忍冬和华南忍冬叶表皮扫描电镜观察及其生态适应性研究

利用扫描电镜观察了忍冬（Lonicera jàponica Thunb）和华南忍冬（Lonicera confus）叶表皮形态特征,观察指标包括：气孔器、表皮毛、表皮细胞等.结果表明：气孔仅分布在下表皮,气孔器呈无规则型散生;上表皮细胞的垂周壁呈沟槽状下陷;下表皮密被表皮毛（包括腺状毛和非腺毛）,同时还分布有瘤状的草酸钙簇晶.为进一步证明这种瘤状结构是否为草酸钙簇晶,作者发现利用Fluo-3/AM（钙离子荧光指示剂）处理的活体叶片在激光共聚焦显微镜下能够发出强烈的荧光.此外,通过电子探针对瘤状物进行分析,发现其元素组成为C、O、Ca.上述叶表皮构造特征,有利于减少植物体水分散失,还有助于植物适应富钙的石灰土,从而适应我国西南岩溶区特殊的干旱、富钙的环境.电镜观察结果表明,在忍冬叶上表皮中脉处有呈线状分布的腺状表皮毛,而华南忍冬叶上表皮则无表皮毛分布,这一微形态特征可以作为二者种间特异性差别,从而为二者的合理区分提供一定的依据.     

3,5-Dicaffeoylquinic acid isolated from Artemisia argyi and its ester derivatives exert anti-Leucyl-tRNA synthetase of Giardia lamblia (GlLeuRS) and potential anti-giardial effects

An aqueous ethanol extract of Artemisia argyi inhibited the aminoacylation activity of LeuRS from Giardia lamblia (GlLeuRS). The bioassay-guided fractionation of the extract led to the isolation of 3,5-dicaffeoylquinic acid (1), with an IC(50) of 5.82μg/mL. The ester derivatives of 1 were also found to possess strong anti-GlLeuRS effects, with IC(50) values of 1.79, 5.51 and 2.56μg/mL respectively. Anti-giardial assay showed that the derivatives, especially 3,5-dicaffeoylquinic acid propyl ester (4) (IC(50)=4.62μg/mL), were effective at killing G. lamblia.     

金银花分体压藤繁殖试验

试验设置药品种类、浸药时间、藤条长度3种因素的多重处理其对金银花分体压藤繁殖中藤条出根率、出根数量、出根长度、萌芽率的影响,试验结果表明:藤条长度是影响金银花分体压藤繁殖的主要因素,药品种类的作用次之,浸药时间作用不明显.     

Constituents of Craspedolobium schochii

Nine phenolic compounds, including a new one, were isolated from 70% acetone extract of Craspedolobium schochii. The new compound was identified as 3-(3,4-dimethoxy-2-hydroxyphenyl)-7-hydroxy-coumarin (1) on the basis of spectroscopic evidence.     

Chemical modification of rain water byAlnus japonica wetland forest in Kiritapp mire, eastern Hokkaido, Japan

A survey was made of seasonal changes in pH and electronic conductivity (EC) of precipitation inAlnus japonica (Thunb.) Steud. forest in Kiritapp mire, Hokkaido, Japan. The average pH of throughfall and stem flow was higher than that of bulk deposition. When the pH of bulk deposition exceeded 5.5, however, pH of throughfall and stem flow was lower than that of bulk deposition. The EC of stem flow was always higher than throughfall, and that of throughfall higher than that of bulk deposition. The EC of stem flow was highest during the first defoliation period ofA. japonica. On the other hand, the differences in the EC of throughfall and bulk deposition was very few just after the first defoliation period ofA. japonica. This implies that the chemical properties of throughfall and stem flow are strongly affected by the phenology of the plants.     

Absolute configuration of new bisaboranoids from Yaku-sugi (Cryptomeria japonica) wood

The absolute configuration of bisabolanoids isolated from Yaku-sugi wood were compared with those of dihydrocarvone and dihydrocarveol isomers based on their¹³C nuclear magnetic resonance data and optical rotations.     

