Probiotic strain is known to regulate the immune system by colonizing in the intestine and interact with intestinal cell receptors of lymphoid tissue. In this study, safety of Streptococcus thermophilus KCTC14471BP and silk fibroin coating effects was evaluated with respect to mucin binding abilities and immune system modulation. S. thermophilus KCTC14471BP was coated with silk fibroin by adding 1% water-soluble calcium and 0.1% silk fibroin. S. thermophilus KCTC14471BP showed the high activities of leucine arylamidase and β-galactosidase. Regarding the antibiotic resistance tests, S. thermophilus KCTC14471BP was susceptible to ampicillin, vancomycin, gentamicin, kanamycin, streptomycin, erythromycin, clindamycin, tetracycline, and chloramphenicol. S. thermophilus KCTC14471BP coated with silk fibroin showed the improved mucin binding ability from 16.1% to 71.3% and was confirmed to have no cytotoxicity against RAW 264.7 macrophage. S. thermophilus KCTC14471BP coated with silk fibroin showed dose-dependently significant increases in pro-inflammatory cytokines IL-1β, IL-6, and TNF-α. These results suggested that S. thermophilus KCTC14471BP can be expected as a promising probiotic bacteria for applications to food industries such as fermentation or functional foods.

Abstract
서 론
재료 및 방법
    유산균 분리 및 배양
    유산균의 실크 피브로인 코팅
    효소 활성 평가
    항생제 감수성 평가
    Mucin 코팅판 부착능 시험
    세포 배양
    MTT assay 시험
    Real-time PCR 측정
    Enzyme-linked immunosorbent assay(ELISA) 확인
    통계 분석
결 과
    S. thermophilus KCTC14471BP의 효소 활성
    S. thermophilus KCTC14471BP의 항생제 감수성 확인
    S. thermophilus KCTC14471BP의 mucin binding ability에서실크 피브로인 코팅 효과
    실크 피브로인 코팅 S. thermophilus KCTC14471BP의 세포독성 평가
    실크 피브로인 코팅 S. thermophilus KCTC14471BP의 면역활성 효과
    실크 피브로인 코팅 S. thermophilus KCTC14471BP의 농도의존적 면역 활성 확인
고 찰
요 약
References

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• 허보혜(㈜종근당바이오 중앙연구소) | Bohye Heo (Probiotics Research Laboratory, Chong Kun Dang Bio Research Institute, Ansan 15604, Republic of Korea)
• 손성호(종근당건강㈜ 중앙연구소) | Sung Ho Son (R&D Center, Chong Kun Dang Healthcare, Seoul 07249, Republic of Korea)
• 권유진(㈜종근당바이오 중앙연구소) | Yoo Jin Kwon (Probiotics Research Laboratory, Chong Kun Dang Bio Research Institute, Ansan 15604, Republic of Korea)
• 권미진(종근당건강㈜ 중앙연구소) | Mi Jin Kwon (R&D Center, Chong Kun Dang Healthcare, Seoul 07249, Republic of Korea)
• 장주현(종근당건강㈜ 중앙연구소) | Joohyun Jang (R&D Center, Chong Kun Dang Healthcare, Seoul 07249, Republic of Korea)
• 신혜정(종근당건강㈜ 중앙연구소) | Hyejung Shin (R&D Center, Chong Kun Dang Healthcare, Seoul 07249, Republic of Korea)
• 김인수(종근당건강㈜ 중앙연구소) | Insu Kim (R&D Center, Chong Kun Dang Healthcare, Seoul 07249, Republic of Korea)
• 박성엽(㈜종근당바이오 중앙연구소) | Sung-Yurb Park (Probiotics Research Laboratory, Chong Kun Dang Bio Research Institute, Ansan 15604, Republic of Korea)
• 김경환(㈜종근당바이오 중앙연구소) | Kyunghwan Kim (Probiotics Research Laboratory, Chong Kun Dang Bio Research Institute, Ansan 15604, Republic of Korea)
• 김병국(㈜종근당바이오 중앙연구소) | Byoung-Kook Kim (Probiotics Research Laboratory, Chong Kun Dang Bio Research Institute, Ansan 15604, Republic of Korea)
• 신창훈(㈜종근당바이오 중앙연구소) | Chang Hun Shin (Probiotics Research Laboratory, Chong Kun Dang Bio Research Institute, Ansan 15604, Republic of Korea)
• 김병용(종근당건강㈜ 중앙연구소) | Byung-Yong Kim (R&D Center, Chong Kun Dang Healthcare, Seoul 07249, Republic of Korea) Corresponding author