Identification and Analysis of NnOMT and NnNMT Gene Families in Nelumbo nucifera / 中国实验方剂学杂志

ObjectiveThe biosynthetic pathways of benzylisoquinoline alkaloids（BIAs） in Nelumbo nucifera are of great theoretical and economic value. In this paper， N. nucifera O-methyltransferase（NnOMT） and N. nucifera N-methyltransferase（NnNMT） gene families were identified and analyzed by bioinformatics in order to facilitate the biosynthetic pathway of BIAs in N. nucifera. MethodBased on the whole genome of N. nucifera， UniPort and National Center for Biotechnology Information（NCBI） databases were used to identify the NnOMT and NnNMT gene families of N. nucifera， and analyze their physicochemical properties and subcellular localization， then TBtools， MEME， MEGA 11.0， FigTree 1.4.4 and other tools were used to analyze the phylogeny， sequence characteristics， gene structure， functional annotation and cis-acting elements of NnOMT and NnNMT genes identified in the previous stage. ResultA total of 61 NnOMT and NnNMT genes were identified in this paper， the number of amino acids encoded by these genes ranged from 168 aa to 580 aa， the isoelectric point ranged from 4.76 to 9.16， and the relative molecular weight ranged from 18 699.52 Da to 64 934.53 Da， most of which showed acidic and mostly hydrophilic proteins. There were 10 conserved motifs， Kyoto Encyclopedia of Genes and Genomes（KEGG） analysis enriched a total of 12 pathways， including metabolism， biosynthesis of phenylpropane and isoquinoline alkaloids， etc. And Visualization of Gene Ontology（GO） enrichment results showed that 61 NnOMT and NnNMT genes were annotated to 32 items， which included 16 molecular functions［such as reduced nicotinamide adenine dinucleotide（NADH） activity and exopeptidase activity］ and 16 biological processes（such as metabolic process of carbon tetrachloride， anaerobic carbon tetrachloride metabolic process and responses to exogenous biological stimuli）. There were a variety of cis-acting elements in the promoter regions of NnOMT and NnNMT genes， mainly promoter and enhancer regions element， light responsive element and methyl jasmonate responsive element. ConclusionIn this study， a comprehensive bioinformatics analysis of 61 NnOMT and NnNMT genes is carried out based on the genome data of N. nucifera， which lays a foundation for research on the gene structure and function of NnOMT and NnNMT gene families， and provides a reference for biosynthetic pathway elucidation of BIAs in N. nucifera.

Two new isoquinoline alkaloids from Corydalis hendersonii / 中国中药杂志

Corydalis hendersonii(CH) is a Tibetan folk medicine with the functions of clearing heat, detoxifying, cooling blood, checking diarrhea, and lowering blood pressure. It is often used to treat high altitude polycythemia, vasculitis, peptic ulcer, and diarrhea. Nine compounds were separated from the ethanol extract of CH by silica gel, ODS, Sephadex LH-20 chromatography and semi-preparative HPLC. Their structures were identified as hendersine H(1),hendersine I(2), dehydrocheilanthifoline(3), protopine(4), izmirine(5), 6,7-methylenedioxy-1(2H)-isoquinolinone(6), icariside D_2(7), ethyl 4-(β-D-glucopyranosyloxy)-3-methoxybenzoate(8), 3-hydroxy-4-methoxybenzoic acid(9), respectively, by the spectroscopic data analysis and comparison with those in the literature. Among them, compounds 1 and 2 are new isoquinoline alkaloids, and compounds 7-9 are reported the first time for Corydalis. The hypoglycemic model of H9c2 cardiomyocytes and the inflammatory model of H9c2 cardiomyocytes induced by conditional supernatant were employed to determine the activities of the above compounds. The results showed that 20 μmol·L~(-1) compound 1 had a protective effect on H9c2 cardiomyocytes and 10 μmol·L~(-1) compounds 4 and 5 inhibited H9c2 cardiomyocyte inflammation induced by conditional supernatant.

Characterization and identification of alkaloids in Phellodendri Chinensis Cortex and Phellodendri Amurensis Cortex based on UHPLC-IM-Q-TOF-MS / 中国中药杂志

A strategy combining collision cross section(CCS) prediction and quantitative structure-retention relationship(QSRR) model for quinoline and isoquinoline alkaloids was established based on UHPLC-IM-Q-TOF-MS and applied to Phellodendri Chinensis Cortex and Phellodendri Amurensis Cortex. The strategy included the following three steps.(1) The molecular features were extracted by the "find features" algorithm.(2) The potential quinoline and isoquinoline alkaloids were screened by filtering the original characteristic ions extracted from Phellodendri Chinensis Cortex and Phellodendri Amurensis Cortex by the established CCS vs m/z prediction interval.(3) According to the retention time of candidate compounds predicted by QSRR model, the chemical constituents were identified in combination with the characteristic fragment ions and pyrolysis law of secondary mass spectrometry. With the strategy, a total of 80 compounds were predicted, and 15 were identified accurately. The strategy is effective for the identification of small analogs of traditional Chinese medicine.

Molecular identification and alkaloids content of endangered Chinese medicinal plant Coptis chinensis var. brevisepala / 中国中药杂志

According to the records of Chinese materia medica,Coptis chinensis var. brevisepala is an authentic Chinese medicinal plant highly recommended by ancient physicians since its rhizome is like a string of beads and has a good medicinal value. However,its medicinal components and values remain to be studied as it is endangered because of overexploitation. Therefore,this study aims to quantitatively determine its effective components based on UPLC-QTOF-MS,and to compare the contents of isoquinoline alkaloids in C.chinensis var. brevisepala with those in other Coptis species. Meanwhile,molecular methods accurately identified 12 batches of C. chinensis var. brevisepala,9 batches of C. chinensis,4 batches of C. deltoidea,and 1 batch of C. teeta. Gradient elution was performed with Waters CORTECS C18 column( 4. 6 mm× 150 mm,2. 7 μm) and the mobile phase acetonitrile-water with 0. 4% formic acid. Mass spectrometry was conducted in ESI positive mode. The quantitative results showed that 8 main alkaloids had a good linear relationship within the concentration range( R~2>0. 996),with the recovery rate of 95. 18%-105. 0% and the RSD of 0. 28%-3. 7%. Compared with that of other Coptis species,the rhizome of C. chinensis var. brevisepala had the highest contents of berberine and columbamine. The total content of the 8 alkaloids in C. chinensis var. brevisepala was similar to that in C. chinensis but higher than that of the other two species. PCA was performed to compare the alkaloids among the 4 species. Besides,the 8 alkaloids were evaluated in different parts of C. chinensis var. brevisepala. The results indicate that this method is reliable and efficient and can provide a reference for the quality research.

Research progress on medicinal resources of Coptis and its isoquinoline alkaloids / 中国中药杂志

Coptidis Rhizoma is a common Chinese medicinal in clinical practice,with the effects of clearing heat,drying dampness,purging fire,and removing toxin. All the medicinal plants of Coptis can be used for clinical treatment,but some species are endangered due to resource destruction and difficulty in planting. The dominant medicinal components in Coptidis Rhizoma are isoquinoline alkaloids. There are various methods for the analysis and detection of alkaloids,such as LC-MS,HPLC,and TLC,among which LC-MS is the most widely applied. Different plants of Coptis vary in the kind and content of alkaloids. C. chinensis,C. deltoidea,C. teeta,C. chinensis var. brevisepala,C. omeiensis,C. quinquefolia,and C. quinquesecta mainly contain berberine,palmatine,coptisine,jatrorrhizine,and columbamine,five effective alkaloid components. Plant isoquinoline alkaloids( PIAs) have strong pharmacological activity but are difficult to prepare. The application of synthetic biology of PIAs will be helpful for the clinical application of PIAs. This paper reviews the research progress on biological resources of Coptis species and structures of alkaloids as well as analysis methods and synthetic biology for isoquinoline alkaloids in the medicinal plants of Coptis in recent years,which will facilitate the protection of Coptis medicinal resources and the application and development of alkaloids.

