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The CH(2)Cl(2)/MeOH extract of the stem bark of Erythrina vogelii (Fabaceae) from Nigeria has yielded two novel isoflavones, 7,4'-dihydroxy-8-(gamma,gamma-dimethylallyl)-2'zeta-(4'-hydroxyisopropyl)dihydrofurano[1',3':5,6]isoflavone (vogelin H) (1) and 7,4'-dihydroxy-8-[(2'zeta,3'-dihydroxy-3'-methyl)butyl]-2',2'-dimethyl-3',4'-dehydropyrano[1',4':5,6]isoflavone (vogelin I) (2), a novel flavone, 7,4'-dihydroxy-2',2'-dimethyl-3',4'-dehydropyrano[1',4':5,6]flavone (vogelin J) (3), and eight known flavonoids. 相似文献
43.
AIMS: To screen six isoflavones isolated from Erythrina poeppigiana (Leguminosae) for their antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). METHODS AND RESULTS: Stem bark of E. poeppigiana was macerated with acetone and the methylene chloride-soluble fraction of the residue was applied to repeated silica gel column chromatography and eluted. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined by a broth dilution method. Inactive compounds that failed inhibiting bacterial growth at 25 microg ml(-1) were further investigated for their combination effects with methicillin and oxacillin. Of the isolated isoflavones, 5,7,4'-trihydroxy-8,3'-di(gamma,gamma-dimethylallyl)isoflavone (isolupalbigenin) exhibited the highest anti-MRSA activity (MICs: 1.56-3.13 microg ml(-1); MBCs: 6.25-12.5 microg ml(-1)), followed by 5,7,4'-trihydroxy-6-gamma,gamma-dimethylallylisoflavone (erythrinin B). Inactive compounds were combined with methicillin or oxacillin, 5,4'-dihydroxy-(3',4'-dihydro-3'-hydroxy)-2',2'-dimethylpyrano[5',6':6,7]isoflavone (M-Wi-2) intensifying the susceptibility of MRSA strains to these antibiotics. In all but one strain, the MIC values of methicillin were reduced from > or =100 to 6.25-12.5 microg ml(-1) in the presence of M-Wi-2 (25 microg ml(-1)). CONCLUSIONS: Isoflavones from E. poeppigiana showed two different antibacterial activities against MRSA: direct growth inhibition and intensification of methicillin sensitivity. SIGNIFICANCE AND IMPACT OF THE STUDY: Isolupalbigenin and M-Wi-2 could lead to the development of compounds for new approaches against MRSA infection. 相似文献
44.
Tanaka H Hirata M Etoh H Shimizu H Sako M Murata J Murata H Darnaedi D Fukai T 《Phytochemistry》2003,62(8):1243-1246
Two 3-phenoxychromones, eryvarins F and G, were isolated from the roots of Erythrina variegata. Their structures were established to be 3-(2,4-dihydroxyphenoxy)-7-hydroxy-6,8-di(3,3-dimethylallyl)chromen-4-one and 3-(2,4-dihydroxyphenoxy)-8-(3,3-dimethylallyl)-2,2-dimethylpyrano[5,6:6,7]chromen-4-one on the basis of spectroscopic and chemical evidence. Eryvarins F and G are unusual 3-phenoxychromone derivatives with two isoprenoid groups. 相似文献
45.
Garín-Aguilar ME Valencia del Toro G Soto-Hernández M Kite G 《Phytochemical analysis : PCA》2005,16(5):302-306
A sensitive, reverse-phase HPLC-MS method for the analysis of the alkaloids of Erythrina has been developed. The method is based on the use small amounts of crude extracts (20 mg) and is sufficiently sensitive to detect the presence of the typical alkaloids, such as erysodine, erysovine, erythraline, erysopine and the hexoside of erysopine, that are representative of the title species. 相似文献
46.
Sarah Ehrlich-Rogozinski Antonio De Maio Halina Lis Nathan Sharon 《Glycoconjugate journal》1987,4(4):379-390
The interaction of125I-labeledErythrina cristagalli agglutinin (ECA) with neutral glycosphingolipids on thin layer chromatograms was examined by the overlay technique followed by radioautography. The lectin bound topara-globoside with a sensitivity about 10 times higher than to lactosylceramide or globoside, in agreement with the specificity of the lectin forN-acetyllactosamine. The lower limit of detection ofpara-globoside was about 0.66 nmol. The specific binding of ECA to this glycolipid was confirmed by a highly sensitive enzyme-linked lectin assay (ELLA), utilizing the horseradish peroxidase-avidin-biotin system for detection of bound lectin. Overlays of neutral glycosphingolipid extracts from human erythrocyte membranes and from human granulocytes with ECA demonstrated that the lectin can be employed for the detection of small amounts ofpara-globoside in biological materials also in the presence of excess globoside. No staining was obtained when thin layer chromatograms of neutral glycosphingolipid extracts from rabbit erythrocyte membranes were overlayed with125I-ECA. Afterin situ treatment of the chromatograms with -galactosidase, the lectin bound to several components, one of which had a mobility corresponding to that of the pentahexosylceramide Gal3Gal4GlcNAc3Gal4Glc1Cer, the major neutral glycosphingolipid of rabbit erythrocytes, thus providing further evidence for the specificity of ECA forpara-globoside.Abbreviations GSL
glycosphingolipid(s)
- CDH
lactosylceramide, Gal4Glc1Cer
- CTH
trihexosylceramide, Gal4Gal4Glc1Cer
- GLOB
globoside, GalNac3Gal4Gal4Glc1Cer
- PG
para-globoside, Gal4GlcNAc3Gal4Glc1Cer
- AsGM1
asialo-GM1, Gal3GalNAc4Gal4Glc1Cer
- FORS
Forsmann antigen, GalNAc3GalNAc3Gal4Gal4Glc1Cer
- CPH
pentahexosylceramide, Gal3Gal4GlcNAc3Gal4Glc1Cer
- ECA
Erythrina cristagalli agglutinin
- SBA
soybean agglutinin
- PBS
phosphate-buffered saline
- PVP-40
polyvinylpyrrolidone M.W. 40000
- BSA
bovine serum albumin
- HRP-avidin
horseradish peroxidase conjugated to avidin
- ELLA
enzyme-linked lectin assay
- ELISA
enzyme-linked immunosorbent assay
- PMNL
polymorphonuclear leukocytes
- HPTLC
high performance thin layer chromatography 相似文献
47.
