Salmonellosis is the commonest zoonosis worldwide that generally causes enterocolitis and foodborne poisoning which represents a considerable public health burden. Salmonella spp. are potential enteric pathogens and intracellularly replicates in host cells resulting in chronic infections. The medical treatments for salmonellosis have been difficult yet and had a serious problem including the increasing emergence of antibiotic resistance. The present report was designated to investigate the antibacterial effects of Saururus chinensis Baill ethanol extract (SCEE) on pure culture and infection with Salmonella enterica serovar Typhimurium (S. typhimurium) in murine derived macrophage RAW 264.7 cells. In determination of antibacterial activity of SCEE against S. typhimurium, bacterial viability was markedly decreased compared to the control. Also, SCEE significantly induced morphological change (p<0.05) of RAW 264.7 cells. In infection assay of S. typhimurium in RAW 264.7 cells pretreated with 100㎍/㎖ of SCEE, which is a non-cytotoxic concentration, bacterial uptake ability of macrophage was increased corresponding with morphological change, whereas bacterial survival rates within macrophage were markedly reduced compared with untreated control. Furthermore, nitric oxide (NO) production in SCEE-treated cells was slightly increased until 2 h but showed a tendency of decrease after 4 h until 24 h post infection compared with untreated control with S. typhimurium infection. Taken together, these findings demonstrated that SCEE has the antibacterial activity for S. typhimurium and the protective effects against S. typhimurium infection through activating murine macrophage independent on NO, suggesting that SCEE may be beneficial on the disease caused by intracellularly replicating pathogens as a safe alternatives of conventional chemotherapies.

ABSTRACT
 서 론
 재료 및 방법
  1. 삼백초 추출물 제조
  2. 균주 배양 및 배지
  3. 항균 효과 검증
  4. 세포 배양 및 세포 독성 검사
  5. 대식세포의 형태변화 효과
  6. 대식세포에 있어 세균의 침입 및 세포 내 증식양상
  7. Nitric oxide (NO) 농도 측정
  8. 통계처리
 결 과
 고 찰
 참고문헌

• 이진주(경상대학교 수의과대학 수의학과) | Jin-ju Lee (College of Veterinary Medicine, Gyeongsang National University)
• 김동혁(경상대학교 수의과대학 수의학과) | Dong-hyeok Kim (College of Veterinary Medicine, Gyeongsang National University)
• 임정주(경상대학교 수의과대학 수의학과) | Jeong-ju Lim (College of Veterinary Medicine, Gyeongsang National University)
• 김대근(경상대학교 수의과대학 수의학과) | Dae-geun Kim (College of Veterinary Medicine, Gyeongsang National University)
• 김곤섭(경상대학교 수의과대학 수의학과) | Gon-sub Kim (College of Veterinary Medicine, Gyeongsang National University)
• 민원기(경상대학교 수의과대학 수의학과) | Wongi Min (College of Veterinary Medicine, Gyeongsang National University)
• 이후장(경상대학교 수의과대학 수의학과) | Hu-jang Lee (College of Veterinary Medicine, Gyeongsang National University)
• 장홍희(경상대학교 농업생명과학연구원) | Hong Hee Chang (Institute of Agriculture and Life Science, Gyeongsang National University)
• 김석(경상대학교 농업생명과학연구원) | Suk Kim (Institute of Agriculture and Life Science, Gyeongsang National University) Correspondence