Antimutagenicity of a suberin extract from Quercus suber cork

The possible protective effect of a suberin extract from Quercus suber cork on acridine orange (AO)-, ofloxacin- and UV radiation-induced mutagenicity (bleaching activity) in Euglena gracilis was examined. To our knowledge, the present results are the first attempt to analyse suberin in relation to mutagenicity of some chemicals. Suberin exhibits a significant dose-dependent protective effect against AO-induced mutagenicity and the concentration of 500 μg/ml completely eliminates the Euglena-bleaching activity of AO. The mutagenicity of ofloxacin is also significantly reduced in the presence of suberin (125, 250 and 500 μg/ml). However, the moderate protective effect of suberin on UV radiation-induced mutagenicity was observed only at concentrations 500 and 1000 μg/ml. Our data shows that suberin extract from Q. suber cork possess antimutagenic properties and can be included in the group of natural antimutagens acting in a desmutagenic manner.     

睡菜离体快繁技术的研究

以睡菜的幼嫩茎段为外植体,接种到附加不同浓度激素配比(6-BA/NAA)的MS培养基,诱导睡菜愈伤组织、芽及根的生长。研究发现,外植体在1.0mg/L 6-BA+0.1mg/L NAA+MS的培养基上培养10d,可观察到浅绿色的愈伤组织。愈伤组织转接到4.0mg/L 6-BA+0.3mg/L NAA+MS培养基上2周左右可生成芽。对带芽的愈伤组织再进行诱导生根进而形成完整再生植株,最适根诱导培养基为0.3mg/L 6-BA+1.0mg/L NAA+MS培养基。该实验采用植物离体快繁技术成功建立了睡菜再生体系,为睡菜种苗规模化奠定了技术基础。     

丁香(Syringa L.)种间杂交幼胚离体培养研究

采用幼胚离体培养方法克服幼胚败育从而直接获得杂种实生苗,对影响丁香幼胚培养成功的各种因子作了较系统的研究.结果表明,丁香幼胚培养的最适培养基为Monnier;最佳糖浓度为50g·L^-1;幼胚在50～60d胚龄时培养最容易成功;加入适量的椰乳、谷氨酰胺或谷氨酸及活性炭可以促进幼胚的萌发和生长.低浓度(0.01mg·L^-1)BA的加入可以提高幼胚的萌发率;NAA浓度以0.01mg·L^-1为最佳.     

Influence of in vitro growth conditions on in vitro and ex vitro photosynthetic rates of easy- and difficult-to-acclimatize sea oats (Uniola paniculata L.) genotypes

Net photosynthetic rates (P _n) of easy (EK 16-3) and difficult-to-acclimatize (EK 11-1) sea oats genotypes were examined under the following culture conditions: (1) photoautotrophic [sugar-free medium, high photosynthetic photon flux (PPF), high vessel ventilation rates and CO₂ enrichment, (PA)]; (2) modified photomixotrophic [sugar-containing medium diluted with sugar-free medium over time, high PPF, and high vessel ventilation rates (PM)]; (3) modified photomixotrophic enriched [same as PM with CO₂ enrichment, (PME)]; or (4) conventional photomixotrophic [sugar-containing medium, low PPF, and low vessel ventilation rates (control)]. Regardless of genotype, plantlets cultured under PA conditions died within 2 wk, whereas under PM and PME conditions, plantlets increased their P _n. After 6 wk, P _n per gram dry weight was 1.7 times greater in EK 16-3 than EK 11-1 plantlets cultured under PME conditions. In vitro-produced leaves of EK 16-3 plantlets were elongated with expanded blades, whereas EK 11-1 produced short leaves without expanded blades, especially under control conditions. After in vitro culture, EK 16-3 PME plantlets exhibited the highest dry weights among treatments. EK 16-3 PME and EK 16-3 PM had similarly high survivability, shoot and root dry weights and leaf lengths ex vitro compared to EK 16-3 control and EK 11-1 PM and PME plantlets. Ex vitro growth, survivability and P _n per leaf area of either genotype were not affected by CO₂ enrichment under modified photomixotrophic conditions. These results suggest that growth and survivability of sea oats genotypes with different acclimatization capacities can be enhanced by optimizing culture conditions.     

