The aim of this study is to examine the radical scavenging activity of perilla and sesame oil that Koreans traditionally consume. For DPPH radical scavenging activity, oil and its hexane/70% methanol extracts (ME) are used and for superoxide and hydroxyl radical scavenging activities, ME are used. Unrefined perilla oil, sesame oil, and refined sunflower oil are used. The yields for ME of perilla, sesame and sunflower oil are 0.57, 0.61, and 0.30%, respectively, and the amounts of phenolic compounds in ME of corresponding oil are 18.77, 88.64 and $0.05\;{\mu}g$ tannic acid/mg, respectively. $IC_{50}$ for DPPH scavenging activity of perilla, sesame and sunflower oil are 2.12, 1.91, and 3.35 mg/mL, respectively and those for ME of corresponding oils are 0.42, 0.07, and 43.11 mg/mL, respectively. In DPPH assay, the solvent used for oil sample is iso-octane and that for ME is methanol. Superoxide anion scavenging activity of ME of perilla, sesame and sunflower oil tested at 1 mg/mL concentration are 21.10, 13.25, and 3.14%, respectively. Hydroxyl radical scavenging activities of those samples tested at 1 mg/mL concentration are 86.08, 93.30, and 93.17%, respectively. In summary, the refining process seems to remove the phenolic compound during oil processing. Antiradical substances in perilla and sesame oils responsible for scavenging DPPH radicals are present in the methanol fraction, while the antiradical substances in the sunflower oil are in the lipid fraction. DPPH scavenging activity of ME of sesame oil is significantly higher than that of perilla oil (p<0.05). However, superoxide anion scavenging capacity of ME of perilla oils was found to be greater than that of both sesame and sunflower oils (p<0.05).
Park, Hee Lyun;Lee, Nae Woo;Kim, Sung Bin;Pisaniello, Dino L.
Journal of Korean Society of Occupational and Environmental Hygiene
/
v.10
no.2
/
pp.68-77
/
2000
This study was performed to evaluate tannin exposure by wooddusts for workers in furniture factories and to investigate the relationship between tannin exposure and sino-nasal cancer risk. In order to explore possible cytological changes leading to nasal cancer, we have examined 50 male furniture workers and 50 matched controls using brush cytology. The results we have obtained in this study were as follows: 1. The tannin contents of woods used in woodworking factories have been measured and varied from 0.43 to 8.72 mg tannic acid equivalent per gram wood, for reconstituted softwood and turpentine (Syncarpia glomuliferia) respectively. 2. Airborne tannins in wooddusts were also determined by area and personal exposure. The values of mean exposures for both methods are ranged from 3.1 to $5.0{\mu}g/m^3$ and from 4.6 to $14.5{\mu}g/m^3$ in furniture manufactures. 3. Over nasal cytology scores 2, the scores of study group were slightly more than control group and this kind of metaplasias seemed to be occurred over $2mg/m^3$ wooddust and $6{\mu}g/m^3$ tannin exposure. Keratinising squamous metaplasia was investigated at nasal cytology score 3 and $10{\mu}g/m^3$ tannin exposure. The nasal cytology score 4 was seemed to be atypical squamous metaplasia. 4. To find out contributing factors to nasal cytology change, odds ratio that is one of fundmental biostatistics was applied. Actually the relationship between wooddust, tannin concentration and metaplasia were not meaningful, but the relationship between working experence more than 15 years and metaplasia was calculated as 1.83. This reveals that significant clinical abnormalities could be influenced from the years of woodworking experiences. However further research is required to evaluate the significance of the data, for the purposes of sino-nasal risk assessment, standard setting to prevent nasal cancer occurrences and possibility of changing workplace.
