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Kim H, Jeong EJ, Park C, Lee JS, Kim WJ, Yu KW, Suh HJ, Ahn Y, Moon SK. Modulation of gut microbiota ecosystem by a glucan-rich snail mucin heteropolysaccharide attenuates loperamide-induced constipation. Int J Biol Macromol 2023; 253:126560. [PMID: 37640190 DOI: 10.1016/j.ijbiomac.2023.126560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 07/10/2023] [Accepted: 08/25/2023] [Indexed: 08/31/2023]
Abstract
The present study aimed to investigate the effect of oral administration of snail-derived mucin extract (SM) on ameliorating constipation symptoms of loperamide-induced constipated rats (n = 6). The analytical results indicated that SM mainly contains a glucan-rich snail mucin heteropolysaccharide with high molecular weights (108.5-267.9 kDa), comprising primarily of glucose (64.9 %) and galactose (22.4 %) with some deoxyhexoses (5.0 %) and hexosamines (4.9 %). Daily SM administration at doses of 10-40 mg/kg/day to the loperamide-induced constipated rats significantly (p < 0.05) ameliorated the deterioration in fecal parameters, such as numbers and weight of feces, fecal water contents, and gastrointestinal transit ratio. The histomorphometric results showed that the loperamide-induced decreases in the thickness of mucosal and muscularis mucosae layers as well as the distribution of mucin and c-KIT-positive areas were significantly (p < 0.05) improved via SM consumption at all doses tested. SM administration at all doses significantly increased the expression of genes encoding tryptophan hydroxylases (TPH1 and TPH2; p < 0.05), tight junction molecules (OCLN, CLDN1, and TJP1; p < 0.05), and mucin (MUC2 and MUC4; p < 0.05), but significantly decreased the aquaporin-encoding genes (AQP3 and AQP8; p < 0.05). Gut microbial community analysis indicated that SM administration could modulate loperamide-induced dysbiosis by increasing the phyla Actinobacteria (11.72-12.64 % at 10-40 mg/kg doses; p < 0.05) and Firmicutes (79.33 % and 74.24 % at 20 and 40 mg/kg doses; p < 0.05) and decreasing the phyla Bacteroidetes (5.98-12.47 % at 10-40 mg/kg doses; p < 0.05) and Verrucomicrobia (2.21 % and 2.78 % at 20 and 40 mg/kg doses; p < 0.05), suggesting that SM administration is effective in ameliorating constipation by controlling gut microbial communities. These findings can be utilized as fundamental data for developing novel functional materials using SM to prevent or treat constipation.
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Affiliation(s)
- Hoon Kim
- Department of Food and Nutrition, Chung-Ang University, 4726 Seodong-daero, Daedeok-myeon, Anseong 17546, South Korea
| | - Eun-Jin Jeong
- Department of Integrated Biomedical and Life Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, South Korea; BK21 FOUR R&E Center for Learning Health Systems, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, South Korea
| | - Chunwoong Park
- Department of Integrated Biomedical and Life Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, South Korea; BK21 FOUR R&E Center for Learning Health Systems, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, South Korea
| | - Jeong-Seok Lee
- Age at Labs Inc., 55, Digital-ro 32-gil, Guro-gu, Seoul 08379, South Korea
| | - Woo Jung Kim
- Biocenter, Gyeonggido Business and Science Accelerator, Suwon 16229, South Korea
| | - Kwang-Won Yu
- Major in Food & Nutrition, Korea National University of Transportation, 61 Daehak-ro, Jeungpyeong 27909, South Korea
| | - Hyung Joo Suh
- Department of Integrated Biomedical and Life Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, South Korea
| | - Yejin Ahn
- Department of Integrated Biomedical and Life Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, South Korea.
| | - Sung-Kwon Moon
- Department of Food and Nutrition, Chung-Ang University, 4726 Seodong-daero, Daedeok-myeon, Anseong 17546, South Korea.
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Suh MG, Shin HY, Jeong EJ, Kim G, Jeong SB, Ha EJ, Choi SY, Moon SK, Shin KS, Yu KW, Suh HJ, Kim H. Identification of galacturonic acid-rich polysaccharide with intestinal immune system modulating activity via Peyer's patch from postbiotics of Phellinus linteus mycelial submerged culture. Int J Biol Macromol 2023; 234:123685. [PMID: 36796554 DOI: 10.1016/j.ijbiomac.2023.123685] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 01/05/2023] [Accepted: 02/10/2023] [Indexed: 02/17/2023]
Abstract
Interests in the development and exploration of industrial applications of medicinal mushrooms as postbiotics have lately increased. We recently reported the potential use of Phellinus linteus mycelial-containing whole culture extract (PLME) prepared by submerged cultivation as a postbiotic that promotes immune system activation. Here, we aimed to isolate and structurally elucidate the active ingredients in PLME by activity-guided fractionation. The intestinal immunostimulatory activity was evaluated by bone marrow (BM) cell proliferation activity and related cytokine production in C3H-HeN mouse-derived Peyer's patch (PP) cells treated with polysaccharide fractions. The initially crude polysaccharide (PLME-CP) of PLME prepared using ethanol precipitation was further fractionated into four fractions (PLME-CP-0 to -III) by anion-exchange column chromatography. BM cell proliferation and cytokine production of PLME-CP-III were significantly improved compared to those of PLME-CP. PLME-CP-III was then fractionated into PLME-CP-III-1 and PLME-CP-III-2 by gel filtration chromatography. Based on the molecular weight distribution, monosaccharide, and glycosyl linkage analyses, PLME-CP-III-1 was revealed as a novel galacturonic acid-rich acidic polysaccharide and further shown to play an important role in facilitating PP-mediated intestinal immunostimulatory activity. This is the first study demonstrating the structural characteristics of a novel intestinal immune system modulating acidic polysaccharide from P. linteus mycelium-containing whole culture broth postbiotics.
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Affiliation(s)
- Min Geun Suh
- Department of Integrated Biomedical and Life Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, South Korea; R&D Center Neo Cremar Cooperation Limited, 211 Jungdae-ro, Songpa-gu, Seoul 05702, South Korea
| | - Hyun Young Shin
- Department of Integrated Biomedical and Life Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, South Korea; BK21FOUR R&E Center for Learning Health Systems, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, South Korea
| | - Eun-Jin Jeong
- Department of Integrated Biomedical and Life Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, South Korea; BK21FOUR R&E Center for Learning Health Systems, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, South Korea
| | - Gaeuleh Kim
- Major in Food & Nutrition, Korea National University of Transportation, 61 Daehak-ro, Jeungpyeong 27909, South Korea
| | - Se Bin Jeong
- Major in Food & Nutrition, Korea National University of Transportation, 61 Daehak-ro, Jeungpyeong 27909, South Korea
| | - Eun Ji Ha
- Major in Food & Nutrition, Korea National University of Transportation, 61 Daehak-ro, Jeungpyeong 27909, South Korea
| | - Sang-Yong Choi
- R&D Center Neo Cremar Cooperation Limited, 211 Jungdae-ro, Songpa-gu, Seoul 05702, South Korea
| | - Sung-Kwon Moon
- Department of Food and Nutrition, Chung-Ang University, 4726 Seodong-daero, Daedeok-myeon, Anseong 17546, South Korea
| | - Kwang-Soon Shin
- Department of Food and Biotechnology, Kyonggi University, 154-42 Gwanggyosan-ro, Yeongtong-gu, Suwon 16227, South Korea
| | - Kwang-Won Yu
- Major in Food & Nutrition, Korea National University of Transportation, 61 Daehak-ro, Jeungpyeong 27909, South Korea
| | - Hyung-Joo Suh
- Department of Integrated Biomedical and Life Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, South Korea; BK21FOUR R&E Center for Learning Health Systems, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, South Korea
| | - Hoon Kim
- Department of Food and Nutrition, Chung-Ang University, 4726 Seodong-daero, Daedeok-myeon, Anseong 17546, South Korea.
