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Jae Sue Choi - One of the best experts on this subject based on the ideXlab platform.
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characterizing Eckol as a therapeutic aid a systematic review
Marine Drugs, 2019Co-Authors: Bandana Manandhar, Pradeep Paudel, Hyun Ah Jung, Su Hui Seong, Jae Sue ChoiAbstract:The marine biosphere is a treasure trove of natural bioactive secondary metabolites and the richest source of structurally diverse and unique compounds, such as phlorotannins and halo-compounds, with high therapeutic potential. Eckol is a precursor compound representing the dibenzo-1,4-dioxin class of phlorotannins abundant in the Ecklonia species, which are marine brown algae having a ubiquitous distribution. In search of compounds having biological activity from macro algae during the past three decades, this particular compound has attracted massive attention for its multiple therapeutic properties and health benefits. Although several varieties of marine algae, seaweed, and phlorotannins have already been well scrutinized, Eckol deserves a place of its own because of the therapeutic properties it possesses. The relevant information about this particular compound has not yet been collected in one place; therefore, this review focuses on its biological applications, including its potential health benefits and possible applications to restrain diseases leading to good health. The facts compiled in this review could contribute to novel insights into the functions of Eckol and potentially enable its use in different uninvestigated fields.
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Eckol as a potential therapeutic against neurodegenerative diseases targeting dopamine d d receptors
Marine Drugs, 2019Co-Authors: Pradeep Paudel, Hyun Ah Jung, Su Hui Seong, Suhyun Park, Jae Sue ChoiAbstract:The G protein-coupled receptor (GPCR) family of proteins comprises signaling proteins that mediate cellular responses to various hormones and neurotransmitters, and serves as a prime target for drug discovery. Towards our goal of discovering secondary metabolites from natural sources that can function as neuronal drugs, we evaluated the modulatory effect of Eckol on various GPCRs via cell-based functional assays. In addition, we conducted in silico predictions to obtain molecular insights into the functional effects of Eckol. Functional assays revealed that Eckol had a concentration-dependent agonist effect on dopamine D₃ and D₄ receptors. The half maximal effective concentration (EC50) of Eckol for the dopamine D₃ and D₄ receptors was 48.62 ± 3.21 and 42.55 ± 2.54 µM, respectively, while the EC50 values of dopamine as a reference agonist for these two receptors were 2.9 and 3.3 nM, respectively. In silico studies revealed that a low binding energy in addition to hydrophilic, hydrophobic, π⁻alkyl, and π⁻π T-shaped interactions are potential mechanisms by which Eckol binds to the dopamine receptors to exert its agonist effects. Molecular dynamics (MD) simulation revealed that Phe346 of the dopamine receptors is important for binding of Eckol, similar to eticlopride and dopamine. Our results collectively suggest that Eckol is a potential D₃/D₄ agonist for the management of neurodegenerative diseases, such as Parkinson's disease.
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Eckol as a Potential Therapeutic against Neurodegenerative Diseases Targeting Dopamine D3/D4 Receptors
MDPI AG, 2019Co-Authors: Pradeep Paudel, Hyun Ah Jung, Su Hui Seong, Suhyun Park, Jae Sue ChoiAbstract:The G protein-coupled receptor (GPCR) family of proteins comprises signaling proteins that mediate cellular responses to various hormones and neurotransmitters, and serves as a prime target for drug discovery. Towards our goal of discovering secondary metabolites from natural sources that can function as neuronal drugs, we evaluated the modulatory effect of Eckol on various GPCRs via cell-based functional assays. In addition, we conducted in silico predictions to obtain molecular insights into the functional effects of Eckol. Functional assays revealed that Eckol had a concentration-dependent agonist effect on dopamine D3 and D4 receptors. The half maximal effective concentration (EC50) of Eckol for the dopamine D3 and D4 receptors was 48.62 ± 3.21 and 42.55 ± 2.54 µM, respectively, while the EC50 values of dopamine as a reference agonist for these two receptors were 2.9 and 3.3 nM, respectively. In silico studies revealed that a low binding energy in addition to hydrophilic, hydrophobic, π⁻alkyl, and π⁻π T-shaped interactions are potential mechanisms by which Eckol binds to the dopamine receptors to exert its agonist effects. Molecular dynamics (MD) simulation revealed that Phe346 of the dopamine receptors is important for binding of Eckol, similar to eticlopride and dopamine. Our results collectively suggest that Eckol is a potential D3/D4 agonist for the management of neurodegenerative diseases, such as Parkinson’s disease
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Evaluation of the inhibitory effects of Eckol and diEckol isolated from edible brown alga Eisenia bicyclis on human monoamine oxidases A and B
Archives of Pharmacal Research, 2017Co-Authors: Hyun Ah Jung, Anupom Roy, Jee H. Jung, Jae Sue ChoiAbstract:Eckol and diEckol are important phlorotannins found in edible brown algae including Eisenia bicyclis, Ecklonia stolonifera, and others. Inhibition of monoamine oxidase (MAO) play an important role in the early management of Parkinson’s disease (PD). The aim of this study was to determine the effectiveness of Eckol and diEckol isolated from the methanolic extract of E. bicyclis against PD by the inhibition of human MAO-A and MAO-B ( h MAO-A and h MAO-B). A sensitive enzyme-based chemiluminescent assay and kinetics methods were used to investigate enzyme inhibition and mode of inhibition. A molecular docking simulation was performed to clarify the binding characteristics of Eckol and diEckol to h MAO-A and h MAO-B. The results suggested that methanolic extract of E. bicyclis and its isolated phlorotannins, Eckol and diEckol, have potent inhibitory activity against h MAO-A and h MAO-B. The enzyme-based kinetics results demonstrated Eckol mixed and non-competitive inhibition of h MAO-A and h MAO-B, respectively, while diEckol non-competitively inhibited both h MAOs. Molecular docking simulation predicted that Eckol and diEckol exhibit higher binding affinity towards h MAO-A and h MAO-B through hydrogen bonding and hydrophobic interactions. These findings implicate Eckol and diEckol as inhibitors of h MAOs that might be of potential value in the management of PD.
