Milli q gradient 10 system

XN was purchased from Chengdu Must Biotechnology Co., Ltd. (Sichuan, China). The reference standard with a purity higher than 98% was applicable to HPLC-UV analysis. HPLC-grade acetonitrile, methanol, and formic acid (FA) were purchased from Thermo Fisher Scientific (Fair Lawn, NJ, USA). All the other chemicals of analytical grade were available at the workstation, Beijing Chemical Works (Beijing, China). Deionized water used throughout the experiment was purified by a Milli-Q Gradient Å 10 System (Millipore, Billerica, MA, USA). Grace Pure SPE C₁₈-Low solid-phase extraction cartridges (200 mg/3 mL and 59 μm, 70 Å) were purchased from Grace Davison Discovery Science (Deerfield, IL, USA).

Seven PMFs (polymethoxyflavonoids) reference standards (P-1, P-2, P-4, P-5, P-6, P-8, P-9) were previously extracted, isolated, and identified from Murraya paniculata (L.) in our laboratory. Their structures were fully elucidated through a comparison of their spectral data (ESI-MS and ¹H, ¹³C NMR) with published literature values. Their purities were all determined to be higher than 98% by HPLC-UV. 5,7,3′,4′,5′-pentamethoxyflavanone (P-3) was purchased from the National Institutes for Food and Drug Control (Beijing, China), and 5-demethylnobiletin (P-7) was purchased from Chengdu Biopurify Phytochemicals Ltd. (Chengdu, China). All structures for these nine PMF reference standards are shown in Table 4 and Figure 7.
HPLC grade acetonitrile, methanol, and formic acid (FA) were purchased from Thermo Fisher Scientific (Fair Lawn, NJ, USA). All other chemicals of analytical grade were available at the work station, Beijing Chemical Works (Beijing, China). Deionized water used throughout the experiment was purified by a Milli-Q Gradient Å 10 System (Millipore, Billerica, MA, USA). Grace PureTM SPE C18-low solid-phase extraction cartridges (200 mg/3 mL, 59 µm, 70 Å) for the pretreatment of biological samples were supplied by Grace Davison Discovery Science^TM (Deerfield, IL, USA).

Five reference standards including daidzein, daidzin, puerain, genistein, and genistin were purchased from Chengdu Must Biotechnology Co. Ltd. (Sichuan, China). Their structures were fully ascertained by comparing the spectra data with published literature values. Their purities were all no less than 98% by HPLC-UV analysis. HPLC grade acetonitrile, methanol, and formic acid (FA) were used and supplied by Fisher Scientific (Fair Lawn, NJ, USA). Grace Pure™ SPE C18-Low solid-phase extraction (SPE) cartridges (200 mg/3 mL, 59 μm, 70 Å) were obtained from Grace Davison Discovery Science™ (Deerfield, IL, USA). Deionized water was freshly prepared using a Milli-Q Gradient Å 10 System (Millipore, Billerica, MA, USA). All other chemicals were of analytical grade and commercially available at the work station, Beijing Chemical Works (Beijing, China).