Other lipase inhibitors have been recognized, e.g. from different plant products. These include alkaloids, carotenoids, glycosides, polyphenols, polysaccharides, saponins and terpenoids. However, none of these have been used clinically as lipase inhibitors. More active lipase inhibitors are the lipophilic compounds from microbial sources.
Lipase inhibitors from microbial source can be divided into two classes based on their structure. Those who have a β-lactone ring are lipstatin, valilactone, percyquinin, panclicin A-E, ebelactone A and B, vibralactone and esterastin. Those who do not have a β-lactone ring are (E)-4-amino styryl acetate, ε–polylysine and caulerpenyne.
Lipase inhibitors have also been made synthetically, e.g. cetilistat, based on the structure of triglycerides and other natural lipase substrates. However, the synthetic lipase inhibitors differ in structure and some of them lack the β-lactone ring.