Journal of Macromolecular Science Physics, Jan 19, 2011
The electrospinning technique has attracted significant research attention because of its various... more The electrospinning technique has attracted significant research attention because of its various potential applications and simplicity of manufacturing fibers of diameter from several micrometers to nanometer range. However, the methods for controlling the shape, structure, and uniformity of electrospun fibers have not yet been fully investigated. In this research electrospinning instabilities, such as cyclical electrospinning fluctuation and multi-jet ejections, which are closely related to the corresponding nanofiber deposition, were investigated for various polymer solution concentrations. The cyclical electrospinning fluctuation was evaluated with an image analysis program integrated with an image acquisition system that we developed. Two different drop size fluctuations of the cyclical process of the drop formation were observed.
The electrospinning technique has attracted significant research attention because of its various... more The electrospinning technique has attracted significant research attention because of its various potential applications and simplicity of manufacturing fibers of diameter from several micrometers to nanometer range. However, the methods for controlling the shape, structure, and uniformity of electrospun fibers have not yet been fully investigated. In this research electrospinning instabilities, such as cyclical electrospinning fluctuation and multi-jet ejections, which are closely related to the corresponding nanofiber deposition, were investigated for various polymer solution concentrations. The cyclical electrospinning fluctuation was evaluated with an image analysis program integrated with an image acquisition system that we developed. Two different drop size fluctuations of the cyclical process of the drop formation were observed.
The electrospinning technique has attracted significant research attention because of its various... more The electrospinning technique has attracted significant research attention because of its various potential applications and simplicity of manufacturing fibers of diameter from several micrometers to nanometer range. However, the methods for controlling the shape, structure, and uniformity of electrospun fibers have not yet been fully investigated. In this research electrospinning instabilities, such as cyclical electrospinning fluctuation and multi-jet ejections, which are closely related to the corresponding nanofiber deposition, were investigated for various polymer solution concentrations. The cyclical electrospinning fluctuation was evaluated with an image analysis program integrated with an image acquisition system that we developed. Two different drop size fluctuations of the cyclical process of the drop formation were observed.
Matrix metalloproteinases (MMPs) are crucial extracellular matrices degrading enzymes that take i... more Matrix metalloproteinases (MMPs) are crucial extracellular matrices degrading enzymes that take important roles in metastasis of cancer progression as well as other significant conditions such as oxidative stress and hepatic fibrosis. Natural products are on the rise for their potential to provide remarkable health benefits. In this context, halophytes have been of interest in the nutraceutical field with reported instances of isolation of bioactive compounds. In this study, Limonium tetragonum, an edible halophyte, was studied for its ability to inhibit MMP-2 and -9 using HT1080 fibrosarcoma cells. Results showed that L. tetragonum extract was able to inhibit the enzymatic activity and mRNA expression of MMP-2 and -9 according to gelatin zymography and RT-PCR assays, respectively, but it was not able to significantly change the MMP pathway related factors such as tissue inhibitors of metalloproteinases. Also, Mitogen-activated protein kinases pathway-related protein levels and thei...
Matrix metalloproteinases (MMPs) are crucial extracellular matrices degrading enzymes that have i... more Matrix metalloproteinases (MMPs) are crucial extracellular matrices degrading enzymes that have important roles in metastasis of cancer progression as well as other significant conditions such as oxidative stress and hepatic fibrosis. Marine plants are on the rise for their potential to provide natural products that exhibit remarkable health benefits. In this context, brown algae species have been of much interest in the pharmaceutical field with reported instances of isolation of bioactive compounds against tumor growth and MMP activity. In this study, eight different brown algae species were harvested, and their extracts were compared in regard to their anti-MMP effects. According to gelatin zymography results, Ecklonia cava, Ecklonia bicyclis, and Ishige okamurae showed higher inhibitory effects than the other samples on MMP-2 and -9 activity at the concentrations of 10, 50, and 100 μg/mL. However, only I. okamurae was able to regulate the MMP activity through the expression of M...
