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Andrew R Gillespie - One of the best experts on this subject based on the ideXlab platform.
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Occurrence and fate of the phytotoxin Juglone in alley soils under black walnut trees.
Journal of environmental quality, 2007Co-Authors: Guntram R. Von Kiparski, Linda S. Lee, Andrew R GillespieAbstract:Juglone (5-hydroxy-1,4-napthoquinone) is a chemical released by walnut trees, which can be toxic at various levels to several plant species. A balance among competing source and sink mechanisms and rates will ultimately determine whether Juglone is capable of attaining sufficient levels to be allelopathic to intercrops in a walnut tree agroforestry system. In this study, Juglone's release, accumulation, and decline in soil are explored using data from soil beneath a black walnut tree (Juglans nigra L) alley cropping system, greenhouse pot studies, and laboratory sorption/degradation studies. Juglone pore water concentrations estimated from extracts of surficial soil from beneath the alley cropping system exceeded the lowest solution culture toxicity levels reported for some plants of 10 -7 M, but did not exceed the inhibition threshold reported for typical intercrops such as maize and soybeans 10 -5 M. Further assessment of the likely persistence of Juglone in soils indicated that Juglone is both microbially and abiotically degraded, and that it will be particularly short-lived in soils supporting microbial activity. However, walnut seedlings planted in sand-filled pots clearly showed that Juglone is released in measurable quantities to the soil's rhizosphere. Therefore, Juglone accumulation in low fertility soils is plausible, and may still be worthy of consideration in management of alley agroforestry systems.
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allelopathy in black walnut juglans nigra l alley cropping i spatio temporal variation in soil Juglone in a black walnut corn zea mays l alley cropping system in the midwestern usa
Plant and Soil, 1998Co-Authors: Shibu Jose, Andrew R GillespieAbstract:A study was conducted to quantify the spatial and temporal variation in soil Juglone (5-hydroxy-1,4-naphthoquinone) in a 10-year-old black walnut (Juglans nigra L.)–corn (Zea mays L.) alley cropping system. Two treatments (‘root barrier’ and ‘no barrier’) were applied to determine if soil Juglone in the alley can be minimized by preventing black walnut root growth into the alley. Although no significant seasonal variation in soil Juglone existed, a distinct spatial pattern was observed. Juglone concentration decreased as much as 80% as the distance increased to 4.25 m from the tree row. Installation of polyethylene root barriers minimized Juglone concentration to trace levels in the alley. However, this treatment increased Juglone levels within the tree row as compared to the ‘no barrier’ treatment, probably as a result of increased rooting density within a limited volume of soil.
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allelopathy in black walnut juglans nigra l alley cropping ii effects of Juglone on hydroponically grown corn zea mays l and soybean glycine max l merr growth and physiology
Plant and Soil, 1998Co-Authors: Shibu Jose, Andrew R GillespieAbstract:We conducted an experiment to investigate the effects of Juglone (5-hydroxy-1, 4-napthoquinone) on the growth and physiology of hydroponically grown corn (Zea mays L.) and soybean (Glycine max L. Merr.) seedlings. Three different concentrations of Juglone (10-6 M, 10-5 M, and 10-4 M) along with a control were applied. Within 3 days, Juglone exhibited significant inhibitory effects on all measured variables including shoot and root relative growth rates (RGRs and RGRr), leaf photosynthesis (Pnet), transpiration (E), stomatal conductance (gs), and leaf and root respiration. In general, soybean was found to be more sensitive to Juglone than corn. RGRr was the most inhibited variable for both species, and reductions of 86.5 and 99% were observed in corn and soybean, respectively, with 10-4 M Juglone concentrations. Among the physiological variables measured, Pnet showed the greatest impact of toxicity though the other physiological parameters were also impacted. We conclude that both corn and soybean are sensitive to Juglone and observed growth reductions in corn and soybean in black walnut alley cropping may partly be due to Juglone phytotoxicity. Determination of actual phytotoxicity will require quantification of soil solution Juglone levels, particularly in areas where soil solid-phase levels are high in close proximity to trees.
İsmail Kocaçalişkan - One of the best experts on this subject based on the ideXlab platform.
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Cytotoxic and mutagenic potential of Juglone: a comparison of free and nano-encapsulated form.
Arhiv za higijenu rada i toksikologiju, 2020Co-Authors: Semiha Erişen, İsmail Kocaçalişkan, Tulin Arasoglu, Banu Mansuroglu, Serap DermanAbstract:Despite its evidenced beneficial herbicidal, antibacterial, antiviral, antifungal, and antioxidant effects, the application of Juglone (5-hydroxy-1,4,-naphthoquinone) is limited due to its low water solubility and allelopathic and toxic effects. In recent years, research has aimed to overcome these limitations by increasing its solubility and controlling its release through nanoparticular systems. This is the first study to have synthesised and characterised Juglone-loaded polymeric nanoparticles and compared them with free Juglone for cytotoxicity in mouse (L929 fibroblasts) and alfalfa cells and for mutagenic potential in Salmonella typhimurium TA98/100. Mouse and plant cells treated with free and nano-encapsulated Juglone showed a decrease in cell viability in a dose and time-dependent manner, but this effect was significantly lower with the nano-encapsulated form at lower doses. In the TA98 strain with S9, nano-encapsulated Juglone did not exhibit mutagenic effects, unlike the free form. Since all results show that Juglone encapsulation with polymeric nanoparticles reduced the toxic and mutagenic effects, it has a promising potential to be applied in medicine, food safety, and agriculture.
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Effect of Juglone on Seed Germination and Seedling Growth of Four Common Vegetables
International Journal of Life Sciences and Biotechnology, 2019Co-Authors: İsmail Kocaçalişkan, Tuğçe Akgül, Semiha ErişenAbstract:In this study, effect of Juglone on seed germination and post-germinative seedling growth of four common vegetables (aubergine, pepper, zucchini and gherkin) has been investigated. Juglone treatments were applied at 0 (control), 0.001, 0.01, 0.1 and 1 mM concentrations. Seed germination of aubergine and pepper was significantly inhibited by Juglone but in the case of zucchini and gherkin, Juglone didn’t change the germination of the seeds. However, both root and shoot elongation and dry weights of the seedlings of all the species studied were significantly decreased by Juglone above 0.01 mM concentrations with respect to control. The sensitivity range of the species to Juglone was determined as aubergine, pepper, zucchini and gherkin. That is, the most sensitive species to Juglone was found aubergine that Juglone inhibited its seedling growth at even 0.001 mM concentration.
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Synthesis, characterization and antibacterial activity of Juglone encapsulated PLGA nanoparticles.
Journal of applied microbiology, 2017Co-Authors: Tulin Arasoglu, Busra Gumus, Tayfun Acar, Serap Derman, Banu Mansuroglu, Gozde Yelkenci, Busra Kocyigit, İsmail KocaçalişkanAbstract:AIMS The aim of the study was to examine the effect of different process parameters which including; initial Juglone amount, initial poly(d,l-lactide co-glycolide) amount, polyvinyl alcohol volume and polyvinyl alcohol concentration on encapsulation of Juglone to poly(d,l-lactide co-glycolide) nanoparticles. METHODS AND RESULTS The synthesized nanoparticle formulations were analyzed for reaction yield, encapsulation efficiency, particle size, polydispersity, zeta potential and Juglone release. In conjunction with the highest encapsulation rate, the highest amount of Juglone release was obtained for F4 formulation, which has 281·8 nm particle size, 0·217 polydispersity index, and -19·55 mV zeta potential. After the detailed physicochemical characterization of this formulation, the four different kinetic models were used and it was found that Juglone release mechanism controlled by Fickian diffusion method. According to antimicrobial activity results, minimal inhibitory concentration (MIC) values of both F4 and free Juglone is higher for Gram negative bacteria than Gram positive bacteria. Inhibition zone diameters in the quantitative methods are found 15 and 16 mm for Staphylococcus aureus, 9 and 7 mm for Bacillus cereus, respectively, for F4 and free Juglone. Moreover, the MIC values for qualitative methods were found 31·5 μg ml-1 for two bacteria strains. CONCLUSIONS It was found that the antibacterial activity of the Juglone nanoparticles was higher and longer than the free Juglone. Additionally, a similar antimicrobial effect with a lower Juglone amount (obtained from controlled release study) indicates that nanoparticle formulation is more effective. SIGNIFICANCE AND IMPACT OF THE STUDY The use of nanoparticle formulations of Juglone in biological systems and applications could be more beneficial than its free form due to its toxicity.
