2 5 dihydroxybenzoic acid

Bleomycin, carboxymethylcellulose sodium and 2,5-dihydroxybenzoic acid were purchased from Merck KGaA (Darmstadt, Germany), and LC-MS-grade methanol and water were purchased from VVW (Søborg, Denmark).

Chemical structures of the investigated analytes are presented in the Supplementary Material (Fig. S1) and both theoretical and empirically determined mass-to-charge (m/z) values of the molecular species used in the study are provided in Table S1. The AChE inhibitor tacrine and 9-aminoacridine (9AA) were purchased from Sigma-Aldrich (Stockholm, Sweden), while the deuterated analogues ACh-d₉, ACh-d₄ and CHCA-d₄ were obtained from CDN isotopes (Essex, UK), BOC Sciences (NY, USA), and Ubichem (Budapest, Hungary), respectively. The solvents water, methanol and acetonitrile were of HPLC grade (VWR, Stockholm, Sweden). Trifluoroacetic acid (TFA) and 2,5-dihydroxybenzoic acid (DHB) were purchased from Merck (Darmstadt, Germany).

All solvents and reagents for syntheses were
obtained from common commercial sources (Merck, Germany; Fluorochem,
UK; Penta Chemicals, Czech Republic) and used without further purification.
β-Cyclodextrin was purchased from Waco Chemicals (Germany).
Water (HPLC LC-MS grade, VWR Chemicals, USA) and 2,5-dihydroxybenzoic
acid (Merck, Czech Republic) were used for mass spectrometric analysis
without further purification.

Analytical-grade salts, buffer reagents, chloramine T, hydrochloric acid (HCl), acetic acid (CH₃COOH), potassium iodide (KI), methanesulfonic acid (CH₄O₃S), adrenaline, glutathione reductase (GR), peroxidase, and ethylenediaminetetraacetic acid (EDTA) were purchased from Sigma-Aldrich, St. Louis, MO, USA. 3,3′,5,5′-tetramethylbenzidine (TMB), nicotine adenine dinucleotide phosphate (NADPH), L glutathione reduced (GSH), and oxidized (GSSG) were from SERVA Electrophoresis GmbH, Heidelberg, Germany. Hydrogen peroxide (H₂O₂), methanol, and 2,5-dihydroxybenzoic acid (DHB) were provided by Merck KGaA, Darmstadt, Germany. 5,5′-dithio-bis-2-nitrobenzoic acid (DTNB) was purchased from Acros Organics, Geel, Belgium, while 1-methyl-2-phenylindole (MFI) and uric acid were from Alfa Aesar, Ward Hill, MA, USA. Dimethyl sulfoxide (DMSO), chloroform, and acetonitrile (C₂H₃N) were from Fisher Scientific, Waltham, MA, USA.

Fmoc-L-phenylalanine, Fmoc-L-glutamic acid 5-tert-butyl ester, and N-α-Fmoc-N-ß-trityl-L-asparagine were procured from Fluka (Buchs, Switzerland), while Fmoc-O-tert-butyl-L-tyrosine was sourced from Roth (Karlsruhe, Germany). Furthermore, Rink amide resin (4-(2′,4′-dimethoxyphenyl-Fmoc-aminomethyl)phenoxy resin, PEPTIPURE^®, 100–200 mesh, 0.3–0.8 mmol·g⁻¹, 1% DVB) purchased also from Roth was used as a solid support. Various chemical reagents essential for experimental procedures were obtained from reputable suppliers. Dimethyl sulfoxide (DMSO, EMSURE ACS), diethyl ether (EMSURE ACS), N,N-dimethylformamide (DMF), piperidine (PYP), triisopropylsilane (TIS), acetic acid, benzotriazol-1-yl-oxytripyrrolidino phosphonium hexafluorophosphate (PyBOP), N-methylmorpholine (NMM), 2,5-dihydroxybenzoic acid (DHB), α-cyano-4-hydroxycinnamic acid (HCCA), and NaH₂PO₄ were acquired from Merck (Darmstadt, Germany). Dichloromethane (DCM) was sourced from Scharlab (Barcelona, Spain), while methanol, acetonitrile (ACN, HPLC grade), and trifluoroacetic acid (TFA) were obtained from Carl Roth (Karlsruhe, Germany). All solutions were prepared meticulously using water of high purity with a resistivity of 18.2 MΩ∙cm, generated through a Millipore Milli-Q system (Bedford, MA, USA).

All. vitis strains were phenotypically characterized using API and Biolog tests. The API 20NE kit was used according to manufacturer’s instructions (bioMérieux, France). Utilization of sole carbon sources was tested with Biolog GEN III microplates using protocol A, according to the instructions of the manufacturer (Biolog, Inc., USA).
The metabolism of 4-hydroxyphenylacetic acid (p-hydroxyphenylacetic acid; Acros Organics, Product code: 121,710,250) and gentisic acid (2,5-dihydroxybenzoic acid; Merck, Product Number: 841745) was performed in AT minimal medium [90 (link), 91 (link)] supplemented with yeast extract (0.1 g/L), bromthymol blue (2.5 ml/L of 1% [w/v] solution made in 50% ethanol), and the tested compound (1 g/L). Hydroxyphenylacetic and gentisic acids were added as filter-sterilized 1% aqueous solutions. Bacterial growth and color change of the medium were monitored during one week of incubation at 28 °C and constant shaking (200 rpm/min). Metabolism of L( +)-tartaric acid, involving production of alkali from this compound, was tested as described before [5 ].