Fifteen known amaryllidaceae alkaloids were isolated from the bulbs of Lycoris radiata.Some of the compounds and lycoricidine derivatives had been screened for the activities against tobacco mosaic virus(TMV)by the co...Fifteen known amaryllidaceae alkaloids were isolated from the bulbs of Lycoris radiata.Some of the compounds and lycoricidine derivatives had been screened for the activities against tobacco mosaic virus(TMV)by the conventional halfleaf method.Lycoricidine derivatives were also carried out the assay of effect on systemic infection of TMV by western-blot and RT-PCR analysis.The tested compounds showed moderate inactivation effect,whereas the lycoricidine derivatives showed good protective effect.The protective inhibitory activity of compounds L1(N-methyl-2,3,4-trimethoxyly-coricidine)(60.8%)and L3(N-methyl-2-methoxy-3,4-acetonidelycoricidine)(62.0%)was almost similar to the positive control,Ningnanmycin(66.4%).RT-PCR and Western-blot analysis displayed that compounds L1,L3,L5(N-allyl-2,3,4-triallyloxylycoricidine)exhibited antiviral activity,which was evidenced by reducing TMV-CP gene replication and TMV-CP protein expression.Additionally,defensive enzyme activities confirmed that compound L1 could increase the activity of PAL,POD,SOD to improve disease resistance of tobacco.展开更多
A rapid, sensitive, and selective liquid chromatography-tandem mass spectrometry was developed for the simultaneous determination of lycorine and galanthamine, two major constituents in Lycoris radiata extract, in rat...A rapid, sensitive, and selective liquid chromatography-tandem mass spectrometry was developed for the simultaneous determination of lycorine and galanthamine, two major constituents in Lycoris radiata extract, in rat plasma. Liquid-liquid extraction with ethyl ether was carried out using diphenhydramine as the internal standard The two bioactive alkaloids were separated on a Zorbax SB-C18 reserved-phase column （150 mm× 4.6 mm, i.d., 5 μm） by gradient elution using a mobile phase consisting of methanol with 0.1% formic acid （A） and water with 0.1% formic acid （B） at a flow rate of 0.6 mL/min. All analytes showed good linearity over a wide concentration range （r^2〉0.99） and the lower limit of quantification was 3.00 ng/mL for each analyte. The average extraction re- covery of the analytes from rat plasma was more than 82.15%, and the intra-day and inter-day accuracy and preci- sion of the assay were less than 12.6%. The validated method was successfully applied to monitoring the concen- trations and pharmacokinetic studies of two Amaryllidaceous alkaloids in rat plasma after an oral administration of Lycoris radiata extract.展开更多
Lycoris radiata mannose-binding lectin（LRL） is a protein which binds mannose residues specifically. The maturation peptide and three mannose-binding domains（residues 49-57, 80-88 and 113--121） of LRL were identifi...Lycoris radiata mannose-binding lectin（LRL） is a protein which binds mannose residues specifically. The maturation peptide and three mannose-binding domains（residues 49-57, 80-88 and 113--121） of LRL were identified by sequence analysis. The 3D structure of LRL constructed by homology modeling shaped a flstular triangular prism. Three flanks of the prism are mainly composed of β-sheets and each flank has a mannose-binding domain. According to the docking and dynamics simulation, the bindings of residues 49--57 and 80--88 with mannose are more stable than that of residues 113--121 with it. The key residues for binding mannose are Gin80, Asp82, Ash84 and Tyr88. The study preliminarily analyzed the interaction sites and mechanism of LRL with mannoses, which could be useful for the study on insect-resistance and related drug discovery of LRL.展开更多
基金the National Natural Science.Foundation of China(Nos.31770389,31470427,31270404).
文摘Fifteen known amaryllidaceae alkaloids were isolated from the bulbs of Lycoris radiata.Some of the compounds and lycoricidine derivatives had been screened for the activities against tobacco mosaic virus(TMV)by the conventional halfleaf method.Lycoricidine derivatives were also carried out the assay of effect on systemic infection of TMV by western-blot and RT-PCR analysis.The tested compounds showed moderate inactivation effect,whereas the lycoricidine derivatives showed good protective effect.The protective inhibitory activity of compounds L1(N-methyl-2,3,4-trimethoxyly-coricidine)(60.8%)and L3(N-methyl-2-methoxy-3,4-acetonidelycoricidine)(62.0%)was almost similar to the positive control,Ningnanmycin(66.4%).RT-PCR and Western-blot analysis displayed that compounds L1,L3,L5(N-allyl-2,3,4-triallyloxylycoricidine)exhibited antiviral activity,which was evidenced by reducing TMV-CP gene replication and TMV-CP protein expression.Additionally,defensive enzyme activities confirmed that compound L1 could increase the activity of PAL,POD,SOD to improve disease resistance of tobacco.
基金supported by the Natural Science Foundation of Fujian Province of China(No.2013J01382)
文摘A rapid, sensitive, and selective liquid chromatography-tandem mass spectrometry was developed for the simultaneous determination of lycorine and galanthamine, two major constituents in Lycoris radiata extract, in rat plasma. Liquid-liquid extraction with ethyl ether was carried out using diphenhydramine as the internal standard The two bioactive alkaloids were separated on a Zorbax SB-C18 reserved-phase column （150 mm× 4.6 mm, i.d., 5 μm） by gradient elution using a mobile phase consisting of methanol with 0.1% formic acid （A） and water with 0.1% formic acid （B） at a flow rate of 0.6 mL/min. All analytes showed good linearity over a wide concentration range （r^2〉0.99） and the lower limit of quantification was 3.00 ng/mL for each analyte. The average extraction re- covery of the analytes from rat plasma was more than 82.15%, and the intra-day and inter-day accuracy and preci- sion of the assay were less than 12.6%. The validated method was successfully applied to monitoring the concen- trations and pharmacokinetic studies of two Amaryllidaceous alkaloids in rat plasma after an oral administration of Lycoris radiata extract.
文摘Lycoris radiata mannose-binding lectin（LRL） is a protein which binds mannose residues specifically. The maturation peptide and three mannose-binding domains（residues 49-57, 80-88 and 113--121） of LRL were identified by sequence analysis. The 3D structure of LRL constructed by homology modeling shaped a flstular triangular prism. Three flanks of the prism are mainly composed of β-sheets and each flank has a mannose-binding domain. According to the docking and dynamics simulation, the bindings of residues 49--57 and 80--88 with mannose are more stable than that of residues 113--121 with it. The key residues for binding mannose are Gin80, Asp82, Ash84 and Tyr88. The study preliminarily analyzed the interaction sites and mechanism of LRL with mannoses, which could be useful for the study on insect-resistance and related drug discovery of LRL.