Journal of photochemistry and photobiology. B, Biology, Jan 25, 2015
Although ultraviolet B (UVB) has a low level of skin penetration, it readily results in epidermal... more Although ultraviolet B (UVB) has a low level of skin penetration, it readily results in epidermal sunburn of keratinocytes that are destined to apoptosis after sun expose, and leads to DNA damage. Dioxinodehydroeckol (DHE), a phlorotannin from Ecklonia cava has been explored for its preventive activity against UVB-induced apoptosis in human keratinocyte (HaCaT) cells; however, the protective effects of treatment with low doses of DHE on UVB-damaged cells post-UVB exposure and their underlying mechanisms still remain unclear. The HaCaT cells were exposed to 20mJcm(-2) of UVB irradiation which is the minimal erythema dose (MED) for individuals to be able to tan, and the expression levels of Bax/Bcl-2 and caspase-3,-8, -9 which are associated genes with apoptosis were investigated when we either treated cells with DHE doses after UVB irradiation or exposed them to UVB only. Our results suggest insight into proposed mechanistic pathway of protective activity of DHE on the HaCaT cells fr...
The inhibitory effect of three chromones 1-3 and two coumarins 4-5 on the production of nitric ox... more The inhibitory effect of three chromones 1-3 and two coumarins 4-5 on the production of nitric oxide (NO) was evaluated in LPS-induced RAW 264.7 macrophage cells. Among the compounds tested heterocarpin (1), a furochromone, significantly inhibited its production in a dose-dependent manner. In addition, heterocarpin suppressed prostaglandin E2 (PGE2) production and expression of cytokines such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6).
Osteoporosis, a prevalent bone disease in an aging population, is considered to be closely relate... more Osteoporosis, a prevalent bone disease in an aging population, is considered to be closely related to osteoblastogenesis and adipogenesis. As a part of an ongoing trend to develop natural substances that attenuate osteoporotic conditions, edible brown algae E. cava and its bioactive constituents were tested for their effects on adipogenic differentiation in 3T3-L1 fibroblasts and osteoblast differentiation in MC3T3-E1 pre-osteoblasts. Following an activity-based isolation, three phlorotannin derivatives, triphlorethol-A (1), eckol (2) and dieckol (3), were isolated. Anti-adipogenesis effect of phlorotannins at the concentration of 20 µM was observed by reduced lipid accumulation and the suppressed expression of adipogenic differentiation markers. In addition, isolated phlorotannins successfully enhanced the osteoblast differentiation as indicated by increased alkaline phosphatase activity along with raised levels of osteoblastogenesis indicators and intracellular calcification at th...
ABSTRACT Brown alga Sargassum siliquanstrum was fermented by isolated lactic acid bacteria includ... more ABSTRACT Brown alga Sargassum siliquanstrum was fermented by isolated lactic acid bacteria including Weissella sp. SH-1, Lactobacillus sp. SH-1, Leuconostoc sp. SH-1, and Streptococcus sp. SH-1, which could efficiently utilize its biologically active materials. Total polyphenol contents, total flavonoid contents and angiotensin converting enzyme inhibitory activities were measured after confirmation of pH and 2,2-diphenylpicrylhydrazyl (DPPH) radical scavenging activities. pH and DPPH radical scavenging activities plateaued after 2 days fermentation for each bacterium. Fermentation without algal debris showed better biological activities than fermentation with debris. Fermentation increased DPPH radical scavenging activities from 3.13% to 16.85% compared with non-fermented condition, with Lactobacillus sp. SH-1 being the most efficient. Weissella sp. SH-1 and Leuconostoc sp. SH-1 increased total polyphenol contents by 18.43% and total flavonoid contents by 5.70%, respectively, compared with non-fermented condition. Fermentation by Lactobacillus sp. SH-1 showed the highest angiotensin converting enzyme inhibitory activity (73.93%). Biological activities of S. siliquanstrum were upgraded by isolated lactic acid bacteria, which might be exploited in the development of functional materials or healthy drink products.
Crude extracts of Limonium tetragonum and their solvent-partitioned fractions were evaluated for ... more Crude extracts of Limonium tetragonum and their solvent-partitioned fractions were evaluated for their potential to scavenge authentic , and derived from 3-morpholinosydnonimine (SIN-1). Four flavonol glycosides (1-4) were isolated by activity-guided separation. Their chemical structures were elucidated by extensive 2 D NMR experiments and by comparison with published spectral data. These compounds were also estimated for their peroxynitrite scavenging effects. The scavenging ratios of compounds 1-4 on authentic were 56, 37, 56, and 54%, respectively, at a concentration of 1 . On the other hand, the inbihition ratios of compounds 1-4 against generation from SIN-1 were 59, 39, 44, and 54% at the same concentration, respectively.
