The Experts below are selected from a list of 1491 Experts worldwide ranked by ideXlab platform
Kenichi Miyauchi - One of the best experts on this subject based on the ideXlab platform.
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antibacterial activity of Xanthones from guttiferaeous plants against methicillin resistant staphylococcus aureus
Journal of Pharmacy and Pharmacology, 1996Co-Authors: Munekazu Iinuma, Fujio Asai, Ryoyu Shimano, Yasuko Kobayashi, Hideki Tosa, Toshiyuki Tanaka, Kenichi MiyauchiAbstract:Extracts of Garcinia mangostana (Guttiferae) showing inhibitory effects against the growth of S. aureus NIHJ 209p were fractionated according to guidance obtained from bioassay and some of the components with activity against methicillin-resistant Staphylococcus aureus (MRSA) were characterized. One active isolate, α-mangostin, a Xanthone Derivative, had a minimum inhibitory concentration (MIC) of 1.57-12.5 μg mL -1 . Other related Xanthones were also examined to determine their anti-MRSA activity. RubraXanthone, which was isolated from Garcinia dioica and has a structure similar to that of α-mangostin, had the highest activity against staphylococcal strains (MIC = 0.31-1.25 μg mL -1 ), an activity which was greater than that of the antibiotic vancomycin (3.13-6.25 μg mL -1 ). The inhibitory effect against strains of MRSA of two of the compounds when used in conjunction with other antibiotics was also studied. The anti-MRSA activity of α-mangostin was clearly increased by the presence of vancomycin ; this behaviour was not observed for rubraXanthone. The strong in-vitro antibacterial activity of Xanthone Derivatives against both methicillin-resistant and methicillin-sensitive Staphylococcus aureus suggests the compounds might find wide pharmaceutical use.
Munekazu Iinuma - One of the best experts on this subject based on the ideXlab platform.
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inhibitory effects of crude alpha mangostin a Xanthone Derivative on two different categories of colon preneoplastic lesions induced by 1 2 dimethylhydrazine in the rat
Asian Pacific Journal of Cancer Prevention, 2004Co-Authors: Viengvansay Nabandith, Munekazu Iinuma, Yukihiro Akao, Masumi Suzui, Takamitsu Morioka, Tatsuya Kaneshiro, Tatsuya Kinjo, Kenji Matsumoto, Naoki YoshimiAbstract:The purpose of this study was to examine whether crude alpha-mangostin (a major Xanthone Derivative in mangosteen pericarp (Garcinia mangostana)) has short-term chemopreventive effects on putative preneoplastic lesions involved in rat colon carcinogenesis. The crude preparation was obtained by simple recrystallization of an ethylacetate extract of mangosteen pericarps. A total of 33 five-week-old male F344 rats were randomly divided into 5 experimental groups. Rats in groups 1-3 were given a subcutaneous injection of 1,2-dimethylhydrazine (DMH)(40 mg/kg body weight) once a week for 2 weeks. Starting one week before the first injection of DMH, rats in groups 2 and 3 were fed a diet containing 0.02% and 0.05% crude alpha-mangostin, respectively, for 5 weeks. Rats in group 4 also received the diet containing 0.05% crude alpha-mangostin, while rats in group 5 served as untreated controls. The experiment was terminated 5 weeks after the start. Dietary administration of crude alpha-mangostin at both doses significantly inhibited the induction and/or development of aberrant crypt foci (ACF) (P<0.05 for 0.02% crude alpha-mangostin, P<0.01 for 0.05% crude alpha-mangostin), when compared to the DMH-treated group (group 1). Moreover, treatment of rats with 0.05% crude alpha-mangostin significantly decreased dysplastic foci (DF) (P<0.05) and beta-catenin accumulated crypts (BCAC) (P<0.05), to below the group 1 values. The proliferating cell nuclear antigen (PCNA) labeling indices of colon epithelium and focal lesions in groups 2 and 3 were also significantly lower than in group 1 and this effect occurred in a dose dependent manner of the crude alpha-mangostin. This finding that crude alpha-mangostin has potent chemopreventive effects in our short-term colon carcinogenesis bioassay system suggests that longer exposure might result in suppression of tumor development.
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INHIBITORY ACTIVITY OF Xanthone DerivativeS ISOLATED FROM SOME GUTTIFERAEOUS PLANTS AGAINST DNA TOPOSIOMERASES I AND II
CHEMICAL & PHARMACEUTICAL BULLETIN, 1997Co-Authors: Hideki Tosa, Munekazu Iinuma, Toshiyuki Tanaka, Hiroshi Nozaki, Shougo Ikeda, Ken Tsutsui, Kimiko Tsutusi, Masashi Yamada, Shiho FujimoriAbstract:A Xanthone Derivative, subelliptenone F, and the related compounds showed an intensive inhibitory effect against topoisomerases I and II in in vitro experiments. These Xanthones are prospective lead compounds for anticancer drugs.
