Characteristics of the microzooplankton community in Jiaozhou Bay, Qingdao, China

The species composition and abundance of microzooplankton at 10 marine and five coastal stations (Hongdao, Daguhe, Haibohe, Huangdao and Hangxiao) in the Jiaozhou Bay (Qingdao, China) were studied in 2001. The microzooplankton community was found to be dominated by Tintinnopsis beroidea, Tintinnopsis urnula, Tintinnopsis brevicollis and Cvdonellopsis sp. The average abundance of microzooplankton was highly variable among stations. Specifically, the abundance of microzooplankton was higher at inshore stations and lower in the center of the bay (St. 5), bay mouth (St. 9) and outside the bay (St. 10). The highest average annual densities (346 ind./L) was observed at St. 3, while the lowest (55 ind./L) was at St. 10. Two abundance peaks were recorded in May (324 ind./L) and February (300 ind./L). The distribution of microzooplankton in three sampling layers at the 10 stations was relatively homogenous and the abundance decreased slightly as the water depth increased. At coastal stations, the highest average annual density was recorded at Hongdao Station (677 ind./L), followed by Daguhe Station (616 ind./L), Haibohe Station (400 ind./L), Huangdao Station (275 ind./L) and Hangxiao Station (73 ind./L). Furthermore, a 24-h sampling analysis conducted at Hangxiao Station revealed that the microzooplankton assemblages were characterized by a bimodal diel vertical migration pattern, with the highest densities occurring at dusk (154 ind./L), followed by dawn (146 ind./L), noon (93 ind./L) and midnight (77 ind./L). The density of microzooplankton in the Jiaozhou Bay was in the middle range of the densities of temperate coastal waters worldwide.

Sesquiterpenes from the red alga Laurencia tristicha

Seven new sesquiterpenes (1-7), together with seven known sesquiterpenes, aplysin (8), aplysinol (9), gossonorol (10), 7,10-epoxy-ar-bisabol-11-ol (11), 10-epi-7,10-epoxy-ar-bisabol-11-ol (12), johnstonol (13), and laurebiphenyl (14), have been isolated from the red alga Laurencia tristicha. The structures of new compounds were established as laur-11-en-2,10-diol (1), laur-11-en-10-ol (2), laur-11-en-1,10-diol (3), 4-bromo-1,10-epoxylaur-11-ene (4), cyclolauren-2-ol (5), laurentristich-4-ol (6), and ar-bisabol-9-en-7,11-diol (7) by means of spectroscopic methods including IR, HRMS, and ID and 21) NMR techniques. Compound 6 possessed a novel rearranged skeleton. All compounds were tested against several human cancer cell lines including lung adenocarcinoma (A549), stomach cancer (BGC-823), hepatoma (Bel 7402), colon cancer (HCT-8), and HELA cell lines. Laurebiphenyl (14) showed moderate cytotoxicity against all tested cell lines, with IC50 values of 1.68, 1.22, 1.91, 1.77, and 1.61 mu g/mL, respectively. Other compounds were inactive (IC50 > 10 mu g/mL).

Flow cytometry and ultrastructure of cryopreserved red seabream (Pagrus major) sperm

