盐酸小檗碱、绿原酸和黄芩苷在兔体液内浓度与其体外抑菌浓度的差异研究

 【目的】测定盐酸小檗碱、绿原酸和黄芩苷在兔体液内浓度,及各成分体外最小抑菌浓度,阐明3种中药成分清热解毒功能与其抑菌作用的关系。【方法】采用反相高效液相色谱法,测定盐酸小檗碱、绿原酸和黄芩苷在兔血液和组织液内的浓度;采用试管稀释法,测定3种中药成分对大肠杆菌的体外最小抑菌浓度。【结果】盐酸小檗碱、绿原酸和黄芩苷在兔血浆内的浓度峰值分别为3.2、5.03和7.63μg?ml-1,在兔组织液内的浓度峰值分别为0.12、0.11和0.12μg?ml-1;3种中药成分的体外最小抑菌浓度分别为1.0×103、3.75×103和6.75×103μg?ml-1,其体外最小抑菌浓度明显高于它们在兔体液内的浓度峰值。【结论】盐酸小檗碱、绿原酸和黄芩苷的抑菌作用较弱,在兔体液内不能达到有效抑菌浓度,其抑菌作用并非其清热解毒功能的主要机制。     

Acetic acid and 3-hydroxybutyric acid levels in cerebrospinal fluid of cattle

To evaluate the importance of acetic acid and 3-hydroxybutyric acid (3-HB) in cerebrospinal fluid (CSF) of cattle, CSF samples were taken from a population of 60 cattle including healthy and sick animals with central nervous disorders. Mean acetic acid and 3-HB levels in blood plasma were 0.30 (SD 0.24) and 0.30 (SD 0.28) mM, and those in CSF were 0.14 (SD 0.06) and 0.08 (SD 0.07) mM, respectively. Significant differences were observed between plasma and CSF samples for both acetic acid and 3-HB levels. Acetic acid levels in CSF showed less relationship with those in blood plasma, whereas plasma 3-HB levels accompanied proportional changes with its CSF levels, which were about 30% of plasma 3-HB. It was revealed that both acetic acid and 3-HB levels in plasma and CSF have less relationship to glucose levels in plasma and CSF; therefore, the decrease of glucose levels in plasma or CSF is not necessarily accompanied by hyperketonemia.     

蔬菜水果中的农药残留分析进展

较为详细地讨论了蔬菜水果中农药残留的分析方法,着重论述了样品的前处理过程和检测手段。一些新的样品前处理技术,像超临界流体萃取和固相分散正不断应用于农药残留分析中;质谱这一鉴定手段将会得到更广泛的应用;原子发射检测器的选择性好,能够对多元素进行同时分析检测,将会在农药残留的分析中扮演重要的角色;免疫分析法已经在农药残留分析中显示出巨大的潜力。     

成品油管道顺序输送混油模型研究进展

成品油在顺序输送过程中会产生多个混油段,混油量的精确计算对于批次定位和混油切割方案的制定具有重要意义。系统地梳理了目前成品油管道顺序输送混油计算模型,依据其建立方法将其分为经验模型、半理论半经验模型及基于计算流体力学(CFD)理论所建立的模型,对这3类模型的研究现状及局限性进行了分析。最后指出:建立考虑混油拖尾机理的数学模型及开发适用于求解湍流状态下的高维混油模型的快速耦合算法是未来成品油管道混油预测的重要研究方向。(参46)     

Chemical profiling and biological screening of Thymus lotocephalus extracts obtained by supercritical fluid extraction and hydrodistillation

Essential oil and extracts from the aerial parts of Thymus lotocephalus were obtained by hydrodistillation (HD) and supercritical fluid extraction (SFE) in two different collectors, respectively. SFE was conducted at 40 °C and a working pressure of 12 or 18 MPa. The chemical profiles were determined using GC-FID and GC-IT-MS. Oxygen-containing monoterpenes were the primary constituents in the essential oil and SFE extracts collected in the second separator, while the extracts obtained in the first separator were predominantly oxygen-containing sesquiterpenes. A large number of compounds were identified by hydrodistillation and, in contrast, the highest extraction yields were obtained using SFE. Linalool (10.43 ± 1.63%) was the main component in essential oil, whereas camphor (7.91 ± 0.84%) and cis-linalool oxide (7.25 ± 1.45%) were the major compounds in the extracts-2nd separator obtained at pressures of 12 and 18 MPa, respectively. Caryophyllene oxide was the primary constituent identified in the extracts-1st separator (4.34 ± 0.51 and 4.41 ± 1.25% obtained at 12 and 18 MPa, respectively). The antioxidant activity was assessed by ORAC and DPPH assays, and the anti-cholinesterase activity was evaluated in vitro using Ellman's method. The essential oil and SFE extracts (first separator) of T. lotocephalus possessed antioxidant activity and strongly inhibited cholinesterases. We also demonstrated that the acetylcholinesterase and butyrylcholinesterase inhibitory activities of the essential oil could be attributed to 1,8-cineole and caryophyllene oxide, respectively.     

