Sakuranetin

Ethanol and sodium carbonate were purchased from Avantor Performance Materials Poland (Gliwice, Poland). Gallic, m-coumaric, o-coumaric, p-coumaric, caffeic, 5-O-caffeoylqunic, ferulic, isoferulic, vanillic, salicylic, 3-hydroxybenzoic, 4-hydroxybenzoic, protocatechuic, syringic, rosmarinic acid, quercitrin, apigenin 7-O-glucoside, eriocitrin, taxifolin, 3-O-methylquercetin, isorhamnetin, isorhamnetin-3-O-glucoside, luteolin, kaempferol, rutin, hyperoside, isoquercetin, sakuranetin, aluminum chloride, and LC–MS grade acetonitrile were purchased from Sigma-Aldrich Chemical Co. (St. Louis, Mo, USA). Folin–Ciocalteu reagent was supplied by Chempur (Piekary Śląskie, Poland). Quercetin was purchased from Fluka (Buchs, Switzerland). Catechin, naringenin 7-O-glucoside, eriodictyol, luteolin-7-O-glucoside, naringenin 7-O-glucoside, luteolin 3,7-diglucoside, nicotiflorin, narcissoside, gentisic, sinapic acid, and myricetin were provided by ChromaDex (Irvine, CA, USA). Astragalin, apigenin, naringenin, kaempferol-3-rutinoside, and tiliroside were supplied by Roth (Karlsruhe, Germany). LC–MS grade water was prepared using a Millipore Direct-Q3 purification system (Bedford, MA, USA).

The specific compounds, were: Caffeic acid, CAPE, chrysin, luteolin, daidzein, suberic acid, apigenin, (Alfa Aesar), pinocembrin, isorhamnetin, isosakuranetin, vitexin, orientin, rosmarinic acid, myricetin, vanillin, ursolic acid, hydroxytyrosol, tangeretin, chrysoeriol, betulinic acid, eriodictyol, sakuranetin, naringenin, t-cinnamic acid, genistein, diosmetin, resveratrol, galangin, pinocembrin 7-methyl ether, techtochrysin, (Extrasynthese) rutin, isoferulic acid, ellagic acid, kaempferol, quercetin, corosolic acid, acacetin, diosmin, protocatechuic acid ethyl ester, hesperetin, phloridzin, chlorogenic acid, p-coumaric acid, (±)catechin, maslinic acid, (Sigma Aldrich), rhamnetin, syringic acid, protocatechuic acid, ferulic acid, kaempferide, adipic acid, pinostrobin, gallic acid, pinobanksin (Fluka), naringin, hesperidin, (Acros Organics) pinobanksin-3O-acetate (Interchim Inc), cinnamylidenacetic acid, artepillin C (Wako Chemicals). o-Orselllinaldehyde was purchased from Santa Cruz Biotechnology (USA).
Water, acetonitrile, mEthanol and formic acid were purchased from Fisher Scientific, UK and they were of LC-MS grade. Ethanol was purchased from Merck, Germany. PTFE filters (0.45 μm) were obtained from Macherey-Nagel, Germany.

Analytical standards of apigetrin (apigenin 7-glucoside), chrysin, prunetin, rhamnazin, morin, isoquercetin, vitexin, isovitexin, quercitrin, kaempferitrin, taxifolin, luteolin, 3-O-methylquercetin, kaempferol, hyperoside, rutin, isorhamnetin, isokaempferide, rhamnetin, sakuranetin, luteoloside, eriodictyol-7-O-glucopyranoside, narirutin, naringin, LC grade acetonitryl, DMSO, DPPH radical, ampicillin, bovine serum, ferric chloride, hyaluronidase from bovine testes type I -S, sodium phosphate buffer pH 7, oleanolic acid, 2,4,6-tris(2-pyridyl)-s-triazine TPTZ, and hyaluronic acid were obtained from Sigma-Aldrich Fine Chemicals (St. Louis, MI, USA). Naringenin, astragalin, apigenin, tiliroside, and nicotiflorin were purchased from Roth (Karlsruhe, Germany). Dihydromyricetin was supplied by LGC (LGC Group, Teddington, UK), and laricitrin by Extrasynthese (Lyon, France). Quercetin was obtained from Fluka (Buchs, Switzerland). Catechin, luteolin-7-O-glucoside, luteolin 3,7-diglucoside, Naringenin 7-O-glucoside, eriodictyol, and myricetin were supplied by ChromaDex (Irvine, CA, USA). LC-MS grade water was prepared using a Millipore Direct-Q3 purification system (Bedford, MA, USA). Ethanol was obtained from Avantor Performance Materials (Gliwice, Poland).

Chemicals (2,2-diphenyl-1-picrylhydrazyl; 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid); 2,4,6-Tris(2-pyridyl)-s-triazine), reagents (Folin–Ciocalteu reagent), standards: caffeic acid, ferulic acid, benzoic acid, 4-hydroxybenzoic acid, p-coumaric acid, apigenin, sakuranetin, chrysin, naringenin, taxifolin, pinobanksin, pinocembrin were obtained from Sigma Aldrich (Saint Louis, MO, USA), and buffer components (chloroform, ethyl acetate, formic acid, ethanol, acetonitrile, formic acid) were purchased from Avantor Performance Materials Poland SA (APM, Gliwice, Poland).

Sakuranetin (1) was chemically synthesized from naringenin (2; Sigma-Aldrich, St. Louis, MO, USA) according to a previously reported method [16 (link)]. The Sakuranetin and naringenin used in this study were racemic mixtures. d-Xylose was purchased from Tokyo Chemical Industry (Tokyo, Japan). d-Ribose was purchased from Wako Pure Chemical Industries (Osaka, Japan). l-Arabinose was purchased from Nacalai Tesque (Kyoto, Japan). A Sylon BFT kit (BSTFA + TMCS, 99:1; Supelco, Bellefonte, PA, USA) was used for trimethylsilylation.

All the used chemicals were of analytical grade. Standard of homogentistic, acid (±)-2-cis, 4-trans-abscisic acid, kurarinone, sakuranetin, and quinine sulphate were purchased from Sigma–Aldrich (Milan, Italy). (±)-2-trans, 4-trans-abscisic acid was purchased from A.G. Scientific, Inc (San Diego, CA, USA). Unedone was purchased from Chem Faces Biochemical Co., Ltd. (Wuhan, China). Methanol, acetonitrile, phosphoric acid 85% w/w, and absolute ethanol were obtained from Sigma–Aldrich (Milan, Italy). acetonitrile, water, and formic acid of LC-MS grade were purchased from Merck (Darmstadt, Germany). Ultrapure water (18 MΩ cm) was obtained with Milli-Q Advantage A10 System apparatus (Millipore, Milan, Italy).

Cells were seeded in quadruplicate in 96-well plates and stimulated for 24 h at increasing concentrations of sakuranetin (Sigma, St. Louis, MO, USA). Cell viability was determined using the MTS (3-(4,5-dimethylthiazol-2-yl)-5-3(carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) reduction method (CellTiter 96 One Solution Cell Proliferation Assay Kit, Promega, Madison, WI, USA), based on the measurement of mitochondrial respiration in living cells. Optical density was measured at 490 nm with a microplate reader (Molecular Devices, Sunnyvale, CA, USA).