香梨果实成熟衰老过程中4种内源激素的变化

以库尔勒香梨[白梨(PyrusbretschneideriRehd.)的变种]为材料,在果实生长发育、成熟衰老期间检测内源IAA、GA3、ABA、乙烯含量变化规律及其相互关系。结果表明果实发育初期IAA、GA3、ABA含量最高,有利于幼果坐果;CA3与ABA的比值变化对果实迅速膨大起关键作用;高浓度GA3对阻抑叶绿素分解起明显作用;果实成熟衰老期间,IAA含量与乙烯释放速率呈方向相同的变化;在此期间GA3含量变化与乙烯释放变化相反。     

Organogenesis of Staminate Flowers in the Genus Schisandra and Its Systematic Significance

The great morphological variation in staminate flowers makes it favorable for its use as the main criteria for infrageneric classification in the genus Schisandra (Schizandra) Michx. Organogenesis of different kinds of the staminate flowers has been observed under SEM. Combined with other currently available studies, the patterns of morphogenesis of the staminate flowers are categorized into three types: the columnar-torus type, the flattened-torus type, and the spherical-torus type. In the columnar-torus type, the torus of the staminate flower is kept columelliform through out the whole ontogenic process of the flower; this type can be further divided into two subtypes—the sphenantheraceous subtype, with the thecae laterally localized on both sides of the connective of the mature stamen, and the grandifloraceous subtype, instead with the thecae located outward or slightly outward. In the flattened-torus type, the torus of the staminate flower gradually becomes swollen and then flattened in the process of floral development, and forms a pentagonal shield together with the enlarged filaments and connectives of the stamen. The torus of the staminate flower in the spherical-torus type becomes carnified and swollen with the stamen growing into the depressions or cavities of the spherical torus. Among the three types, the columnar-torus one might be the primitive type, from which the other two were derived representing two different evolutionary trends respectively. By analyzing the cause of the morphological variation of the staminate flowers, it is suggested that the evolutionary pressure by the insect eating during pollinating enhanced the drastic differentiation of the morphology of the staminate flowers. In some taxa of the genus, in which the Coleoptera acted as the main pollinating agent, the enlargement of the torus of the staminate flower to form a thick flattened shield or a spheroid might be an adaptive fitness to the phylogenetic decreasing in number of the stamen. The primitiveness in stamen morphology of the Schisandra staminate flowers is also discussed, which might agree with the origin antiquity of the genus. The similarity of its heteropolar 3- or 6-aperturate pollen to the 3-aperturate pollen of Eudicots might result from convergent evolution. In addition, main infrageneric classifications of Schisandra and the systematic p     

北五味子果实超临界CO2萃取工艺的研究

通过正交设计的试验方法,探讨了超临界CO₂法萃取五味子果实中木脂素的工艺条件,确定了最佳工艺条件为萃取压力30 Mpa,萃取温度50℃,萃取时间120 min。     

Schisandrin B elicits a glutathione antioxidant response and protects against apoptosis via the redox-sensitive ERK/Nrf2 pathway in AML12 hepatocytes

Abstract

This study examined the effects of (?)schisandrin B [(?)Sch B] on MAPK and Nrf2 activation and the subsequent induction of glutathione antioxidant response and cytoprotection against apoptosis in AML12 hepatocytes. Pharmacological tools, such as cytochrome P-450 (CYP) inhibitor, antioxidant, MAPK inhibitors and Nrf2 RNAi, were used to delineate the signalling pathway. (?)Sch B caused a time-dependent activation of MAPK in AML12 cells, particularly the ERK1/2. The MAPK activation was followed by an enhancement in Nrf2 nuclear translocation and the eliciting of a glutathione antioxidant response. Reactive oxygen species arising from a CYP-catalysed reaction with (?)Sch B seemed to be causally related to the activation of MAPK and Nrf2. ERK inhibition by U0126 or Nrf2 suppression by Nrf2 RNAi transfection almost completely abrogated the cytoprotection against menadione-induced apoptosis in (?)Sch B-pre-treated cells. (?)Sch B pre-treatment potentiated the menadione-induced ERK activation, whereas both p38 and JNK activations were suppressed. Under the condition of ERK inhibition, Sch B treatment did not protect against carbon tetrachloride-hepatotoxicity in an in vivo mouse model. In conclusion, (?)Sch B triggers a redox-sensitive ERK/Nrf2 signalling, which then elicits a cellular glutathione antioxidant response and protects against oxidant-induced apoptosis in AML12 cells.     

Relaxant effects of Schisandra chinensis and its major lignans on agonists-induced contraction in guinea pig ileum

In this study, the herbal extracts of Schisandra chinensis were demonstrated to inhibit the contractions induced by acetylcholine (ACh) and serotonin (5-HT) in guinea pig ileum, and the 95% ethanol extract was more effective than the aqueous extract. Analysis with High Performance Liquid Chromatography (HPLC) indicated that schisandrin, schisandrol B, schisandrin A and schisandrin B were the major lignans of Schisandra chinensis, and the ethanol extract contained higher amount of these lignans than the aqueous extract. All four lignans inhibited the contractile responses to ACh, with EC₂₀ values ranging from 2.2 ± 0.4 μM (schisandrin A) to 13.2 ± 4.7 μM (schisandrin). The effectiveness of these compounds in relaxing the 5-HT-induced contraction was observed with a similar magnitude. Receptor binding assay indicated that Schisandra lignans did not show significant antagonistic effect on muscarinic M3 receptor. In Ca²⁺-free preparations primed with ACh or KCl, schisandrin A (50 μM) attenuated the contractile responses to cumulative addition of CaCl₂ by 37%. In addition, schisandrin A also concentration-dependently inhibited ACh-induced contractions in Ca²⁺-free buffer. This study demonstrates that Schisandra chinensis exhibited relaxant effects on agonist-induced contraction in guinea pig ileum, with schisandrin, schisandrol B, schisandrin A and schisandrin B being the major active ingredients. The antispasmodic action of schisandrin A involved inhibitions on both Ca²⁺ influx through L-type Ca²⁺ channels and intracellular Ca²⁺ mobilization, rather than specific antagonism of cholinergic muscarinic receptors.     

