Objective: To establish a method for identifying cardiac glycosides in Scurrula parasitica and its Nerium indicum host by UPLC-Q-TOF-MS/MS. With safflower parasitoids with sweet-scented osmanthus trees as the host and their host osmanthus tree samples used for control, the chemical constituents of the cardiac glycosides were identified by comparison between the cardiac glycoside reference substances and literatures, so as to analyze the correlation between the safflower parasitoid and its host oleander glycoside components,and evaluate the host' s impact on the quality of Taxilli Herba. Method: Samples of S. parasitica (parasitic on N. indicum and Osmanthus fragrans),N. indicum and O. fragrans were collected. Samples of S. parasitica and its O. fragrans host were taken for control. All of the samples were extracted through ultrasonic extraction with 70%ethanol. ACQUITY UPLC HSS T3 C₁₈(2.1 mm×100 mm,1.8 μm) column was adopted with mobile phase A comprising 0.1%formic acid water and mobile phase B comprising acetonitrile for gradient elution. The sample size was 0.5 μL. The flow rate was 0.6 mL·min^-1. The column temperature was maintained at 40℃. MassLynx V4.1 software was used to analyze the data. Identification and correlation of chemical constitute of cardiac glycosides in S. parasitica and its N. indicum host were performed through analysis on cardiac glycosides reference substances,relevant literatures,elemental composition of compounds and positive and negative ion mode mass spectrometry data. Result: A total of 26 compounds of cardiac glycoside were identified,including 25 compounds of cardiac glycoside from N. indicum host,and 5 compounds of cardiac glycoside from S. parasitic(parasitic on N. indicum). none of cardiac glycosides were found in S. parasitica (parasitic on O. fragrans ) and its O. fragrans host. Conclusion: It was rapid,accurate and comprehensive to identify cardiac glycosides in S. parasitica (parasitic on N. indicum) and its N. indicum host by UPLC-Q-TOF-MS/MS. S. parasitica itself does not contain cardiac glycosides,its host may impact the quality of S. parasitica by delivering cardiac glycosides, a kind of its characteristic compound.

Objective:To explore the acute toxicities and hepatotoxicities of aqueous extracts of Taxilli Herba from Morus alba， Toxicodendron trichocarpum， Camellia oleifera， Salix babylonica， Melia azedarach， and Nerium indicum against zebrafish model and the effect of different hosts on the toxicity of Taxilli Herba， hoping to provide a theoretical basis for the safe use of Taxilli Herba. Method:The normally developed AB zebrafish at 3-day post fertilization was selected for acute toxicity study. According to the results of preliminary toxicity experiments， the zebrafishes were treated with aqueous extracts of Taxilli Herba from different hosts at six doses， and their mortality was calculated 72 h later. GraphPad Prism 6.0 was used for plotting the dose-toxicity curve， followed by the calculation of their median lethal concentration （LC₅₀） and 10% lethal concentration （LC₁₀）. The gz15Tg/+（AB） liver fluorescent protein transgenic zebrafish with normal development at 4-day post fertilization was applied for the hepatotoxicity study. The zebrafishes were divided into the low-， medium-， and high-dose groups of aqueous extracts of Taxilli Herba from six hosts， the positive control （acetaminophen） group， and the blank （embryo amniotic fluid） group， and then treated with the corresponding drugs. Seventy-two hours later， the liver morphology and fluorescent area changes in zebrafish were observed. And the activities of alanine aminotransferase （ALT） and aspartate aminotransferase （AST） were detected. Result:The results of acute toxicity test demonstrated that the LC₅₀ values of water extracts of Taxilli Herba from M. alba， T. trichocarpum， C. oleifera， S. babylonica， M. azedarach， and N. indicum were 1.24， 0.94， 0.51， 0.38， 0.11， 0.09 g·L^-1， respectively， and the LC₁₀ values were 0.70， 0.60， 0.35， 0.28， 0.08， 0.07 g·L^-1， respectively. As revealed by hepatotoxicity test， compared with the blank group， the positive control group exhibited liver morphological changes， decreased fluorescent area （P<0.01）， and elevated ALT and AST activities （P< 0.01）， suggesting that acetaminophen was hepatotoxic to zebrafish. However， there was no change in the liver morphology or fluorescent area of zebrafish in the low-， medium-， and high-dose groups of water extracts of Taxilli Herba from M. alba， and the ALT and AST activities were decreased. By contrast， the liver morphology and fluorescent areas in the medium- and high-dose groups of water extracts of Taxilli Herba from T. trichocarpum， C. oleifera， S. babylonica， M. azedarach， and N. indicum changed to varying degrees （P<0.05， P<0.01）. Besides， the activities of both ALT and AST were also enhanced. These indicated that Taxilli Herba from M. alba had no hepatotoxicity to zebrafish， while that from T. trichocarpum， C. oleifera， S. babylonica， M. azedarach， and N. indicum showed varying degrees of hepatotoxicity to zebrafish. Conclusion:The toxicity of Taxilli Herba is host-dependent. Taxilli Herba from M. alba has no hepatotoxicity， but that from the other five hosts shows varying degrees of hepatotoxicity. Standardizing the host source may be an important measure to realize the medication safety of Taxilli Herba.