Constituents and cytotoxicity of Zanthoxylum rhesta stem bark

3,5-Dimethoxy-4-geranyloxycinnamyl alcohol (1), 8-methoxy-N-methylflindersine (2), xanthyletin and sesamin have been isolated from petroleum ether extract of the stem bark of Zanthoxylum rhesta. The petroleum ether extract and 8-methoxy-N-methylflindersine showed cytotoxicity on brine shrimp nauplii.     

Constituents of aromatic plants: carvacrol

Carvacrol is a component of numerous aromatic plants. Up to now, no toxicological data were available. Carvacrol show a weak activity in the mutagenicity studies. Moreover, in the metabolism study, carvacrol has shown to be excreted with urine after 24 h in large quantities or unchanged or as glucoronide and sulphate conjugates. The available data do not allow the assessment of the NOEL. Further toxicological studies are needed.     

Individual variations in monoterpenes released from Cryptomeria japonica and Pinus thunbergii needles

Variations in the compositions of low boiling point (LBP) monoterpenes in needle samples from 99 sugi (Cryptomeria japonica) and 100 kuromatsu (Pinus thunbergii) trees were investigated using a headspace technique. Considerable variations in the proportions of monoterpenes were revealed in both species. In sugi, the proportions of sabinene and α-pinene in the total LBP monoterpenes, ranging from 8.8% to 73.3% and from 14.5% to 73.3%, respectively, showed enormous variations among nine monoterpenes. The proportions of 3-carene and limonene, ranging from 0.1% to 29.5% and from 0.2% to 20.4%, respectively, also showed very specific variations. In kuromatsu, the proportions of β-pinene and α-pinene in the total LBP monoterpenes, ranging from 26.5% to 66.3% and from 18.7% to 46.9%, respectively, showed considerable variations among ten monoterpenes. The proportions of myrcene and 1,8-cineole, ranging from 0.9% to 18.5% and from 0.8% to 12.3%, respectively, also showed specific variations. Part of this article was presented at the 50th Annual Meeting of the Japan Wood Research Society, Kyoto, April, 2000, and the 13th Annual Meeting of the Chugoku Shikoku Branch of the Japan Wood Research Society, Okayama, September 2001     

Underplanting Cherrybark Oak (Quercus pagoda Raf.) Seedlings on a Bottomland Site in the Southern United States

We initiated a study on a bottomland site in the southern United States to examine the effects of Japanese honeysuckle (Lonicera japonica Thunberg) control and seedlings of two root classes on survival and growth of underplanted cherrybark oak (Quercus pagoda Raf.) seedlings. Three honeysuckle control treatments were assigned to nine 0.5-ha plots in a stand harvested to 30% residual stocking. Treatments included a spring 1997 herbicide application (Escort^®, metsulfuron-methyl), a similar application in the late summer of 1997, and a control (no herbicide application). In 1998, half of each treatment plot was planted with seedlings having four or more first-order lateral roots > 1 mm in diameter, while the other half of each plot received seedlings with fewer than four lateral roots. Four years after treatment, the early season application reduced honeysuckle biomass 60% relative to the other treatments, but we did not observe a survival or growth response by underplanted seedlings. Three years after establishment, seedlings that initially had four or more lateral roots were 16% taller and 18% larger in root-collar diameter than seedlings in the other class, but these differences were primarily due to initial size differences maintained through the study period. Over all treatments, oak seedlings averaged 87% survival while showing a 300% increase in height and a 170% increase in root-collar diameter 3 years after planting. Our results suggest that partial stand harvesting followed by underplanting may be a viable approach for establishing cherrybark oak reproduction on bottomland sites of the southern United States.     

