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Eric Deharo - One of the best experts on this subject based on the ideXlab platform.
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Quassinoid constituents of quassia amara l simaroubaceae leaf herbal tea impact on its antimalarial activity and cytotoxicity
Planta Medica, 2010Co-Authors: Emeline Houel, Eric Deharo, Valerie Jullian, Genevieve Bourdy, Severine Chevalley, Alexis Valentin, Didier StienAbstract:French Guiana records high malaria incidence rates. The traditional antimalarial remedy most widespread and still very much in use there is a tea made out from Quassia amara mature leaves. The antimalarial activity of this preparation was assessed [1] and in order to optimize the in vitro activity, different types of preparation have been realized and tested. The most active in vitro preparation is an infusion of fresh young leaves. It demonstrated a very good activity, in vitro as well as in vivo [2]. A known Quassinoid, simalikalactone D (SkD), was identified as the active compound, with an IC50 value of 10 nM against FcB1 Plasmodium falciparum chloroquine resistant strain in vitro [3]. Our next objective was to assess whether it could be contemplated to recommend this young leaves tea for treatment against malaria, since it seemed from literature precedent that SkD was also cytotoxic to a number of cellular lineages [4,5]. We then characterized and quantified the antiparasitic and cytotoxic activities of all the constituents. Several Quassinoids were isolated and characterized in the tea: SkD, Quassin, neoQuassin, and picrasins B, H, I (new) and J (new), SkD being responsible of both antiplasmodial activity and cytotoxicity. In addition, in the context of an antimalarial treatment, it appeared that the dose necessary for obtaining a curative antimalarial effect is close to the toxic dose of an SkD analogue, bruceantin. Prior to emitting a definitive conclusion, a clinical study in humans similar to the one done with bruceantin [6] should be performed. References: 1. Bertani, S. et al. (2005)J. Ethnopharmacol. 98:45–54. 2. Bertani, S. et al. (2007)J. Ethnopharmacol.111:40–42. 3. Bertani, S. et al. (2006)J. Ethnopharmacol.108:155–157. 4. Ozeki, A. et al. (1998)J. Nat. Prod. 61:776–780. 5. Xu, Z. et al. (2000)J. Nat. Prod. 63:1712–1715. 6. Bedikian, A.Y. et al. (1979) Cancer Treat. Rep. 63:1843–1847.
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Quassinoid constituents of quassia amara l leaf herbal tea impact on its antimalarial activity and cytotoxicity
Journal of Ethnopharmacology, 2009Co-Authors: Emeline Houel, Eric Deharo, Stephane Bertani, Valerie Jullian, Genevieve Bourdy, Alexis ValentinAbstract:Abstract Aim of the study Our objective was to assess whether it could be contemplated to recommend Quassia amara young leaf tea for treatment against malaria, and if yes, set up a standard protocol for preparing the herbal tea. Materials and methods The leaf tea was extracted with methylene chloride and the organic extract was fractionated with HPLC. Pure compounds were characterized and their in vitro cytotoxicity and antiplasmodial activity was determined. Results and discussion We discovered that antimalarial Quassia amara young leaf tea contains several Quassinoids: simalikalactone D (SkD, 1 ), picrasin B ( 2 ), picrasin H ( 3 ), neoQuassin ( 4 ), Quassin ( 5 ), picrasin I ( 6 ) and picrasin J ( 7 ). These last two compounds are new. In addition, our experiments demonstrate that both biological activity and cytotoxicity of the remedy may be attributed solely to the presence of SkD. Conclusion In conclusion, this preparation should not be recommended for treatment of malaria until a clinical study in humans is performed with SkD.
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Evaluation of French Guiana traditional antimalarial remedies.
