Narirutin

The standard reference materials of amygdalin, narirutin, neohesperidin and digoxin were purchased from Yuanye Bio-Technology Co., Ltd (Shanghai, China). digoxin is not the endogenous compound of XFZYD and plasma, and it does not obviously interfere with the retention times of all three analytes. Qualitative analysis was carried out using an LC-MS system (Shimadzu 8050, Kyoto, Japan) in negative ion mode. The plasma samples were added with digoxin, and then vortex mixed for 1 min and centrifuged for 15 min (13,000 rpm, 4°C) after being added with acetonitrile. The obtained supernatants were dried in a nitrogen dryer, diluted with 10% acetonitrile-water, repeated the extraction above, and injected into the LC-MS for analysis.

HPLC-grade n-hexane (ACS, Wilmington, NC, USA), formic acid (Kermel, Tianjin, China) and isopropanol (≥99.9%, HPLC/ACS-grade) for HPLC analysis were purchased from Energy Chemical Co., Ltd. (Shanghai, China). HPLC-grade methanol was obtained from Concord Technology Co., Ltd. (Tianjin, China). The chiral flavonoid standards of hesperidin and narirutin (mixture of one pair of epimers) were purchased from Shanghai yuanye Bio-Technology Co., Ltd. (Shanghai, China).

SMD, used for gastrointestinal dysmotility in China (approval number: guo-yao-zhun-zi Z20025044; specification: 10 mL/division), was obtained from Hunan Hansen Pharmaceutical Company, Ltd. (Yi Yang, China). HSA was acquired from Sigma Chemical Co. (St. Louis, MO, USA), standards, including arecaidine, arecoline, norisoboldine, linderane, costunolide, dehydrocostus lactone, synephrine, rutin, limonin, eriocitrin, narirutin, naringin, hesperidin, heohesperidin, poncirin, naringenin, hesperetin, nobiletin, tangeretin, and sorbic acid with a purity of over 98%, were purchased from Yuan-ye Bio-Technology Co., Ltd. (Shanghai, China). The formic acid, acetonitrile, and methanol used for HPLC analysis were chromatographic grade and purchased from Sinopharm Chemical Reagent Co., Ltd. (Shanghai, China).

We accurately weighed 2 mg of each of the following: narirutin, hesperidin, nobiletin, tangeretin, and 5-demethylnobiletin (Shanghai Yuanye Biological Technology Co., Ltd. China). Then, the standard substances were dissolved in methanol (HPLC grade) individually to afford standard solutions of different concentrations. Then, 5 mg of GPE was dissolved in methanol (1 ml). This sample solution was filtered through a microporous membrane (0.22 μm) to afford the test solution.
The chromatographic separation conditions were carried out as follows: a liquid chromatography system (UltiMate3000 HPLC System, Thermo Fisher Scientific, Waltham, MA, United States) with a Welch C18 column (4.6 × 250 mm long, 5 μm) was used, mobile phase A was acetonitrile (HPLC grade), and mobile phase B was 0.5% glacial acetic acid aqueous solution. The mobile phase gradient was as follows: 0 min, 12% A; 0–20 min 25% A; 20–35 min 45% A; 35–40 min, 100% A. The flow rate was set at 0.5 ml/min, and the column temperature was 35°C. The injection volume was 5 μl, and the detection wavelength was 285 nm. The sample solution and standard solutions of different concentrations were analysed under these conditions. The compounds in GPE were analysed according to the chromatographic peak area of the standard substance.

Eleven samples of Aurantii fructus (AF) samples from different habitats were collected and identified by Associate Professor Tang Qi. Reference standards included synephrine, eriocitrin, neoeriocitrin, rutin, narirutin, naringin, hesperidin, neohesperidin, limonin, xanthotol, poncirin, naringenin, hesperetin, nobiletin, tangeretin and auraptene with a purity of over 98% were purchased from Yuan-ye Bio-Technology Co., Ltd. (Shanghai, China). Chromatographic grade formic acid, methanol, ethanol and acetonitrile were purchased from Sinopharm Chemical Reagent Co., Ltd. (Shanghai, China) and used for extractive and analytical procedures.

Naringenin, eriodictyol, apigenin, luteolin, liquiritigenin, butin, sakuranetin, kaempferol, quercetin, dihydrokaempferol, dihydroquercetin, eriocitrin, pinocembrin, narirutin, naringin, chrysin, genkwanin, baicalein, scutellarein, norwogonin, wogonin, and neoeriocitrin were purchased from Shanghai Yuanye Bio-Technology Co., Ltd (Shanghai, China). Hesperidin, neoHesperidin, sinensetin, isosinensetin, and nobiletin were obtained from Sigma-Aldrich (St Louis, MO, USA). 7-O-methyleriodictyol, isosakuranetin, and 5-HPMF were purchased from BioBioPha Co., Ltd (Kunming, China).