Metabolites identification and reversible interconversion of chelerythrine and dihydrochelerythrine in vitro/in vivo in rats using ultra-performance liquid chromatography combined with electrospray ionization quadrupole time-of-flight tandem mass spectrometry

Identification of Sanguinarine Metabolites in Rats Using UPLC-Q-TOF-MS/MS

Sanguinarine (SAN), as the main active component of a traditional Chinese veterinary medicine, has been widely used in the animal husbandry and breeding industry. However, the metabolites of SA are still uncertain. Therefore, this research aimed to investigate the metabolites of SA based on rats in vivo. The blood, feces, and urine of rats were collected after the oral administration of 40 mg/kg SAN. Ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS) was employed to identify the metabolites of SAN. The elemental composition of sanguinarine metabolites was inferred by analyzing their exact molecular weight, and the structures of the metabolites were predicted based on their fragment ions and cleavage pathways. A total of 12 metabolites were identified, including three metabolites in the plasma, four in the urine, and nine in the feces. According to the possible metabolic pathways deduced in this study, SAN was mainly metabolized through reduction, oxidation, demethylation, hydroxylation, and glucuronidation. This present research has summarized the metabolism of SAN in rats, which is helpful for further studying the metabolic mechanism of SAN in vivo and in vitro.

Spectrum-Effect Relationship Analysis of Bioactive Compounds in Zanthoxylum nitidum (Roxb.) DC. by Ultra-High Performance Liquid Chromatography Mass Spectrometry Coupled With Comprehensive Filtering Approaches

Zanthoxylum nitidum (Roxb.) DC. (ZN), with strong effects of anti-inflammation and antioxidant activities is treated as a core herb in traditional Chinese medicine (TCM) preparation for treating stomachache, toothache, and rheumatoid arthritis. However, the active ingredients of ZN are not fully clarified due to its chemical complexity. In the present study, a double spectrum–effect analysis strategy was developed and applied to explore the bioactive components in herbs, and ZN was used as an example. Here, the chemical components in ZN were rapidly and comprehensively profiled based on the mass defect filtering-based structure classification (MDFSC) and diagnostic fragment-ion-based extension approaches. Furthermore, the fingerprints of 20 batches of ZN samples were analyzed by high-performance liquid chromatography, and the anti-inflammatory and antioxidant activities of the 20 batches of ZN samples were studied. Finally, the partial least squares regression (PLSR), gray relational analysis models, and Spearman’s rank correlation coefficient (SRCC) were applied to discover the bioactive compounds in ZN. As a result, a total of 48 compounds were identified or tentatively characterized in ZN, including 35 alkaloids, seven coumarins, three phenolic acids, two flavonoids, and one lignan. The results achieved by three prediction models indicated that peaks 4, 12, and 17 were the potential anti-inflammatory compounds in ZN, whereas peaks 3, 5, 7, 12, and 13 were involved in the antioxidant activity. Among them, peaks 4, 5, 7, and 12 were identified as nitidine, chelerythrine, hesperidin, and oxynitidine by comparison with the standards and other references. The data in the current study achieved by double spectrum–effect analysis strategy had great importance to improve the quality standardization of ZN, and the method might be an efficiency tool for the discovery of active components in a complex system, such as TCMs.

Biotransformation of alkylamides and alkaloids by lactic acid bacteria strains isolated from Zanthoxylum bungeanum meal

Zanthoxylum bungeanum meal (ZBM) is the by-product of Z. bungeanum seeds after pressing. It is restricted as a feed additive because it contains stimulating and potentially harmful substances, which are alkylamides and alkaloids. This study described the use of Lactobacillus paracasei and L. acidipiscis isolated from ZBM in solid-state fermentation of ZBM to reduce the concentration of undesirable alkylamides and alkaloids. By optimizing the substrate and fermentation conditions, the minimum contents of alkylamide and alkaloid were 2.96 and 3.20 mg/g, and the degradation rates reached 51.86% and 39.59%, respectively. Moreover, the biotransformation pathways of hydroxyl-α-sanshool and chelerythrine were established by identifying the metabolites. Bacterial diversity was shift significantly, and the relative abundance of Lactobacillus increased from 0.10% to 99.0% after fermentation. In conclusion, this study introduced a reliable strategy for processing ZBM as a feed additive.

Pharmacokinetics of Chelerythrine and Its Metabolite after Oral and Intramuscular Administrations in Pigs

The objective of this study was to investigate the single- and multiple-dose pharmacokinetics of chelerythrine (CHE) and its metabolite, dihydrochelerythrine (DHCHE), after oral and IM administrations in pigs.Six crossbreed (Landrace × Large White) female pigs (7 to 8 weeks old; 24.1 ± 2.6 kg bw) administered oral and IM CHE at a dose of 0.1 mg/kg orally and intramuscularly in a cross-over design. Multiple oral administration was performed at 0.1 mg/kg a time, three times a day at 8-h intervals for three consecutive days. Blood samples were collected from the anterior vena cava and placed into heparinized centrifuge tubes before dosing (time 0 h) and at different times after oral oral and IM administrations. Pretreatment plasma was analyzed by high-performance liquid chromatography tandem mass spectrometry.After IM administration, CHE and DHCHE rapidly reached peak concentrations (C_max, 69.79 ± 15.41 and 3.47 ± 1.23 ng/ml) at 0.42 ± 0.13 and 0.33 ± 0.13 h, respectively. After single oral administration, CHE and DHCHE rapidly increased to reach C_max of 5.04 ± 1.00 and 1.21 ± 0.35 ng/ml at 1.83 ± 0.26 and 1.67 ± 0.26 h, respectively. The half-life (T_1/2) was 2.03 ± 0.26 and 2.56 ± 1.00 h for CHE and DHCHE, respectively. After multiple oral administration, the average steady-state concentrations (C_ss) of CHE and DHCHE were 2.51 ± 0.40 and 0.6 ± 0.06 ng/ml, respectively.CHE is metabolized rapidly after a single oral administration, multiple daily doses and long-term use of CHE are recommended.