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phlorotannins isolated from the edible brown alga ecklonia stolonifera exert anti adipogenic activity on 3t3 l1 adipocytes by downregulating c ebpα and pparγ
Fitoterapia, 2014Co-Authors: Hyun Ah Jung, Hee Jin Jung, Hyun Young Jeong, Hyun Ju Kwon, Md Yousof Ali, Jae Sue ChoiAbstract:Abstract The dramatic increase in obesity-related diseases emphasizes the need to elucidate the cellular and molecular mechanisms underlying fat metabolism. Inhibition of adipocyte differentiation has been suggested to be an important strategy for preventing or treating obesity. In our previous study, we characterized an Ecklonia stolonifera extract and non-polar fractions thereof, including dichloromethane and ethyl acetate fractions. We showed that these fractions inhibited adipocyte differentiation and lipid formation/accumulation in 3T3-L1 preadipocytes, as assessed by Oil Red O staining. As part of our ongoing search for anti-obesity agents derived from E. stolonifera, in this work, we characterized five known phlorotannins, including phloroglucinol, Eckol, diEckol, dioxinodehydroEckol, and phlorofucofuroEckol A, all of which were isolated from the active ethyl acetate fraction of E. stolonifera. We determined the chemical structures of these phlorotannins through comparisons of published nuclear magnetic resonance (NMR) spectral data. Furthermore, we screened these phlorotannins for their abilities to inhibit adipogenesis over a range of concentrations (12.5–100 μM). Of these five phlorotannins, phloroglucinol, Eckol, and phlorofucofuroEckol A significantly concentration-dependently inhibited lipid accumulation in 3T3-L1 cells without affecting cell viability. In addition, the five isolated phlorotannins also significantly reduced the expression levels of several adipocyte marker genes, including proliferator activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα), although they did so to different extents. These results suggest that the molecular weight of a phlorotannin is an important factor affecting its ability to inhibit adipocyte differentiation and modulate the expression levels of adipocyte marker genes.
Johannes Van Staden - One of the best experts on this subject based on the ideXlab platform.
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Bioactive molecules derived from smoke and seaweed Ecklonia maxima showing phytohormone-like activity in Spinacia oleracea L.
New biotechnology, 2018Co-Authors: Manoj G. Kulkarni, Kannan R.r. Rengasamy, S.c. Pendota, Jiří Grúz, Lenka Plačková, Ondřej Novák, Karel Doležal, Johannes Van StadenAbstract:Bioactive compounds such as karrikinolide (KAR1 from smoke) and Eckol (from the seaweed Ecklonia maxima) show promising effects on several important crop plants. These plant growth-stimulating organic biomolecules, along with crude extracts (smoke-water and Kelpak® product prepared from Ecklonia maxima), were tested on spinach plants. Eckol sprayed at 10-6 M significantly increased all the growth and biochemical parameters examined compared to control spinach plants. All tested plant growth biostimulants significantly increased total chlorophyll, carotenoids and protein content of spinach leaves. The cytokinin profile of spinach plants was also determined. Cis-zeatin, dihydrozeatin and isopentenyladenine types of cytokinins were promoted by both smoke- and seaweed-based biostimulants. In comparison to the control plants, the level of free sinapic acid was greater in all spinach plants treated with these biostimulants. The application of these biostimulants can help spinach crop by improving growth, yield and nutritional quality; moreover, they are organic and cost-effective.
