Byong-Tae Jeon

Konkuk University, Sŏul, Seoul, South Korea

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Publications (71)113.83 Total impact

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    ABSTRACT: Anticancer effects of lipids from a clam cultivated in Korea were investigated. Hexane extracts of Ruditapes philippinarum (R. philippinarum) exhibited the highest apoptosis rate of 40.9% at 0.5 mg/mL in PC3 cells. Hexane extracts were further separated and purified using TLC. Final lipid compounds were isolated and identified. Monounsaturated fatty acid and polyunsaturated fatty acid levels were significantly (p<0.05) increased in the purified lipid (19.71 and 34.63%), compared with the crude extract (12.96 and 15.56%). Partially purified lipid compounds exhibited an anticancer effect in several cancer cell lines, resulting in apoptosis rates in breast, lung, and liver cancer cells of 37.36, 17.78, 26.56%, respectively, at 30 µg/mL. This is the first report of an anticancer effect of a lipid extracted from R. philippinarum cultivated in Korea. © 2015, The Korean Society of Food Science and Technology and Springer Science+Business Media Dordrecht.
    No preview · Article · Dec 2015 · Food science and biotechnology
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    ABSTRACT: Numerous plants have been documented to contain phenolic compounds. Thymol is one among these phenolic compounds that possess repertoire of pharmacological activities including anti-inflammatory, anticancer, antioxidant, antibacterial and antimicrobial activities. Despite of the plethora of affects elicited by thymol, its activity profile on gastric cancer cells is not explored. In this study, we discovered that thymol exerts anticancer effects by suppressing cell growth, inducing apoptosis, producing intracellular reactive oxygen species (ROS), depolarizing mitochondrial membrane potential (MMP), and activating proapoptotic mitochondrial proteins Bax, cysteine aspartases (caspases), and poly ADP ribose polymerase (PARP) in human gastric AGS cells. The outcomes of this study displayed that thymol, via intrinsic mitochondrial pathway was responsible for inducing apoptosis in gastric AGS cells. Hence, thymol might serve as a tentative agent in the future to treat cancer.
    No preview · Article · Oct 2015 · Journal of Microbiology and Biotechnology
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    ABSTRACT: We investigated the biologically active substances contained in RVA (regrowth velvet antler) by comparing the composition of biologically active substances and antioxidant potential of different antler segments. RVA was subjected to extraction using DW (distilled water). RVA was divided into 3 segments: T-RVA (top RVA), M-RVA (middle RVA), and B-RVA (base RVA). The T-RVA section possessed the greatest amounts of uronic acid (36.251 mg/g), sulfated GAGs (sulfated glycosaminoglycans) (555.76 mg/g), sialic acid (111.276 mg/g), uridine (0.957 mg/g), uracil (1.084 mg/g), and hypoxanthine (1.2631 mg/g). In addition, the T-RVA section possessed the strongest antioxidant capacity as determined by DPPH, H 2 O 2 (hydrogen peroxide), hydroxyl, and ABTS (2,2′-azinobis-3-ethylbenzthiazoline-6-sulphonate) radical scavenging activity as well as FRAP (ferric reducing antioxidant power) and ORAC (oxygen radical absorbance capacity). The values of those were 53.44, 23.09, 34.12, 60.31, and 35.81 TE/ μ M at 1 mg/mL and 113.57 TE/ μ M at 20 μ g/mL. These results indicate that the T-RVA section possesses the greatest amount of biologically active substances and highest antioxidant potential. This is the first report on the biologically active substances and antioxidant potential of RVA.
    Preview · Article · Sep 2015
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    ABSTRACT: Aloe vera (A. vera) has been used in traditional medicine for the therapy of a variety of disorders, such as wounds and burns. However, few studies have examined the antioxidant capacities of A. vera plants during different growth periods. In order to investigate the effects of growth on antioxidant activity, A. vera was prepared from 2-, 4-, 6-, 8-, and 12-month-old aloe. The extracts from 6-month-old A. vera showed the highest contents of flavonoids (9.750 mg catechin equivalent/g extract) and polyphenols (23.375 mg gallic acid equivalent/g extract) and the highest ferric reducing antioxidant power (0.047 mM ferrous sulfate equivalent/mg extract). The extract from 6-month-old A. vera exhibited the highest free radical scavenging potential, and the lowest IC50 values were found for 2,2-diphenyl-1-picrylhydrazyl (0.26 mg/mL) and alkyl radicals (0.50 mg/mL). In addition, the extract from 6-month-old A. vera showed the greatest effects on cell viability in normal liver cells. Based on these findings, the extract from 6-month-old A. vera was examined further in order to determine its protective potential against tert-Butyl hydroperoxide (t-BHP)-induced oxidative stress. The extract from 6-month-old A. vera at a concentration of 0.25 mg/mL showed the highest protective activity against t-BHP-induced reactive oxygen species production. These findings suggested that harvesting regimens were critical in the regulation of effects of the bioactive potential of A. vera on antioxidant activity.
