Production and Characterization of a New α-Glucosidase Inhibitory Peptide fromAspergillus oryzaeN159-1

Abstract

An α-glucosidase inhibitor was developed from Aspergillus oryzae N159-1, which was screened from traditional fermented Korean foods. The intracellular concentration of the inhibitor reached its highest level when the fungus was cultured in tryptic soy broth medium at 27℃ for five days. The inhibitor was purified using a series of purification steps involving ultrafiltration, Sephadex G-25 gel permeation chromatography, strong cation exchange solid phase extraction, reverse-phase high performance liquid chromatography, and size exclusion chromatography. The final yield of the purification was 1.9%. Results of the liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis indicated that the purified α-glucosidase inhibitor was a tri-peptide, Pro-Phe-Pro, with the molecular weight of 360.1 Da. The IC50 value of the peptide against α-glucosidase activity was 3.1 mg/mL. Using Lineweaver-Burk plot analysis, the inhibition pattern indicated that the inhibitor acts as a mixed type inhibitor.

Preparation of bioactive peptides with antidiabetic, antihypertensive, and antioxidant activities and identification of α‐glucosidase inhibitory peptides from soy protein

“…Compared with the previously reported hypoglycemic peptides, such as N159-1 (PFP separated from Aspergillus oryzae) (Kang, Yi, & Lee, 2013), albumin (KLPGF) (Yu, Yin, Zhao, Liu, & Chen, 2012), and egg white protein (RVPSLM) (Yu et al, 2011), there appear to be no primary structural homology to the four oligopeptides we found. It is not difficult to point out that hydrophobic amino acids were common in these hypoglycemic peptides.…”

Antidiabetic potential of a peptide isolated from an endophyticAspergillus awamori

“…A peptide of 360 Da isolated from Aspergillus oryzae possessed alpha glucosidase inhibitory activity (Kang et al . ). Purified and semi purified proteinaceous α‐amylase inhibitors from wheat kernels have also been reported in the literature (Prestidge and Gallagher ; Borzoei et al .…”

“…Kang et al . () isolated a 360 Da peptide from As. oryzae with mixed type of inhibition against alpha glucosidase.…”

“…The mode of inhibition of the purified peptide was found to be mixed type against both enzymes. Kang et al (2013) isolated a 360 Da peptide from As. oryzae with mixed type of inhibition against alpha glucosidase.…”

Isolation of -glucosidase inhibitors from soil borne Aspergillus terreus and Cladosporium herbarum

“…Aspergillus aculeatus is proved to have good α-glucosidase inhibitory activity (Ingavat et al, 2009). Aspergillus oryzae has also been screened for development of α-glucosidase inhibitory peptide (Kang et al, 2013).…”