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Kim H, Shin HY, Jeong EJ, Lee HD, Hwang KC, Yu KW, Lee S, Lee S. Antioxidant and Anti-Inflammatory Activities of Sargassum macrocarpum Extracts. Antioxidants (Basel) 2022; 11:antiox11122483. [PMID: 36552691 PMCID: PMC9774442 DOI: 10.3390/antiox11122483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 12/08/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022] Open
Abstract
Oxidative stress and the inflammatory response are known to be the most important pathological factors for aging skin cells. Therefore, substances that protect skin cells from oxidative stress and inflammatory reactions of the skin have potential as functional ingredients for skin care. In the present study, we investigated the potential of Sargassum macrocarpum as an anti-inflammatory candidate for inflammatory skin disease. Antioxidant and anti-inflammatory activities are desirable properties in such functional materials. The total polyphenol content as well as antioxidant and anti-inflammatory activities were evaluated in hot-water (HES) and ethanol (EES) extracts of S. macrocarpum. The polyphenol content was higher in the HES (HES: 115.9 ± 15.3 mg GA/g, EES: 3.9 ± 0.5 mg GA/g), and the HES also had ABTS (HES: IC50 1.0 ± 0.0 mg/mL, EES: IC50 16.09 ± 0.7 mg/mL) and DPPH (HES: IC50 6.50 ± 0.3 mg/mL, EES: IC50 35.3 ± 3.1 mg/mL) radical scavenging capacities as well as FRAP activity (HES: IC50 18.8 ± 0.4 mg/mL, EES: IC50 n.d.). Compared with the EES at the equivalent concentration range (1.25-20 μg/mL), the HES exerted a more potent inhibitory activity on LPS-stimulated nitric oxide (10.3-43.1%), IL-6 (15.7-45.0%), and TNF-α (14.1-20.8%) in RAW 264.7 macrophage cells in addition to TNF-α and IFN-γ-facilitated IL-6 (10.9-84.1%) and IL-8 (7.7-73.2%) in HaCaT keratinocytes. These results suggested that water-soluble materials might be deeply involved in the antioxidant and anti-inflammatory activity in S. macrocarpum. General composition analysis indicated that the HES contains more carbohydrates and polyphenols than the EES, and the monosaccharide composition analysis suggested that fucose-containing sulfated polysaccharide and β-glucan might be potent anti-inflammatory candidates in the HES. The present study presents important preliminary results and a valuable strategy for developing novel anti-skin dermatitis candidates using a hot-water extract of S. macrocarpum.
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Affiliation(s)
- Hoon Kim
- Department of Food Science and Nutrition, Chung-Ang University, Anseong 17546, Republic of Korea
| | - Hyun Young Shin
- Department of Integrated Biomedical and Life Science, Korea University, Seoul 02841, Republic of Korea
| | - Eun-Jin Jeong
- Department of Integrated Biomedical and Life Science, Korea University, Seoul 02841, Republic of Korea
- Department of Food and Nutrition, Korea National University of Transportation, Jeungpyeong 27909, Republic of Korea
| | - Hak-Dong Lee
- Department of Plant Science and Technology, Chung-Ang University, Anseong 17546, Republic of Korea
| | - Ki Cheol Hwang
- Venture Research Center, Rafarophe Co., Cheongju 28164, Republic of Korea
| | - Kwang-Won Yu
- Department of Food and Nutrition, Korea National University of Transportation, Jeungpyeong 27909, Republic of Korea
| | - Sullim Lee
- Department of Life Science, Gachon University, Seongnam 13120, Republic of Korea
- Correspondence: (S.L.); (S.L.)
| | - Sanghyun Lee
- Department of Plant Science and Technology, Chung-Ang University, Anseong 17546, Republic of Korea
- Natural Product Institute of Science and Technology, Anseong 17546, Republic of Korea
- Correspondence: (S.L.); (S.L.)
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Han K, Ahn Y, Hong KB, Suh HJ, Yu KW, Kim H. Ameliorating the efficacy of galacto-oligosaccharides on ovalumin-induced allergic dermatitis symptoms in Balb/c mice by regulating Th2 immune response and the ecosystem of gut microbiota. Food Funct 2022; 13:6271-6281. [PMID: 35604005 DOI: 10.1039/d2fo00157h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this study, we evaluated the effect of oral administration of galacto-oligosaccharide (GOS), famous biological molecules that are comprised of galactose and lactose, on ovalbumin (OVA)-induced allergic dermatitis. OVA-induced mice were divided into the OVA-administered group (OVA-C), promethazine hydrochloride-administered group (PC), and 100 and 200 mg kg-1 GOS-administered groups (GL and GH, respectively). GOS administration significantly improved epidermal thickness and decreased CD4+ cell numbers. The concentrations of IgE, OVA-specific IgE, and inflammatory cytokines (IL-4, IL-5, and INF-γ) in GH group mice were significantly lower than those in OVA-C group mice. Firmicutes and Bacteroidetes were identified as the major phyla in the intestinal microbiota in mice, and the relative abundance of Deferribacteres was significantly lower in the GH group than in the OVA-C group. Deferribacteraceae and Mucispirillum species were significantly lower in the GH group than in the OVA-C group. The relative abundance of Muribaculum species was significantly lower, but those of Lachnospira and Lactococcus species were significantly higher in the GH group than in the OVA-C group. Our results suggest that the alleviation effect of GOS on allergic dermatitis induced by OVA sensitization was achieved by regulating hypersensitive immune responses by improving the intestinal microbial ecosystem.
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Affiliation(s)
- Kisoo Han
- Department of Integrated Biomedical and Life Science, Graduate School, Korea University, Seoul 02841, Republic of Korea.
| | - Yejin Ahn
- Department of Integrated Biomedical and Life Science, Graduate School, Korea University, Seoul 02841, Republic of Korea.
| | - Ki-Bae Hong
- Department of Food Science and Nutrition, Jeju National University, Jeju 63243, Republic of Korea.
| | - Hyung Joo Suh
- Department of Integrated Biomedical and Life Science, Graduate School, Korea University, Seoul 02841, Republic of Korea. .,Transdisciplinary Major in Learning Health Systems, Graduate School, Korea University, Republic of Korea
| | - Kwang-Won Yu
- Division of Food and Nutrition, Korea National University of Transportation, Republic of Korea.
| | - Hoon Kim
- Department of Food and Nutrition, Chung-Ang University, Anseong 17546, Republic of Korea.
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Jo K, Kim S, Yu KW, Chung YB, Kim WJ, Suh HJ, Kim H. Changes in the component sugar and immunostimulating activity of polysaccharides isolated from Dendrobium officinale in the pretreatments. J Sci Food Agric 2022; 102:3021-3028. [PMID: 34775614 DOI: 10.1002/jsfa.11642] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 08/29/2021] [Accepted: 11/14/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND To isolate polysaccharides with enhanced immunostimulatory activity from Dendrobium officinale, which is used as a herbal medicine in China and Southeast Asia, D. officinale (DO) was pretreated with organic solvents (DOOS) or puffing at 7.5 and 9.0 kgf (7.5DO and 9DO). Hot-water extracts (DOOS-HW, 7.5DO-HW and 9DO-HW) were prepared from each pretreated DO, along with non-pretreated DO, and crude polysaccharides (DO-CP, DOOS-CP, 7.5DO-CP and 9DO-CP) were fractionated from each hot-water extract using ethanol (five volumes). RESULTS When their immunostimulatory activities were compared by macrophage stimulation and intestinal immune system modulation via Peyer's patches, DOOS-CP showed more potent activity than DO-CP. However, crude polysaccharides fractionated from puffed DO showed significantly lower activity than non-puffed DO and DOOS. The most active polysaccharide contained 95% or more neutral sugar, and the composition ratio of mannose and glucose was 3.0, whereas the lowest polysaccharide content was 2.0 or less. In addition, DOOS-CP was a somewhat refined fraction containing a major peak, representing a molecular weight of 250 kDa, despite being a crude polysaccharide. CONCLUSION These results suggest that pretreatment of D. officinale with organic solvents may enhance the immunostimulatory activity of polysaccharides and affect the mannose/glucose ratio of polysaccharides, which plays an important role in immunostimulation. © 2021 Society of Chemical Industry.
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Affiliation(s)
- Kyungae Jo
- Department of Integrated Biomedical and Life Science, Graduate School, Korea University, Seoul, Republic of Korea
| | - Singeun Kim
- Department of Integrated Biomedical and Life Science, Graduate School, Korea University, Seoul, Republic of Korea
| | - Kwang-Won Yu
- Department of Food and Nutrition, Korea National University of Transportation, Chungbuk, Republic of Korea
| | - Young Bae Chung
- Department of Integrated Biomedical and Life Science, Graduate School, Korea University, Seoul, Republic of Korea
- Research and Development Division, World Institute of Kimchi, Gwangju, Republic of Korea
| | - Woo Jung Kim
- Biocenter, Gyeonggido Business and Science Accelerator, Suwon, Republic of Korea
| | - Hyung Joo Suh
- Department of Integrated Biomedical and Life Science, Graduate School, Korea University, Seoul, Republic of Korea
| | - Hoon Kim
- College of Biotechnology and Natural Resources, Chung-Ang University, Anseong, Republic of Korea
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Bae YJ, Yu KW, Lee KH, Jang KI. Association of the Healthy Eating Index with Metabolic Abnormalities among Middle-Aged Adults Living in Single-Person Households in Korea. Nutrients 2021; 13:3937. [PMID: 34836192 PMCID: PMC8624069 DOI: 10.3390/nu13113937] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 11/01/2021] [Accepted: 11/02/2021] [Indexed: 01/07/2023] Open
Abstract
This study aimed to analyze the association between the dietary lifestyles and health outcomes among middle-aged (40-64 years old) and elderly (65 years old and older) individuals living alone using the Korean Healthy Eating Index (KHEI). The study was conducted with 1442 participants (475 men and 967 women) aged 40 years and older living in single-person households using the Korea National Health and Nutrition Examination Survey from 2016 to 2018. The KHEI scores were calculated based on the 24-h recall data of dietary intake. Among women living alone, the total KHEI score of the participants aged 40-64 years was 65.92, which was significantly lower than the 70.66 of those aged 65 years and older (p = 0.0152). In addition, the total score in the adequacy domain was significantly lower among the 40~64-year-old group than those aged 65 years and older (p = 0.0011). Among the elderly in single-person households, the odds of diabetes in the T1 group were 2.08 times higher than those in the T3 group according to the KHEI (95% confidence interval: 1.36-3.17). The results of this study are expected to be used as baseline data to establish nutrition, home meal replacement utilization, and health policies for the elderly living alone.
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Affiliation(s)
- Yun-Jung Bae
- Major in Food and Nutrition, Division of Food Science and Biotechnology, Korea National University of Transportation, Jeungpyeong 27909, Korea; (K.-W.Y.); (K.-H.L.)
| | - Kwang-Won Yu
- Major in Food and Nutrition, Division of Food Science and Biotechnology, Korea National University of Transportation, Jeungpyeong 27909, Korea; (K.-W.Y.); (K.-H.L.)
| | - Kyung-Haeng Lee
- Major in Food and Nutrition, Division of Food Science and Biotechnology, Korea National University of Transportation, Jeungpyeong 27909, Korea; (K.-W.Y.); (K.-H.L.)
| | - Keum-Il Jang
- Department of Food Science and Biotechnology, Chungbuk National University, Cheongju 28644, Korea;
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Kim S, Jo K, Byun BS, Han SH, Yu KW, Suh HJ, Hong KB. Chemical and biological properties of puffed Dendrobium officinale extracts: Evaluation of antioxidant and anti-fatigue activities. J Funct Foods 2020. [DOI: 10.1016/j.jff.2020.104144] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
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Park HR, Hwang D, Suh HJ, Yu KW, Kim TY, Shin KS. Antitumor and antimetastatic activities of rhamnogalacturonan-II-type polysaccharide isolated from mature leaves of green tea via activation of macrophages and natural killer cells. Int J Biol Macromol 2017; 99:179-186. [PMID: 28223130 DOI: 10.1016/j.ijbiomac.2017.02.043] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 01/11/2017] [Accepted: 02/09/2017] [Indexed: 01/04/2023]
Abstract
To investigate the antitumor and antimetastatic polysaccharide from the mature leaves of green tea, GTE-II was purified using size exclusion chromatography. GTE-II consisted of 15 different sugars including rarely observed sugars such as 2-O-methyl-fucose, 2-O-methyl-xylose, apiose, aceric acid, 3-deoxy-d-manno-2-octulosonic acid, and 3-deoxy-d-lyxo-2-heptulosaric acid, which were characteristics of pectic polysaccharide rhamnogalacturonan-II. Treatment of peritoneal macrophages with GTE-II not only increased interleukin (IL)-6 and IL-12 production, but also had significantly increased tumoricidal activity against Yac-1 tumor cells than those obtained from untreated mice. In an assay of natural killer (NK) cell activity, intravenous administration of GTE-II significantly stimulated NK cytotoxicity against Yac-1 tumor cells. Furthermore, the depletion of NK cells by injection of rabbit anti-asialo GM1 serum eliminated the inhibitory effect of GTE-II on B16BL6 melanoma cells. These data suggest that GTE-II inhibits tumor metastasis, and its antitumor effect is associated with activation of macrophages and NK cells.
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Affiliation(s)
- Hye-Ryung Park
- Department of Food Science and Biotechnology, Kyonggi University, Gyeonggi, South Korea; Department of Integrated Biomedical and Life Science, Korea University, Seoul, South Korea
| | - Dahyun Hwang
- Department of Biomedical Laboratory Science, College of Life and Health Sciences, Hoseo University, Asan, South Korea
| | - Hyung-Joo Suh
- Department of Integrated Biomedical and Life Science, Korea University, Seoul, South Korea
| | - Kwang-Won Yu
- Department of Food and Nutrition, Korea National University of Transportation, Chungbuk, South Korea
| | | | - Kwang-Soon Shin
- Department of Food Science and Biotechnology, Kyonggi University, Gyeonggi, South Korea.
