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Xianming Chen - One of the best experts on this subject based on the ideXlab platform.
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first report of oregon grape Mahonia aquifolium as an alternate host for the wheat stripe rust pathogen puccinia striiformis f sp tritici under artificial inoculation
Plant Disease, 2013Co-Authors: Meinan Wang, Xianming ChenAbstract:As the primary host of the stripe rust pathogen, Puccinia striiformis f. sp. tritici (Pst), wheat can be infected by both aeciospores and urediniospores, and later is the host that gives rise to urediniospores and teliospores. Barberry species (e.g., Berberis vulgaris) can be infected by basidiospores, produced from the teliospores of wheat plants, and later gives rise to pycniospores and aeciospores, which has been demonstrated through artificial inoculation (3). Oregon grape (Mahonia aquifolium), closely related to Berberis, is a native evergreen shrub that is also grown as an ornamental plant in the Pacific Northwest. To determine if M. aquifolium can also serve as an alternate host for Pst, we conducted artificial inoculations under controlled conditions. Seeds of M. aquifolium collected from Pullman, WA, were sown in pots filled with soil mixture, and plants were grown in a greenhouse under wheat-growing conditions (1). In the first experiment, conducted in May to June 2011, the inoculum was telia co...
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First Report of Oregon Grape (Mahonia aquifolium) as an Alternate Host for the Wheat Stripe Rust Pathogen (Puccinia striiformis f. sp. tritici) Under Artificial Inoculation
Plant disease, 2013Co-Authors: Meinan Wang, Xianming ChenAbstract:As the primary host of the stripe rust pathogen, Puccinia striiformis f. sp. tritici (Pst), wheat can be infected by both aeciospores and urediniospores, and later is the host that gives rise to urediniospores and teliospores. Barberry species (e.g., Berberis vulgaris) can be infected by basidiospores, produced from the teliospores of wheat plants, and later gives rise to pycniospores and aeciospores, which has been demonstrated through artificial inoculation (3). Oregon grape (Mahonia aquifolium), closely related to Berberis, is a native evergreen shrub that is also grown as an ornamental plant in the Pacific Northwest. To determine if M. aquifolium can also serve as an alternate host for Pst, we conducted artificial inoculations under controlled conditions. Seeds of M. aquifolium collected from Pullman, WA, were sown in pots filled with soil mixture, and plants were grown in a greenhouse under wheat-growing conditions (1). In the first experiment, conducted in May to June 2011, the inoculum was telia collected from artificially inoculated wheat cv. Avocet S with urediniospores of isolate 09-134 (race PST-127) from the greenhouse. In the second experiment, conducted in July to August 2011, the inoculum was telia collected from naturally infected wheat cv. Nugaines with urediniospores from isolate 11-292 (race PST-127) from an experimental field near Pullman. For each experiment, mature teliospores of 60 telia from a single wheat plant were suspended in 1.0 ml of distilled water and inoculated with a fine paint brush onto the leaves of seven or eight 10- to 15-day-old plants of M. aquifolium. Plants were incubated initially in a dew chamber at 10°C for 72 h in darkness, then transferred to a growth chamber with a diurnal temperature cycle of 10 to 24°C and a 16 h light/8 h dark cycle (1). Reddish pycnia with nectar appeared on adaxial surfaces of inoculated leaves at 12 days post-inoculation (DPI), and reddish aecia were produced on the baxial surface at 16 DPI. All 15 M. aquifolium leaves of the 15 plants inoculated with teliospores produced pycnia and aecia. Seedlings of Nugaines and Avocet S, wheat cultivars that are susceptible to all Pst races (1), were then inoculated with a water suspension of aeciospores of 30 aecia collected from the M. aquifolium plants. Wheat plants were incubated as described above for M. aquifolium. Uredinia appeared at 15 DPI, and telia were produced after an additional 15 days. From these uredinia that formed on inoculated wheat, a total of 30 single-uredinium isolates were obtained using the standard procedure (1). Virulence tests were carried out on 20 wheat differentials for 10 randomly selected urediniospore isolates, revealing six virulence patterns. When tested with four selected Pst SSR markers (PstP001, PstP003, PstP005, PstP029) (2) and compared to other race PST-127 isolates, all 10 progeny isolates were homozygous, as were the parental isolates (09-134, 11-292). The virulence tests and marker genotypes verified that the urediniospore isolates resulted from infection by aecia, produced by parental isolate 09-134 through its sexual cycle on M. aquifolium. The study exhibited the completed sexual lifecycle of Pst through the five spore stages on wheat and M. aquifolium in a controlled setting, and suggests that under appropriate weather conditions, M. aquifolium may serve as an alternate host for Pst. Due to the wide distribution of M. aquifolium, further studies are needed to determine if the species can be infected by Pst under natural conditions. References: (1) X. M. Chen et al. Can. J. Plant Pathol. 32:315, 2010. (2) P. Cheng et al. Mol. Ecol. Resour. 12:779, 2012. (3) Y. Jin et al. Phytopathology 100:432, 2010.
