Activating antioxidant enzymes, hyoscyamine and scopolamine biosynthesis of Hyoscyamus niger L. plants with nano-sized titanium dioxide and bulk application | Aktiviranje aktivnosti antioksidacijskih encimov, biosinteze hiosciamina in skopolamina pri črnem zobniku (Hyoscyamus niger L.) z nano in celokupnimi delci titanovega dioksida

anglais. Application of nanotechnology is now widely distributed overall the life, especially in agricultural systems. This study intended to indicate the impacts of nano-sized titanium dioxide particles (NT) and bulk (BT) on antioxidant enzymes activities including superoxide dismutase (SOD), peroxidase (POX) and catalase (CAT), and variations of two major tropane alkaloids such as hyoscyamine (HYO) and scopolamine (SCO) in Hyoscyamus niger L. Plants were treated with different concentrations of NT and BT (0, 20, 40 and 80 mg l-1). Alkaloids extracted were identified by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) analysis. Results showed that SOD activity increased with increasing titanium dioxide concentration in both nano-particles and bulk treated plants. However, the highest and the lowest POX activity were observed in plants exposed to NT at 40 mg l-1 and control, respectively. Generally, all tested enzymes activities were higher in NT treated plants that those of BT except CAT activity at 80 mg l-1. The highest alkaloids content values, HYO: 0.286 g kg-1 and SCO: 0.126 g kg-1, were achieved in plants treated with NT at 80 and 20 mg l-1, respectively. The maximum and minimum plant biomass and subsequently total alkaloids yield were obtained in plants exposed to NT at 40 mg l-1 and controls, respectively. Our results suggest that NT in appropriate level (40 mg l-1) may act as an elicitor for biochemical responses and tropane alkaloids biosynthesis in H. niger plants.

slovène. Uporaba nanotehnologije je v svetu danes zelo razširjena v znanostih o življenju, še posebej v kmetijstvu. V raziskavi je bil preučevan vpliv nano delcev (NT) in celukopnih delcev (BT) titanovega dioksida na antioksidacijsko aktivnost encimov kot so superoksid dismutaza (SOD), peroksidaza (POX) in katalaza (CAT) in vpliv tega obravnavanja na variabilnost vsebnosti dveh glavnih tropanskih alkaloidov, hiosciamina (HYO) in skopolamina (SCO) v črnem zobniku (Hyoscyamus niger L.). Rastline so bile tretirane z naslednjimi koncentracijami NT in BT delcev: 0, 20, 40 and 80 mg l-1. Ekstrahirani alkaloidi so bili analizirani in določeni s plinsko kromatografijo (GC) in plinsko kromatografijo povezano z masno spektroskopijo (GC-MS). Rezultati so pokazali, da se je aktivnost SOD povečala pri tretmajih z NT in BT delci z naraščanjem njihove koncentracije. Aktivnost POX pa je bila največja pri rastlinah izpostavljenih NT delcem pri 40 mg l-1 in najmanjša pri kontroli. Nasplošno so bile aktivnosti vseh testiranih encimov večje pri rastlinah tretiranih z NT delci kot pri tretmaju z BT delci, razen aktivnosti CAT pri tretmaju z 80 mg l-1. Največji vsebnosti alkaloidov, HYO: 0.286 g kg-1 in SCO: 0.126 g kg-1, sta bili doseženi pri rastlinah tretiranih z NT delci pri koncentracijah 80 in 20 mg l-1. Največja biomasa in največji pridelek alkaloidov sta bila dosežena pri rastlinah tretiranih z NT pri 40 mg l-1 in najmanjša pri kontroli. Rezultati kažejo, da NT delci v primernih koncentracijah (40 mg l-1) delujejo kot elicitorji za biokemične odzive in biosintezo tropanskih alkaloidov pri črnem zobniku.