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enhancing growth phytochemical constituents and aphid resistance capacity in cabbage with foliar application of Eckol a biologically active phenolic molecule from brown seaweed
New Biotechnology, 2016Co-Authors: Kannan R.r. Rengasamy, S.c. Pendota, M G Kulkarni, Johannes Van StadenAbstract:Although foliar application of seaweed extracts on plant growth and development has and is extensively studied, reliable knowledge and understanding of the mode of action of particular compound(s) responsible for enhancing plant growth is lacking. A brown seaweed Ecklonia maxima is widely used commercially as a biostimulant to improve plant growth and crop protection. Eckol, a phenolic compound isolated from E. maxima has recently shown stimulatory effects in maize, indicating its potential use as a plant biostimulant. Cabbage is a widely cultivated vegetable crop throughout the world, which requires high input of fertilizers and is susceptible to several aphid borne diseases. This study was conducted to evaluate the effect of foliar application of Eckol on the growth, phytochemical constituents and myrosinase activity (aphid resistance capacity) of commercially cultivated cabbage. Foliar application of Eckol (10(-6) M) significantly enhanced shoot and root length, shoot and root fresh and dry weight, leaf area and leaf number. This treatment also showed a significant increase in photosynthetic pigments (chlorophyll 'a', chlorophyll 'b', total chlorophyll and carotenoid) compared to the untreated plants. The levels of protein, proline and iridoid glycosides were significantly higher in cabbage leaves with Eckol treatment. All the control plants were severely infested with cabbage aphid (Brevicoryne brassicae) but no infestation was observed on the Eckol-sprayed plants, which can be attributed to an increase in myrosinase activity. This study reveals dual effects (plant growth promoting and insect repelling) of Eckol on cabbage plants that need further investigations both under field conditions and in other brassicaceous species.
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Quantification of plant growth biostimulants, phloroglucinol and Eckol, in four commercial seaweed liquid fertilizers and some by-products
Algal Research, 2016Co-Authors: Kannan R.r. Rengasamy, Manoj G. Kulkarni, H.b. Papenfus, Johannes Van StadenAbstract:Abstract Kelp species such as Ecklonia maxima are widely used as sources of liquid fertilizer for many economically important crops. Phloroglucinol and Eckol are active biomolecules isolated from the brown seaweed Ecklonia maxima. They have shown root and growth promoting activity in some crop species. Currently there are many seaweed liquid products available in the markets that are sold as plant biostimulants. In some of these products auxins, cytokinins, polyamines, gibberellins, abscisic acid and brassinosteroids have been quantified and their role in plant growth and development has been well established. But, the presence and quantification of phloroglucinol and Eckol in these products have not been determined yet. This would be useful for quality control of the products. In this study, four commercially available seaweed liquid fertilizers were analyzed for phloroglucinol and Eckol content using High Performance Liquid Chromatography (HPLC). Additionally, a seaweed dry cake product (‘Plant it’ manufactured by Kelpak® from Ecklonia maxima ) and Kelpak® cell wall paste by-product were also assessed for phloroglucinol and Eckol content. The liquid seaweed products evaluated in this study were prepared from the seaweeds Ascophyllum nodosum , Durvillaea potatorum and Ecklonia maxima . HPLC analysis of these products showed that Eckol content was greater than the known plant growth regulator phloroglucinol in three products. The amount of Eckol detected in all the samples ranged from 96 to 860 μg L − 1 . A higher quantity of both phloroglucinol and Eckol was recorded for Kelpak® in comparison to the other products. The higher levels of these two plant growth promoting biomolecules in the Kelpak® samples can be attributed to the use of cold cellular-burst technology. More studies are necessary to determine the optimum levels of phloroglucinol and Eckol required for plant growth in different liquid seaweed fertilizers.
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Eckol Improves Growth, Enzyme Activities, and Secondary Metabolite Content in Maize (Zea mays cv. Border King)
Journal of Plant Growth Regulation, 2015Co-Authors: Kannan R.r. Rengasamy, Wendy A. Stirk, Manoj G. Kulkarni, Johannes Van StadenAbstract:The effects of Eckol, a phenolic compound isolated from the seaweed Ecklonia maxima, on the growth of Zea mays cv. Border King were examined. Kernels were soaked in Eckol solution (10−6 M) for 18 h prior to planting. Additional treatments were water control and 10−6 M phloroglucinol, a known phenolic plant growth regulator. Growth parameters, photosynthetic pigments, total proteins, α-amylase and malate dehydrogenase (MDH) activities, and secondary metabolite content such as total phenolics (TPC), total flavonoids, condensed tannins, and iridoid glycosides (IG) were determined in roots and shoots after 60 days. Generally, a considerable difference in growth, enzyme activities, and secondary metabolite content were observed between the treatments. The roots of Eckol-soaked kernels yielded higher levels of proteins (124 ± 0 µg/g FW), TPC (7.0 ± 0.14 mg GAE/g DW), and IG (1.74 ± 0 mg HE/g DW) compared to the water control. The phloroglucinol treatment showed a significant (P < 0.05) increase in TPC and IG of maize roots. Kernels soaked with Eckol and phloroglucinol solutions showed enhanced α-amylase and MDH activities. In this study, Eckol treatment enhanced both growth and biochemical physiology of the maize cultivar used, possibly through synergistic effects with other plant growth hormones. The mechanism of action needs further evaluation.
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Eckol a new plant growth stimulant from the brown seaweed ecklonia maxima
Journal of Applied Phycology, 2015Co-Authors: Kannan R.r. Rengasamy, Wendy A. Stirk, M G Kulkarni, Johannes Van StadenAbstract:The seaweed concentrate Kelpak® made from the brown kelp Ecklonia maxima is used worldwide as a biostimulant for a number of agricultural crops. Plant growth regulators such as auxins, cytokinins, polyamines, gibberellins, abscisic acid, and brassinosteroids were identified from E. maxima and Kelpak®. In this study, we investigated the plant growth stimulating effects of two phlorotannins, i.e., phloroglucinol and Eckol that were recently isolated from E. maxima. The activity of isolated Eckol was compared with Kelpak® and commercially available phloroglucinol and the auxin indole-3-butyric acid (IBA). The isolated Eckol from E. maxima stimulated maize growth in terms of shoot and root elongation and number of seminal roots and exhibited improvement in the biochemical activities of α-amylase compared to Kelpak®, phloroglucinol, and IBA. Furthermore, Eckol showed auxin-like activity in the mung bean root assay at 10−5 M with an increased number of roots, shoot elongation, and seedling weight. Eckol can potentially play a significant role in increasing agricultural productivity.
