Development and validation of a UPLC–ELSD method for fast simultaneous determination of five bile acid derivatives in Calculus Bovis and its medicinal preparations

Characterization of Calculus bovis by principal component analysis assisted qHNMR profiling to distinguish nefarious frauds

A new approach is developed for the reliable classification of Calculus bovis along with the identification of willfully contaminated C. bovis species and the quantification of unclaimed adulterants. Guided by a principal component analysis, NMR data mining achieved a near-holistic chemical characterization of three types of authenticated C. bovis, including natural C. bovis (NCB), in vitro cultured C. bovis (Ivt-CCB), and artificial C. bovis (ACB). In addition, species-specific markers used for quality evaluation and species classification were confirmed. That is, the content of taurine in NCB is near negligible, while choline and hyodeoxycholic acid are characteristic for identifying Ivt-CCB and ACB, respectively. Besides, the peak shapes and chemical shifts of H₂-25 of glycocholic acid could assist in the recognition of the origins of C. bovis. Based on these discoveries, a set of commercial NCB samples, macroscopically identified as problematic species, was examined with deliberately added sugars and outliers discovered. Absolute quantification of the identified sugars was realized by qHNMR using a single, nonidentical internal calibrant (IC). This study represents the first systematic study of C. bovis metabolomics via an NMR-driven methodology, which advances the toolbox for quality control of TCM and provides a more definitive reference point for future chemical and biological studies of C. bovis as a valuable materia medica.

Quantification of Bile Acids in Traditional Animal Medicines and Their Preparations Using Ultra High-Performance Liquid Chromatography-Mass Spectrometry in the Multiple Reaction Monitoring Mode

An ultra-high-performance liquid chromatograph-triple quadrupole mass spectrometry has been established and validated for the simultaneous quantification of 15 bile acids in four traditional animal medicines and their preparations. The separations of bile acids were performed on an Agilent ZORBAX Eclipse XDB-C18 column (50 × 2.1 mm; 1.8 μm) with methanol-0.1% formic acid as the mobile phase. Glycyrrhetinic acid was added as internal standard owing to its similar physiochemical properties with the bile acids. Using this condition, detected in the multiple reaction monitoring mode, the 15 bile acids, including three groups of isomers, were well quantified individually. Method validation showed that the linear regression relationship (r(2), 0.9993 - 0.9999), precisions (intra-day RSD, 0.96 - 4.31%; inter-day, 1.73 - 4.43%), and recovery (95.3 - 120.9%) were all satisfactory. The analysis results showed that bear bile and bezoar (Niu Huang) as well as their formulations contained large amounts of most of the 15 bile acids. In addition, this research revealed for the first time the presences of bile acids in animal waste medication used in traditional medicine from two clinics, Hei-Bing-Pian (discharges of wild boar) and Trogopterus Dung. The established method could be used for the quantification of other bile- or animal waste-based crude drugs and their formulated products.

Chemometrics: A new scenario in herbal drug standardization

Chromatography and spectroscopy techniques are the most commonly used methods in standardization of herbal medicines but the herbal system is not easy to analyze because of their complexity of chemical composition. Many cutting-edge analytical technologies have been introduced to evaluate the quality of medicinal plants and significant amount of measurement data has been produced. Chemometric techniques provide a good opportunity for mining more useful chemical information from the original data. Then, the application of chemometrics in the field of medicinal plants is spontaneous and necessary. Comprehensive methods and hyphenated techniques associated with chemometrics used for extracting useful information and supplying various methods of data processing are now more and more widely used in medicinal plants, among which chemometrics resolution methods and principal component analysis (PCA) are most commonly used techniques. This review focuses on the recent various important analytical techniques, important chemometrics tools and interpretation of results by PCA, and applications of chemometrics in quality evaluation of medicinal plants in the authenticity, efficacy and consistency.

Multi-component analysis of bile acids in natural Calculus bovis and its substitutes by ultrasound-assisted solid-liquid extraction and UPLC-ELSD

