响应面法优化微波法提取荷叶中总黄酮的研究

采用微波提取法对荷叶总黄酮进行提取,通过响应面试验分析确定最佳的荷叶总黄酮的最佳提取工艺:微波功率346.57W,微波时间1.04min,料液比1:28.21,乙醇浓度69.65%,理论提取率为5.02%。经3次平行试验的实际平均提取率为4.98%。     

银杏叶总黄酮的超声波提取法

本文通过单因素实验和正交实验,确定了超声波法提取银杏叶中黄酮类化合物的最佳提取工艺,并与常规乙醇浸提法,微波提取法作了比较研究。实验表明：超声波提取法优于常规乙醇浸提法和微波提取法。超声波法的最佳操作条件为：320W超声波功率,温度30℃,70％乙醇,在液固比15：1条件下提取10min,连续提取2次,总黄酮提取率可达94．1％。     

提取防风多糖的工艺优化

采用超声波强化和微波辅助提取2种方法提取防风多糖,并与传统热水浸提法在多糖的提取率上进行比较。防风多糖超声提取的最佳工艺条件为超声功率1 000 W、提取时间25 min、液固体积质量比为25,防风多糖微波提取的最佳工艺条件为微波功率560 W、液固体积质量比为30、提取时间10 min,在最佳提取工艺下,2种方法的提取率分别为6.103%和7.639%。与传统热水浸提法相比,超声法和微波法提取防风多糖具有迅速、节能、高效、提取率高等诸多优点。     

咸草总黄酮提取工艺的比较研究

通过超声波法与乙醇回流法分别提取咸草总黄酮,两者均采用L₉(3⁴)正交实验方法,并运用SPSS11.5软件统计分析。结果如下:超声波法的最佳提取条件为超声波功率400W、乙醇浓度60%、料液比1:60、超声波作用时间10min,样品总黄酮含量为1.558%;乙醇回流法的最优条件为水浴温度90℃、乙醇浓度60%、料液比1:60、回流时间1.5h,总黄酮含量2.011%。两种方法比较:乙醇回流法提取总黄酮含量较高,而超声波法更节省时间。     

水浴回流与超声波辅助回流提取百合皂苷工艺比较研究

分别采用单因素试验法和正交试验法对水浴和超声波辅助回流提取法对百合总皂苷的提取工艺进行比较,获得最佳水浴回流提取工艺为:乙醇浓度为50%、温度为90℃、提取时间为3 h、固液比为1∶18。在该工艺条件下百合皂苷的提取率为1.98%;超声波辅助回流提取最佳工艺为:温度为90℃、乙醇浓度为70%、提取时间为25 min、固液比为1∶30、提取功率为105 W。在该工艺条件下百合皂苷的提取率为2.33%,超声波辅助回流提取法的百合皂苷提取率和稳定性、重复性都优于传统的水浴回流提取法。     

核桃楸叶片中总黄酮的最佳提取工艺研究

利用超声波法对核桃楸叶片中总黄酮的提取工艺进行了研究,在单因素试验的基础上,采用正交试验法,确立最佳提取条件,考察乙醇浓度、提取温度、液料比和提取时间对核桃楸叶片总黄酮提取率的影响。结果表明：超声波法辅助提取核桃楸叶片总黄酮的最适工艺参数是浸提剂乙醇浓度为70%,提取温度为50℃,液料比为20：1,提取时间为20 min,且总黄酮提取率可达4.458%。     

凤眼莲总黄酮最佳提取条件的探讨

目的：研究从凤眼莲（Eichhornia crassipes）中提取总黄酮的最佳提取条件。方法：以乙醇为溶剂,采用浸提法和超声波法提取凤眼莲总黄酮,通过单因素实验比较两种提取方法;并对黄酮提取物的抗氧化性进行了研究。结果：浸提法提取凤眼莲中总黄酮的最佳工艺条件：乙醇50%、提取温度70℃、提取时间3h、料液比1：40,总黄酮提取率4.30%;超声波法提取凤眼莲总黄酮的最佳工艺条件：乙醇50%、提取时间30min、料液比1：40、超声功率320W,提取率5.09%;凤眼莲总黄酮清除.OH的能力比甘露醇强,而清除.O2-的能力低于Vc。结论：超声波法是提取黄酮类物质较为理想的途径,凤眼莲总黄酮具有一定抗氧化活性。     

