Polyhydroxyalkanoate Production from Bamboo Residues: Saccharification, Fermentation and Process Feasibility

Bamboo residues are a potential sugar source for polyhydroxyalkanoate (PHA) production, yet their suitability depends on the coupling of saccharification, microbial conversion and polymer recovery. This critical narrative review examined bamboo composition and pretreatment, direct PHA experiments and comparative evidence from other lignocellulosic feeds. It focused on enzymatic sugar hydrolysates, with lignin-rich pretreatment liquor considered separately. Bamboo studies demonstrated substantial tissue-dependent variation and production of concentrated glucose–xylose streams. Four related Halomonas studies established PHA production from selected bamboo-derived feeds, mainly in liquor-based, mixed-carbon or split-vessel configurations. Their results supported further sugar-hydrolysate development but did not validate a recovery-inclusive process across heterogeneous residues. Comparative experiments identified strain-specific pentose uptake, matrix tolerance and nutrient-dependent polymer accumulation as major selection criteria. Carbohydrate retention, conditioning losses and feeding strategy were more informative than maximum residual-solid digestibility alone. Recovery methods and selective cultivation introduced additional resource and product-quality trade-offs, while agricultural valorization of the separated liquor remained conditional. The central development need is to connect representative residue batches to sugar consumption, sustained PHA production and recovered material of specified quality. Economic and environmental assessments should use these linked measurements rather than isolated conversion maxima.