雷公藤红素对多发性骨髓瘤细胞株RPMI 8226的体外抑制作用研究

目的研究雷公藤红素（Celastrol）对多发性骨髓瘤细胞株RPMI 8226的抑制作用;方法使用CCK-8试剂研究生长抑制作用,使用An-nexin-V/PI双染色法,研究诱导凋亡作用;使用流式细胞仪进行sub-G1峰及细胞周期分析;结果雷公藤红素能够抑制RPMI 8226细胞生长,呈现剂量依赖性,IC50值为1.87μmol.L-1;通过Annexin-V/PI双染色法以及sub-G1峰分析,证实雷公藤红素可以诱导肿瘤细胞凋亡;并使肿瘤细胞的S期细胞减少;结论雷公藤红素可以抑制骨髓瘤细胞株RPMI 8226生长,诱导细胞凋亡,并使S期细胞减少。     

雷公藤红素阻断LP-1人多发性骨髓瘤细胞周期及抑制血管生成的实验研究

目的研究雷公藤红素对于多发性骨髓瘤细胞株LP-1细胞周期及血管生成的影响。方法采用台盼蓝染色法考察雷公藤红素对细胞生长曲线的影响;划痕法检测雷公藤红素对血管内皮细胞体外血管生成能力的影响;采用碘化吡啶(PI)染色法检测雷公藤红素对LP-1多发性骨髓瘤细胞周期的调控作用。结果雷公藤红素作用浓度为2μM时即可引起细胞生长停滞,雷公藤红素对人多发性骨髓瘤LP-1细胞的生长曲线具有明显的抑制作用,这种效应具有明显的剂量-效应关系。雷公藤红素能剂量依赖性地抑制人血管内皮细胞对划痕损伤的修复能力,雷公藤红素1μM作用24 h即可引起划痕修复停滞,并引起部分血管内皮细胞死亡,在作用48 h后对人脐静脉内皮细胞表现出明显的杀伤活性。雷公藤红素以不同浓度作用24 h后随着雷公藤红素浓度增加,人多发性骨髓瘤细胞进入G1期比例明显增多,S期细胞明显减少。结论雷公藤红素能抑制骨髓瘤细胞株的生长,并抑制人脐静脉血管内皮细胞体外血管生成能力;雷公藤红素可将人多发性骨髓瘤LP-1细胞周期阻断于G1期,从而抑制其后续的DNA合成及有丝分裂。     

五环三萜抑制A549细胞生长与促进糖原累积作用的相关性研究

目的:研究五环三萜化合物(齐墩果酸和山楂酸)对人肺腺癌A549细胞的生长是否有抑制作用并对其可能的作用机制即抑制糖原磷酸化酶进行探讨。方法:用MTT法测定不同浓度的化合物对A549细胞生长的抑制作用;通过测定细胞中的糖原含量的变化证实化合物抑制了细胞中糖原磷酸化酶的活性。结果:MTT法测得化合物对A549细胞生长具有抑制作用。同时,测得齐墩果酸和山楂酸对A549细胞的糖原磷酸化酶具有抑制活性,其IC50分别是5.98和4.01μmol.L-1。进一步经化合物处理后的细胞内糖原含量呈现剂量依赖性增加。结论:齐墩果酸和山楂酸具有抑制A549细胞生长的作用,其作用可能是通过抑制细胞内的糖原磷酸化酶活性而实现的。     

龙须菜藻红蛋白抗肿瘤活性的研究

目的探讨龙须菜藻红蛋白抗肿瘤活性。方法体内实验以S180荷瘤小鼠为肿瘤模型,检测藻红蛋白粗提物(CPE)对肿瘤生长的抑制作用以及对免疫器官的影响;体外实验采用MTT法检测不同浓度的藻红蛋白(PE)对人宫颈癌HeLa、人食道癌EC109和人血管内皮细胞等细胞的作用,流式细胞仪、Annexin V-FITC/PI双荧光染色法观察藻红蛋白对HeLa细胞周期及细胞凋亡的影响。结果CPE能显著的抑制小鼠S180肉瘤生长,当灌胃剂量在100~300 mg.kg-1范围内时,呈量效关系,其中剂量为300 mg.kg-1时,其抑瘤率达49%,且能极显著地提高荷瘤小鼠的胸腺指数;体外实验表明PE对人宫颈癌细胞HeLa有明显的抑制作用,其抑制率达70%以上,并存在剂量依赖性。PE可阻滞HeLa细胞从G2/M期进入S期,促使细胞凋亡。但PE对人食道癌EC109细胞无作用,对正常的人血管内皮细胞有一定的促生长作用。结论龙须菜藻红蛋白具有体内抑制S180肉瘤生长的活性,体外对培养的不同细胞作用不同,对人宫颈癌HeLa细胞有较强的抑制作用。     

