Characterization and Biodegradation Evaluation of Biocapsules Composed of Polyester/Natural Product Composites

Abstract

ABSTRACTThe feasibility of using acrylic acid-grafted poly(hydroxyalkanoate) and a treated (cross-linked) natural product (treated marine algae powder) as a bacteria-encapsulated film capsule material was evaluated for the controlled release of an encapsulated bacterium. For the purposes of comparison and accurate characterization, a poly(hydroxyalkanoate) or acrylic acid-grafted poly(hydroxyalkanoate) and its composite film capsules were also assessed. The water resistance of acrylic acid-grafted poly(hydroxyalkanoate)/treated marine algae powder was greater than that of poly(hydroxyalkanoate)/marine algae powder, although the weight loss of composites buried in Azospirillum brasilense compost indicated that both were biodegradable, especially at high levels of marine algae powder or treated marine algae powder substitution. After 120 days, the weight loss of the acrylic acid-grafted poly(hydroxyalkanoate)/treated marine algae powder (20 wt%) composite was greater than 50%. Poly(hydroxyalkanoate)/marine algae powder exhibited a weight loss of approximately 3–12 wt% more than acrylic acid-grafted poly(hydroxyalkanoate)/treated marine algae powder. The bacterium completely degraded both the poly(hydroxyalkanoate) and acrylic acid-grafted poly(hydroxyalkanoate) and their composite film capsules, resulting in cell release. Based on the results of this work, the controlled release of bacteria-encapsulated film capsules for fertilizer utilization promotion appears achievable.