    No preview · Article · Sep 2015 · Journal of Microbiology and Biotechnology
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    ABSTRACT: Pancreatic β cells are highly sensitive to oxidative stress, which might play an important role in β cell death in diabetes. The protective effect of 6,6'-bieckol, a phlorotannin polyphenol compound purified from Ecklonia cava, against high glucose-induced glucotoxicity was investigated in rat insulinoma cells. High glucose (30 mM) treatment induced the death of rat insulinoma cells, but treatment with 10 or 50 μg/mL 6,6'-bieckol significantly inhibited the high glucose-induced glucotoxicity. Furthermore, treatment with 6,6'-bieckol dose-dependently reduced the level of thiobarbituric acid reactive substances, generation of intracellular reactive oxygen species, and the level of nitric oxide, all of which were increased by high glucose concentration. In addition, 6,6'-bieckol protected rat insulinoma cells from apoptosis under high-glucose conditions. These effects were associated with increased expression of the anti-apoptotic protein Bcl-2 and reduced expression of the pro-apoptotic protein Bax. These findings indicate that 6,6'-bieckol could be used as a potential nutraceutical agent offering protection against the glucotoxicity caused by hyperglycemia-induced oxidative stress associated with diabetes.
    No preview · Article · Sep 2015 · Fitoterapia
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    ABSTRACT: In the present study, we showed that recombinant ice-binding protein (rLeIBP) from Arctic yeast Glaciozyma sp. prolonged the shelf-life of Korean beef by delaying lipid peroxidation and microbial growth rates during cold storage when it was embrocated in Korean beef before freezing. In addition, glutathione (GSH) and the antioxidant enzyme activities including catalase (CAT), glutathione S-transferase (GST), glutathione peroxidase (GPX) and superoxide dismutase (SOD) were higher in the rLeIBP treated Korean beef samples than the control group containing no rLeIBP. These results indicate that the rLeIBP may be used to treat beef prior to refrigeration, since rLeIBP was shown to retard microbial growth rates as well as lipid peroxidation and improve the antioxidant enzyme activities of beef during cold storage.
    No preview · Article · Sep 2015 · PROCESS BIOCHEMISTRY
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    ABSTRACT: This study was aimed at investigating the possible mechanism of the anti-proliferative effect of taurine on B16F10 melanoma cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and neutral red assays and microscopic analysis. Apoptotic cells were detected by flow cytometry analysis. The proteins involved in apoptosis and cellular differentiation were assessed by immunoblot analysis. Taurine inhibited cell proliferation and induced cell death in B16F10 cells. In this study, taurine was used to examine whether it could be a potential chemotherapy agent for skin cancer. Our data suggest that taurine inhibits B16F10 cell proliferation by inducing apoptosis and cellular differentiation.
    No preview · Article · Apr 2015 · Advances in Experimental Medicine and Biology
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    ABSTRACT: Carvacrol is a monoterpenic phenol present in Thymus quinquecostatus Celak. The protective effects of carvacrol against tert-butyl hydroperoxide (t-BHP)-induced oxidative damage were investigated in human Chang cells. Cells treated with carvacrol extracts promoted Chang cell survival and protection was associated with stabilization of the mitochondrial membrane potential (MMP), prevention of oxidative stress-triggered reactive oxygen species (ROS), and lipid peroxidation (MDA production). In addition, Annexin V/PI, observed using Hoechst staining, indicated that carvacrol inhibited t-BHP-induced cell damage and stimulated the antioxidant capability of Chang cells due to elevation of glutathione (GSH) levels, which were reduced by t-BHP treatment. Carvacrol prevented oxidative stress-induced Chang cell damage via suppression of ROS and MDA levels, and increased GSH levels.