Pure culture experiments were conducted to assess the bacteriostatic and bactericidal effects of phlorotannins (PT) isolated from Ascophyllum nodosum (brown seaweed) on Escherichia coli O157:H7. In Exp. 1, one non-O157:H7 strain (25922) and three strains of E. coli O157:H7 (3081, EDL933 and E318N) were cultured in M9 medium with PT included at 0 (control), 25, 50 or $100{\mu}g/ml$ (n = 3). Bacterial growth was monitored by $OD_{600}$ at 0, 4, 6, 12 and 24 h, and by dilution plating at 0, 4, 6 and 24 h. All strains were inhibited (p<0.001) by PT to varying degrees. At 50 or $100{\mu}g/ml$, PT prevented growth of all four strains. At $25{\mu}g\;PT/ml$, growth of 25922, 3081, E318N and EDL933 was inhibited for 6, 12 and 24 h, respectively, but 25922 and 3081 resumed growth by 12 and 24 h. Direct plating confirmed bactericidal effects of PT on all four strains at $100{\mu}g/ml$, and on EDL933 and E318N at $50{\mu}g/ml$. In Exp. 2, strains 25922 and 3081 were incubated with no tannins or with $50{\mu}g/ml$ of PT, purified condensed tannins (CT) from Quebracho (Schinopsis balansaei), or purified tannic acid from Rhus semialata (Anacardiaceae) as hydrolysable tannins (HT). Strain 3081 was unaffected by HT or CT, but was completely inhibited (p<0.001) by PT at 4, 6 and 24 h. Strain 25922 was unaffected by HT, slightly inhibited by CT, and almost eradicated by PT at 4 and 6 h. Transmission electron microscopy revealed tannin-mediated alterations to bacterial cell walls. Phlorotannins from A. nodosum exhibit growth-inhibiting and bactericidal effects in vitro against the strains of E. coli O157:H7 investigated. Anti-E. coli efficacy of A. nodosum PT is superior to that of terrestrial tannins purified from Quebracho and from Rhus semialata.
To establish a definite diagnosis for pulmonary hydatid disease, combination of radiology and serology is useful. In this study, 19 preoperative sera from patients with surgically confirmed pulmonary hydatidosis, 40 sera from patients with other parasitosis and pulmonary diseases, and 20 sera from healthy donors were evaluated using 4 different serological tests, i.e., the commercial ELISA (ELISA-kit) test, the ELISA (ELISA-lab) test prepared in our laboratory, the commercial indirect hemagglutination assay kit (IHA-kit) test, and the IHA test using sensitized sheep red blood cells with tannic acid (IHA-TA). The ELISA-kit was the most sensitive (84.2%) and the most specific test (100.0%). The ELISA-kit also demonstrated the highest positive (100.0%) and negative (95.2%) predictive values. The sensitivity of the ELISA-lab test, that we prepared, was found to be 73.6%, whereas the IHA-kit test and the IHA-TA test were found to be 73.6% and 68.4%, respectively. The specificity of these tests was 96.6%, 98.3%, and 83.3%, respectively. When all 4 tests were assessed together, it was found that the sensitivity had risen to 94.7%. When the ELISA-kit was assessed with the IHA-kit and IHA-TA together, it was found that the sensitivity was 89.5% and 84.2%, respectively. Likewise, the combination of the ELISA-lab and IHA-kit or IHA-TA allowed us to achieve a sensitivity of 84.2% in cases of pulmonary echinococcosis. In conclusion, the diagnosis would be imminent if least 2 tests were applied together.
Kim, Hyung Soo;Kim, Mi-Ja;Cheong, Chul;Kang, Soon Ah
Journal of the Korea Academia-Industrial cooperation Society
/
v.14
no.10
/
pp.5091-5096
/
2013
Houttuynia cordata Thunb is a famous traditional Chinese medicine. Also it has rich in functional and bioactive substances with outstanding immunopotentiation, anti-cancer, antimicrobial, and anti-aging effects. This study was evaluated water and 70% ethanol extracts of Houttuynia cordata Thunb using in vitro system antioxidant properties methods. The scavenging DPPH and ABTS radicals of 2 mg/mL 70% ethanol extract were 91.8 and 54.8%, respectively. Also, The FRAP assay of this showed increase in activity. In results, the antioxidant properties of 70% ethanol extract increased significantly compared to water extract(p < 0.05). Therefore, 70% ethanol extract of Houttuynia cordata Thunb may contribute to antioxidant property.
Rodriguez-Duran, Luis V.;Contreras-Esquivel, Juan C.;Rodriguez, Raul;Prado-Barragan, L. Arely;Aguilar, Cristobal N.
