Mulberroside a

Cortex Mori (Batch number: PZ2021073001, Shanghai, China), Cortex Lycii (Batch number: YP2021080501, Shanghai, China) and Radix Glycyrrhizae (Batch number: PZ2021081901, Shanghai, China) were from Shanghai Kangqiao traditional Chinese medicine Co. Ltd. Japonica rice (Batch number: PZ2021081901, Shandong, China) was purchased from Shandong Shangyao traditional Chinese medicine Co. Ltd. The standards which included mulberroside A, kukoamine A (Figure 1E), kukoaMine B, liquiritin, liquiritin apioside, glycyrrhizic acid ammonium salt, mulberroside C, oxyresveratrol (Figure 1C) and schisandrin (Figure 1J) (≥98% purity) were all purchased from Shanghai Yuanye Biotechnology Co., Ltd. (Shanghai, China). Digoxin (Figure 1I) was purchased from Merck KGaA (Darmstadt, Germany). 3500Da dialysis bag was purchased from Shanghai Yuanye Biotechnology Co., Ltd. (Shanghai, China).

Mulberry samples were grinded
into powder in liquid nitrogen and
lyophilized overnight. A portion (0.5 mL) of absolute methanol was
added to a 1.5 mL EP tube containing 10 mg of dried sample, followed
by sonication for 60 min and centrifugation at 12 000g for 20 min to precipitate plant debris. The supernatants
were then filtered through a 0.22 μm nylon filter and used for
HPLC analysis. The standards of mulberroside A, oxyresveratrol, and
moracin M were purchased from Yuanye Bio-Technology (Shanghai, China),
and the others (moracin C, moracin N, morachalcone A, and chalcomoracin)
were isolated and identified by our lab.^{40 (link)}A 10 μL aliquot of extracted samples and the mixed standard
solution (10 μM for each compound in methanol) was used for
HPLC analysis on an Agilent Series 1260 liquid chromatograph (Agilent)
with a C18 column (250 mm × 4.6 mm, inner dimension: 5 mm, Agilent).
Acetonitrile (solvent A) and 0.1% formic acid in water (solvent B)
were used as the mobile phase with a flow rate of 1.0 mL min^–1 at 40 °C. The gradient conditions were optimized as follows:
0–25 min, 10∼50% A; 25–40 min, 50∼95%
A; 40–45 min, 95% A; 45–47 min, 95∼100% A; 47–52
min, 100% A. Spectra were measured at a wavelength of 320 nm.