Abstract: The invention relates to enzymes, compositions, and methods for efficient hydrolysis of arabinans present in plant biomass. More specifically, the invention relates to arabinases and compositions comprising arabinases to improve cell wall degradation to efficiently use plant biomass for bio-energy production. The invention also relates to a method for preparing a prebiotic. The prebiotic may contain branched arabinan oligomers comprise ?-(1,5)-linked arabinan backbone, and single substituted ?-(1,3)-linked arabinose monomers attached to the backbone, or double substituted ?-(1,2,3,5)-linked arabinose monomers attached to the backbone, or both. The invention also relates to a method for preparing fruit juice or wine. The invention also relates to a method for saccharification of a plant biomass. The invention also relates to a recombinant micro-organism genetically modified to express the enzymes of the present invention and optionally additional enzymes to achieve the disclosed methods.