Showing papers on "Gentiana published in 2006"

Effects of Gentiopicroside, Sweroside and Swertiamarine, Secoiridoids from Gentian (Gentiana lutea ssp. symphyandra), on Cultured Chicken Embryonic Fibroblasts

Abstract: Wound healing properties of Gentian (Gentiana lutea ssp. symphyandra) extract and its main constituents, gentiopicroside, sweroside and swertiamarine (compounds 1-3, respectively) were evaluated by comparison with dexpanthenol on cultured chicken embryonic fibroblasts. The extract was also analyzed by HPLC to quantify its constituents. Chicken embryonic fibroblasts from fertilized eggs were incubated with the plant extract and its constituents, compounds 1-3. Using microscopy, mitotic ability, morphological changes and collagen production in the cultured fibroblasts were evaluated as parameters. Wound healing activity of Gentian seems to be mainly due to the increase in the stimulation of collagen production and the mitotic activity by compounds 2 and 3, respectively (p < 0.005 in all cases). All three compounds also exhibited cytoprotective effects, which may cause a synergism in terms of wound healing activity of Gentian. The findings demonstrated the wound healing activity of Gentian, which has previously been based only on ethnomedical data.

Two different transposable elements inserted in flavonoid 3′,5′-hydroxylase gene contribute to pink flower coloration in Gentiana scabra

Abstract: Pink-flowered gentian plants (Gentiana scabra) have been bred from spontaneous mutations of blue-flowered gentian plants, but the formation mechanism(s) is unknown so far. To investigate the process, two independent pink-flowered gentian plant lines were analyzed by a molecular biological approach. HPLC analysis showed that petals of the blue-flowered cultivar contained a small amount of cyanidin derivatives and major delphinidin derivatives, whereas pink petals had only a small amount of cyanidin derivatives. To find the causal factor(s) of this change, we focused on flavonoid 3',5'-hydroxylase (F3',5'H), which is a key enzyme for delphinidin biosynthesis in the flavonoid biosynthetic pathway. Molecular analyses confirmed that the loss of delphinidin synthesis could be attributed to the insertions of different transposable elements in the F3',5'H gene in each independent pink-flowered gentian plant. Sequence analysis showed that these transposable elements were classified into an hAT superfamily and terminal-repeat retrotransposon in miniature (TRIM), by which normal F3',5'H transcripts were interrupted. Southern blot analysis indicated that they belong to high copy number elements and are also found in a related gentian species (G. triflora). These results suggest that the transposable elements inserted in F3',5'H are the source of the mutations and may also play a substantial role in the genomic evolution of the genus Gentiana.

Free radical scavenging activities of yellow gentian (Gentiana lutea L.) measured by electron spin resonance.

Abstract: Yellow gentian (Gentiana lutea L.) is a herbal species with a long-term use in traditional medicine due to its digestive and stomachic properties. This paper presents an investigation of the free radical scavenging activity of methanolic extracts of yellow gentian leaves and roots in two different systems using electron spin resonance (ESR) spectrometry. Assays were based on the stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) and the superoxide radicals (O2*-) generated by the xanthine/xanthine oxidase (X/XO) system. The results of gentian methanolic extracts were compared with the antioxidant capacity of synthetic antioxidant butylated hydroxyanisole (BHA). This study proves that yellow gentian leaves and roots exhibit considerable antioxidant properties, expressed either by their capability to scavenge DPPH or superoxide radicals.

Antiproliferative activity of root extract from gentian plant (Gentiana triflora) on cultured and implanted tumor cells.

Abstract: We describe a novel pharmacological activity of the gentian root, an ingredient of Chinese medicines. Root extract from Gentiana triflora triggered cell death of human Daudi cells in culture. In addition, daily administration of the extract to mice inhibited growth of implanted solid tumors. Extract treatment of cultured cells resulted in the appearance of shranken, fragmented, or condensed cell and nuclear morphologies, and in chromosomal DNA degradation. But, the extract-treated cells did not show DNA fragmentation, which exhibits a nucleosome ladder, suggesting that extract-triggered cell death is not mediated through a typical apoptotic pathway.

Nastic corolla movements of nine Gentiana species (Gentianaceae), presented in the Bulgarian flora

Abstract: The corolla movements promote partial self-pollination in the perennial Gentiana pneumonanthe, G. cruciata and G. pyrenaica, as well as in the annual G. utriculosa and G. nivalis. There is a threshold flower temperature for opening/closing movements. Both the infrared and ultraviolet rays are of importance for flower closure. The flowers of some gentians - the homogamous G. verna, G. utriculosa and G. nivalis - gradually lose their extremely high sensitivity during their lifespan. The flowers of protogynous G. punctata also lose their flower sensitivity. Flower sensitivity does not correlate with flower age in the strongly protandrous G. cruciata and G. pyrenaica.