Conversion of shrimp heads to α-glucosidase inhibitors via co-culture of Bacillus mycoides TKU040 and Rhizobium sp. TKU041

Abstract

Alpha-glucosidase inhibitors (aGIs) have potential use as antidiabetic drugs for the treatment of type II diabetes. Most aGIs place a burden on the liver and cause gastrointestinal distress, therefore the development of new aGIs has become very important. In this study, we investigated the production of aGIs by the co-culture of Bacillus mycoides TKU040 and Rhizobium sp. TKU041 using shrimp head powder (SHP) as the sole source of carbon and nitrogen. After fermentation in 50 mL of 1% SHP-containing medium (0.1% K2HPO4 and 0.05% MgSO4·7H2O, pH 9.2) at 37 °C for 4 days, the maximum productivity of aGIs (143 U/mL) was reached. The IC50 of the aGIs produced in the culture supernatant was 3 mg/mL. The aGI activity was only 60% after treatment at pH 3 for 30 min; this increased to 140% after treatment at pH 11 for 30 min. The aGI activity remained at 60% after treatment at 60 °C for 30 min.