Meinan Wang - One of the best experts on this subject based on the ideXlab platform.
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first report of oregon grape Mahonia aquifolium as an alternate host for the wheat stripe rust pathogen puccinia striiformis f sp tritici under artificial inoculation
Plant Disease, 2013Co-Authors: Meinan Wang, Xianming ChenAbstract:As the primary host of the stripe rust pathogen, Puccinia striiformis f. sp. tritici (Pst), wheat can be infected by both aeciospores and urediniospores, and later is the host that gives rise to urediniospores and teliospores. Barberry species (e.g., Berberis vulgaris) can be infected by basidiospores, produced from the teliospores of wheat plants, and later gives rise to pycniospores and aeciospores, which has been demonstrated through artificial inoculation (3). Oregon grape (Mahonia aquifolium), closely related to Berberis, is a native evergreen shrub that is also grown as an ornamental plant in the Pacific Northwest. To determine if M. aquifolium can also serve as an alternate host for Pst, we conducted artificial inoculations under controlled conditions. Seeds of M. aquifolium collected from Pullman, WA, were sown in pots filled with soil mixture, and plants were grown in a greenhouse under wheat-growing conditions (1). In the first experiment, conducted in May to June 2011, the inoculum was telia co...
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First Report of Oregon Grape (Mahonia aquifolium) as an Alternate Host for the Wheat Stripe Rust Pathogen (Puccinia striiformis f. sp. tritici) Under Artificial Inoculation
Plant disease, 2013Co-Authors: Meinan Wang, Xianming ChenAbstract:As the primary host of the stripe rust pathogen, Puccinia striiformis f. sp. tritici (Pst), wheat can be infected by both aeciospores and urediniospores, and later is the host that gives rise to urediniospores and teliospores. Barberry species (e.g., Berberis vulgaris) can be infected by basidiospores, produced from the teliospores of wheat plants, and later gives rise to pycniospores and aeciospores, which has been demonstrated through artificial inoculation (3). Oregon grape (Mahonia aquifolium), closely related to Berberis, is a native evergreen shrub that is also grown as an ornamental plant in the Pacific Northwest. To determine if M. aquifolium can also serve as an alternate host for Pst, we conducted artificial inoculations under controlled conditions. Seeds of M. aquifolium collected from Pullman, WA, were sown in pots filled with soil mixture, and plants were grown in a greenhouse under wheat-growing conditions (1). In the first experiment, conducted in May to June 2011, the inoculum was telia collected from artificially inoculated wheat cv. Avocet S with urediniospores of isolate 09-134 (race PST-127) from the greenhouse. In the second experiment, conducted in July to August 2011, the inoculum was telia collected from naturally infected wheat cv. Nugaines with urediniospores from isolate 11-292 (race PST-127) from an experimental field near Pullman. For each experiment, mature teliospores of 60 telia from a single wheat plant were suspended in 1.0 ml of distilled water and inoculated with a fine paint brush onto the leaves of seven or eight 10- to 15-day-old plants of M. aquifolium. Plants were incubated initially in a dew chamber at 10°C for 72 h in darkness, then transferred to a growth chamber with a diurnal temperature cycle of 10 to 24°C and a 16 h light/8 h dark cycle (1). Reddish pycnia with nectar appeared on adaxial surfaces of inoculated leaves at 12 days post-inoculation (DPI), and reddish aecia were produced on the baxial surface at 16 DPI. All 15 M. aquifolium leaves of the 15 plants inoculated with teliospores produced pycnia and aecia. Seedlings of Nugaines and Avocet S, wheat cultivars that are susceptible