Preventive effects of dill oil on potassium bromated-induced oxidative DNA damage in garlic root tips

In this study, the potential antimutagenic/cytoprotective effect of the oil extract (2.5µg/ml) from Anethum graveolens L. (Dill) on oxidative DNA damage was tested. The experiments were carried out to inhibit mutagenicity induced by potassium bromated (KBrO3-9g/l) in Allium assay using mitotic activities and nuclear DNA contents. Result showed a clear reduction in radical length in all KBrO3-treated groups compared to control plants. Mitotic activity, measured by mitotic index (MI) and mitotic stages, were significantly decreased in meristematic cells after KBrO3 application, The results showed that mitotic index (MI) was decreased to reach about 0.8 at 24 hrs compared with 23.9% in untreated plants. The analysis of potential cyto and genoprotective of dill extract on nuclear DNA contents showed a statistically significant increase in the nuclear DNA content compared to KBrO3-treated roots was observed. Clearly, dill oil showed highly performance in protecting the mitotic cells against mutagenic KBrO3 effects by increasing the MI and decreasing the abnormal chromosomes. Also, the percentage of damage reduction was observed in the pre- (28.9, 57.9 and 46.4 %), simultaneous (53.0, 70.6 and 35.7 %) and post- (37.3, 61.8 and 50 %) treatment. The results of the qualitative study showed that this dill extracts were rich in chemical compounds belonging to several phytochemical classes. GC-MS analysis detected 29 chemical compounds with different concentrations. The predominant ones were Octadecanoic acid (31.75%) and 2-pentanone, 4-hydroxy-4-methyl (16.77). So that these experiments will help to understand and uncover the mechanism of action dill oil against the mutagenic effects of KBrO3 (i.e whether they have a prophylactic or treatment activity).