20 potentially new compounds and 11 new bioactive constituents found in Smilacis Glabrae Rhizoma utilizing HPLC-DAD-ESI-IT-TOF-MSn.

INTRODUCTION: Smilacis Glabrae Rhizoma (SGR) is rich in chemical constituents with a variety of pharmacological activities. However, in-depth research has yet to be conducted on the chemical and pharmacodynamic constituents of SGR. MATERIALS AND METHODS: In this study, the chemical constituents of SGR were analyzed using liquid chromatography-mass spectrometry, and the pharmacodynamic compounds responsible for the medicinal effects of SGR were elucidated through a literature review. RESULTS: In total, 20 potentially new compounds, including 16 flavonoids (C19, C20, and C27-C40) and four phenylpropanoids (C107, C112, C113, and C118), together with 161 known ones were identified in the ethanol extract of SGR using liquid chromatography-mass spectrometry, and 25 of them were unequivocally identified by comparison with reference compounds. Moreover, 17 known constituents of them were identified in the plants of genus Smilax for the first time, and 16 were identified in the plant Smilax glabra Roxb. for the first time. Of 161 known compounds, 84 constituents (including isomers) have been reported to have 17 types of pharmacological activities, covering all known pharmacological activities of SGR; among these 84 bioactive constituents, six were found in the plants of genus Smilax for the first time and five were found in S. glabra for the first time, which are new bioactive constituents found in the plants of genus Smilax and the plant S. glabra, respectively. CONCLUSION: The results provide further information on the chemical composition of SGR, laying the foundation for the elucidation of the pharmacodynamic substances of SGR.

[Identification of chemical constituents in ethyl acetate soluble extract of Sinopodophylli Fructus based on HPLC-MS~n].

A high performance liquid chromatography with a diode array detector combined with electrospray ionization ion trap time-of-flight multistage mass spectrometry(HPLC-DAD-ESI-IT-TOF-MS~n, HPLC-MS~n) method was established for qualitative analysis of the chemical components of ethyl acetate extract from Sinopodophylli Fructus. The analysis was performed on a Kromasil 100-5 C_(18)(4.6 mm×250 mm, 5 µm) column, with a mobile phase consisted of 0.1% formic acid(A) and acetonitrile(B) for gradient at a flow rate of 1.0 mL·min~(-1). Electrospray ionization ion trap time-of-flight multistage mass spectrometry was applied for qualitative analysis under positive and negative ion modes. With use of reference substance, characteristic fragmentation and their HR-MS data, 102 components were identified, including 67 flavonoids and 35 lignans. Among them, 45 compounds were reported in Sinopodophylli Fructus for the first time and 19 compounds were identified as new compounds. PharmMapper was used to predict the bioactivity of compounds that were first reported in Sinopodophylli Fructus, and 20 compounds of them were identified to have potential anticancer activity. The results showed that there were many isomers in the ethyl acetate extract of Folium Nelumbinis, and a total of 19 groups of isomers were found. Among them, C_(21)H_(20)O_8 had the highest number of isomers(18 compounds), all of which were α-peltatin or its isomers; C_(21)H_(20)O_7 ranked second, with 10 compounds, all of which were 8-prenylquercetin-3-methyl ether or its isomers. In conclusion, an HPLC-MS~n method was established for qualitative analysis of the ethyl acetate extract(with anti-breast cancer activity) from Sinopodophylli Fructus in this study, which will provide the evidence for clarifying pharmacological active ingredients of the ethyl acetate extract from Sinopodophylli Fructus against breast cancer.

[Identification based on HPLC and anti-inflammatory targets as well as related constituents analysis of Asarum heterotropoides var. mandshuricum and A. sieboldii].