A new antiviral isoquinoline alkaloid from Thalictrum glandulosissimum / 中国中药杂志

A new isoquinoline alkaloid(1) has been isolated from the whole plant of Thalictrum glandulosissimum by using various chromatographic techniques, including silica gel, sephadex, MCI-gel resin, and RP-HPLC, and its structure was determined as 1-(6-hydroxy-7-methylisoquinolin-1-yl) ethantone by physicochemical properties and spectroscopic data. This compound was evaluated for anti-tobacco mosaic virus(TMV) activity. The results showed that it had prominent anti-TMV activity with inhibition rates of 28.4%. This rate was closed to that of positive control.

Isolation and Elucidation of a Novel Isoquinoline Alkaloid from Corydalis hendersonii / 中国实验方剂学杂志

As part of systematic research of Corydalis hendersonii,a typical traditional Tibetan herbal medicine with clearing heat,relieving pain,and lowering blood pressure effects,a novel isoquinoline alkaloid,named hendersine G was isolated from the ethanol extract of the whole plant by various chromatographic techniques,including silica gel column,reverse phase column (ODS),Sephadex LH-20,and semi-preparative HPLC.Its structure was elucidated by MS,NMR and other spectroscopic data analysis.Hendersine G can be regarded as a condensation product of a tetrahydroberberine and a succinic acid,however,its absolute configuration has not been determined due to its structural complexity and less obtained amount.This present study provides an inspiration for further exploration of novel molecules from C.hendersonii.

Rollinia mucosa (Jacq) Baillon (Annonaceae) active metabolites as alternative biocontrol agents against the lace bug Corythucha gossypii (Fabricius): an insect pest / Metabolitos activos de la semilla de Rollinia mucosa (Jacq) Baillon (Annonaceae) como agentes alternativos de biocontrol sobre el insecto fitopatógeno Corythucha gossypii (Fabricius) / Metabólitos ativos de Rollinia mucosa (Jacq) Baillon (Annonaceae) como agentes de biocontrole alternativos contra Corythucha gossypii (Fabricius): um inseto-praga

Abstract The lace bug, Corythucha gossypii (Fabricius) is a serious pest affecting over 24 wild and commercially important plant species of the families Annonaceae, Passiflorcae, Caricaceae, Euphorbiaceae, and Solanaceae. Thus far, commercial insecticides, such as 0.1% Dimethoate and 0.1% Imidacloprid have shown effectiveness against this insect, but no botanical pesticides are available to control this bug. In the present study, a Rollinia mucosa (Jacq.) Baillon ethanol extract was evaluated as a biological control agent against the lace bug. Through a toxicity assay involving Artemia salina, the median lethal concentration (LC50) of a raw ethanol extract of R. mucosa seeds was determined, as well as that of its Acetogenin (F1) and Alkaloid (F2) fractions; these LC50 were 0.184, 0.082, and 0.0493 μg/mL, respectively. In addition, with an insecticide assay on lace bug nymphs, a mortality percentage of 86.67% at 5 μg/mL after 72h was observed. These data demonstrate that the R. mucosa seed extract is highly active. Further chemical characterization studies revealed that the main active metabolites contributing to extract activity were acetogenins and alkaloids.

Resumen El hemíptero, Corythucha gossypii (Fabricius) es un insecto que causa daño sustancial en cultivos de más de 24 especies de plantas de las familias Annonaceae, Passifloraceae, Caricaceae, Euphorbiaceae y Solanaceae. En su mayoría estas plantas son de interés económico. Aunque insecticidas comerciales como el Dimetoato (0.1%) y el Imidacloprid (0.1%) permiten un manejo eficiente de este insecto-plaga, no se han reportado alternativas botánicas para estos insecticidas sintéticos. En el presente estudio se evaluó el extracto etanólico de la semilla de Rollinia mucosa (Jacq.) Baillon, como un biocontrolador de C. gossypii. A través de un test de toxicidad con Artemia salina se determinó que la concentración del extracto etanólico letal para el 50% de la población bajo estudio (LC50) fue de 0.184 μg/mL. De igual modo se identificó que las fracciones de acetogeninas (F1) y de alcaloides (F2) de este extracto tienen un LC50 de 0.082 y 0.0493 μg/mL, respectivamente. En el ensayo insecticida con ninfas de C. gossypii se observó una mortalidad del 86.67% después de 72 horas de exposición al extracto etanólico a una concentración de 5 μg/mL. Lo anterior demuestra que el extracto es altamente activo. La caracterización química del extracto evidenció que los principales metabolitos activos que contribuyen a su actividad insecticida son las acetogeninas y los alcaloides.