Nam Ho Lee - One of the best experts on this subject based on the ideXlab platform.
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Eckol inhibits particulate matter 2 5 induced skin keratinocyte damage via mapk signaling pathway
Marine Drugs, 2019Co-Authors: Ao Xuan Zhen, Kyoung Ah Kang, Mei Jing Piao, Hee Kyoung Kang, Nam Ho Lee, Yu Jae Hyun, Pincha Devage Sameera Madushan Fernando, Mee Jung Ahn, Young Sang Koh, Jin Won HyunAbstract:Toxicity of particulate matter (PM) towards the epidermis has been well established in many epidemiological studies. It is manifested in cancer, aging, and skin damage. In this study, we aimed to show the mechanism underlying the protective effects of Eckol, a phlorotannin isolated from brown seaweed, on human HaCaT keratinocytes against PM2.5-induced cell damage. First, to elucidate the underlying mechanism of toxicity of PM2.5, we checked the reactive oxygen species (ROS) level, which contributed significantly to cell damage. Experimental data indicate that excessive ROS caused damage to lipids, proteins, and DNA and induced mitochondrial dysfunction. Furthermore, Eckol (30 μM) decreased ROS generation, ensuring the stability of molecules, and maintaining a steady mitochondrial state. The western blot analysis showed that PM2.5 promoted apoptosis-related protein levels and activated MAPK signaling pathway, whereas Eckol protected cells from apoptosis by inhibiting MAPK signaling pathway. This was further reinforced by detailed investigations using MAPK inhibitors. Thus, our results demonstrated that inhibition of PM2.5-induced cell apoptosis by Eckol was through MAPK signaling pathway. In conclusion, Eckol could protect skin HaCaT cells from PM2.5-induced apoptosis via inhibiting ROS generation.
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cytoprotective effect of Eckol against oxidative stress induced mitochondrial dysfunction involvement of the foxo3a ampk pathway
Journal of Cellular Biochemistry, 2014Co-Authors: Areum Kim, Kyoung Ah Kang, Mei Jing Piao, Ki Cheon Kim, Jian Zheng, Cheng Wen Yao, Ji Won Cha, Chang Lim Hyun, Hee Kyoung Kang, Nam Ho LeeAbstract:This study investigated the cytoprotective effect of Ecklonia cava-derived Eckol against H2O2-induced mitochondrial dysfunction in Chang liver cells. While H2O2 augmented levels of mitochondrial reactive oxygen species (ROS), Eckol decreased it. Eckol also attenuated high intracellular Ca(2+) levels stimulated by H2O2 and recovered H2O2-diminished ATP levels and succinate dehydrogenase activity. Eckol time-dependently increased the expression of manganese superoxide dismutase (Mn SOD), a mitochondrial antioxidant enzyme with cytoprotective effect against oxidative stress. Eckol recovered Mn SOD expression and activity that were decreased by H2O2. Finally, Eckol induced Mn SOD through phosphorylated AMP-activated protein kinase (AMPK) and forkhead box O3a (FoxO3a). Specific silencing RNAs (siRNAs) against FoxO3a and AMPK reduced Eckol-stimulated Mn SOD expression, and diethyldithiocarbamate (Mn SOD inhibitor) and siRNA against Mn SOD reduced the cytoprotective effect of Eckol against H2O2-provoked cell death. These results demonstrate that Eckol protects cells from mitochondrial oxidative stress by activating AMPK/FoxO3a-mediated induction of Mn SOD.
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Eckol inhibits ultraviolet b induced cell damage in human keratinocytes via a decrease in oxidative stress
Biological & Pharmaceutical Bulletin, 2012Co-Authors: Mei Jing Piao, Sungwook Chae, Nam Ho Lee, Jin Won HyunAbstract:In previous reports, the antioxidant effects of Eckol were shown to protect cells against hydrogen peroxide- and gamma ray-induced oxidative stress. In this study, the role of Eckol in protecting human skin keratinocytes (HaCaT) against UVB-induced oxidative cell damage was investigated. Also, triphlorethol-A, one of the chemical components in Ecklonia cava, and quercetin a well known antioxidant, were compared with Eckol in terms of antioxidant activity based on chemical structure. Eckol decreased UVB-induced intracellular reactive oxygen species (ROS), decreased injury to cellular components resulting from UVB-induced oxidative stress, and restored cell viability. In addition, Eckol reduced UVB-induced apoptosis by inhibiting the disruption of mitochondrial membranes. These results suggest that Eckol protects human keratinocytes against UVB-induced oxidative stress by scavenging ROS, thereby lessening injury to cellular components.
