Evaluation of Macaranga tanarius as a biomass feedstock for fermentable sugars production

Macaranga tanarius is a fast-growing tree species that could be potentially utilized as a biomass feedstock for biorefinery. The average productivity of M. tanarius biomass was estimated to be ~19.2 ton/ha if the above-ground biomass is harvested bi-annually. Different pretreatment approaches were investigated to increase the enzymatic digestibility of foliage and woody biomass. The results indicated that no pretreatment was required for the foliage biomass while sequential acid/alkali pretreatment was necessary for the woody biomass before enzymatic hydrolysis. For the woody biomass, the delignification was 34.5% after sequential dilute acid/alkali pretreatment. The reducing sugar yields from enzymatic hydrolysis of foliage and pretreated woody biomass were 0.31 and 0.42 g/g dry biomass, respectively. The results also showed that both hydrolysates were fermentable by lactic acid bacteria. Overall, the results suggested that M. tanarius could be a potential feedstock for biorefinery based on the findings and processes derived from this study.