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61.
Nguyen Thi Huong Le Thi Vien Tran Thi Hong Hanh Nguyen Hai Dang Nguyen Van Thanh Nguyen Xuan Cuong Nguyen Hoai Nam Luu Hong Truong Ninh Khac Ban Phan Van Kiem Chau Van Minh 《Bioorganic & medicinal chemistry letters》2017,27(3):557-561
Two new triterpene saponins, camelliosides I and J (1 and 2), two new megastigmane glycosides, camellistigosides A and B (3 and 4), and two known megastigmane glycosides, icariside B1 (5) and (6S,9R)-roseoside (6), were isolated from a methanol extract of the Camellia bugiamapensis leaves using various chromatographic separation techniques. Their structures were elucidated based on spectroscopic analyses, including HR ESI MS, CD, 1D and 2D NMR. Their inhibitory effects on LPS-induced NO production in RAW264.7 cells were evaluated. This is the first report of the chemical constituents and biological activity of C. bugiamapensis. 相似文献
62.
S.-X. Yang J.-B. Yang L.-G. Lei D.-Z. Li H. Yoshino T. Ikeda 《Plant Systematics and Evolution》2004,248(1-4):45-55
The combined analyses, based on ITS, trnL-F and matR DNA sequence data respectively from the nuclear, plastid and mitochondrial genomes, reveal that Gordonia is not a monophyletic group, and on the contrary, distributed in two major lineages in Theaceae. The only North American species, G. lasianthus, is located in Gordonieae together with Schima and Franklinia, whereas the Chinese Gordonia species are positioned in Theeae together with Camellia, Pyrenaria s.l. and Apterosperma. This result, to great extent, supports the viewpoints of separating the North American and Asiatic Gordonia species into two different genera, Gordonia s.str. and Polyspora, respectively.The study was partially supported by funds from a project of the Provincial Natural Sciences Foundation Committee of Yunnan, P. R. China (97C039Q), the special support grants from The Chinese Academy of Sciences for biotaxonomy and floristics. 相似文献
63.
64.
The floral development of a critically endangered plant Euryodendron excelsum from Ternstroemioideae (Theaceae) has been observed under scanning electron microscope (SEM) for the first time . The flower of E. excelsum is bisexual and teleianthous . Five sepal primordia are initiated 21089839;5 spirally and arranged in one whorl when mature , and so are petals. Sepals and petals are initiated in the same order either clockwise or counterclockwise in the same flower . The androecial part is a ring primordium in the beginning . The first five stamen primordia are initiated on this ring primordium at antisepalous positions and then other stamen primordia appear on two sides of each of the first five primordia . Finally a total of 25 stamen primordia are initiated from the ring primordium and arranged in one whorl but could be grouped into 5 fascicles. Three sequentially initiated carpels compose an ovary which has an axile- central placenta with three locules and a truncateand indehiscent stigma . The floral development of E. excelsum is distinctly different from plants in Theoideae . 相似文献
65.
为何Tutcheria championii Nakai (1940) 发表较晚, 却被《中国植物志》等志书作为正确学名;而 T. spectabilis (Champ. ex Benth.) Dunn (1908)这更早发表的名称却成了异名? 笔者在本文解释,根据《国际植物命名法规》,因T. championii这后出替代名发表时曾引用Camellia spectabilis Champ. ex Benth.,而主模式标本因此已包含在内,所以在Tutcheria属内,具相同主模式的T. spectabilis是合法名也具有优先权,应为正确学名。 相似文献
66.
中国山茶属(山茶科)一新变种——长蕊西南山茶 总被引:5,自引:0,他引:5
描述了山茶科Theaceae一个新变种--长蕊西南山茶Camellia pitardii var. longistaminata J. L. Liu &; Q. Luo。这一新变种与原变种西南山茶Camellia pitardii Cohen-Stuart的区别是花瓣较大, 长4.4-6.2(-8) cm, 宽3.1-4.4 cm; 雄蕊花丝特长, 外轮花丝长4.2-5.1 cm, 在中部或中上部合生, 内轮花丝长2.5-3 cm, 花丝管长2.3-2.8 cm。 相似文献
67.
The free sugar in the mature pollen grains of Camellia japonica is almost all sucrose and the sucrose content decreases rapidly during pollen growth. The activity of soluble invertase increases during culturing and a high constant activity was found at the later stages of pollen tube growth. By contrast, the level of sucrose synthetase activity remains constant during pollen growth and that of wall-bound invertase activity is very low. Cycloheximide has little effect on the activity of these enzymes. Exogenous sucrose or glucose was simultaneously incorporated into the pollen grains when they absorbed water and swelled. The free sugar levels in growing pollen depend on the nature of the exogenous sugar. The sugar metabolism in the pollen at the stage of germination differs from that during tube growth, the latter being particularly influenced by exogenous sugar. 相似文献
68.
The nature of the peaks eluted from Sephadex LH-20 using aqueous acetone as eluent, from whole tea brews and various ethyl acetate-soluble thearubigin fractions, were examined. Monitoring the columns at 380 nm revealed two extra peaks compared to monitoring at 460 nm, and these were attributed to the presence of two pairs of flavonol glycosides. Sharp peaks which occurred at 2.6 V0 with 60 % aqueous acetone as solvent were attributed to the action of inorganic ions contained in the samples under investigation. These, and other anomalous effects, were suppressed by electrolyte-containing eluents. 相似文献
69.
Species fromthe order “Theales” (Guttiferales) and from the Ericanae (Ebenales, Ericales, Primulales) have been examined using serological comparisons of sets of antigenic specifities (sets of determinants). The results suggest that only antigenic systems derived from species of the Theaceae and Actinidiaceae show serological correspondence of sufficient taxonomical significance towards representatives of Ericanae (except the Ebenaceae). Our results justify a scheme in which the Actinidiaceae and Theaceae occupy a central position with Styracaceae and Sapotaceae placed on one side and the families of the Ericales and Primulales occupying the other. Our serological results show no reason to justify the further existence of the “Theales”, if this is supposed to contain the Guttiferae, Dipterocarpaceae, and Ochnaceae. Further investigations on this will follow. We cannot agree with the recommendation of Takhtajan and Dahlgren to integrate the Actinidiaceae with the Ericales. We would rather place the family ner the Theaceae as most authors do. 相似文献
70.
The seasonal variations in the amounts of C6-volatile components cis-3-hexenal trans-2-hexenal n-hexanal) and their precursors (linoleic and linolenic acid) in homogenates of Thea sinensis leaves were quantitatively analyzed throughout the year. Formation of trans-2-hexenal began in the middle of April and reached a maximum during July. Towards autumn the aldehyde gradually decreased and, in winter (December to March), was virtually absent. The levels of cis-3-hexenol remained constant during May–December. cis-3-Hexenal showed a similar variation pattern to that of trans-2-hexenal. The major fatty acids in the leaves were palmitic, palmitoleic, oleic, linoleic and linolenic acid, and occurred in non-ionic lipids and phospholipid fractions. The amounts of linoleic and linolenic acid did not show any marked variation except for a big peak in October. 相似文献