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Xiaojiang Hao - One of the best experts on this subject based on the ideXlab platform.
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Unprecedented Quassinoids with Promising Biological Activity from Harrisonia perforata
Angewandte Chemie (International ed. in English), 2015Co-Authors: Xin Fang, Yu Zhang, Qian Qian Chen, Qi Tai Zheng, Xiaojiang HaoAbstract:Perforalactone A (1), a new 20S Quassinoid with a unique cagelike 2,4-dioxaadamantane ring system and a migrated side chain, was isolated from the plant Harrisonia perforata together with two biosynthetically related new Quassinoids. The structures of these natural products were elucidated by NMR spectroscopy, X-ray diffraction analysis, computational modeling, and the CD excitation chirality method. The compounds exhibited notable biological properties, including insecticidal activity against Aphis medicaginis Koch and antagonist activity at the nicotinic acetylcholine receptor of Drosophila melanogaster. The structural features of these compounds may be related to their promising biological characteristics. Their biosynthesis and an alternative origin of Quassinoid-type natural products are also discussed.
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anti tobacco mosaic virus tmv Quassinoids from brucea javanica l merr
Journal of Agricultural and Food Chemistry, 2010Co-Authors: Xiaohui Yan, Jia Chen, Jiahong Dong, Peng Sang, Xin Fang, Zhongkai Zhang, Yuehu Wang, Xiaojiang HaoAbstract:Two new Quassinoids, javanicolide E (1) and javanicolide F (2), along with fifteen known C-20 Quassinoids were isolated from the seeds of Brucea javanica (L.) Merr. The antitobacco, mosaic virus (TMV) activity of these Quassinoids was screened by the conventional half-leaf and leaf-disk method along with Western blot analysis. All of the seventeen Quassinoids showed potent anti-TMV activity. Among them, eight compounds, brusatol (3), bruceine B (4), bruceoside B (5), yadanzioside 1 (6), yaclanzioside L (7), bruceine D (8), yadanziolide A (9), and aglycone of yadanziolide D (17), showed strong antiviral activities, with IC(50) values in the range of 3.42-5.66 mu M, and were much more effective than the positive control, ningnanmycin (IC(50) = 117.3 mu M). The antiviral structure-activity relationships of Quassinoids against TMV were also discussed.
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tobacco mosaic virus tmv inhibitors from picrasma quassioides benn
Journal of Agricultural and Food Chemistry, 2009Co-Authors: Jia Chen, Xiaohui Yan, Jiahong Dong, Peng Sang, Xin Fang, Zhongkai Zhang, Xiaojiang HaoAbstract:To investigate natural inhibitors against tobacco mosaic virus (TMV) from plants, 10 known β-carboline alkaloids and one Quassinoid have been isolated from MeOH extract of the wood of Picrasma quassioides Benn. These compounds were screened for their inhibitory activities against tobacco mosaic virus (TMV). The activity of each compound against TMV infection and replication was tested using a half-leaf assay method, a leaf-disk method, and Western blotting analyses. All of the β-carboline alkaloids showed moderate anti-TMV activities and exhibited synergistic effects when combined with the Quassinoid nigakilactone B (11). To our knowledge, this is the first report on anti-TMV activity of β-carbolines and their synergistic effects against TMV when combined with a Quassinoid.
Kit-lam Chan - One of the best experts on this subject based on the ideXlab platform.
