Platycodin d

Huperzine A was purchased from Shanghai Fudan Forward Pharmaceutical Co., Ltd. (Shanghai, China). Piracetam was obtained from Northeast General Pharmaceutical Factory (Shenyang, China). The In situ Cell Death Detection kit, peroxidase was from Roche (Basel, Switzerland). Protein lysis buffer for western blot was provided by Solarbio Science & Technology Co., Ltd. (Beijing, China). Antibodies directed to Bax (rabbit anti-rat; cat. no. 2772S; 1:800), c-Jun (mouse anti-rat; cat. no. 2315S; 1:500), Bcl-2 (rabbit anti-rat; cat. no. 2876S; 1:1,000), PKA C-α (rabbit anti-rat; cat. no. 4782S; 1:600), CREB (rabbit anti-rat; cat. no. 4820; 1:800), and phosphorylated CREB (p-CREB; rabbit anti-rat; cat. no. 4276; 1:500) were all from Cell Signaling Technology (Danvers, MA, USA). An antibody against β-actin (mouse anti-rat; cat. no. TA-09; 1:1,000) and secondary antibodies against peroxidase-conjugated goat anti-mouse IgG (cat. no. ZB-2305; 1:3,000) and peroxidase-conjugated goat anti-rabbit IgG (cat. no. ZB-2301; 1:3,000) were obtained from Zhongshan Jinqiao Biotechnology Co., Ltd. (Beijing, China). Notoginsenoside R1, astragaloside IV, amygdalin, platycodin D and ginsenoside Rg1 were purchased from Chengdu Must Biotechnology Co., Ltd. (Chengdu, China). Ginsenoside Rb1 was from National Institutes for Food and Drug Control (Beijing, China).

Wild PR samples were collected from 23 regions in 11 different provinces in China during September–October (Table 7, Figure 5). The growth years of all samples were determined by the bowl-shaped stem marks (known as “Luwan” in Chinese), and some samples showed clear growth rings after phloroglucinol staining method [22 (link)] (Figure 6). PR samples were authenticated as the root of Platycodon grandiflorum by Professor Huasheng Peng and deposited to Synergetic Innovation Center of Anhui Authentic Chinese Medicine Quality Improvement, Anhui University of Chinese Medicine, Hefei, China.
HPLC-grade acetonitrile was purchased from Sinopharm Chemical Reagent Co., Ltd. (Shanghai, China). HPLC-grade water was prepared using a Milli-Q water purification system from Pall Filter Co., Ltd. (Beijing, China). All other reagents were of analytical grade. Platycoside E, deapioplatycoside E, Platycodin D₃, and deapioPlatycodin D₃ were purchased from Chengdu Push Biotechnology Co., Ltd. (Chengdu, China). Platycodin D was purchased from Chengdu Must Bio-Technology Co., Ltd. (Chengdu, China). DeapioPlatycodin D, Platycodin D₂, and polygalacin D were purchased from Chengdu Biopurify Phytochemicals, Ltd. (Chengdu, China). The purity of the all saponins was higher than 98%.