Resumo Corythucha gossypii (Fabricius) é uma praga séria que afeta mais de 24 plantas silvestre e de interesse comercial, pertencentes as famílias Annonaceae, Passifloraceae, Caricaceae, Euphorbiaceae e Solanaceae. Até o momento, inseticidas comerciais como Dimetoato (0.1%) e Imidacloprid (0.1%) apresentam um controle eficiente sobre este inseto, entretanto não há reportes de pesticidas de origem vegetal para o seu controle. No presente estudo, o extrato etanólico de Rollinia mucosa (Jacq.) Baillon foi avaliado como um controle biológico contra Corythucha gossypii. Por meio do ensaio de toxicidade com Artemia salina a concentração letal média (LC50) para o extrato etanólico das sementes, suas frações de acetogeninas (F1) e fração de alcaloides (F2) foi de 0.184, 0.082 y 0.0493 μg/mL, respetivamente. Adicionalmente, na avaliação do ensaio inseticida, se obteve uma porcentagem de mortalidade de 86.67% à concentração de 5 μg/mL após de 72 horas de exposição, demonstrando uma alta atividade do extrato de sementes de R. mucosa. Os estudos em relação à caracterização química evidenciaram que os principais metabólitos que aportam à atividade do extrato foram as acetogeninas e alcaloides.

Research progress on aporphine alkaloids / 中草药

Aporphine alkaloids belong to isoquinoline alkaloids and have a wide range of physiological activities. These natural products and their derivatives are the lead compound of the novel drug for the treatment of various diseases. Based on many literatures, the plant distribution, biosynthetic pathways, natural organic synthesis methods and pharmacological activities of those aporphine alkaloids have been summarized in this paper, which would supported the deeply development about the pharmaceutical research based on the aporphine alkaloids.

Research progress on chemical constituents of Coptidis Rhizoma and its pharmacological activities / 中草药

As a commonly used Chinese materia medica, Coptis Rhizoma mainly contains isoquinoline alkaloids, lignans, coumarins, flavonoids, terpenes, steroids, organic acids, volatile oil, polysaccharides and other chemical compositions. Its pharmacological activities are hypoglycemic effect, antibacterial, anti-oxidation, anti-inflammatory, antitumor, hypoglycemic, lipid-lowering, anti-arrhythmic activities and so on. The significantly hypoglycemic activity has led to its earlier use in the treatment of diabetes. In this paper, the chemical constituents, hypoglycemic effects, and other pharmacological activities of Coptis Rhizoma in recent years are reviewed in order to provide a reference for the further development and rational utilization of this plant resource.

In vitro antibacterial effects of Zanthoxylum tingoassuiba root bark extracts and two of its alkaloids against multiresistant Staphylococcus aureus

ABSTRACT The emergence of multiresistant strains of bacteria reinforces the need to search for new compounds able to combat resistant organisms. Medicinal plants are a great resource of bioactive substances, providing the possibility of obtaining molecules with potential antimicrobial activity. The aim of the present study is the evaluation of the antibacterial activity of extracts and alkaloids isolated from the root bark of Zanthoxylum tingoassuiba A. St.-Hil., Rutaceae, against four resistant clinical isolates and Staphylococcus aureus ATCC 25923. The dichloromethane and methanol extracts were fractionated by chromatography on silica gel, leading to the isolation of dihydrocheleryhtrine and N-methylcanadine, identified by Nuclear Magnetic Resonance spectroscopy. The antibacterial activity of the extracts and isolated compounds was evaluated by the disc diffusion method and the minimum inhibitory concentration was determined. The dichloromethane extract was the most active against all the tested strains and the two pure alkaloids were more active than the extracts. The anti-MRSA activity of the two benzophenanthridine alkaloids is demonstrated for the first time in this study. These compounds appear as potential leads for the development of new anti-MRSA compounds and could be responsible for the antibacterial activity, justifying the ethnobotanical use of Z. tingoassuiba and other species for the treatment of various infectious diseases.

