arteannuin-b and artemisinin

In recent years, C-H bond functionalization has emerged as a pivotal tool for late-stage functionalization of complex natural products for the synthesis of potent biologically active derivatives. Artemisinin and its C-12 functionalized semi-synthetic derivatives are well-known clinically used anti-malarial drugs due to the presence of the essential 1,2,4-trioxane pharmacophore. However, in the wake of parasite developing resistance against artemisinin-based drugs, we conceptualized the synthesis of C-13 functionalized artemisinin derivatives as new antimalarials. In this regard, we envisaged that artemisinic acid could be a suitable precursor for the synthesis of C-13 functionalized artemisinin derivatives. Herein, we report C-13 arylation of artemisinic acid, a sesquiterpene acid and our attempts towards synthesis of C-13 arylated artemisinin derivatives. However, all our efforts resulted in the formation of a novel ring-contracted rearranged product. Additionally, we have extended our developed protocol for C-13 arylation of arteannuin B, a sesquiterpene lactone epoxide considered to be the biogenetic precursor of artemisinic acid. Indeed, the synthesis of C-13 arylated arteannuin B renders our developed protocol to be effective in sesquiterpene lactone as well.

Topics: Alkenes; Antimalarials; Artemisinins; Lactones; Sesquiterpenes

Host inflammatory responses are key to protection against injury; however, persistent inflammation is detrimental and contributes to morbidity and mortality. Herein, we demonstrated the anti-inflammatory role of Arteannuin-B (

Topics: Animals; Anti-Inflammatory Agents; Down-Regulation; Lipopolysaccharides; Macrophages; Mice; Mice, Inbred BALB C; NF-kappa B; p38 Mitogen-Activated Protein Kinases

Topics: Artemisia annua; Artemisinins; Bryopsida; Plant Proteins; Plants, Genetically Modified

A fast, simple, efficient, and high-throughput analytical protocol using deep eutectic solvents (DES) for mechanochemical extraction (MCE) combined with direct analysis in real time mass spectrometry (DART-MS) was developed to quantify heat-labile bioactive compounds artemisinin (AN), arteannuin B, and artemisinic acid from Aretemisia annua. MCE is performed at room temperature, and target analytes are released into DESs within seconds; this method demonstrated multiple advantages over traditional extraction methods and organic solvents. DART-MS was then used for the structure confirmation and quantification for the three artemisinin major components extracted from plants of five locations. Liquid chromatography (LC) measurements were performed as well for results verification and comparison, and the amounts obtained were consistent between the two techniques. DART-MS showed advantages in simplicity, low limit of detection (5-15 ng mL

Topics: Artemisia annua; Artemisinins; Limit of Detection; Mass Spectrometry; Solid Phase Extraction; Solvents

We recently characterized a gene-terpene network that is associated with artemisinin biosynthesis in self-pollinated (SP) Artemisia annua, an effective antimalarial plant. We hypothesize that an alteration of gene expression in the network may improve the production of artemisinin and its precursors. In this study, we cloned an isopentenyl pyrophosphate isomerase (IPPI) cDNA, AaIPPI1, from Artemisia annua (Aa). The full-length cDNA encodes a type-I IPPI containing a plastid transit peptide (PTP) at its amino terminus. After the removal of the PTP, the recombinant truncated AaIPPI1 isomerized isopentenyl pyrophosphate (IPP) to dimethyl allyl pyrophosphate (DMAPP) and vice versa. The steady-state equilibrium ratio of IPP/DMAPP in the enzymatic reactions was approximately 1:7. The truncated AaIPPI1 was overexpressed in the cytosol of the SP A. annua variety. The leaves of transgenic plants produced approximately 4% arteannuin B (g g

Topics: Artemisia annua; Artemisinins; Carbon-Carbon Double Bond Isomerases; Cytosol; Hemiterpenes; Plant Proteins; Plants, Genetically Modified

