Relations between polyphenolics production and enzymatic antioxidant defense in Pulsatilla montana ssp. balcana in vitro
Wolfram, Evelyn (2015). Relations between polyphenolics production and enzymatic antioxidant defense in Pulsatilla montana ssp. balcana in vitro. Planta Medica, 81, 16. PW_04. Peer reviewed.; ; ; ;
Asian Pulsatilla species are utilized in traditional medicine as anti-inflammatory, spasmolytic, anti-enteritis and antitumor remedies. Little information is still available on the chemical composition and properties of the Balkan representatives of the genus.
Column and thin layer chromatographic separation of the methanolic extract of the aerials of Balkan endemic P. montana ssp. balcana led to isolation of miquelianin, caffeic and 3,5-dicaffeoylquinic acids as main components, which were determined by spectroscopic methods. In addition, tiliroside, hyperoside and isoquercitrin were confirmed by thin layer chromatography with authentic samples. Further on, shoot cultures of the plant were developed and treated with plant growth regulators in order to modify developmental patterns and study the enzymatic and non-enzymatic antioxidant defense of the plant in vitro. Indole-3-butyric acid stimulated the antioxidant enzymes phenylalanine ammonia-lyase, superoxide dismutase, catalase and glutathione peroxidase, but still increased oxidative stress (determined by the levels of hydrogen peroxide in vitro) and intensive callusogenesis were observed, worsening the quality of obtained explants. HPTLC screening showed reduced polyphenolics and DPPH scavenging capacity of these samples. On the contrary, 1-naphthaleneacetic acid led to inhibition of the activity of these enzymes, but stimulation of glutathione reductase and ascorbate peroxidase, as well as elevated non-enzymatic antioxidants as ascorbate and polyphenolics were observed, related to formation of normal rosette clumps and improved radical scavenging capacity of the plants. The results are indicative of the possible interrelations between enzymatic and non-enzymatic antioxidant defense in the plant which might be used as a tool for the optimization of polyphenolics production in vitro.