Journal of Microbiology and Biotechnology
/
v.21
no.9
/
pp.960-967
/
2011
Tannin acyl hydrolase, also known as tannase, is an enzyme with important applications in the food, feed, pharmaceutical, and chemical industries. However, despite a growing interest in the catalytic properties of tannase, its practical use is very limited owing to high production costs. Several studies have already demonstrated the advantages of solid-state fermentation (SSF) for the production of fungal tannase, yet the optimal conditions for enzyme production strongly depend on the microbial strain utilized. Therefore, the aim of this study was to improve the tannase production by a locally isolated A. niger strain in an SSF system. The SSF was carried out in packed-bed bioreactors using polyurethane foam as an inert support impregnated with defined culture media. The process parameters influencing the enzyme production were identified using a Plackett-Burman design, where the substrate concentration, initial pH, and incubation temperature were determined as the most significant. These parameters were then further optimized using a Box-Behnken design. The maximum tannase production was obtained with a high tannic acid concentration (50 g/l), relatively low incubation temperature ($30^{\circ}C$), and unique low initial pH (4.0). The statistical strategy aided in increasing the enzyme activity nearly 1.97-fold, from 4,030 to 7,955 U/l. Consequently, these findings can lead to the development of a fermentation system that is able to produce large amounts of tannase in economical, compact, and scalable reactors.
In order to brew Takju, Korean flour wine, it requires three necessary steps for specific brewage. One is primary brewing process and another main brewing process to sacharify and perform alcoholic fermentation. After previous two brewing passing, the mash of main brewing process mixed with 1 volume of water is commercial Takju. Three samples were obtained from three breweries and incubated at $28{\pm}1^{\circ}C$for the alcoholic fermentation. All the samples were analyzed for observation of the changes of various biochemical constituents which were contained in the mashes of two brewing processes and in Takju. The starch contents of the suspensions in the primary and main mashes, and in Takju were 28.08, 25.92, 3.83%, and decreased considerably within 36-48 hrs and thereafter slowly. The amounts of water soluble carbohydrates and reducing sugars in three steps had a tendency of decreasing within 48 hours. The initial numbers of yeasts per 1ml in the suspensions were $1.74{\times}10^8$, $1.65{\times}10^8$, $0.66{\times}10^8$, appeared the highest at 72 hours (12.66%) in main process, and in the case of Takju kept increasing untill 60 hours. The dextrin contents in the mashe of primary process through the long period were 0.34 - 0.68%, in the main one were 0.12 - 0.32%, concerning with the amylase activities which were stronger in the mash of the primary process than in that of the main. The contents of methanol and cellulose in the mashes of two processes were 3.40-0.68%, in the main one were 0.12-0.32%, concerning with the amylase activities which were stronger in the mash of the primary process than in that of the main. The contents of methanol and cellulose in the mashes of two processes were 3.40-5.98mg/ml, 0.43-0.48% during the fermentation. The consumption of crude protein the mashes of Takju revealed with time, on the contrary, the production of free amino acids and oligo-peptides were performed, depending upon the affection of proteinase. The amount of tannic acid in Takju was 0.0073-0.0098mg/ml and organic acids of these three groups increased with time and hydrogen ion concentration was 3.28-4.43.
Skin plays important roles in protecting the internal organs from the chemical-biological risk factors and ultraviolet light. Exposure to the chemical and biological stimuli has a detrimental effect on skin's structure and physiological regulation. Therefore, much attention has been paid to natural products that show biological activities such as anti-oxidation, anti-aging and anti-bacterial activities. In this study, we investigated the skin-related biological activities of Oenothera lamarckiana aerial part extract. The extract contained 229.35 mg TAE (tannic acid equivalents)/g total polyphenolic compounds and the extract showed relative high antioxidant activity ($SC_{50}$ value: $8.52{\mu}g/mL$). The $IC_{50}$ value against tyrosinase and elastase were 307.94 and $181.51{\mu}g/mL$, respectively. This suggested that O. lamarckiana can be applied to whiten skin and slow the aging of skin. O. lamarckiana extract showed a growth inhibitory effect on Staphylococcu epidermidis (minimum inhibitory concentration: $250{\mu}g/mL$). Interestingly, O. lamarckiana extract showed no inhibitory effect on Pseudomonas aeruginosa on the paper disc assay. Yet the extract inhibited the growth of Pseudomonas aeruginosa on the broth dilution assay in a dose-dependent manners. Taken together, O. lamarckiana could have good potential for development as an additive in the cosmetic industry.
