Abstract
Succinic acid, a dicarboxylic platform chemical, serves as a highly versatile building block in the production of biodegradable plastics, pharmaceuticals, skincare products, cosmeceuticals, and food additives. Increasing global emphasis on sustainability has driven the growth of bio-based succinic acid from renewable resources as an alternative to conventional petrochemical routes. In this study, sugar polymers derived from oil palm lignocellulosic biomass particularly empty fruit bunches (EFB) was explored as sustainable feedstocks for succinic acid production. EFB are abundantly generated by the palm oil industry, are rich in polysaccharides yet remain underutilised, presenting significant potential for conversion into fermentable sugars and subsequently succinic acid. An efficient bioconversion process was developed, involving a pretreatment step utilising dilute ferric chloride to catalytically break down the complex lignocellulosic matrix, thereby enhancing the accessibility of their fermentable sugars. Optimisation of the pretreatment process was performed by varying reaction temperatures, metal chloride concentrations and reaction time to fractionate hemicellulose from the biomass and improve efficiency of enzymatic hydrolysis of the retained cellulose in the pretreated solids. Effective hemicellulose removal through dilute iron salt pretreatment significantly improved the enzymatic hydrolysis of EFB relative to untreated biomass. Bioproduction of succinic acid via fermentation of EFB hydrolysate using Actinobacillus succinogenes achieved a yield of 0.53 g/g and a productivity of 1.01 g/L·h. Among the downstream processing steps, the selection of an appropriate activated carbon was pivotal in achieving maximum decolourisation efficiency and enhancing the physical appearance of the purified product. This bioprocess is well suited for integration into a biorefinery approach for the cost-effective production of high-grade succinic acid and other bioproducts from oil palm biomass, contributing to Malaysia’s circular bioeconomy and sustainable development goals.
