Fully behind her after his initial doubts, he insisted that she complete her education after the death of her mother, rather than return home to care for her siblings.

[2] Mandel played a key role in clarifying the numerous components of the cellulase enzyme complex in moulds that had the ability to break down crystalline cellulose.

[1] In 1971 Mandels moved to the Bioengineering, Science and Advanced Technology Laboratory, and when Elwyn Reese retired in 1972 she became the head of this group.

[1][4] In the early 1970s the oil crisis prompted Mandels and her team to focus their research upon the possibilities of using cellulose as an energy resource.

It was essential to be able to measure cellulase activity, and Mandels developed an assay to predict the quantity of enzyme required.