Daodi-herb is a part of Chinese culture, which has been naturally selected by traditional Chinese medicine clinical practice for many years. Sweet wormwood herb is a kind of Daodi-herb, and comes from Artemisia annua L. Artemisinin is a kind of effective antimalarial drug being extracted from A. annua. Because of artemisinin, Sweet wormwood herb earns a reputation. Based on the Pharmacopoeia of the People's Republic of China (PPRC), Sweet wormwood herb can be used to resolve summerheat-heat, and prevent malaria. Besides, it also has other medical efficacies. A. annua, a medicinal plant that is widely distributed in the world contains many kinds of chemical composition. Research has shown that compatibility of artemisinin, scopoletin, arteannuin B and arteannuic acid has antimalarial effect. Compatibility of scopoletin, arteannuin B and arteannuic acid is conducive to resolving summerheat-heat. Chemical constituents in A. annua vary significantly according to geographical locations. So, distribution of A. annua may play a key role in the characteristics of efficacy and chemical constituents of Sweet wormwood herb. It is of great significance to study this relationship.. We mainly analyzed the relationship between the chemical constituents (arteannuin B, artemisinin, artemisinic acid, and scopoletin) with special efficacy in A. annua that come from different provinces in china, and analyzed the relationship between chemical constituents and spatial distribution, in order to find out the relationship between efficacy, chemical constituents and distribution.. A field survey was carried out to collect A. annua plant samples. A global positioning system (GPS) was used for obtaining geographical coordinates of sampling sites. Chemical constituents in A. annua were determined by liquid chromatography tandem an atmospheric pressure ionization-electrospray mass spectrometry. Relationship between chemical constituents including proportions, correlation analysis (CoA), principal component analysis (PCA) and cluster analysis (ClA) was displayed through Excel and R software version2.3.2(R), while the one between efficacy, chemical constituents and spatial distribution was presented through ArcGIS10.0, Excel and R software.. According to the results of CoA, arteannuin B content presented a strong positive correlation with artemisinic acid content (p = 0), and a strong negative correlation with artemisinin content (p = 0). Scopoletin content presented a strong positive correlation with artemisinin content (p = 0), and a strong negative correlation with artemisinic acid content (p = 0). According to the results of PCA, the first two principal components accounted for 81.57% of the total accumulation contribution rate. The contribution of the first principal component is about 45.12%, manly including arteannuin B and artemisinic acid. The contribution of the second principal component is 36.45% of the total, manly including artemisinin and scopoletin. According to the ClA by using the principal component scores, 19 provinces could be divided into two groups. In terms of provinces in group one, the proportions of artemisinin are all higher than 80%. Based on the results of PCA, ClA, percentages and scatter plot analysis, chemical types are defined as "QHYS type", "INT type" and "QHS type.". As a conclusion, this paper shows the relationship between efficacy, chemical constituents and distribution. Sweet wormwood herb with high arteannuin B and artemisinic acid content, mainly distributes in northern China. Sweet wormwood herb with high artemisinin and scopoletin content has the medical function of preventing malaria, which mainly distributes in southern China. In this paper, it is proved that Sweet wormwood Daodi herb growing in particular geographic regions, has more significant therapeutical effect and higher chemical constituents compared with other same kind of CMM. And also, it has proved the old saying in China that Sweet wormwood Daodi herb which has been used to resolve summerheat-heat and prevent malaria, which distributed in central China. But in modern time, Daodi Sweet wormwood herb mainly has been used to extract artemisinin and prevent malaria, so the Daod-region has transferred to the southern China.

Topics: Antimalarials; Artemisia annua; Artemisinins; China; Cluster Analysis; Plant Extracts; Principal Component Analysis; Scopoletin; Software

The artemisinic aldehyde double bond reductase (DBR2) plays an important role in the biosynthesis of the antimalarial artemisinin in Artemisia annua. Artemisinic aldehyde is reduced into dihydroartemisinic aldehyde by DBR2. Artemisinic aldehyde can also be oxidized by amorpha-4,11-diene 12-hydroxylase and/or aldehyde dehydrogenase 1 to artemisinic acid, a precursor of arteannuin B. In order to better understand the effects of DBR2 expression on the flow of artemisinic aldehyde into either artemisinin or arteannuin B, we determined the content of dihydroartemisinic aldehyde, artemisinin, artemisinic acid and arteannuin B content of A. annua varieties sorted into two chemotypes. The high artemisinin producers (HAPs), which includes the '2/39', 'Chongqing' and 'Anamed' varieties, produce more artemisinin than arteannuin B; the low artemisinin producers (LAPs), which include the 'Meise', 'Iran#8', 'Iran#14', 'Iran#24' and 'Iran#47' varieties, produce more arteannuin B than artemisinin. Quantitative PCR showed that the relative expression of DBR2 was significantly higher in the HAP varieties. We cloned and sequenced the promoter of the DBR2 gene from varieties of both the LAP and the HAP groups. There were deletions/insertions in the region just upstream of the ATG start codon in the LAP varities, which might be the reason for the different promoter activities of the HAP and LAP varieties. The relevance of promoter variation, DBR2 expression levels and artemisinin biosynthesis capabilities are discussed and a selection method for HAP varieties with a DNA marker is suggested. Furthermore, putative cis-acting regulatory elements differ between the HAP and LAP varieties.

