The objective of this work is to apply metabolic algorithm to the various items involved during the software development process. The metabolic algorithm is introduced in the rewriting mechanism of membrane or P system considering many time varying functions. Rules for requirement evolution, reaction between items in the membrane, communications between data items, process speed-up and abort rule are being proposed. The metabolic algorithm is applied for the transformation of user requirements into system requirements which can be further segregated into functional as well as non-functional requirements. The requirement elicitation is illustrated and verified to obtain the most expected requirement objects using C# programming language.