N-乙酰基色胺的异源生物合成和抑藻活性研究

目的 用Streptomyces lividans GX28异源合成N-乙酰基色胺,并研究N-乙酰基色胺的抗赤潮藻活性。方法 前期研究发现Bacillus atrophaeus C89芳香族氨基酸脱羧酶(aromatic l-amino acid decarboxylase, AADC)能将L-色氨酸脱羧成L-色胺。氨基酸多序列比对发现S. lividans GX28基因组中存在使色胺乙酰化的酶。通过克隆、重组将aadc基因转入S. lividans GX28中构建重组菌株,HPLC检测目标产物,NMR鉴定化合物的结构。检测化合物对3种赤潮微藻的毒性。结果 S. lividans GX28中的蛋白WP_015609847.1含有芳烷基胺N-乙酰转移酶(alkyl amine N-acetyltransferase, AANAT)的底物结合位点(P64和F188)和催化位点(Y168),推测其为AANAT。宿主的发酵产物中分离得到N-乙酰基色胺。N-乙酰基色胺对墨西哥原甲藻的生长具有较强的抑制作用(IC50=9.56mg/L)。结论 推测aadc基因在链霉菌中异源表达。重组链霉菌中检测到N-乙酰基色胺,并对N-乙酰基色胺的生物合成途径进行推测。N-乙酰基色胺对P. mexicanum的生长具有显著的抑制作用。本研究为抑藻化合物的生物合成研究奠定了基础。     

松树皮中原花青素对荷瘤小鼠S_(180)肿瘤细胞抗氧化酶系的影响

目的研究松树皮中原花青素的体内抗肿瘤作用.方法采用小鼠移植性肿瘤模型S180肉瘤考察松树皮原花青素对荷瘤小鼠瘤重的抑制作用,紫外分光光度法测定原花青素对肿瘤细胞CuZn-SOD、GSH-PX活性以及MDA含量的影响,流式细胞仪检测原花青素对肿瘤细胞中活性氧含量的影响.结果松树皮原花青素对肿瘤细胞有较强的抑制作用,120mg·kg-1的剂量能显著抑制荷瘤小鼠S180肉瘤的生长,抑瘤率达49.73%;对S180肿瘤细胞中CuZn-SOD、GSH-PX活性有一定的作用,其中高剂量能够显著性的提高其活性;能够降低肿瘤细胞中MDA的含量,防止脂质过氧化的发生.结论松树皮原花青素通过抑制肿瘤的生长,保护正常细胞,减少自由基对正常细胞的伤害而达到抗肿瘤作用.     

多胺类似物CPENSpm通过干扰多胺代谢抑制肺癌细胞的增殖

目的研究多胺类似物CPENSpm对肺癌细胞株A549增殖和细胞凋亡的影响,以探讨CPENSpm抗肿瘤的作用机制。方法MTS法分析细胞的增殖速度,化学分析法测定多胺代谢酶的活性,HPLC法分析细胞内的多胺含量,亚凋亡峰测定法和DNA片段化分析法鉴定细胞程序性凋亡。结果CPENSpm处理A549肺癌细胞可导致:①癌细胞生长抑制并激发细胞凋亡;②抑制多胺合成关键酶ODC的活性,活化多胺降解代谢关键酶SSAT和SMO的活性;③耗竭细胞内多胺含量。SMO抑制剂MDL72527可拮抗CPENSpm对A549细胞的生长抑制作用。结论CPENSpm通过干扰A549细胞的多胺代谢途径,耗竭肿瘤快速生长必需的多胺成分,诱导产生活性氧H2O2从而抑制癌细胞生长并激发细胞程序性凋亡。     