Alkaloids and biological activity of beribá (Annona hypoglauca)

ABSTRACT Annona hypoglauca Mart., Annonaceae, popularly known as “beribá”, was collected in flooded areas of the Amazonian Rain Forest. The crude extract obtained from this species was found to be cytotoxic against human cancer cells. Chemical information on A. hypoglauca is scarce. So, the present work aimed the isolation and identification of its alkaloids and to test their cytotoxic activity. Alkaloids were obtained from stem by acid–base partitioning and the remaining alkaloid-free extract was partitioned with organic solvents. Gas chromatography–mass spectrometry GC/MS analysis of total alkaloids allowed the identification of four aporphine alkaloids: actinodaphnine, anonaine, isoboldine and nornuciferine. Total alkaloids were fractionated by column chromatography and were purified by preparative thin-layer-chromatography, which allowed the isolation of two aporphine alkaloids, actinodaphnine and isoboldine, characterized by NMR and CG–MS analyses. This is the first report for the occurrence of actinodaphnine in Annona species. All the samples were tested in cytotoxic and antibacterial assays. Total alkaloid extract and its fractions showed antimicrobial activity against Staphylococcus aureus and Enterococcus faecalis. In the cytotoxicity assay, the crude extract showed a lethal effect against breast and colon cancer cells. Isoboldine-containing FA5 and actinodaphnine-containing FA6 showed activity against breast cancer cell line, while the alkaloid-free fractions did not show significant activity against cancer cell lines.

Analysis of isoquinoline alkaloids from Mahonia leschenaultia and Mahonia napaulensis roots using UHPLC-Orbitrap-MSn and UHPLC-QqQLIT-MS/MS / 药物分析学报

Mahonia leschenaultia (ML) and Mahonia napaulensis (MN) are less known and unexplored medicinal plants of the family Berberidaceae. They are used by the Todas of Nilgiris in their religious and medical practices but chemically less identified. Hence, we decided to do extensive phytochemical analysis to explore the potential of these plant extracts. An ultrahigh performance electrospray tandem mass spectrometry (UHPLC–ESI–MS/MS) method was successfully developed for qualitative analysis of the bioactive components in Mahonia species using Orbitrap Velos Pro mass spectrometer. Sixteen compounds were identified by comparison of their retention times and mass spectra (MS) with authentic standards and reported literature. Multi-stage mass spectra (MS2–8) for the identification of protoberberine and aporphine alkaloids showed the sequential expulsion of all the substituents attached with their basic skeleton followed by CO loss. Eight of the identified compounds (berberine, jatrorrhizine, palmatine, magnoflorine, isocorydine, glaucine, tetrahydropalmatine and tetrahydroberberine) were simultaneously determined by another UHPLC–ESI–MS/MS method under the multiple reactions monitoring (MRM) mode quantitatively using triple quadrupole linear ion trap mass spectrometer. The analytical method was validated for 8 bioactive compounds with overall recovery in the range 98.5%–103.6%(RSD≤2.2%), precise (RSD≤2.07%) and linear (r≥0.9995) over the concentration range of 0.5–1000 ng/mL and successfully applied in ML and MN roots, which suggests the suitability of the proposed approach for the routine analysis of Mahonia species and their quality control.