to all Pst races (1), were then inoculated with a water suspension of aeciospores of 30 aecia collected from the M. aquifolium plants. Wheat plants were incubated as described above for M. aquifolium. Uredinia appeared at 15 DPI, and telia were produced after an additional 15 days. From these uredinia that formed on inoculated wheat, a total of 30 single-uredinium isolates were obtained using the standard procedure (1). Virulence tests were carried out on 20 wheat differentials for 10 randomly selected urediniospore isolates, revealing six virulence patterns. When tested with four selected Pst SSR markers (PstP001, PstP003, PstP005, PstP029) (2) and compared to other race PST-127 isolates, all 10 progeny isolates were homozygous, as were the parental isolates (09-134, 11-292). The virulence tests and marker genotypes verified that the urediniospore isolates resulted from infection by aecia, produced by parental isolate 09-134 through its sexual cycle on M. aquifolium. The study exhibited the completed sexual lifecycle of Pst through the five spore stages on wheat and M. aquifolium in a controlled setting, and suggests that under appropriate weather conditions, M. aquifolium may serve as an alternate host for Pst. Due to the wide distribution of M. aquifolium, further studies are needed to determine if the species can be infected by Pst under natural conditions. References: (1) X. M. Chen et al. Can. J. Plant Pathol. 32:315, 2010. (2) P. Cheng et al. Mol. Ecol. Resour. 12:779, 2012. (3) Y. Jin et al. Phytopathology 100:432, 2010.
Viktor Kettmann - One of the best experts on this subject based on the ideXlab platform.
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Free radical scavenging activity and lipoxygenase inhibition of Mahonia aquifolium extract and isoquinoline alkaloids.
Journal of inflammation (London England), 2007Co-Authors: Lucia Račková, Viktor Kettmann, Marek Oblozinsky, Daniela Košt’álová, Lydia BezakovaAbstract:Roots and stem-bark of Mahonia aquifolium (Oregon grape) (Berberidaceae) are effectively used in the treatment of skin inflammatory conditions.
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Free radical scavenging activity and lipoxygenase inhibition of Mahonia aquifolium extract and isoquinoline alkaloids.
Journal of inflammation (London England), 2007Co-Authors: Lucia Račková, Viktor Kettmann, Marek Oblozinsky, Daniela Košt’álová, Lydia BezakovaAbstract:Roots and stem-bark of Mahonia aquifolium (Oregon grape) (Berberidaceae) are effectively used in the treatment of skin inflammatory conditions.In the present study, the effect of Mahonia aquifolium crude extract and its two representative alkaloid fractions containing protoberberine and bisbenzylisoquinoline (BBIQ) alkaloids on activity of 12-lipoxygenase (12-LOX), was studied. The reactivity with 1,1-diphenyl-2-picryl-hydrazyl (DPPH), a free stable radical, was evaluated to elucidate the rate of possible lipid-derived radical scavenging in the mechanism of the enzyme inhibition.The results indicate that although the direct radical scavenging mechanism cannot be ruled out in the lipoxygenase inhibition by Mahonia aquifolium and its constituents, other mechanisms based on specific interaction between enzyme and alkaloids could play the critical role in the lipoxygenase inhibition rather than non-specific reactivity with free radicals.
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Journal of Inflammation BioMed Central
2007Co-Authors: Lucia Račková, Viktor Kettmann, Marek Oblozinsky, Lydia Bezakova, Daniela Kostalova, Open AccessAbstract:Free radical scavenging activity and lipoxygenase inhibition of Mahonia aquifolium extract and isoquinoline alkaloid
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Antimicrobial activity of Mahonia aquifolium crude extract and its major isolated alkaloids.
