Poly(3-hydroxybutyrate)
(PHB)—a renewable and biodegradable
polymer—is a promising alternative to nonbiodegradable synthetic
plastics that are derived from petrochemicals. The methods currently
employed for PHB production are costly, in part, due to the expensive
cultivation feedstocks and the need to sterilize the culture medium,
which is energy-intensive. This study investigates the feasibility
of nonsterile PHB production from several saline organic wastes using
a salt-tolerant strain,
Zobellella denitrificans
ZD1 (referred to as strain ZD1). Factors such as the pH, salinity,
carbon/nitrogen (C/N) ratio, nitrogen source, and electron acceptor
that might affect the growth of strain ZD1 and its PHB production
were determined. Our results showed successful nonsterile PHB production
by growing the strain ZD1 on nonsterile synthetic crude glycerol,
high-strength saline wastewater, and real municipal wastewater-activated
sludge under saline conditions. The PHB production was significantly
enhanced when the levels of salts and nitrate-nitrogen in the culture
medium were increased. This study suggested a promising low-cost nonsterile
PHB production strategy from organic wastes using strain ZD1.