Polyhydroxyalkanoates (PHAs) are biodegradable polymers produced by microbes to overcome environmental stress. Commercial production of PHAs is limited by the high cost of production compared to conventional plastics. Another hindrance is the brittle nature and low strength of polyhydroxybutyrate (PHB), the most widely studied PHA. The needs are to produce PHAs, which have better elastomeric pr...

Polyhydroxyalkanoates (PHA) are biodegradable, thermoplastic polyesters produced from renewable carbon sources by a number of bacteria. However, their application is limited by high production costs. One of the strategies aimed to reduce their costs is the development of recombinant strains able to utilize different carbon sources. Many bacteria are naturally capable of accumulating biopolyeste...

The production of biodegradable plastic from microorganisms has great potential as a substitute for conventional plastic. This study aims to isolate bacterial strains capable polyhydroxyalkanoates (PHAs) the Kampung Jawa landfill land (KJLL) and characterize biopolymers. were able produce PHA using mineral salt medium (MSM) with glucose carbon source. qualitative screening PHA-producing bacteri...

The biosynthetic pathway of medium-chain-length (MCL) polyhydroxyalkanoates (PHAs) from fatty acids has been established in fadB mutant Escherichia coli strain by expressing the MCL-PHA synthase gene. However, the enzymes that are responsible for the generation of (R)-3-hydroxyacyl coenzyme A (R3HA-CoAs), the substrates for PHA synthase, have not been thoroughly elucidated. Escherichia coli Mao...

Medium-chain-length polyhydroxyalkanoates (PHAs) are polyesters having properties of biodegradable thermoplastics and elastomers that are naturally produced by a variety of pseudomonads. Saccharomyces cerevisiae was transformed with the Pseudomonas aeruginosa PHAC1 synthase modified for peroxisome targeting by the addition of the carboxyl 34 amino acids from the Brassica napus isocitrate lyase....

Polyhydroxyalkanoates (PHAs) can be divided into three main types based on the sizes of the monomers incorporated into the polymer. Short-chain-length (SCL) PHAs consist of monomer units of C3 to C5, medium-chain-length (MCL) PHAs consist of monomer units of C6 to C14, and SCL-MCL PHAs consist of monomers ranging in size from C4 to C14. Although previous studies using recombinant Escherichia co...

Sequencing batch reactor (SBR) systems were used for the development of a system and operating procedures for the high production and storage of polyhydroxyalkanoates (PHAs) by wastewater treatment (activated sludge) bacterial cultures. The systems were maintained at a nominal hydraulic retention time (HRT) of 10 hours, and a temperature of 20°C. The solids retention time (SRT) was maintained a...

Polyhydroxyalkanoates (PHAs) are microbial polyesters produced by various microorganisms. Many of these bacteria when fed with suitable carbon sources can produce PHAs up to about 30 wt% of the cell dry weight (CDW) and a few such as Ralstonia eutropha can accumulate PHAs up to almost 90 wt% of the CDW. In cyanobacteria (blue-green algae), the PHA content is usually about 5 wt% of the CDW. In t...

Together with other so-called "bio-plastics", Polyhydroxyalkanoates (PHAs) are expected to soon replace established polymers on the plastic market. As a prerequisite, optimized process design is needed to make PHAs attractive in terms of costs and quality. Nowadays, large-scale PHA production relies on discontinuous fed-batch cultivation in huge bioreactors. Such processes presuppose numerous s...

Agroindustrial by-products hold an enormous potential to be bioconverted into high-value-added products such as polyhydroxyalkanoates (PHA), a cost-effective alternative conventional plastics. In this study, cheese whey, highly abundant side stream of the making process, was explored feasible substrate for selection mixed culture enriched in PHA-storing bacteria using sequencing batch reactor u...