Abstract

The in vivo effects of varying concentrations of sodium benzoate (30, 60 and 120 mg/kg body weight) administered by gavage to male albino wistar rats (100 g average weight) over a 14-day period on the plasma levels of aspartate amino transferase and alkaline phosphatase were investigated. Thirty-six (36) male wistar albino rats (average weight of 100 g) were divided into four groups and housed in well-kept cages at the animal house. The rats were fed ad libitum on normal diets while the sodium benzoate solutions in water were given orally at 2-day intervals for 14 days. Blood samples were obtained from sacrificed animals at zero, 2-, 6- and 14-day and levels of plasma enzymes determined by standard methods. The results revealed that for aspartate amino transferase (AST), at 30 mg/kg, enzyme activity (IU/l) increased progressively from 27.33 ± 1.04 on the zero-day to 36.83 ± 1.25 on the 14^th day; at 60 mg/kg, the increase was to 38.50 + 0.50 on the 14^th day, while the enzyme level increased to 36.40 ± 0.96 on the 14^th day at 120 mg/kg of sodium benzoate. The increases were significant (p<0.05) relative to the control. For alkaline phosphatase (ALP), enzyme activity (IU/l) at 30 mg/kg increased from 114.83 ± 0.76 on the zero-day to 130.33 ± 1.04 on the 14^th day; at 60 mg/kg, the increase was to 130.16 ± 0.76 on the 14^th day, with an increase to 130.00 ± 0.40 noted on the 14^thday at 120 mg/kg sodium benzoate. The increase observed for ALP were significant (p<0.05). The findings suggest that short-term administration of sodium benzoate produce notable increases in serum levels of the two enzymes investigated.

Key words: Sodium benzoate, aspartate amino transferase, alkaline phosphatase.