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the effects of gibberellic acid and kinetin on overcoming the effects of Juglone stress on seed germination and seedling growth
Turkish Journal of Botany, 2010Co-Authors: Irfan Terzi, İsmail KocaçalişkanAbstract:Juglone (5-hydroxy-1,4-naphthoquinone) is an allelochemical responsible for walnut allelopathy. The effects of gibberellic acid (GA3) and kinetin (KIN) on overcoming the effects of Juglone stress on seed germination and seedling growth were investigated in barley, wheat, cucumber, alfalfa, and tomato. Seeds pre-treated with plant growth regulators were used to test their effects on the alleviation of Juglone stress. It was observed that seed germination in tomato and wheat was inhibited by Juglone and that the plant growth regulators alleviated it significantly. Elongation and dry weight of the seedlings of all the species used in the study were reduced significantly by Juglone, and the plant growth regulators alleviated them. The most effective treatment was the GA3+KIN combination, which was best on seedling growth in tomato and wheat.
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Effects of Juglone on seedling growth in intact and coatless seeds of cucumber (Cucumis sativus cv. Beith Alpha).
Scientific Research and Essays, 2009Co-Authors: İsmail Kocaçalişkan, M. Ceylan, Irfan TerziAbstract:The main aim of this study was to test if the seed coat is a barrier to restrict Juglone’s entrance into the seed using intact and coatless seeds of cucumber (Cucumis sativus cv. Beith Alpha). Elongation, fresh and dry weights of cucumber seedlings were decreased significantly by Juglone in both intact and coatless seeds. Protein content in cotyledons of cucumber seedling was also decreased by Juglone. The result do not prove the seed coat barrier hypothesis Because Juglone’s inhibitory effect on seedling growth and protein content was not so much different in coatless seeds than was in intact seeds. However, in the present study, catechol and dopa oxidizing activities of polyphenol oxidase enzyme were increased by Juglone in both seedlings. The increase in the activities of this enzyme was attributed to a reaction against to allelochemical stress produced by Juglone. Key words: Cucumber, Juglone, polyphenol oxidase activity, protein content, seedling growth.
Arjang Djamali - One of the best experts on this subject based on the ideXlab platform.
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The Pin 1 inhibitor Juglone attenuates kidney fibrogenesis via Pin 1-independent mechanisms in the unilateral ureteral occlusion model
Fibrogenesis & Tissue Repair, 2010Co-Authors: Shannon Reese, Aparna Vidyasagar, Lynn Jacobson, Zeki Acun, Stephane Esnault, Debra Hullett, James S Malter, Arjang DjamaliAbstract:Background Pin 1 is a peptidyl-prolyl isomerase inhibitor related to cyclophilin A and FK506 binding protein (FKBP). Juglone (5-hydroxy-1,4-naphthoquinone) is a natural inhibitor of Pin 1 with anti-inflammatory and antifibrotic properties. We evaluated the role of Pin 1 in renal fibrogenesis by evaluating the effects of Juglone on epithelial to mesenchymal transition (EMT) and fibrogenesis in the rat unilateral ureteral obstruction (UUO) model and normal rat tubular epithelial cells (NRK52E). Results After 2 weeks of UUO, immunoblot analyses demonstrated that Juglone (0.25 and 1 mg/kg/24 h) inhibited the deposition of matrix (α-smooth muscle actin (SMA), collagen type III and vimentin) and the activation of signaling pathways involved in fibrogenesis (phospho-smad2) and stress response (phospho-heat shock protein (HSP)27). Juglone also reduced EMT (α-SMA and E-cadherin dual staining) and oxidative stress (Mn superoxide dismutase (SOD) and NAPDH oxidase 2 (Nox-2) dual staining) in the obstructed kidney. There was no difference in Pin 1 levels between treatment and control groups. Pin 1 activity was significantly decreased in obstructed kidneys regardless of treatment status. In vitro , Juglone (1 μM) significantly decreased α-SMA and p-smad levels compared to vehicle. Conclusions Juglone attenuates fibrogenesis via Pin 1-independent mechanisms in the UUO model. The antifibrotic effects of Juglone may result from the inhibition of smad2 and oxidative stress.