The objectives were to assess motility, fertilizing capacity, structural integrity, and mitochondrial function in fresh versus frozen-thawed (15% DMSO was used as a cryoprotectant) sperm from red seabrearn (Pagrus major). Mean (+/- S.D.) rates of motility, fertilization and hatching of frozen-thawed sperm were 81.0 +/- 5.4, 92.8 +/- 1.9, and 91.8 +/- 5.2%, respectively; for fresh sperm, they were 87.5 +/- 7.7, 95.8 +/- 2.4, and 93.8 +/- 4.2%. Although motility was lower in frozen-thawed versus fresh sperm (P < 0.05), there was no effect (P > 0.05) of cryopreservation on fertilization or hatching. Based on scanning and transmission electron microscopy, 77.8 +/- 5.6% of fresh sperm had normal morphology, whereas for frozen-thawed sperm, 63.0 +/- 7.2% had normal morphology, 20.6 +/- 3.1% were slightly damaged (e.g. swelling or rupture of head, mid-piece and tail region as well as mitochondria), and 16.4 +/- 4.2% were severely damaged. Sperm were stained with propidium iodide and Rhodamine 123 to assess plasma membrane integrity and mitochondrial function, respectively, and examined with flow cytometry. For fresh sperm, 83.9% had an intact membrane and functional mitochondria, whereas for frozen-thawed sperm, 74.8% had an intact membrane and functional mitochondria, 12.7% had a damaged membrane, 9.9% had nonfunctional mitochondria, and 2.6% had both a damaged membrane and nonfunctional mitochondria. In conclusion, ultrastructure and flow cytometry were valuable for assessment of frozen-thawed sperm quality; cryopreservation damaged the sperm but fertilizing ability was not significantly decreased. (c) 2007 Elsevier Inc. All rights reserved.

青海歧穗大黄及其生长土壤中9种无机元素含量特征

为对比青海高原境内不同生境歧穗大黄中9种无机元素含量特征,用原子吸收光谱法分析了其宏量元素K、Na、Ca、Mg、P及微量元素Cu、Zn、Fe、Mn含量.结果表明,青海歧穗大黄植物与其土壤环境呈现出不同的无机元素含量特征,但一致表现为Ca和P在植物的富集,且植物中P含量随海拔升高而明显增加,Zn含量随海拔升高而增加.

Analysis for Flavonoids in Bee Pollens by Capillary Electrophoresis

A capillary electrophoresis (CE) method has been developed for the determination of six bioactive flavonoids that are commonly found in health foods: hesperidin, hyperin, isorhamnetin, kaempferol, quercetin and rutin. The effects of several parameters, such as pH, buffer concentration, separation voltage and UV detector wavelength, were investigated to find the optimal conditions. Using a HbBCh-NaiB-iO? buffer (pH 9.2), the analytes can be separated within 8 min. The relative standard deviations of migration times in eight injections were between 0.77% and 0.93%, and those of the peak areas ranged from 3.8% to 8.6%. A high reproducibility and excellent linearity was observed over two orders of magnitude, with detection limits (S/N = 3) ranging from 0.34ug ml to 2.9ug ml for all the six analytes. Recoveries ranged from 80.4 % to 113.9 %. The new method is simple, reproducible and sensitive. No solid phase extraction for sample pretreatment is necessary. Analysis results are accurate in application to bee pollens.

南门峡裂腹鱼亚科鱼类形态相似种的分类学地位——形态趋同进化实例

受高原抬升所致的水系变迁及人类活动的影响,分布于南门峡河流的裂腹鱼亚科鱼类与黄河干支流种群间的基因交流受到长期限制.作为孤立小群体,探讨其分类学地位及其在小生境中的进化机制对了解青藏高原鱼类多样性和物种的形成、进化具有重要意义.本文采用聚合酶链式反应(PCR)和直接测序方法获得了南门峡裂腹鱼亚科鱼类(n=29)及其近缘种(n=19)共48个个体的线粒体DNA(mtDNA)细胞色素b(cyt b)基因的全序列(1 140 bp),并以厚唇裸重鱼和尖裸鲤为外群构建了MP和Bayesian系统进化树.南门峡裂腹鱼亚科鱼类29个个体的序列经排序后,发现有100个(8.77%)多态性位点,共定义了16个单倍型,在系统进化树上分布于截然不同的两个族群中.其中5个单倍型(NMX3、6、7、13、15)与其近缘种花斑裸鲤和青海湖裸鲤形成单系群(MP 99%,Bayesian 98%),而其余11个单倍型(NMX1、2、4、5、8、9、10、11、12、14、16)与黄河干支流的黄河裸裂尻鱼形成另一个单系群(MP 99%,Bayesian 99%).序列差异分析显示,分布于不同族群的南门峡裂腹鱼亚科鱼类之间存在较大的碱基差异(平均为7.42%),显示出种间差异水平,表明分布于南门峡河流的裂腹鱼亚科鱼类可能是花斑裸鲤和黄河裸裂尻鱼形态相似种的复合体.结合青藏高原隆升所致的气候环境变化和高原北部水系变迁的事件,推断形态趋同进化可能导致了南门峡河流裂腹鱼亚科鱼类形态相似种的共存,而小生境自然选择压力是引发适应性形态趋同进化的主要原因.

