All the variables considered in this study, viz. concentrations of acetate, glucose and valerate with incubation period contributed significantly to the accumulation of P(3HB-co-3HV) copolymer in N. muscorum Agardh. P(3HB-co-3HV) copolymer biosynthesis requires 3-hydroxybutyryl-CoA (3HB-CoA) and 3-hydroxyvaleryl-CoA (3HVCoA) as substrates for the polymerization reaction catalyzed by the enzyme, PHA synthase