Specifically hydrolyzes the glucosidic linkage in glucosylceramide (PubMed:22072709). May prevent accumulation of aberrent glucosylceramide containing immature ceramide (By similarity). a beta-D-glucosyl-(1<->1')-N-acylsphing-4-enine + H2O = an N-acylsphing-4-enine + D-glucose Inhibited by metal cations Co(2+), Cu(2+), Ni(2+), Pb(2+) and Zn(2+) (PubMed:22072709). Not inhibited by metal chelator ethylenediaminetetraacetic acid (EDTA) (PubMed:22072709). Optimum pH is 7.5. Optimum temperature is 30 degrees Celsius. Belongs to the glycosyl hydrolase 5 (cellulase A) family.