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381.
382.
Melanoma is the most aggressive and lethal type of skin cancer, characterized by therapeutic resistance. In this context, the present study aimed to investigate the cytotoxic potential of manool, a diterpene from Salvia officinalis L., in human (A375) and murine (B16F10) melanoma cell lines. The analysis of cytotoxicity using the XTT assay showed the lowest IC50 after 48 h of treatment with the manool, being 17.6 and 18.2 µg/ml for A375 and B16F10, respectively. A selective antiproliferative effect of manool was observed on the A375 cells based on the colony formation assay, showing an IC50 equivalent to 5.6 µg/ml. The manool treatments led to 43.5% inhibition of the A375 cell migration at a concentration of 5.0 µg/ml. However, it did not affect cell migration in the B16F10 cells. Cell cycle analysis revealed that the manool interfered in the cell cycle of the A375 cells, blocking the G2/M phase. No changes in the cell cycle were observed in the B16F10 cells. Interestingly, manool did not induce apoptosis in the A375 cells, but apoptosis was observed after treatment of the B16F10 cells. Additionally, manool showed an antimelanoma effect in a reconstructed human skin model. Furthermore, in silico studies, showed that manool is stabilized in the active sites of the tubulin dimer with comparable energy concerning taxol, indicating that both structures can inhibit the proliferation of cancer cells. Altogether, it is concluded that manool, through the modulation of the cell cycle, presents a selective antiproliferative activity and a potential antimelanoma effect.  相似文献   
383.
Salvia L.(family Lamiaceae),a large genus of over 1000 species,is widely distributed throughout tropical and temperate regions of the world.Eight-four species are native to China.However,there are many taxonomic uncertainties at the sub-generic level.Diterpenoids are a class of secondary metabolites with a large variety of structures that have been used as chemotaxonomic markers at infra-and suprageneric levels.For the sake of further chemotaxonomic understanding of Salvia,the present study investigated the...  相似文献   
384.
Hairy root cultures of Salvia miltiorrhiza were established by infecting sterile plantlets with Agrobacterium rhizogenes ATCC 15834, and the transformation was proved by direct detection of the inserted T-DNA by the polymerase chain reaction. As determined by HPLC, these hairy root cultures had the ability to produce lithospermic acid B (LAB), rosmarinic acid (RA) and other related phenolic compounds, the water-soluble active components of the plant. The effect of five different basal media, MS, MS-NH<INF>4</INF> (MS without ammonium nitrate), B5, WPM and 6,7-V on the root growth and phenolic compound production was studied. It was found that MS-NH<INF>4</INF> and 6,7-V media were superior to MS, B5 and WPM media in terms of both root growth and phenolic compound production. The time course of biomass accumulation and phenolic compound formation was also examined in the culture using MS-NH<INF>4</INF>medium. During cultivation, the content of RA in the roots was stable being approximately 0.48% of dry weight while the content of LAB fluctuated between 0.73% and 1.61% of dry weight, and decreased gradually at the stationary phase of growth. The highest production of LAB and RA was about 64 mg L−1 and 23 mg L−1, respectively. Received 05 November 1998/ Accepted in revised form 06 February 1999  相似文献   
385.
386.
Contrary to most other bee species honeybees are highly eusocial and hold extremely long-lived societies. Their all-season activities force them to use whatever plants available and prevent any specific adaptations — in the flowers, in honeybees, and in all competing bees. This flexible behaviour in flowers has been a precondition for perennial colony life. But as bees evade becoming contaminated by pollen their visits often do not result in pollination. Honeybee monocultures thus must be avoided by all means.  相似文献   
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