F.S.F. Tanee D. Njamen C.B. Magne Nd J. Wanji O. Zierau Z.T. Fomum G. Vollmer 《Phytomedicine》2007,14(2-3):222-226
The stem bark of Erythrina lysistemon, one of the traditionally used "women remedies", has been assessed for its estrogenic activity. The ethyl-acetate extract of the stem bark of E. lysistemon showed estrogenic activities in vitro either in a yeast-based estrogen receptor assay or on the estrogen-dependent stimulation of alkaline phosphatase activity in the human endometrial carcinoma cell line Ishikawa. The estrogenic activity was investigated in vivo in young ovariectomized Wistar female rats after a 7-day treatment. The estrogenicity was evaluated through the proliferative status of target sex organs such as uterus and vagina. The results obtained showed that oral administration of 200 mg/kg BW/d of E. lysistemon extract in comparison to untreated ovariectomized rats significantly increased the vaginal epithelial height by 47.23% (from 8.71+/-0.47 to 12.34+/-1.31 microm); and induced a weak increase of uterine epithelial height by 6.76% (from 5.42+/-0.52 to 5.84+/-0.91 microm). Both were not as pronounced as those elicited in the positive control of 100 microg/kg BW/d of ethinylestradiol given orally. Overall our results suggest that the extract of E. lysistemon contains secondary metabolites endowed with estrogenic activity. 相似文献
48.
龙牙花不同花器官的表皮形态 总被引:1,自引:0,他引:1
花的光合作用与气孔密度密切相关, 但关于在花生长过程中气孔密度如何改变尚未见报道。以龙牙花(Erythrina corallodendron)花为实验材料, 将花的生长期分为6个阶段, 采用光学显微镜对不同阶段的花萼、旗瓣、翼瓣、龙骨瓣、雌蕊托、子房、花柱、花丝和花药表皮的形态特征、表皮细胞密度、气孔密度、保卫细胞长度及宽度进行研究, 并
对其光合作用的能力进行测定。结果发现: 除了翼瓣和花丝表皮以外, 气孔均分布在花朵的其它器官表皮上, 如花萼、旗瓣、龙骨瓣、雌蕊托、子房、花柱和花药。气孔复合体主要有无规则型、平列型以及辐射型, 但不同花器官存在的气孔类型具有差异。在花萼、旗瓣、龙骨瓣、翼瓣以及花丝生长过程中表皮细胞密度逐步下降, 表明其生长主要由表皮细胞扩大引起;大部分花器官如花萼、旗瓣、龙骨瓣、雌蕊托和子房表皮的气孔密度在其生长中后期趋于稳定, 然而其保卫细胞长度和宽度的变化规律具有多样性。旗瓣不进行光合作用。 相似文献
49.
三种台湾景观树的引种栽培及在公路绿化中的应用 总被引:1,自引:1,他引:0
本文介绍从台湾省引进的鸡冠刺桐、罗比梅、黄金串钱柳的生物学特征、栽培要点及在厦门公路景观绿化中的应用。 相似文献
50.
C. Saito N. Nagata A. Sakai K. Mori H. Kuroiwa T. Kuroiwa 《Sexual plant reproduction》2000,12(5):296-301
The generative cell at anthesis in the mature pollen grain of Erythrina crista-galli (Fabaceae) was examined by 4,6-diamidino-2-phenylindole(DAPI)-fluorescence microscopy using the squash method. An unequal,
polarized distribution of DNA-containing organelles (plastids and/or mitochondria) within the generative cell was observed
in every mature pollen grain examined. Polarization of DNA-containing organelles is obvious when generative cells are freed
and assume a spherical shape soon after microspore mitosis, as revealed by fluorescence-microscopic observations of specimens
embedded in Technovit 7100 resin and thin-sectioned at different developmental stages. Early establishment of polarized localization
of organelles in young generative cells of E. crista-galli and maintenance of this unequal distribution until pollen maturation strongly suggests that the organelles may still be clustered
at pollen mitosis. Production of a dimorphic pair of sperm cells, as has been reported in Plumbago
zeylanica, was observed in some pollen tubes germinated in vitro. The differentiation of the two sperm cells is discussed in relation
to possible preferential double fertilization in angiosperms.
Received: 28 July 1999 / Revision accepted: 8 November 1999 相似文献