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Ahn YJ, Sakanaka S, Kim MJ, Kawamura T, Fujisawa T, Mitsuoka T. Effect of Green Tea Extract on Growth of Intestinal Bacteria. Microbial Ecology in Health and Disease 2009. [DOI: 10.3109/08910609009140256] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Y-J. Ahn
- Central Research Institutes, Taiyo Kagaku Co., Yokkaichi, Mie, 510, Japan
- Frontier Research Program, Laboratory for Intestinal Flora, Riken, Wako, Saitama, 351-01, Japan
| | - S. Sakanaka
- Central Research Institutes, Taiyo Kagaku Co., Yokkaichi, Mie, 510, Japan
| | - M-J. Kim
- Central Research Institutes, Taiyo Kagaku Co., Yokkaichi, Mie, 510, Japan
| | - T. Kawamura
- Central Research Institutes, Taiyo Kagaku Co., Yokkaichi, Mie, 510, Japan
| | - T. Fujisawa
- Frontier Research Program, Laboratory for Intestinal Flora, Riken, Wako, Saitama, 351-01, Japan
| | - T. Mitsuoka
- Faculty of Agriculture, The University of Tokyo, Tokyo, 113, Japan
- The Institute of Physical & Chemical Research, Wako, Saitama, 351-01, Japan
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2
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Sakanaka S, Juneja LR, Taniguchi M. Antimicrobial effects of green tea polyphenols on thermophilic spore-forming bacteria. J Biosci Bioeng 2005; 90:81-5. [PMID: 16232822 DOI: 10.1016/s1389-1723(00)80038-9] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2000] [Accepted: 04/19/2000] [Indexed: 10/26/2022]
Abstract
The inhibitory action of tea polyphenols towards the development and growth of bacterial spores was examined. Among the tested Bacillus bacteria, tea polyphenols showed antibacterial effects towards Bacillus stearothermophilus, which is a thermophilic spore-forming bacterium. The heat resistance of B. stearothermophilus spores was reduced by the addition of tea polyphenols. Clostridium thermoaceticum, an anaerobic spore-forming bacterium, also exhibited reduced heat resistance of its spores in the presence of tea polyphenols. (-)-Epigallocatechin gallate, which is the main component of tea polyphenols, showed strong activity against both B. stearothermophilus and C. thermoaceticum. The heat resistance of these bacterial spores was more rapidly decreased by the addition of tea polyphenols at high temperatures.
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Affiliation(s)
- S Sakanaka
- Central Research Laboratories, Taiyo Kagaku Co. Ltd., 1-3 Takaramachi, Yokkaichi, Mie 510-0844, Japan
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Izawa M, Koseki T, Sakanaka S, Takahashi T, Hass K, Tokumoto S, Kamiya Y. Installation of new damped cavities at the Photon Factory storage ring. J Synchrotron Radiat 1998; 5:369-371. [PMID: 15263513 DOI: 10.1107/s0909049597015070] [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] [Subscribe] [Scholar Register] [Received: 08/04/1997] [Accepted: 10/31/1997] [Indexed: 05/24/2023]
Abstract
New damped cavities have been installed in the Photon Factory (PF) storage ring and successfully operated in the last scheduled user run of 1996. The new damped cavity is a simple single-cell cavity with somewhat large beam-duct holes. The part of the beam duct that is attached to the cavity is made of SiC, which works as a microwave absorber and damps the higher-order modes excited in the cavity. Because of its simple structure, the operation of the cavity is very stable and also a high power input of more than 150 kW is possible. No coupled-bunch instabilities due to the new cavity were observed during operation.
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Affiliation(s)
- M Izawa
- Light Source Division, Institute of Materials Structure Science, High Energy Accelerator Research Organization, Oho 1-1, Tsukuba-shi, Ibaraki 305, Japan
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Sakanaka S, Hinode F, Kubo K, Urakawa J. Construction of 714 MHz HOM-free accelerating cavities. J Synchrotron Radiat 1998; 5:386-388. [PMID: 15263519 DOI: 10.1107/s0909049597015343] [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] [Subscribe] [Scholar Register] [Received: 08/04/1997] [Accepted: 11/03/1997] [Indexed: 05/24/2023]
Abstract
A new 'higher-order-mode (HOM)-free' accelerating cavity has been developed which can provide an accelerating voltage of more than 400 kV per cavity at a frequency of 714 MHz. The harmful HOMs in the cavities, which can induce beam instabilities at high beam currents, were heavily damped by using four special waveguide ports and broadband microwave loads. Two cavities of this design were installed in the 1.54 GeV accelerator test facility (ATF) damping ring at KEK, and successfully stored beams. This cavity will also be very useful for synchrotron light sources. The basic design, characteristics of HOMs and construction of this cavity are reported.