Journal of ethnopharmacology, 2005Co-Authors: Stephane Bertani, Genevieve Bourdy, J C Robinson, I Landau, Ph Esterre, Eric DeharoAbstract:In order to evaluate the antimalarial potential of traditional remedies used in French Guiana, 35 remedies were prepared in their traditional form and screened for blood schizonticidal activity in vitro on Plasmodium falciparum chloroquine re4sistant strain (W2). Some of these extracts were screened in vivo against Plasmodium yoelii rodent malaria. Ferriprotoporphyrin inhibition test was also performed. Four remedies, widely used among the population as preventives, were able to inhibit more than 50% of the parasite growth in vivo at around 100 mg/kg: Irlbachia alata (Gentiananceae), Picrolemma pseudocoffea (Simaroubaceae), Quassia amara (Simaroubaceae), Tinospora crispa (Menispermaceae) and Zanthoxylum rhoifolium (Rutaceae). Five remedies displayed an IC50 in vitro < 10 microg/ml: Picrolemma pseudocoffea, Pseudoxandra cuspidata (Annonaceae) and Quassia amara leaves and stem, together with a multi-ingredient recipe. Two remedies were more active than a Cinchona preparation on the ferriprotoporphyrin inhibition test: Picrolemma pseudocoffea and Quassia amara. We also showed that a traditional preventive remedy, made from Geissospermum argenteum bark macerated in rum, was able to impair the intrahepatic cycle of the parasite. For the first time, traditional remedies from French Guiana have been directly tested on malarial pharmacological assays and some have been shown to be active.
Alexis Valentin - One of the best experts on this subject based on the ideXlab platform.
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Quassinoid constituents of quassia amara l simaroubaceae leaf herbal tea impact on its antimalarial activity and cytotoxicity
Planta Medica, 2010Co-Authors: Emeline Houel, Eric Deharo, Valerie Jullian, Genevieve Bourdy, Severine Chevalley, Alexis Valentin, Didier StienAbstract:French Guiana records high malaria incidence rates. The traditional antimalarial remedy most widespread and still very much in use there is a tea made out from Quassia amara mature leaves. The antimalarial activity of this preparation was assessed [1] and in order to optimize the in vitro activity, different types of preparation have been realized and tested. The most active in vitro preparation is an infusion of fresh young leaves. It demonstrated a very good activity, in vitro as well as in vivo [2]. A known Quassinoid, simalikalactone D (SkD), was identified as the active compound, with an IC50 value of 10 nM against FcB1 Plasmodium falciparum chloroquine resistant strain in vitro [3]. Our next objective was to assess whether it could be contemplated to recommend this young leaves tea for treatment against malaria, since it seemed from literature precedent that SkD was also cytotoxic to a number of cellular lineages [4,5]. We then characterized and quantified the antiparasitic and cytotoxic activities of all the constituents. Several Quassinoids were isolated and characterized in the tea: SkD, Quassin, neoQuassin, and picrasins B, H, I (new) and J (new), SkD being responsible of both antiplasmodial activity and cytotoxicity. In addition, in the context of an antimalarial treatment, it appeared that the dose necessary for obtaining a curative antimalarial effect is close to the toxic dose of an SkD analogue, bruceantin. Prior to emitting a definitive conclusion, a clinical study in humans similar to the one done with bruceantin [6] should be performed. References: 1. Bertani, S. et al. (2005)J. Ethnopharmacol. 98:45–54. 2. Bertani, S. et al. (2007)J. Ethnopharmacol.111:40–42. 3. Bertani, S. et al. (2006)J. Ethnopharmacol.108:155–157. 4. Ozeki, A. et al. (1998)J. Nat. Prod. 61:776–780. 5. Xu, Z. et al. (2000)J. Nat. Prod. 63:1712–1715. 6. Bedikian, A.Y. et al. (1979) Cancer Treat. Rep. 63:1843–1847.
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Quassinoid constituents of quassia amara l leaf herbal tea impact on its antimalarial activity and cytotoxicity
Journal of Ethnopharmacology, 2009Co-Authors: Emeline Houel, Eric Deharo, Stephane Bertani, Valerie Jullian, Genevieve Bourdy, Alexis ValentinAbstract:Abstract Aim of the study Our objective was to assess whether it could be contemplated to recommend Quassia amara young leaf tea for treatment against malaria, and if yes, set up a standard protocol for preparing the herbal tea. Materials and methods The leaf tea was extracted with methylene chloride and the organic extract was fractionated with HPLC. Pure compounds were characterized and their in vitro cytotoxicity and antiplasmodial activity was determined. Results and discussion We discovered that antimalarial Quassia amara young leaf tea contains several Quassinoids: simalikalactone D (SkD, 1 ), picrasin B ( 2 ), picrasin H ( 3 ), neoQuassin ( 4 ), Quassin ( 5 ), picrasin I ( 6 ) and picrasin J ( 7 ). These last two compounds are new. In addition, our experiments demonstrate that both biological activity and cytotoxicity of the remedy may be attributed solely to the presence of SkD. Conclusion In conclusion, this preparation should not be recommended for treatment of malaria until a clinical study in humans is performed with SkD.
