Influence of decoction of seeds of Cassia tora Linn (Leguminosae) on the genotoxicity of sodium azide and acetaminophen in Allium cepa model
M Singh, P Solanke, H Rathore, A Sharma, M Makwana, S Shrivastava
genotoxicity, sodium azide and acetaminophen
M Singh, P Solanke, H Rathore, A Sharma, M Makwana, S Shrivastava. Influence of decoction of seeds of Cassia tora Linn (Leguminosae) on the genotoxicity of sodium azide and acetaminophen in Allium cepa model. The Internet Journal of Toxicology. 2008 Volume 6 Number 1.
During the first experiment
The seeds of a medicinal plant
Materials And Methods
Dry healthy onions of almost same size i.e. 1.5 to 2.0 cm in diameter were obtained from local market and brought to the laboratory.
Dried seeds of the medicinal plant
Sodium azide (NaN3) sodium azide 99% pure salt (NaN3 MW 65.01) made by Central Drug House, New Delhi, India was used. NaN3 was dissolved in tap water and diluted to obtain concentrations ranging from 0.31 mg/L to 10 mg/L (ppm).
Acetaminophen (paracetamol) under trade name medimol dispersible 500 mg B.P. tablets is made by Synchem. Laboratories, Baroda (Gujrat) were dissolved in known amount of luke warm tap water to prepare stable suspensions of desired concentrations (as clear solution can not be obtained).
Studies of the cultivation of 24 hr grown
Group-I 12 bulbs in tap water, controls, Group-II 12 bulbs in each of six concentrations of sodium azide (0.31, 0.62, 1.25, 2.5, 5 and 10 ppm) Group-III 12 bulbs in each of six different concentration of sodium azide as in earlier group but each concentration level of sodium azide also aqueous decoction of
All three groups of
Cultivation of 24 hr grown
All three groups of
Staining, Squashing And Observation of Slides
Root tips were squashed using N-HCl-2% acetocarmine stain. Four fields from each slide were observed to cover 50 cells i.e. total 200 cells per slide, 3000 to 4000 cells were observed for each group of onion. Mitotic index was calculated as number of dividing cells per 100 observed cells.
Slides were also observed to determine incidence of mitotic arrest, chromosome fragmentation, abnormal orientation, lagging chromosomes and polyploidy etc.
All experiments were conducted in triplicate. A Student 't' test was applied at a 5% level of significance.
Influence of NaN3 alone or in combination with
Mean Root Length (MRL, Table-1)
In controls, 24 hr grown roots grew further throughout the tenure of experimentation (Group-I). However, sodium azide exposures caused significant inhibition of root growth at all test concentrations (Group-II), which could be checked by
Morphology - Colour And Shape of Root Tips (Table-2)
In controls (Gr-I), no change in the morphology of tips occurred. NaN3 exposure (Gr-II) caused 'bulb' like swelling of root tips at highest three concentrations tested but did not caused a change in the colour at any concentration. NaN3 plus C.tora seed decoction (at fixed concentration) exposure (Gr-III),
changed colour of roots pale at initial four concentrations and dark pale at higher two concentrations. NaN3 could not induced 'bulb' like tips at a 2.5 mg/l concentration in the presence of C.tora, however, at higher (5mg/l and 10mg/l) concentrations 'bulb' formation could not be prevented even in the presence of C.tora seed decoction.
Mitotic Index (MI, Table-3)
Sodium azide declined mitotic index at all six concentrations. In the presence of C.tora seed decoction sodium azide induced depressed mitosis could be prevented at initial two concentrations.
Chromosomal Aberrations (Table-4)
No chromosomal aberrations or abnormal mitosis could be observed in controls (Gr-I) but sodium azide exposure caused a scattering of chromosomes at metaphase (disturbed metaphase arrangement) in a dose dependent manner (Gr-II). In the presence of C.tora seed decoction (Gr-III) sodium azide induced scattering of chromosomes at metaphase could be fully prevented at the initial two concentrations (0.31 mg/l and 0.62 mg/l) tested but were found significantly less pronounced at 1.25 mg/l and at 2.5 mg/l and it could not be remedied at higher i.e. 5 mg/l and 10 mg/l concentration levels.
In Gr-III each concentration at NaN3 had
a = Control Vs all group, b = Gr-II Vs Gr-III at each concentration level., SC = Sticky chsomosome, STC = Scattered chsomosome
MPA = Multipolar anaphase CB = Chromosome bridge LC = Lagging chromosome
MNC = Micronucleated cells PKC = Polykaryotytes
Influence of paracetamol alone or in combination with
Mean Root Length (MRL, Table-5)
Acetaminophen exposure (Gr-II) caused significant inhibition of root growth. Even in the presence of C.tora seed decoction paracetamol inhibited root growth (Gr-III) but inhibition is significantly less pronounced in comparison to acetaminophen alone (Gr-II).
Morphology - Colour And Shape of Root Tips
No changes in the shape and colour of root tips could be noticed in any group of onions.
Mitotic Index (MI, Table-6)
In controls (Gr-I) mean value of mitotic index did not change significantly during experimentation but acetaminophen exposure (Gr-II) declined mitotic index significantly. Presence of C.tora seed decoction could significantly check acetaminophen induced depressed mitosis (Gr-III).
Abnormal mitosis or any sort of chromosomal aberrations could not be observed in any group.
Sodium azide exposure lowered mitosis, disturbed metaphase stage and induced bulb like swelling of the tips of roots but acetaminophen exposure reduced only the process of mitosis. Neither azide nor acetaminophen induced chromosomal aberrations.
Genotoxicity of sodium azide has been established in three common plant protocols namely
The results of the present study did not show chromosomal aberrations. It seems that differences in purity of chemical used, physicochemical properties of tap water and laboratory conditions might have been responsible for this discrepancy.
It is, therefore, concluded that
Authors thank Prof. Dr. D. Amritphale for identification of
Prof. Dr. H.S. Rathore School of Studies in Zoology and Biotecnology Vikram University, Ujjain, India. Email : firstname.lastname@example.org