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Affiliation(s)
- S Sakanaka
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba-shi, Ibaraki-ken 305, Japan
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5
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Kanaya N, Asaoka S, Sakanaka S, Maezawa H. Operational evaluation of ultrahigh-vacuum protection systems for intense-photon-flux wiggler beamlines. J Synchrotron Radiat 1998; 5:395-397. [PMID: 15263522 DOI: 10.1107/s0909049597015100] [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] [Subscribe] [Scholar Register] [Received: 08/04/1997] [Accepted: 10/31/1997] [Indexed: 05/24/2023]
Abstract
The ultrahigh-vacuum (UHV) protection system at the 2.5 GeV synchrotron radiation source (positron storage ring) at the Photon Factory allows the intense-photon-flux wiggler beamlines to operate safely during synchrotron radiation experiments for a long time. There are six high-power wiggler/undulator beamlines that provide intense photon-flux beams to the experimental hall. In the case of a possible instantaneous vacuum failure at the experimental hall, the intense photon-flux radiation from the wiggler could cause a meltdown of the titanium-alloy fast-closing valve. The authors have developed a UHV protection system. Upon a vacuum failure, the protection system can dump the positron beam by turning off the RF power in the four RF klystrons (150 kW maximum), and then initiate a blade closure of the fast-closing valve. In this paper, the operational performance of the vacuum protection system for the intense-photon-flux wiggler beamlines is evaluated and discussed regarding the actual vacuum deterioration downstream of a beamline at the experimental hall.
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Affiliation(s)
- N Kanaya
- Photon Factory, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba 305, Japan
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Katoh M, Hori Y, Kobayashi Y, Sakanaka S, Izawa M, Haga K, Honda T, Mitsuhashi T, Obina T, Pak CO, Ohmi K, Tsuchiya K, Kanaya N, Ueda A, Tadano M, Takiyama Y, Asaoka S, Nogami T, Shioya T, Mishina A, Sato Y, Tokumoto S, Takahashi T, Kasuga T, Maezawa H, Kobayashi M, Kobayakawa H. Reconstruction for the brilliance-upgrading project of the Photon Factory storage ring. J Synchrotron Radiat 1998; 5:366-368. [PMID: 15263512 DOI: 10.1107/s0909049597014118] [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: 08/04/1997] [Accepted: 10/20/1997] [Indexed: 05/24/2023]
Abstract
Reconstruction of the Photon Factory storage ring (PF ring; 2.5 GeV) is now in progress to provide very brilliant synchrotron radiation to users, i.e. the emittance is being reduced by a factor of five. Components, such as the quadrupole and sextupole magnets, vacuum chambers, beamlines and beam-position monitors, are being replaced by new ones in 16 normal-cell sections of the PF ring. The accelerating cavities, injection systems and control systems are also being replaced. Operation will commence when the improvements are completed on 1 October 1997.
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Affiliation(s)
- M Katoh
- Photon Factory, Institute of Materials Structure Science, KEK, Oho 1-1, Tsukuba, Tharaki 305, Japan
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Miyagawa C, Wu C, Kennedy DO, Nakatani T, Ohtani K, Sakanaka S, Kim M, Matsui-Yuasa I. Protective effect of green tea extract and tea polyphenols against the cytotoxicity of 1,4-naphthoquinone in isolated rat hepatocytes. Biosci Biotechnol Biochem 1997; 61:1901-5. [PMID: 9404069 DOI: 10.1271/bbb.61.1901] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [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: 02/05/2023]
Abstract
The cytoprotective effect of green tea extract and its phenolic compounds against 1,4-naphthoquinone-induced hepatotoxicity was evaluated in primary cultured rat hepatocytes. After exposure to 1,4-naphthoquinone, lactate dehydrogenase (LDH) leakage and cell viability were both improved by the presence of the tea extract and tea polyphenols. This cytoprotective effect was related to the structure of tea polyphenols, the galloyl group of (-)-epigallocatechin-3-gallate and (-)-epicatechin-3-gallate being particularly effective. The production of liquid peroxidation by 1,4-naphthoquinone was not inhibited by the tea extract nor by tea polyphenol addition. After 2 h of incubation, the protein thiol concentration was reduced by 1,4-naphthoquinone, but this reduction was prevented by the tea extract and tea polyphenols. The reduction in protein thiol content of the cells closely paralleled the LDH leakage and loss of cell viability. These results suggest that the mechanism of protection by tea polyphenols against 1,4-naphthoquinone-induced toxicity to rat hepatocytes was due to the maintenance of protein thiol levels.
