枇杷叶膏中齐墩果酸和熊果酸的含量测定

目的:建立枇杷叶膏中齐墩果酸和熊果酸的反相高效液相色谱测定方法。方法:色谱柱:Agela venusil XBP-C18(250mm×4.6 mm,5μm);流动相:甲醇-0.05 mol/L醋酸铵溶液(88∶12);流速为0.8 mL/min;检测波长为215 nm;柱温25℃。结果:齐墩果酸在2.6~26μg范围内与峰面积有良好的线性关系r,=0.999 1;熊果酸在0.825~8.24μg范围内与峰面积有良好的线性关系r,=0.999 5;平均回收率分别为99.53%和99.37%,RSD分别为0.28%和0.53%。结论:所用方法简单快速,专属性强,重现性好,可用于枇杷叶膏中齐墩果酸与熊果酸的含量测定。     

高效液相色谱法测定青叶胆片中齐墩果酸含量

目的：建立青叶胆片中齐墩果酸的含量测定方法。方法：采用高效液相色谱（HPLC）法,Sapphire C18柱（200 mm×4.6 mm,5μm）;流动相：甲醇-0.2%冰醋酸溶液（85∶15）;检测波长：210 nm;柱温：30℃。结果：齐墩果酸进样量线性范围为46～230 ng,y=5487x＋39280,R2=0.9991,平均加样回收率为100.00%,RSD为1.24%（n=6）。结论：HPLC法简单可行、结果可靠,可用于定量控制青叶胆片的质量。     

反相高效液相色谱法测定治咳枇杷露中乌索酸的含量

建立了反相高效液相色谱法测定枇杷露中乌索酸的含量,同时采用光电二极管阵列检测器检测乌索酸色谱峰的纯度。色谱柱为Nova-Pak C18(3.9×150 mm,4μm),流动相为甲醇-水(88∶12),流速1.0 mL/m in,检测波长210 nm,柱温25℃。乌索酸在0.039 5~0.237μg范围内线性关系良好(r=0.999 1),检出限为0.2 mg/L(3σ),平均回收率为98.7%。该法适于对含有乌索酸的药物进行质量评价。     

湘西桐叶药材熊果酸及齐墩果酸的HPLC法测定

建立一种高效、准确、稳定的桐叶熊果酸和齐墩果酸测定方法,测定湖南省湘西地区桐叶药材中熊果酸和齐墩果酸含量.采用高效液相色谱（HPLC）法,色谱条件依次为,色谱柱：TADE-PAKAF-C18柱（250 mm×4.6 mm,5 μm）;流动相：乙腈-甲醇-0.5%醋酸铵溶液（体积比61∶18∶21）;流速：1 mL/min;检测波长：210 nm;柱温：35 ℃;进样量：10 μL.结果表明：齐墩果酸与熊果酸分离度为1.73,均符合要求;熊果酸和齐墩果酸对照品分别在0.497 6～9.952 0 μg/mL和0.126 1～2.523 0 μg/mL范围内线性关系良好（r均为0.999 9）;熊果酸、齐墩果酸平均加样回收率分别为99.93%,98.97%;湘西产桐叶含熊果酸4.54～7.07 mg/g,含齐墩果酸2.50～3.20 mg/g.HPLC法分离效果好、灵敏度高、准确度高,是检测桐叶中熊果酸、齐墩果酸含量的科学有效手段.     

RP-HPLC法测定苦丁茶中熊果酸和齐墩果酸的含量

研究建立反相高效液相色谱法测定苦丁茶中熊果酸和齐墩果酸的含量。采用甲醇溶剂超声提取法,色谱条件:EclipseXDB-C18柱(5μm,4.6×150mm)、流动相为甲醇-0.2%磷酸水溶液(88:12)、检测波长为220nm、流速为0.8ml/min、柱温为35℃、进样量20μl。在此色谱条件下,熊果酸和齐墩果酸与其它成分达到了基线分离,且分别在0.204～2.04μg、0.0717～1.342μg范围内,进样量与峰面积呈良好的线性关系,二者加标回收率分别为97.65%、97.42%,RSD分别为1.96%、1.5%。本方法简便,灵敏,重现性好,结果准确可靠。     

高效液相色谱法同时测定罗布麻浸膏粉中金丝桃苷、异槲皮苷、槲皮素的含量

采用HPLC法同时测定罗布麻浸膏粉中金丝桃苷、异槲皮苷、槲皮素的含量.色谱柱为YMC-Pack C18(250×4.6 mm),流动相为乙腈-甲醇(10∶1)和0.4%磷酸,梯度洗脱;二极管阵列检测器:检测波长360 nm;分别以金丝桃苷、异槲皮苷、槲皮素对照品为外标,用标准曲线法进行定量.在0.25~10μg/mL的范围内,金丝桃苷、异槲皮苷、槲皮素的浓度与吸收峰面积之间线性关系良好,相关系数分别为r金丝桃苷=0.999 4、r异槲皮苷=0.999 5、r槲皮素=0.999 6,回收率在85.57%~99.96%之间(RSD小于4.45%).     