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the pin 1 inhibitor Juglone attenuates kidney fibrogenesis via pin 1 independent mechanisms in the unilateral ureteral occlusion model
Fibrogenesis & Tissue Repair, 2010Co-Authors: Shannon R Reese, Aparna Vidyasagar, Zeki Acun, Stephane Esnault, Debra Hullett, James S Malter, Lynn M Jacobson, Arjang DjamaliAbstract:Pin 1 is a peptidyl-prolyl isomerase inhibitor related to cyclophilin A and FK506 binding protein (FKBP). Juglone (5-hydroxy-1,4-naphthoquinone) is a natural inhibitor of Pin 1 with anti-inflammatory and antifibrotic properties. We evaluated the role of Pin 1 in renal fibrogenesis by evaluating the effects of Juglone on epithelial to mesenchymal transition (EMT) and fibrogenesis in the rat unilateral ureteral obstruction (UUO) model and normal rat tubular epithelial cells (NRK52E). After 2 weeks of UUO, immunoblot analyses demonstrated that Juglone (0.25 and 1 mg/kg/24 h) inhibited the deposition of matrix (α-smooth muscle actin (SMA), collagen type III and vimentin) and the activation of signaling pathways involved in fibrogenesis (phospho-smad2) and stress response (phospho-heat shock protein (HSP)27). Juglone also reduced EMT (α-SMA and E-cadherin dual staining) and oxidative stress (Mn superoxide dismutase (SOD) and NAPDH oxidase 2 (Nox-2) dual staining) in the obstructed kidney. There was no difference in Pin 1 levels between treatment and control groups. Pin 1 activity was significantly decreased in obstructed kidneys regardless of treatment status. In vitro, Juglone (1 μM) significantly decreased α-SMA and p-smad levels compared to vehicle. Juglone attenuates fibrogenesis via Pin 1-independent mechanisms in the UUO model. The antifibrotic effects of Juglone may result from the inhibition of smad2 and oxidative stress.
Silvia Dorn - One of the best experts on this subject based on the ideXlab platform.
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ability of the oriental fruit moth grapholita molesta lepidoptera tortricidae to detoxify Juglone the main secondary metabolite of the non host plant walnut
Journal of Chemical Ecology, 2011Co-Authors: Rafal Piskorski, Simon Ineichen, Silvia DornAbstract:Many plant species produce toxic secondary metabolites that limit attacks by herbivorous insects, and may thereby constrain insect expansion to new hosts. Walnut is a host for the codling moth Cydia pomonella, which efficiently detoxifies the main walnut defensive compound Juglone (5-hydroxy-1,4-naphthoquinone). The oriental fruit moth Grapholita molesta, which also belongs to the tribe Grapholitini, does not feed on walnut. We tested the performance of G. molesta, a highly invasive species, on artificial diets containing Juglone at levels mimicking those found in walnut over the growing season. Juglone-fed G. molesta survived relatively well to adulthood, but larval and adult body weights were reduced, and larval developmental time was prolonged in a dose-dependent fashion. Chemical analysis of frass from larvae that had been fed a Juglone-containing diet suggests that G. molesta reduces Juglone to non-toxic 1,4,5-trihydroxynaphthalene in its gut. This unexpected tolerance of G. molesta to high levels of Juglone may facilitate expansion of the host range beyond the current rosacean fruit trees used by this invasive pest.
