most toxic enniatin with some bioactivity at 5 μg/mL and almost 100% brine shrimp death at 50 μg/mL after 24 h of exposure. This study is the first report to confirm the acute toxicity of enniatins A, A1, B and B1 to brine shrimp, and also highlights the need for further investigation of the potential toxicity of these cyclic hexadepsipeptides to animals and humans.     

Hormetic Responses of Lonicera Japonica Thunb. To Cadmium Stress

The hormetic responses of Lonicera japonica Thunb. to cadmium (Cd) stress were investigated in a hydroponic experiment. The present results showed that root length and total biomass dry weight increased in comparison with the control at low concentrations Cd. The height of the plant exposed to 2.5 and 5 mg L^-1 Cd increased significantly by 11.9% and 12.8% relative to the control, and with the increase of Cd concentrations in the medium, plant height began to decrease. The responses of photosynthetic pigments contents and relative water content to Cd stress had a similar trend, which all showed significantly an inverted U-shaped dose–response curve and confirmed that the stimulatory effect of low concentrations Cd occurred in the plant. Furthermore, L. japonica, as a new Cd-hyperaccumulator, could be considered as a new plant model to study the underlying mechanisms of the hormesis.     

Toxic activities of Brazilian centipede venoms

Centipedes have a venom gland connected to a pair of forceps, which are used to arrest preys. Human victims bitten by centipedes usually manifest burning pain, paresthesia and edema, which may develop into superficial necrosis. The aim of this work was to characterize and compare toxic activities found in venoms of three species of Brazilian centipedes-Otostigmus pradoi, Cryptops iheringi and Scolopendra viridicornis. By SDS-PAGE (4-20%), important differences were noticed among venoms (between 7 and 205kDa). Few bands showed feeble caseinolytic, fibrinogenolytic and gelatinolytic activities by zymography, but strong hyaluronidase activity was observed in S. viridicornis and O. pradoi venoms. In addition, such activities could be inhibited by o-phenanthroline, indicating that these enzymes are metalloproteinases. All venoms induced nociception, edema and myotoxicity in mice, but only S. viridicornis induced mild hemorrhagic activity. No coagulant activity was detected in centipede venoms. Low phospholipase A(2) activity was observed exclusively in S. viridicornis and O. pradoi venoms, but these venoms had intense direct hemolytic activity on human erythrocytes. Cross-reactivity among venoms was observed using species-specific sera raised in rabbits. Differences were noticed among centipede venoms, but S. viridicornis is indeed the most toxic venom and thereby it could induce a more severe envenomation.