Low-molecular-weight chromium-binding substance (LMWCr) also named chromodulin has been shown to bind to the insulin receptor in response to insulin and increase the ability of insulin to signal cells when glucose concentrations in the blood are high. This material may be related to adult-onset diabetes, where body tissues become insensitive to insulin. Our laboratory has used liver from the common brown octopus, octopus vulgaris and an in vitro chromium loading procedure to isolate LMWCr. The results of the isolation procedure, spectroscopic characterization, biological activity, and a comparison with other chromodulins will be presented.