Three new phenylpropanoids from the roots of Piper taiwanense and their inhibitory activities on platelet aggregation and Mycobacterium tuberculosis.

Bioassay-guided fractionation of the active AcOEt-soluble fraction from the roots of Piper taiwanense has led to the isolation of two new phenylpropanoids, taiwanensols A and B (1 and 2, resp.), a new natural product, taiwanensol C (3), and 3-acetoxy-4-hydroxy-1-allylbenzene (4). The compounds were obtained as two isomer mixtures (1/2 and 3/4, resp.). Their structures were elucidated by spectroscopic analyses, including 1D- and 2D-NMR spectroscopy and mass spectrometry, and by the comparison of their NMR data with those of related compounds. Compounds 1-4 were evaluated for their antiplatelet and antitubercular activities. The mixtures 1/2 and 3/4 showed potent inhibitory activities against platelet aggregation induced by collagen, with IC50 values of 35.2 and 8.8 µM, respectively. In addition, 1/2 and 3/4 showed antitubercular activities against Mycobacterium tuberculosis H37Rv, with MIC values of 30.0 and 48.0 µg/ml, respectively.

Microjaponin, a new dihydroagarofuranoid sesquiterpene from the stem of Microtropis japonica with antituberculosis activity.

A new dihydroagarofuran-based sesquiterpene, microjaponin (1), was isolated from the stem of Microtropis japonica. Its structure was determined by in-depth spectroscopic and mass-spectrometric analyses. Microjaponin (1) exhibited potent in vitro antituberculosis activity, with an MIC value of 12.5 µg/ml against Mycobacterium tuberculosis H37 Rv.

New pterosin sesquiterpenes and antitubercular constituents from Pteris ensiformis.

Two new pterosin sesquiterpenes, (2S)-13-hydroxypterosin A (1) and (2S,3S)-12-hydroxypterosin Q (2), were isolated from the whole plants of Pteris ensiformis, together with six known compounds. The structures of 1 and 2 were determined through extensive 1D/2D-NMR and MS analyses. Compound 2 exhibited antitubercular activity (MIC 6.25 µg/ml) against Mycobacterium tuberculosis H37 Rv in vitro.

Structural elucidation and bioactivity of biflavonoids from the stems of Wikstroemia taiwanensis.

Three new biflavonoids, wikstaiwanones A-C (1-3), along with four known compounds (4-7) were isolated from the stems of Wikstroemia taiwanensis (Thymelaeaceae). Their structures were elucidated by spectroscopic analysis. Compounds 4 and 5 showed antitubercular activity against Mycobacterium tuberculosis with MIC values of 15 µg/mL, respectively.

Use of inverse PCR for analysis of class 1 integrons carrying an unusual 3' conserved segment structure.

By using inverse PCR and DNA sequencing, 13 sul3-associated mutational integrons, 2 defective class 1 integrons, and 1 qnrB2-associated complex sul1-type class 1 integrons were identified in Salmonella enterica serovar Choleraesuis, Pseudomonas aeruginosa, and Enterobacter cloacae, respectively. In addition, conjugation and Southern hybridization demonstrated that unusual class 1 integrons were located on plasmids or integrated into chromosomal DNA. Thus, an inverse PCR assay can be a valuable tool for the analysis of unusual structures of the 3' conserved region of class 1 integrons.

Antitubercular chromones and flavonoids from Pisonia aculeata.

Three new chromones, pisonins A (1), B (2), and D (4), two new flavonoids, pisonivanone [(2S)-5,7,2'-trihydroxy-8-methylflavanone] (7) and pisonivanol [(2R,3R)-3,7-dihydroxy-5,6-dimethoxyflavanone] (8), one new isoflavonoid, pisonianone (5,7,2'-trihydroxy-6-methoxy-8-methylisoflavone) (9), and five compounds first isolated from nature, namely, pisonins C (3), E (5), and F (6), pisoniamide (10), and pisonolic acid (11), together with 18 known compounds have been isolated from the methanol extract of the combined stem and root of Pisonia aculeata. Among these isolates, 2, 7, 14, 16, and 19 exhibited antitubercular activities (MICs≤50.0 µg/mL) against Mycobacterium tuberculosis H37Rv in vitro.

Antitubercular resorcinol analogs and benzenoid C-glucoside from the roots of Ardisia cornudentata.