The present work is to establish an HPLC characteristic chromatograms of Asarum heterotropoides var. mandshuricum(AH) and A. sieboldii(AS), combined with cluster analysis for the identification of the two species, and predict their potential anti-inflammatory related targets by network pharmacological method. Eighty-nine samples(12 batches of AS and 77 batches of AH) were analyzed, and 11 characteristic peaks were identified by reference substances, UV spectrum and LC-MS. Cluster analysis showed that AS and AH were divided into two groups, and the ratio of characteristic peak areas can be used to distinguish them. When the ratio of characteristic peak sarisan to kakuol was greater than 5, it was AS, and when the ratio was less than 2, it was AH. The network pharmacological analysis of 119 constituents of Asari Radix et Rhizoma suggested that the anti-inflammatory effect of Asari Radix et Rhizoma might be related to COX-2, COX-1, iNOS, MAPK14, NR3 C1, PPARG and TNF. Among them, COX-2 is a relatively key target, which interacted with the characteristic constituents, asarinin, sesamin, safrole, methyleugenol and sarisan. The characteristic constituents asarinin and sesamin also interacted with the iNOS and MAPK14. Safrole and sarisan can also interact with iNOS, COX-1 and LAT4 H. Methyleugenol also showed interaction with COX-1 and LAT4 H. Since asarinin and sesamin interacted with three targets, COX-2, iNOS and MAPK14, it implied that they were the main active constituents for the anti-inflammatory activity of Asari Radix et Rhizoma. The COX-2 inhibitory activities of asarinin and sesamin were further studied by molecular docking and bioassay. The HPLC method established was simple, feasible and reliable, with predicted anti-inflammatory targets and anti-inflammatory constituents, which could provide a reference for improving the quality evaluation system of Asari Radix et Rhizoma.

Metabolites of Medicarpin and Their Distributions in Rats.

Medicarpin is a bioactive pterocarpan that has been attracting increasing attention in recent years. However, its metabolic fate in vivo is still unknown. To clarify its metabolism and the distribution of its metabolites in rats after oral administration, the HPLC-ESI-IT-TOF-MSn technique was used. A total of 165 new metabolites (13 phase I and 152 phase II metabolites) were tentatively identified, and 104, 29, 38, 41, 74, 28, 24, 15, 42, 8, 10, 3, and 17 metabolites were identified in urine, feces, plasma, the colon, intestine, stomach, liver, spleen, kidney, lung, heart, brain, and thymus, respectively. Metabolic reactions included demethylation, hydrogenation, hydroxylation, glucuronidation, sulfation, methylation, glycosylation, and vitamin C conjugation. M1 (medicarpin glucuronide), M5 (vestitol-1'-O-glucuronide) were distributed to 10 organs, and M1 was the most abundant metabolite in seven organs. Moreover, we found that isomerization of medicarpin must occur in vivo. At least 93 metabolites were regarded as potential new compounds by retrieving information from the Scifinder database. This is the first detailed report on the metabolism of ptercarpans in animals, which will help to deepen the understanding of the metabolism characteristics of medicarpin in vivo and provide a solid basis for further studies on the metabolism of other pterocarpans in animals.

Chemical Constituents from the Roots and Rhizomes of Asarum heterotropoides var. mandshuricum and the In Vitro Anti-Inflammatory Activity.

