Mannan endo-1,6-ñ-mannosidase (, exo-1,6-ò-mannanase, endo-ñ-1âÂÂ6-<small>D</small>-mannanase, endo-1,6-ò-mannanase, mannan endo-1,6-ò-mannosidase, 1,6-ñ-<small>D</small>-mannan mannanohydrolase) is an enzyme with systematic name 6-ñ-<small>D</small>-mannan mannanohydrolase. It catalyses the random hydrolysis of (1âÂÂ6)-ñ-<small>D</small>-mannosidic linkages in unbranched (1âÂÂ6)-mannans