Polylactic acid blends: an insight to their microbial production, biodegradation and applications

Biocomposites and blends from renewable materials have drawn the attention of many researchers worldwide driven by growing environmental concerns and the limited availability of fossil resources. Bio-based polylactic acid (PLA) polymers and their blends hold immense potential to serve as alternatives to current petroleum-based non-biodegradable polymers owing to their excellent properties, such as biocompatibility, biodegradability, high melting temperature, mechanical strength, ease of processing and antimicrobial properties. Consequently, these polymers exhibit great promise in industries such as food packaging, medical healthcare, agriculture and automobile. Lactic acid (LA), the primary component of PLA, can be produced by various microorganisms, including bacteria, fungi, and yeast. These microbes are often employed to synthesize LA from low-cost agro-industrial waste, reducing production expenses and fostering the development of sustainable biopolymers. To achieve effective purification of LA, several purification methods such as ion exchange chromatography (IEC), membrane filtration, distillation, precipitation and liquid–liquid extraction, have been used utilized. This review highlights recent advancements in the production, purification and biodegradation of bio-based PLA, while exploring the future potential of PLA blends as biodegradable bioplastics.