Three triterpenoid saponins from the roots of Polygala japonica Houtt

Three new triterpenoid saponins polygalasaponins LI-LIII (1-3) with two acylation groups in oligosaccharide chain, together with three known saponins were isolated from the roots of Polygala japonica Houtt. (4-6). The neuroprotective effects of these compounds on neuron-like PC12 cells were evaluated in vitro. Compounds 5 and 6 show neuroprotective effects in Aβ(25-35) model at the concentration of 10μM.     

Age structure and dynamics of Zoysia japonica module population

The age structure of the natural Zoysia japonica clonal population at Qipan Mountain in Huishan Scenic Spot of Shenyang,Liaoning Province, China was studied using the morphological method in 2003 and 2004. The dynamics of leaves were recorded and the dynamics of tiller and rhizome in the growing season were observed. The results indicated that the rhizomes formed in different years changed in color and rigidity. Its internodes produced in autumn became shorter. The number of naked nodes changed with the tiller age.Rhizome and tiller characters were used as a foundation for judging the ages of modules in this study. The longevity of tiller and rhizome was 3 years at most. At the beginning of the growing season, 2-year-old tillers and rhizomes predominated. Then I -year-old tillers and rhizomes increased rapidly and became dominant in July. The proportion of buds to tillers on quantity was stable at about 30% in the mid-phase of the growing season and rose to about 50% in autumn. The seasonal dynamics of tiller, rhizome and bud was very important to guarantee the sustained existence of the Zoysia japonica population. The turnover of modules was the mechanism of sustaining the rejuvenation of the Zoysia japonica clonal population.     

Cytological study of a male-sterile Cryptomeria japonica that does not release microspores from tetrads

To determine the mechanism of male-sterility Cryptomeria japonica tree Shindai3, the process of microspore development was observed under light and fluorescence microscopy. Microspore development in the Shindai3 was normal until the tetrad stage, but separation of the microspores from the tetrads was not observed even after callose had been degraded. In contrast to the microspore stage in a male-fertile tree, amorphous substances were observed around tetrads in the Shindai3, and the amount of the amorphous substance increased from the middle of November to the middle of December. The substances are hypothesized to prevent the separation of individual microspores from tetrads by inducing adhesion between microspore cells within the tetrad or enclosing the tetrads. The form of the tetrads in the Shindai3 was maintained until just before the pollen dispersal season, but they ultimately degenerated. The results of this study indicate that the mechanism causing male sterility in Shindai3 differs from that previously reported for other male-sterile trees of C. japonica.     

Essential oil from the leaves of Cryptomeria japonica acts as a silverfish (Lepisma saccharina) repellent and insecticide

This is the first article to report the evaluation of a natural product used as an antisilverfish agent. Silverfish (Lepisma saccharina), primitive wingless insects, feed on a variety of materials, including paper, cotton, starch, and cereals. They can be a problem in libraries and other places where books, documents, and papers are stored. In this pilot study, the essential oil from leaves of Cryptomeria japonica was investigated to test its properties as a silverfish repellent and insecticide. The results from a repellency bioassay show that the essential oil significantly repelled silverfish. The repellent activity was 80% at a dosage of 0.01 mg/cm³. When silverfish were exposed to a concentration of 0.16 mg/cm³ of essential oil, they were killed within 10h. The chemical composition of essential oil, the emissions from a test chamber, and the residue left on filter papers previously soaked with the essential oil in a chamber were analyzed by gas chromatography-mass spectrometry. The components of the essential oil were found to be: elemol (18.22%), 16-kaurene (11.63%), 3-carene (9.66%), sabinene (9.37%), 4-terpineol (9.06%), β-eudesmol (5.70%), α-pinene (5.62%), and limonene (5.26%). Only some constituents of the essential oil compounds collected by solid-phase microextraction were found to be emitted in the test chamber. The main constituents were: 3-carene (21.03%), p-cymene (10.95%), limonene (9.49%), β-myrcene (9.39%), γ-terpinene (9.10%), α-terpinene (8.57%), and 4-terpineol (7.97%).     