海洋弧菌B2817的抗肿瘤活性成分研究

目的 对海洋弧茵B2817的抗肿瘤活性成分进行分离纯化和结构鉴定.方法采用溶剂萃取、制备HPLC等分离手段.对该菌株所产的活性成分进行了活性追踪分离.通过现代波谱学手段进行化学结构鏊定,以MTT法评价了化合物的抗肿瘤活性.结果从中分离得到4个化合物.分别鉴定为灵茵红素(1)、肉豆蔻酸(2)、7-十六碳烯酸(3)、7,10-十八碳二烯酸(4).化合物1对肿瘤细胞SM7721、S180具有强细胞毒活性.IC50分别为6.3、5.6μg·mL-1,而对人正常肝细胞HL-02无毒性.结论 4个化合物均为首次从该菌株中得到,而且弧菌B2817为灵茵红素的生产提供了新的来源.     

新天然来源抗生素-抗霉素A18的抗肿瘤活性及其产生菌107A-01824的生物学特征

目的 检测抗霉素A18的体外抗肿瘤活性并对其产生菌107A-01824的形态及培养特征,生理生化特征等进行研究方法用MTT法检测抗霉素A18的肿瘤细胞生长抑制作用,用流式细胞术测定其对细胞周期的影响:按分类学常规方法研究株107A-01824的形态及部分生理生化特征.结果 抗霉素A18能够抑制人肝癌细胞HepG2、人口腔上皮癌细胞KB的生长:这个细胞株均被阻滞在细胞周期的S期.菌株I07A-01824的形态及培养特征与己知种-黄白链霉菌(Streptomyces albidofavus)一致.结论 红树林内生放线菌是新抗生素的重要来源.     

雷公藤红素对人肺癌A549细胞增殖活性及能量代谢的影响

目的 探究雷公藤红素对人肺癌细胞（A549）的增殖活性以及能量代谢的影响。方法 噻唑蓝(MTT)法和生长曲线检测雷公藤红素对细胞的增殖抑制情况;HE染色观察细胞形态变化;分光光度法测定糖酵解途径中己糖激酶（HK）、丙酮酸激酶（PK）、乳酸脱氢酶（LDH）活力和三羧酸循环中琥珀酸脱氢酶（SDH）活力及能量代谢终产物ATP的含量。结果 雷公藤红素对A549细胞有增殖抑制作用,浓度在2 μg?mL^-1时,对A549细胞的抑制率达到62.71%,远远大于阳性药组5-FU的抑制率;生长曲线结果显示,雷公藤红素作用第4天细胞浓度最低,第6天细胞抑制程度最明显;HE结果表明雷公藤红素处理48 h后,细胞形态变圆,体积缩小,核深染且颜色变深;试剂盒检测结果显示,雷公藤红素非常显著的降低乳酸脱氢酶酶活力（P<0.01）,显著降低琥珀酸脱氢酶活力和ATP含量均显著降低(P<0.05),但对己糖激酶和丙酮酸激酶无明显作用。结论 雷公藤红素能够显著降低人肺癌A549细胞中乳酸脱氢酶和琥珀酸脱氢酶的活力,干扰能量代谢,抑制能量ATP生成,达到抑制A549细胞增殖的作用。     

Fate and distribution of brevetoxin (PbTx) following lysis of Karenia brevis by algicidal bacteria, including analysis of open A-ring derivatives