Topics: Antimalarials; Artemisia annua; Artemisinins; Base Sequence; DNA, Plant; Genes, Plant; Oxidoreductases; Plant Proteins; Plants, Medicinal; Polymerase Chain Reaction; Promoter Regions, Genetic; Species Specificity

Malaria and dengue are the two most important vector-borne human diseases caused by mosquito vectors Anopheles stephensi and Aedes aegypti, respectively. Of the various strategies adopted for eliminating these diseases, controlling of vectors through herbs has been reckoned as one of the important measures for preventing their resurgence. Artemisia annua leaf chloroform extract when tried against larvae of A. stephensi and A. aegypti has shown a strong larvicidal activity against both of these vectors, their respective LC50 and LC90 values being 0.84 and 4.91 ppm for A. stephensi and 0.67 and 5.84 ppm for A. aegypti. The crude extract when separated through column chromatography using petroleum ether-ethyl acetate gradient (0-100%) yielded 76 fractions which were pooled into three different active fractions A, B and C on the basis of same or nearly similar R f values. The aforesaid pooled fractions when assayed against the larvae of A. stephensi too reported a strong larvicidal activity. The respective marker compound purified from the individual fractions A, B and C, were Artemisinin, Arteannuin B and Artemisinic acid, as confirmed and characterized through FT-IR and NMR. This is our first report of strong mortality of A. annua leaf chloroform extract against vectors of two deadly diseases. This technology can be scaled up for commercial exploitation.

Topics: Aedes; Animals; Anopheles; Artemisia annua; Artemisinins; Insect Vectors; Insecticides; Larva; Mosquito Control; Plant Extracts; Plant Leaves; Spectroscopy, Fourier Transform Infrared

The objective of this study is to develop a sensitive and reliable high-performance liquid chromatography mass spectrometry (LC-MS) method for simultaneous determination of artemisinin, arteannuin B, artemisic acid, and scopoletin, and study the pharmacokinetics of the four constituents in mouse serum after oral administration of the four components to mice. The analytical column used was Agilent Zorbax SB-C18 (2.1 mm x 150 mm, 5 mm). The mobile phase was acetonitrile: 0.5% acetic acid (60: 40) and the flow rate was 0.3 mL x min(-1). The temperature of the column was 40.0 degrees C. In this condition, we established an analysis method to simultaneously determine the four components. A sensitive and specific liquid chromatography-mass spectrometric (LC-MS) method was developed and validated for the determination of artemisin in derivatives in mice plasma. The method we established has a linear range of 5-3 000 μg x L(-1) with a good sensitivity and specificity for all of the four components. This method is simple, rapid, accurate and suitable for the determination of the content of the four compounds.

Topics: Animals; Artemisinins; Chromatography, High Pressure Liquid; Dose-Response Relationship, Drug; Male; Mice; Reproducibility of Results; Scopoletin; Spectrometry, Mass, Electrospray Ionization

Artemisia annua hot water infusion (tea) has been used in in vitro experiments against P. falciparum malaria parasites to test potency relative to equivalent pure artemisinin. High performance liquid chromatography (HPLC) and mass spectrometric analyses were employed to determine the metabolite profile of tea including the concentrations of artemisinin (47.5±0.8 mg L(-1)), dihydroartemisinic acid (70.0±0.3 mg L(-1)), arteannuin B (1.3±0.0 mg L(-1)), isovitexin (105.0±7.2 mg L(-1)) and a range of polyphenolic acids. The tea extract, purified compounds from the extract, and the combination of artemisinin with the purified compounds were tested against chloroquine sensitive and chloroquine resistant strains of P. falciparum using the DNA-intercalative SYBR Green I assay. The results of these in vitro tests and of isobologram analyses of combination effects showed mild to strong antagonistic interactions between artemisinin and the compounds (9-epi-artemisinin and artemisitene) extracted from A. annua with significant (IC50 <1 μM) anti-plasmodial activities for the combination range evaluated. Mono-caffeoylquinic acids, tri-caffeoylquinic acid, artemisinic acid and arteannuin B showed additive interaction while rosmarinic acid showed synergistic interaction with artemisinin in the chloroquine sensitive strain at a combination ratio of 1:3 (artemisinin to purified compound). In the chloroquine resistant parasite, using the same ratio, these compounds strongly antagonised artemisinin anti-plasmodial activity with the exception of arteannuin B, which was synergistic. This result would suggest a mechanism targeting parasite resistance defenses for arteannuin B's potentiation of artemisinin.

Topics: Antimalarials; Artemisia annua; Artemisinins; Cinnamates; Depsides; Drug Synergism; Plant Extracts; Plasmodium falciparum; Rosmarinic Acid

To establish an HPLC-UV-ELSD method for the determination of the content of artemisinin, arteannuin B and artemisinic acid in Herba Artemisiae Annuae. The analytical column was Nucleodur RP-C18 (250 mm x 4.6 mm, 5 microm ID). The mobile phase was acetonirile-0.1% acetic acid (50: 50) and the flow rate was 1.0 mL x min(-1) with a UV detector for artemisinin, the detection wavelength at 209 nm, and the evaporative light-scattering detector (ELSD) for arteannuin B and artemisinic acid, the drift tube temperature: 50 degrees C, the nitrogen flow rate 30 psi and the gain was 50. The resolution of artemisinin, arteannuin B and artemisinic acid was good. The linear calibration curves were obtained over the range of 0.52 - 2.6 microg for artemisinin (r = 0.999 4, n = 5), 0.022 - 4.4 microg for artemisinin B (r = 0.999 9, n = 5) and 0.203 - 8.12 microg for artemisinic acid (r = 0.999 8, n = 5), separately. The mean recoveries of the three compounds were 99.45%, 102.37% and 101.10% with RSD of 2.3%, 1.7% and 0.79%, respectively. This method is simple, rapid, accurate and suitable for the determination of the content of the three compounds in the herbs.