超临界CO2萃取人参脂溶性成分的GC-MS分析

目的 用超临界CO2萃取人参脂溶性成分,分析并测定提取物的主要成分和含量.方法 用超临界CO2萃取人参脂溶性成分.提取物用气相色谱质谱(GC-MS)联用法进行分析鉴定.使用面积归一法测定各成分相对含量.结果鉴定了44个化合物,主要为脂肪酸和酯(34)、挥发油.结论用超临界萃取人参,可以较好的获得其脂溶性成分.     

金柑果皮精油超临界CO2流体萃取工艺优化及其理化性质的研究

对超临界CO2流体萃取金柑果皮精油的工艺进行优化,并研究其理化性质。结果表明,金柑果皮精油超临界CO2流体最佳萃取工艺条件为：萃取压力14 MPa,萃取温度31℃,萃取时间120 min,CO2流量26 L/h,在此优化条件下,金柑果皮精油得率为(5.08±0.03)%。金柑果皮精油理化性质研究表明,在20℃条件下,金柑果皮精油酸值为0.466 8、酯值为4.245 6、密度为0.838 g/mL、折光度为1.470 7、旋光度为1.366 8,精油与95%乙醇的互溶比例为1∶6.1。金柑果皮精油功能团鉴定结果表明,金柑果皮精油含有醇类、醛酮类、不饱和脂肪酸,不含酚类、羧酸衍生物。     

循环水养殖中水动力特性对鱼类影响的研究进展

为改善双通道方形养殖池内流场特性,通过研究圆弧角和直边的池壁组合方式对其进行流场优化,从而为循环水养殖产业提供更好的养殖装备。利用计算流体力学技术对双通道养殖池内流场进行三维数值模拟,通过对修正速度v₀和均匀系数UC₅₀的分析,评估了相对弧宽比 (R/B,R为圆弧角半径,B为池壁边长) 对池内流场特性的影响。结果表明,不同的底流分流比 (养殖池底部中心排水口的出流流量占总体出流流量的百分比) 工况均呈现相同规律,即在相同的水体交换率下,0.2≤R/B<0.4的方形圆弧角养殖池的平均流速大约为方形养殖池的2倍,而与圆形养殖池相比无明显差异;且在流场均匀性分析中发现,0.2≤R/B<0.4的方形圆弧角养殖池均匀系数较高,甚至优于圆形养殖池的流态。研究表明,方形圆弧角养殖池的圆弧角可有效缩小方形养殖池中直角所导致的低流速区域面积,且保留了较高的空间利用率。方形圆弧角养殖池结合了方形养殖池和圆形养殖池的优势,可较好地解决双通道方形养殖池内流态不佳的问题,具有良好的产业推广及应用价值。     

Measurement of equine myeloperoxidase (MPO) activity in synovial fluid by a modified MPO assay and evaluation of joint diseases - an initial case study

The aim of this study was to develop a specific myeloperoxidase (MPO) activity assay in the synovial fluid of horses and investigate whether MPO activity is increased in different forms of joint diseases. Synovial fluid samples were taken from affected joints from horses with osteoarthritis, chronic non-septic arthritis and septic arthritis, and from healthy control horses. MPO activity was measured using a specific modified o-dianisidine-assay containing 4-aminobenzoic acid hydrazide as a potent and specific inhibitor of the MPO. This assay is characterized by high reproducibility. The results reveal only a slight elevation of MPO activity in the synovial fluid of horses with osteoarthritis and chronic non-septic arthritis. However, in the cases of septic arthritis a significant increase in MPO activity was found when compared to the controls. In conclusion the first field study suggests that synovial fluid MPO may be used as a marker for septic arthritis in horses.     

CO2超临界萃取法提取苦瓜籽油及其GC-MS分析

一种野生品种苦瓜的籽用索氏提取法提取苦瓜油,测得含油率为38.0％;苦瓜籽仁粉末在CO2超临界状态下,通过正交试验法对萃取压力、温度、时间和CO2流量等因素进行筛选,确定苦瓜籽油萃取工艺参数为萃取压力37 MPa、萃取温度40℃、CO2流量40 L/h、萃取时间为2h时苦瓜籽油得率为97.2％;超临界状态下萃取的苦瓜籽油经GC-MS分析结果表明,苦瓜籽油多种不饱和脂肪酸含量达79.60％,高含量多不饱和脂肪酸的存在使其具有生物活性产品的开发价值.