Phytotherapy research : PTR, 2004Co-Authors: Lívia Slobodníková, Daniela Košt’álová, Darina Labudová, Daniela Kotulová, Viktor KettmannAbstract:The crude extract of Mahonia aquifolium (Pursh) Nutt. stem bark and its two main protoberberine alkaloids, berberine and jatrorrhizine, were tested for their in vitro antimicrobial activity. Twenty strains of coagulase-negative staphylococci and 20 strains of Propionibacterium acnes isolated from skin lesions of patients with a severe form of acne, and 20 strains of Candida sp. isolated from chronic vulvovaginal candidoses were tested for their susceptibility to crude extract and two isolated alkaloids. The minimum inhibitory concentrations obtained in this study illustrate the varying degrees of antibacterial and antifungal activity of the tested agents. The results indicate a rational basis for the traditional use of Mahonia aquifolium for localized skin and mucosal infection therapy, as well as for the possible development of a preparation for supportive therapy of the diseases mentioned above.
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Antifungal activity of Mahonia aquifolium extract and its major protoberberine alkaloids.
Phytotherapy research : PTR, 2003Co-Authors: Anna Volleková, Viktor Kettmann, Daniela Košt’álová, Jaroslav TóthAbstract:The crude extract of Mahonia aquifolium (Berberidaceae) stem bark and its components berberine, palmatine and jatrorrhizine were screened for their inhibitory activity against a variety of dermatophytes and two Candida species of human origin using the in vitro dilution agar plate method. Jatrorrhizine was found to be the most effective against all fungal species tested (MIC ranges from 62.5 to 125 µg/mL), while the crude extract, berberine, and palmatine exhibited only marginal activity (MIC 500 to ≥ 1000 µg/mL). Dermatophytes were more susceptible to jatrorrhizine than yeasts, and Scopulariopsis brevicaulis appeared the least sensitive species to all the compounds tested. The effects of the alkaloids were compared with those of .uconazole and bifonazole for which the MIC ranges were 12.5 to >100 µg/mL. Our results suggest that jatrorrhizine may serve as a leading compound for further studies to develop new antifungal agents with highly potent antifungal activity and low host toxicity. Copyright © 2003 John Wiley & Sons, Ltd.
Lydia Bezakova - One of the best experts on this subject based on the ideXlab platform.
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Free radical scavenging activity and lipoxygenase inhibition of Mahonia aquifolium extract and isoquinoline alkaloids.
Journal of inflammation (London England), 2007Co-Authors: Lucia Račková, Viktor Kettmann, Marek Oblozinsky, Daniela Košt’álová, Lydia BezakovaAbstract:Roots and stem-bark of Mahonia aquifolium (Oregon grape) (Berberidaceae) are effectively used in the treatment of skin inflammatory conditions.
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Free radical scavenging activity and lipoxygenase inhibition of Mahonia aquifolium extract and isoquinoline alkaloids.
Journal of inflammation (London England), 2007Co-Authors: Lucia Račková, Viktor Kettmann, Marek Oblozinsky, Daniela Košt’álová, Lydia BezakovaAbstract:Roots and stem-bark of Mahonia aquifolium (Oregon grape) (Berberidaceae) are effectively used in the treatment of skin inflammatory conditions.In the present study, the effect of Mahonia aquifolium crude extract and its two representative alkaloid fractions containing protoberberine and bisbenzylisoquinoline (BBIQ) alkaloids on activity of 12-lipoxygenase (12-LOX), was studied. The reactivity with 1,1-diphenyl-2-picryl-hydrazyl (DPPH), a free stable radical, was evaluated to elucidate the rate of possible lipid-derived radical scavenging in the mechanism of the enzyme inhibition.The results indicate that although the direct radical scavenging mechanism cannot be ruled out in the lipoxygenase inhibition by Mahonia aquifolium and its constituents, other mechanisms based on specific interaction between enzyme and alkaloids could play the critical role in the lipoxygenase inhibition rather than non-specific reactivity with free radicals.
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Journal of Inflammation BioMed Central
2007Co-Authors: Lucia Račková, Viktor Kettmann, Marek Oblozinsky, Lydia Bezakova, Daniela Kostalova, Open AccessAbstract:Free radical scavenging activity and lipoxygenase inhibition of Mahonia aquifolium extract and isoquinoline alkaloid
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Lipoxygenase inhibition and antioxidant properties of bisbenzylisoqunoline alkaloids isolated from Mahonia aquifolium.