Bioassay-guided fractionation of the roots of Ardisia cornudentata Mez (Myrsinaceae) led to the isolation of three new compounds, 3-methoxy-2-methyl-5-pentylphenol (1), 3-methoxy-2-methyl-5-(1'-ketopentyl)phenol (2), and cornudoside (3), together with twenty-six known compounds. Their structures were elucidated by analysis of spectroscopic data. Thirteen of these isolates, 1, 2, 4- 6, 9- 15, and 21 showed antitubercular activities against Mycobacterium tuberculosis H37R (V) IN VITRO, with MIC values of 2.5-60 µg/mL. Two alkyl benzoquinones, ardisianone (7) and cornudentanone ( 8), were reported for their selective cytotoxic activity against the NCI-H460 cancer cell line (IC (50) values of 2.3, 2.5 µg/mL).

Chemical constituents and antitubercular activity of Formosan Pisonia umbellifera.

Bioassay-guided fractionation of the methanolic extract of the stem of Pisonia umbellifera (Nyctaginaceae) afforded the three new compounds, secopisonic acid (1), 6,8-dimethylisogenistein (2), and (+)- ENT-ficusol (3), and four first isolates from nature, pisoninol I (4), pisoninol II (5), pisoquinoline (6), and pisodienone (7), together with fifteen known compounds. Their structures were elucidated by analysis of spectroscopic data. Seven of these isolates, 3, 7, 12, 16, 18, 20, and 21 showed antitubercular activities against Mycobacterium tuberculosis H37R (V) in vitro, with MIC values ≤ 50 µg/mL.

Secondary metabolites from the root wood of Zanthoxylum wutaiense and their antitubercular activity.

Bioassay-guided fractionation of the root wood of Zanthoxylum wutaiense led to the isolation of five new compounds, wutaipyranol A (1), 8-methoxywutaipyranol A (2), demethoxywutaiensal (3), demethoxywutaiensol (4), and dihydrodemethoxywutaiensol (5), together with six known compounds. Their structures were elucidated by 1D- and 2D-NMR, as well as MS analyses. Among the isolates, wutaipyranol A (1), 8-methoxywutaipyranol A (2), and demethoxywutaiensal (3) exhibited antitubercular activities against Mycobacterium tuberculosis H(37) Rv in vitro, with MIC values of 52.4, 55.6, and 45.8 µg/ml, respectively.

New flavanones from the leaves of Cryptocarya chinensis and their antituberculosis activity.

Four new flavanones, cryptoflavanones A-D (1-4, resp.), together with eight known compounds, were isolated from the leaves of Cryptocarya chinensis. The structures of these new compounds were determined by spectral analyses. Among the isolated compounds, pinocembrin (5) and cryptocaryone (6) exhibited antituberculosis activity against Mycobacterium tuberculosis H(37) Rv strain in vitro with MIC values of 3.5 and 25.0 µg/ml, respectively.

Secondary metabolites from the roots of Litsea hypophaea and their antitubercular activity.

Bioassay-guided fractionation of the roots of Litsea hypophaea led to the isolation of seven new butanolides, namely, litseakolides H-N (1-7), all with the 3R,4S configuration, as well as three new biarylpropanoids, hypophaone (8), hypophaol (9), and hypophane (10), and 15 known compounds. The structures of 1-10 were determined by means of spectroscopic analysis. Litseakolide L (5) and N-trans-feruloylmethoxytyramine (11) showed antitubercular activity against Mycobacterium tuberculosis strain H(37)Rv, with MIC values of 25 and 1.6 microg/mL, respectively.

Secondary metabolites and antimycobacterial activities from the roots of Ficus nervosa.

Bioassay-guided fractionation of the active AcOEt-soluble layer led to the isolation of two new pyranocoumarins, 3-hydroxyxanthyletin (1) and 3-methoxyxanthyletin (2), along with 22 known compounds including four simple coumarins, i.e., xanthyletin (3), umbelliferone (4), scopoletin (5), and (+)-(S)-marmesin (6); nine flavonoids, i.e., carpachromene (7), parvisoflavone B (8), alpinumisoflavone (9) genistein (10), 2'-hydroxygenistein (11), prunetin (12), cajanin (13), apigenin (14), and (2S)-naringenin (15); three benzenoids, i.e., 4-hydroxybenzaldehyde (16), vanillin (17), and (S)-lasiodiplodin (18); five steroids, i.e., ergosterol peroxide (19), a mixture of 6beta-hydroxystigmast-4-en-3-one (20) and 6beta-hydroxystigmasta-4,22-dien-3-one (21), and a mixture of beta-sitosterol (22) and stigmasterol (23); and one triterpenoid, i.e., oleanolic acid (24) from the roots of Ficus nervosa. Their structures were elucidated on the basis of extensive 1D- and 2D-NMR as well as MS analyses. Among these isolates, 3-hydroxyxanthyletin (1), genistein (10), prunetin (12), and (2S)-naringenin (15) showed antimycobacterial activities against Mycobacterium tuberculosis H(37)R(V) in vitro with MIC values of 16, 35, 30, and < or =2.8 microg/ml, respectively.