Anti-inflammatory compounds were investigated from the ethanol extract of the roots and rhizomes of Asarum heterotropoides var. mandshuricum, a traditional Chinese medicine called Xixin and used for pain and inflammatory. Nine new compounds were isolated, including six new lignans, neoasarinin A-C (1-3), neoasarininoside A and B (4 and 5), and asarinin B (7), and one new monoterpene, asarincin A (8), two new amides, asaramid II and III (10 and 11), and one new natural monoterpene, asaricin B (9), along with 37 known compounds (6, 12-47). Their structures and absolute configurations were elucidated on the basis of spectroscopic methods and chemical analyses. This is the first report of the absolute configuration of asarinin A (6). The 8-O-4' neolignans (1-5) were reported in the genus Asarum for the first time. The 15 compounds 17, 19, 22-25, 28, 31, 36, 40, 42, 43, 45-47 were isolated from the genus Asarum, and compounds 16, 32, 33, 37 and 39 were isolated from A. heterotropoides var. mandshuricum for the first time. Thirty-seven of the isolates were evaluated for anti-inflammatory activity against the release of ß-glucuronidase in polymorphonuclear leukocytes (PMNs) induced by the platelet-activating factor (PAF), and compounds 1, 4, 7, 8, 14, 17-19, 22, 24, 25, 29, 30, 32, 33, 40-43, 45, and 46 showed potent anti-inflammatory activities in vitro, with 27.9%-72.6% inhibitions at 10-5 mol/L. The results of anti-inflammatory assay suggested that lignans obtained from the CHCl3 extract might be the main active components of Xixin.

[Research on inorganic elements of Asari Radix et Rhizoma from different localities and species].

OBJECTIVE: To explore the character of inorganic elements in Asari Radix et Rhizoma (Xixin). METHOD: The contents of 53 inorganic elements in Xixin samples from different localities and species were determined by ICP-AES and ICP-MS. The statistical data were made using SAS. RESULT: The result demonstrated that Xixin has the high contents of Fe, Cr, Li. It has been observed that the content of Cu and Pb of the samples are much higher than the standard level. The results of hierarchical cluster analysis revealed two groups which correspond with the species of the samples. No correlations between the contents of the inorganic elements and the localities of the samples were found. Some characteristic elements were displayed in some specific areas. The difference of the contents of the 53 inorganic elements between root and rhizome of Xixin was reported for the first time. The primary form of inorganic elements in Xixin has been studied for the first time. The result demonstrated that the extraction rate between different elements varied, with the average extraction rate of (22.25 +/- 24.96)%. CONCLUSION: The inorganic elements analysis of Xixin can provide evidence of its identification, cultivation and application.

[Simultaneous determination of five constituents in eight Qingyedan species derived from Swertia plants by HPLC].

OBJECTIVE: To develop an HPLC method for simultaneous determination of swertiamarin, gentiopicroside, sweroside, mangiferin, erythrocentaurin, and to detect these five constituents in eight Qingyedans derived from Swertia mileensis, S. cincta, S. patens, S. punicea, S. delavayi, S. nervosa, S. macrosperma and S. yunnanensis. METHOD: The separation was carried out on a Thermo BDS Hypersil C18 (4. 6 mm x 250 mm, 5 microm) column eluted with mobile phase of water containing 0. 1% phosphoric acid and methanol (B) in gradient program (0-10 min, 18%-20% B; 10-30 min, 20%-35% B; 30-35 min, 35%-60% B). The column temperature was 32 degrees C , and the detection wavelength was set at 250, 260, 225 nm. The flow rate was 0. 7 mL . min-1 from 0 to 30 min, and be increased to 1. 0 mL . min-1 in 35 min. RESULT: The five compounds were well separated. The linear response ranges of swertiamarin, gentiopicroside, sweroside, mangiferin, erythrocentaurin were 0. 072-13. 39, 0. 1204. 518, 0. 060-5. 050, 0. 025-1. 518, and 0. 031-0. 210 microg, respectively. The mean recoveries of five compounds were 97.03% -102. 7% (RSD 1. 8% -6.2% ). There are swertiamarin, gentiopicroside and sweroside in most samples, and mangiferin in half samples. But erythrocentaurin was only detected in a few samples. The contents of five compounds were different in different samples. The contents of swertiamarin in S. mileensis, S. patens, S. yunnanensis and S. delavayi are up to 34. 47-118.05 mg . g-1, the contents of gentiopicroside are up to 25. 91 mg . g-1 in S. cincta. In S. puncea all contents of swertiamarin, gentiopicroside, sweroside and mangiferin are higher, especially the content of sweroside. There are Xiao-Qingyedans and Da-Qingyedans called in markets, and they can be identified by the contents of swertiamarin, gentiopicroside and sweroside. S. punicea can be identified by the content of sweroside, and the ratio gentiopicroside/total content can be used for identification of S. cincta from other seven Qingyedan species. CONCLUSION: The method was certified to be accurate and reliable and can be used for identification and quality evaluation of traditional Chinese medicine Qingyedan derived from Swertia species.