1. In the comparison of survival ratio among three different methods(bark graft, veneer graft, root graft), bark graft showed the highest survival ratio and root graft was the lowest. It was shown to be significant at the level of 5% in the analysis of variance for the results. It was able to be supposed that one of the main causes for the results was the different amounts of ferric tannic acid which was formated owing to the reaction of grafting knife with tannic acid oozing from cutting faces of the tree. In juvenile tissue graft, the survival ratio of inverted radicle graft was a little higher than that of juvenile stem graft, but there was no significant difference between two methods in analysis of variance. 2. The most hairs of chestnut tree leaves were recognized as stellates on the most part of leaves except for venation. The number of rays in the stellates was ranged from 4 to 8 generally. It was shown to be highly significant differences at the level of 1% among the each race growing at the similar environmental condition in the length of ray and the distributed ratio of the stellates having different ray number. 3. Excepting for the basal width of serration there were no significant differences between $Imakita_1$, $Imakita_2$ as well as between $Teteuchi_1$, $Teteuchi_2$ at the each point of experimental items in this study. Such results made this study more useful. 4. Among the races that were growing in the similar environmental condition, there were highly significant differences at the level of 1% in the length and the width of serration. 5. The rolling of hair, the angle of serration from the leaf margin, the existence of lateral vein in the serration, the intrusion of main vein into the serration and the width of main vein were observed to be somewhat useful as the subsidiary methods for the identification of chestnut races.
This in vitro study was undertaken to observe whether citric acid application aids the attachment and proliferation of human periodontal ligament cells to the root surfaces of periodontally diseased teeth. The roots were prepared so that the comparison could be made among the control healthy root surface, citric acid demineralized and non-demineralized root planted surfaces. Prior to the cell attachment experiment, each groups were prepared for scanning electron microscopic (SEM) examinations of root surface morphology, All specimens were fixed with phosphate buffered glutaraldehydes, postfixed with phosphate buffered osmium tetraoxide and stained with phosphate buffered tannic acid. dehydrated in ethanol, critical point dried, sputter coated with gold and examined under the SEM. In the cell attachement experiment, human cultured periodontal ligament cells at concentration to $4.5{\times}\;10^4\;cells/ml$ were seeded in each culture well which contained prepared roots and incubated for 30min 1, 2, 6, 12 and 24 hours at 37, 5% $CO_2$air incubator. Than the specimens were prepared for SEM examination using, the same methods as described above. In the cell proliferation experiment, $5{\times}\;10^4\;cells/ml$ cells were seeded incubated with the specimens for 6 hours. Then, all of the specimens were moved into fresh culture well and incubated for 24, 48, and 72 hours. The cell counting was done after trypsinization, under light microscope. The results were as follows. When viewed the surface morphology prior to the cell attachment, the non acid treated root planed surface displayed scaling striation and occasional bacteria and calculus. The citric acid treated specimens displayed little debris on the surface and funnel shaped orifices of dentinal tubules. There were no apparent differences in the morphology of cells attached to the control and experiment groups. However, in initial attachement, there was a slight more enhanced appearance in attachment in citric acid treated groups than other root surfaces. After 6 hours of incubation, most of the cells initiated the alteration of cell morphology from ovoid to spindle shapes. After 24 hours of incubation, most of the cells displayed proliferated appearance and connected with each other via numerous processes. In the cell proliferation experiments, there were statistically significant increased number of cells in citic acid treated groups than other groups.
본 웹사이트에 게시된 이메일 주소가 전자우편 수집 프로그램이나
그 밖의 기술적 장치를 이용하여 무단으로 수집되는 것을 거부하며,
이를 위반시 정보통신망법에 의해 형사 처벌됨을 유념하시기 바랍니다.
[게시일 2004년 10월 1일]
이용약관
제 1 장 총칙
제 1 조 (목적)
이 이용약관은 KoreaScience 홈페이지(이하 “당 사이트”)에서 제공하는 인터넷 서비스(이하 '서비스')의 가입조건 및 이용에 관한 제반 사항과 기타 필요한 사항을 구체적으로 규정함을 목적으로 합니다.
제 2 조 (용어의 정의)
① "이용자"라 함은 당 사이트에 접속하여 이 약관에 따라 당 사이트가 제공하는 서비스를 받는 회원 및 비회원을
말합니다.
② "회원"이라 함은 서비스를 이용하기 위하여 당 사이트에 개인정보를 제공하여 아이디(ID)와 비밀번호를 부여
받은 자를 말합니다.