响应面法优化蕤核叶片总黄酮提取工艺

采用超声波辅助提取的方法从蕤核叶片中提取总黄酮.利用响应面法(RSM法)研究了超声提取时间、乙醇浓度、液固比、提取温度等因素对总黄酮得率的影响,确定了超声波辅助提取蕤核叶片总黄酮的最佳工艺参数.结果表明,超声波辅助提取蕤核叶片总黄酮的最佳工艺务件为:超声时间50.1 min,乙醇浓度59.5%,液料比24.9:1,提取...     

黄芪多糖超声-微波协同提取研究

本论文采用超声-微波协同提取新工艺,通过单因素实验分别考察提取时间、微波功率、料液比等因素对黄芪多糖提取率及纯度的影响;通过正交实验得出最佳提取工艺参数;通过平行提取实验,与水提法、微波及超声波辅助提取进行比照。得出最佳提取条件为微波功率120 W,提取时间为150 s,料液比1∶25(g/mL)时,黄芪多糖的提取率最高达4.25%,并且证明了超声微波协同提取法的提取效率高于水提法、微波法及超声波法等传统的提取方法。     

超声波法提取大枣多糖工艺的优化

为了进一步提高大枣多糖的提取效率,本文通过正交试验优化了超声波法提取大枣多糖的工艺条件。考察的因素包括料液比、超声功率、超声时间和浸提温度。结果显示超声波法提取大枣多糖的最佳提取工艺条件为:料液比1∶30、超声功率80W、超声时间10min,浸提温度80℃。在此工艺条件下大枣多糖的提取率达到6.97%。该工艺条件下提取率较高,因此适合于提取大枣中的多糖类化合物。     

On the origin of the Hirudinea and the demise of the Oligochaeta

The phylogenetic relationships of the Clitellata were investigated with a data set of published and new complete 18S rRNA gene sequences of 51 species representing 41 families. Sequences were aligned on the basis of a secondary structure model and analysed with maximum parsimony and maximum likelihood. In contrast to the latter method, parsimony did not recover the monophyly of Clitellata. However, a close scrutiny of the data suggested a spurious attraction between some polychaetes and clitellates. As a rule, molecular trees are closely aligned with morphology-based phylogenies. Acanthobdellida and Euhirudinea were reconciled in their traditional Hirudinea clade and were included in the Oligochaeta with the Branchiobdellida via the Lumbriculidae as a possible link between the two assemblages. While the 18S gene yielded a meaningful historical signal for determining relationships within clitellates, the exact position of Hirudinea and Branchiobdellida within oligochaetes remained unresolved. The lack of phylogenetic signal is interpreted as evidence for a rapid radiation of these taxa. The placement of Clitellata within the Polychaeta remained unresolved. The biological reality of polytomies within annelids is suggested and supports the hypothesis of an extremely ancient radiation of polychaetes and emergence of clitellates.     