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Kim H, Suh HJ, Kwon KH, Hwang JH, Yu KW. Immunostimulation activity of a polysaccharide from fermented ginseng with Hericium erinaceum mycelia in solid-state culture. Food Sci Biotechnol 2016; 25:311-318. [PMID: 30263272 DOI: 10.1007/s10068-016-0044-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 10/26/2015] [Accepted: 10/29/2015] [Indexed: 11/30/2022] Open
Abstract
Korean fresh ginseng was cultured with Hericium erinaceum mycelia (HE) in solid-state culture (SSC) to enhance the immunomodulation activity. Hot-water extracts (FG-HE-HW) of H. erinaceum-fermented ginseng (FG-HE) fractionated into a crude polysaccharide (FG-HE-CP) showed higher mitogenic, macrophage stimulation, and intestinal immune system modulation activities (1.52, 1.63, and 1.35x relative to a saline control at 100 μg/mL, respectively) than the crude polysaccharide from non-fermented ginseng (NG-CP; 1.35, 1.50, and 1.18x) and H. erinaceum mycelia alone (HE-CP; 1.26, 1.46, and 1.27x). After FG-HE-CP was further fractionated on a DEAE-Sepharose CL-6B column, the polysaccharide fraction (FG-HE-CP-III) exhibited larger activity increases than any subfraction from NG-CP or HE-CP. FG-HE-CP-III mainly consisted of Ara, Gal, Glc, and GalA (molar ratios of 0.45:1.00: 0.51:0.73). NaIO4 oxidation decreased the activities of FG-HE-CP-III (51.0-76.9%). The polysaccharide from H. erinaceum-fermented ginseng using SSC plays an important role for enhancement of immunomodulation activities of fresh ginseng.
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Affiliation(s)
- Hoon Kim
- 1Department of Integrated Biomedical and Life Science, Korea University, Seoul, 02841 Korea
| | - Hyung-Joo Suh
- 1Department of Integrated Biomedical and Life Science, Korea University, Seoul, 02841 Korea
| | - Ki-Han Kwon
- 2Department of Food and Nutrition, Gwangju University, Gwangju, 61743 Korea
| | - Jong-Hyun Hwang
- 3Department of Food and Nutrition, Korea National University of Transportation, Jeungpyeong-gun, Chungbuk, 27909 Korea
| | - Kwang-Won Yu
- 3Department of Food and Nutrition, Korea National University of Transportation, Jeungpyeong-gun, Chungbuk, 27909 Korea
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Ju HM, Yu KW, Cho SD, Cheong SH, Kwon KH. Anti-cancer effects of traditional Korean wild vegetables in complementary and alternative medicine. Complement Ther Med 2016; 24:47-54. [DOI: 10.1016/j.ctim.2015.11.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 07/18/2015] [Accepted: 11/26/2015] [Indexed: 11/16/2022] Open
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Baik JH, Shin KS, Park Y, Yu KW, Suh HJ, Choi HS. Biotransformation of catechin and extraction of active polysaccharide from green tea leaves via simultaneous treatment with tannase and pectinase. J Sci Food Agric 2015; 95:2337-2344. [PMID: 25307474 DOI: 10.1002/jsfa.6955] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 09/23/2014] [Accepted: 10/08/2014] [Indexed: 06/04/2023]
Abstract
BACKGROUND Green tea is a dietary source of bioactive compounds for human health. Enzymatic treatments induce the bioconversion of bioactive components, which can improve biological activities. In this study, we investigated the effect of simultaneous treatment with tannase and Rapidase on biotransformation of catechins and extraction of polysaccharide from green tea extract (GTE). RESULTS Tannase and pectinase treatments induced the biotransformation of catechins and altered tea polysaccharide () content. The addition of GTE to the enzyme reaction resulted in a significant increase in degallated catechins, including gallic acid, a product of the tannase reaction (314.5-4076.0 µg mL(-1)) and a reduction in epigallocatechin gallate (EGCG). Biotransformation of catechins improved the radical scavenging activity of GTE. Pectinase treatment led to change of TPS composition in GTE by hydrolyzing polysaccharides. In addition, pectinase-driven hydrolysis in polysaccharides significantly increased TPS-induced Interleukin 6 (IL-6) production in macrophages. In particular, treatment of Rapidase (TPS-Ra) led to the highest IL-6 production among TPS samples, similar to treatment of highly purified pectinase (TPS-GTE), a positive control. CONCLUSION Simultaneous processing with tannase and Rapidase can be an efficient method for the extraction of bioactive polysaccharides and biotransformation of catechins with enhanced radical scavenging activity from green tea.
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Affiliation(s)
| | - Kwang-Soon Shin
- Department of Food Science and Biotechnology, Kyonggi University, Suwon, 443-760, Republic of Korea
| | - Yooheon Park
- Department of Food and Nutrition, Korea University, Seoul, 136-703, Republic of Korea
| | - Kwang-Won Yu
- Department of Food and Nutrition, Korea National University of Transportation, Jeungpyeong, 368-701, Republic of Korea
| | - Hyung Joo Suh
- Department of Food and Nutrition, Korea University, Seoul, 136-703, Republic of Korea
| | - Hyeon-Son Choi
- Department of Food Science and Technology, Seoul Women's University, Seoul, 139-774, Republic of Korea
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Hong YH, Jung EY, Shin KS, Yu KW, Chang UJ, Suh HJ. Tannase-converted green tea catechins and their anti-wrinkle activity in humans. J Cosmet Dermatol 2014; 12:137-43. [PMID: 23725307 DOI: 10.1111/jocd.12038] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/15/2013] [Indexed: 01/09/2023]
Abstract
BACKGROUND This study was performed to investigate the anti-wrinkle effects of topical applications of green tea extract with high antioxidant activity by tannase treatment. Increases in gallic acid (GA), (-)-epigallocatechin (EGC), and (-)-epicatechin (EC) were observed in the green tea extract after tannase treatment. OBJECTIVES This study was performed to investigate the anti-wrinkle effects of topical applications of green tea extract exhibiting high antioxidant activity after tannase treatment. METHODS Subjects, randomly divided into two groups, received the application of either tannase-converted green tea extract (TGE) or normal green tea extract (NGE) on their crow's feet for 8 weeks. The anti-wrinkle effects were evaluated with two methods: (i) self-assessment; and (ii) average roughness of skin surface (R(a), R(z), and R(t) value) using skin replica and Skin-Visiometer SV 600. RESULTS The scavenging abilities of TGE against radicals were significantly higher compared to NGE. The evaluation of skin wrinkle index values after 8 weeks of treatment showed that reductions of R(a), R(z), and R(t) values in the TGE group were significantly greater than in the NGE group, which indicated that tannase treatment improved the anti-wrinkle effects of green tea extract. According to the overall ratings for wrinkle treatment by applying the formulations, most of the TGE group (63.60%) reported marked or moderate improvement in wrinkles compared with only 36.30% of the NGE group. CONCLUSION Tannase treatment can improve the antioxidant activity of green tea extract, conferring anti-wrinkle activities. These results suggest that TGE may have beneficial properties as an anti-wrinkle agent.
