In this study, a sensitive ultra-performance liquid chromatography-photodiode array coupled to quadruple time-of-flight mass (UPLC-PDA-Q/TOF-MS) method and a 1,1-diphenyl-2- picrylhydrazyl (DPPH)-based assay were used to determine the chemical constituents and screen the antioxidant activity profiles of the methanol extracts of different parts of cultivated Cistanche deserticola (C. deserticola). First, qualitative and quantitative chemical composition analyses of the different parts of cultivated C. deserticola were conducted. Obvious differences were observed between the chemical profiles and content distribution of phenylethanoid glycosides (PhGs) from the different cultivated C. deserticola parts. The average contents of the six PhGs parts varied from 4.91 to 72.56 mg/g DW (milligrams of extract per gram of plant dry weight) in the six different parts of Cistanche deserticola, displaying a significant decreasing trend from the bottom to the top of cultivated C. deserticola and the highest content in the stems. From the bottom to the top of the plant, the echinacoside and cistanoside A content decreased and the 2 ${}^{\prime }$ -acetylacteoside content increased. Second, an offline DPPH assay revealed that the total scavenging activities of all parts within the range of 20–500 $\mathsf{\mu }$ g/mL increased in a concentration-dependent manner and that good antioxidant activities were found in all plant parts, particularly in the stems, which could be related to their higher PhG content. Additionally, a DPPH-UPLC-PDA method was successfully applied to rapidly screen the antioxidant profiles and antioxidant components of the different cultivated C. deserticola parts. According to the antioxidant profiles before and after the DPPH reaction, there were wide variations in the antioxidant activities of different cultivated C. deserticola parts. Moreover, the antioxidant profiles revealed the presence of major free radical scavengers identified as PhGs using UPLC-Q/TOF-MS. Finally, the established DPPH-UPLC-PDA method was reagent saving, rapid and feasible for correlating the chemical profile of traditional chinese medicines (TCMs) with their bioactivities without isolation and purification and may be used for multicomponent analysis of active substances in other foods and herbs. Therefore, to better harness C. deserticola resources, using this method to evaluate cultivated C. deserticola, a promising herb material with obvious antioxidant activity, is crucial.

Dehydrocorydaline (DHC), a quaternary alkaloid from Corydalis yanhusuo, has been demonstrated to be the active constituent in the treatment of coronary heart disease. In this study, a high-performance liquid chromatography–electrospray ionization–triple quadrupole linear ion trap mass spectrometry (HPLC–ESI–QTRAP MS) technique was used to identify DHC metabolites in plasma and bile after oral administration of DHC to rats. A total of 18 metabolites (M1 to M18) were identified and characterized by LC–MS/MS in the positive ion mode. These 18 metabolites were all present in rat bile, while only 9 were detected in plasma. O-demethylation, hydroxylation, di-hydroxylation, glucuronidation of O-demethyl DHC, sulfation of O-demethyl DHC and di-hydroxylation of dehydro-DHC were the major metabolic pathways of DHC. This is the first time that these metabolites of DHC have been identified in rat plasma and bile, which provides useful information for further analysis of the biotransformation of DHC and other quaternary protoberberine-type alkaloids.

Wen Luo Yin (WLY), a well-known traditional Chinese medicine formulation, has been used as a complementary therapy for the treatment of rheumatoid arthritis in clinical settings. However, the chemical constituents of WLY remain unclear. In this study, a high-performance liquid chromatography coupled with tandem mass spectrometry method was established to separate and comprehensively identify the chemical constituents of WLY. The analytes were eluted with a mobile phase of acetonitrile and 0.1% aqueous acetic acid. Mass detection was performed in both positive and negative ion mode. The MS/MS fragmentation pathways were proposed for the identification of the components. A total of 42 compounds including sesquiterpenes, alkaloids, biflavonoids, polyacetylenes, phenylpropanoids and acetylenic phenols were identified unambiguously or tentatively according to their retention times and mass behavior with those of authentic standards or literature data. The identification and structural elucidation of chemical constituents may provide important information for quality control and pharmacological research of WLY.

Shengjiang Xiexin decoction (SXD) exerts protective effects against gastrointestinal injury induced by irinotecan hydrochloride (CPT-11). The intestinal bacteria-associated in vitro pharmacokinetics of 16 components of SXD in normal rats and those with CPT-11-induced gastrointestinal toxicity were compared in this study. A sensitive and reproducible ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) method was developed for the quantification of 16 components of SXD in a rat intestinal bacteria incubation system, using naringin, naringenin and tetrahydropalmatine as internal standards (ISs). The samples were prepared via salting-out assisted liquid–liquid extraction (SALLE) with NaCl to reduce matrix effects. Chromatographic separation was performed on a sub-2 μm analytical column with acetonitrile and 0.1% aqueous formic acid as mobile phase. All of the analyzed components and ISs were detected via multiple reaction monitoring (MRM) scanning with electrospray ionization. The proposed method was successfully applied for the in vitro pharmacokinetic analysis of the multiple components of a complex mixture consisting of a traditional Chinese medicine (TCM) and an intestinal bacterial incubation system. The pharmacokinetic parameters of some flavonoid glycosides and aglycones in the rats with CPT-11-induced gastrointestinal toxicity were significantly different (p < 0.05, p < 0.01) from those in the normal rats, which suggested that consumption of CPT-11 could qualitatively and/or quantitatively alter the intestinal bacteria as well as the metabolic activities of enzymes. The in vitro pharmacokinetic analysis of these components in the intestinal bacterial incubation system provided valuable information for achieving a deeper understanding of the mechanisms involved in the alteration of intestinal bacteria induced by CPT-11 and further in vivo pharmacokinetic research on SXD. The intestinal bacteria-based pharmacokinetic method could benefit the study of interactions between TCMs and chemical drugs in clinical use.

Acetaminophen (APAP) overdose is very common worldwide and has been widely recognized as the leading cause of drug-induced liver injury in the Western world. In our previous investigation, auriculatone, a natural product firstly obtained from Aster auriculatus, has demonstrated a potent protective effect against APAP-induced hepatotoxicity in HL-7702 cells. However, the poor water solubility and low bioavailability restrict its application. Auriculatone sulfate (AS) is a sulfated derivative of auriculatone with highly improved water-solubility. Hepatoprotective effects against APAP-induced liver injury (AILI) showed that intragastric pretreatment with AS at 50 mg/kg almost completely prevented mice against APAP-induced increases of serum alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase and ATPase. Histological results showed that AS could protect the liver tissue damage. In addition, AS pretreatment not only significantly retained hepatic malondialdehyde and the activities of glutathione, superoxide dismutase, and glutathione peroxidase at normal levels, but also markedly suppressed the increase of pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 levels in mouse liver caused by overdose APAP. Immunohistochemical analysis showed that AS obviously attenuated the expression of CD45 and HNE in liver tissue. Further mechanisms of action investigation showed that inhibition of cytochrome P450 3A11 (CYP 3A11) and CYP2E1 enzymatic activities (but not that of CYP1A2) was responsible for APAP bioactivation. In conclusion, AS showed a hepatoprotective effect against AILI through alleviating oxidative stress and inflammation and inhibiting CYP-mediated APAP bioactivation. It may be an effective hepatoprotective agent for AILI and other forms of human liver disease.