荧光衍生试剂1-[2-（对甲苯磺酸醋）乙基]2-苯基咪唑[4,5-f]9,10-菲的合成及其在长链脂肪酸分析中的应用

合成了新的荧光衍生试剂1-[2-（对甲苯磺酸酯）乙基]-2-苯基咪唑[4,5-f]9,10-菲（TsEPIP），并将其作为柱前衍生化试剂，在Eclipse XDB-C：色谱柱上采用梯度洗脱实现了11种长链（C_(20)～C_(30)）游离脂肪酸（FFA）衍生物的基线分离。利用柱后在线的串联质谱并以大气压化学电离源（APCI）的正离子模式实现了各组分的质谱定性。对土壤及3种苔醉（东亚毛灰鲜、锦丝鲜、羽平鲜）中FFA组分的定量结果表明，苔鲜植物从土壤中富集了大量的长链游离脂肪酸。荧光检测的激发波长和发射波长分别为260 nm和380 nm。线性回归系数大于0.9996，检测限为26.19～76.67 fmol。所建立的方法具有良好的重现性，对实际样品的测定结果令人满意。

9种“藏茵陈”原植物中的7种有效化学成分研究

目的 研究藏药市场上9种“藏茵陈”植物中有效化学成分，根据所含成分的差异及其生理活性，确定这些植物的药用价值。方法 采用HPLC法测定7种成分的量。结果 9种植物的有效成分差异很大。结论 针对不同的化学成分用途，选择不同的植物，有效利用资源。[著者文摘]

青海青甘韭9个居群的核型

本文研究了青海葱属青甘韭 9个居群的染色体数目和核型。其中分布于湟源、西宁和共和海拔相对较低的地区的居群为 2倍体 ,核型公式为 2n =2x =16 =14m +2st (2SAT) (湟源居群和西宁居群 ) ,2n =2x =16 =12m +2sm +2st (2SAT) (共和居群 ) ;分布于玛沁、玉树、囊谦等高海拔地区的居群为 4倍体 ,核型公式为 2n =4x =32 =2 8m +4st (2SAT) (玉树居群 1和囊谦居群 1) ,2n =4x =32 =2 4m +4sm +4st (玛沁居群和玉树居群 3)和 2n =4x =32 =2 6m +2sm+4st (玉树居群 2 ) ;囊谦一个生长在林下的居群为8倍体，2n =8x =64 =54m +2sm +8st.讨论了居群间的核型分化和倍性与分布的关系。

高寒草甸牧草产量和草场载畜量模拟研究及对气候变暖的响应

高寒草甸地区温度是限制牧草地上年产量提高的主要因素。利用这一点, 引进牧草产量与生长期间的产量积温比概念, 建立高寒草甸牧草产量的估算模式。其估测值与实测值的拟合率较高, 相对误差平均只有2% , 说明模式的建立具有较好的应用价值。研究还表明, 现实状况下高寒草甸地区牲畜理论负载能力约为2. 54 个羊单位。在未来气候变暖(假设气温升高2 ℃, 降水不变) 的情景下, 草场生产力将有所降低, 相应的草场理论载畜量降低至1. 04 个羊单位。