Qin Jiang - One of the best experts on this subject based on the ideXlab platform.
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Total synthesis of (+)-Quassin.
The Journal of organic chemistry, 2000Co-Authors: Tony Kung Ming Shing, Qin JiangAbstract:A total synthesis of (+)-Quassin from naturally occurring (S)-(+)-carvone is described. The total number of steps was 28, and the overall yield was about 2.6%. The synthetic strategy for the construction of the tetracyclic carbon framework was based on a C→ABC→ABCD ring annulation sequence, involving an aldol reaction, an intramolecular Diels−Alder reaction, and an intramolecular acylation as the key steps. Subsequent functionalization of ring A and ring C then afforded the target (+)-Quassin.
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total synthesis of Quassin
Journal of Organic Chemistry, 2000Co-Authors: Tony Kung Ming Shing, Qin JiangAbstract:A total synthesis of (+)-Quassin from naturally occurring (S)-(+)-carvone is described. The total number of steps was 28, and the overall yield was about 2.6%. The synthetic strategy for the construction of the tetracyclic carbon framework was based on a C→ABC→ABCD ring annulation sequence, involving an aldol reaction, an intramolecular Diels−Alder reaction, and an intramolecular acylation as the key steps. Subsequent functionalization of ring A and ring C then afforded the target (+)-Quassin.
Yinusa Raji - One of the best experts on this subject based on the ideXlab platform.
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cytotoxicity and acute oral toxicity study on Quassin and fractions of quassia amara extract
International Journal of Sciences: Basic and Applied Research, 2014Co-Authors: Olawale O Obembe, Ganiyat K. Oloyede, Yinusa RajiAbstract:Different fractions of Quassia amara and its bioactive compound Quassin have been implicated in male reproductive toxicology. Toxicity results obtained from brine shrimp lethality test on chloroform, methanol and hexane fractions of Quassia amara gave LC50 value of 93.4569μg/ml, 172.0463μg/ml, and 46.1941μg/ml respectively. LC50 of Quassin was 0.0000μg/ml. Acute oral toxicity was by OECD limit test procedure and methanol extract of Quassia amara showed no lethality up to 5000mg/kg. Quassia amara and Quassin therefore has toxicity activity. Methanol fraction is comparatively least toxic to brine shrimp and also well tolerated by the systemic organs of experimental rats.
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antiulcerogenic effects and possible mechanism of action of quassia amara l simaroubaceae extract and its bioactive principles in rats
African Journal of Traditional Complementary and Alternative Medicines, 2011Co-Authors: Yinusa Raji, Ganiyat K. OloyedeAbstract:The effects of Quassia amara extract (Q. amara) and its bioactive principles-Quassin and 2-methoxycanthin-6-one on gastric ulceration were studied in albino rats. Q. amara (200–800 mg/kg p.o.; 5–20 mg/kg i.p) and 2-methoxycanthin-6-one (12.5, 25.0 and 50.0 mg/kg p.o; 1, 2 and 4 mg/kg i.p) but not Quassin (12.5, 25.0 and 50 mg/kg p.o; 1, 2 and 4 mg/kg i.p) significantly inhibited gastric ulceration induced by indomethacin (40mg/kg). Administration of Q. amara (800 mg/kg p.o and 20 mg/kg i.p) and 2-methoxycanthin-6-one (12.5 mg/kg p.o; 4 mg/kg i.p) caused between 77%–85% cytoprotection against indomethacin (40 mg/kg, i.p) — induced gastric ulceration. Quassin did not cause any significant change in indomethacin-induced gastric ulceration. The inhibition of gastric ulceration produced by Q. amara and 2-methoxycanthin-6 one was accompanied by significant dose-dependent decreases (P< 0.01) in total gastric acidity. To investigate the probable mechanism of action, the individual effects of the extract and its principles alone and in combination with histamine (1 mg/kg) or cimetidine (0.12 mg/kg) on gastric acid secretion in situ were studied. Q. amara (20 mg/kg) and 2-methoxycanthin-6-one (4 mg/kg) but not Quassin significantly (P< 0.01) inhibited the basal and histamine-induced gastric acid secretion. Inhibition of gastric acid secretion by Q. amara and 2-methoxycanthin-6-one was accentuated by cimetidine. The results suggest that Q. amara and its bioactive principle, 2-methoxycanthin-6-one possess antiulcer activity probably acting via histamine H2 receptor. This could be a potential source of potent and effective antiulcer agents.
