TOWARDS SUSTAINABLE BIOPLASTICS: A COMPARATIVE ANALYSIS OF POLYHYDROXYBUTYRATE (PHB) PRODUCTION BY ENTEROBACTER HORMAECHEI

Asritha R*, Husna Aara, Aleena Anjum, Prakruthi G and Dr. Siddalingeshwara K G

ABSTRACT

The polyhydroxy
alkanoates (PHAs) are a group of thermoplastic polyesters that possess properties such as
thermoplastic ch aracteristics and water resistance similar to the conventional plastics obtained from petrochemical
industries. Bacterial cells produce PHAs when essential nutrients such as nitrogen, phosphorous, iron, ammonium
or sulphate are limited, and excess carbon i s supplied. Due to its biodegradability and biocompatibility properties,
PHB holds significant potential for use in various areas such as pharmacological industries, environmental,
packaging, veterinary and industrial, agricultural, biomedical, molding pro ducts, paper coatings, adhesives, films,
and performance additives. In the current study, 13 bacterial strains were isolated from dump yard soil and
rhizosphere soil. Among these 3 bacterial strains showed maximum PHB production upon screening and were use d
for further studies. Out of three strains, Enterobacter hormaechei , produced the maximum PHB yield. The
maximum PHB production was obtained after an incubation period of 72 hrs. Optimization of environmental and
culture parameters were carried out wherei n the maximum PHB production was observed at a pH 7.0, temperature
35°, with 1.25% inoculum.. Effect of growth media on the production of PHB was studied, Luria bertani media was
found to be more suitable for the production PHB from Enterobacter hormaechei Maximum yield of 1.909% of
PHB yield was obtained in the current study. The yield can be further enhanced by using agricultural wastes and
industrial wastes as a source of carbon and nitrogen for large scale production.

Keywords: Poly hydroxyl butyrate ( PHB), Enterobacter hormaechei, Sudan black , PHB yield.