华中五味子染色体制片优化及核型分析

比较不同预处理和解离方法对华中五味子染色体制片的影响,采用华中五味子的萌发芽、新枝茎尖、幼叶等不同部位进行染色体制片,观察500个细胞,比较不同部位中期细胞和适宜核型分析的中期细胞所占比例,结果显示,0.1%秋水仙素预处理1 h、1 mol/L盐酸常温解离12 min制片所得染色体分散效果最佳。5~15 mm幼叶侧边组织制片最适宜华中五味子核型分析。核型公式为2n=2x=28=26 m 2sm,核型不对称系数(As.k)为56.30%,属于1B类型,核型对称性程度高,表明华中五味子在进化中处于比较原始类型。     

大血藤不同器官黄酮类化合物含量的季节变化

大血藤〔Ｓａｒｇｅｎｔｏｄｏｘａｃｕｎｅａｔａ (Ｏｌｉｖ .)Ｒｅｈｄ .ｅｔＷｉｌｓ.〕隶属木通科 (Ｌａｒｄｉｚａｂａｌａｃｅａｅ)大血藤属 (ＳａｒｇｅｎｔｏｄｏｘａＲｅｈｄ .ｅｔＷｉｌｓ.) ,为落叶木质藤本 ,根和藤可入药 ,有强筋骨、活血散瘀、止痛、通经之效 ,并可治疗阑尾炎、风湿性关节炎等 ,又可用作杀虫剂[1] 。大血藤是中国特有中药材 ,入药部位为一年生嫩茎 ,但在中医临床应用上并不广泛。有关大血藤次生代谢产物的研究较少。Ｒｏｍｋｅｒ等从大血藤分离出三萜类皂素如儿茶素等 ,并发现在体内具有明显的抗病毒效应[2 ] …     

五味子属种子形态及其分类学意义

用光学显微镜及扫描电镜对五味子属（Schisandra)10种96号样品的种子宏观形态和种皮的微观形态特征进行观察,首次对该属的种皮微观形态特征进行系统报道,并编排有分种检索表。研究结果表明：该属的种子宏观形态呈现平滑、细皱纹或瘤状突起,并认为五味子属种子形态可有从平滑到有细皱纹再到有瘤状突起的演化趋势;该属种皮表面微观形态可分为疣状突起型和网纹型。结合其它性状,本文认为网纹型所代表的两种植物应与本属中其它植物建立并列的分类单元。五味子属植物在种子形态特征上存在一定的差异,可为属以下、种以上的分类提供依据,并为探讨该属的系统演化提供有价值的参考资料。     

Ontogeny of Staminate and Carpellate Flowers of Schisandra sphenanthera(Schisandraceae)

The ontogenetic process of the staminate and carpellate flowers of Schisandra sphenanthera Rehd. et Wils., an endemic species to China, was observed for the first time under the scanning electron microscope (SEM). In the staminate flowers, the perianth units and stamens were initiated acropetally in a continuous fasion with 2/5 spiral phyllotaxis, while no female structures were formed. Anthers were differentiated prior to the filaments formation. Throughout all the stages were the stamens arranged spirally on a columniform receptacle. In the carpellate flowers, the initiation sequence of the perianth units and carpels were similar to that of the staminate flowers. In contrast, no male structures were formed. Shortly after initiation, the carpel primordia began their marginal growth besides the apical growth and then appresses were formed on the adaxial surfaces of the primordia. However the lower margins of these appresses were inconspicuous, resulting in conduplicate carpels. Two ovules were developed on the inner surface near either lateral margins of the carpel, shaping laminar placentae. Compared with S. glabra (Brickell) Rehd., a related American species, the evolutionary trend of phyllotaxis of androecia is considered that stamens may change from spiral to approximately whorled arrangement, accompanying with the change of receptacle from a column to a flattened shield. It was also suggested that the stamens being numerous and uncertain in number become certain and decrease in number to 5 (4－7). Sterile stamens are observed and the unisexual nature of the flowers is discussed. Two types of carpel primordia are categorized, corresponding to two types of carpels, namely, ascidiate and conduplicate carpels, respectively.     

安徽黄山华中五味子次生木质部的生态解剖

对安徽黄山海拔420～1840m的华中五味子茎的次生木质部进行了生态解剖学研究。结果表明,茎的次生木质部为散孔材,导管分子长741.7～1025.2μm,直径为152.4～191.9μm;导管频率60.6～70.2mm-2。纤维管胞长925.2～1046.3μm;木射线类型为异形ⅡA和ⅡB,单列射线高682.1～778.4μm,多列射线高度为1093～1208μm,多列射线宽63.6～92.6μm,射线频率9.2～12.8mm-1。次生木质部解剖特征随异质生境而表现出一定的可塑性,其中,多列射线宽、射线频率、导管分子长度、导管直径等性状的可塑性较大。多重回归分析表明,水分和温度是影响华中五味子次生木质部解剖特征的主导因子。随着空气相对湿度的增加,导管分子长度和直径均增大,射线频率减小。随着降雨量的增加,纤维长度增加。随着最冷月温度的增加,导管频率增加,多列射线宽度减小。随着年较差的增加,单列射线和多列射线高度均减小。