Daidzin

Daidzin (7-(β-d-glucopyranosyloxy)-4′-hydroxyisoflavone) and daidzein (4′,7-dihydroxyisoflavone) were purchased from Tokyo Chemical Industry Co. Ltd. (Tokyo, Japan). LPS (Escherichia coli O111:B4), Griess reagent and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reagent were obtained from Sigma-Aldrich (St. Louis, MO, USA). All the primary antibodies used in this study were purchased from Cell Signaling Technology (Beverly, MA, USA); while the secondary antibodies and enzyme-linked immunosorbent assay (ELISA) kits for interleukin-6 (IL-6) and TNF-α were acquired from Beyotime Biotechnology (Shanghai, China).

The acidothermophilic Alicyclobacillus sp. A4 (whole genome sequenced) isolated from the hot spring water was stored in our laboratory [1 (link)]. GH3 β-glucosidase Bgl3A derived from Talaromyces leycettanus JCM12802 [376] was used as the reference. Ni²⁺-affinity beads from Suzhou Beaver Biomedical Engineering (China), and glucose oxidation (GOD-POD) kit from Beijing Leadman (China) were purchased. Substrates of p-nitrophenyl β-d-glucopyranoside (pNPG), p-nitrophenyl α-l-arabinofuranoside (pNPAf), p-nitrophenyl β-d-xylopyranoside (pNPX), barley β-glucan, lichenan, Avicel, and standard samples of daidzein, glycitein and genistein from Sigma-Aldrich (USA), cellobiose to cellohexose, laminaritetraose and maltose from Megazyme (Ireland), and daidzin from Tokyo Chemical Industry were obtained. The soybean meal was purchased from local market. All the other reagents were of analytical grade and commercially available.

The phytochemicals were obtained as follows. Chrysoeriol (1104S), 6-O-Me-luteolin (520-11-6), 7,4′-dihydroxyflavone (1259), datiscetin (1141S), eriodictyol (0056), flavonol (1026), homoeriodictyol (1118S), isorhamnetin-3G (1228), isorhamnetin (1120S), kaempferol-3G (1243G), luteolin-7G (1126S), quercetin-3G (0074), quercetagetin (1030), rhamnetin (1136S), tamarixetin (1140S), and tricetin (1335S) were obtained from Extrasynthese (Genay, France); 2,2′,4′-trihydroxychalcone (T502), 4,2′,5′-trihydroxychalcone (22-314), and gossypetin (G500) were purchased from INDOFINE Chemical Company Inc. (Hillsborough, NJ, USA). Flavone (16012-31), morin (23416-31), and pyrogallol (29703-52) were obtained from Nacalai Tesque Inc. (Kyoto, Japan). EGCG (E4268), hyperoside (00180585-25MG), and phloroglucinol (79330-25G) were purchased from Sigma-Aldrich (St. Louis, MO, USA); 1,2,4-trihydroxybenzene, daidzin, piceid, rutin, and tangeretin were purchased from Tokyo Chemical Industry Co., Ltd. (Tokyo, Japan); 3,4-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, cyanidin, hesperetin, and sudachitin were purchased from FUJIFILM Wako Pure Chemical Corporation. Zerumbone was obtained from Adipogen Life Sciences (San Diego, CA, USA). Other phytochemicals were from natural compound libraries (S990043-NAT1/NAT2) purchased from Sigma-Aldrich (St. Louis, MO, USA).