入侵植物猫爪藤体外细胞毒活性成分的筛选分离

为了筛选分离入侵植物猫爪藤的细胞毒活性成分,采用MTT法以75%乙醇提取物的不同组分分别处理人肝癌细胞SMMC7721、Bel7402和正常肝细胞Chang Liver,对他们的体外增殖抑制率进行了研究。结果表明,总醇提物的氯仿组分对肝癌细胞表现出明显的体外增殖抑制作用,其次是石油醚组分。从氯仿萃取组分中分离出具有更强细胞毒活性的成分熊果酸。因此,入侵植物猫爪藤具有体外细胞毒活性,熊果酸是其体外细胞毒活性的主要成分之一。     

细叶卷柏提取物的体外抗肿瘤活性

利用MTT法检测细叶卷柏乙酸乙酯和正丁醇提取物对HeLa细胞生长的抑制作用,利用流式细胞术(FCM)比较不同提取物对细胞凋亡的影响。结果显示:细叶卷柏的乙酸乙酯和正丁醇部位抑制细胞生长和诱导细胞凋亡作用均有明显的剂量依赖性。乙酸乙酯部位的IC50值为1.927μg/mL,正丁醇部位的IC50值为24.600μg/mL。因此,细叶卷柏乙酸乙酯部位的体外抗肿瘤活性相对较强,其次是其正丁醇部位,水提部位相对较弱。细叶卷柏是一种潜在的抗肿瘤药用植物。     

烟管头草的化学成分及其体外抗白血病活性研究

为研究烟管头草的化学成分及其对白血病细胞的体外抑制作用,该文采用硅胶柱层析、凝胶柱层析、大孔吸附树脂等方法对烟管头草(Carpesium cernuum)乙酸乙酯部位进行分离纯化,并运用¹H NMR、¹³C NMR和MS等波谱技术对化合物进行结构鉴定,采用MTT法测定化合物1-10对白血病细胞(K562、HEL)的体外抑制作用。结果表明:(1)从烟管头草乙酸乙酯部位共分离鉴定了11个化合物,分别为2, 9-epoxy-5, 9-dihydroxy-8-angeloyloxy-11-methoxymethyl-4(15)-germacraen-6, 12-olide(1)、cardivin D(2)、cernuumolide I(3)、cernuumolide J(4)、8-hydroxy-9, 10-diisobutyryloxythymol(5)、(2E, 6Z, 10E, 12R)-7-[(acetyloxy)methyl]-3, 11, 15-trimethylhexadeca-2, 6, 10, 14-tetraene-1, 12-diol(6)、9, 10-dihydroxyoctadecanoate(7)、1, 6-dihydroxy-8-hydroxymethyl-anthraquinone(8)、emodin(9)、4-megastigmen-3, 9-dione(10)、β-谷甾醇(11)。其中化合物1为新化合物,化合物5、7-10均为首次从天名精属中分离得到,化合物2、5-10均为首次从烟管头草中分离得到。(2)活性测试结果表明化合物cardivin D(2)、cernuumolide I(3)和cernuumolide J(4)对白血病细胞具有较好的体外抑制作用,其中对K562细胞的IC₅₀值分别为(2.27±0.46)、(5.53±0.41)、(3.90±0.80)μmol·L^-1,对HEL细胞的IC₅₀值分别为(1.84±0.14)、(2.36±0.90)、(2.31±1.17)μmol·L^-1。该研究结果丰富了烟管头草的化学成分,为抗白血病药物的研发提供了物质基础。     

酸枣果提取物在体内外对抗生素的增效作用及机制研究

作者研究团队先前从酸枣果的氯仿提取物中精制得到其低极性范围的活性组合物Fr.2a,发现Fr.2a与多种抗生素联用显示出广泛的协同抗菌作用。该研究在Fr.2a的基础上利用硅胶柱层析对酸枣果氯仿提取物中其他极性范围内的活性成分进行了分离纯化,得到精制物Fr.B,并对精制物Fr.B进行GC MS、核磁共振氢谱、红外光谱分析,以确定Fr.B的组成成分;通过抗菌谱分析和细胞通透性分析,以明确Fr.B的抗菌增效谱和抗菌增效机制;采用熔和法将精制物Fr.B制备成软膏,通过小鼠伤口感染模型评价该软膏对抗生素的增效效果。结果表明：(1)由酸枣果氯仿提取物进一步精制得到的Fr.B组分,主要包含反油酸、油酸、顺 10 十六碳烯醇、棕榈酸等脂肪酸类化合物。(2)Fr.B分别与庆大霉素、妥布霉素、氨苄青霉素、氯霉素、红霉素、夫西地酸、制霉菌素、酮康唑和两性霉素B等多种抗生素联用时显示出广泛的协同抗菌作用。(3)Fr.B可破坏细胞膜和细胞壁的完整性而增强细菌细胞的通透性。(4)在体内和体外Fr.B均能显著增强红霉素对耐甲氧西林金黄色葡萄球菌(MRSA)的杀菌作用,从而提高红霉素对MRSA菌株引起的伤口感染的治疗效果。研究表明,本研究所得到的Fr.B具有广谱的抗菌增效活性,能够增强红霉素对伤口耐药菌感染的治疗效果。该研究结果为克服微生物对抗生素的耐药性提供了新的思路和解决方案。     

