Naringenin 7 o glucoside

Citri Reticulatae Pericarpium was supplied by Scientific Research Institute of Beijing Tongrentang Co., Ltd. Total 21 reference standards, including vicenin-2 (6), vicenin-3 (25), eriocitrin (40), isoquercitroside (45), troxerutin (49), rhoifolin (66), naringin (67), naringenin (68), naringenin-7-O-glucoside (71), hesperidin (78), neohesperidin (82), hesperetin (108), isosinensetin (122), sinensetin (133), quercetagetin-3,5,6,7,3′,4′-hexamethyl ether (144), nobiletin (151), 4´,5,6,7-tetramethoxyflavone (153), tangeretin (168), 5-demethylnobiletin (174), 8-hydroxy-3,5,6,7,3′,4′-hexamethoxyflavone (180), 5-hydroxy-3,7,3',4'-tetramethoxyflavone (181), were purchased from Shanghai Yuanye Bio-Technology Co., Ltd. (Shanghai, China). The purity of all the reference standards was > 98%. The distilled water was obtained from Watsons, whereas LC–MS grade formic acid was obtained from Fisher-Scientific (Fair Lawn, USA). The LC–MS-grade acetonitrile and methanol were purchased from Merck (Germany).

Methanol (HPLC grade, 99.9%), ethanol (HPLC grade, 99.8%), acetonitrile (LC/MS grade, 99.9%), and formic acid (LC/MS grade) were all purchased from Thermo Fisher Scientific Technology Co., Ltd. (Shanghai, China). Standard compounds, namely, punicalagin, punicalin, corilagin, ellagic acid, gallic acid, catechin, epicatechin, epicatechin gallate, gallocatechin, epigallocatechin, epigallocatechin gallate, kaempferol-3-O-glucoside, isoquercitrin, luteolin-7-O-glucoside, naringenin-7-O-glucoside, and rutin, were all purchased from Yuanye Biotechnology Co., Ltd. (Shanghai, China).