③ "회원 아이디(ID)"라 함은 회원의 식별 및 서비스 이용을 위하여 자신이 선정한 문자 및 숫자의 조합을
말합니다.
④ "비밀번호(패스워드)"라 함은 회원이 자신의 비밀보호를 위하여 선정한 문자 및 숫자의 조합을 말합니다.
제 3 조 (이용약관의 효력 및 변경)
① 이 약관은 당 사이트에 게시하거나 기타의 방법으로 회원에게 공지함으로써 효력이 발생합니다.
② 당 사이트는 이 약관을 개정할 경우에 적용일자 및 개정사유를 명시하여 현행 약관과 함께 당 사이트의
초기화면에 그 적용일자 7일 이전부터 적용일자 전일까지 공지합니다. 다만, 회원에게 불리하게 약관내용을
변경하는 경우에는 최소한 30일 이상의 사전 유예기간을 두고 공지합니다. 이 경우 당 사이트는 개정 전
내용과 개정 후 내용을 명확하게 비교하여 이용자가 알기 쉽도록 표시합니다.
제 4 조(약관 외 준칙)
① 이 약관은 당 사이트가 제공하는 서비스에 관한 이용안내와 함께 적용됩니다.
② 이 약관에 명시되지 아니한 사항은 관계법령의 규정이 적용됩니다.
제 2 장 이용계약의 체결
제 5 조 (이용계약의 성립 등)
① 이용계약은 이용고객이 당 사이트가 정한 약관에 「동의합니다」를 선택하고, 당 사이트가 정한
온라인신청양식을 작성하여 서비스 이용을 신청한 후, 당 사이트가 이를 승낙함으로써 성립합니다.
② 제1항의 승낙은 당 사이트가 제공하는 과학기술정보검색, 맞춤정보, 서지정보 등 다른 서비스의 이용승낙을
포함합니다.
제 6 조 (회원가입)
서비스를 이용하고자 하는 고객은 당 사이트에서 정한 회원가입양식에 개인정보를 기재하여 가입을 하여야 합니다.
제 7 조 (개인정보의 보호 및 사용)
당 사이트는 관계법령이 정하는 바에 따라 회원 등록정보를 포함한 회원의 개인정보를 보호하기 위해 노력합니다. 회원 개인정보의 보호 및 사용에 대해서는 관련법령 및 당 사이트의 개인정보 보호정책이 적용됩니다.
제 8 조 (이용 신청의 승낙과 제한)
① 당 사이트는 제6조의 규정에 의한 이용신청고객에 대하여 서비스 이용을 승낙합니다.
② 당 사이트는 아래사항에 해당하는 경우에 대해서 승낙하지 아니 합니다.
- 이용계약 신청서의 내용을 허위로 기재한 경우
- 기타 규정한 제반사항을 위반하며 신청하는 경우
제 9 조 (회원 ID 부여 및 변경 등)
① 당 사이트는 이용고객에 대하여 약관에 정하는 바에 따라 자신이 선정한 회원 ID를 부여합니다.
② 회원 ID는 원칙적으로 변경이 불가하며 부득이한 사유로 인하여 변경 하고자 하는 경우에는 해당 ID를
해지하고 재가입해야 합니다.
③ 기타 회원 개인정보 관리 및 변경 등에 관한 사항은 서비스별 안내에 정하는 바에 의합니다.
제 3 장 계약 당사자의 의무
제 10 조 (KISTI의 의무)
① 당 사이트는 이용고객이 희망한 서비스 제공 개시일에 특별한 사정이 없는 한 서비스를 이용할 수 있도록
하여야 합니다.
② 당 사이트는 개인정보 보호를 위해 보안시스템을 구축하며 개인정보 보호정책을 공시하고 준수합니다.
③ 당 사이트는 회원으로부터 제기되는 의견이나 불만이 정당하다고 객관적으로 인정될 경우에는 적절한 절차를
거쳐 즉시 처리하여야 합니다. 다만, 즉시 처리가 곤란한 경우는 회원에게 그 사유와 처리일정을 통보하여야
합니다.
제 11 조 (회원의 의무)
① 이용자는 회원가입 신청 또는 회원정보 변경 시 실명으로 모든 사항을 사실에 근거하여 작성하여야 하며,
허위 또는 타인의 정보를 등록할 경우 일체의 권리를 주장할 수 없습니다.