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Affiliation(s)
- C Miyagawa
- Department of Food and Nutrition, Faculty of Human Life Science, Osaka City University, Japan
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Sakanaka S, Aizawa M, Kim M, Yamamoto T. Inhibitory effects of green tea polyphenols on growth and cellular adherence of an oral bacterium, Porphyromonas gingivalis. Biosci Biotechnol Biochem 1996; 60:745-9. [PMID: 8704303 DOI: 10.1271/bbb.60.745] [Citation(s) in RCA: 139] [Impact Index Per Article: 5.0] [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: 02/01/2023]
Abstract
Effects of polyphenolic compounds isolated from green tea (Camellia sinensis) on the growth and adherence of Porphyromonas gingivalis onto human buccal epithelial cells were investigated. Green tea polyphenols, especially (-)-epigallocatechin gallate (EGCg) which is a dominant component of tea polyphenols, completely inhibited the growth and adherence of P. gingivalis onto the buccal epithelial cells at concentrations of 250-500 micrograms/ml. Among the polyphenolic compounds, (-)-epicatechin gallate (ECg) and (-)-gallocatechin gallate (GCg) were effective next to EGCg in these activities. On the other hand, (+)-catechin (C(+)), (-)-epicatechin (EC), (+)-gallocatechin (GC), and (-)-epigallocatechin (EGC) had very much less activity. These results indicate that the inhibitory effect on the adherence of P. gingivalis onto the buccal epithelial cells is attributed to the presence of the galloyl moiety, which is ester-linked with the 3-OH of the catechin moiety in the polyphenolic compounds.
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Affiliation(s)
- S Sakanaka
- Central Research Laboratories, Taiyo Kagaku Co., Ltd, Mie, Japan
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Sakanaka S, Murayama K, Adachi E. [Clinical and electrophysiological studies on posterior retinitis pigmentosa]. Nippon Ganka Gakkai Zasshi 1996; 100:50-4. [PMID: 8644529] [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] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
On the basis of fundus appearance and angiographic fundus pictures, 48 cases of posterior retinitis pigmentosa were divided into pericentral type (20 cases), perimacular type (21 cases), and macular type (7 cases). We compared the 3 groups clinically and electrophysiologically. Visual acuity and visual field were progressively deteriorated in half of the cases of pericentral type two years after the initial visit. The waveform of flash electroretinogram (ERG) was negative in the pericentral type, subnormal in the perimacular type, and normal in the macular type. These ERG findings suggest that the rod function was more severely damaged in the pericentral type than in the other types. Contrary to the ERG findings, the pattern-evoked cortical potential was normal in the pericentral type, and we assumed there is less damage of the foveal function in the pericentral type.
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Affiliation(s)
- S Sakanaka
- Department of Ophthalmology, Chiba University School of Medicine, Japan
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Yokozawa T, Oura H, Nakagawa H, Sakanaka S, Kim M. Effects of a component of green tea on the proliferation of vascular smooth muscle cells. Biosci Biotechnol Biochem 1995; 59:2134-6. [PMID: 8541655 DOI: 10.1271/bbb.59.2134] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The effects of a component of green tea on the proliferation of smooth muscle cells were measured in terms of [3H]thymidine uptake. When green tea tannin mixture was added to the medium of cultured smooth muscle cells, it suppressed the proliferation of the cells dose-dependently. Similarly to the effects of the green tea tannin mixture, (-)-epigallocatechin 3-O-gallate, its main ingredient, had an inhibitory effect on smooth muscle cell proliferation at a low concentration. (-)-Epicatechin 3-O-gallate was also an effective component. Among four types of gallate-free tannin, (-)-epigallocatechin, (-)-epicatechin, and (+)-catechin showed significant dose-dependent inhibition of smooth muscle cell proliferation. However, caffeine and theanine were found to have no such action.