Elucidation of the Mechanisms and Effective Substances of Paeoniae Radix Rubra Against Toxic Heat and Blood Stasis Syndrome With a Stage-Oriented Strategy.

In the clinical practice of traditional Chinese medicine, toxic heat and blood stasis syndrome (THBSS) is a common syndrome observed in various critical diseases. Paeoniae Radix Rubra (PRR) has known therapeutic effects on THBSS. However, its pharmacodynamic mechanisms and effective substances in the treatment of THBSS still need further elucidation. Our previous study indicated that THBSS had three stages of progression, and the abnormal biochemical indices of each stage were different. Therefore, this study aimed to elucidate the pharmacodynamic mechanisms and effective substances of PRR for the treatment of THBSS with a stage-oriented strategy. Specifically, research was performed separately in two stable stages of THBSS: the excessive heat and little blood stasis (EHLBS) and blood stasis (BS) stages. THBSS model rats, at different time periods after syndrome initiation (first 5 h for EHLBS and 24 h later for BS), were used to conduct the two-stage investigation. Targeted metabonomics analysis was performed to elucidate the pharmacodynamic mechanisms of PRR in the treatment of EHLBS or BS. Based on the relationship between the individual differences in blood drug concentrations and pharmacodynamic effects, partial least squares regression analysis was employed to screen for the effective substances from the original constituents and metabolites of PRR. We found that PRR could upregulate primary bile acid biosynthesis, glycerophospholipid metabolism, ether lipid metabolism, and five amino acid metabolic pathways (e.g., arginine and proline metabolism) to treat EHLBS. Meanwhile, PRR alleviated BS by upregulating primary bile acid biosynthesis and downregulating glycerophospholipid metabolism. But PRR had no obvious effects on ether lipid metabolism and amino acid metabolism in this stage. In total, 17 and 9 potential effective substances were found in the EHLBS and BS stages, respectively, among which there were only five common compounds between the two stages. To our knowledge, sixteen compounds were regarded as potential effective substances of PRR for the first time. Therefore, the pharmacodynamic mechanisms and effective substances of PRR in the treatment of EHLBS and BS were partly different. Overall, this stage-oriented strategy provides a new way to study the pharmacodynamic mechanisms and effective substances of traditional Chinese drugs.

Global Profiling and Structural Characterization of Metabolites of Ononin Using HPLC-ESI-IT-TOF-MSn After Oral Administration to Rats.

Ononin is a bioactive isoflavone of legumes. To explore the "effective forms" of ononin, its metabolites were characterized using HPLC-ESI-IT-TOF-MSn after oral administration to rats. Metabolites (106), including 94 new metabolites, were characterized, which contained 17 phase I, 23 hydroxylated and methylated, 54 sulfated, 10 glucuronidated, and 2 sulfated and glucuronidated metabolites. Six hydroxylated metabolites of formononetin (aglycone of ononin) were simultaneously detected for the first time. Twenty-three hydroxylated and methylated metabolites were the new metabolites of ononin, and the number of hydroxylation and methylation was 1-3 and 1-2. Twenty metabolites have ononin-related bioactivities, and many metabolites have the same bioactivities. Their probable mechanisms of action may be additive and/or synergistic effects, especially because of the addition of the blood concentrations of these compounds. The results provide a foundation for a better understanding of the "effective forms" of ononin.