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effects of bioactive principles from stem bark extract of quassia amara Quassin and 2 methoxycanthine 6 one on haematological parameters in albino rats
Nigerian journal of physiological sciences : official publication of the Physiological Society of Nigeria, 2010Co-Authors: Yinusa RajiAbstract:Summary:The effect of Quassia amara extract and two isolated compounds from the extract, Quassin and 2-methoxycathine-6-one on haematological parameters was studied in rats. All doses of the extract and those of the Quassin significantly increased (p 0.05) in the total white blood cell count. There was also no significant change (P>0.05) in all parameters studied with 2-methoxycanthine-6-one. The results suggest that quassia extract possesses antianaemic property. Keywords : Anaemia, Quassinoid, Quassin, 2-methoxycanthine-6-one, Rats Nig. J. Physiol. Sci . 25(December 2010) 103 – 106
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Effects of bioactive principles from stem bark extract of Quassia amara , Quassin and 2-methoxycanthine-6-one, on haematological parameters in albino rats
Nigerian journal of physiological sciences : official publication of the Physiological Society of Nigeria, 2010Co-Authors: Yinusa RajiAbstract:The effect of Quassia amara extract and two isolated compounds from the extract, Quassin and 2-methoxycathine-6-one on haematological parameters was studied in rats. All doses of the extract and those of the Quassin significantly increased red blood cell count, packed cell volume and haemoglobin concentration.However, there was no significant increase in the total white blood cell count.There was also no significant change in all parameters studied with 2-methoxycanthine-6-one. The results suggest that quassia extract possesses antianaemic property.
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reproductive activities of female albino rats treated with Quassin a bioactive triterpenoid from stem bark extract of quassia amara
Nigerian journal of physiological sciences : official publication of the Physiological Society of Nigeria, 2010Co-Authors: Yinusa Raji, Adeniran Oluwadamilare Akinola, Ibukun P Oyeyipo, Omowunmi FemiakinlosotuAbstract:To evaluate the effect of Quassin on female reproductive functions, 42 albino rats (35 females and 7 males) were used. The female albino rats were divided into seven groups of five rats each. Group I served as the control group and received distilled water while Groups II, III and IV rats were treatedorally with 0.1mg/kg, 1.0 mg/kg and 2.0 mg/kg body weight of Quassin for 60 days respectively. Groups V, VI and VII rats were also treated orally with 0.1 mg/kg, 1.0mg/kg and 2.0 mg/kg body weight of Quassin for 60 days but were left untreated for another 30 days, to serve as the recovery groups. At the end of each experimental period, blood samples were collected from each rat. Fertility study was done by cohabiting one untreated male with the five female rats in each group for 10 days. Quassin did not adversely affect the weight of the kidney, heart, liver and the body of the rats. However there was a significant decrease(P < 0.05) in the weight of the ovary and uterus in all the groups relative to the control. There was also a significant decrease (P <0.05) in serum estrogen levels in Quassin treated rats. The Quassin treated rats had a significantly decreased (P < 0.05) mean litter number and weight. Histological studies show a disorganization and degeneration in the ovary while the uterus showed signs of vacuolation and disorganization. However, these effects were ameliorated after Quassin was withdrawn from the rats. The results suggest that Quassin has female anti-fertility properties, possibly acting via inhibition of estrogen secretion. Keywords: Quassin, Female rat, Reproduction, Estrogen Nig. J. Physiol. Sci . 25(December 2010) 95 – 102
Genevieve Bourdy - One of the best experts on this subject based on the ideXlab platform.