青藏高原不同海拔矮嵩草蛋白质、脂肪和淀粉含量的变异

生长在青藏高原4 个不同海拔地区的矮嵩草(Kobresia humilis) , 其蛋白质、脂肪和碳水化合物的含量有明显差异。其中海拔最高的大坂山(4, 000m ) 植株中蛋白质含量平均比海拔依次较低的金羊岭(3, 800m ) , 海北站(3, 200m ) 和西宁地区(2, 200m ) 的分别高出9.9% ,17.3% 和39.4%; 脂肪含量平均分别高出7.1% , 77.8% 和106.0%; 淀粉含量也平均分别高出2.4% , 21.6% 和32.7%。同时表明, 海拔高度对上述若干生化成分含量的季节性动态变化均有明显的影响。从而显示, 高海拔地区的植物所以具有较强的抗寒性和适应逆境胁迫的能力, 是与体内蛋白质、脂肪和碳水化合物(淀粉) 的大量积累增加密切相关。

CE determination of 2-(9-carbazole)ethyl chloroformate-labeled oligopeptides

A pre-column derivatization method for sensitive determination of oligopeptides, using the tagging reagent 2-(9-carbazole)ethyl chloroformate (CEOC-Cl) followed by capillary electrophoresis (CE) with diode-array detection, has been developed. Maximum yield close to 100% were observed when a three to fourfold molar excess of reagent was used at pH 9.0-10.0. Excess reagent was extracted with n-hexane-ethyl acetate 9:1-10:1 (v/v); this enabled direct analysis using CE with no significant disturbance from the major fluorescent reagent degradation by-products. The effects on the results of buffer pH and of SDS and organic modifier concentrations were examined. Good baseline resolution in the separation of five CEOC-peptides was achieved with a 48.5-cm total length (effective length 40 cm) 50-mu m inner diameter capillary column.

Determination of amines using 2-(11H-benzo[a]carbazol-11-yl) ethyl chloroformate (BCEC-Cl) as labeling reagent by HPLC with fluorescence detection and identification with APCI/MS

A pre-column derivatization method for the sensitive determination of amines using a labeling reagent 2-(11H-benzo[a]-carbazol-11-yl) ethyl chloroformate (BCEC-Cl) followed by high-performance, liquid chromatography with fluorescence detection has been developed. Identification of derivatives was carried out by LC/APCI/MS in positive-ion mode. The chromophore of 1,2-benzo-3,4-dihydrocarbazole-9-ethyl chloroformate (BCEOC-Cl) reagent was replaced by 2-(11H-benzo[a]-carbazol-11-yl) ethyl functional group, which resulted in a sensitive fluorescence derivatizing reagent BCEC-Cl. BCEC-Cl could easily and quickly label amines. Derivatives were stable enough to be efficiently analyzed by HPLC and showed an intense protonated molecular ion corresponding m/z [M+ H](+) under APCI/MS in positive-ion mode. The collision-induced dissociation of the protonated molecular ion formed characteristic fragment ions at m/z 261.8 and m/z 243.8 corresponding to the cleavages of CH2O-CO and CH2-OCO bonds. Studies on derivatization demonstrated excellent derivative yields over the pH 9.0-10.0. Maximal yields close to 100% were observed with three- to four-fold molar reagent excess. In addition, the detection responses for BCEC-derivatives were compared to those obtained using 1,2-benzo-3,4-dihydrocarbazole-9-ethyl chloroformate (BCEOC-Cl) and 9-fluorenyl methylchloroformate, (FMOC-Cl) as labeling reagents. The ratios I-BCEC/I-BCEOC = 1.94-2.17 and I-BCEC/I-FMOC = 1.04-2.19 for fluorescent (FL) responses (here, I was relative fluorescence intensity). Separation of the derivatized amines had been optimized on reversed-phase Eclipse XDB-C-8 column. Detection limits calculated from 0.50 pmol injection, at a signal-to-noise ratio of 3, were 1.77-14.4 fmol. The relative standard deviations for within-day determination (n = 11) were 1.84-2.89% for the tested amines. The mean intra- and inter-assay precision for all amines levels were < 3.64% and 2.52%, respectively. The mean recoveries ranged from 96.6% to 107.1% with their standard deviations in the range of 0.8-2.7. Excellent linear responses were observed with coefficients of > 0.9996. (C) 2006 Elsevier B.V. All rights reserved.