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urinary nmr based metabolomic analysis of rats possessing variable sperm count following orally administered eurycoma longifolia extracts of different Quassinoid levels
Journal of Ethnopharmacology, 2016Co-Authors: Forough Ebrahimi, Baharudin Ibrahim, Chinhoe Teh, Vikneswaran Murugaiyah, Kit-lam ChanAbstract:Abstract Ethnopharmacological relevance Eurycoma longifolia (Tongkat Ali, TA) roots have been ethnically used as a remedy to boost male sexual desire, libido, energy and fertility. Aim of the study The study evaluated the effect of TA extracts with different Quassinoid levels on rats sperm count and examined corresponding post-treatment urinary metabolic changes. Materials and methods Twenty-four male Sprague–Dawley rats, categorized into 4 groups of 6 rats each, were orally administered for 48 days with water for the control (group 1), 125 mg/kg of TA water extract (TAW, group 2), 125 mg/kg of TA Quassinoid-poor extract (TAQP, group 3) and 21 mg/kg of TA Quassinoid-rich extract (TAQR, group 4). Upon completion of the 48-day treatment, the urine samples were analyzed by NMR and the animals were subsequently sacrificed for sperm count analysis. The urine profiles were categorized according to sperm count level. Results The results showed that the sperm count in TAW- and TAQR-treated groups was significantly higher compared to the TAQP-administered and control groups. The orthogonal partial least squares discriminant analysis (OPLS-DA) model indicated a clear separation among the urine profiles with respect to sperm count level. Urine 1H-NMR profiles of the high-sperm count group contained higher concentrations of trigonelline, alanine, benzoic acid and higher intensity of a signal at 3.42 ppm, while ethanol was at higher concentration in the normal-sperm count group. Conclusions The results proved the efficacy of Quassinoids on sperm count increase in rats and provided quantitative markers in urine suitable for analysis of sperm profile and male fertility status.
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acute reproductive toxicity and two generation teratology studies of a standardized Quassinoid rich extract of eurycoma longifolia jack in sprague dawley rats
Phytotherapy Research, 2014Co-Authors: Prashanta Kumar Das, Binseng Low, Kit-lam ChanAbstract:The roots of Eurycoma longifolia Jack are popularly sought as herbal medicinal supplements to improve libido and general health amongst the local ethnic population. The major Quassinoids of E. longifolia improved spermatogenesis and fertility but toxicity studies have not been well documented. The reproductive toxicity, two generation of foetus teratology and the up-and-down acute toxicity were investigated in Sprague–Dawley rats orally treated with Quassinoid-rich E. longifolia extract (TAF273). The results showed that the median lethal dose (LD50) of TAF273 for female and male rats was 1293 and >2000 mg/kg, respectively. Fertility index and litter size of the TAF273 treated were significantly increased when compared with those of the non-treated animals. The TAF273-treated dams decreased in percentage of pre-implantation loss, post-implantation loss and late resorption. No toxic symptoms were observed on the TAF273-treated pregnant female rats and their foetuses were normal. The no-observed adverse effect level (NOAEL) obtained from reproductive toxicity and teratology studies of TAF273 in rats was 100 mg/kg body weight/day, being more than 10-fold lower than the LD50 value. Thus, any human dose derived from converting the rat doses of 100 mg/kg and below may be considered as safe for further clinical studies. Copyright © 2013 John Wiley & Sons, Ltd.
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The Double-Peak Phenomenon and Bioavailability Studies of aQuassinoid-Rich Standardized Extract of Eurycoma Longifolia SolidDispersion Formulation
The Open Conference Proceedings Journal, 2013Co-Authors: Nurzalina Abdul Karim Khan, Kit-lam ChanAbstract:The Quassinoid-rich standardized extract of Eurycoma longifoia extract (TAF2) was found to possess various biological activities. However, the poor oral bioavailability of the bioactive Quassinoids, 13α(21)-epoxyeurycomanone (EP) and eurycomanone (EN) in TAF2 necessitated a new formulation design to be developed. A lipid-based solid dispersion was formulated and the bioavailabilities of EP and EN were significant improved compared with the conventional powder-filled capsules. A double peak phenomenon was identified in the plasma concentration-time curve. The gastric emptying and variability of GIT absorption, the probable causes of the double peak phenomenon, were studied by administering TAF2 solid dispersion to Sprague Dawley rats. As marker compounds, theophylline and sulfasalazine were used to determine the gastric emptying and variability of GIT absorption. The percentage absorbed of the markers was calculated using Wagner-Nelson method. The results showed that 50 % of theophylline was absorbed at 3 h, indicating the transit time of TAF2 solid dispersion from the stomach to the small intestine. Whereas, the 50 % of sulfapyridine, the metabolite of sulfasalazine, was absorbed at 8 h, reflected time of TAF2 solid dispersion to reach the colon. The concentration of TAF2 in colon was 74.36 % for EP and 80.27 % for EN, respectively. The results indicated that the delayed gastric emptying and colon absorption were the causes of double peak phenomenon. Thus, the delayed onset of in vivo activity of the Quassinoids in E. longifolia was probably due to the delay of gastric emptying and colon absorption.
