Alkaline phosphatase activity was assayed in Flexibacter chinensis to determine the effects of long term starvation stress and the effect of different nutrient amendments to starvation medium on the reactivation of this enzyme. Alkaline phosphatase activity increased at all temperature in starvation medium showing that reactivation could occur in cells previously grown in a high phosphate medium even under conditions where cell viability was declining, suggesting that in Flexibacter, de novo synthesis of enzyme occurs under starvation conditions. Addition of glucose and urea led to reactivation of alkaline phosphatase while the addition of inorganic phosphate had no effect on alkaline phosphatase activity. (c) 2006 Elsevier Inc. All rights reserved.