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Affiliation(s)
- Yang-Hee Hong
- Department of Food and Nutrition, Korea University, Seoul, Korea
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Kim H, Suh HJ, Kang CM, Lee KH, Hwang JH, Yu KW. Immunological Activity of Ginseng Is Enhanced by Solid-State Culture with Ganoderma lucidum Mycelium. J Med Food 2014; 17:150-60. [DOI: 10.1089/jmf.2013.3063] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Affiliation(s)
- Hoon Kim
- Department of Food and Nutrition, Korea University, Seoul, Korea
| | - Hyung Joo Suh
- Department of Food and Nutrition, Korea University, Seoul, Korea
| | - Choong-Min Kang
- Department of Biological Sciences, California State University, Stanislaus, California, USA
| | - Kyung-Haeng Lee
- Department of Food and Nutrition, Korea National University of Transportation, Chungbuk, Korea
| | - Jong-Hyun Hwang
- Department of Food and Nutrition, Korea National University of Transportation, Chungbuk, Korea
| | - Kwang-Won Yu
- Department of Food and Nutrition, Korea National University of Transportation, Chungbuk, Korea
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Ou SM, Lee SY, Chen JY, Cheng HW, Wei TH, Yu KW, Lin WM, King KL, Yang WC, Ng YY. First identification of Gordonia sputi in a continuous ambulatory peritoneal dialysis patient with Peritonitis. Perit Dial Int 2013; 33:107-8. [PMID: 23349205 DOI: 10.3747/pdi.2012.00030] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Yoon TJ, Lee SJ, Kim EY, Cho EH, Kang TB, Yu KW, Suh HJ. Inhibitory effect of chaga mushroom extract on compound 48/80-induced anaphylactic shock and IgE production in mice. Int Immunopharmacol 2013; 15:666-70. [DOI: 10.1016/j.intimp.2013.03.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 03/03/2013] [Accepted: 03/15/2013] [Indexed: 12/13/2022]
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Kim JH, Lee HJ, Park Y, Ra KS, Shin KS, Yu KW, Suh HJ. Mucilage removal from cactus cladodes (Opuntia humifusa Raf.) by enzymatic treatment to improve extraction efficiency and radical scavenging activity. Lebensm Wiss Technol 2013. [DOI: 10.1016/j.lwt.2012.10.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Yu KW, Suh HJ, Hwang JH. Fermentative Properties and Immunomodulating Activity of Low-sodium Kimchi Supplemented with Acanthopanax senticosus and Glycyrrhizae uralensis Extracts. ACTA ACUST UNITED AC 2012. [DOI: 10.9799/ksfan.2012.25.4.878] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Yip CW, Chan MY, Cheung WF, Yu KW, Tang HS, Kam KM. Random blinded rechecking of sputum acid-fast bacilli smear using fluorescence microscopy: 8 years' experience. Int J Tuberc Lung Dis 2012; 16:398-401. [PMID: 22640454 DOI: 10.5588/ijtld.11.0330] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The Hong Kong TB Reference Laboratory is a high volume laboratory examining around 400 sputum acid-fast bacilli smears daily using fluorescence microscopy (FM). OBJECTIVE To assess the effectiveness of blinded rechecking applied to FM in a high-throughput laboratory. METHOD From 2003, 2.5% (5% in 2003 and 2004) of all smears were randomly selected, relabelled and assigned to each technician (rechecker) in turn. These smears were restained and re-examined. Discordance between initial screener and rechecker was resolved by a controller. RESULTS From 2003 to 2010, low false-negative (LFN) errors (0.10-0.27%) were within the critical values, at 85% (1 year) and 90% (7 years) sensitivity. However, LFN error (0.28-0.62%) among recheckers was prominent. There were also low false-positive (LFP) cases (0.13-0.75%), but subsequent cultures showed these to be mycobacteria culture-positive. This relatively poor performance among the recheckers might be due to background fluorescence increase after restaining and/or inefficiency of the rechecking procedure. CONCLUSION In a high-throughput laboratory, blind rechecking is a good means of quality assurance. To minimise false LFP, problems due to restaining should be resolved before blinded rechecking can be generally applied in the field for FM where mycobacterial cultures are not routinely performed.
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Affiliation(s)
- C W Yip
- Tuberculosis Reference Laboratory, Public Health Laboratory Centre, Centre for Health Protection, Department of Health, Hong Kong SAR, China
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Bae SH, Choi JW, Ra KS, Yu KW, Shin KS, Park SS, Suh HJ. Anti-complementary activity of enzyme-treated traditional Korean rice wine (Makgeolli) hydrolysates. J Sci Food Agric 2012; 92:1765-1770. [PMID: 22173736 DOI: 10.1002/jsfa.5543] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Revised: 10/25/2011] [Accepted: 11/10/2011] [Indexed: 05/31/2023]
Abstract
BACKGROUND Makgeolli brewed from rice contains about 150 g kg(-1) alcohol and has a fragrance as well as an acidic and sweet taste. During the brewing process, by-products such as rice bran and brewery cake are produced. At the end of fermentation the matured mash is transferred to a filter cloth and the Makgeolli is squeezed out from the cake, leaving the lees of the mash. These by-products have continued to increase every year, resulting in an ecological problem. It is therefore important to develop new uses for them. The objective of this study was to use the by-products from the brewing of Makgeolli as a valuable functional food or nutraceutical. RESULTS The anti-complementary activities of crude polysaccharides isolated from Cytolase hydrolysates of Makgeolli lees at concentrations of 1000 and 500 µg mL(-1) were 84.15 and 78.70% respectively. The activity of polysaccharide krestin (PSK) was 60.00% at 1000 µg mL(-1). The active polysaccharide obtained with Cytolase comprised mainly glucose and mannose (molar ratio 1.00:0.62). CONCLUSION Glucose- and mannose-rich crude polysaccharides were isolated from the Cytolase hydrolysate of Makgeolli lees. The polysaccharides retain anti-complementary activity to enhance the immune system as a functional food or nutraceutical.
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Affiliation(s)
- Song Hwan Bae
- Department of Food and Biotechnology, Hankyong National University Anseong, Anseong 456-749, South Korea
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Hong YH, Jung EY, Shin KS, Kim TY, Yu KW, Chang UJ, Suh HJ. Photoprotective effects of a formulation containing tannase-converted green tea extract against UVB-induced oxidative stress in hairless mice. Appl Biochem Biotechnol 2011; 166:165-75. [PMID: 22068688 DOI: 10.1007/s12010-011-9413-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Accepted: 10/18/2011] [Indexed: 01/21/2023]
Abstract
Ultraviolet B (UVB) irradiation may induce the acceleration of skin aging. The purpose of this study was to develop an effective formulation containing tannase-converted green tea extract (FTGE) to inhibit UVB-induced oxidative damage. Significant (p<0.05) prevention of the reduced form of glutathione (GSH) depletion was observed in mice treated with FTGE. The hydrogen peroxide levels of mice treated with FTGE were similar to those of UVB non-irradiated mice. No significant difference was observed between No UVB control and FTGE mice. Also, mice treated with FTGE had significant (p<0.05) decreases in thiobarbituric acid-reactive substance levels by lipid peroxidation compared with No UVB control mice. Our data suggest that this formulation may be effective in protecting skin from UVB photodamage.