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up regulation of nrf2 mediated heme oxygenase 1 expression by Eckol a phlorotannin compound through activation of erk and pi3k akt
The International Journal of Biochemistry & Cell Biology, 2010Co-Authors: Ki Cheon Kim, Kyoung Ah Kang, Rui Zhang, Mei Jing Piao, Nam Ho Lee, Su Jae Lee, Giyoung Kim, Mi Young Kang, Youngjoon Surh, Jin Won HyunAbstract:The aim of the present study was to examine the cytoprotective effect of Eckol, a phlorotannin found in Ecklonia cava and to elucidate underlying mechanisms. Heme oxygenase-1 (HO-1) is an important antioxidant enzyme that plays a role in cytoprotection against oxidative stress. Eckol-induced HO-1 expression both at the level of mRNA and protein in Chinese hamster lung fibroblast (V79-4) cells, resulting in increased HO-1 activity. The transcription factor NF-E2-related factor 2 (Nrf2) is a critical regulator of HO-1, achieved by binding to the antioxidant response element (ARE). Eckol treatment resulted in the enhanced level of phosphorylated form, nuclear translocation, ARE-binding, and transcriptional activity of Nrf2. Extracellular regulated kinase (Erk) and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (PKB, Akt) contributed to ARE-driven HO-1 expression. Eckol activated both Erk and Akt, and treatments with U0126 (an Erk kinase inhibitor), LY294002 (a PI3K inhibitor), specific Erk1 siRNA, and Akt siRNA suppressed the Eckol-induced activation of Nrf2, resulting in a decrease in HO-1 expression. ZnPP (a HO-1 inhibitor), HO-1 siRNA, and Nrf2 siRNA markedly abolished the cytoprotective effect of Eckol against hydrogen peroxide-induced cell damage. Likewise, U0126 and LY294002 inhibited the Eckol-induced cytoprotective effect against oxidative cell damage. These studies demonstrate that Eckol attenuates oxidative stress by activating Nrf2-mediated HO-1 induction via Erk and PI3K/Akt signaling.
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Eckol protects v79 4 lung fibroblast cells against γ ray radiation induced apoptosis via the scavenging of reactive oxygen species and inhibiting of the c jun nh2 terminal kinase pathway
European Journal of Pharmacology, 2008Co-Authors: Rui Zhang, Jae Woo Park, Kyoung Ah Kang, Mei Jing Piao, Zhi Hong Wang, In Kyung Lee, Bum Joon Kim, Il Yun Jeong, Taekyun Shin, Nam Ho LeeAbstract:Abstract The radioprotective effect of Eckol against γ-ray radiation-induced oxidative stress and its possible protective mechanisms were investigated. Eckol was found to reduce the intracellular reactive oxygen species generated by γ-ray radiation. Moreover, Eckol also protected against radiation-induced cellular DNA damage and membrane lipid peroxidation, which are the main targets of radiation-induced damage. In addition, Eckol recovered the cell viability damaged by radiation via the inhibition of apoptosis. Irradiated cells with Eckol treatment reduced the expression of bax, the activation of caspase 9 and caspase 3, which were induced by radiation. However, irradiated cells with Eckol recovered the expression of bcl-2 and mitochondrial cytochrome c which were decreased by radiation. The anti-apoptotic effect of Eckol exerted via the inhibition of mitogen-activated protein kinase kinase-4 (MKK4/SEK1)-c-Jun NH 2 -terminal kinase (JNK)-activator protein 1 (AP-1) cascades induced by radiation. In summary, the results suggest that Eckol protects cells against the oxidative stress induced by radiation via the reduction of reactive oxygen species and the attenuation of activation in SEK1-JNK-AP-1 pathway.
Kannan R.r. Rengasamy - One of the best experts on this subject based on the ideXlab platform.
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Bioactive molecules derived from smoke and seaweed Ecklonia maxima showing phytohormone-like activity in Spinacia oleracea L.
New biotechnology, 2018Co-Authors: Manoj G. Kulkarni, Kannan R.r. Rengasamy, S.c. Pendota, Jiří Grúz, Lenka Plačková, Ondřej Novák, Karel Doležal, Johannes Van StadenAbstract:Bioactive compounds such as karrikinolide (KAR1 from smoke) and Eckol (from the seaweed Ecklonia maxima) show promising effects on several important crop plants. These plant growth-stimulating organic biomolecules, along with crude extracts (smoke-water and Kelpak® product prepared from Ecklonia maxima), were tested on spinach plants. Eckol sprayed at 10-6 M significantly increased all the growth and biochemical parameters examined compared to control spinach plants. All tested plant growth biostimulants significantly increased total chlorophyll, carotenoids and protein content of spinach leaves. The cytokinin profile of spinach plants was also determined. Cis-zeatin, dihydrozeatin and isopentenyladenine types of cytokinins were promoted by both smoke- and seaweed-based biostimulants. In comparison to the control plants, the level of free sinapic acid was greater in all spinach plants treated with these biostimulants. The application of these biostimulants can help spinach crop by improving growth, yield and nutritional quality; moreover, they are organic and cost-effective.
