| Sažetak | U ovom radu ispitan je učinak metanolnog ekstrakta žljezdastog nedirka (Impatiens glandulifera Royle, Balsaminaceae) na germinaciju sjemenki i parametre oksidacijskog stresa u klijancima bijele gorušice (Sinapis alba L., Brassicaceae). Sjemenke vrste S. alba tijekom tri dana bile su izložene metanolnom ekstraktu lista vrste I. glandulifera kojim je impregniran filtar papir u tri različite doze (1,5; 3 i 6 mL). U pokus je uključena negativna kontrola (filtar papir impregniran s deioniziranom vodom) i pozitivna kontrola (impregnacija s 0,02 M CuSO4). Pokusi su provedeni u triplikatu te je nakon 3-dnevne izloženosti odvagana masa svježeg tkiva klijanaca bijele gorušice. Homogenat biljnoga tkiva pripremljen je s trikloroctenom kiselinom (100 mg tkiva/0,5 mL TCA). U supernatantu je izmjeren sadržaj reduciranog glutationa (GSH), antocijanina i malondialdehida (MDA). Sadržaj GSH izmjeren je prema Ellmanu (Ellman, 1959), sadržaj antocijanina određen je pH-diferencijalnom metodom prema Giusti i Wrolstadu (2001), a sadržaj MDA pomoću tiobarbituratnog testa (Heath i Packer, 1968). Dobiveni rezultati obrađeni su statistički (t-test; P < 0,05).
Masa svježeg tkiva u svim tretiranim klijancima bijele gorušice je bila niža u odnosu na negativnu kontrolu. Sadržaj GSH u tretiranim klijancima vrste S. alba bio je viši u odnosu na negativnu kontrolu te je u uzorcima tretiranim sa 6 mL ekstrakta vrste I. glandulifera bio značajno viši od negativne kontrole (13,404 ± 0,716 μM vs. 10,365 ± 2,378 μM; P < 0,05). Tretman s ekstraktom vrste I. glandulifera uzrokovao je blagi rast u sadržaju antocijanina kod tretmana s 1,5 i 3 mL ekstrakta, iako je izloženost najvišoj dozi dovela do statistički značajno nižeg sadržaja antocijanina u odnosu na negativnu kontrolu (0,125 ± 0,035 mg/kg vs. 0,363 ± 0,042 mg/kg; P < 0,05). Sadržaj MDA u tretiranih klijanaca vrste S. alba nije se razlikovao od negativne kontrole. Dobiveni rezultati potvrđuju fitotoksičan učinak vrste I. glandulifera, a na temelju promjena u sadržaju GSH i antocijanina može se zaključiti da je u klijancima bijele gorušice ekstrakt I. glandulifera izazvao oksidacijski stres. |
| Sažetak (engleski) | In this thesis, the effect of methanol extract from himalayan balsam (Impatiens glandulifera Royle, Balsaminaceae) was tested on seed germination and oxidative stress parameters in white mustard seedlings (Sinapis alba L., Brassicaceae). Seeds of S. alba were exposed to methanol extract from I. glandulifera leaves (filter papers were impregnated with three different doses of methanol extract: 1.5; 3 and 6 mL) for three days. A negative control (filter paper impregnated with deionized water) and a positive control (impregnation with 0.02 M CuSO4) were included in the experiment. Experiments were performed in triplicate. After 3-day exposure, the fresh mass of white mustard seedlings was weighed. Plant tissue homogenate was prepared with trichloroacetic acid (100 mg tissue/0.5 mL TCA). Reduced glutathione (GSH), anthocyanin and malondialdehyde (MDA) content was assessed in the supernatant. The GSH content was measured according to the method of Ellman (Ellman, 1959). The anthocyanin content was determined by pH-differential method according to Giusti and Wrolstad (2001), while the MDA content was determined by using the thiobarbituric test (Heath and Packer, 1968). The obtained results were statistically analysed (t-test; P <0.05). The fresh mass weight of all treated white mustard seedlings was lower compared to the negative control. The GSH content in treated seedlings of S. alba was higher compared to the negative control, and in samples treated with 6 mL of extract of I. glandulifera it was significantly higher than the negative control (13.404 ± 0.716 μM vs. 10.365 ± 2.378 μM; P < 0.05). Treatment with extract of I. glandulifera (doses 1.5 and 3 mL) produced a slight increase in the anthocyanin content, although the exposure to the highest dose (6 mL) resulted in a statistically significantly lower anthocyanin content compared to the negative control (0.125 ± 0.035 mg/kg vs. 0.363 ± 0.042 mg/kg; P <0.05). The MDA content in treated seedlings of S. alba did not differ from the negative control. The obtained results confirm the phytotoxic effect of I. glandulifera, and moreover, based on changes in GSH and anthocyanin content it can be concluded that extract of I. glandulifera caused oxidative stress in white mustard seedlings. |