高效液相色谱法测定三叶香茶菜中齐墩果酸含量

采用高效液相色谱(HPLC)法,选用大连依利特Hypersil ODS2色谱柱,流动相甲醇-0.1%磷酸溶液(80:20),检测波长207nm,柱温22℃,测定广西三叶香茶菜中的齐墩果酸含量.结果表明,齐墩果酸在0.175～7μg之间呈线性关系,齐墩果酸平均回收率为98.91%,RSD为1.886%.该方法准确可行,重复性好,可以作为测定三叶香茶菜中齐墩果酸含量的方法.     

毛细管气相色谱法测定苯甲酰氯的含量

建立了毛细管气相色谱内标法测定苯甲酰氯的含量测定方法,用HP-5(30m×0.32mm×0.25μm)毛细管气相色谱柱,FID检测器,三氯甲烷为溶剂,以正十一烷为内标进行气相色谱测定.苯甲酰氯在0.25324-0.42285μg/μL(r=0.9999)范围内呈良好线性关系;平均回收率为99.75%,RSD为1.28%.     

复方肝舒丸的质量标准研究

目的:建立复方肝舒丸的质量标准.方法:采用薄层色谱法对丸剂中的丹参、大黄、当归、白术进行定性鉴别.采用高效液相色谱(HPLC)法测定丸剂所含丹参酮ⅡA的量,色谱柱为Welchrom-C18柱(5μm,250 mm×4.6mm),流动相为甲醇-水(体积比80∶20),流速1.0 m L·min-1,柱温30℃,检测波长为270 nm.采用HPLC法测定大黄素、大黄酚的含量,色谱柱为Welchrom-C18柱(5μm,250 mm×4.6 mm),流动相为甲醇-0.1%磷酸溶液(体积比90∶10),柱温25℃,流速1.0 m L·min-1,检测波长为254 nm.结果:薄层斑点清晰,阴性对照无干扰,专属性强.丹参酮ⅡA在0.02~0.2μg范围内线性关系良好(r=0.9999),平均加样回收率为99.26%,RSD为0.66%(n=9).大黄酚在0.2~2.0μg范围内线性关系良好(r=0.9999),平均加样回收率为99.21%、RSD为0.72%(n=9).大黄素在0.2~2.0μg范围内线性关系良好(r=0.9999),平均加样回收率为99.21%,RSD分别0.61%(n=9).结论:本方法操作简单、灵敏度高、结果准确、重现性好、专属性强,可作为复方肝舒丸的质量控制标准.     

橘核中柠檬苦素的提取与含量测定

建立了高效液相色谱测定橘核中柠檬苦素含量的方法。采用超声法从橘核中提取柠檬苦素,以Agilent Eclipse XDB-C18柱(250 mm×4.6 mm,5μm)为分析柱,乙腈—水(65∶35,v/v)溶液为流动相,用紫外检测器在波长210 nm处进行测定。结果表明,柠檬苦素的质量浓度在(20～160)μg/mL范围内与峰面积呈良好的线性关系,相关系数r=0.999 9。方法的平均加样回收率为101.5%,RSD=1.37%(n=6)。该法简便、准确、可靠,能为橘核中柠檬苦素的测定及开发利用提供参考。     

不同生境拟穴青蟹螯足肌肉营养品质评价

为探究不同生境、不同食物源拟穴青蟹(Scylla paramamosain，以下简称“青蟹”)的螯足肌肉营养品质的差异，本研究通过采集5种不同生境青蟹(生态青蟹、藤壶青蟹、天然青蟹、混饵养殖青蟹和单饵养殖青蟹)，取其螯足肌肉组织测定基本营养成分、氨基酸含量和脂肪酸含量，并通过必需氨基酸指数(EAAI)、支链氨基酸与芳香族氨基酸含量的比值(F)进行分析。结果表明，生态青蟹的蛋白质含量略高于天然青蟹和混饵养殖青蟹；藤壶青蟹的含水率最高，蛋白质含量最低；5种青蟹的粗脂肪和总灰分含量差异均不显著。生态青蟹的总氨基酸含量和必需氨基酸含量均最高，藤壶青蟹的鲜味氨基酸含量最高；藤壶青蟹的EAAI (112.48)和F (2.36)最高，生态青蟹的EAAI (95.35)和F (1.95)分别与天然青蟹的EAAI (96.15)和F (1.90)基本一致；单饵养殖青蟹的EAAI (72.00)和F (1.53)均最低。生态青蟹的单不饱和脂肪酸、多不饱和脂肪酸含量最高，其二十二碳五烯酸+二十二碳六烯酸(EPA+DHA)显著高于天然青蟹，且部分不饱和脂肪酸含量显著高于天然青蟹、混饵养殖青蟹和单饵养殖青蟹。从蛋白质、总氨基酸、必需氨基酸和不饱和脂肪酸的含量来看，生态青蟹的含量最高；从EAAI和F来看，藤壶青蟹的评价最高，说明2种红树林生态修复产出的青蟹品质较好。     