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Affiliation(s)
- Yang-Hee Hong
- Research Institute of Health and Sciences, Korea University, Seoul, Republic of Korea
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Kim H, Jeong JH, Shin JY, Kim DG, Yu KW. Immunomodulatory and Anti-Inflammatory Activity of Mulberry (Morus alba) Leaves Fermented with Hericium erinaceum Mycelium by Solid-State Culture. ACTA ACUST UNITED AC 2011. [DOI: 10.3746/jkfn.2011.40.9.1333] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Kim BG, Shin KS, Yoon TJ, Yu KW, Ra KS, Kim JM, Kim SY, Suh HJ. Fermentation of Korean Red Ginseng by Lactobacillus plantarum M-2 and Its Immunological Activities. Appl Biochem Biotechnol 2011; 165:1107-19. [DOI: 10.1007/s12010-011-9328-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Accepted: 07/13/2011] [Indexed: 11/27/2022]
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Kim DJ, Oh SK, Chun AR, Yoon MR, Hong HC, Choi IS, Lee JS, Yu KW, Kim YK. Evaluation of Biological Activities of Rice Husk Extracts. Prev Nutr Food Sci 2011. [DOI: 10.3746/jfn.2011.16.2.179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Kim DJ, Oh SK, Yoon MR, Chun AR, Choi IS, Lee DH, Lee JS, Yu KW, Kim YK. The Change in Biological Activities of Brown Rice and Germinated Brown Rice. ACTA ACUST UNITED AC 2011. [DOI: 10.3746/jkfn.2011.40.6.781] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Ling CW, Zheng MJ, Yu KW. Tunable hybridization in metal nanoshell chains. J Phys Condens Matter 2011; 23:105304. [PMID: 21339586 DOI: 10.1088/0953-8984/23/10/105304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We have studied the coupled surface plasmon (SP) modes in periodic metal nanoshell chains by including long range electromagnetic interactions. The eigen-decomposition method is used to analyze the dispersion and dissipation of the SP modes. The resulting band structure can be understood as a hybridization between a hole band and a particle band with a structurally tunable band gap in the middle of the first Brillouin zone. The mode quality, which is defined as the imaginary part of the generalized polarizability, increases as the shell thickness decreases. This indicates a larger energy loss and an increasing coupling between the bands. Through the manipulation of the band structures, the propagation of the coupled SP modes in the nanoshell chain can be controlled.
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Affiliation(s)
- C W Ling
- Department of Physics, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, People's Republic of China
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27
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Kim DJ, Lee J, Yu KW, Yoon TJ. Innate immune stimulation of polysaccharide fraction from grape peel. Food Sci Biotechnol 2011. [DOI: 10.1007/s10068-011-0015-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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28
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Kim H, Jeong JH, Hwang JH, Jeong HS, Lee HY, Yu KW. Enhancement of immunostimulation and anti-metastasis in submerged culture of bearded tooth mushroom (Hericium erinaceum) mycelia by addition of ginseng extract. Food Sci Biotechnol 2010. [DOI: 10.1007/s10068-010-0180-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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Lee SM, Lee HS, Lee J, Yu KW, Kim KM, Ra KS, Lee SP, Suh HJ. Non-pungent Capsicum fermentation by Bacillus subtilis P3-3 and its swimming endurance capacity in mice. Enzyme Microb Technol 2010. [DOI: 10.1016/j.enzmictec.2010.06.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Joung EM, Kim HY, Hwang IG, Jeong JH, Yu KW, Lee JS, Jeong HS. Changes of Antioxidant Activities on Cultured Ginseng with Mushroom Mycelia During Cultivation. ACTA ACUST UNITED AC 2010. [DOI: 10.3746/jkfn.2010.39.9.1346] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Choi JW, Ra KS, Kim SY, Yoon TJ, Yu KW, Shin KS, Lee SP, Suh HJ. Enhancement of anti-complementary and radical scavenging activities in the submerged culture of Cordyceps sinensis by addition of citrus peel. Bioresour Technol 2010; 101:6028-6034. [PMID: 20299211 DOI: 10.1016/j.biortech.2010.02.083] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2009] [Revised: 10/27/2009] [Accepted: 02/22/2010] [Indexed: 05/29/2023]
Abstract
To investigate the optimal conditions for the production of Cordyceps sinensis by the submerged culture method, glucosamine and exopolysaccharide (EPS) productivities were determined in culture broth containing different carbon sources, principally rice bran and citrus peel. An optimal medium composition (1.5% rice bran, 0.5% molasses, 3% CSL, 0.1% KH(2)PO(4), and 0.05% MgSO(4)) and the optimal condition (25 degrees C and 5-6 d culture time) for high EPS productivity with potent immune-stimulating activities were obtained. The addition of citrus peel to the culture of C. sinensis under the optimized conditions improved EPS productivity and glucosamine content. Furthermore, anti-complementary activity was higher (58.0-80.8%) using citrus peel as compared to no addition of citrus peel (48.2-68.7%). Antioxidant activity (AEAC value) of the citrus peel culture was high (284.3-384.6 mg/100g) compared to that of the culture without citrus peel (142.8-219.5mg/100g), indicating that the citrus peel helped enhance the anti-complementary and antioxidant activities of C. sinensis.
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Affiliation(s)
- Jang Won Choi
- Department of Bioindustry, Daegu University, Kyungbuk 712-714, Republic of Korea
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Kwon SC, Choi GH, Yu KW, Lee KH. Microbiological and Physicochemical Changes of Vegetable Juices (Angelica keiskei and Brassica loeracea var. acephala) Treated by UV Irradiation. ACTA ACUST UNITED AC 2010. [DOI: 10.3746/jkfn.2010.39.7.1030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Kim D, Lee J, Kim KJ, Hong HC, Shin KS, Yu KW. Macrophage stimulating polysaccharide purified from peels of grape (Vitis labrusca). Food Sci Biotechnol 2010. [DOI: 10.1007/s10068-010-0067-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Kim HY, Joung EM, Hwang IG, Jeong JH, Yu KW, Lee JS, Jeong HS. Effect of Fermented Ginseng Extract by Mushroom Mycelia on Antiproliferation of Cancer Cells. ACTA ACUST UNITED AC 2010. [DOI: 10.3746/jkfn.2010.39.1.036] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Gao Y, Huang JP, Liu YM, Gao L, Yu KW, Zhang X. Optical negative refraction in ferrofluids with magnetocontrollability. Phys Rev Lett 2010; 104:034501. [PMID: 20366645 DOI: 10.1103/physrevlett.104.034501] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2009] [Indexed: 05/29/2023]
Abstract
We numerically demonstrate optical negative refraction in ferrofluids containing isotropic Fe3O4 nanoparticles, each having an isotropic Ag shell, in the presence of an external dc magnetic field H. The all-angle broadband optical negative refraction with magnetocontrollability arises from H-induced chains or columns. They result in hyperbolic equifrequency contour for transverse magnetic waves propagating in the system. The finite element simulations verify the analyses using the effective medium approximation. Experimental demonstration and potential applications are suggested and discussed.
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Affiliation(s)
- Y Gao
- Department of Physics and Surface Physics Laboratory (National Key Laboratory), Fudan University, Shanghai 200433, China
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Kim H, Park CK, Jeong JH, Jeong HS, Lee HY, Yu KW. Immune Stimulation and Anti-Metastasis of Crude Polysaccharide from Submerged Culture of Hericium erinaceum in the Medium Supplemented with Korean Ginseng Extracts. ACTA ACUST UNITED AC 2009. [DOI: 10.3746/jkfn.2009.38.11.1535] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Wei EB, Yu KW. Localization of the electric-field distribution in graded core-shell metamaterials. Phys Rev E Stat Nonlin Soft Matter Phys 2009; 80:046607. [PMID: 19905471 DOI: 10.1103/physreve.80.046607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2009] [Revised: 07/31/2009] [Indexed: 05/28/2023]
Abstract
The local electric-field distribution has been investigated in a core-shell cylindrical metamaterial structure under the illumination of a uniform incident optical field. The structure consists of a homogeneous dielectric core, a shell of graded metal-dielectric metamaterial, embedded in a uniform matrix. In the quasistatic limit, the permittivity of the metamaterial is given by the graded Drude model. The local electric potentials and hence the electric fields have been derived exactly and analytically in terms of hypergeometric functions. Our results showed that the peak of the electric field inside the cylindrical shell can be confined in a desired position by varying the frequency of the optical field and the parameters of the graded profiles. Thus, by fabricating graded metamaterials, it is possible to control electric-field distribution spatially. We offer an intuitive explanation for the gradation-controlled electric-field distribution.
