Lee Kyung-Yeol, Cha Su-Mi, Choi Sung-Mi, Cha Jeong-Dan
Department of Oral Microbiology, School of Dentistry, Chonbuk National University.
J Oral Sci. 2017;59(1):77-86. doi: 10.2334/josnusd.16-0151.
The antibacterial activity of an extract and several fractions of Sophora flavescens (S. flavescens) root alone and in combination with antibiotics against oral bacteria was investigated by checkerboard assay and time-kill assay. The minimum inhibitory concentration/minimum bactericidal concentration (MIC/MBC) values for all examined bacteria were 0.313-2.5/0.625-2.5 μg/mL for the n-BuOH fraction, 0.625-5/1.25-10 μg/mL for the EtOAc fraction, 0.25-8/0.25-16 μg/mL for ampicillin, 0.5-256/1-512 μg/mL for gentamicin, 0.008-32/0.016-64 μg/mL for erythromycin, and 0.25-64/0.5-128 μg/mL for vancomycin. The n-butanol (n-BuOH) and ethyl acetate (EtOAc) fractions exhibited stronger antibacterial activity against oral bacteria than other fractions and extracts. The MICs and MBCs were reduced to between one half and one quarter when the n-BuOH and EtOAc fractions were combined with antibiotics. After 24 h of incubation, combination of 1/2 MIC of the n-BuOH fraction with antibiotics increased the degree of bactericidal activity. The present results suggest that n-BuOH and EtOAc extracts of S. flavescens root might be applicable as new natural antimicrobial agents against oral pathogens.
采用棋盘法和时间杀菌法，研究了苦参根提取物及其几个部位单独以及与抗生素联合对口腔细菌的抗菌活性。对于所有检测的细菌，正丁醇部位的最低抑菌浓度/最低杀菌浓度（MIC/MBC）值为0.313 - 2.5/0.625 - 2.5μg/mL，乙酸乙酯部位为0.625 - 5/1.25 - 10μg/mL，氨苄西林为0.25 - 8/0.25 - 16μg/mL，庆大霉素为0.5 - 256/1 - 512μg/mL，红霉素为0.008 - 32/0.016 - 64μg/mL，万古霉素为0.25 - 64/0.5 - 128μg/mL。正丁醇（n - BuOH）和乙酸乙酯（EtOAc）部位对口腔细菌的抗菌活性比其他部位和提取物更强。当正丁醇和乙酸乙酯部位与抗生素联合时，MIC和MBC降低至原来的二分之一到四分之一。孵育24小时后，正丁醇部位1/2 MIC与抗生素联合可提高杀菌活性程度。目前的结果表明，苦参根的正丁醇和乙酸乙酯提取物可能作为新型天然抗菌剂用于对抗口腔病原体。
