In‐Vitro Evaluation of the Antidiabetic Effects of Coffee as a Natural Inhibitor of Alpha‐Glucosidase

Diabetes mellitus is the seventh leading cause of death in the U.S., and affects over 29 million people. Type 1 diabetes, Type 2 diabetes, and gestational diabetes are the three prominent types. It is a progressive disease, often associated with numerous complications, including, but not limited to, retinopathy, neuropathy, and nephropathy. In 2012, the costs of diabetes exceeded 245 billion dollars. Oral hypoglycemic medications, insulin, and other injectable medications, have been widely used to control Type 2 diabetes, but have undesirable side effects and are expensive. Some agents control postprandial blood glucose levels through inhibition of α‐glucosidase, which delays the cleaving of polysaccharides, preventing the resulting monosaccharides from entering the blood stream. Examples of α‐glucosidase inhibitors are acarbose and miglitol. However, they both have undesirable side effects. Recent studies have pointed toward Phytotherapy, the use of medicinal plants or herbs which have little or no side effects, to treat hyperglycemia. This study investigates the hypoglycemic effects of coffee. Some studies have proposed that coffee may suppress postprandial hyperglycemia. We hypothesized that coffee reduces hyperglycemia by inhibiting alpha‐glucosidase activity. To determine this effect, serial dilutions of 200 mg/mL aqueous coffee extract was mixed with a 0.2 M phosphate buffer and 5 mM p‐Nitrophenyl α‐D‐glucopyranoside in a 96 well plate. The assay quantifying the α‐glucosidase inhibition activity of coffee was performed in‐vitro and measured using a spectrophotometer. Acarbose was used as the positive control of α‐glucosidase inhibition. The IC 50 was evaluated, as it is the concentration of the extract required to inhibit 50% of α‐glucosidase activity. From our observation, coffee extract did not inhibit alpha glucosidase at the doses used. More investigations are needed to optimize the approach in assaying the α‐glucosidase inhibition of coffee as well as identifying other mechanisms of action. Support or Funding Information Center of Excellence (COE) and BUILD program at Xavier University This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .