Determination of the Bioaccessibility of Cadmium in Golden Thread by Physiologically Based Extraction Test Digestion Using the in vitro/Caco2 Cell Model and Subsequent Risk Assessment

Background:The ingestion of golden thread contaminated with heavy metals through the food chain leads to detrimental effects to human health.During digestion,not all of the heavy metals could be released to the gastrointestinal tract and readily to be absorbed by human body.Thus,bioaccessibility is an important issue in health risk assessments.Aims and Objectives:The aims and objectives of this study were to investigate the bioaccessibility of Cd in golden thread and assess the associated health risks based on the exposure to bioaccessible Cd.Materials and Methods:Inductively coupled plasma mass spectrometry(ICP-MS)has been applied to determine the Cd content in golden thread.Physiologically based extraction test(PBET)digestion was performed in the in vitro/Caco2 cell model to investigate the bioaccessibility of Cd in golden thread.Furthermore,the target hazard quotient(THQ)was used to assess the risks of the total and the bioaccessible content of Cd in golden thread.Results:The results revealed that the total Cd content in six batches of golden thread ranged from 3.203 to 5.723 mg/kg.After uptake by Caco2 cells,the bioaccessibility of Cd ranged from 42.36%to 59.73%.The results of the risk assessment indicated that prior to uptake by Caco2 cells,the THQ values of Cd for all batches of golden thread were greater than 1.However,after uptake by Caco2 cells,the THQ values of Cd in all samples were less than 1,thus suggesting that the risks were at a safe level.Conclusion:This study was the first to perform health risk assessment with bioaccessible heavy metals present in traditional Chinese medicine by PBET digestion using an in vitro/Caco2 cell model,thus enabling us to obtain more accurate and objective results while allowing us to avoid unnecessary government intervention and to establish more reasonable limit standards for heavy metals.

Ultra-High Performance Liquid Chromatography/Ion Mobility-Quadrupole Time-of-Flight Mass Spectrometry and Database-Driven Automatic Peak Annotation for the Rapid Profiling and Characterization of the Multicomponents from Stephaniae Tetrandrae Radix(Fang-Ji)

Objective:Quality control of traditional Chinese medicine(TCM)begins with the chemical basis elucidation.The root of Stephania tetrandra has long been utilized as an antirheumatic,analgesic,and diuretic TCM,Stephaniae Tetrandrae Radix(STR;Fang-Ji).Powerful analytical strategies enabling its multicomponent characterization is still rare.Methods:A rapid,reliable,and enhanced profiling approach,by ultra-high performance liquid chromatography coupled with ion mobility/quadrupole time-of-flight mass spectrometry(UHPLC/IM-QTOF-MS)and automatic peak annotation facilitated by computational matching of in-house library,was established and utilized to characterize the multicomponents from STR.A knockout strategy was utilized by automated valve switching to overcome the interference of predominant peaks.Results:Good chromatographic separation was achieved within 17 min on a reversed-phase BEH C18 column eluted with acetonitrile/0.1%ammonium hydroxide in water,while data-independent high-definition MS^(E)(HDMS^(E))in positive mode was applied to acquire the MS^(2)data by using a Vion TM IM-QTOF instrument,which in theory,could cover all the profiled precursor ions.An in-house library of 163 compounds was established and incorporated into the UNIFITM platform.By feat of these efforts,we were able to identify or tentatively characterize 76 alkaloids from the methanolic extract of STR,including 14 aporphine-type,four morphine-type,48 bisbenzylisoquinoline-type,seven tetrahydroprotoberberine-type,one protopine-type,one benzylisoquinoline-type,and one other.Four-dimensional information,such as the retention time,collision cross section(CCS),high-accuracy MS1 and MS2 data,for each component was provided.Conclusions:The systematic multicomponent characterization of STR was accomplished with high coverage,high degree of automation,and high reliability.