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Affiliation(s)
- En-Bo Wei
- Institute of Oceanology and KLOCW, Chinese Academy of Sciences, Qingdao, People's Republic of China.
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Park CK, Kim H, Tu Q, Yu KW, Jeong HS, Lee HY, Jeong JH. Chemical Composition and Immunostimulating Activity of the Fermented Korean Ginseng (Panax ginseng C.A. Meyer) with Mushroom Mycelium by Solid Culture. ACTA ACUST UNITED AC 2009. [DOI: 10.3746/jkfn.2009.38.9.1145] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Joung EM, Hwang IG, Lee HY, Jeong JH, Yu KW, Jeong HS. Changes of Saponin and β-Glucan Content on the Cultured Ginseng with Mushroom Mycelia. ACTA ACUST UNITED AC 2009. [DOI: 10.3746/jkfn.2009.38.8.1084] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Lee SM, Kim SY, Lee J, Yu KW, Chang I, Suh HJ. Nonpungent Capsicum fermentation by Bacillus subtilis and the addition of Rapidase. Appl Microbiol Biotechnol 2008; 81:257-62. [DOI: 10.1007/s00253-008-1658-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2008] [Revised: 08/04/2008] [Accepted: 08/06/2008] [Indexed: 10/21/2022]
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Gao L, Fung TH, Yu KW, Qiu CW. Electromagnetic transparency by coated spheres with radial anisotropy. Phys Rev E Stat Nonlin Soft Matter Phys 2008; 78:046609. [PMID: 18999553 DOI: 10.1103/physreve.78.046609] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2008] [Indexed: 05/27/2023]
Abstract
We establish an account of electromagnetic scattering by coated spheres with radial dielectric and magnetic anisotropy. Within full-wave scattering theory, we show that the total scattering cross section Qs is strongly dependent on both the dielectric anisotropy and magnetic anisotropy. As a consequence, by a suitable adjustment of the radius ratio, one may make the anisotropic coated particle nearly transparent or invisible. In the quasistatic case, we take one step forward to derive the effective permittivity and permeability for the coated particle, and the near-zero scattering radius ratio can be well described within effective medium theory. To one's interest, the introduction of radial anisotropy is helpful to achieve better transparency quality such as a much smaller Qs and wider range of near-zero scattering ratio. Moreover, when the coated particle is anisotropic, the position of the near-zero scattering radius ratio can be tunable, resulting in a tunable electromagnetic cloaking.
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Affiliation(s)
- L Gao
- Department of Physics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, China.
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Yoon TJ, Yu KW, Shin KS, Suh HJ. Innate immune stimulation of exo-polymers prepared from Cordyceps sinensis by submerged culture. Appl Microbiol Biotechnol 2008; 80:1087-93. [PMID: 18690428 DOI: 10.1007/s00253-008-1607-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2008] [Revised: 07/02/2008] [Accepted: 07/07/2008] [Indexed: 11/27/2022]
Abstract
After we prepared exo-polymers (EPS) from Cordyceps sinensis by submerged culture, prophylactic intravenous administration (i.v.) of EPS significantly inhibited metastasis in experimental lung metastasis of colon 26-M3.1 carcinoma. Cytotoxicity against Yac-1 tumor cells of natural killer (NK) cell, which was prepared by i.v. of EPS (100 mug/mouse), significantly augmented 2 days after EPS treatment. When NK cells were depleted by rabbit anti-asialo GM1 serum, even the EPS group totally abolished the inhibitory effect on lung metastasis of colon 26-M3.1 cells. EPS can stimulate innate immune system to inhibit tumor metastasis, and its anti-tumor metastasis is associated with macrophage and NK cell activation.
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Affiliation(s)
- Taek Joon Yoon
- Department of Food and Nutrition, Yuhan College, Bucheon, South Korea
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Fan CZ, Huang JP, Yu KW. Dielectrophoresis of an Inhomogeneous Colloidal Particle under an Inhomogeneous Field: A First-Principles Approach. J Phys Chem B 2006; 110:25665-70. [PMID: 17181204 DOI: 10.1021/jp062397k] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In reality, colloidal particles often possess an arbitrary inhomogeneity profile. We present a first-principles approach to dielectrophoresis of such an inhomogeneous colloidal particle under an inhomogeneous field of an oscillating electric dipole moment. For numerical simulations, we treat the inhomogeneous particle as a specific graded one with a physically motivated dielectric model and conductivity profile. We find that both multipolar interactions and spatial fluctuations inside the particle can affect the dielectrophoretic spectrum of the particle significantly.
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Affiliation(s)
- C Z Fan
- Surface Physics Laboratory (National Key Laboratory) and Department of Physics, Fudan University, Shanghai 200433, China
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Tian WJ, Huang JP, Yu KW. Dynamic effects on nonlinear alternating current responses in electrorheological fluids. Phys Rev E Stat Nonlin Soft Matter Phys 2006; 73:031408. [PMID: 16605525 DOI: 10.1103/physreve.73.031408] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2005] [Indexed: 05/08/2023]
Abstract
By using a perturbation approach, we investigate dynamic effects on nonlinear alternating current (ac) responses in electrorheological (ER) fluids under an ac or direct current electric field. We show that the dynamic effect due to a shear flow, which exerts a torque on ER particles and thus leads to the rotation of the particles about their centers, plays a significant role in the responses. Our results can be well interpreted in the dielectric dispersion spectral representation, and they offer a convenient method to determine the relaxation time and rotation velocity of ER particles by measuring the nonlinear ac responses.
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Affiliation(s)
- W J Tian
- The State Key Laboratory of Applied Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
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Shohael AM, Chakrabarty D, Yu KW, Hahn EJ, Paek KY. Application of bioreactor system for large-scale production of Eleutherococcus sessiliflorus somatic embryos in an air-lift bioreactor and production of eleutherosides. J Biotechnol 2005; 120:228-36. [PMID: 16095745 DOI: 10.1016/j.jbiotec.2005.06.010] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2005] [Revised: 05/24/2005] [Accepted: 06/07/2005] [Indexed: 11/17/2022]
Abstract
Embryogenic callus was induced from leaf explants of Eleutherococcus sessiliflorus cultured on Murashige and Skoog (MS) basal medium supplemented with 1 mg l(-1) 2,4-dichlorophenoxyacetic acid (2,4-D), while no plant growth regulators were needed for embryo maturation. The addition of 1 mg l(-1) 2,4-D was needed to maintain the embryogenic culture by preventing embryo maturation. Optimal embryo germination and plantlet development was achieved on MS medium with 4 mg l(-1) gibberellic acid (GA(3)). Low-strength MS medium (1/2 and 1/3 strength) was more effective than full-strength MS for the production of normal plantlets with well-developed shoots and roots. The plants were successfully transferred to soil. Embryogenic callus was used to establish a suspension culture for subsequent production of somatic embryos in bioreactor. By inoculating 10 g of embryogenic cells (fresh weight) into a 3l balloon type bubble bioreactor (BTBB) containing 2l MS medium without plant growth regulators, 121.8 g mature somatic embryos at different developmental stages were harvested and could be separated by filtration. Cotyledonary somatic embryos were germinated, and these converted into plantlets following transfer to a 3l BTBB containing 2l MS medium with 4 mg l(-1) GA3. HPLC analysis revealed that the total eleutherosides were significantly higher in leaves of field grown plants as compared to different stages of somatic embryo. However, the content of eleutheroside B was highest in germinated embryos. Germinated embryos also had higher contents of eleutheroside E and eleutheroside E1 as compared to other developmental stages. This result indicates that an efficient protocol for the mass production of E. sessiliflorus biomass can be achieved by bioreactor culture of somatic embryos and can be used as a source of medicinal raw materials.
