Oil palm empty fruit bunch (EFB) fibres were pretreated by gamma irradiation followed by sodium carbonate (Na2
CO3
)
before the acid hydrolysis process to produce reducing sugars using diluted sulphuric acid (H2
SO4
). In this study, EFB
fibres were irradiated at different doses, i.e. 0, 100 and 200 kGy. Meanwhile, the gamma irradiated sample were then
subjected to Na2
CO3 pretreatment with 0 and 5% total titratable alkali (TTA). The effect of the pretreatment using gamma
irradiation and Na2
CO3
on the physical and chemical properties of the EFB fibres and the yield of the reducing sugar
obtained from the acid hydrolysis process was investigated. The obtained results showed that the content of holocellulose
was increased significantly with the increase of irradiation doses combined with Na2
CO3 pretreatment, whereas lignin
content of the EFB was decreased. The gamma irradiation and Na2
CO3 pretreatment resulted in structure breakage
and removal of silica of EFB fibres which can be due to the swelling of the fibres. A synergistic effect between gamma
irradiation and Na2
CO3 was observed, in which the yield of reducing sugars was increased by combining the gamma
irradiation and Na2
CO3 pretreatment.