Flavobacteriaceae (strain S03) and Cytophaga sp. (strain 41-DBG2) are algicidal bacteria active against the brevetoxin (PbTx)-producing, red tide dinoflagellate, Karenia brevis. Little is known about the fate of PbTx associated with K. brevis cells following attack by such bacteria. The fate and distribution of PbTx in K. brevis cultures exposed to these algicidal strains were thus examined by receptor binding assay and liquid chromatography/mass spectrometry (LC/MS) in three size fractions (>5, 0.22–5, <0.22 μm) over a 2-week time course. In control cultures, brevetoxin concentrations in the >5 μm particulate size fraction correlated with changes in cell density, whereas significant increases in dissolved (i.e., <0.22 μm) toxin were observed in the later stages of culture growth. Exposure of K. brevis to either of the two algicidal bacteria tested caused cell lysis, coinciding with a rapid decline in the >5 μm PbTX size fraction and a simultaneous release of dissolved toxin into the growth medium. Upon cell lysis, dissolved brevetoxin accounted for ca. 60% of total toxin and consisted of 51–82% open A-ring derivatives. Open A-ring PbTx-2 and PbTx-3 derivatives bound with lower affinity (approximately 22- and 57-fold, respectively) to voltage-gated sodium channels and were considerably less cytotoxic (86- and 142-fold, respectively) to N2A cells than their individual parent toxins (i.e., PbTx-2 and PbTx-3). These novel findings of changes in PbTx size-fractioned distribution and overall reduction in K. brevis toxicity following attack by algicidal bacteria improve our understanding of potential trophic transfer routes and the fate of PbTx during red tide events. Moreover, this information will be important to consider when evaluating the potential role of algicidal bacteria in harmful algal bloom (HAB) management strategies involving control of bloom populations.     

Malformin C,an algicidal peptide from marine fungus Aspergillus species

Ecotoxicology - A natural compound with the algicidal effect was isolated from the culture medium of Aspergillus sp. SCSIOW2 and was identified as malformin C, which was based on the data of...     

Enhanced efficacy of TD53, a novel algicidal agent, against the harmful algae via the liposomal delivery system

The present study aimed to design the liposomal delivery system for TD53, a novel algicial drug in order to improve the delivery properties of TD53 and evaluate its algicidal effects as well as selectivity against harmful and non-harmful algae. Liposomes of TD53 were prepared with 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) by a lyophilization, resulting in relatively small size vesicles (234±38nm) and narrow size distribution (PI=0.130±0.027). The drug leakage from the liposome was negligible in the F/2 media (<2% during 96h incubation). Subsequently algicidal activity of liposomal TD53 against harmful and nonharmful algae was evaluated at various concentrations. The IC(50) values of TD53 in liposome against harmful algae such as Chattonella marina, Heterosigma akashiwo and Cocholodinium polykrikoides were 2.675, 2.029, and 0.480μM, respectively, and were reduced by approximately 50% compared to those obtained from non-liposomal TD53. In contrast, the algicidal effect of liposomal TD53 was insignificant against non-harmful algae including Navicula pelliculosa, Nannochloropsis oculata and Phaeodactylum EPV. Those results suggested that liposomal delivery systems might be effective to enhance the efficacy of TD53 while maintaining the selectivity to harmful algal species.     

浙江沿海海洋细菌抗菌活性及代谢产物的初步研究

目的 对浙江沿海海洋细菌进行抗菌活性筛选,并初步研究活性菌株代谢产物的结构.方法 用琼脂块法进行抗菌活性筛选,利用高效液相等手段对其代谢产物进行分离纯化,利用核磁共振和质谱等手段对活性化合物进行结构鉴定.结果 与结论共发现31株活性菌株,选择其中6株活性菌株进行研究,对其中活性较强的5个化合物进行结构鉴定,初步确定其化...     

Novel bioactive metabolites from a marine derived bacterium Nocardia sp. ALAA 2000

Extracts of the Egyptian marine actinomycete, Nocardia sp. ALAA 2000, were found to be highly bioactive. It was isolated from the marine red alga Laurenica spectabilis collected off the Ras-Gharib coast of the Red Sea, Egypt. According to detailed identification studies, the strain was classified as a member of the genus Nocardia. The cultivation and chemical analysis of this species yielded four structurally related compounds namely, chrysophanol 8-methyl ether (1), asphodelin; 4,7'-bichrysophanol (2) and justicidin B (3), in addition to a novel bioactive compound ayamycin; 1,1-dichloro-4-ethyl-5-(4-nitro-phenyl)-hexan-2-one (4) which is unique in contain both chlorination and a rarely observed nitro group. The compounds were isolated by a series of chromatographic steps and their structures of 1~3 secured by detailed spectroscopic analysis of the MS and NMR data whereas that of 4 was elucidated by single crystal X-ray diffraction studies. These compounds displayed different potent antimicrobial activity against both Gram-positive and Gram-negative bacteria as well as fungi with MIC ranging from 0.1 to 10 mug/ml.     

