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Keriman Gunaydin - One of the best experts on this subject based on the ideXlab platform.
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Khellin a furanochromone with toxicity against oncopeltus fasciatus hemiptera and aedes aegypti diptera
Journal of Natural Pharmaceuticals, 2013Co-Authors: Marise Maleck, Keriman Gunaydin, Fernanda Cristina Carvalho Dos Santos, Michele Teixeira Serdeiro, Anthony Erico Guimaraes, Bruna Ferreira, Ana Paula De Almeida, Ceceten Vassouras Rj BrasilAbstract:Natural products isolated from plants may be an alternative source of larvicidal and insecticide activity. Khellin is a natural furanochromone isolated from fruits of Ammi visnaga (L.) Lam. (Umbelliferae family), which grows extensively in the Mediterranean region. This substance shows several types of biological activity, such as in vitro cytotoxicity, antispasmodic action, and phototherapeutic potential. Dengue is a tropical disease caused by an arbovirus transmitted by Aedes aegypti; the milkweed bug, Oncopeltus fasciatus, is a phytophagous Hemiptera and a Phytomonas vector. Our main goal was to evaluate the toxicity of Khellin in relation to the nymphs of O. fasciatus (Hemiptera) and larvae of A. aegypti (Diptera). To the best of our knowledge, this is the fi rst report concerning furanochromone bioactivity against insect vectors for human disease.
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the chemical investigations on the ripe fruits of ammi visnaga lam lamarck growing in turkey
Natural Product Research, 2004Co-Authors: Keriman Gunaydin, Neslihan BeyazitAbstract:Two furanochromones and one furanochromone glycoside were isolated from the fruits of Ammi visnaga (L.) Lam. They were identified as Khellin, visnagin, and khellol glycoside by interpretation of spectral analyses. Quantitative determination of furanochromones in A. visnaga (L.) ripe fruits from Hatay region (Turkey) was carried out by ultraviolet spectrophotometry and gas chromatography. In addition, photochemical properties of furanochromones and chemical composition of essential oil were determined.
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determination of Khellin and visnagin in ammi visnaga fruits by capillary electrophoresis
Journal of Chromatography A, 2002Co-Authors: Keriman Gunaydin, F B ErimAbstract:Abstract A new, simple and rapid capillary electrophoresis method was developed for the identification and quantitative determination of two medically active constituents—Khellin and visnagin—in the extracts of Ammi visnaga fruits. Micellar electrochromatographic separation of Khellin and visnagin was carried out using 10 mmol/l borate, 50 mmol/l sodium dodecylsulfate, 25% (v/v) acetonitrile at pH 9 as running buffer. Ammi visnaga fruits were extracted with methanol and the extracts were directly injected without any purification and pre-separation processes. Coumarin was used as internal standard for quantitation and the limits of detection for Khellin and visnagin were 2.36 and 1.97 μg/ml, respectively using UV detection at 245 nm.
Stephen O. Duke - One of the best experts on this subject based on the ideXlab platform.
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Khellin and visnagin furanochromones from ammi visnaga l lam as potential bioherbicides
Journal of Agricultural and Food Chemistry, 2016Co-Authors: Maria L. Travaini, Gustavo M. Sosa, Eduardo A. Ceccarelli, Helmut Walter, Charles L. Cantrell, Franck E. Dayan, Kumudini M. Meepagala, Nestor Carrillo, Stephen O. DukeAbstract:Plants constitute a source of novel phytotoxic compounds to be explored in searching for effective and environmentally safe herbicides. From a previous screening of plant extracts for their phytotoxicity, a dichloromethane extract of Ammi visnaga (L.) Lam. was selected for further study. Phytotoxicity-guided fractionation of this extract yielded two furanochromones, Khellin and visnagin, for which herbicidal activity had not been described before. Khellin and visnagin were phytotoxic to model species lettuce (Lactuca sativa) and duckweed (Lemna paucicostata), with IC50 values ranging from 110 to 175 μM. These compounds also inhibited the growth and germination of a diverse group of weeds at 0.5 and 1 mM. These weeds included five grasses [ryegrass (Lolium multiflorum), barnyardgrass (Echinocloa crus-galli), crabgrass (Digitaria sanguinalis), foxtail (Setaria italica), and millet (Panicum sp.)] and two broadleaf species [morningglory (Ipomea sp.) and velvetleaf (Abutilon theophrasti)]. During greenhouse st...