    No preview · Article · Apr 2015 · Food science and biotechnology
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    ABSTRACT: This study was undertaken to evaluate the antioxidant potential and protective effects of Celosia cristata L. (Family: Amaranthaceae) flower (CCF) extracts on tert-butyl-hydroperoxide (t-BHP)-induced oxidative damage in the hepatocytes of Chang cells and rat livers. In vitro, CCF extracts exhibited protective effect through their radical scavenging ability to enhance cell viability, prevent reactive oxygen species (ROS) generation, and inhibit mitochondrial membrane depolarisation in t-BHP-induced hepatotoxicity in Chang cells. In vivo, oral feeding of CCF (100mg and 500mg/kg of body weight) to rats for five consecutive days before a single dose of t-BHP (2mmol/kg, i.p.) showed a significant (p<0.05) protective effect by lowering serum levels of glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT). The extract decreased the hepatic levels of lipid peroxidation (MDA) and serum level of triglyceride (TG) against t-BHP-induced oxidative stress. These results indicate that CCF extract prevented oxidative stress-induced liver injury by enhancing hepatocyte antioxidant abilities.
    No preview · Article · Feb 2015 · Food Chemistry
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    ABSTRACT: The present study was performed to investigate the various radical scavenging activities of fermented Undaria pinnatifida by the mycelia fermentation method. U. pinnatifida was fermented with Cordyceps militaris (C. militaris) mycelia using solid culture and compared to unfermentated U. pinnatifida and C. militaris mycelia for anti-oxidant activities. The various radical scavenging activities of extracts from U. pinnatifida fermented with C. militaris mycelia (FUCM) were evaluated by electron spin resonance (ESR). The antioxidant activities of the FUCM extracts were assayed for ferric reducing antioxidant power (FRAP), 2,2'-azinobis-(3-ethybenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, and oxygen radical absorption capacity (ORAC). The free radical scavenging activity of FUCM extracts was higher than that of C. militaris mycelia or U. pinnatifida alone. FUCM extracts were significantly (p<0.05) increased up to 35 times, 10 times, and 16 times than U. pinnatifida extracts on DPPH, alkyl, and hydroxyl radical scavenging activities, respectively. These results indicate that FUCM extracts have different chemical ingredients from U. pinnatifida and could provide beneficial anti-oxidant activity.
    No preview · Article · Jan 2015 · Journal of Microbiology and Biotechnology
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    ABSTRACT: Various biological effects have been reported for sulfated chitosan oligosaccharides, but the molecular mechanisms of action of their anti-inflammatory effects are still unknown. This study aimed to evaluate the anti-inflammatory effects of sulfated chitosan oligosaccharides and to elucidate the possible mechanisms of action. The results showed that pretreated low molecular weight sulfated chitosan oligosaccharides inhibited the production of nitric oxide (NO) and inflammatory cytokines such as IL-6 and TNF-α in lipopolysaccharide (LPS)-activated RAW264.7 cells. The sulfated chitosan oligosaccharides also suppressed inducible nitric oxide synthase (iNOS), phosphorylation of JNK and translocation of p65, a subunit of NF-κB, into the nucleus by inhibiting degradation of IκB-α. Our investigation suggests sulfated chitosan oligosaccharides inhibit IL-6/TNF-α in LPS-induced macrophages, regulated by mitogen-activated protein kinases (MAPKs) pathways dependent on NF-κB activation.
    Preview · Article · Nov 2014 · Molecules
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    ABSTRACT: α-Glucosidase inhibitors are important agents for decreasing postprandial hyperglycemia. The current study examined the inhibitory effects of octaphlorethol A (OPA) isolated from Ishige foliacea, a brown alga, on α-glucosidase, and analyzed the inhibitor's binding modes using the crystal structure of α-glucosidase. The effects of OPA on postprandial blood glucose levels after meals were also investigated. The IC50 value of OPA against α-glucosidase was 0.11 mM, which is higher than that of the commercial inhibitor acarbose. For further insights, we predicted the 3D structure of α-glucosidase and used a docking algorithm to simulate binding between α-glucosidase and OPA. These molecular modeling studies were successful, and indicated that OPA interacts with Phe575, His600, Arg526, Met444, Asp542, Tyr605, Ser448, Asp203, Lys480, and Phe450. Furthermore, increases in postprandial blood glucose levels were significantly suppressed in the OPA-treated group compared with those in the streptozotocin-induced diabetic or normal mice. Additionally, the area under the curve was significantly reduced following OPA administration (907 versus 1034 mg h dL(-1)) in the diabetic mice, along with a delay in the absorption of dietary carbohydrates. Collectively, these results indicated that OPA is a potent inhibitor of α-glucosidase, and shows potential to be used as an anti-diabetic agent.