As a part of ongoing research to elucidate and characterize antioxidant and anti-inflammatory nut... more As a part of ongoing research to elucidate and characterize antioxidant and anti-inflammatory nutraceuticals, solvent-partitioned fractions from Spergularia marina were tested for their ability to scavenge radicals and suppress inflammation. The results of the 2',7'-dichlorofluorescein diacetate assay indicate that solvent-partitioned fractions from S. marina scavenged intracellular radicals in H2O2-stimulated mouse macrophages. The tested fractions decreased the generation of nitric oxide (NO) and the expression of inflammation mediators, namely, inducible nitric oxide synthase (iNOS) and interleukin (IL)-6, by lipopolysaccharide (LPS)-induced mouse macrophages, indicating that S. marina decreases inflammation. Among all tested fractions [i.e., H2O, n-buthanol (n-BuOH), 85% aqueous methanol (aq. MeOH), and n-hexane], the 85% aq. MeOH fraction showed the strongest antioxidant and anti-inflammatory response. The 85% aq. MeOH fraction scavenged 80% of the free radicals produce...
As a part of ongoing research to develop antioxidant and anti-inflammatory nutraceuticals, an eth... more As a part of ongoing research to develop antioxidant and anti-inflammatory nutraceuticals, an ethanolic extract of Spergularia marina Griseb. was tested for its ability to scavenge radicals and suppress inflammation. The extract was able to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, and superoxide radicals, respectively, in cell-free environments as well as intracellular radicals in H2O2-stimulated mouse macrophages. Inflammation in mouse macrophages induced by lipopolysaccharides was suppressed by S. marina according to the measurement of nitric oxide generation and expression of inflammatory cytokines, i.e. tumour necrosis factor-α (TNFα), interleukin (IL)-1β, and IL-6. The anti-inflammatory effect of S. marina was substantiated by the finding that the expression of the inflammatory modulators, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), was significantly decreased. The chemical composition of S. marina was evaluated by FT-IR analysis of the extract indicating the presence of polyphenols and flavonoids. In conclusion, S. marina is suggested as a novel source for antioxidant and anti-inflammatory agents.
Journal of Macromolecular Science Physics, Jan 19, 2011
The electrospinning technique has attracted significant research attention because of its various... more The electrospinning technique has attracted significant research attention because of its various potential applications and simplicity of manufacturing fibers of diameter from several micrometers to nanometer range. However, the methods for controlling the shape, structure, and uniformity of electrospun fibers have not yet been fully investigated. In this research electrospinning instabilities, such as cyclical electrospinning fluctuation and multi-jet ejections, which are closely related to the corresponding nanofiber deposition, were investigated for various polymer solution concentrations. The cyclical electrospinning fluctuation was evaluated with an image analysis program integrated with an image acquisition system that we developed. Two different drop size fluctuations of the cyclical process of the drop formation were observed.
The electrospinning technique has attracted significant research attention because of its various... more The electrospinning technique has attracted significant research attention because of its various potential applications and simplicity of manufacturing fibers of diameter from several micrometers to nanometer range. However, the methods for controlling the shape, structure, and uniformity of electrospun fibers have not yet been fully investigated. In this research electrospinning instabilities, such as cyclical electrospinning fluctuation and multi-jet ejections, which are closely related to the corresponding nanofiber deposition, were investigated for various polymer solution concentrations. The cyclical electrospinning fluctuation was evaluated with an image analysis program integrated with an image acquisition system that we developed. Two different drop size fluctuations of the cyclical process of the drop formation were observed.
The electrospinning technique has attracted significant research attention because of its various... more The electrospinning technique has attracted significant research attention because of its various potential applications and simplicity of manufacturing fibers of diameter from several micrometers to nanometer range. However, the methods for controlling the shape, structure, and uniformity of electrospun fibers have not yet been fully investigated. In this research electrospinning instabilities, such as cyclical electrospinning fluctuation and multi-jet ejections, which are closely related to the corresponding nanofiber deposition, were investigated for various polymer solution concentrations. The cyclical electrospinning fluctuation was evaluated with an image analysis program integrated with an image acquisition system that we developed. Two different drop size fluctuations of the cyclical process of the drop formation were observed.
