Analytical grade methanol

MS grade acetonitrile (ACN), methanol and formic acid were purchased from Thermo-Fisher (Pittsburgh, PA). Analytical grade methanol was obtained commercially from Beijing Chemical Works (Beijing, China). The ultra-pure water was prepared in-lab using a Milli-Q Integral water purification device (Milli-pore, MA). All materials related to Ganoderma lucidum, such as the fruit bodies (FGL) and the spore powders (SGL) of Ganoderma lucidum (Leyss. ex Fr.) Karst, and the fruit bodies of Ganoderma sinense J.D. Zhao, L.W. Hsu and X.Q. Zhang (FGS) were supplied by Xianzhilou Biotech Co. Ltd. (Nanping, China). A portion of FGL was further cut into stipes (sFGL) and pileus (pFGL) as well as FGS. The voucher specimens are deposited in the herbarium of our institute. Authentic compounds, including ganoderic acid A, were purchased from Yuanye Bio-Technology Co., Ltd. (Shanghai, China).

In this study, all 33 PAC samples were collected from natural distribution areas of wild Phellodendron amurense Rupr., which were typical and representative sample plots in Heilongjiang, Jilin, and Liaoning (Table 5). The samples were collected from 2013 to 2015, then air-dried and stored at −38 °C.
Acetonitrile (HPLC grade) was purchased from Merck KGaA (Darmstadt, Germany). Pure water (18.2 M) was purified by Milli-Q system (Millipore, Billerica, MA, USA) and used to prepare buffer and sample solutions. Analytical grade methanol was purchased from Beijing Chemical Works (Beijing, China). Ammonium bicarbonate (HPLC grade) was purchased from Mreda Technology Inc. (Fair lawn, NJ, USA). The reference standard compounds of magnoflorine, phellodendrine, jatrorrhizine, palmatine, berberine, obaculactone and obacunone (purity >98%) were purchased from Phytomarker Ltd. (Tianjin, China), while 3-O-feruloylquinic acid, 4-O-feruloylquinic acid and syringin (purity >98%) references were purchased from Wuhan ChemFaces Biochemical Co, Ltd. (Wuhan, China).