Crinamine from Crinum asiaticum var. japonicum inhibits hypoxia inducible factor-1 activity but not activity of hypoxia inducible factor-2. (1/5)

In a search for natural product inhibitors of hypoxia inducible factor-1 (HIF-1) function, crinamine (1), a crinane type alkaloid, showed potent dose dependent inhibition (IC50 = 2.7 microM) of HIF-1alpha in a cell-based reporter gene assay. Crinamine (1) was isolated from the aerial parts of Crinum asiaticum var. japonicum together with lycorine (2), norgalanthamine (3) and epinorgalanthamine (4). The other components (2-4) showed no significant inhibition of HIF-1alpha induced transcriptional activity.  (+info)

Antibacterial agents from the leaves of Crinum purpurascens herb (Amaryllidaceae). (2/5)

BACKGROUND: Typhoid fevers and urogenital infections continue to be serious health problems in developing countries. In our search for therapeutic agents from natural sources with potential for the treatment of typhoid fevers and urogenital infections, extract and compounds were obtained from Crinum purpurascens and tested. METHODS: Two alkaloids (4,5-ethano-9,10-methylenedioxy-7-phenanthridone or hippadine (1) and 4,5-ethano-9-hydroxy-10-methoxy-7-phenanthridone or pratorimine (2)) and one steroid (a-D-glucopyranoside of sitosterol (3)) were isolated from the CH(2)Cl(2)/MeOH (1:1) leaf extract of Crinum purpurascens and screened for antibacterial activity using both agar diffusion and broth dilution techniques. RESULTS: For the CH(2)Cl(2)/MeOH extract, the MIC values obtained were 3 mg/ml (against P. aeruginosa), 4 mg/ml (against E. coli, K. pneumoniae and S. aureus) and 6 mg/ml (against S. typhi and S. paratyphi B), whereas the MBC values varied between 7 and 12 mg/ml. For compound 1, the MIC values varied between 200 and 250 microg/ml, whereas the MBC value was 300 microg/ml against all the bacteria strains used. Compound 2 did not show any antimicrobial activity against these bacteria strains. For compound 3, the MIC values varied between 250 and 300 microg/ml, whereas the MBC values were 300 microg/ml (against S. typhi and S. paratyphi B) and > 300 microg/ml (against the other bacteria strains). CONCLUSION: These data suggest that C. purpurascens leaf extract contains antibacterial agents which could be used in the treatment of typhoid fevers and urogenital infections.  (+info)

Two new alkaloids from Crinum asiaticum var. sinicum. (3/5)

Two new alkaloids (1, 2) were isolated from the whole plants of Crinum asiaticum var. sinicum together with seven known alkaloids. The structures of the new alkaloids were elucidated by spectroscopic analyses and chemical conversions from known alkaloids. New alkaloid 1 was isolated for the first time as a natural product, although it has been prepared as a synthetic product.  (+info)

Crystallization and preliminary X-ray analysis of crinumin, a chymotrypsin-like glycosylated serine protease with thrombolytic and antiplatelet activity. (4/5)

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Effect of four medicinal plants on amyloid-beta induced neurotoxicity in SH-SY5Y cells. (5/5)

Amyloid-beta peptide (Abeta) is implicated in the pathogenesis of Alzheimer's disease (AD), a neurodegenerative disorder. This study was designed to determine the effect of four medicinal plants used to treat neurodegenerative diseases on Abeta-induced cell death. Cytotoxicity of the ethanol extracts of the plants was determined against SH-SY5Y (human neuroblastoma) cells which were untreated, as well as toxically induced with Abeta, using the MTT and neutral red uptake assays. Cell viability was reduced to 16% when exposed to 20 microM Abeta25-35 for 72 h. The methanol extract of the roots of Ziziphus mucronata Willd., Lannea schweinfurthii (Engl.) Engl. and Terminalia sericea Burch. ex DC., were the least toxic to the SH-SY5Ycells at the highest concentration tested (100 microg/ml). All four plants tested were observed to reduce the effects of Abeta-induced neuronal cell death, indicating that they may contain compounds which may be relevant in the prevention of AD progression.  (+info)