ABSTRACT
Polyhydroxyalkanoates are polyesters of hydroxyalkanoates synthesized by many bacteria and haloarchaea as carbon and energy storage materials. There are more than 150 types of polyhydroxyalkanoate monomers reported, resulting in a variety of Polyhydroxyalkanoates with diverse properties. The material variability, nonlinear optical properties, piezoelectric properties, gas barrier properties, thermoplasticity, biodegradability, and biocompatibility allow polyhydroxyalkanoates to be used for plastic packaging, chiral chemicals generation, medicine, agriculture and bio-energy fields. This review introduces the current applications and future development of polyhydroxyalkanoates.
ABSTRACT
Microbial polyhydroxyalkanoates (PHA) has developed with more diversity and more advanced manufacturing technology. Diversity has now been reflected by diverse monomers, diverse structures and diverse polymerization modes, giving the concept of "PHAome". In addition, the application of synthetic biology and the development of seawater-based biotechnology reduce the production cost of PHA, making PHA more economically competitive. Some examples of commercialized PHA products are described here. Besides, PHA with high value added applications has been exploited.
Subject(s)
Biotechnology , Polyhydroxyalkanoates , Chemistry , Synthetic BiologyABSTRACT
Polyhydroxyalkanoates (PHAs), as a novel class of biopolymer, are attracting more attention due to their diverse material properties and environment-independent biodegradability. Here we report the preparation of PHA exhibiting efficient antibacterial activity by embedding Nisin, a food additive generally recognized as safe, into poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx), a type of PHA with high biocompatibility. We first prepared Nisin-containing PHBHHx films using solvent casting method. Confocal laser scanning microscopy analysis showed that a well-mixed integrated structure of the films with an even distribution of the Nisin particles in the PHBHHx matrices. Then the antimicrobial activity of PHBHHx/Nisin films against Micrococcus luteus was quantified on agar plate by measuring the size of inhibition zone. Cultivation in liquid media further confirmed the releasing of Nisin from the films and the long-time antibacterial activity. Results showed that the threshold of Nisin concentration for long-time and effective inhibition against bacteria growth is 25 μg/g. These results altogether establish a technological foundation for the application of PHA in biomedicine and food industry.