Matrix metalloproteinases (MMPs) are crucial extracellular matrices degrading enzymes that take i... more Matrix metalloproteinases (MMPs) are crucial extracellular matrices degrading enzymes that take important roles in metastasis of cancer progression as well as other significant conditions such as oxidative stress and hepatic fibrosis. Natural products are on the rise for their potential to provide remarkable health benefits. In this context, halophytes have been of interest in the nutraceutical field with reported instances of isolation of bioactive compounds. In this study, Limonium tetragonum, an edible halophyte, was studied for its ability to inhibit MMP-2 and -9 using HT1080 fibrosarcoma cells. Results showed that L. tetragonum extract was able to inhibit the enzymatic activity and mRNA expression of MMP-2 and -9 according to gelatin zymography and RT-PCR assays, respectively, but it was not able to significantly change the MMP pathway related factors such as tissue inhibitors of metalloproteinases. Also, Mitogen-activated protein kinases pathway-related protein levels and thei...
Matrix metalloproteinases (MMPs) are crucial extracellular matrices degrading enzymes that have i... more Matrix metalloproteinases (MMPs) are crucial extracellular matrices degrading enzymes that have important roles in metastasis of cancer progression as well as other significant conditions such as oxidative stress and hepatic fibrosis. Marine plants are on the rise for their potential to provide natural products that exhibit remarkable health benefits. In this context, brown algae species have been of much interest in the pharmaceutical field with reported instances of isolation of bioactive compounds against tumor growth and MMP activity. In this study, eight different brown algae species were harvested, and their extracts were compared in regard to their anti-MMP effects. According to gelatin zymography results, Ecklonia cava, Ecklonia bicyclis, and Ishige okamurae showed higher inhibitory effects than the other samples on MMP-2 and -9 activity at the concentrations of 10, 50, and 100 μg/mL. However, only I. okamurae was able to regulate the MMP activity through the expression of M...
Journal of photochemistry and photobiology. B, Biology, Jan 25, 2015
Although ultraviolet B (UVB) has a low level of skin penetration, it readily results in epidermal... more Although ultraviolet B (UVB) has a low level of skin penetration, it readily results in epidermal sunburn of keratinocytes that are destined to apoptosis after sun expose, and leads to DNA damage. Dioxinodehydroeckol (DHE), a phlorotannin from Ecklonia cava has been explored for its preventive activity against UVB-induced apoptosis in human keratinocyte (HaCaT) cells; however, the protective effects of treatment with low doses of DHE on UVB-damaged cells post-UVB exposure and their underlying mechanisms still remain unclear. The HaCaT cells were exposed to 20mJcm(-2) of UVB irradiation which is the minimal erythema dose (MED) for individuals to be able to tan, and the expression levels of Bax/Bcl-2 and caspase-3,-8, -9 which are associated genes with apoptosis were investigated when we either treated cells with DHE doses after UVB irradiation or exposed them to UVB only. Our results suggest insight into proposed mechanistic pathway of protective activity of DHE on the HaCaT cells fr...
The inhibitory effect of three chromones 1-3 and two coumarins 4-5 on the production of nitric ox... more The inhibitory effect of three chromones 1-3 and two coumarins 4-5 on the production of nitric oxide (NO) was evaluated in LPS-induced RAW 264.7 macrophage cells. Among the compounds tested heterocarpin (1), a furochromone, significantly inhibited its production in a dose-dependent manner. In addition, heterocarpin suppressed prostaglandin E2 (PGE2) production and expression of cytokines such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6).
Osteoporosis, a prevalent bone disease in an aging population, is considered to be closely relate... more Osteoporosis, a prevalent bone disease in an aging population, is considered to be closely related to osteoblastogenesis and adipogenesis. As a part of an ongoing trend to develop natural substances that attenuate osteoporotic conditions, edible brown algae E. cava and its bioactive constituents were tested for their effects on adipogenic differentiation in 3T3-L1 fibroblasts and osteoblast differentiation in MC3T3-E1 pre-osteoblasts. Following an activity-based isolation, three phlorotannin derivatives, triphlorethol-A (1), eckol (2) and dieckol (3), were isolated. Anti-adipogenesis effect of phlorotannins at the concentration of 20 µM was observed by reduced lipid accumulation and the suppressed expression of adipogenic differentiation markers. In addition, isolated phlorotannins successfully enhanced the osteoblast differentiation as indicated by increased alkaline phosphatase activity along with raised levels of osteoblastogenesis indicators and intracellular calcification at th...
