Application of “spider-web” mode in discovery and identification of Q-markers from Xuefu Zhuyu capsule

The selection of quality control indicators in a complex system is a key scientific issue for the study of Chinese materia medica (CMM), which is directly related to its safety and efficacy. In order to scientifically understand and control the quality of CMM, quality marker (Q-marker) has been recently raised as a new concept, which provided a novel research idea for the quality control and evaluation of CMM. By a new and integrated "spider-web" mode, Q-markers of Xuefu Zhuyu capsule (XZC) were comprehensively uncovered, conducing to great improvement of quality control of XZC. Mainly established by three dimensions derived from six variables including content, stability and activity, "spider-web" mode was constructed to evaluate Q-marker property of candidate compounds by taking regression area of the tested compounds into account. The candidate compounds with larger regression area were preferentially adopted as Q-markers, which should possess the satisfactorily integrated properties of content, stability and activity. Six compounds, naringin, isoliquiritin, paeoniflorin, protocatechuic acid, neohesperidin and ferulic acid, were identified and preferred as Q-markers of XZC. Based on "spider-web" mode, Q-markers from Xuefu Zhuyu capsule were successfully screened, which would substantially perform quality control of XZC and prove the feasibility of "spider-web" mode in solving the selection of quality control indicators from compound formulae.