蒲公英糖蛋白体内外抗氧化作用研究

为了探讨蒲公英糖蛋白(TMGP)体内外抗氧化活性,采用H2O2、Fe2+、DPPH.和总抗氧化能力反应体系,检测蒲公英糖蛋白体外抗氧化活性,并与VC进行比较;同时建立D-半乳糖所致衰老小鼠模型,测定并比较TMGP组与模型组的血清、肝脏和脑内MDA含量和SOD、CAT、GSH-Px活性。结果显示:(1)随着TMGP浓度增加,其Fe2+、H2O2和DPPH.清除率均有所增加,当TMGP浓度为1.72mg/mL时,对H2O2、Fe2+清除率分别达到76.8%和55%,接近VC水平;当TMGP浓度为1.5mg/mL时,对DPPH.的清除率达到77%,也与VC水平相当,说明TMGP具有一定的体外总体抗氧化能力。(2)将TMGP按低、中、高剂量分别给小白鼠灌胃,可显著增强小鼠体内血清、肝脏、脑组织中SOD、CAT、GSH-Px活性,降低MDA含量,从而提高衰老小白鼠体内的抗氧化能力。研究表明,TMGP具有明显的体内外抗氧化作用。     

油莎豆快速繁殖体系的研究

为建立油莎豆(Cyperus esculentus)的快繁体系,以茎尖为外植体,MS为基本培养基,采用正交设计法研究了6-BA、KT和NAA组合对丛生芽增殖和生根的影响。结果表明,3种生长调节剂对油莎豆丛生芽增殖的影响为6-BA NAA KT,最佳生长调节剂组合为1.0 mg L~(-1) 6-BA+0.2 mg L~(-1) KT,培养4周的增殖系数为7.58。MS培养基为最优生根培养基,生根率可达88.10%,平均生根数为2.04条。这为高效繁育油莎豆优质种苗和种质资源优化奠定基础。     

Potential of Ginkgo biloba L. leaves in the management of hyperglycemia and hypertension using in vitro models

Leaves from four different Ginkgo biloba L. trees (1 and 2 – females; 3 and 4 – males), grown at the same conditions, were collected during a period of 5 months (from June to October, 2007). Water and 12% ethanol extracts were analyzed for total phenolics content, antioxidant activity, phenolic profile, and the potential in vitro inhibitory effects on α-amylase, α-glucosidase, and Angiotensin I-Converting Enzyme (ACE) enzymes related to the management of diabetes and hypertension. The results indicated a significant difference among the trees in all functional benefits evaluated in the leaf extracts and also found important seasonal variation related to the same functional parameters. In general, the aqueous extracts had higher total phenolic content than the ethanolic extracts. Also, no correlation was found between total phenolics and antioxidant activity. In relation to the ACE inhibition, only ethanolic extracts had inhibitory activity.     

Early markers of in vitro microspore reprogramming to embryogenesis in olive (Olea europaea L.)

Microspore embryogenesis to form haploid and double-haploid embryos and regenerated plants is an efficient method of producing homozygous lines for crop breeding. In trees, the process is of special interest since classical methods are impractical in many cases, as in Olea europaea L. Recently, a convenient method has been developed for microspore embryogenesis induction by stress in olive isolated microspores in vitro cultures. In the present work, the switch of the microspore developmental pathway and the formation of microspore-derived multicellular proembryos have been achieved and a cytochemical and immunocytochemical analysis was performed in the early stages. The young microspore proembryos displayed defined features different to both, the in vivo gametophytic, and the in vitro non-responsive microspores. Reprogrammed microspores showed an absence of starch, the occurrence of a first symmetrical division and cytokinesis, the presence of an abundant ribosomal population, and changes in cellulosic and pectic cell wall components which constituted early markers of the embryogenic microspore process. They provided new insights on the molecular and cellular events associated with the microspore reprogramming of woody plants, and specifically in olive, providing interesting knowledge which could guide future selection and regeneration strategies in this fruit tree of high economic interest.     

