The enzyme lipase is excreted out of the cells (an exoenzyme) into the surrounding media, catalyzing the breakdown of tributyrin, a vegetable oil, into fatty acids which can then be taken up by the or...The enzyme lipase is excreted out of the cells (an exoenzyme) into the surrounding media, catalyzing the breakdown of tributyrin, a vegetable oil, into fatty acids which can then be taken up by the organism. This reaction causes the agar, normally a light blue opaque color to clear around the growth area.