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Affiliation(s)
- T Yokozawa
- Research Institute for Wakan-Yaku, Toyama Medical and Pharmaceutical University, Japan
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Yamamura T, Kondo T, Sakanaka S, Kozovska M, Geng TC, Takahashi K, Tabira T. Analysis of T cell antigen receptors of myelin basic protein specific T cells in SJL/J mice demonstrates an alpha chain CDR3 motif associated with encephalitogenic T cells. Int Immunol 1994; 6:947-54. [PMID: 7524642 DOI: 10.1093/intimm/6.7.947] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [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: 01/25/2023] Open
Abstract
Experimental autoimmune encephalomyelitis (EAE) is an animal autoimmune disease mediated by CD4+ T cells. Analysis of TCR expression revealed that limited TCR elements (V beta 8.2, V alpha 2 or 4) were utilized by myelin basic protein (MBP) specific T cells in mice with H-2u haplotype and Lewis rats. The usage of a particular beta chain complementarity determining region 3 (CDR3) motif has also been shown. However, it remains unclear to what extent these observations can be extrapolated. Here we studied the TCR sequences of MBP 89-101/I-A(s) specific T cell clones derived from SJL/J mice, using the polymerase chain reaction on reverse transcribed mRNA. Although the V beta usage was less restricted than in H-2u mice, they predominantly utilized V beta 17a and expressed LGG or related motifs in the V beta-D beta-J beta junctions. Furthermore, a single alpha chain rearrangement between V alpha 1.1 and J alpha BBM142 with no N region diversity was preferentially used. Concordantly, immunization with a peptide corresponding to the alpha chain CDR3 was found to significantly alter the clinical course of EAE. Comparison of the published TCR junctional regions demonstrates that the CDR3 motifs (LGG in beta chain, CA*R*NY motif in alpha chains) are expressed by other encephalitogenic clones. Notably, the CA*R*NY was conserved in PL/J mice clones that recognize a distinct MBP-MHC determinant. It suggests that an antigen-independent mechanism may contribute to conserving the alpha chain motif. The implications of these observations are discussed.
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Affiliation(s)
- T Yamamura
- Department of Demyelinating Disease and Aging, National Institute of Neuroscience, Tokyo, Japan
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Abstract
A major purpose of this study was to examine inhibitory effect of the catechin derivatives from Japanese green tea Camellia sinensis on collagenase activity. The crude tea catechins, which contain (+)-catechin (C), (-)-epicatechin (EC), (+)-gallocatechin (GC), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECg), and (-)-epigallocatechin gallate (EGCg), were tested for their ability to inhibit the prokaryotic and eukaryotic cell derived collagenase activities. Among the tea catechins tested, ECg and EGCg showed the most potent inhibitory effect on collagenase activity when an optimal concentration of tea catechins (100 micrograms/ml) was added to reaction mixture containing collagenase and collagen. Preincubation of collagenase with tea catechins reduced the collagenase activity as well. In contrast to ECg and EGCg, the other four tea catechins (C, EC, EGC, and GC) did not show any collagenase inhibitory effect. Our results suggest that the steric structure of 3-galloyl radical is important for the inhibition of collagenase activity. The collagenase activity in the gingival crevicular fluid from highly progressive adult periodontitis was completely inhibited by the addition of tea catechins. These results demonstrated that tea catechins containing galloyl radical possess the ability to inhibit both eukaryotic and prokaryotic cell derived collagenase.
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Affiliation(s)
- M Makimura
- Nihon University School of Dentistry at Matsudo, Department of Clinical Pathology, Japan
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Yokozawa T, Oura H, Hattori M, Iwano M, Dohi K, Sakanaka S, Kim M. Inhibitory effect of tannin in green tea on the proliferation of mesangial cells. Nephron Clin Pract 1993; 65:596-600. [PMID: 8302416 DOI: 10.1159/000187570] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The effect of green tea tannin on the proliferation of mesangial cells was determined in terms of [3H]thymidine uptake. When green tea tannin was added to the medium of mesangial cell cultures, it suppressed the proliferation of mesangial cells markedly. In particular, (-)-epigallocatechin 3-O-gallate, the predominant component of the green tea tannin mixture, exerted an inhibitory effect at a relatively low concentration, suggesting a direct corroboration of the renal effects.
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Affiliation(s)
- T Yokozawa
- Research Institute for Wakan-Yaku, Toyama Medical and Pharmaceutical University, Japan
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Ahn YJ, Sakanaka S, Kim MJ, Kawamura T, Fujisawa T, Mitsuoka T. Effect of Green Tea Extract on Growth of Intestinal Bacteria. Microbial Ecology in Health & Disease 1990. [DOI: 10.3402/mehd.v3i6.7559] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Abstract
Flavonoids, triterpenoids, and steroids were isolated from the leaves of Leucoseptrum stellipillum (MIQ). Kitamura et Murata and identified as apigenin, luteolin, chrysoeriol, ursolic acid, pomolic acid, tormentic acid, beta-sitosterol, and beta-sitosterol glucoside by comparison of their spectral data with those of authentic specimens. Among these compounds, the triterpenoids showed significant antibacterial activities against Streptococcus mutans.
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