On the ontogeny of the haptor and the evolution of the Monogenea

Data on the ontogeny of the posterior haptor of monogeneans were obtained from more than 150 publications and summarised. These data were plotted into diagrams showing evolutionary capacity levels based on the theory of a progressive evolution of marginal hooks, anchors and other attachment components of the posterior haptor in the Monogenea (Malmberg, 1986). 5 + 5 unhinged marginal hooks are assumed to be the most primitive monogenean haptoral condition. Thus the diagrams were founded on a 5 + 5 unhinged marginal hook evolutionary capacity level, and the evolutionary capacity levels of anchors and other haptoral attachement components were arranged according to haptoral ontogenetical sequences. In the final plotting diagram data on hosts, type of spermatozoa, oncomiracidial ciliation, sensilla pattern and protonephridial systems were also included. In this way a number of correlations were revealed. Thus, for example, the number of 5 + 5 marginal hooks correlates with the most primitive monogenean type of spermatozoon and with few sensillae, many ciliated cells and a simple protonephridial system in the oncomiracidium. On the basis of the reviewed data it is concluded that the ancient monogeneans with 5 + 5 unhinged marginal hooks were divided into two main lines, one retaining unhinged marginal hooks and the other evolving hinged marginal hooks. Both main lines have recent representatives at different marginal hook evolutionary capacity levels, i.e. monogeneans retaining a haptor with only marginal hooks. For the main line with hinged marginal hooks the name Articulon-choinea n. subclass is proposed. Members with 8 + 8 hinged marginal hooks only are here called Proanchorea n. superord. Monogeneans with unhinged marginal hooks only are here called Ananchorea n. superord. and three new families are erected for its recent members: Anonchohapteridae n. fam., Acolpentronidae n. fam. and Anacanthoridae n. fam. (with 7 + 7, 8 + 8 and 9 + 9 unhinged marginal hooks, respectively). Except for the families of Articulonchoinea (e.g. Acanthocotylidae, Gyrodactylidae, Tetraonchoididae) Bychowsky's (1957) division of the Monogenea into the Oligonchoinea and Polyonchoinea fits the proposed scheme, i.e. monogeneans with unhinged marginal hooks form one old group, the Oligonchoinea, which have 5 + 5 unhinged marginal hooks, and the other group form the Polyonchoinea, which (with the exception of the Hexabothriidae) has a greater number (7 + 7, 8 + 8 or 9 + 9) of unhinged marginal hooks. It is proposed that both these names, Oligonchoinea (sensu mihi) and Polyonchoinea (sensu mihi), will be retained on one side and Articulonchoinea placed on the other side, which reflects the early monogenean evolution. Except for the members of Ananchorea [Polyonchoinea], all members of the Oligonchoinea and Polyonchoinea have anchors, which imply that they are further evolved, i.e. have passed the 5 + 5 marginal hook evolutionary capacity level (Malmberg, 1986). There are two main types of anchors in the Monogenea: haptoral anchors, with anlages appearing in the haptor, and peduncular anchors, with anlages in the peduncle. There are two types of haptoral anchors: peripheral haptoral anchors, ontogenetically the oldest, and central haptoral anchors. Peduncular anchors, in turn, are ontogenetically younger than peripheral haptoral anchors. There may be two pairs of peduncular anchors: medial peduncular anchors, ontogentically the oldest, and lateral peduncular anchors. Only peduncular (not haptoral) anchors have anchor bars. Monogeneans with haptoral anchors are here called Mediohaptanchorea n. superord. and Laterohaptanchorea n. superord. or haptanchoreans. All oligonchoineans and the oldest polyonchoineans are haptanchoreans. Certain members of Calceostomatidae [Polyonchoinea] are the only monogeneans with both (peripheral) haptoral and peduncular anchors (one pair). These monogeneans are here called Mixanchorea n. superord. Polyonchoineans with peduncular anchors and unhinged marginal hooks are here called the Pedunculanchorea n. superord. The most primitive pedunculanchoreans have only one pair of peduncular anchors with an anchor bar, while the most advanced have both medial and lateral peduncular anchors; each pair having an anchor bar. Certain families of the Articulonchoinea, the Anchorea n. superord., also have peduncular anchors (parallel evolution): only one family, the Sundanonchidae n. fam., has both medial and lateral peduncular anchors, each anchor pair with an anchor bar. Evolutionary lines from different monogenean evolutionary capacity levels are discussed and a new system of classification for the Monogenea is proposed.In agreeing to publish this article, I recognise that its contents are controversial and contrary to generally accepted views on monogenean systematics and evolution. I have anticipated a reaction to the article by inviting senior workers in the field to comment upon it: their views will be reported in a future issue of this journal. EditorIn agreeing to publish this article, I recognise that its contents are controversial and contrary to generally accepted views on monogenean systematics and evolution. I have anticipated a reaction to the article by inviting senior workers in the field to comment upon it: their views will be reported in a future issue of this journal. Editor