A Biochemical Study of α-Amylase Activity in Saliva of Some Libyan Cigarette Smokers

Abstract

Tobacco consumption alters many biological parameters, including α-amylase activity. This study reports the effect of cigarette smoking on salivary α-amylase activities of some male heavy smokers (100) in apparent good health compared with (40) male non-smokers as control. The salivary α-amylase activity was assayed using the standard colorimetric method. The α-amylase enzyme was characterized from the saliva samples collected from healthy adult smokers and non-smokers (control) to determine the effects of temperature, pH, and substrate concentration on the kinetic parameters of the enzyme. The analysis of the saliva samples showed that there were significant increases (P<0.05) in the α-amylase activity values in the saliva of cigarette smokers when compared with non-smokers at optimum conditions (2.74±0.37 nmol/min/mg-protein and 2.01±0.16 nmol/min/mg-protein, respectively). The Michaelis constant (Km) values of 0.5±0.02 mM and 1.12±0.08 mM observed for non-smokers and smokers were obtained from the double reciprocal plot of initial velocity (1/V) and substrate concentration (1/[S]). The maximum activities obtained at an optimum temperature of 37ºC, and an apparent pH of 7.0 for both subjects were 31.25±8.24 nmol/min/mg protein and 18.10±4.06 nmol/min/mg protein for non-smokers and smokers respectively. Measurements of salivary α-amylase activity could be useful in the early detection and diagnosis of parotitis. Subsequent studies are required to specify the mechanisms responsible for such a risk.