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Quassinoid constituents of quassia amara l simaroubaceae leaf herbal tea impact on its antimalarial activity and cytotoxicity
Planta Medica, 2010Co-Authors: Emeline Houel, Eric Deharo, Valerie Jullian, Genevieve Bourdy, Severine Chevalley, Alexis Valentin, Didier StienAbstract:French Guiana records high malaria incidence rates. The traditional antimalarial remedy most widespread and still very much in use there is a tea made out from Quassia amara mature leaves. The antimalarial activity of this preparation was assessed [1] and in order to optimize the in vitro activity, different types of preparation have been realized and tested. The most active in vitro preparation is an infusion of fresh young leaves. It demonstrated a very good activity, in vitro as well as in vivo [2]. A known Quassinoid, simalikalactone D (SkD), was identified as the active compound, with an IC50 value of 10 nM against FcB1 Plasmodium falciparum chloroquine resistant strain in vitro [3]. Our next objective was to assess whether it could be contemplated to recommend this young leaves tea for treatment against malaria, since it seemed from literature precedent that SkD was also cytotoxic to a number of cellular lineages [4,5]. We then characterized and quantified the antiparasitic and cytotoxic activities of all the constituents. Several Quassinoids were isolated and characterized in the tea: SkD, Quassin, neoQuassin, and picrasins B, H, I (new) and J (new), SkD being responsible of both antiplasmodial activity and cytotoxicity. In addition, in the context of an antimalarial treatment, it appeared that the dose necessary for obtaining a curative antimalarial effect is close to the toxic dose of an SkD analogue, bruceantin. Prior to emitting a definitive conclusion, a clinical study in humans similar to the one done with bruceantin [6] should be performed. References: 1. Bertani, S. et al. (2005)J. Ethnopharmacol. 98:45–54. 2. Bertani, S. et al. (2007)J. Ethnopharmacol.111:40–42. 3. Bertani, S. et al. (2006)J. Ethnopharmacol.108:155–157. 4. Ozeki, A. et al. (1998)J. Nat. Prod. 61:776–780. 5. Xu, Z. et al. (2000)J. Nat. Prod. 63:1712–1715. 6. Bedikian, A.Y. et al. (1979) Cancer Treat. Rep. 63:1843–1847.
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Quassinoid constituents of quassia amara l leaf herbal tea impact on its antimalarial activity and cytotoxicity
Journal of Ethnopharmacology, 2009Co-Authors: Emeline Houel, Eric Deharo, Stephane Bertani, Valerie Jullian, Genevieve Bourdy, Alexis ValentinAbstract:Abstract Aim of the study Our objective was to assess whether it could be contemplated to recommend Quassia amara young leaf tea for treatment against malaria, and if yes, set up a standard protocol for preparing the herbal tea. Materials and methods The leaf tea was extracted with methylene chloride and the organic extract was fractionated with HPLC. Pure compounds were characterized and their in vitro cytotoxicity and antiplasmodial activity was determined. Results and discussion We discovered that antimalarial Quassia amara young leaf tea contains several Quassinoids: simalikalactone D (SkD, 1 ), picrasin B ( 2 ), picrasin H ( 3 ), neoQuassin ( 4 ), Quassin ( 5 ), picrasin I ( 6 ) and picrasin J ( 7 ). These last two compounds are new. In addition, our experiments demonstrate that both biological activity and cytotoxicity of the remedy may be attributed solely to the presence of SkD. Conclusion In conclusion, this preparation should not be recommended for treatment of malaria until a clinical study in humans is performed with SkD.
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Evaluation of French Guiana traditional antimalarial remedies.
Journal of ethnopharmacology, 2005Co-Authors: Stephane Bertani, Genevieve Bourdy, J C Robinson, I Landau, Ph Esterre, Eric DeharoAbstract:In order to evaluate the antimalarial potential of traditional remedies used in French Guiana, 35 remedies were prepared in their traditional form and screened for blood schizonticidal activity in vitro on Plasmodium falciparum chloroquine re4sistant strain (W2). Some of these extracts were screened in vivo against Plasmodium yoelii rodent malaria. Ferriprotoporphyrin inhibition test was also performed. Four remedies, widely used among the population as preventives, were able to inhibit more than 50% of the parasite growth in vivo at around 100 mg/kg: Irlbachia alata (Gentiananceae), Picrolemma pseudocoffea (Simaroubaceae), Quassia amara (Simaroubaceae), Tinospora crispa (Menispermaceae) and Zanthoxylum rhoifolium (Rutaceae). Five remedies displayed an IC50 in vitro < 10 microg/ml: Picrolemma pseudocoffea, Pseudoxandra cuspidata (Annonaceae) and Quassia amara leaves and stem, together with a multi-ingredient recipe. Two remedies were more active than a Cinchona preparation on the ferriprotoporphyrin inhibition test: Picrolemma pseudocoffea and Quassia amara. We also showed that a traditional preventive remedy, made from Geissospermum argenteum bark macerated in rum, was able to impair the intrahepatic cycle of the parasite. For the first time, traditional remedies from French Guiana have been directly tested on malarial pharmacological assays and some have been shown to be active.