ABSTRACT Brown alga Sargassum siliquanstrum was fermented by isolated lactic acid bacteria includ... more ABSTRACT Brown alga Sargassum siliquanstrum was fermented by isolated lactic acid bacteria including Weissella sp. SH-1, Lactobacillus sp. SH-1, Leuconostoc sp. SH-1, and Streptococcus sp. SH-1, which could efficiently utilize its biologically active materials. Total polyphenol contents, total flavonoid contents and angiotensin converting enzyme inhibitory activities were measured after confirmation of pH and 2,2-diphenylpicrylhydrazyl (DPPH) radical scavenging activities. pH and DPPH radical scavenging activities plateaued after 2 days fermentation for each bacterium. Fermentation without algal debris showed better biological activities than fermentation with debris. Fermentation increased DPPH radical scavenging activities from 3.13% to 16.85% compared with non-fermented condition, with Lactobacillus sp. SH-1 being the most efficient. Weissella sp. SH-1 and Leuconostoc sp. SH-1 increased total polyphenol contents by 18.43% and total flavonoid contents by 5.70%, respectively, compared with non-fermented condition. Fermentation by Lactobacillus sp. SH-1 showed the highest angiotensin converting enzyme inhibitory activity (73.93%). Biological activities of S. siliquanstrum were upgraded by isolated lactic acid bacteria, which might be exploited in the development of functional materials or healthy drink products.
Crude extracts of Limonium tetragonum and their solvent-partitioned fractions were evaluated for ... more Crude extracts of Limonium tetragonum and their solvent-partitioned fractions were evaluated for their potential to scavenge authentic , and derived from 3-morpholinosydnonimine (SIN-1). Four flavonol glycosides (1-4) were isolated by activity-guided separation. Their chemical structures were elucidated by extensive 2 D NMR experiments and by comparison with published spectral data. These compounds were also estimated for their peroxynitrite scavenging effects. The scavenging ratios of compounds 1-4 on authentic were 56, 37, 56, and 54%, respectively, at a concentration of 1 . On the other hand, the inbihition ratios of compounds 1-4 against generation from SIN-1 were 59, 39, 44, and 54% at the same concentration, respectively.
As a part of ongoing research to elucidate and characterize antioxidant and anti-inflammatory nut... more As a part of ongoing research to elucidate and characterize antioxidant and anti-inflammatory nutraceuticals, solvent-partitioned fractions from Spergularia marina were tested for their ability to scavenge radicals and suppress inflammation. The results of the 2',7'-dichlorofluorescein diacetate assay indicate that solvent-partitioned fractions from S. marina scavenged intracellular radicals in H2O2-stimulated mouse macrophages. The tested fractions decreased the generation of nitric oxide (NO) and the expression of inflammation mediators, namely, inducible nitric oxide synthase (iNOS) and interleukin (IL)-6, by lipopolysaccharide (LPS)-induced mouse macrophages, indicating that S. marina decreases inflammation. Among all tested fractions [i.e., H2O, n-buthanol (n-BuOH), 85% aqueous methanol (aq. MeOH), and n-hexane], the 85% aq. MeOH fraction showed the strongest antioxidant and anti-inflammatory response. The 85% aq. MeOH fraction scavenged 80% of the free radicals produce...
As a part of ongoing research to develop antioxidant and anti-inflammatory nutraceuticals, an eth... more As a part of ongoing research to develop antioxidant and anti-inflammatory nutraceuticals, an ethanolic extract of Spergularia marina Griseb. was tested for its ability to scavenge radicals and suppress inflammation. The extract was able to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, and superoxide radicals, respectively, in cell-free environments as well as intracellular radicals in H2O2-stimulated mouse macrophages. Inflammation in mouse macrophages induced by lipopolysaccharides was suppressed by S. marina according to the measurement of nitric oxide generation and expression of inflammatory cytokines, i.e. tumour necrosis factor-α (TNFα), interleukin (IL)-1β, and IL-6. The anti-inflammatory effect of S. marina was substantiated by the finding that the expression of the inflammatory modulators, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), was significantly decreased. The chemical composition of S. marina was evaluated by FT-IR analysis of the extract indicating the presence of polyphenols and flavonoids. In conclusion, S. marina is suggested as a novel source for antioxidant and anti-inflammatory agents.
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