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standardized Quassinoid rich eurycoma longifolia extract improved spermatogenesis and fertility in male rats via the hypothalamic pituitary gonadal axis
Journal of Ethnopharmacology, 2013Co-Authors: Binseng Low, Prashanta Kumar Das, Kit-lam ChanAbstract:Abstract Ethnopharmacological relevance Eurycoma longifolia Jack, a small Simaroubaceae tree, known locally as ‘Tongkat Ali’ is popularly used as a sexual tonic in traditional medicine for aphrodisiac activity and improvement of fertility and male libido. Aim of the study To investigate the effects of the standardized bioactive fraction of E. longifolia and its chemical constituents on the male fertility and the mechanisms of action involved. Material and methods The powdered roots of E. longifolia were extracted separately with methanol and water. The organic extract upon further fractionation on HP 20 resin and elution with the methanol/water mixture afforded four fractions (F1–F4). These fractions, together with the crude aqueous ( W ) and organic extracts were standardized following their respective major Quassinoid content and profile. The effects of the fractions on the rat spermatogenesis were compared with that of the aqueous extract ( W ) to determine the bioactive fraction. The effects of the bioactive fraction on the sperm count and quality, the histological morphometric changes on the spermatogenesis cycle, fertility and hormonal changes of plasma testosterone, luteinizing hormone (LH), follicle stimulating hormone (FSH) and estrogen in the animals upon oral administration were determined. The effects of the bioactive Quassinoids on the testosterone release from the isolated testicular interstitial cells rich in Leydig cells, were also described. Results The male rats orally administered with 25 mg/kg of F2 and 250 mg/kg of W , significantly increased the sperm concentration when compared with that of the control animals ( P P P p P P in vitro ( P Conclusion The standardised extract F2 of E. longifolia and its major Quassinoids especially eurycomanone improved the rat spermatogenesis by affecting the hypothalamic–pituitary–gonadal axis and the potential efficacy may be worthy of further investigation.
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Standardized Quassinoid-rich Eurycoma longifolia extract improved spermatogenesis and fertility in male rats via the hypothalamic–pituitary–gonadal axis
Journal of Ethnopharmacology, 2012Co-Authors: Kit-lam ChanAbstract:ETHNOPHARMACOLOGICAL RELEVANCE: Eurycoma longifolia Jack, a small Simaroubaceae tree, known locally as 'Tongkat Ali' is popularly used as a sexual tonic in traditional medicine for aphrodisiac activity and improvement of fertility and male libido. AIM OF THE STUDY: To investigate the effects of the standardized bioactive fraction of E. longifolia and its chemical constituents on the male fertility and the mechanisms of action involved. MATERIAL AND METHODS: The powdered roots of E. longifolia were extracted separately with methanol and water. The organic extract upon further fractionation on HP 20 resin and elution with the methanol/water mixture afforded four fractions (F1-F4). These fractions, together with the crude aqueous (W) and organic extracts were standardized following their respective major Quassinoid content and profile. The effects of the fractions on the rat spermatogenesis were compared with that of the aqueous extract (W) to determine the bioactive fraction. The effects of the bioactive fraction on the sperm count and quality, the histological morphometric changes on the spermatogenesis cycle, fertility and hormonal changes of plasma testosterone, luteinizing hormone (LH), follicle stimulating hormone (FSH) and estrogen in the animals upon oral administration were determined. The effects of the bioactive Quassinoids on the testosterone release from the isolated testicular interstitial cells rich in Leydig cells, were also described. RESULTS: The male rats orally administered with 25mg/kg of F2 and 250mg/kg of W, significantly increased the sperm concentration when compared with that of the control animals (P
Xin Fang - One of the best experts on this subject based on the ideXlab platform.