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Affiliation(s)
- A M Shohael
- Research Center for the Development of Advanced Horticultural Technology, Chungbuk National University, Cheongju, South Korea
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Dong L, Karttunen M, Yu KW. Spectral representation of the effective dielectric constant of graded composites. Phys Rev E Stat Nonlin Soft Matter Phys 2005; 72:016613. [PMID: 16090113 DOI: 10.1103/physreve.72.016613] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2005] [Indexed: 05/03/2023]
Abstract
We generalize the Bergman-Milton spectral representation, originally derived for a two-component composite, to extract the spectral density function for the effective dielectric constant of a graded composite. This work has been motivated by a recent study of the optical absorption spectrum of a graded metallic film [Huang and Yu, Appl. Phys. Lett. 85, 94 (2004)] in which a broad surface-plasmon absorption band was shown to be responsible for enhanced nonlinear optical response and an attractive figure of merit. It turns out that, unlike in the case of homogeneous constituent components, the characteristic function of a graded composite is a continuous function because of the continuous variation of the dielectric function within the constituent components. Analytical generalization to three-dimensional graded composites is discussed, and numerical calculations for multilayer composites are given as a simple application.
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Affiliation(s)
- L Dong
- Biophysics and Statistical Mechanics Group, Laboratory of Computational Engineering, Helsinki University of Technology, FIN-02015 HUT, Finland
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Yu KW, Kim YS, Shin KS, Kim JM, Suh HJ. Macrophage-stimulating activity of exo-biopolymer from cultured rice bran with Monascus pilosus. Appl Biochem Biotechnol 2005; 126:35-48. [PMID: 16014997 DOI: 10.1007/s12010-005-0004-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2004] [Revised: 04/12/2005] [Accepted: 04/12/2005] [Indexed: 10/23/2022]
Abstract
To find a new use of rice bran, five fungi were examined for the production of exo-biopolymer with macrophage-stimulating activity from rice bran. Among the exo-biopolymers produced from the cultures, Monascus pilosus had the most potent macrophage stimulating activity in a liquid culture rather than in a solid culture. In order to improve the yield of exo-biopolymer with macrophage-stimulating activity, a suitable medium for exo-biopolymer was tested in submerged culture of M. pilosus. The highest amount of exo-biopolymer (13.9 mg/mL) was obtained in a medium containing rice bran as an only carbon source followed by media with additional maltose and sucrose (13.8 and 13.7 mg/mL, respectively). The addition of peptone resulted in the production of high amount of exo-biopolymer (15.1 mg/mL), meanwhile the addition of ammonium chloride resulted in 264.0 microg/mL of glucosamine content. Among eight different kinds of inorganic salts tested, potassium phosphate (0.1%) was the most effective inorganic salt for the mycelial growth and exo-biopolymer production. Therefore the optimal medium composition was as follows (g/L): 20 g of rice bran, 5 g of peptone, and 1 g of KH2PO4. The optimal culture pH and time for mycelial growth and exo-biopolymer production was pH 5.0 and 25 degrees C, respectively. The maximum exo-biopolymer (20.1 mg/mL) was observed at the fourth day of cultivation. Exo-biopolymer, a crude polysaccharide fraction, mainly contained neutral sugar (81.8%) with considerable amounts of uronic acid (18.2%). Component sugar analysis showed that the active fraction consisted mainly of arabinose, galactose, glucose, which was digested from starch of rice bran during cultivation, and uronic acid (molar ratio; 0.8:1.0:0.7:0.8).
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Affiliation(s)
- K W Yu
- Department of Kimchi and Food Science, Chongju National College of Science and Technology, Jeungpyeong 368-701, Korea
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Chan PN, Antonio GE, Griffith JF, Yu KW, Rainer TH, Ahuja AT. Computed tomography for cervical spine trauma. The impact of MDCT on fracture detection and dose deposition. Emerg Radiol 2005; 11:286-90. [PMID: 16133623 DOI: 10.1007/s10140-005-0407-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2004] [Accepted: 01/24/2005] [Indexed: 11/30/2022]
Abstract
A multidetector computed tomography (MDCT) was installed in our department. Referral rates, examination protocols and detection rates of abnormal findings in CT examinations for cervical spine trauma 6 months before and 6 months after MDCT installation were compared to look for changes in practice. Retrospective analysis of all CT cervical spine examinations in patients with multiple trauma over two contiguous 6-month periods: from July 2003 to December 2003 (helical CT) and from January 2004 to June 2004 (MDCT). Variables recorded were number of CT examinations performed, scan plane coverage and traumatic abnormalities detected. Phantom dosimetry measurements for cervical spine examination in both helical CT and MDCT were compared. One hundred and fifty four patients underwent cervical spine CT during these periods. Helical CT period: of 91 patients undergoing CT cervical spine examination for trauma, 65 (71%) were complete cervical examinations and 26 (29%) were level-specific examinations. Eight patients (9%) had cervical spine fracture, six of which were apparent on radiographs. Dose estimations for thyroid, lens and breast were 24.76, 1.86 and 0.21 mGy, respectively, for complete cervical spine examinations. MDCT period: of 63 patients who underwent CT cervical spine examination for trauma, 61 (97%) were complete examinations and 2 (3%) were level-specific examinations. Six patients (11%) had cervical spine fracture, three of which were apparent on radiographs. Dose estimations for thyroid, lens and breast were 75.8, 9.7 and 0.7 mGy, respectively, for complete cervical spine examinations, which were notably higher than those for helical CT. After installation of MDCT, clinical requests for complete examination of the cervical spine following trauma increased. This changing trend resulted in a significantly higher radiation dose to thyroid, lens and breast.
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Affiliation(s)
- P N Chan
- Department of Diagnostic Radiology and Organ Imaging, Prince of Wales Hospital, Shatin, New Territories, Hong Kong.
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Jeong JH, Jung SJ, Murthy HN, Yu KW, Paek KY, Moon HK, Choi YE. Production of eleutherosides in in vitro regenerated embryos and plantlets of Eleutherococcus chiisanensis. Biotechnol Lett 2005; 27:701-4. [PMID: 16049737 DOI: 10.1007/s10529-005-4693-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2005] [Accepted: 03/21/2005] [Indexed: 10/25/2022]
Abstract
High frequency somatic embryogenesis of Eleutheorcoccus chiisanensis was achieved through suspension culture of embryogenic cells in hormone-free Murashige and Skoog liquid medium supplemented with 30 g sucrose l-1. Cotyledonary somatic embryos were germinated and converted into plantlets using 20 microM: gibberellic acid which were then grown in a 10 l airlift bioreactor. HPLC analysis revealed the accumulation of eleutheroside B, E and E1 in the embryos and plantlets. Thus mass production of embryos and plantlets of E. chiisanensis can be achieved in liquid cultures and the biomass produced may become an alternative source of eleutherosides.
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Affiliation(s)
- J H Jeong
- Biotechnology Division, Korea Forest Research Institute, Suwon, 441-350, Korea
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50
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Abstract
We study the effective second-harmonic generation (SHG) susceptibility in graded metallic films by invoking the local field effects exactly and further numerically demonstrate that graded metallic films can serve as a novel optical material for producing a broad structure in both the linear and the SHG response and an enhancement in the SHG signal.
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Affiliation(s)
- J P Huang
- Department of Physics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong.
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