Preparation And Evaluation Of Modified Total Alkaloid Fraction From Nux Vomica

In this paper,the extraction of the total alkaloid fraction(TAF)was optimized.To remove the most toxic ingredient-strychnine from TAF,one-step precipitation method was used and the process was we investigated to prepare the modified total alkaloid fraction(MTAF).A sensitive and specific HPLC method was established to determine the ingredients in TAF and MTAF.In contrast to TAF,the ratio of brucine to strychnine was adjusted from 1:1.8 to 3.07:1 in MTAF.Strychnine was removed by optimization to a great extent,about 86%while the transfer ratio of brucine was 75%.Also a TOF-MS system was used to identify the chemical constituents of the MTAF and the TAF,and same components were identified in the MTAF and TAFR At the same time,the trend of toxicity diversity between the MTAF and the TAF was explored through acute toxicity experiment of mice.The acute toxicity results show that the LD50 of the MTAF is 31.08 mg/kg,the LD50 of the TAF is 10.92 mg/kg.The toxicity of the MTAF equals about 3 times of the TAF.In order to predict the oral absorption effect of MTAF,oil-water partition coefficient of the mixture of strychnine and brucine in different proportion was examined.The results show that when the proportion of strychnine and brucine was higher than 3:1,the oil-water partition coefficient of strychnine increased significantly.It displayed if further reduced strychnine of MTAF,the proportion of the oral absorption of its was likely to increase.The analgesic efficacy and anti-tumor effect of TAF and MTAF was compared.The inhibitory effect to HT1080 cells was compared,then explored their mechanism.Results shown that the inhibition of MTAF was stronger than TAF.The result showed the MTAF had stronger inhibitory to cells.Also,both of TAF and MTAF could effectively induce apoptosis of tumor cells.The analgesic effect of TAF and MTAF was compared by hot plate in mice.The results showed both of them had strong analgesic effect,MTAF exhibited stronger effect.The HPLC method was optimized to determining brucine plasma concentration and apply the method for the investigation on pharmacokinetics of brucine.The oil-water partition coefficient and the rat plasma protein binding rate of brucine-N-oxide were determined for the first time.A rapid and sensitive liquid chromatography tandem mass spectrometry(LC-MS-MS)method has been developed and validated for the quantitative determination of brucine-N-oxide in rat plasma.The validated method has been successfully applied to determine the pharmacokinetic profile of brucine-N-oxide in rat plasma following oral and i.v.administration at a dose of 40 mg/kg.Based on the AUC0-? obtained from oral and i.v.administration,the absolute bioavailability(F)of brucine-N-oxide was estimated as 41.30%.The pharmacokinetic properties of MTAF after oral in SD rats were explored.A sensitive,specific LC-MS-MS method was developed for the analysis of brucine,strychnine and brucine-N-oxide in SD rat plasma.In oral group,the AUC0?t of brucine was 2.4 times higher than strychnine,66 times than brucine-N-oxide,while MRT0?t was 2.1 times higher than strychnine.The MRT0?t of brucine-N-oxide was 1.2 times higher than brucine?2.1 times than strychnine.