A preliminary study of crassulacean acid metabolism (CAM) in the endangered aquatic quillwortIsoetes sinensis Palmer in China

Isoetes sinensis Palmer (Isoetaceae) is an aquatic or amphibious plant that is critically endangered in China. Previous studies have revealed the crassulacean acid metabolism (CAM)-like photosynthetic pathway occurs commonly in submerged leaves in genusIsoetes. Water chemistry parameters and the titratable acidity content of the plant extract were measured from samples obtained in the early morning (7∶00) and late afternoon (15∶00) from twoI. sinensis populations in China. One population occurs in the eulittoral zone of a freshwater tidal river at low elevation (134 m) and another occurs in a densely vegetated, high elevation (1 100 m) alpine shallow pool. Significant differences in pH and titratable acidity of the plant extract were detected between the morning and afternoon samples. These changes are associated with diurnal changes in water chemistry. Our results provide the first evidence for the existence of the CAM pathway in the East Asian endemicIsoetes sinensis Palmer. The magnitude of fluctuations in the titratable acidity of the plant extract may be correlated with the severe carbon limitation imposed on the plants by its aquatic habitat. Foundation item: Supported by the State Key Basic Research and Development Plan (G2000046805) Biography:Pang Xin-an (1974-), male, Master candidate, research direction: conservation biology.     

一株高产乳酸鼠李糖乳杆菌的选育

采用紫外线和Co60照射联合诱变鼠李糖乳杆菌(Lactobacillus rhamnosus)JCM1553菌株,选育得到1株L-乳酸高产突变株SCT-10-10-60.经77代传代培养证实该菌株L-乳酸发酵遗传稳定.在37℃,200rpm下,该菌株摇瓶发酵葡萄糖60h的发酵液乳酸浓度达到最大,为195.67g/L,发酵糖酸转化率达到95.33％,比出发菌株最大乳酸产量、发酵速率和糖酸转化率分别提高了16.24％、50.13％和17.81％.相同条件下该菌株发酵木薯淀粉84h的乳酸浓度达到最大值,为203.33g/L,糖酸转化率达到78.85％,比出发菌株最大乳酸产量和发酵速率均提高了29.49％,糖酸转化率则提高24.53％.该菌株发酵产物的L-乳酸含量高达96.75％,与出发菌株(96.97％)无统计学显著差异(P＞0.05).该高产菌株乳酸发酵性能提高的主要原因是菌体增长速率加快.其L-乳酸发酵性能显著优于现有的生产菌株,具有较高的潜在工业价值.     

Genome-wide distribution of histone H3 acetylation in all- trans retinoic acid induced neuronal differentiation of SH-SY5Y cells

With chromatin immunoprecipitation (ChIP) and promoter DNA microarray analyses (ChIP-on-chip), we analyzed the variations of acetylation on histone H3 in all-trans retinoic acid (RA) induced neuronal cell differentiation. Neuroblastoma SH-SY5Y cells were treated with RA for 24 h and the acetylation on histone H3 in the promoter region of the genes was detected. Results showed that, after treatment, the level of acetylation on histone H3 elevated in 597 genes in the genome, and reduced in the other 647 genes compared with those of the control. In summary, we have successfully adopted a high throughput technique to detect and analyze variations of acetylation of histone H3 in human genome at the early phage of RA induced neuronal differentiation of the SH-SY5Y cells. Supported by National Natural Science Foundation of China (Grant Nos. 90408007 and 30721063) and National Key Basic Research and Development Program of China (Grant No. 2004CB518605)     

