Safety evaluation of pigment containing Aspergillus carbonarius biomass in albino rats.

Aspergillus carbonarius, an ascomycetes fungus, is known to produce pectinase in solid-state fermentation. A mutant strain of A. carbonarius UV-10046 selected for temperature tolerance over produced polygalacturonase and during growth accumulated an yellow pigment in its biomass. Since the colored fungus suggested its application for food use, the freeze-dried biomass was evaluated to assess its safety in experimental animals. Acute and sub-acute toxicity studies were conducted on both sexes of albino rats. Feeding acute doses of A. carbonarius freeze-dried biomass at 0.5-5.0g/kg body weight to adult rats did not show any symptoms of toxicity or mortality of the rats. Similarly, dietary feeding of A. carbonarius at 0.25-2.0% level (w/w) for 14 weeks did not produce any significant changes in food intake or gain in body weight of the experimental rats compared to control rats. There were no significant differences in the relative weight of vital organs, hematological parameters, macroscopic and microscopic changes in vital organs and serum enzyme levels between the experimental and control groups. The results clearly showed that acute and sub-acute oral feeding of freeze-dried whole cells of A. carbonarius mutant for 14 weeks did not produce any toxic effects in male and female rats.

Acute and subchronic toxicity assessment of debitterized fenugreek powder in the mouse and rat.

Increased human use of fenugreek seeds (Trigonella foenum graecum) entails the generation of toxicity data in experimental animals. In this investigation, toxic effects of debitterized fenugreek (DFG) powder have been assessed following acute and subchronic regimens in mice and rats. In the acute study, DFG powder intragastrically administered to albino mice (CFT-Swiss, Mus musculus) and albino rats (CFT-Wistar, Rattus norvegicus) of both sexes failed to induce any signs of toxicity or mortality up to a maximum practical dosage of 2 and 5 g/kg body weight, respectively. Further, no significant alterations either in relative organ weights or their histology were discernible at terminal autopsy. In the 90-day subchronic study, DFG fed to weanling rats of both sexes at dietary doses of 0, 1, 5 and 10% in a pure diet had no effect either on the daily food intake or growth. Terminal autopsy revealed no alterations in relative organ weights of various vital organs, or their histoarchitecture. Haematological constants in DFG-fed rats were on par with those of controls. Further, biochemical measurements in serum and liver of DFG-fed rats revealed no appreciable changes in various parameters such as enzyme levels of GPT , GOT and ALP, as well as many serum constituents such as proteins, cholesterol, urea and creatinine at any of the dietary levels. From these results, it may be concluded that DFG does not produce any significant acute and cumulative toxicity at the doses administered, as reflected by the various parameters investigated.

Role of vitamin A in the haematotoxicity of hexachlorocyclohexane (HCH) in the rat.

The haematotoxicity of technical hexachlorocyclohexane (HCH) (1000 ppm) was investigated in male albino rats fed with diet free of vitamin A or containing vitamin A at 2000 or 10(5) I.U./kg. Assessment of HCH-induced haematotoxicity at the end of the 7 weeks feeding period was done on the basis of haemoglobin content, total count of red blood cells and white blood cells and the differential counts of the white blood cells as well as by parameters such as packed cell volume, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin content, prothrombin time and clotting time. In the rats fed with vitamin A-free diet containing HCH, significant reductions were noticed in the total white blood cells count, clotting time and prothrombin time indicating severe haematotoxicity. Differential count of the white blood cells of these rats revealed a non-significant reduction in the lymphocyte count. The only indication of haematotoxicity caused by hexachlorocyclohexane in the vitamin A supplemented rats was a slight but statistically significant reduction of the total count of white blood cells. These results demonstrate that the haematotoxicity of hexachlorocyclohexane in the rats is enhanced by vitamin A-deficiency and its supplementation particularly in excess but not at hypervitaminotic level is protective against the toxicity.

Cardiotoxic effects of dichlorvos (DDVP) in albino rats.

Dichlorvos (O, O-dimethyl O-(2,2-dichlorovinyl phosphate: DDVP 76.6 X EC) an organophosphate pesticide had a profound effect on cardiac activity of albino rats. Adult male rats anesthetized with pentobarbitone were administered 30, 50, 70 and 90 mg/kg body weight of dichlorvos. The heart rate and electrocardiogram were monitored and acetylcholinesterase activity was measured in heart and brain. Dichlorvos produced abnormalities in ECG, decrease in heart rate, cardiac arrest and inhibition of cholinesterase activity. It is suggested that cardiotoxic effect of DDVP may be mediated by the accumulated acetylcholine as a result of cholinesterase inhibition.