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Khellin and Visnagin, Furanochromones from Ammi visnaga (L.) Lam., as Potential Bioherbicides
2016Co-Authors: Maria L. Travaini, Gustavo M. Sosa, Eduardo A. Ceccarelli, Helmut Walter, Charles L. Cantrell, Nestor J. Carrillo, Franck E. Dayan, Kumudini M. Meepagala, Stephen O. DukeAbstract:Plants constitute a source of novel phytotoxic compounds to be explored in searching for effective and environmentally safe herbicides. From a previous screening of plant extracts for their phytotoxicity, a dichloromethane extract of Ammi visnaga (L.) Lam. was selected for further study. Phytotoxicity-guided fractionation of this extract yielded two furanochromones, Khellin and visnagin, for which herbicidal activity had not been described before. Khellin and visnagin were phytotoxic to model species lettuce (Lactuca sativa) and duckweed (Lemna paucicostata), with IC50 values ranging from 110 to 175 μM. These compounds also inhibited the growth and germination of a diverse group of weeds at 0.5 and 1 mM. These weeds included five grasses [ryegrass (Lolium multiflorum), barnyardgrass (Echinocloa crus-galli), crabgrass (Digitaria sanguinalis), foxtail (Setaria italica), and millet (Panicum sp.)] and two broadleaf species [morningglory (Ipomea sp.) and velvetleaf (Abutilon theophrasti)]. During greenhouse studies visnagin was the most active and showed significant contact postemergence herbicidal activity on velvetleaf and crabgrass at 2 kg active ingredient (ai) ha–1. Moreover, its effect at 4 kg ai ha–1 was comparable to the bioherbicide pelargonic acid at the same rate. The mode of action of Khellin and visnagin was not a light-dependent process. Both compounds caused membrane destabilization, photosynthetic efficiency reduction, inhibition of cell division, and cell death. These results support the potential of visnagin and, possibly, Khellin as bioherbicides or lead molecules for the development of new herbicides
F B Erim - One of the best experts on this subject based on the ideXlab platform.
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determination of Khellin and visnagin in ammi visnaga fruits by capillary electrophoresis
Journal of Chromatography A, 2002Co-Authors: Keriman Gunaydin, F B ErimAbstract:Abstract A new, simple and rapid capillary electrophoresis method was developed for the identification and quantitative determination of two medically active constituents—Khellin and visnagin—in the extracts of Ammi visnaga fruits. Micellar electrochromatographic separation of Khellin and visnagin was carried out using 10 mmol/l borate, 50 mmol/l sodium dodecylsulfate, 25% (v/v) acetonitrile at pH 9 as running buffer. Ammi visnaga fruits were extracted with methanol and the extracts were directly injected without any purification and pre-separation processes. Coumarin was used as internal standard for quantitation and the limits of detection for Khellin and visnagin were 2.36 and 1.97 μg/ml, respectively using UV detection at 245 nm.
Neslihan Beyazit - One of the best experts on this subject based on the ideXlab platform.
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crystal structure and dna binding properties of Khellin oxime
Journal of Molecular Structure, 2019Co-Authors: Neslihan Beyazit, Kerem Kaya, Pelin şenel, Ayse Daut Ozdemir, Aysegul GolcuAbstract:Abstract The dried fruits of Ammi visnaga were subjected to Soxhlet extraction with water, followed by hexane and purified by column chromatography to yield Khellin ( 1) . Oximation of 1 yielded Khellin oxime ( 2), crystallized by slow evaporation from CH 2 Cl 2 :EtOAc (6:3), characterized by single-crystal X-ray diffraction method for the first time. The DNA binding affinities of the 1 and 2 have been appraised by examining their ability to bind to dsFSDNA with ultraviolet-visible and fluorescence spectroscopies, thermal denaturation and square wave voltammetry techniques. The binding constants of the both compounds with dsFSDNA are calculated by UV-vis measurements. The square wave voltammograms proved that both compounds bind to dsFSDNA by intercalative binding mode. Competitive studies with ethidium bromide (EB) have shown that 1 and 2 exhibit the ability to displace the DNA-bound EB indicating 1 and 2 bind to DNA with intercalation with EB for the intercalative binding site as a challenging displacement.