An ultrasound-assisted solid-liquid extraction (USLE) coupled to ultra-performance liquid chromatography-evaporative light scattering detection (UPLC-ELSD) method has been developed for the simultaneous extraction and determination of six bile acids (BAs) in natural Calculus bovis and its substitutes, collected from different origins. The USLE conditions, UPLC chromatographic and ELSD conditions for BAs were optimized. Under optimum conditions, the six target analytes were efficiently extracted and baseline separated within 10 min. The limits of detection (LODs) and quantification (LOQs) for six BAs were less than 7 ng and 22 ng, respectively. Average recoveries were within the range of 98.8-100.7% with relative standard deviations (RSDs) <2% for the six analytes. This method, due to its convenience, high selectivity, fast analysis efficiency and good reproducibility can be employed for analyzing the content differences of six BAs in 40 batches of natural C. bovis and its existing substitutes. The differences of the content of each BA in natural C. bovis and its substitutes were significant, and the total contents of six BAs in 13 batches of natural C. bovis were in the range of 7.96-160.17 mg g(-1), in 20 natural C. bovis of 0-245.89 mg g(-1), in 2 artificial cultivated C. bovis of 178.48-194.22 mg g(-1), in 3 cultured C. bovis of 41.01-107.3 mg g(-1), and in 2 counterfeit C. bovis of 144.9-340.25 mg g(-1). The significant differences of multi-component contents reflected the various inherent qualities of these samples, so, the use of these substitutes as the replacers of natural source in clinic should be paid more attention. Some substitutes could not be used as the replacers.

Quantitative analysis of five kudinosides in the large-leaved Kudingcha and related species from the genus Ilex by UPLC-ELSD

INTRODUCTION

The large-leaved Kudingcha from the genus Ilex, which is used as a traditional Chinese tea, contains several characteristic triterpenoid saponins that can be subjected to quality control evaluation.

OBJECTIVE

To develop and validate a rapid method incorporating reverse-phase ultra-performance liquid chromatography coupled with evaporative light scattering detection (UPLC-ELSD) for the simultaneous determination of the five triterpenoid saponins kudinoside L (1), kudinoside C (2), kudinoside A(3), kudinoside F(4) and kudinoside D(5) in several species of the large-leaved Kudingcha from the genus Ilex and 'Yerba Mate' (Ilex paraguariensis).

METHODOLOGY

The five compounds were separated using a water-acetonitrile mobile phase with a Waters Acquity BEH C(18)-column (100 × 2.1 mm, 1.7 µm).

RESULTS

Separation took 13 min with detection and quantification limits ranging from 12.5 to 29.8 ng and 41.3 to 98.2 ng, respectively. The method was validated according to the regulatory guidelines with respect to precision, stability, repeatability and recovery. The triterpenoid saponins showed a good regression relationship (r(2) > 0.999) within the test ranges, and the recovery of the method was in the 95-105% range.

CONCLUSION

The present method can be used successfully for the quality control of the large-leaved Kudingcha. The different Ilex species showed differences in distribution of the five triterpenoids. Ilex kudingcha, which makes up the major species of the large-leaved Kudingcha, contains the maximum amount of triterpenoid saponins.

HPLC-ELSD analysis of 18 platycosides from balloon flower roots (Platycodi Radix) sourced from various regions in Korea and geographical clustering of the cultivation areas

An effective HPLC method to analyse platycosides from the balloon flower root was developed using ELSD. The optimum resolution of the platycosides was achieved on an ODS column with gradient elution of eluent A, 30mM ammonium acetate buffer (pH 4.81): methanol: acetonitrile=75:5:20 (v/v/v), and B, 69:5:26 (v/v/v). Amongst 18 platycosides, platycoside E showed the highest content, followed by polygalacin D₂ and 3″-O-acetylplatyconic acid A. The sum of these three compounds was recommended for quality control of balloon flower root for medicinal purposes. The samples could be clustered into groups based on platycoside content. Group I, characterised by a high concentration of platycosides, was located near the west coast of Korea, whereas group II, characterised by a low concentration of platycosides, was located inland or in mountainous area. The method could be used to control the quality of balloon flower root.

Improved method for analyzing the degradation of estrogens in water by solid-phase extraction coupled with ultra performance liquid chromatography-ultraviolet detection

We established an improved method for the determination of four estrogens including estriol (E3), 17beta-estradiol (E2), 17alpha-ethynylestrodiol (EE2) and estrone (El) in water. The method consisted of solid-phase extraction (0.5 L water) and subsequent analysis of analytes by ultra-performance liquid chromatography (UPLC) with an ultraviolet detector (UVD). Base-line separation was achieved for all studied estrogens using a column (50 mm x 2.1 mm) packed with 1.7 microm particle size stationary phase. Recovery was higher than 88% and detection limits ranged between 12.5-23.7 ng/L for the four estrogens, with the RSD ranging from 7% to 11%. The method was successfully applied to determine E2 and EE2 in simulated natural water, which found that about 70% of E2 was degraded (with a half-life of about 30 hr) within 48 hr and about 55% of EE2 was degraded (with a half-life of about 36 hr). Low levels of E1 were found, however E3 was undetectable during the process.