② 당 사이트가 관계법령 및 개인정보 보호정책에 의거하여 그 책임을 지는 경우를 제외하고 회원에게 부여된
ID의 비밀번호 관리소홀, 부정사용에 의하여 발생하는 모든 결과에 대한 책임은 회원에게 있습니다.
③ 회원은 당 사이트 및 제 3자의 지적 재산권을 침해해서는 안 됩니다.
제 4 장 서비스의 이용
제 12 조 (서비스 이용 시간)
① 서비스 이용은 당 사이트의 업무상 또는 기술상 특별한 지장이 없는 한 연중무휴, 1일 24시간 운영을
원칙으로 합니다. 단, 당 사이트는 시스템 정기점검, 증설 및 교체를 위해 당 사이트가 정한 날이나 시간에
서비스를 일시 중단할 수 있으며, 예정되어 있는 작업으로 인한 서비스 일시중단은 당 사이트 홈페이지를
통해 사전에 공지합니다.
② 당 사이트는 서비스를 특정범위로 분할하여 각 범위별로 이용가능시간을 별도로 지정할 수 있습니다. 다만
이 경우 그 내용을 공지합니다.
제 13 조 (홈페이지 저작권)
① NDSL에서 제공하는 모든 저작물의 저작권은 원저작자에게 있으며, KISTI는 복제/배포/전송권을 확보하고
있습니다.
② NDSL에서 제공하는 콘텐츠를 상업적 및 기타 영리목적으로 복제/배포/전송할 경우 사전에 KISTI의 허락을
받아야 합니다.
③ NDSL에서 제공하는 콘텐츠를 보도, 비평, 교육, 연구 등을 위하여 정당한 범위 안에서 공정한 관행에
합치되게 인용할 수 있습니다.
④ NDSL에서 제공하는 콘텐츠를 무단 복제, 전송, 배포 기타 저작권법에 위반되는 방법으로 이용할 경우
저작권법 제136조에 따라 5년 이하의 징역 또는 5천만 원 이하의 벌금에 처해질 수 있습니다.
제 14 조 (유료서비스)
① 당 사이트 및 협력기관이 정한 유료서비스(원문복사 등)는 별도로 정해진 바에 따르며, 변경사항은 시행 전에
당 사이트 홈페이지를 통하여 회원에게 공지합니다.
② 유료서비스를 이용하려는 회원은 정해진 요금체계에 따라 요금을 납부해야 합니다.
제 5 장 계약 해지 및 이용 제한
제 15 조 (계약 해지)
회원이 이용계약을 해지하고자 하는 때에는 [가입해지] 메뉴를 이용해 직접 해지해야 합니다.
제 16 조 (서비스 이용제한)
① 당 사이트는 회원이 서비스 이용내용에 있어서 본 약관 제 11조 내용을 위반하거나, 다음 각 호에 해당하는
경우 서비스 이용을 제한할 수 있습니다.
- 2년 이상 서비스를 이용한 적이 없는 경우
- 기타 정상적인 서비스 운영에 방해가 될 경우
② 상기 이용제한 규정에 따라 서비스를 이용하는 회원에게 서비스 이용에 대하여 별도 공지 없이 서비스 이용의
일시정지, 이용계약 해지 할 수 있습니다.
제 17 조 (전자우편주소 수집 금지)
회원은 전자우편주소 추출기 등을 이용하여 전자우편주소를 수집 또는 제3자에게 제공할 수 없습니다.
제 6 장 손해배상 및 기타사항
제 18 조 (손해배상)
당 사이트는 무료로 제공되는 서비스와 관련하여 회원에게 어떠한 손해가 발생하더라도 당 사이트가 고의 또는 과실로 인한 손해발생을 제외하고는 이에 대하여 책임을 부담하지 아니합니다.
제 19 조 (관할 법원)
서비스 이용으로 발생한 분쟁에 대해 소송이 제기되는 경우 민사 소송법상의 관할 법원에 제기합니다.
[부 칙]
1. (시행일) 이 약관은 2016년 9월 5일부터 적용되며, 종전 약관은 본 약관으로 대체되며, 개정된 약관의 적용일 이전 가입자도 개정된 약관의 적용을 받습니다.