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the chemical investigations on the ripe fruits of ammi visnaga lam lamarck growing in turkey
Natural Product Research, 2004Co-Authors: Keriman Gunaydin, Neslihan BeyazitAbstract:Two furanochromones and one furanochromone glycoside were isolated from the fruits of Ammi visnaga (L.) Lam. They were identified as Khellin, visnagin, and khellol glycoside by interpretation of spectral analyses. Quantitative determination of furanochromones in A. visnaga (L.) ripe fruits from Hatay region (Turkey) was carried out by ultraviolet spectrophotometry and gas chromatography. In addition, photochemical properties of furanochromones and chemical composition of essential oil were determined.
Paola Martelli - One of the best experts on this subject based on the ideXlab platform.
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pertussis toxin reverses the inhibition of the adenylyl cyclase system by Khellin in hela cells
Biochimica et Biophysica Acta, 1996Co-Authors: Anna Di Stefano, Lucia Bovalini, Rita La Gaetana, Paola Lusini, Paola MartelliAbstract:Abstract Khellin, a furochromone structurally related to furocoumarins, is a phototherapeutic agent used against psoriasis and vitiligo. This paper reports that pretreatment of HeLa cells with pertussis toxin reverses both the inhibition of NaF-stimulated adenylyl cyclase activity and the stimulation of GTPase by Khellin alone and plus UVA light, as previously reported. Our results demonstrate, for the first time, the Khellin is able to elicit an intracellular response by Giα protein.
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Khellin but not 8 methoxypsoralen inhibits adenylyl cyclase system in hela cells
Biochimica et Biophysica Acta, 1995Co-Authors: Anna Di Stefano, Rita La Gaetana, Paola Lusini, Lorenza Trabalzini, Luca Parente, Paola MartelliAbstract:Abstract Until recently, the therapeutic effects of furocoumarins and furochromones plus UV-A light were thought to be due to their ability to form photoadducts with DNA in the cell nuclei; now it appears that membrane effector systems may be involved as targets. Here we show that in HeLa cells Khellin at 1 and 5 μM final concentration, in combination with UV-A light, inhibits NaF-stimulated adenylyl cyclase activity and Pertussis Toxin (PT)-catalyzed ADP-ribosylation of α-subunits of inhibitory guanine nucleotide regulatory proteins (Gi) and increases GTPase activity. In the same experimental conditions, 8-methoxypsoralen (8-MOP), either alone or plus UV-A, does not affect adenylyl cyclase and GTPase activities. Our results suggest that in HeLa cells, through an interaction with a receptor and the mediation of Gi proteins, the adenylyl cyclase system is a target for Khellin but not for 8-MOP.
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investigation of the mutagenic activity in salmonella typhimurium of the furochromone Khellin proposed as a therapeutic agent for skin diseases
Mutation Research\ genetic Toxicology, 1992Co-Authors: Maria Letizia Riccio, Grazietta Coratza, Lucia Bovalini, Paola MartelliAbstract:Abstract The photomutagenicity of the furochromone Khellin was tested in Ames Salmonella strains using 8-methoxypsoralen (8-MOP) and 4,5',8-trimethylpsoralen (TMP) as positive controls. When Khellin was assayed with strain TA1537, mutation induction was not detectable; in the same strain, an equitoxic dose (52–56% level of survival) of TMP (used at a concentration 12-fold lower than Khellin and with a UVA dose 83-fold lower than that used with Khellin; yielded an increase in revertants/plate 3-fold above the spontaneous background. In strain TA102, Khellin plus UVA treatment yielded a 2-fold increase in revertants/plate above the spontaneous background (79% survival). 8-MOP, however, used at a concentration 8-fold lower than Khellin with a UVA dose 13-fold lower than Khellin, yielded an increase in revertants/plate about 14-fold above background (66% survival) in the same strain. These data show that Khellin has a weak photomutagenic potential and, along with the previously reported low photogenotoxic potential in eukaryotic cell systems, support the notion that Khellin may be safer than bifunctional psoralens for clinical use.
