by suitable choice of composition and processing conditions,
polymer can often be tailor-made to have specific and desirable properties. Aulosira
fertilissima CCC 444 when cultivated in a mixture of fructose and valerate produced
poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] co-polymer up to 537.5
mg l−1 containing 25 mol% 3HV monomers. Manipulation of the culture conditions
such as varying pH, temperature, initial cell concentrations and dark incubation
significantly affected the accumulation as well as composition of P(3HB-co-3HV)
copolymer; therefore, the polymer finds a wider application. The molar fraction of 3HV
tended to increase up to 35 mol% in the early phase of A. fertlissima cultivation, i.e. on
7th day. An initial inoculum size of 80 mg dcw l-1 was found optimum for P(3HB-co-
3HV) copolymer accumulation. Lower temperature conditions favoured the
accumulation of copolymers containing higher molar fractions of 3HV monomers as
compared to high temperature conditions. It was also observed that 3HV molar
fractions in the co-polymer can tailored up to 50 mol% by maintaining the pH of culture
medium at 9.5, without significantly affecting the copolymer content (72% dry cell
weight). This opens up new possibilities of using A. fertilissima as a suitable feedstock
for production of P(3HB-co-3HV) co-polymer with varied 3HB and 3HV fractions for
various industrial and pharmaceutical applications.