caa a22 4500 605503443 CHVBK 20210128100610.0 cr unu---uuuuu 210128e20150701xx s 000 0 eng 10.1007/s00253-015-6711-1 doi (NATIONALLICENCE)springer-10.1007/s00253-015-6711-1 Antibacterial evaluation of flavonoid compounds against E. coli by microcalorimetry and chemometrics [Elektronische Daten] [Weijun Kong, Yanling Zhao, Xiaoyan Xing, Xinping Ma, Xiaojiao Sun, Meihua Yang, Xiaohe Xiao] Fighting against multidrug-resistant bacteria requires reliable methods to evaluate the effect of antibacterial agents. As a universal, non-destructive, and highly sensitive tool, microcalorimetry has been used in many biological investigations to provide continuous real-time monitoring of the metabolic activity. This method, based on heat-flow output, was used to evaluate the influence of two flavonoid compounds (liquiritigenin and liquiritin) on Escherichia coli. Some crucial information, such as the thermogenic power-time curve and thermokinetic parameters of E. coli growth affected by the two compounds, was obtained and further studied by chemometric techniques including similarity analysis, multivariate analysis of variance, and principal component analysis. By comparing the values of two main parameters, k 2 (growth rate constant of the second exponential phase) and Q 1 (heat output of the first exponential growth phase) of E. coli based on the box and whisker plot, liquiritigenin and liquiritin could be differentiated according to their antibacterial effects; liquiritin with IC50 (half-inhibitory concentration) of 198.6μgmL−1 expressed a stronger antibacterial effect than liquiritigenin with IC50 of 337.8μgmL−1. The glucoside group in liquiritin containing four additional free hydroxyls in the diphenylpropane skeleton was crucial for inducing the antibacterial effect. Liquiritin might be a promising candidate against E. coli. This study provides a valuable method for searching for novel antibacterial agents using microcalorimetry with chemometrics. Springer-Verlag Berlin Heidelberg, 2015 Flavonoid compounds nationallicence E. coli nationallicence Antibacterial evaluation nationallicence Microcalorimetry nationallicence Chemometrics nationallicence Kong Weijun Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, 100193, Beijing, China aut Zhao Yanling China Military Institute of Chinese Materia Medica, 302 Military Hospital of China, 100039, Beijing, China aut Xing Xiaoyan Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, 100193, Beijing, China aut Ma Xinping Department of Traditional Chinese Medicine, Air Force General Hospital, PLA, 100142, Beijing, China aut Sun Xiaojiao China Military Institute of Chinese Materia Medica, 302 Military Hospital of China, 100039, Beijing, China aut Yang Meihua Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, 100193, Beijing, China aut Xiao Xiaohe China Military Institute of Chinese Materia Medica, 302 Military Hospital of China, 100039, Beijing, China aut Applied Microbiology and Biotechnology Springer Berlin Heidelberg 99/14(2015-07-01), 6049-6058 0175-7598 99:14<6049 2015 99 253 https://doi.org/10.1007/s00253-015-6711-1 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00253-015-6711-1 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Kong Weijun Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, 100193, Beijing, China aut NATIONALLICENCE 700 1- Zhao Yanling China Military Institute of Chinese Materia Medica, 302 Military Hospital of China, 100039, Beijing, China aut NATIONALLICENCE 700 1- Xing Xiaoyan Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, 100193, Beijing, China aut NATIONALLICENCE 700 1- Ma Xinping Department of Traditional Chinese Medicine, Air Force General Hospital, PLA, 100142, Beijing, China aut NATIONALLICENCE 700 1- Sun Xiaojiao China Military Institute of Chinese Materia Medica, 302 Military Hospital of China, 100039, Beijing, China aut NATIONALLICENCE 700 1- Yang Meihua Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, 100193, Beijing, China aut NATIONALLICENCE 700 1- Xiao Xiaohe China Military Institute of Chinese Materia Medica, 302 Military Hospital of China, 100039, Beijing, China aut NATIONALLICENCE 773 0- Applied Microbiology and Biotechnology Springer Berlin Heidelberg 99/14(2015-07-01), 6049-6058 0175-7598 99:14<6049 2015 99 253