A new hTopo I isomerase inhibitor produced by a mangrove endophytic fungus no. 2240.

A new hTopo I isomerase inhibitor, (+)-3,3',7,7',8,8'-hexahydroxy-5,5'-dimethylbianthraquinone (2240A), was isolated from the mangrove endophytic fungus no. 2240 collected from an estuarine mangrove at the South China Sea coast. Its structure was elucidated by spectral analyses including two-dimensional NMR, HR-EI-MS, IR, and UV. The hTopo I isomerase inhibition experiment showed that 2240A (1) possessed strong inhibiting activity. When its inhibition concentration was 4.65 mumol/l, its percent inhibition rate was 59.1%, while the lowest inhibition concentration of the positive control camptothecin was 1.00 x 10(3) mumol/l.     

A new hTopo I isomerase inhibitor produced by a mangrove endophytic fungus no. 2240

A new hTopo I isomerase inhibitor, (+)-3,3',7,7',8,8'-hexahydroxy-5,5'-dimethylbianthraquinone (2240A), was isolated from the mangrove endophytic fungus no. 2240 collected from an estuarine mangrove at the South China Sea coast. Its structure was elucidated by spectral analyses including two-dimensional NMR, HR-EI-MS, IR, and UV. The hTopo I isomerase inhibition experiment showed that 2240A (1) possessed strong inhibiting activity. When its inhibition concentration was 4.65 micromol/l, its percent inhibition rate was 59.1%, while the lowest inhibition concentration of the positive control camptothecin was 1.00 x 10(3) micromol/l.     

香豆素苯并三唑的合成、抗微生物活性及其与氯霉素和氟康唑协同作用研究

以间苯二酚为起始原料,经过环化、醚化、N-烷化等多步反应合成了一系列新型香豆素苯并三唑类化合物,其结构经1H NMR、IR、MS和元素分析证实。体外考察了合成的香豆素类化合物抗革兰阳性菌、革兰阴性菌及真菌活性。结果表明香豆素苯并三唑能有效抑制细菌和真菌的生长,其中化合物11a～11e和13a～13c抗普通变形杆菌ATCC 6896活性强于氯霉素(chloromycin)。化合物11a和11b抑制金葡菌ATCC 25923和藤黄微球菌ATCC 4698的生长能力与氯霉素相当。化合物11a～11d抗烟曲霉菌ATCC 96918活性优于氟康唑(fluconazole)。此外,氯霉素或氟康唑与香豆素苯并三唑联用后,不仅减少了用药剂量,还拓宽了抗微生物谱,尤其增强了抑制耐甲氧西林的金葡菌N 315和氟康唑不敏感的烟曲霉菌的生长能力。     

Isolation and Characterization of Berberine from Ceriops decandra Mangrove Plant Species

Pharmaceutical Chemistry Journal - Isolation and characterization of antigastric cancer bioactive compound berberine from Ceriops decandra mangrove plant species are reported. The plant is used in...     

南海红树林海泥中分离的抗真菌放线菌No.H75-11活性成分研究

目的对我国南海红树林底泥来源的一株放线菌中的抗真菌活性成分进行研究。方法以深部真菌感染的主要致病菌白色念珠菌(Candida albicans)为指示菌,采用琼脂扩散法和硅胶柱、Sephadex LH-20等层析手段进行活性追踪分离。结果从抗真菌活性菌No.H75-11中分离得到6个化合物,采用波谱学手段鉴定其结构分别为:过氧化麦角甾醇(1)、尿嘧啶(2)、[N,N-′(3,3′-二乙基二氨基甲酸酯)-(4,4′-二甲基)]-二苯基脲(3)、抗霉素Aa1(4)、抗霉素Aa2(5)和4-(2-羟基乙氧基)-3-甲氧基-苯甲酸(6)。结论化合物4和5为抗霉素(antimycin)家族成员,初步的活性测试表明其对白色念珠菌显示出明显的抑菌活性,化合物3与6为首次从天然界分离得到,本文首次报道了它们的核磁数据。