广东石豆兰及其易混伪品的营养成分分析与评价

为探究广东石豆兰(Bulbophyllum kwangtungense)、密花石豆兰(B.odoratissimum)和云南石仙桃(Pholidota yunnanensis)的营养成分差异,为植物资源的开发利用提供理论依据,本研究以3种兰科植物的全株为材料,按照国家标准中的检测方法对其主要营养成分、活性物质及矿物质元素进行测定,并通过氨基酸评分(AAS)和化学评分(CS)对其氨基酸营养价值进行评价。结果表明,广东石豆兰中粗蛋白、灰分、总糖、硒、钙的含量与密花石豆兰及云南石仙桃无显著差异(P＞0.05),而维生素E、钾含量显著高于密花石豆兰及云南石仙桃(P＜0.05)。广东石豆兰和密花石豆兰中茶多酚、镁含量显著高于云南石仙桃(P＜0.05);广东石豆兰和云南石仙桃中氨基酸总量、必需氨基酸总量、鲜味氨基酸、药效氨基酸和总黄酮含量显著高于密花石豆兰,而粗脂肪含量显著低于密花石豆兰(P＜0.05)。密花石豆兰和云南石仙桃作为广东石豆兰的易混伪品,在预防高血压和心血管疾病以及抗肿瘤活性、抗宫颈癌、延缓衰老、增强活力等营养保健功效上,密花石豆兰及云南石仙桃都不能完全替代广东石豆兰。     

Induction of cranial and posterior trunk neural crest by exogenous retinoic acid in zebrafish

Retinoic acid (RA) plays an important role in development of vertebrate embryos. We demonstrate impacts of exogenous RA on the formation of neural crest cells in zebrafish using specific neural crest markers sox9b and crestin. Treatment with all -trans RA at 10₋₇ mmol/L at 50% epiboly induces sox9b expression in the forebrain and crestin expression in the forebrain and midbrain, resulting in significant increase of pigment cells in the head derived from the cranial neural crest. In addition, RA treatment induces expression of sox9b and crestin in the caudal marginal cells of the neuroectoderm during early segmentation. Earlier commitment of these cells to the neural crest fate in the posterior margins leads to abnormal development of the posterior body, probably by preventing mingling of ventral derived and dorsal-derived cells during the formation of the tailbud.     

Surface Dissociation Properties of Short Chain Carboxyl Mercaptan Self-Assembled Monolayers by Impedance Titration

Impedance titration was used to determine the surface dissociation characteristics of short-chain carboxyl mercaptan self-assembled monolayers （SAMs）. Based on the change of the cyclic voltammetric peak current and the charge-transfer resistance, which was related to pH value of the solution, the surface pKa of mercaptoacetic acid（MA）, 3-mercaptopropionic acid（MPA） and ω-mercaptohexanic acid（MHA） self-assembled membranes, with ionic strength being 0.1 mol/L, were determined to be 5.20, 4.80, 7.40, respectively. In addition, factors such as time needed for assembling, structure of monolayers and ionic strength, which effected the surface pKa, were studied as well. Such surface pKa shifts were sufficiently explained by interactions between interfacial molecules and hydrophobicity.     

猪粪废水用于三角褐指藻培养的研究

研究了以猪粪废水培养一株三角褐指藻(Phaeodactylum tricornutum)的可行性.结果表明:猪粪废水经30g/L盐水适当稀释后可直接用于三角褐指藻的培养,无需添加其他营养物质.在污水稀释率为25倍时,藻细胞可良好地生长,最高密度为合成培养基的1.52倍.同时三角褐指藻有效去除了污水中的氮磷,总氮、氨氮和总磷的去除率分别为23%,93%和93%.与合成培养基养殖的藻相比,猪粪废水养殖的三角褐指藻的二十碳五烯酸和多不饱和脂肪酸的含量略有上升,实现了培养三角褐指藻转化废水为生物量并积累多不饱和脂肪酸的资源化.     

β-Glucosidase treatment and infestation by the rice brown planthopper Nilaparvata lugens elicit similar signaling pathways in rice plants

β-Glucosidase has been reported to induce the production of herbivore-induced plant volatiles. However, how it works remains unclear. Here, we investigated the levels of salicylic acid （SA）, jasmonic acid （JA）, ethylene, and H2O2, all of which are known signaling molecules that play important roles in induced plant defense in rice plants treated with β-glucosidase, and compared these to levels in plants infested by the rice brown planthopper Nilaparvata lugens （Stal）. Results showed that wounding and treatment by β-glucosidase increased the levels of SA, ethylene, and H2O2, but not JA, in all plants compared to control plants. The signaling pathways activated by β-glucosidase treatment are similar to those activated by an infestation by N. lugens, although the magnitude and timing of the signals elicited by the two treatments are different. This may explain why both treatments have similar volatile profiles and are equally attractive to the parasitoid Anagrus nilaparvatae Pang et Wang.