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antibacterial activity of Xanthones from guttiferaeous plants against methicillin resistant staphylococcus aureus
Journal of Pharmacy and Pharmacology, 1996Co-Authors: Munekazu Iinuma, Fujio Asai, Ryoyu Shimano, Yasuko Kobayashi, Hideki Tosa, Toshiyuki Tanaka, Kenichi MiyauchiAbstract:Extracts of Garcinia mangostana (Guttiferae) showing inhibitory effects against the growth of S. aureus NIHJ 209p were fractionated according to guidance obtained from bioassay and some of the components with activity against methicillin-resistant Staphylococcus aureus (MRSA) were characterized. One active isolate, α-mangostin, a Xanthone Derivative, had a minimum inhibitory concentration (MIC) of 1.57-12.5 μg mL -1 . Other related Xanthones were also examined to determine their anti-MRSA activity. RubraXanthone, which was isolated from Garcinia dioica and has a structure similar to that of α-mangostin, had the highest activity against staphylococcal strains (MIC = 0.31-1.25 μg mL -1 ), an activity which was greater than that of the antibiotic vancomycin (3.13-6.25 μg mL -1 ). The inhibitory effect against strains of MRSA of two of the compounds when used in conjunction with other antibiotics was also studied. The anti-MRSA activity of α-mangostin was clearly increased by the presence of vancomycin ; this behaviour was not observed for rubraXanthone. The strong in-vitro antibacterial activity of Xanthone Derivatives against both methicillin-resistant and methicillin-sensitive Staphylococcus aureus suggests the compounds might find wide pharmaceutical use.
Augustin E Nkengfack - One of the best experts on this subject based on the ideXlab platform.
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antiproliferative activity of a new Xanthone Derivative from leaves of garcinia nobilis engl
Natural Product Research, 2020Co-Authors: Hugues Fouotsa, Augustin E Nkengfack, Celine Djama Mbazoa, Alain Meli Lannang, Jean Paul Dzoyem, Hansgeorg Stammler, Michel Luhmer, Eric Allemann, Florence Delie, Franck MeyerAbstract:A new Xanthone, mboudieXanthone (1), together with five known compounds, euXanthone (2), isogarcinol (3), garcinol (4), betulinic acid (5) and zeorin (6) were isolated from the leaves of Garcinia n...
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a new Xanthone Derivative from twigs of garcinia nobilis
Natural Product Research, 2014Co-Authors: Hugues Fouotsa, Augustin E Nkengfack, Simplice J N Tatsimo, Beate Neumann, Carmela Michalek, Celine Djama Mbazoa, Norbert Sewald, Alain Meli LannangAbstract:Phytochemical investigation of the twigs of Garcinia nobilis led to the isolation of a new Xanthone, named l-hydroxy-2,5-dimethoxyXanthone (1), together with 15 known compounds (2-16). The structures of the new and known compounds were established by means of spectroscopic methods and by comparison with previously reported data. The structure of compound 1 was confirmed by X-ray diffraction data. Compounds 1-16 were tested for their cytotoxic activity against human cervix carcinoma cell line KB-3-1. Compounds 5 and 11 showed moderate activity while others showed weak biological activity in these cytotoxicity assays. Compounds 4 and 9 were found to be inactive.
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Antimicrobial and antileishmanial Xanthones from the stem bark of Allanblackia gabonensis
Chemistry of Natural Compounds, 2008Co-Authors: Anatole Guy Blaise Azebaze, Augustin E Nkengfack, B. M. W. Ouahouo, J. C. Vardamides, A. Valentin, V. Kuete, L. Acebey, V. P. Beng, M. MeyerAbstract:The phytochemical study of the stem bark of Allanblackia gabonensis has resulted in the isolation and characterization of one new Xanthone Derivative, named allanXanthone D, together with ten known compounds, including six Xanthone Derivatives, allanXanthone A, 1,5-dihydroxyXanthone, 1,7-dihydroxyXanthone and 1,3,6,7-tetrahydroxy-2-(3-methylbut-2-enyl)Xanthone, forbeXanthone, 6-deoxyisojacareubin, one polyisoprenylated benzophenone, guttiferone F, one flavanol, epicathechin, two phytosterols, β -sitosterol, and campesterol. The structures of these compounds were established on the basis of one- and two-dimensional NMR homo- and heteronuclear evidence. These compounds were evaluated for their activity against Leishmania amazonensis in vitro and antimicrobial activities against a range of Gram -negative and Gram- positive bacteria.
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antimicrobial and cytotoxic agents from calophyllum inophyllum
Phytochemistry, 2004Co-Authors: Marie C Yimdjo, Anatole Guy Blaise Azebaze, Augustin E Nkengfack, Michele A Meyer, Bernard Bodo, Zacharias Tanee FomumAbstract:The study of the chemical constituents of the root bark and the nut of Calophyllum inophyllum has resulted in the isolation and characterization of a Xanthone Derivative, named inoXanthone, 3, together with 12 known compounds: caloXanthones A, 4 and B, 5, macluraXanthone, 6, 1,5-dihydroxyXanthone, 7, calophynic acid, 8, brasiliensic acid, 9 inophylloidic acid, 10, friedelan-3-one, 11, calaustralin, 12, calophyllolide, 13, inophyllums C, 14 and E, 15. Their structures were established on the basis of spectral evidence. Their in vitro cytotoxicity against the KB cell line and their antibacterial activity and potency against a wide range of micro organisms were evaluated.