    No preview · Article · Aug 2014 · Food & Function
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    ABSTRACT: Hyperglycemia-induced oxidative stress accelerates endothelial cell dysfunctions, which cause various complications of diabetes. The protective effects of 6,6'-bieckol (BEK), one of phlorotannin compound purified from Ecklonia cava against high-glucose-induced oxidative stress was investigated using human umbilical vein endothelial cells (HUVECs), which is susceptible to oxidative stress. High glucose (30 mM) treatment induced HUVECs' cell death, but BEK, at concentration 10 or 50 μg/ml, significantly inhibited the high-glucose-induced cytotoxicity. Furthermore, treatment with BEK dose-dependently decreased thiobarbituric acid reactive substances (TBARS), intracellular reactive oxygen species (ROS) generation, and nitric oxide level increased by high glucose. In addition, high glucose levels induced the overexpressions of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and nuclear factor-kappa B (NF-κB) proteins in HUVECs, but BEK treatment reduced the overexpressions of these proteins. These findings indicate that BEK is a potential therapeutic agent that will prevent diabetic endothelial dysfunction and related complications.
    No preview · Article · Aug 2014 · Applied Biochemistry and Biotechnology
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    ABSTRACT: The antidiabetogenic and antioxidative effects of octaphlorethol A (OPA) isolated from the brown algae Ishige foliacea in streptozotocin (STZ)-induced diabetic mice were analyzed. STZ-induced diabetic mice showed a significant (p<0.05) increase in blood glucose and lipid peroxidation levels and a significant (p<0.05) decrease in the plasma insulin level and body weight, compared with controls. Diabetic mice also showed a significant (p<0.05) decrease in the activities of the antioxidant enzymes catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-px), compared with controls. Oral treatment with OPA (5 and 10 mg/kg) showed protective effects against all the biochemical parameters studied. OPA-treated mice exhibited suppression of apoptosis, and treatment with OPA was associated with an increase in antiapoptotic BclxL expression and a reduction in pro-apoptotic Bax and cleaved caspase-3 expressions. OPA has antidiabetogenic and antioxidative effects, and potential for use in therapies as both a natural functional food and a pharmaceutical agent.
    No preview · Article · Aug 2014 · Food science and biotechnology
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    ABSTRACT: The ability of water and ethanolic extracts isolated of Uncaria rhynchophylla (UR) to function as an anticancer agents was studied using HepG2 cells. The ethanolic UR extract was further fractionatedwith hexane, chloroform (CHCl3), ethyl acetate (EtOAc), n-butanol (n-BuOH), and water, and these fractions were subsequently investigated for anticancer activity. Among the fractions, the n-BuOH fraction induced apoptosis in a dose- and time-dependent manner, when determined by cell cycle analysis, Annexin V-FITC/PI double staining, and Hoechst 33342 staining. Moreover, the n-BuOH fraction induced apoptotic cell death by modulating the expression of caspase-7, caspase-8, and poly ADP ribose polymerase (PARP). These results indicated that the n-BuOH fraction from UR has strong anticancer activity in HepG2 cells and causes an upregulation of apoptotic proteins through the activation of PARP.
    No preview · Article · Jun 2014 · Biotechnology and Bioprocess Engineering
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    ABSTRACT: In this study, we investigated the anticancer activity of a newly isolated compound from Acer tegmentosum Maxim (ATM) in HepG2 cells. This compound was isolated by reverse-phase high-performance liquid chromatography (RP-HPLC) in a butanol-soluble fraction, which was shown to have the strongest anticancer activity. The isolated compound was identified as salidroside using multiple nuclear magnetic resonance (NMR) techniques, including 1H, 13C, correlated spectroscopy (COSY), heteronuclear single quantum coherence (HSQC), and heteronuclear multiple bond correlation (HMBC), as well as electrospray ionization mass spectroscopy (ESI/MS). The activity of salidroside was evaluated in HepG2 cells by analyzing cell proliferation, cell cycle distribution, Hoechst 33342 staining, and western blots of apoptotic regulatory proteins. The results show that salidroside, an anticancer compound from ATM, exhibits strong apoptotic activity in HepG2 cells. Therefore, ATM extracts could be used as chemotherapeutic agent to induce apoptosis in hepatoblastoma cells.