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enhancing growth phytochemical constituents and aphid resistance capacity in cabbage with foliar application of Eckol a biologically active phenolic molecule from brown seaweed
New Biotechnology, 2016Co-Authors: Kannan R.r. Rengasamy, S.c. Pendota, M G Kulkarni, Johannes Van StadenAbstract:Although foliar application of seaweed extracts on plant growth and development has and is extensively studied, reliable knowledge and understanding of the mode of action of particular compound(s) responsible for enhancing plant growth is lacking. A brown seaweed Ecklonia maxima is widely used commercially as a biostimulant to improve plant growth and crop protection. Eckol, a phenolic compound isolated from E. maxima has recently shown stimulatory effects in maize, indicating its potential use as a plant biostimulant. Cabbage is a widely cultivated vegetable crop throughout the world, which requires high input of fertilizers and is susceptible to several aphid borne diseases. This study was conducted to evaluate the effect of foliar application of Eckol on the growth, phytochemical constituents and myrosinase activity (aphid resistance capacity) of commercially cultivated cabbage. Foliar application of Eckol (10(-6) M) significantly enhanced shoot and root length, shoot and root fresh and dry weight, leaf area and leaf number. This treatment also showed a significant increase in photosynthetic pigments (chlorophyll 'a', chlorophyll 'b', total chlorophyll and carotenoid) compared to the untreated plants. The levels of protein, proline and iridoid glycosides were significantly higher in cabbage leaves with Eckol treatment. All the control plants were severely infested with cabbage aphid (Brevicoryne brassicae) but no infestation was observed on the Eckol-sprayed plants, which can be attributed to an increase in myrosinase activity. This study reveals dual effects (plant growth promoting and insect repelling) of Eckol on cabbage plants that need further investigations both under field conditions and in other brassicaceous species.
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Quantification of plant growth biostimulants, phloroglucinol and Eckol, in four commercial seaweed liquid fertilizers and some by-products
Algal Research, 2016Co-Authors: Kannan R.r. Rengasamy, Manoj G. Kulkarni, H.b. Papenfus, Johannes Van StadenAbstract:Abstract Kelp species such as Ecklonia maxima are widely used as sources of liquid fertilizer for many economically important crops. Phloroglucinol and Eckol are active biomolecules isolated from the brown seaweed Ecklonia maxima. They have shown root and growth promoting activity in some crop species. Currently there are many seaweed liquid products available in the markets that are sold as plant biostimulants. In some of these products auxins, cytokinins, polyamines, gibberellins, abscisic acid and brassinosteroids have been quantified and their role in plant growth and development has been well established. But, the presence and quantification of phloroglucinol and Eckol in these products have not been determined yet. This would be useful for quality control of the products. In this study, four commercially available seaweed liquid fertilizers were analyzed for phloroglucinol and Eckol content using High Performance Liquid Chromatography (HPLC). Additionally, a seaweed dry cake product (‘Plant it’ manufactured by Kelpak® from Ecklonia maxima ) and Kelpak® cell wall paste by-product were also assessed for phloroglucinol and Eckol content. The liquid seaweed products evaluated in this study were prepared from the seaweeds Ascophyllum nodosum , Durvillaea potatorum and Ecklonia maxima . HPLC analysis of these products showed that Eckol content was greater than the known plant growth regulator phloroglucinol in three products. The amount of Eckol detected in all the samples ranged from 96 to 860 μg L − 1 . A higher quantity of both phloroglucinol and Eckol was recorded for Kelpak® in comparison to the other products. The higher levels of these two plant growth promoting biomolecules in the Kelpak® samples can be attributed to the use of cold cellular-burst technology. More studies are necessary to determine the optimum levels of phloroglucinol and Eckol required for plant growth in different liquid seaweed fertilizers.
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Physiological role of phenolic biostimulants isolated from brown seaweed Ecklonia maxima on plant growth and development
Planta, 2015Co-Authors: Adeyemi O. Aremu, Kannan R.r. Rengasamy, Jiří Grúz, Ondřej Novák, Nqobile A. Masondo, Stephen O. Amoo, Ondřej Bíba, Michaela Šubrtová, Aleš Pěnčík, Karel DoležalAbstract:Main conclusion Eckol, a major phenolic compound isolated from brown seaweed significantly enhanced the bulb size and bioactive compounds in greenhouse-grown Eucomis autumnalis . We investigated the effect of Eckol and phloroglucinol (PG) (phenolic compounds) isolated from the brown seaweed, Ecklonia maxima (Osbeck) Papenfuss on the growth, phytochemical and auxin content in Eucomis autumnalis (Mill.) Chitt. The model plant is a popular medicinal species with increasing conservation concern. Eckol and PG were tested at 10^−5, 10^−6 and 10^−7 M using soil drench applications. After 4 months, growth parameters, phytochemical and auxin content were recorded. When compared to the control, Eckol (10^−6 M) significantly improved bulb size, fresh weight and root production while the application of PG (10^−6 M) significantly increased the bulb numbers. However, both compounds had no significant stimulatory effect on aerial organs. Bioactive phytochemicals such as p -hydroxybenzoic and ferulic acids were significantly increased in Eckol (10^−5 M) and PG (10^−6 M) treatments, compared to the control. Aerial (1,357 pmol/g DW) and underground (1,474 pmol/g DW) parts of Eckol-treated (10^−5 M) plants yielded the highest concentration of indole-3-acetic acid. Overall, Eckol and PG elicited a significant influence on the growth and physiological response in E. autumnalis . Considering the medicinal importance of E. autumnalis and the increasing strains on its wild populations, these compounds are potential tools to enhance their cultivation and growth.
