The compound enzymolysis was studied to improve cloudy apple juice yield. Pectinase, cellulase and xylanase with high decomposition activity for cloudy apple juice were selected for compound enzymolysis. Response surface methodology was used to analyze the optimal additive amount. Results showed that, the effect of interaction between cellulase and xylanase on juice yield was extremely significant (P < 0.01). The optimal condition of complex enzymatic hydrolysis was: pectinase 0.16%, cellulase 0.57% and xylanase 0.12%. The better condition of compound enzymolysis was 45 °C for 60 min. The juice yield of cloudy apple juice significantly improved after optimized enzymolysis, which reached up to 83%.

Clopidogrel (CLP) and simvastatin (SV) are commonly used in combination therapies as anti‐cardiovascular drugs. However, the effect of coadministration on the absorption and metabolism of the two drugs in vivo is not clear. This study developed and validated an LC‐MS/MS method for the simultaneous determination of CLP, clopidogrel carboxylic acid (CLPCA), 2‐oxo‐clopidogrel (2‐O‐CLP), SV, and simvastatin hydroxy acid (SVA) in beagle plasma. Chromatographic separation was achieved on an InfinityLab Poroshell 120 SB‐C8 column (2.1 × 100 mm, 2.7 μm) using methanol and 0.1% formic acid in water as the mobile phase at a flow rate of 0.3 mL/min in gradient mode. The lower limits of quantification are 0.1, 0.8, 0.05, 0.05, and 0.05 ng/mL for CLP, CLPCA, 2‐O‐CLP, SV, and SVA, respectively. The selectivity, linearity, accuracy, precision, extraction recovery, matrix effect, and stability were validated within acceptable criteria. This method was successfully applied to the pharmacokinetic drug interaction study between CLP and SV, and the results revealed that combined administration affected the metabolic rate of CLP, SV, and their metabolites. This study is the first to detect CLP, CLPCA, 2‐O‐CLP, SV, and SVA simultaneously.