Louis Maes - One of the best experts on this subject based on the ideXlab platform.
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phytochemical antimicrobial and antiprotozoal evaluation of garcinia mangostana pericarp and α mangostin its major Xanthone Derivative
Molecules, 2013Co-Authors: Shaza M Almassarani, Ali El A Gamal, Nawal M Almusayeib, Ramzi A Mothana, Omer A Basudan, Adnan J Alrehaily, Mohamed A Farag, Mahmoud H Assaf, Kamaleldin El H Tahir, Louis MaesAbstract:Five Xanthone Derivatives and one flavanol were isolated from the dichloromethane extract of Garcinia mangostana. Dichloromethane, ethyl acetate extract and the major Xanthone (α-mangostin) were evaluated in vitro against erythrocytic schizonts of Plasmodium falciparum, intracellular amastigotes of Leishmania infantum and Trypanosoma cruzi and free trypomastigotes of T. brucei. The major constituent α-mangostin was also checked for antimicrobial potential against Candida albicans, Escherichia coli, Pseudomonas aeruginosa, Bacillius subtilis, Staphylococcus aureus, Mycobacterium smegmatis, M. cheleneoi, M. xenopi and M. intracellulare. Activity against
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Phytochemical, antimicrobial and antiprotozoal evaluation of Garcinia mangostana pericarp and α-mangostin, its major Xanthone Derivative.
Molecules (Basel Switzerland), 2013Co-Authors: Shaza M. Al-massarani, Ramzi A Mothana, Omer A Basudan, Mohamed A Farag, Mahmoud H Assaf, Ali A. El Gamal, Nawal M. Al-musayeib, Adnan J. Al-rehaily, Kamaleldin H. El Tahir, Louis MaesAbstract:Five Xanthone Derivatives and one flavanol were isolated from the dichloromethane extract of Garcinia mangostana. Dichloromethane, ethyl acetate extract and the major Xanthone (α-mangostin) were evaluated in vitro against erythrocytic schizonts of Plasmodium falciparum, intracellular amastigotes of Leishmania infantum and Trypanosoma cruzi and free trypomastigotes of T. brucei. The major constituent α-mangostin was also checked for antimicrobial potential against Candida albicans, Escherichia coli, Pseudomonas aeruginosa, Bacillius subtilis, Staphylococcus aureus, Mycobacterium smegmatis, M. cheleneoi, M. xenopi and M. intracellulare. Activity against P. falciparum (IC50 2.7 μg/mL) and T. brucei (IC50 0.5 μg/mL) were observed for the dichloromethane extract, however, with only moderate selectivity was seen based on a parallel cytotoxicity evaluation on MRC-5 cells (IC50 9.4 μg/mL). The ethyl acetate extract was inactive (IC50 > 30 µg/mL). The major constituent α-mangostin showed rather high cytotoxicity (IC50 7.5 µM) and a broad but non-selective antiprotozoal and antimicrobial activity profile. This in vitro study endorses that the antiprotozoal and antimicrobial potential of prenylated Xanthones is non-conclusive in view of the low level of selectivity.
Alain Meli Lannang - One of the best experts on this subject based on the ideXlab platform.
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antiproliferative activity of a new Xanthone Derivative from leaves of garcinia nobilis engl
Natural Product Research, 2020Co-Authors: Hugues Fouotsa, Augustin E Nkengfack, Celine Djama Mbazoa, Alain Meli Lannang, Jean Paul Dzoyem, Hansgeorg Stammler, Michel Luhmer, Eric Allemann, Florence Delie, Franck MeyerAbstract:A new Xanthone, mboudieXanthone (1), together with five known compounds, euXanthone (2), isogarcinol (3), garcinol (4), betulinic acid (5) and zeorin (6) were isolated from the leaves of Garcinia n...
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a new Xanthone Derivative from twigs of garcinia nobilis
Natural Product Research, 2014Co-Authors: Hugues Fouotsa, Augustin E Nkengfack, Simplice J N Tatsimo, Beate Neumann, Carmela Michalek, Celine Djama Mbazoa, Norbert Sewald, Alain Meli LannangAbstract:Phytochemical investigation of the twigs of Garcinia nobilis led to the isolation of a new Xanthone, named l-hydroxy-2,5-dimethoxyXanthone (1), together with 15 known compounds (2-16). The structures of the new and known compounds were established by means of spectroscopic methods and by comparison with previously reported data. The structure of compound 1 was confirmed by X-ray diffraction data. Compounds 1-16 were tested for their cytotoxic activity against human cervix carcinoma cell line KB-3-1. Compounds 5 and 11 showed moderate activity while others showed weak biological activity in these cytotoxicity assays. Compounds 4 and 9 were found to be inactive.