Discovery of the active compounds of Smilacis Glabrae Rhizoma by utilizing the relationship between the individual differences in blood drug concentration and the pharmacological effect in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: This study addresses the rapid discovery of the active compounds (the original constituents and/or metabolites) of a traditional Chinese drug, Smilacis Glabrae Rhizoma (SGR). AIM OF THE STUDY: The aim of this study was to develop a new method to find out the active compounds of traditional drugs in vivo. MATERIALS AND METHODS: A method was established to discover and identify the potential active compounds in drug-containing plasma from rats that were orally administered SGR extract, utilizing the relationship between the individual differences in blood drug concentrations in the rats and the resulting differences in pharmacological effect, and the method was denoted as the RID-PE method. For this method, we used high-performance liquid chromatography with a diode array detector combined with electrospray ionization ion trap time-of-flight multistage mass spectrometry (LC-MSn) to identify the compounds (the original constituents and metabolites) and to determine the peak areas of the compounds in drug-containing plasma following SGR treatment. The anti-inflammatory effect of SGR was evaluated using a carrageenan-induced inflammatory rat model. According to the percent inhibition of paw edema in each model rat (14 rats total) orally administered SGR extract, the plasma samples from the rats were sorted and divided into 7 groups. Each group consisted of two plasma samples, and their percent inhibition of paw edema were similar to each other. We performed an LC-MSn analysis on 3 plasma groups, which showed large differences in the inhibition rates, with percent inhibitions of 92.7%, 72.4% and 38.4%. The correlation coefficients (r) between the peak area of each compound and the pharmacological effect (inhibition ratio) of SGR in the three groups were analyzed using SPSS software. When the correlation coefficients of the compounds are greater than 0.8 (0.8 < r ≤1), these compounds are strongly and positively correlated with anti-inflammatory activity, making them potential anti-inflammatory active compounds. RESULTS: Fifty-eight potential anti-inflammatory compounds (0.8 < r ≤ 1) from SGR were discovered in model rat plasma using the RID-PE method, 47 of which were considered to be new potentially anti-inflammatory compounds. Among these compounds, four original constituents and 5 isomers of potential anti-inflammatory metabolites were validated to have significant anti-inflammatory effects, and they included astilbin, syringic acid, catechin, coumalic acid, resveratrol-3'-O-glucuronide (RG, isomer of M2 or M3), 3'-O-methyl-(+)-epicatechin-4'-O-glucuronide (CA-1, isomer of M16), 4'-O-methyl-(+)-epicatechin-3'-O-glucuronide (CA-2, isomer of M16), 4'-O-methyl-(+)-epicatechin-7-O-glucuronide (CA-3, isomer of M16) and 3'-O-methyl-(+)-epicatechin-7-O-glucuronide (CA-4, isomer of M16). In addition, four isomers (CA-1-CA-4) were reported to have anti-inflammatory effects for the first time, and CA-3 was a new compound. CONCLUSIONS: The RID-PE method can be used to discover and identify the active constituents and metabolites of SGR systematically and in vivo. Furthermore, these findings enhance our understanding of the metabolism and effective forms of SGR.

Profiling the metabolites of astrapterocarpan in rat hepatic 9000g supernatant.

