Neochlorogenic acid

Neochlorogenic acid (99.9%), chlorogenic acid (99.0%), and cryptochlorogenic acid (99.2%) were purchased from Yuanye Biotechnology Co., Ltd. (Shanghai, China). HPLC-grade methanol was bought from Energy Chemistry Co., Ltd. (Shanghai, China). HPLC-grade acetic acid was purchased from Sigma-Aldrich Trading Co., Ltd. (Shanghai, China). Analytical grade methanol, sodium dihydrogen phosphate, and sodium carbonate were bought from Xilong Scientific Co., Ltd. (Shantou, China). Oxalic acid was obtained from Sigma-Aldrich Trading Co., Ltd. (Shanghai, China). Citric acid was obtained from Chengdu Kelong Chemical Co., Ltd. (Sichuan, China).
10 batches of PVR samples were collected from Sichuan, Yunan, and Guizhou Provinces and authenticated as the dried root of Polygonum Viviparum by Dr. Zheng-Ming Qian. Voucher specimens were deposited at Key Laboratory of State Administration of Traditional Chinese Medicine, Dongguan, Guangdong. All crude samples were smashed into powder using a tube mill (IKA, Guangzhou, China) and passed over 50 meshes.

Methanol and acetonitrile of HPLC grade were purchased from Merck (Damstadt, Germany); ultrapure water was prepared using a Milli-Q purifying system (Millipore, Bedford, MA, USA); standard compounds of chlorogenic acid, cryptochlorogenic acid, neochlorogenic acid, isochlorogenic acid A, isochlorogenic acid B, ferulic acid, caffeic acid, loganin, proline, alanine, serine, leucine, lysine, histidine, arginine, cytidine, uridine, adenosine, and phenylalanine were obtained from Shanghai Yuanye Biotechnology Co. Ltd (Shanghai, China); 1,3‐O‐dicaffeoylquinic acid, isochlorogenic acid C, protocatechuic acid were purchased from Chengdu Prefa Technology Development Co. Ltd (Sichuan, China); quinic acid, rutin, hyperoside, astragalin, isoquercitrin were acquired by the Control of Pharmaceutical and Biological Products (Beijing, China); diosmetin, apigenin, kaempferol, kaempferol‐3‐O-rutinoside, sweroside were purchased from Chengdu Chroma Biotechnology Co. Ltd (Sichuan, China); 4,5‐O-dicaffeoylquinic acid methyl ester, luteolin, luteoloside, rhoifolin, lonicerin, secologanic acid, loganin acid, morroniside were provided by Liangwei Chemical Reagent Co. Ltd (Nanjing, China); secoxyloganin were taken from Nanjing Jingzhu Biotechnology Co. Ltd (Nanjing, China). The purity of all standard compounds was more than 98%.

Chlorogenic acid (CAS: 327-97-9), neoChlorogenic acid (CAS: 906-33-2), trans-cinnamic acid (CAS: 140-10-3), ferulic acid (CAS: 1135-24-6), p-coumaric acid (CAS: 501-98-4), caffeic acid (CAS: 331-39-5), p-hydroxybenzoic acid (CAS: 99-96-7), epicatechin (CAS: 490-46-0), (+)-catechin (CAS: 154-23-4), (−)-epigallocatechin (CAS: 970-74–1), (−)-gallocatechin (CAS: 3371-27-5), phloretin (CAS: 60-82-2) and phlorizin (CAS: 60-81-1) were purchased from Shanghai Yuanye Bio-technology Co., Ltd (Shanghai, China). All phenolic chemicals were analytical standards, with HPLC purity ≥ 98%.
Stock solutions of polyphenols were obtained by dissolving each polyphenol in methanol containing 5% dimethyl sulfoxide (DMSO). Subsequently, each polyphenol was diluted with sterilized NB medium to the appropriate concentration. All solutions were prepared fresh and filter-sterilized (pore size, 0.22 μm) prior to use.

Caffeic acid, hesperidin, rutin, liquiritin, cynaroside, and forsythoside A were provided by National Institutes for Food and Drug Control (Beijing, China). Arctiin, neochlorogenic acid, chlorogenic acid, isochlorogenic acid A, and isochlorogenic acid C were purchased from Shanghai Yuanye Bio-Technology Co., Ltd. (Shanghai, China). As for phillyrin, it was provided by Chengdu Chroma-Biotechnology Co., Ltd. (Chengdu, Sichuan Province, China). The detailed information of the above mentioned standard materials is listed in Table S1. All the herbal slices of Yinqiao powder were purchased from Beijing Tongrentang drugstore (Beijing, China), and information of these herbal slices is shown in Table 1.
The deionized water was obtained from Watsons (Watsons Food and Beverage Co., Ltd., Guangzhou, China). Acetonitrile (HPLC grade), formic acid (HPLC grade), and methanol (HPLC grade) used in UPLC analysis were provided by Fisher Scientific (Thermo Fisher, CA, USA). In quantitative analysis, acetonitrile (HPLC grade) and methanol (HPLC grade) were purchased from BCL International Trading Co., Ltd. (USA), and methanol (AR) was obtained from Tianjin Fuyu Fine Chemical Co., Ltd. (Tianjin, China).

Chlorogenic acid, neoChlorogenic acid, cryptoChlorogenic acid, arctiin, arctigenin, tectoridin, tectorigenin, iridin, irisflorentin, irigenin, matrine, oxymatrine, liquiritin, isoliquiritin, liquiritigenin, isoliquiritigenin, and galuteolin were obtained from the Shanghai YuanYe Biotechnology Co., Ltd. (Shanghai, China) for use as references. Glycyrrhizic acid and glycyrrhetinic acid were purchased from China’s National Institute for the Control of Pharmaceutical and Biological Products (Beijing, China). The purity of the reference compounds was >98% based on high-performance liquid chromatography (HPLC) analysis. SJLYKL was prepared by the Shanghai Liantang pharmacy (Shanghai, China). Deionized water was purified using a Milli-Q system (Millipore, Bedford, MA, USA). Ammonium acetate (HPLC grade; purity ≥98.0%) and acetic acid (HPLC grade; purity ≥99.7%) were provided by ANPEL Laboratory Technologies (Shanghai, China). Chromatographic grade methanol and acetonitrile were purchased from Merck (Darmstadt, Germany).

Controls, consisting of sugars (fructose, sorbitol, glucose, sucrose), organic acids (quinic acid, malic acid, citric acid, succinic acid), phenolic compounds (coumaric acid, procyanidin B1, neochlorogenic acid, catechin, vanillic acid, chlorogenic acid, epicatechin, rutin, and quercetin), and 3-octanol were bought from Shanghaiyuanye Bio-Technology Co., Ltd. (Shanghai, China). The reagents for 2,2’-azinobis (3-ethylbenzothiazoline-6-sulphonate) (ABTS⁺), 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and cupric reducing antioxidant capacity (CUPRAC) were bought from TANEE CHEMICAL LTD. Analytical-grade reagents were bought from business sources for the remaining materials.