STM Article Repository

The toxicity studies of the aqueous leaves extract of tobacco plant (Nicotiana tabacum) was investigated in human peripheral blood mononuclear cells (PBMC) using flow cytometer. To achieve this objective, variable doses of aqueous leaves extract (100 – 1000 µg) exposed to PBMC for 24 h incubation and also for 4 days to differentiate the monocyte population into macrophages with respect to forward scatter (shape and size) and side scatter (granularity of the cell). All these parameters were measured or observed through flow cytometer. The results showed that the aqueous leaves extract of tobacco plant (Nicotiana tabacum) significantly decline in monocyte, macrophage population or count and also declining in forward scatter and increased in side scatter at higher doses (1000 µg) as compared to control. In addition, the aqueous leaves extract of Nicotiana tabacum showed hemolytic activity at higher doses. Hepatitis B vaccine used as standard for these studies and the results showed that there is a significant increase in monocyte, macrophage, forward scatter and declining in side scatter as compared to control. Overall the results of aqueous leaves extract showed toxic effect at higher doses.