Astrapterocarpan (AP) is a bioactive constituent of Astragali Radix and was selected as a model compound for investigating the in vitro metabolism of pterocarpans in this study. Its in vitro metabolism was conducted by incubation with rat hepatic 9000g supernatant (S9) in the presence of an NADPH-generating system. At first, four compounds were isolated and their structures were elucidated as 6a-hydroxy-AP (M1), astrametabolin I [M2, 1a-hydroxy-9, 10-dimethoxy-pterocarp-1(2), 4-diene-3-one], 9-demethyl-AP (M3, nissolin) and 4-methoxy-astraisoflavan (M4, 7, 2'dihydroxy-4, 3', 4'-trimethoxy-isoflavan) on the basis of NMR data, respectively. Among them, M1, M2 and M4 were new compounds. Next, the metabolite profile of AP in rat hepatic S9 was obtained via HPLC-DAD-ESI-IT-TOF-MSn, and 40 new metabolites were tentatively identified. These newly identified metabolites included 9 monohydroxylated metabolites, 1 demethylated metabolite, 7 demethylated and monohydroxylated metabolites, 4 dihydroxylated metabolites, 1 hydration metabolite, 1 didemethylated metabolite, 2 glucosylated metabolites, 1 monohydroxylated and dehydrogenated metabolite, 2 monohydroxylated and demethylated and dehydrogenated metabolites, 2 dimerized metabolites, 3 dimerized and monohydroxylated metabolites, 2 dimerized and didemethylated metabolites, and 5 dimerized and demethylated metabolites. Finally, the major metabolic reactions of AP in rat hepatic S9 were summarized and found to be hydroxylation, demethylation, dimerization, hydration, and dehydrogenation. More importantly, the biotransformation from AP to M2 and the dimerization of AP by incubation with hepatic S9 were reported for the first time. In conclusion, this is the first report on the metabolism of a pure pterocarpan in animal tissues, and these findings will provide a solid basis for further studies on the metabolism of other pterocarpans.

Comparison of chemical constituents among licorice, roasted licorice, and roasted licorice with honey.

Licorice (root and rhizome of Glycyrrhiza uralensis Fisch.) is sometimes used as crude drug after processing. In this report, we prepared roasted licorice with or without honey using 3 lots of crude drug samples derived from wild G. uralensis, and analyzed the constituents in unprocessed, roasted, and honey-roasted licorice samples by high performance liquid chromatography-electrospray ionization-ion trap-time of flight mass spectrometry (HPLC-ESI-IT-TOF-MSn) with principal component analysis. We found that the areas of 41 peaks were noticeably changed by processing. Among them, the areas of 12 peaks, viz. isoliquiritin, isoliquiritigenin, glucoisoliquiritin, 6″-O-acetylisoliquiritin, 6″-O-acetylisoliquiritin apioside, glycyrrhetinic acid 3-O-glucuronide, 5 kinds of sugar-derivatives and one compound whose molecular weight was 386 Da were increased by roasting in all 3 lots, and those peak areas were increased by higher heating temperatures. Among the increased peaks, 3 kinds of sugar-derivatives had larger areas, and 6″-O-acetylisoliquiritin had lower areas than those in honey-roasted licorice. Those sugar-derivatives were the only characteristics differing between honey-roasted licorice and roasted licorice. Meanwhile, the areas of 9 peaks, four of them identified as 6″-O-acetylliquiritin, 6″-O-acetylliquiritin apioside, formononetin and gancaonin L, were decreased by roasting in all 3 lots, but there were no differences between roasted licorice with or without honey. Those compounds whose amounts were changed by processing could be used as markers for the quality control of roasted and honey-roasted licorice.

Phenanthrene derivatives from roots and rhizomes of Asarum heterotropoides var. mandshuricum.

Five new phenanthrene derivatives: 9-ethoxy-7-methoxy-aristololactam IV (1), norcepharadione A N-ß-d-glucopyranoside (2), aristololactamoside I (3), aristololactamoside II (4) and aristothiolactoside (5) together with eleven known phenanthrene derivatives (6-16) were isolated from the ethanol extract of the roots and rhizomes of Asarum heterotropoides var. mandshuricum. The aristololactams with substitution of ethoxy at C-9 position (1, 9, and 10) and the sulfur-containing phenanthrene derivative (5) were reported in the genus Asarum for the first time. Furthermore, six phenanthrene glucoside derivatives (2-5, 13 and 14) were also found in this genus for the first time and compounds 7 and 9-15 were isolated from the genus Asarum for the first time. Six of them (1, 2, 9, 10, 13 and 14) were submitted to cytotoxicity test against human renal proximal tubular epithelial cell lines (HK-2) using MTT and LDH assays. Compounds 1 and 10 showed significant cytotoxic activity against HK-2 cell lines with IC50 values of 18.18 and 20.44µmol/L in MTT assay and 84.36 and 35.06µmol/L in LDH assay, respectively. Compound 9 showed moderate cytotoxicity in MTT assay with IC50 values of 95.60µmol/L, but no cytotoxicity in LDH assay. Compounds 2, 13 and 14 showed cytotoxic effect in neither MTT assay nor LDH assay. Considering the other nephrotoxic phenanthrene derivatives (6, 8, 12, 15 and 16) previously tested, the results implied the potency of renal toxicity of this herb used as a medicine.

