Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0277787 (stigma)
 13,352 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A new triterpene saponin and known steroidal glucoside were isolated from the alcohol extract, and a new cycloartenol from n-hexane extract of seeds of Nigella sativa L. and were identified as 3-O-[beta-D-xylopyranosyl-(1-->2)-alpha-L-rhamnopyranosyl-(1 --> 2)-beta-D-glucopyranosyl]-11-methoxy-16,23-dihydroxy-28-methylolean-12-enoate (1), stigma-5,22-dien-3-beta-D-glucopyranoside (2) and cycloart-23-methyl-7,20, 22-triene-3beta,25-diol (3), respectively. They were characterised on the basis of spectral analysis and comparison with literature data. The hexane and alcohol extract of the seeds showed antimicrobial activity. The antioxidant activity of hexane extract is also described.
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PMID:New principles from seeds of Nigella sativa. 1917 22

Preparative high-speed countercurrent chromatography (HSCCC) has been successfully used for the isolation and purification of isorhamnetin from Stigma maydis. This was achieved in two stages: the first separation was performed with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (HEMW) at a volume ratio of 5:5:5:5, yielding isorhamnetinat 65.6 %, which is followed by the second run using a two-phase solvent system composed of HEMW 5:5:6:4, v/v. From 700 mg of the crude extract 11.8 mg of isorhamnetin was obtained at a high purity of 98%. The final identification was performed by MS, (1)H-NMR and (13)C-NMR spectra.
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PMID:PREPARATIVE ISOLATION OF ISORHAMNETIN FROM STIGMA MAYDIS USING HIGH-SPEED COUNTERCURRENT CHROMATOGRAPHY. 2004 59

Pollen-stigma interactions were studied with scanning electron microscopy in intraspecific and intersectional crosses of Populus tremuloides (Sect. LEUCE); P. deltoides, P. nigra (Sect. AIGEIROS); and P. trichocarpa (Sect. TACAMAHACA). Intraspecific variation in hydration, size of hydrated pollen grains, and tube morphology is described. Exine sculpture in P. tremuloides was densely spinulate or scabrate, in P. trichocarpa densely reticulate, in the other species somewhat intermediate. In six of seven intersectional cross combinations pollen-tube behavior on the stigmatic surface at 5-22 hours after pollination was the same as in conspecific matings; in P. tremuloides x P. trichocarpa crosses, the percentage of twisted and bulging tubes was significantly higher. Irradiated mentor pollen did not affect pollentube behavior of adjacent incompatible pollen, but increased hybrid seedling production in interspecific crosses. By contrast, hexane treatment of pollen or stigma, and the spraying of catkins with gibberellic acid or naphtalene acetic acid were ineffective. The results are discussed in relation to several mechanisms presumed to be involved in restricting gene exchange among poplar species; and in relation to Hogenboom's (1973) incongruity concept.
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PMID:Interspecific crossability studies in poplars. 2430 5