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Unprecedented Quassinoids with Promising Biological Activity from Harrisonia perforata
Angewandte Chemie (International ed. in English), 2015Co-Authors: Xin Fang, Yu Zhang, Qian Qian Chen, Qi Tai Zheng, Xiaojiang HaoAbstract:Perforalactone A (1), a new 20S Quassinoid with a unique cagelike 2,4-dioxaadamantane ring system and a migrated side chain, was isolated from the plant Harrisonia perforata together with two biosynthetically related new Quassinoids. The structures of these natural products were elucidated by NMR spectroscopy, X-ray diffraction analysis, computational modeling, and the CD excitation chirality method. The compounds exhibited notable biological properties, including insecticidal activity against Aphis medicaginis Koch and antagonist activity at the nicotinic acetylcholine receptor of Drosophila melanogaster. The structural features of these compounds may be related to their promising biological characteristics. Their biosynthesis and an alternative origin of Quassinoid-type natural products are also discussed.
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anti tobacco mosaic virus tmv Quassinoids from brucea javanica l merr
Journal of Agricultural and Food Chemistry, 2010Co-Authors: Xiaohui Yan, Jia Chen, Jiahong Dong, Peng Sang, Xin Fang, Zhongkai Zhang, Yuehu Wang, Xiaojiang HaoAbstract:Two new Quassinoids, javanicolide E (1) and javanicolide F (2), along with fifteen known C-20 Quassinoids were isolated from the seeds of Brucea javanica (L.) Merr. The antitobacco, mosaic virus (TMV) activity of these Quassinoids was screened by the conventional half-leaf and leaf-disk method along with Western blot analysis. All of the seventeen Quassinoids showed potent anti-TMV activity. Among them, eight compounds, brusatol (3), bruceine B (4), bruceoside B (5), yadanzioside 1 (6), yaclanzioside L (7), bruceine D (8), yadanziolide A (9), and aglycone of yadanziolide D (17), showed strong antiviral activities, with IC(50) values in the range of 3.42-5.66 mu M, and were much more effective than the positive control, ningnanmycin (IC(50) = 117.3 mu M). The antiviral structure-activity relationships of Quassinoids against TMV were also discussed.
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tobacco mosaic virus tmv inhibitors from picrasma quassioides benn
Journal of Agricultural and Food Chemistry, 2009Co-Authors: Jia Chen, Xiaohui Yan, Jiahong Dong, Peng Sang, Xin Fang, Zhongkai Zhang, Xiaojiang HaoAbstract:To investigate natural inhibitors against tobacco mosaic virus (TMV) from plants, 10 known β-carboline alkaloids and one Quassinoid have been isolated from MeOH extract of the wood of Picrasma quassioides Benn. These compounds were screened for their inhibitory activities against tobacco mosaic virus (TMV). The activity of each compound against TMV infection and replication was tested using a half-leaf assay method, a leaf-disk method, and Western blotting analyses. All of the β-carboline alkaloids showed moderate anti-TMV activities and exhibited synergistic effects when combined with the Quassinoid nigakilactone B (11). To our knowledge, this is the first report on anti-TMV activity of β-carbolines and their synergistic effects against TMV when combined with a Quassinoid.
Jia Chen - One of the best experts on this subject based on the ideXlab platform.