宽叶金粟兰的化学成分及其抗肿瘤活性研究

为探寻宽叶金粟兰(Chloranthus henryi)的化学成分及抗肿瘤活性,该研究采用硅胶柱层析、反相柱色谱、Sephadex LH-20凝胶和半制备高效液相等色谱技术对宽叶金粟兰95%乙醇提取物的乙酸乙酯部位进行分离纯化,根据理化性质与波谱数据并结合 参考文献鉴定所得化合物的结构,并采用MTT法评价化合物细胞毒活性。结果表明:(1)从该植物的95%乙醇提取物的乙酸乙酯部位分离并鉴定了12个化合物,分别为pipercyclobutanamide C(1)、chololactone A(2)、sarcanolide B(3)、环银线草醇A(4)、chloramultiol D(5)、chlorasessilifol B(6)、chlorajaponol(7)、tianmushanol(8)、spicachlorantins B(9)、spicachlorantins A(10)、及已灵素A(11)、chloramultiols A(12)。化合物1为新化合物,除化合物8外,其余化合物均为首次从宽叶金粟兰中分离得到。(2)细胞毒活性测试结果显示,仅化合物2和化合物7对人宫颈癌细胞HeLa有抑制作用,IC₅₀值分别为(4.50±0.27)μmol·L^-1和(4.25±0.08)μmol·L^-1,其他化合物对其均无抑制作用。该研究结果为进一步深度研究与开发利用金粟兰属草本植物提供了一定的科学依据。     

冷杉侧耳多糖提取工艺优化及体外抗氧化活性

【背景】冷杉侧耳（Pleurotus abieticola）是一种新型食药用真菌,具有潜在的经济价值。【目的】更好地开发利用冷杉侧耳中的多糖成分,挖掘潜在的功能性食品。【方法】采用响应面分析法对冷杉侧耳多糖的提取工艺进行优化,并通过设置不同浓度梯度的多糖和Vc （阳性对照）考察该多糖的1,1-二苯基-2-苦基肼自由基（1,1-diphenyl-2-picrylhydrazyl free radical,DPPH）、2,2''-联氮-双-3-乙基苯并噻唑林-6-磺硫（2,2''-azinobis-3-ethylbenzthiazoline-6-sulphonate,ABTS）和羟基自由基（hydroxyl radical,·OH）的清除能力及铁离子还原能力来评价冷杉侧耳多糖的体外抗氧化活性。【结果】最佳提取工艺：提取时间122.62 min,提取温度60.27℃,液料比28.87：1（体积质量比）,在该条件下,冷杉侧耳纯多糖提取率达到极大值2.39%。该多糖在浓度为1 mg/mL时,DPPH自由基清除率为49.42%,ABTS自由基清除率为88.37%,羟基自由基清除率为19.87%,铁离子还原力为0.273。【结论】本研究为更高效地开发与利用冷杉侧耳多糖提供了理论依据,为进一步挖掘其生物活性及多糖产品打下了基础。     

从肿瘤病人少量外周血淋巴细胞克隆抗体基因

建立杂交瘤单抗亲和层析纯化抗原、体外抗原致敏淋巴细胞和RT-PCR克隆人抗体基因的技术.将亲和层析纯化的大肠癌相关抗原CA-Hb3经SDS-PAGE和免疫印迹鉴定后,与IL-2和丝裂原于体外致敏大肠癌病人10 ml外周血淋巴细胞(PBL),出现淋巴母细胞化和集落形成现象.致敏PBL的总RNA比未致敏PBL的量增加了2.5倍.致敏后RT-PCR扩增的人抗体VH-CH1(IgG)和VL-CL(κ)基因的量比未致敏者多1.3倍.该技术可将鼠源杂交瘤单抗人源化.     

肺成体干细胞体外培养模型的研究进展北大核心CSCD

目前,肺体外培养模型有肺类器官和肺芯片两种主要手段。肺类器官是离体的肺上皮干细胞在体外特定的三维培养环境中生长,自发形成具有自我更新能力的干细胞簇并成功分化出功能细胞。肺芯片是利用人工活性膜为细胞提供组织分层结构,模拟微环境和机械力的仿生微流体芯片。由于原有二维培养模式缺乏精确的微结构和功能,组织体外培养模型作为模拟肺部发育、稳态、损伤和再生机制的研究工具,为肺部纤维化、癌症等疾病的探索提供了新的手段和可能。本文就肺成体干细胞两种体外培养模型的分类、研发历史、建立方法、实际应用、优缺点等方面进行综述,期望为器官移植和再生、药物筛选等应用提供参考。     

光质对白芨组培苗生理特性及酶基因表达的影响

为探讨光质对白芨(Bletilla striata)组培苗生长发育的影响,对不同光质下白芨组培苗的生长特征、抗氧化酶活性以及酶基因表达进行了研究。结果表明,蓝光和红光对白芨生长有显著促进作用,绿光的作用不明显。除了CAT外,不同光质处理白芨的APX、POD、SOD活性均呈上升趋势,且黄光处理的白芨SOD和APX活性最高,红光处理的POD活性最高,绿光处理的抗氧化酶活性比其他光质的低,蓝光处理35~45 d对抗氧化酶基因表达具有促进作用。因此,红光和黄光促进白芨生根组培苗的长高和生根;不同光质处理总体上提高了白芨氧化酶活性;白芨抗氧化酶基因的表达在蓝光处理下最大。