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Eckol Improves Growth, Enzyme Activities, and Secondary Metabolite Content in Maize (Zea mays cv. Border King)
Journal of Plant Growth Regulation, 2015Co-Authors: Kannan R.r. Rengasamy, Wendy A. Stirk, Manoj G. Kulkarni, Johannes Van StadenAbstract:The effects of Eckol, a phenolic compound isolated from the seaweed Ecklonia maxima, on the growth of Zea mays cv. Border King were examined. Kernels were soaked in Eckol solution (10−6 M) for 18 h prior to planting. Additional treatments were water control and 10−6 M phloroglucinol, a known phenolic plant growth regulator. Growth parameters, photosynthetic pigments, total proteins, α-amylase and malate dehydrogenase (MDH) activities, and secondary metabolite content such as total phenolics (TPC), total flavonoids, condensed tannins, and iridoid glycosides (IG) were determined in roots and shoots after 60 days. Generally, a considerable difference in growth, enzyme activities, and secondary metabolite content were observed between the treatments. The roots of Eckol-soaked kernels yielded higher levels of proteins (124 ± 0 µg/g FW), TPC (7.0 ± 0.14 mg GAE/g DW), and IG (1.74 ± 0 mg HE/g DW) compared to the water control. The phloroglucinol treatment showed a significant (P < 0.05) increase in TPC and IG of maize roots. Kernels soaked with Eckol and phloroglucinol solutions showed enhanced α-amylase and MDH activities. In this study, Eckol treatment enhanced both growth and biochemical physiology of the maize cultivar used, possibly through synergistic effects with other plant growth hormones. The mechanism of action needs further evaluation.
Jin Won Hyun - One of the best experts on this subject based on the ideXlab platform.
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Eckol inhibits particulate matter 2 5 induced skin keratinocyte damage via mapk signaling pathway
Marine Drugs, 2019Co-Authors: Ao Xuan Zhen, Kyoung Ah Kang, Mei Jing Piao, Hee Kyoung Kang, Nam Ho Lee, Yu Jae Hyun, Pincha Devage Sameera Madushan Fernando, Mee Jung Ahn, Young Sang Koh, Jin Won HyunAbstract:Toxicity of particulate matter (PM) towards the epidermis has been well established in many epidemiological studies. It is manifested in cancer, aging, and skin damage. In this study, we aimed to show the mechanism underlying the protective effects of Eckol, a phlorotannin isolated from brown seaweed, on human HaCaT keratinocytes against PM2.5-induced cell damage. First, to elucidate the underlying mechanism of toxicity of PM2.5, we checked the reactive oxygen species (ROS) level, which contributed significantly to cell damage. Experimental data indicate that excessive ROS caused damage to lipids, proteins, and DNA and induced mitochondrial dysfunction. Furthermore, Eckol (30 μM) decreased ROS generation, ensuring the stability of molecules, and maintaining a steady mitochondrial state. The western blot analysis showed that PM2.5 promoted apoptosis-related protein levels and activated MAPK signaling pathway, whereas Eckol protected cells from apoptosis by inhibiting MAPK signaling pathway. This was further reinforced by detailed investigations using MAPK inhibitors. Thus, our results demonstrated that inhibition of PM2.5-induced cell apoptosis by Eckol was through MAPK signaling pathway. In conclusion, Eckol could protect skin HaCaT cells from PM2.5-induced apoptosis via inhibiting ROS generation.
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Eckol inhibits ultraviolet b induced cell damage in human keratinocytes via a decrease in oxidative stress
Biological & Pharmaceutical Bulletin, 2012Co-Authors: Mei Jing Piao, Sungwook Chae, Nam Ho Lee, Jin Won HyunAbstract:In previous reports, the antioxidant effects of Eckol were shown to protect cells against hydrogen peroxide- and gamma ray-induced oxidative stress. In this study, the role of Eckol in protecting human skin keratinocytes (HaCaT) against UVB-induced oxidative cell damage was investigated. Also, triphlorethol-A, one of the chemical components in Ecklonia cava, and quercetin a well known antioxidant, were compared with Eckol in terms of antioxidant activity based on chemical structure. Eckol decreased UVB-induced intracellular reactive oxygen species (ROS), decreased injury to cellular components resulting from UVB-induced oxidative stress, and restored cell viability. In addition, Eckol reduced UVB-induced apoptosis by inhibiting the disruption of mitochondrial membranes. These results suggest that Eckol protects human keratinocytes against UVB-induced oxidative stress by scavenging ROS, thereby lessening injury to cellular components.