    No preview · Article · Jun 2014 · PROCESS BIOCHEMISTRY
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    ABSTRACT: In this study, Haliotis discus hannai (H. discus hannai) fermentation was attempted with Cordyceps militaris (C. militaris) mycelia using a solid culture. We tried to ferment H. discus hannai to determine the optimal conditions fermentation with regards to its anti-inflammatory effects. The extracts of H. discus hannai fermented with C. militaris mycelia (HFCM-5) showed higher nitric oxide inhibitory effects than H. discus hannai and C. militaris alone. HFCM-5 also decreased pro-inflammatory cytokines, TNF-α and IL-6 in a dose-dependent manner. HFCM-5 did not affect the MyD88-dependent pathway, but decreased phosphorylation of IRF3 and STAT1 which are involved in TRIF-dependent pathway. Taken together, our results suggest that HFCM-5 exerts its anti-inflammatory effects via TRIF signaling pathway and could potentially be used as a functional food in the regulation of inflammation.
    Full-text · Article · May 2014 · Fish & Shellfish Immunology
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    ABSTRACT: Chitin is a natural polysaccharide of major importance. This biopolymer is synthesized by an enormous number of living organisms; considering the amount of chitin produced annually in the world, it is the most abundant polymer after cellulose. The most important derivative of chitin is chitosan, obtained by partial deacetylation of chitin under alkaline conditions or by enzymatic hydrolysis. Chitin and chitosan are known to have important functional activities but poor solubility makes them difficult to use in food and biomedicinal applications. Chitooligosaccharides (COS) are the degraded products of chitosan or chitin prepared by enzymatic or chemical hydrolysis of chitosan. The greater solubility and low viscosity of COS have attracted the interest of many researchers to utilize COS and their derivatives for various biomedical applications. In light of the recent interest in the biomedical applications of chitin, chitosan, and their derivatives, this review focuses on the preparation and biological activities of chitin, chitosan, COS, and their derivatives.
    Full-text · Article · Mar 2014
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    ABSTRACT: Water and methanolic extracts of Ecklonia cava, a marine brown alga, were prepared by ultrasonic extraction (UE) and conventional extraction (CE) methods. The radical-scavenging activity and the inhibitory effects against hydrogen peroxide ()-induced DNA damage of the extracts were investigated. All extracts prepared by CE exhibited higher total polyphenolic content than that in the extracts prepared by UE. Extraction yield and total phenolic content increased as the UE time increased. The radical-scavenging activities increased as the UE time increased. All extracts prepared by CE exhibited higher 1,1-diphenyl-2-pricrylhydrazyl (DPPH) and hydroxyl radical-scavenging activities than did those prepared by UE. Extracts prepared by UE showed stronger scavenging activities on alkyl radical and than those prepared by CE did. Methanolic extract with UE 12 h (100MEU-12h) and methanolic extract with CE 24 h (100MEC-24h) were selected and evaluated by comet assay for their inhibitory effect against -induced DNA damage. 100MEU-12h showed slightly greater protective effect against -induced DNA damage than 100MEC-24h. Thus, UE can be effectively used as a seaweed extraction technique, and there is potential for scale-up of the extraction process.
    Full-text · Article · Dec 2013
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    ABSTRACT: Uncaria rhynchophylla (UR) is widely used as a traditional Chinese herbal medicine. However, there are few studies on antioxidant activity of UR extracts. The study was aimed at determining the antioxidant activity, the contents of polyphenol and flavonoid of UR extracts. Various assays were employed to evaluate the antioxidant property of water and ethanol extracts from the UR, compared to those of the other natural and synthetic antioxidants. UR extracts had high total phenolic contents in both the water (160 ± 2.32 mg GAE/g extracts) and ethanol extracts (190.2 ± 3.16 mg GAE/g extracts). In addition, total flavonoid contents were high in both the water extracts (154 ± 1.47 mg CE/g extracts) and ethanol extracts (184.2 ± 2.41 CE/g extracts). Specially, DPPH radical scavenging activity of ethanol extracts from UR were similar with vitamin C as a positive control. In addition, antioxidant capacity in ferric reducing antioxidant power (FRAP) were higher than that for BHT, which was used as a positive control. The antioxidant activity of extracts from UR showed stronger activity than those of vitamin C and α-tocopherol in ferric thiocyanate (FTC) and thiobarbituric acid (TBA) methods. The ethanol extracts of UR protected on H2O2-induced DNA damage. In addition, cytoprotective and anti-apoptotic effect of ethanol extracts from UR was also investigated in t-BHP-induced hepatotoxicity. Therefore, these results indicate that UR extracts have antioxidant properties through its ability to enhance the cell viability, mediation of production of ROS. The UR extracts could be suitable as an antioxidant in the food industry.
    No preview · Article · Dec 2013 · Biotechnology and Bioprocess Engineering