Methylobacteriumsp. ZP24 produced p

Methylobacteriumsp. ZP24 produced polyhydroxybutyrate (PHB) from disaccharides like lactose and sucrose. AsMethylobacterium
sp. ZP24 showed growth associated PHB production, an intermittent feeding strategy having lactose and ammonium sulfate at varying
concentration was used towards reaching higher yield of the polymer. About 1.5-fold increase in PHB production was obtained by this
intermittent feeding strategy. Further increase in PHB production by 0.8-fold could be achieved by limiting the dissolved oxygen (DO)
levels in the fermenter. The decreased DO is thought to increase flux of acetyl CO-A towards PHB accumulation over TCA cycle. Cheese
whey, a dairy waste product and being a rich source of utilizable sugar and other nutrients, when used in the bioreactor as a main substrate replacing the lactose, led to further increase in the PHB production by 2.5-fold. A total of 4.58-fold increase in the PHB production
was obtained using limiting DO conditions with processed cheese whey supplemented with ammonium sulfate in fed batch culture of
Methylobacteriumsp. ZP24. The present investigation therefore reflects on the possibility of developing a cheap biological route for production of green thermoplastics.