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Eckol suppresses maintenance of stemness and malignancies in glioma stem like cells
Toxicology and Applied Pharmacology, 2011Co-Authors: Kyung Hwan Hyun, Jin Won Hyun, Chang Hwan Yoon, Rae Kwon Kim, Eun Jung Lim, Myung Jin Park, Yongjoon Suh, Min Jung Kim, Su Jae LeeAbstract:A subpopulation of cancer cells with stem cell properties is responsible for tumor maintenance and progression, and may contribute to resistance to anticancer treatments. Thus, compounds that target cancer stem-like cells could be usefully applied to destroy cancer. In this study, we investigated the effect of Eckol, a phlorotannin compound, on stemness and malignancies in glioma stem-like cells. To determine whether Eckol targets glioma stem-like cells, we examined whether Eckol treatment could change the expression levels of glioma stem-like cell markers and self-renewal-related proteins as well as the sphere forming ability, and the sensitivity to anticancer treatments. Alterations in the malignant properties of sphere-derived cells by Eckol were also investigated by soft-agar colony forming assay, by xenograft assay in nude mice, and by cell invasion assay. Treatment of sphere-forming glioma cells with Eckol effectively decreased the sphere formation as well as the CD133(+) cell population. Eckol treatment suppressed expression of the glioma stem-like cell markers and the self-renewal-related proteins without cell death. Moreover, treatment of glioma stem-like cells with Eckol significantly attenuated anchorage-independent growth on soft agar and tumor formation in xenograft mice. Importantly, Eckol treatment effectively reduced the resistance of glioma stem-like cells to ionizing radiation and temozolomide. Treatment of glioma stem-like cells with Eckol markedly blocked both phosphoinositide 3-kinase-Akt and Ras-Raf-1-Erk signaling pathways. These results indicate that the natural phlorotannin Eckol suppresses stemness and malignancies in glioma stem-like cells, and thereby makes glioma stem-like cells more sensitive to anticancer treatments, providing novel therapeutic strategies targeting specifically cancer stem-like cells.
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up regulation of nrf2 mediated heme oxygenase 1 expression by Eckol a phlorotannin compound through activation of erk and pi3k akt
The International Journal of Biochemistry & Cell Biology, 2010Co-Authors: Ki Cheon Kim, Kyoung Ah Kang, Rui Zhang, Mei Jing Piao, Nam Ho Lee, Su Jae Lee, Giyoung Kim, Mi Young Kang, Youngjoon Surh, Jin Won HyunAbstract:The aim of the present study was to examine the cytoprotective effect of Eckol, a phlorotannin found in Ecklonia cava and to elucidate underlying mechanisms. Heme oxygenase-1 (HO-1) is an important antioxidant enzyme that plays a role in cytoprotection against oxidative stress. Eckol-induced HO-1 expression both at the level of mRNA and protein in Chinese hamster lung fibroblast (V79-4) cells, resulting in increased HO-1 activity. The transcription factor NF-E2-related factor 2 (Nrf2) is a critical regulator of HO-1, achieved by binding to the antioxidant response element (ARE). Eckol treatment resulted in the enhanced level of phosphorylated form, nuclear translocation, ARE-binding, and transcriptional activity of Nrf2. Extracellular regulated kinase (Erk) and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (PKB, Akt) contributed to ARE-driven HO-1 expression. Eckol activated both Erk and Akt, and treatments with U0126 (an Erk kinase inhibitor), LY294002 (a PI3K inhibitor), specific Erk1 siRNA, and Akt siRNA suppressed the Eckol-induced activation of Nrf2, resulting in a decrease in HO-1 expression. ZnPP (a HO-1 inhibitor), HO-1 siRNA, and Nrf2 siRNA markedly abolished the cytoprotective effect of Eckol against hydrogen peroxide-induced cell damage. Likewise, U0126 and LY294002 inhibited the Eckol-induced cytoprotective effect against oxidative cell damage. These studies demonstrate that Eckol attenuates oxidative stress by activating Nrf2-mediated HO-1 induction via Erk and PI3K/Akt signaling.
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protective effect of phlorotannin components phloroglucinol and Eckol on radiation induced intestinal injury in mice
Phytotherapy Research, 2008Co-Authors: Changjong Moon, Jae Woo Park, Nam Ho Lee, Jin Won Hyun, Sungho Kim, Jongchoon Kim, Taekyun ShinAbstract:Components of phlorotannin, which were extracted from Ecklonia species, have been reported to have in vitro radioprotective and antioxidative effects. The radioprotective effects of two of the components of phlorotannin, phloroglucinol and Eckol, in intestinal stem cells were examined by evaluating their effects on jejunal crypt survival and apoptosis in gamma-irradiated mice. Pretreating the mice (i.p. 20 mg/kg of body weight at 12 and 36 h before irradiation) prior to irradiation with either phloroglucinol or Eckol significantly improved the survival of the jejunal crypt (p < 0.001 and p < 0.01 vs irradiation controls at 3.5 days after 8 Gy irradiation, respectively). The administration of phloroglucinol and Eckol prior to irradiation protected the intestinal crypts from radiation-induced apoptosis (p < 0.05 vs irradiation controls at 12 h after 1 Gy irradiation). Although the mechanism for this inhibitory effect remains unknown, these results showed that phloroglucinol and Eckol might be useful radioprotectors that can defend intestinal stem cells against the oxidative damage caused by gamma-irradiation.