Phytochemical and pharmacological progress on Tibetan medicine Hypecoi Erecti Herba and plants of Hypecoum L / 中草药

Hypecoi Erecti Herba is one of ethnic and folk medicines in China, mostly known in Tibetan medicine. It has the function of heat-clearing and detoxifying, and analgesia, indicated for the treatment of a variety of heat syndrome, such as "Chi Ba" pestilence, and warm toxin. Previous phytochemical studies revealed isoquinoline alkaloids are its main chemical components, and contemporary pharmacological research demonstrated that Hypecoi Erecti Herba has antibacterial, liver protection, analgesic, anti-inflammatory, and antiviral activities. The present paper describes the resource distribution, chemical constituents, and pharmacological activities of the plants in Hypecoum L. to provide the references for further research and development of the plants in Hypecoum L.

Progress of antibacterial activity and antibacterial mechanism of isoquinoline alkaloids / 中国中药杂志

This paper reviewed the antibacterial activity and structure-activity relationship of isoquinoline alkaloids, such as protoberberine, protopine, benzophenanthridine, aporphine, double benzyl isoquinoline, etc. The antibacterial mechanism of alkaloids were illustrated from cell wall and membrane damage, membrane permeability changes, related enzymes and efflux pump inhibition, influence of bacterial DNA and related protein synthesis and so on. In addition, this paper summarized the structure-activity relationship of isoquinoline alkaloids. In order to improve the screening efficiency of drug targets, the complementary effect of biological information science and combinatorial chemistry should be developed abundantly in the development of natural product. This paper will provide a theoretical reference for the research and development of new antibacterial agent.

Aldose Reductase Inhibitory Alkaloids from Corydalis ternata

A methanolic extract of Corydalis ternata having aldose reductase inhibitory activity was examined as a possible aldose reductase (ALR2) inhibitor, a key enzyme involved in diabetic complications. Seven alkaloids, tetrahydrocoptisine (1), corydaline (2), tetrahydropalmatine (3), isocorybulbine (4), corybulbine (5), dehydrocorydaline (6), and N-methyltetrahydroberbinium (7) were isolated from CHCl₃ fraction of C. ternata methanol extract. Among them, compounds 1, 5, and 7 exhibited 5.04 ± 1.97%, 5.00 ± 1.26%, and 1.80 ± 2.33% inhibitions, respectively at 40 µM. The activities of the single compounds were not comparable to that of the whole extract, suggesting that the whole combination of each single compound was responsible for the activity of the extract as shown in many cases of natural medicines. Even though this is the second report on aldose reductase inhibition activity of C. ternata, recombinant human aldose reductase was employed in this study unlike in the previous report. Furthermore, the aldose reductase inhibitory activities of isocorybulbine, corybulbine, and N-methyltetrahydroberbinium, to the best of our knowledge, were evaluated for the first time in this study. These results suggest a use of the extract of C. ternata for ameliorating diabetic complications.

Chemical Constituents of Plants from Tribe Chelidonieae and their Bioactivities / 中草药·英文版

The tribe Chelidonieae comprises 23 species of eight genera with an extensive distribution and a long medicinal usage history both in China and Western countries. A large number of chemical constituents have been isolated and identified from the species in tribe Chelidonieae, such as alkaloids, organic acids, and their derivatives, aromatics, triterpenoids, sterols, essential oils, and proteins, most of which possess a variety of bioactivities, especially for the antibacterial, anti-inflammation, antitumor, analgesia, anti-oxidation, and antiparasitic activity. Meanwhile, potential toxicities have been discovered in some constituents. Therefore, the species in tribe Chelidonieae have become a rich source for new drug discovery, biologic study, and mechanism research. This paper presents comprehensive information of the chemical constituents, pharmacological and toxicological research on the plants in tribe Chelidoieae, which is a reference for the plants in this tribe for further development. © 2014 Tianjin Press of Chinese Herbal Medicines.

