Chemical Composition, Biochemical Activity of Black Rice Yeast Extract, and Their Potential as Anti-diabetic


  • Rudiana Agustini Department of Chemistry, Universitas Negeri Surabaya, 60231, Indonesia
  • I G. M. Sanjaya Department of Chemistry, Universitas Negeri Surabaya, 60231, Indonesia
  • N. Herdyastuti Department of Chemistry, Universitas Negeri Surabaya, 60231, Indonesia
  • A. Sabarudin Department of Chemistry, Brawijaya University, 65145, Indonesia


α–amylase inhibitor, antioxidant, biochemical, extract of black rice yeast, antidiabetic


Background: Metabolic disorders are characterized by high glucose levels (diabetes mellitus/DM) and have a very high prevalence, globally. Utilization of natural ingredients having anti-diabetic potential is one solution to these disorders. The purpose of this research was to study the chemical and biochemical content of black rice yeast extract and its potential as an anti-diabetic by analyzing its activity as an α–amylase inhibitor. Materials and Methods: First, maceration technique was used with distilled water as a solvent to produce black rice yeast extract (BRY-E). This was followed by profiling of chemical components of BRY-E and antioxidant activity test using 2,2-diphenyl-1-pikrilhidrazil (DPPH method). Finally, α–amylase inhibition value was determined. Results: Total 55 compounds were identified in black rice yeast extract using the liquid chromatography–mass spectrometry (LC-MS). These included flavonoids, phenolics, antioxidants and other components. The IC50 of BRY-E or inhibition concentration that can dampen 50% of free radicals was found to be 150µg/ml. The IC50 of BRY-E as α–amylase inhibitor or concentration that can inhibit 50% of α–amylase activity was 1903µg/ml. Acarbose was used as a positive control in this study (IC50 = 0.24µg/ml). Conclusion: BRY-E has potency as an anti-diabetic, although the value is still small as compared to acarbose.