Construction of the highly secreted endochitinase Pichia pastoris strain and the optimization of chitin-degrading conditions

► The recombinant endochitinase Pichia pastoris was constructed. ► The time-course of the endochitinase expression was investigated. ► The optimal conditions of the powder chitin degradation were explored. ► The study lays a good foundation for the preparation of bioactive chitooligosaccharides in future.