A new long-chain alkene and antituberculosis constituents from the leaves of Pourthiaea lucida.

A new long-chain alkene, dotriacont-1-ene (1), was isolated from the leaves of Pourthiaea lucida, together with twelve known compounds. The structure of this new compound was determined by NMR and mass-spectrometric analyses. Among the isolated compounds, alpha-tocospiro A (2), alpha-tocopheryl quinone (4), and (E)-phytol (5) exhibited antituberculosis activities (MICs

A novel dimeric coumarin analog and antimycobacterial constituents from Fatoua pilosa.

One novel dimeric coumarin analog, fatouapilosin (1), together with 18 known compounds, have been isolated from the whole plants of Fatoua pilosa. The structures of these isolates were elucidated by means of spectroscopic techniques (UV, IR, MS, 1H- and 13C-NMR, DEPT, COSY, NOESY, HSQC, HMBC, and MS analyses). Among the tested compounds 2-14, scopoletin (3), isobavachalcone (12), and (E)-1-[2,4-dihydroxy-3-(3-methylbut-2-enyl)phenyl]-3-(2,2-dimethyl-8-hydroxy-2H-benzopyran-6-yl)prop-2-en-1-one (14) exhibited the strongest antimycobacterial activities against Mycobacterium tuberculosis H(37)Rv, with MIC values of 42, 18, and 30 microg/ml, respectively.

Evaluation of reverse transcription loop-mediated isothermal amplification in conjunction with ELISA-hybridization assay for molecular detection of Mycobacterium tuberculosis.

Traditional culture, followed by a panel of biochemical tests for the diagnosis of tuberculosis (TB), is time-consuming, and rapid identification of Mycobacterium tuberculosis is crucial for the early administration of appropriate therapy. In this study, the reverse transcription loop-mediated isothermal amplification combined with enzyme-linked immunosorbent hybridization (RT-LAMP-ELISA-hybridization) assay has been designed for the rapid detection of 16S rRNA in clinical isolates of M. tuberculosis. This assay reproducibly detected a single copy, as opposed to 2000 copies of MTB 16S rRNA detected by conventional gel electrophoresis. Among the 150 specimens of sputum analysed, RT-LAMP-ELISA-hybridization assay had a sensitivity of 94.1% in the culture method, compared to the Amplified M. tuberculosis Direct Test (AMTD), 91.1% and the 88.2% sensitivity of acid-fast staining. Furthermore, RT-LAMP-ELISA-hybridization assay is more cost-effective when compared to the real-time TaqMan RT-PCR and AMTD assays. In conclusion, our results suggest that the RT-LAMP-ELISA-hybridization assay is a highly sensitive, low cost diagnostic tool useful for the rapid and accurate direct diagnosis of sputum specimens, and is suitable for routine clinical use.

seco-Abietane diterpenoids, a phenylethanoid derivative, and antitubercular constituents from Callicarpa pilosissima.

Six new compounds, including five new seco-abietane diterpenoids, 12-deoxy-seco-hinokiol methyl ester (1), 12-deoxy-11,12-dihydro-seco-hinokiol methyl ester (2), callicarpic acid A (3), 9alpha-hydroxycallicarpic acid A (4), and callicarpic acid B (5), and a new phenylethanoid derivative, 4-hydroxyphenethyl tetradecanoate (6), have been isolated from the leaves and twigs of Callicarpa pilosissima, together with 14 known compounds (7-20). The structures of these new compounds were determined through analyses of physical data. 12-Deoxy-11,12-dihydro-seco-hinokiol methyl ester (2), callicarpic acid B (5), and alpha-tocopherol trimer B (15) exhibit antitubercular activities (MICs

Endiandric Acid Analogues from the Roots of Beilschmiedia erythrophloia.

Investigation of the roots of Beilschmiedia erythrophloia has led to the isolation of seven new endiandric acid analogues, erythrophloins A-F (1-6) and beilcyclone A (7), together with 11 known compounds. The structures of 1-7 were determined using spectroscopic techniques. Two constituents, erythrophloin C (3) and suberosol B (8), exhibited antitubercular activity against Mycobacterium tuberculosis H37Rv, showing MIC values of 50 and 28.9 microg/mL, respectively.

Molecular characterisation of the metallo-beta-lactamase genes in imipenem-resistant Gram-negative bacteria from a university hospital in southern Taiwan.

In this study, 260 non-replicate imipenem-resistant Gram-negative bacteria isolated between January 2002 and December 2006 were subjected to a screening test for detection of metallo-beta-lactamase (MBL) using the Etest containing imipenem and ethylene diamine tetra-acetic acid (EDTA). Among the 260 strains, 123 (47.3%) appeared to produce MBL. Of these 123 strains, 113 (91.9%) were found by polymerase chain reaction (PCR) to carry MBL genes of types blaVIM-2, blaVIM-3, blaVIM-11 (blaVIM-11a), blaIMP-8 and novel blaIMP-24. One strain of Serratia marcescens harboured two MBL genes (blaVIM-11 and blaIMP-8) simultaneously. Of the 123 strains, 116 strains (94.3%) carrying the intI1 gene and 21 strains carrying integron-associated blaVIM-3, blaVIM-11 and blaIMP-8 genes were identified among Acinetobacter baumannii, Pseudomonas aeruginosa, Acinetobacter haemolyticus and S. marcescens. Using pulsed-field gel electrophoresis (PFGE) and Southern hybridisation with the blaVIM gene probe for I-CeuI-digested genomic DNA, P. aeruginosa 9527 strain harboured two class 1 integron-associated MBL genes in the chromosome, including blaVIM-3-orf2-aacA4 and novel bla(VIM-3)-orf2-aacA4-aadB-aacA4. This is the first description of the blaVIM-11 gene spreading among P. aeruginosa and A. baumannii strains in southern Taiwan. This finding suggests that clinical spread of this blaVIM-11 gene is a matter of great concern for carbapenem resistance in southern Taiwan.

Constituents of the root wood of Zanthoxylum wutaiense with antitubercular activity.

Bioassay-guided fractionation of the root wood of Zanthoxylum wutaiense led to the isolation of 11 new compounds, wutaiensol methyl ether (1), demethoxywutaiensol methyl ether (2), methyl wutaiensate (3), methyl 7-hydroxyanodendroate (4), methyl 7-methoxyanodendroate (5), wutaifuranol (6), 7-methoxywutaifuranol (7), 7-methoxywutaifuranal (8), methyl wutaifuranate (9), methyl 7-methoxybenzofuran-5-carboxylate (10), and wutaipyranol (12), together with another 37 known compounds, of which one, 7-methoxybenzofuran-5-carboxaldehyde (11), was not previously known as a plant constituent. The structures of these isolates were identified by means of spectroscopic analysis. Five of these isolates were found to be antitubercular constituents, namely, methyl 7-methoxyanodendroate (5), 7-methoxywutaifuranal (8), wutaiensal (13), dictamnine (14), and gamma-fagarine (15), which exhibited antitubercular activity against Mycobacterium tuberculosis H37Rv, showing MIC values of 35, 35, 30, 30, and 30 microg/mL, respectively.

Dihydroagarofuranoid sesquiterpenes, a lignan derivative, a benzenoid, and antitubercular constituents from the stem of Microtropis japonica.

Four new compounds, including two new dihydroagarofuranoid sesquiterpenes, 8-benzoyloxymutangin (1) and 15-acetoxyorbiculin G (2), a new lignan derivative, 9,9'- O-di-(Z)-feruloyl-(-)-secoisolariciresinol (3), and a new benzenoid, 5'-methoxyevofolin B (4), have been isolated from the stem of Microtropis japonica, together with 20 known compounds (5- 24). 3-Ethoxy-4-hydroxybenzaldehyde (5) was identified from a natural source for the first time. The structures of these new compounds were determined through analyses of physical data. 15-Acetoxyorbiculin G (2), celahin C (6), and salasol A (7) exhibit antituberculosis activities (MICs < or = 39.6 microM) against Mycobacterium tuberculosis H 37Rv in vitro.