Die Pharmazie, 1996Co-Authors: Lydia Bezakova, V. Misik, L. Malekova, Emil Švajdlenka, D. KostálováAbstract:Products of lipoxygenase metabolism are known to play a role in the pathogenesis of psoriasis. Six bisbenzylisoquinoline (BBIQ) alkaloids, oxyacanthine, armoline, baluchistine, berbamine, obamegine, aquifoline, isolated from Mahonia aquifolium, were tested for lipoxygenase inhibition. Berbamine and oxyacanthine were the most potent lipoxygenase inhibitors, whereas aromoline and baluchistine exhibited only very low potencies. Oxyacanthine and berbamine were also among the most active compounds to inhibit lipid peroxidation. Between the results of lipoxygenase inhibition and the lipid peroxidation a linear correlation was found (r = 0.9533). Our data suggest that in the mechanism of lipoxygenase inhibition by these alkaloids, inhibition of lipid peroxide substrate accumulation, either by direct reaction with peroxide or by scavenging or lipid-derived radicals, may play a role. Inhibition of lipoxygenase by these compounds may contribute to the therapeutic effect of Mahonia aquifolium extracts in treatment of diseases in pathogenesis of which he products of lipoxygenase metabolism are involved.
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Lipoxygenase inhibition and antioxidant properties of protoberberine and aporphine alkaloids isolated from Mahonia aquifolium.
Planta medica, 1995Co-Authors: V. Misik, Lydia Bezakova, Ľubica Máleková, Daniela KošťálováAbstract:Products of lipoxygenase metabolism play a role in the pathogenesis of psoriasis. Four protoberberine alkaloids, berberine, oxyberberine, jatrorrhizine, columbamine, and two aporphine alkaloids, magnoflorine, and corytuberine, isolated from Mahonia aquifolium, were tested for lipoxygenase inhibition. Oxyberberine, corytuberine, and columbamine were the most potent lipoxygenase inhibitors tested, whereas berberine and magnoflorine exhibited only low potencies. A strong linear correlation (r = 0.866) between lipoxygenase inhibition and lipid antioxidant properties of these compounds was found. These data suggest that the mechanism of lipoxygenase inhibition by these alkaloids may be linked to the inhibition of lipid hydroperoxide substrate accumulation. Inhibition of lipoxygenase by these compounds may contribute to the therapeutic effect of M. aquifolium extracts in the treatment of psoriasis.
Daniela Košt’álová - One of the best experts on this subject based on the ideXlab platform.
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Free radical scavenging activity and lipoxygenase inhibition of Mahonia aquifolium extract and isoquinoline alkaloids.
Journal of inflammation (London England), 2007Co-Authors: Lucia Račková, Viktor Kettmann, Marek Oblozinsky, Daniela Košt’álová, Lydia BezakovaAbstract:Roots and stem-bark of Mahonia aquifolium (Oregon grape) (Berberidaceae) are effectively used in the treatment of skin inflammatory conditions.
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Free radical scavenging activity and lipoxygenase inhibition of Mahonia aquifolium extract and isoquinoline alkaloids.
Journal of inflammation (London England), 2007Co-Authors: Lucia Račková, Viktor Kettmann, Marek Oblozinsky, Daniela Košt’álová, Lydia BezakovaAbstract:Roots and stem-bark of Mahonia aquifolium (Oregon grape) (Berberidaceae) are effectively used in the treatment of skin inflammatory conditions.In the present study, the effect of Mahonia aquifolium crude extract and its two representative alkaloid fractions containing protoberberine and bisbenzylisoquinoline (BBIQ) alkaloids on activity of 12-lipoxygenase (12-LOX), was studied. The reactivity with 1,1-diphenyl-2-picryl-hydrazyl (DPPH), a free stable radical, was evaluated to elucidate the rate of possible lipid-derived radical scavenging in the mechanism of the enzyme inhibition.The results indicate that although the direct radical scavenging mechanism cannot be ruled out in the lipoxygenase inhibition by Mahonia aquifolium and its constituents, other mechanisms based on specific interaction between enzyme and alkaloids could play the critical role in the lipoxygenase inhibition rather than non-specific reactivity with free radicals.
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Antimicrobial activity of Mahonia aquifolium crude extract and its major isolated alkaloids.
