2 2 di 4 tert octylphenyl 1 picrylhydrazyl dpph

Reagents of Mass Spectrometry grade, including acetonitrile, methanol, water, and formic acid, were purchased from Sigma Chemical Co. (St. Louis, MO, USA). Also, Folin–Ciocalteu’s phenol reagent was obtained from Sigma Chemical Co. Analyzed phenols included protocatechuic acid, m-hydroxybenzoic acid, chlorogenic acid, salicylic acid, caffeic acid, syringic acid, sinapic acid, ferulic acid, p-coumaric acid, m-coumaric acid, o-coumaric acid, gallic acid, o-hydroxybenzoic acid, 3,4-dihydroxyphenylacetic acid, trans-cinnamic acid, vanillic acid, benzoic acid, ellagic acid, vitexin, rutin, (+)-catechin, apigenin, kaempferol, orientin, naringenin, myricetin, isorhamnetin-3-O-rutinoside, isorhamnetin-3-O-glucoside, kaempferol-3-O-rutinoside, quercetin, and its derivativeswere purchased from Sigma Chemical Co. (St. Louis, MO, USA). Folin–Ciocalteu’s phenol reagent, 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), 2,2-di(4-tert-octylphenyl)-1-picrylhydrazyl (DPPH), and 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox) were obtained from Sigma Chemical Co. (St. Louis, MO, USA).

Polyvinyl chloride S-61 (PVC) was purchased from Anwil S.A. (Poland). A thermal stabiliser, Reagens CLX/743, was purchased from Reagens S.P.A. (Italy). A plasticizer (ES), an epoxidized soybean oil, was purchased from Boryszew—Erg S.A. (Poland). Cassia oil (CO) and 2,2-Di(4-tert-octylphenyl)-1-picrylhydrazyl (DPPH*) were purchased from Sigma-Aldrich (Germany/USA). Ethanol (96%) and methanol were purchased from Avantor S.A. (Poland). All the chemicals were of an analytical grade. Demineralized water was used for all these experiments.
The microorganisms used in the research came from the collection at the Universität Hohenheim Institut für Umwelt- und Tierhygiene sowie Tiermedizin mit Tierklinik and the collection of pure cultures from the Department of Microbiology and Food Technology at the Bydgoszcz University of Science and Technology. In studies on the impact of the bacteriostatic properties of cassia oil, the following bacterial species were tested: Listeria monocytogenes and Enterococcus faecalis. The media used in the microbiological tests were enriched broth (Merck 07882) and nutrient agar (Merck 107881) purchased from Merck (Germany).