Identification of isoquinoline alkaloids from Berberis microphylla by HPLC ESI-MS/MS / Identificación de alcaloides isoquinolínicos en Berberis microphylla G. Forst mediante CLAE IES-MS/MS

Berberis microphylla (G. Forst) is a native plant growing in Patagonia. In recent years Patagonia Berberis are becoming important due to their interesting biological properties related to their alkaloids content. The aim of this study was determine the distribution and proportion of isoquinoline alkaloids in leaves, stems and roots of B. microphylla collected in two different climatic zones from Chilean Patagonia. Using by HPLC ESI-MS/MS isocorydine, jatrorrhizine, palmatine, reticuline, scoulerine, tetrahydroberberine and thalifendine were detected for the first time in this specie, and the presence of allocryptopine, berberine, calafatine and protopine, previously isolated in B. microphylla was corroborated. The alkaloids profile showed differences of compounds in samples collected in two climatic zones, where more compounds were detected in plants from Lago Deseado than Cerro Sombrero. Furthermore, a greater number of alkaloids were found in stem and root extracts and berberine and thalifendine were detected in higher proportion in these structures.

Berberis microphylla (G. Forst) es un arbusto nativo que crece en la Patagonia. Actualmente, esta planta ha sido foco de estudio dada las propiedades biológicas que presenta, atribuidas principalmente al contenido de alcaloides. El objetivo de este estudio fue determinar la distribución y proporción de alcaloides isoquinolínicos en hojas, tallos y raíces de B. microphylla colectadas en dos zonas climáticas de la Patagonia chilena. Mediante CLAE IES-MS/MS se informa por primera vez la presencia de isocoridina jatrorrizina, palmatina, reticulina, escoulerina, tetrahidroberberina y talifendina en esta especie y se confirma la presencia de allocriptopina, berberina, calafatina y protopina, identificados previamente en B. microphylla. El perfil de alcaloides mostró diferencias en la presencia de compuestos en las muestras colectas en las dos zonas climáticas, observándose un mayor número de compuestos en plantas provenientes de Lago Deseado. Además, un mayor número de compuestos se identificó en extractos de tallos y raíces donde berberina y talifendina fueron detectados en mayor proporción.

Determination of Alkaloids in Honey by Dispersive Solid Phase Extraction and High Performance Liquid Chromatography-Tandem Mass Spectrometry / 分析化学

A method was developed for simultaneous determination of pyrrolizidine alkaloids and isoquinoline alkaloids in honey by dispersive solid phase extraction and high performance liquid chromatography-tandem mass spectrometry ( QuEChERS-HPLC-MS/MS) . The honey samples were extracted with acetonitrile solution and cleaned up with PSA absorbent. Agilent Poroshell 120 SB-C18 chromatographic column was used to separate alkaloids with high sensitivity and satisfactory resolution. The identification and quantification were achieved by using electrospray ionization in positive ion mode ( ESI+) with multiple reaction monitoring (MRM). Matrix-matched calibration curves with good correlation coefficients (R2>0. 99) were obtained in the concentration range of 0. 1-100 μg/L. The recoveries of the spiked samples at 1-100 μg/kg were in the range of 70% to 110% with the RSD of intra-day and inter-day lower than 15% and 20%, respectively. The limits of detection ( LOD) and limits of quantification ( LOQ) for all alkaloids were 0. 3 and 1. 0 μg/kg, respectively. This method was successfully applied to the simultaneous determination of pyrrolizidine alkaloids and isoquinoline alkaloids for quantification and confirmation in honey samples.

Comparison on in vitro hepatic metabolic characteristics of five kinds of alkaloids from Coptis chinensis / 中草药

Objective: To explore the in vitro hepatic metabolic selectivity of five kinds of isoquinoline alkaloids (with the similar structures) from Coptis chinensis in rats. Methods: Using the method of rat in vitro liver microsomes incubation model, the metabolic kinetics parameters Km, Vmax, and CLint for berberine, palmatine, coptisine, epiberberine, and jateorhizine were calculated by observing the influence of incubation time, protein concentration of liver microsomes, and substrate concentration on metabolic characteristics in liver. Results: The difference of in vitro hepatic metabolic kinetics parameters Km and CLint among five kinds of alkaloids from C. chinensis is statistically significant (P < 0.05). Conclusion: There is a significant selectivity in in vitro hepatic metabolism of five kinds of isoquinoline alkaloids from C. chinensis in rats.