The changes of the antioxidant (AOA) and antiradical activities (ARA) and the total contents of phenolics, anthocyanins, flavonols, and hydroxybenzoic acid in roots and different aerial sections of Echinacea purpurea, nettle, and dandelion, after treatment with ornithine decarboxylase inhibitor, a polyamine inhibitor (O-phosphoethanolamine, KF), and a phenol biosynthesis stimulator (carboxymethyl chitin glucan, CCHG) were analyzed spectrophotometrically; hydroxycinnamic acids content was analyzed by RP-HPLC with UV detection. Both regulators increased the AOA measured as inhibition of peroxidation (IP) in all herb sections, with the exception of Echinacea stems after treatment with KF. In root tissues IP was dramatically elevated mainly after CCHG application: 8.5-fold in Echinacea, 4.14-fold in nettle, and 2.08-fold in dandelion. ARA decrease of Echinacea leaves treated with regulators was in direct relation only with cichoric acid and caftaric acid contents. Both regulators uphold the formation of cinnamic acid conjugates, the most expressive being that of cichoric acid after treatment with CCHG in Echinacea roots from 2.71 to 20.92 mg g(-1). There was a strong relationship between increase of the total phenolics in all sections of Echinacea, as well as in the studied sections of dandelion, and the anthocyanin content.

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A noncombustible tough poly(vinyl chloride) (tPVC) was prepared by suspension-grafted copolymerization of poly(2-ethylhexyl acrylate) (poly-EHA; elastomer) with vinyl chloride (VC). Elastomer (poly-EHA) was prepared by emulsion, mainly homopolymerization of 2-ethylhexyl acrylate at a temperature of 30 Ϯ 0.1°C in the presence of a redox system and with the advantage of dosing the monomer into two portions. Grafted-suspension copolymerization of poly-EHA with VC was carried out at 54 Ϯ 0.1°C, keeping other reaction conditions only slightly modified in comparison with those for the polymerization of pure VC. An optimum content of the incorporated poly-EHA in PVC was found to be in the range 7.5-8.5 wt %, whereas notched toughness of 85-87 kJ m Ϫ2 was reached. Both below and above the found range of the content of poly-EHA, the toughness decreases. A copolymer prepared by a directemulsion copolymerization of 2-EHA and VC (poly-EHA-co-VC) exhibited worse mechanical properties than the copolymer prepared by two polymerization steps. On the basis of experimental results, effects of the reaction procedure on the properties of resulting material are described. In addition to good mechanical properties, tPVC also shows its noncombustibly.