Topics: Artemisia annua; Artemisinins; Chromatography, High Pressure Liquid; Light; Plant Components, Aerial; Plants, Medicinal; Reproducibility of Results; Scattering, Radiation; Sensitivity and Specificity; Spectrophotometry, Ultraviolet

A rapid and simple RP-TLC method for simultaneous quantification of pharmacologically important sesquiterpene artemisinin (AM) together with its precursors arteannuin-B (AB) and artemisinic acid (AA) in the inflorescence part of Artemisia annua plant has been developed. The RP-TLC of sesquiterpenes was performed on RP-18 F254 S thin-layer chromatographic plates by developing in mobile phase, containing 0.2% TFA in water/ACN (35:65, v/v). The densitometric determination of AM, AB and AA was carried out after derivatization with anisaldehyde reagent at 426 nm in absorption-reflectance mode.

Topics: Antimalarials; Artemisia annua; Artemisinins; Chromatography, Thin Layer; Densitometry; Molecular Structure; Plant Preparations; Sesquiterpenes

The protein involved in the conversion of arteannuin B to artemisinin has been purified from the leaves of Artemisia annua. The pure protein found to be homogenous on Native gel electrophoresis showed two major bands of 21 and 11 kDa on 12% SDS-PAGE. Molecular weight estimation of native protein indicated an apparent molecular mass of 66,000 Daltons. This protein is able to achieve 58% conversion. It has a K(m) of 0.5 mM for arteannuin B and a pH optima between 7.0-7.2. It is maximally active at 30 degrees C.

Topics: Artemisia; Artemisinins; Biotransformation; Chemical Fractionation; Electrophoresis, Polyacrylamide Gel; Enzymes; Hydrogen-Ion Concentration; Kinetics; Plant Proteins; Plants, Medicinal; Sesquiterpenes; Temperature

A series of artemisinin-related endoperoxides was tested for cytotoxicity to Ehrlich ascites tumor (EAT) cells using the microculture tetrazolium (MTT) assay. Artemisinin [1] had an IC50 value of 29.8 microM. Derivatives of dihydroartemisinin [2], being developed as antimalarial drugs (artemether [3], arteether [4], sodium artesunate [5], artelinic acid [6], and sodium artelinate [7]), exhibited a somewhat more potent cytotoxicity. Their IC50 values ranged from 12.2 to 19.9 microM. The presence of an exocyclic methylene fused to the lactone ring, as for artemisitene [9], led to higher cytotoxicity than 1. From the two epimeric 11-hydroxyartemisinin derivatives, the R form 12 showed a considerably higher cytotoxicity than the S form 13. Opening of the lactone ring of 1 dramatically reduced the cytotoxicity. The ether dimer 8 of 2 was the most potent cytotoxic agent, its IC50 being 1.4 microM. The variations in cytotoxicity between the structurally related compounds mostly correlated well with the theoretical capacity of radical formation and stabilization. In some cases lipophilicity or the presence of an electrophilic moiety seemed to have a determinant influence on cytotoxicity. The artemisinin-related endoperoxides showed cytotoxicity to EAT cells at higher concentrations than those needed for in vitro antimalarial activity, as reported in the literature.

Topics: Animals; Antineoplastic Agents, Phytogenic; Artemisinins; Carcinoma, Ehrlich Tumor; Cell Survival; Chemical Phenomena; Chemistry, Physical; Cisplatin; Doxorubicin; Peroxides; Sesquiterpenes; Structure-Activity Relationship; Tetrazolium Salts; Tumor Cells, Cultured

Arteannuin B, which co-occurs with artemisinin, the potent antimalarial principle of the Chinese medicinal herb Artemisia annua (Asteraceae), has been converted to the latter using crude and semi-purified cell-free extracts of the leaf homogenates of the plant. Detection procedures to quantitate this bioconversion, including one that is novel which uses gcms, are detailed.

Topics: Artemisinins; Cell-Free System; Cells, Cultured; Chromatography, Thin Layer; Medicine, Chinese Traditional; Plants; Plants, Medicinal; Sesquiterpenes; Spectrophotometry, Ultraviolet; Ultrafiltration