Application of microscopy for discrimination of eight Swertia species utilized in the traditional Chinese medicine "Qingyedan".

Many Swertia species are utilized as a traditional medicine under the name "Qingyedan" in China, but are easily confused with one another. To distinguish eight Swertia species (S. mileensis, S. cincta, S. patens, S. punicea, S. delavayi, S. nervosa, S. macrosperma, and S. yunnanensis) and to ensure their safety and efficacy, the microscopic and macroscopic characteristics of the roots, stems, leaves, and flowers of them were examined. The results showed that microscopic and macroscopic features helpful for authentication of the eight species were the sinuosity of the anticlinal walls of epidermal cells and presence or absence of hairs on the leaf lamina; presence or absence of V-shaped fibers and fibers with sinuous abaxial wall in the sepals; shape of epidermal cells and pattern of papillae on hairs on the margin of corolla nectary; distribution of stomata in leaf and sepal epidermises, stone cells in cortex and phloem of roots and in cortex and pith of stems, crystals in parenchymatous cells of mesophyll and stem, stomata size, stem diameter, and 4- or 5-merous flowers, and so on. Two keys to the eight Swertia species based on macroscopic and microscopic characteristics are presented. The study indicates that microscopy and related techniques are convenient, practicable, and can be unambiguously applied for authentication of Swertia species.

Studies on morphology and aristolochic acid analogue constituents of Asarum campaniflorum and a comparison with two official species of Asari radix et rhizoma.

Dried whole herbs or roots and rhizomes of Asarum campaniflorum have been sold under the trade name Xixin and used as folk remedies in its producing areas for a long time. In order to avoid the misuse of A. campaniflorum as official species of Xixin (Asari radix et rhizoma), a comparative study based on the morphological and phytochemical analysis of the aerial and underground parts was carried out. The usual morphological methods and a microscopic imaging system were used. The results show that A. campaniflorum could be easily distinguished from two official species (Asarum sieboldii and A. heterotropoides var. mandshuricum) by the diameter of thicker roots (1.3-2.7 mm), distinct large parenchymatous cells in phloem of roots, and the size of oil cells in upper leaf epidermises [(40)80-140(174) microm in diameter, where numbers in parentheses are for rare cases], etc. Nine aristolochic acid analogues (AAAs) were identified and estimated by high-performance liquid chromatography-diode array detection (HPLC-DAD). The aerial and underground parts of A. campaniflorum contained 3-4 AAAs, i.e., aristololactam-II-N-beta-D-glucoside (AL-II-Glc), aristololactam I (AL-I), aristololactam II (AL-II), and aristolochic acid I (AA-I), while only AL-I was detected in underground parts of A. sieboldii and no AAAs were detected in underground parts of A. heterotropoides var. mandshuricum. The respective contents (in mg/g) in aerial and underground parts of A. campaniflorum, were as follows: AL-I, 0.06-0.12, 0.05-0.10; AL-II, 0.03-0.04, 0.01-0.03; AA-I, 0.01-0.02, 0.0-0.0. These data suggest A. campaniflorum has a high risk of causing aristolochic acid nephropathy. All these discoveries can contribute to not only the better understanding of this new resource species, but also the safe use of the crude drug Xixin.