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anti tobacco mosaic virus tmv Quassinoids from brucea javanica l merr
Journal of Agricultural and Food Chemistry, 2010Co-Authors: Xiaohui Yan, Jia Chen, Jiahong Dong, Peng Sang, Xin Fang, Zhongkai Zhang, Yuehu Wang, Xiaojiang HaoAbstract:Two new Quassinoids, javanicolide E (1) and javanicolide F (2), along with fifteen known C-20 Quassinoids were isolated from the seeds of Brucea javanica (L.) Merr. The antitobacco, mosaic virus (TMV) activity of these Quassinoids was screened by the conventional half-leaf and leaf-disk method along with Western blot analysis. All of the seventeen Quassinoids showed potent anti-TMV activity. Among them, eight compounds, brusatol (3), bruceine B (4), bruceoside B (5), yadanzioside 1 (6), yaclanzioside L (7), bruceine D (8), yadanziolide A (9), and aglycone of yadanziolide D (17), showed strong antiviral activities, with IC(50) values in the range of 3.42-5.66 mu M, and were much more effective than the positive control, ningnanmycin (IC(50) = 117.3 mu M). The antiviral structure-activity relationships of Quassinoids against TMV were also discussed.
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tobacco mosaic virus tmv inhibitors from picrasma quassioides benn
Journal of Agricultural and Food Chemistry, 2009Co-Authors: Jia Chen, Xiaohui Yan, Jiahong Dong, Peng Sang, Xin Fang, Zhongkai Zhang, Xiaojiang HaoAbstract:To investigate natural inhibitors against tobacco mosaic virus (TMV) from plants, 10 known β-carboline alkaloids and one Quassinoid have been isolated from MeOH extract of the wood of Picrasma quassioides Benn. These compounds were screened for their inhibitory activities against tobacco mosaic virus (TMV). The activity of each compound against TMV infection and replication was tested using a half-leaf assay method, a leaf-disk method, and Western blotting analyses. All of the β-carboline alkaloids showed moderate anti-TMV activities and exhibited synergistic effects when combined with the Quassinoid nigakilactone B (11). To our knowledge, this is the first report on anti-TMV activity of β-carbolines and their synergistic effects against TMV when combined with a Quassinoid.
Xiaohui Yan - One of the best experts on this subject based on the ideXlab platform.
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anti tobacco mosaic virus tmv Quassinoids from brucea javanica l merr
Journal of Agricultural and Food Chemistry, 2010Co-Authors: Xiaohui Yan, Jia Chen, Jiahong Dong, Peng Sang, Xin Fang, Zhongkai Zhang, Yuehu Wang, Xiaojiang HaoAbstract:Two new Quassinoids, javanicolide E (1) and javanicolide F (2), along with fifteen known C-20 Quassinoids were isolated from the seeds of Brucea javanica (L.) Merr. The antitobacco, mosaic virus (TMV) activity of these Quassinoids was screened by the conventional half-leaf and leaf-disk method along with Western blot analysis. All of the seventeen Quassinoids showed potent anti-TMV activity. Among them, eight compounds, brusatol (3), bruceine B (4), bruceoside B (5), yadanzioside 1 (6), yaclanzioside L (7), bruceine D (8), yadanziolide A (9), and aglycone of yadanziolide D (17), showed strong antiviral activities, with IC(50) values in the range of 3.42-5.66 mu M, and were much more effective than the positive control, ningnanmycin (IC(50) = 117.3 mu M). The antiviral structure-activity relationships of Quassinoids against TMV were also discussed.
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tobacco mosaic virus tmv inhibitors from picrasma quassioides benn
Journal of Agricultural and Food Chemistry, 2009Co-Authors: Jia Chen, Xiaohui Yan, Jiahong Dong, Peng Sang, Xin Fang, Zhongkai Zhang, Xiaojiang HaoAbstract:To investigate natural inhibitors against tobacco mosaic virus (TMV) from plants, 10 known β-carboline alkaloids and one Quassinoid have been isolated from MeOH extract of the wood of Picrasma quassioides Benn. These compounds were screened for their inhibitory activities against tobacco mosaic virus (TMV). The activity of each compound against TMV infection and replication was tested using a half-leaf assay method, a leaf-disk method, and Western blotting analyses. All of the β-carboline alkaloids showed moderate anti-TMV activities and exhibited synergistic effects when combined with the Quassinoid nigakilactone B (11). To our knowledge, this is the first report on anti-TMV activity of β-carbolines and their synergistic effects against TMV when combined with a Quassinoid.
