Screening and efficient production of engineered lipase B from Candida Antarctica for eco-friendly recycling of waste polycaprolactone

•Lipase B from Candida Antarctica was reported to depolymerize polycaprolactone.•We tried to screen and produce CalB variant with high PCL-depolymerizing activity.•PCL emulsion agar plate was used to screen CalB variant as a semiquantitative method.•CalB-658 exhibited the highest PCL-depolymerizing activity among the CalB variants.•CalB-658 was produced with high concentration using P. pastoris as a production host.