Pre-column derivatization of amines with 1,2-benzo-3,4-dihydrocarbazole-9-isopropyl chloroformate followed by LC-fluorescence and LC-APCI-MS

A pre-column derivatization method for the sensitive determination of amines using the labeling reagent 1,2-benzo-3,4-dihydrocarbazole-9-isopropyl chloroformate (BCIC-Cl) followed by high-performance liquid chromatography with fluorescence detection has been developed. Identification of derivatives is carried out by high performance liquid chromatography/atmospheric pressure chemical ionization (LC-APCl-MS-MS). The chromophore of 2-(9-carbazole)-ethyl chloroformate (CEOC) reagent is replaced by 1,2-benzo-3,4-dihydrocarbazole-9-isopropyl functional group, which results in a sensitive fluorescence derivatizing reagent BCIC-Cl. BCIC-Cl can easily and quickly label amines. Derivatives are stable enough to be efficiently analyzed by high-performance liquid chromatography and show an intense protonated molecular ion corresponding m/z [MH](+) under APCl in positive-ion mode. The collision-induced dissociation of protonated molecular ion formed a product at m/z 260 corresponding to the cleavage of CH2-OCO bond. Studies on derivatization demonstrate excellent derivative yields over the pH 9.0-10.0. Maximal yields close to 100% are observed with a 3 to 4-fold molar reagent excess. In addition, the detection responses for BCIC derivatives are compared with those obtained using CEOC and FMOC as derivatization reagents. The ratios of l(BCIC)/l(CEOC) and l(BCIC)/l(FMOC) are, respectively, 1.23-3.14 and 1.25-3.08 for fluorescent (FL) responses (here, l is relative fluorescence intensity). Separation of the derivatized amines had been optimized on reversed-phase Eclipse XDB-C-8 column. Detection limits are calculated from 1.0 pmol injection, at a signal-to-noise ratio of 3, are 10.6-37.8 fmol. The mean interday accuracy ranges from 94 to 105% for fluorescence detection with the largest mean %CV < 7.5. The mean interday precision for all standards is < 6.0% of the expected concentration. Excellent linear responses are observed with coefficients of > 0.9997.

2-(2-Phenyl-1H-phenanthro-[9,10-d]imidazole-1-yl)-acetic acid (PPIA) and its application for determination of amines by high performance liquid chromatography with fluorescence detection and identification with mass spectroscopy/atmospheric pressure chemical ionization

A simple, sensitive, and mild method for the determination of amino compounds based on a condensation reaction with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride (EDC-HCI) as the dehydrant with fluorescence detection has been developed. Amines were derivatized to their acidamides with labeling reagent 2-(2-phenyl-1H-phenanthro-[9,10-d]imidazole-1-yl)-acetic acid (PPIA). Studies on derivatization conditions indicated that the coupling reaction proceeded rapidly and smoothly in the presence of a base catalyst in acetonitrile to give the corresponding sensitively fluorescent derivatives with an excitation maximum at lambda(ex) 260nm and an emission maximum at lambda(em) 380nm. The labeled derivatives exhibited high stability and were enough to be efficiently analyzed by high-performance liquid chromatography. Identification of derivatives was carried out by online post-column mass spectrometry (LC/APCI-MS/MS) and showed an intense protonated molecular ion corresponding m/z [MH](+) under APCI in positive-ion mode. At the same time, the fluorescence properties of derivatives in various solvents or at different temperature were investigated. The method, in conjunction with a gradient elution, offered a baseline resolution of the common amine derivatives on a reversed-phase Eclipse XDB-C-8 column. LC separation for the derivatized amines showed good reproducibility with acetonitrile-water as mobile phase. Detection limits calculated from 0.78 pmol injection, at a signal-to-noise ratio of 3, were 3.1-18.2 fmol. The mean intra- and inter-assay precision for all amine levels were < 3.85% and 2.11%, respectively. Excellent linear responses were observed with coefficients of > 0.9996. The established method for the determination of aliphatic amines from real wastewater and biological samples was satisfactory. (c) 2006 Elsevier B.V. All rights reserved.