Phytotherapy research : PTR, 2004Co-Authors: Lívia Slobodníková, Daniela Košt’álová, Darina Labudová, Daniela Kotulová, Viktor KettmannAbstract:The crude extract of Mahonia aquifolium (Pursh) Nutt. stem bark and its two main protoberberine alkaloids, berberine and jatrorrhizine, were tested for their in vitro antimicrobial activity. Twenty strains of coagulase-negative staphylococci and 20 strains of Propionibacterium acnes isolated from skin lesions of patients with a severe form of acne, and 20 strains of Candida sp. isolated from chronic vulvovaginal candidoses were tested for their susceptibility to crude extract and two isolated alkaloids. The minimum inhibitory concentrations obtained in this study illustrate the varying degrees of antibacterial and antifungal activity of the tested agents. The results indicate a rational basis for the traditional use of Mahonia aquifolium for localized skin and mucosal infection therapy, as well as for the possible development of a preparation for supportive therapy of the diseases mentioned above.
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Oxygen activation by photoexcited protoberberinium alkaloids from Mahonia aquifolium.
Phytotherapy research : PTR, 2004Co-Authors: Vlasta Brezová, Dana Dvoranová, Daniela Košt’álováAbstract:Protoberberinium salts, i.e. berberine (I), palmatine (II) and jatrorrhizine (III) prepared from Mahonia aquifolium (Pursh) Nutt. belong to isoquinoline alkaloids possessing interesting biological activity (e.g. antibacterial, antimalarial, antitumor). The characteristic UV/Vis absorption band maxima of I-III iodide salts were found in regions 350 and 425 nm in dimethylsulfoxide (DMSO) and ethanol solvents, and were only negligibly influenced by substitution changes on the C-2 and C-3 positions. The fluorescence intensity of protoberberinium salts monitored in ethanol solutions was significantly lowered by iodide counter-ions, and decreased in the order berberine > palmatine > jatrorrhizine. EPR spectroscopy supplied evidence of the formation of super-oxide anion radicals and singlet oxygen upon irradiation of berberine in oxygenated DMSO solvent. The photochemical generation of O(2) (.-) and (1)O(2) in DMSO solutions of palmatine and jatrorrhizine was substantially lower, and probably reflected the replacement of a photolabile methylenedioxy group at C-2 and C-3 positions in the berberine molecule by two methoxy groups in palmatine, and methoxyl (C-2) and hydroxyl (C-3) substitution in jatrorrhizine. Additionally, the powder EPR spectra of protoberberinium iodides I-III measured at 290 K revealed the presence of single-line EPR signals (g(eff) = 2.0044), which were attributed to hydroperoxidic structures produced by the autoxidation process. The photochemical reactions of protoberbenium salts producing reactive oxygen species after UVA excitation should be integrated in biological activity investigations, as well as in their applications in skin disorder treatment.
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Antiradical and antioxidant activities of alkaloids isolated from Mahonia aquifolium. Structural aspects.
Bioorganic & medicinal chemistry, 2004Co-Authors: Lucia Račková, Daniela Košt’álová, Magdalena Majekova, Milan StefekAbstract:The antioxidant activities of three alkaloids isolated from Mahonia aquifolium--berberine, jatrorrhizine, and magnoflorine--were studied with respect to their structural aspects, particularly the presence and the position of -OH groups, steric conditions of unpaired electron delocalization and parameters of lipophilicity and hydration energy. The antiradical activities of the compounds tested were evaluated as the reactivities toward free stable alpha,alpha'-diphenyl-beta-picrylhydrazyl radical (DPPH). The antioxidant features of the alkaloids tested were investigated in heterogeneous membrane system of DOPC liposomes stressed by peroxidative damage induced by AAPH azoinitiator. Both alkaloids bearing free phenolic groups--jatrorrhizine and magnoflorine--showed better activities in both systems used than berberine not bearing any readily abstractable hydrogen on its skeleton. The former two showed antiperoxidative efficiency in DOPC liposomal membrane comparable to that of an effective scavenger of peroxyl radicals--stobadine-and higher than that of Trolox. We conclude that the favorable antioxidant features of the hydroxylated alkaloids are most probably ensured by the combination of reasonably high antiradical reactivity with high lipophilicity, however, the solvation process was found to markedly interfere with these beneficial effects.