Constituents of the flowers of Punica granatum

A new polyphenol compound named pomegranatate (1), together with, ellagic acid, 3,3',4'-tri-O-methylellagic acid, ethyl brevifolincarboxylate, urolic and maslinic acids, and daucosterol were isolated from the ethanolic extract of the flowers of Punica granatum. The structure of compound 1 was determined by spectroscopic analysis. Maslinic acid exhibited antioxidant activity, evaluated by measurement of LDL susceptibility to oxidation.     

In vitro screening of angiotensin I-converting enzyme inhibitors from Japanese cedar (Cryptomeria japonica)

Screening and isolation of angiotensin I-converting enzyme (ACE) inhibitors from Japanese cedar (Cryptomeria japonica) based on the in vitro ACE inhibitory assay were attempted. The ethanol extract from outer bark showed the highest inhibitory activity (IC₅₀ is 16g/ml) among 24 extracts prepared from roots, leaves, heartwood, sapwood, inner bark, and outer bark by successive extraction with four solvents. The fractionation of the outer bark ethanol extract followed by the bioassay resulted in the isolation of two strong ACE inhibitors, catechin and dimeric procyanidin B3. The bioassay of three flavan-3-ols including (+)-catechin and six flavones revealed that most of these compounds have high ACE inhibitory activity. The results suggest that the phenolic hydroxyl group at the C7 position and heterocyclic oxygen atom of these compounds are important for expressing the inhibitory activity.     

Somatic embryogenesis from immature and mature zygotic embryos ofCryptomeria japonica I: Embryogenic cell induction and its morphological characteristics

Embryogenic cells (ECs) of sugi (Cryptomeria japonica D. Don) were induced from immature and mature zygotic embryos cultured on different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D)-containing modified Campbell and Durzan medium. The rate of induction of ECs varied depending on the stage of embryos collected. The highest percentage of induction (35%) was obtained with immature zygotic embryos collected July 18 and July 30, 1997, when 1 M of 2,4-D was added to the induction medium. The ECs easily proliferated when subcultured in a medium of the same composition as the induction medium within 3 weeks. Morphological characteristics of nonembryogenic cells and embryogenic cells of different developmental stages were studied under an inverted fluorescence microscope.Part of this work was presented at the 109th annual Japanese Forestry Society meeting at Tochigi, April 1998     

Inheritance of the trait of male sterility inCryptomeria japonica

Matings of male-sterileC. japonica and fertile eliteC. japonica, as well as backcross seedlings of male-sterile trees, were carried out to clarify the genetic trait of male sterility of theC. japonica. The seeds from male-sterileC. japonica were germinated in an incubator and grown them in the greenhouse between 1994 and 1997. The seedlings were treated with 100 ppm gibberellin at early July 1994 and early July 1995 to promote the formation of male flowers. In the middle of January 1995, the male flowers of all seedlings were examined under the microscope to confirm the production of pollen. In January 1996, pollen did not developed in to the male flowers from the seedlings between the fertiled elite and backcrossC. japonica. In January 1997, all seedlings of eliteC. japonica produced pollen in their male flowers; however, pollen did not developed in 55 out of 120 backcrossed seedlings. This evidence suggests that the heredity pattern of male sterility inC. japonica is nuclear male sterility controlled by a pair of recessive genes.     

Effects of stand density on the productivity ofCryptomeria japonica male flowers

We have studied male flower production and relative illumination in clonal sugi (Cryptomeria japonica) forests planted at densities of 1,500/ha, 3,000/ha, and 5,000/ha, to clarify the effects of forest management on male flower production. Both the relative illumination and male flower production decrease as the stand density increases. The lowest position at which male flowers are formed decreases as the density of the stand decreases. High thinning intensity promotes male flower production and light pruning is ineffective to reduce male flower production. Therefore, traditional management methods used in sugi forests (i.e. planting at high density, frequent light thinning, intensive pruning and short rotation) are ideal strategies for limiting male flower production.