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how the oligophage codling moth cydia pomonella survives on walnut despite its secondary metabolite Juglone
Journal of Insect Physiology, 2011Co-Authors: Rafal Piskorski, Silvia DornAbstract:Besides apple, its primary host, the codling moth Cydia pomonella uses walnut as a secondary host. Abundance of toxic naphthoquinones, among which Juglone prevails, does not restrain this economically important pest insect from infesting walnut, but processes underlying the suitability of this host were yet unknown. Larvae feeding on an artificial diet supplemented with Juglone at naturally occurring concentrations survived to adulthood at a similarly high proportion as those in the Juglone-devoid control. However, their development time was prolonged, their weight gain was reduced, and adult sex ratio was distorted. Results from the natural system with walnut and apple fruits were in line with data gained on artificial diet. Remarkably, a twofold increase of the maximal Juglone content reported from the walnut husk was lethal to the larvae. Chemical analyses showed that larvae feeding on the artificial diet supplemented with Juglone concentrations present in walnut contained 1,4,5-trihydroxynaphthalene and excreted it in their frass, whereas the hemolymph contained neither detectable amounts of Juglone nor the product of its reduction. Hence, effective metabolism of Juglone in the intestinal system of the larvae underlies their survival on host plants containing this defensive compound.
Shibu Jose - One of the best experts on this subject based on the ideXlab platform.
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allelopathy in black walnut juglans nigra l alley cropping i spatio temporal variation in soil Juglone in a black walnut corn zea mays l alley cropping system in the midwestern usa
Plant and Soil, 1998Co-Authors: Shibu Jose, Andrew R GillespieAbstract:A study was conducted to quantify the spatial and temporal variation in soil Juglone (5-hydroxy-1,4-naphthoquinone) in a 10-year-old black walnut (Juglans nigra L.)–corn (Zea mays L.) alley cropping system. Two treatments (‘root barrier’ and ‘no barrier’) were applied to determine if soil Juglone in the alley can be minimized by preventing black walnut root growth into the alley. Although no significant seasonal variation in soil Juglone existed, a distinct spatial pattern was observed. Juglone concentration decreased as much as 80% as the distance increased to 4.25 m from the tree row. Installation of polyethylene root barriers minimized Juglone concentration to trace levels in the alley. However, this treatment increased Juglone levels within the tree row as compared to the ‘no barrier’ treatment, probably as a result of increased rooting density within a limited volume of soil.
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allelopathy in black walnut juglans nigra l alley cropping ii effects of Juglone on hydroponically grown corn zea mays l and soybean glycine max l merr growth and physiology
Plant and Soil, 1998Co-Authors: Shibu Jose, Andrew R GillespieAbstract:We conducted an experiment to investigate the effects of Juglone (5-hydroxy-1, 4-napthoquinone) on the growth and physiology of hydroponically grown corn (Zea mays L.) and soybean (Glycine max L. Merr.) seedlings. Three different concentrations of Juglone (10-6 M, 10-5 M, and 10-4 M) along with a control were applied. Within 3 days, Juglone exhibited significant inhibitory effects on all measured variables including shoot and root relative growth rates (RGRs and RGRr), leaf photosynthesis (Pnet), transpiration (E), stomatal conductance (gs), and leaf and root respiration. In general, soybean was found to be more sensitive to Juglone than corn. RGRr was the most inhibited variable for both species, and reductions of 86.5 and 99% were observed in corn and soybean, respectively, with 10-4 M Juglone concentrations. Among the physiological variables measured, Pnet showed the greatest impact of toxicity though the other physiological parameters were also impacted. We conclude that both corn and soybean are sensitive to Juglone and observed growth reductions in corn and soybean in black walnut alley cropping may partly be due to Juglone phytotoxicity. Determination of actual phytotoxicity will require quantification of soil solution Juglone levels, particularly in areas where soil solid-phase levels are high in close proximity to trees.
