본 연구에서는 Aspergillus oryzae CF1001 균주를 이용하여 잡곡당화음료 개발조건의 최적화와 향기성분을 분석하고 항당뇨 활성을 확인하고자 하였다. 중심합성실험계획법에 의해 당화온도 $50.71^{circ}C$, 호화시간 45.12분이 최적 당화조건으로 선정되었으며, 당화온도가 호화시간에 비하여 $Brix^{circ}$ 증가에 더 많은 영향을 미치는 것으로 확인되었다. 잡곡당화음료의 휘발성 향기성분은 33가지 동정성분과 29가지의 미지 성분이 분석되었다. 소장 내 당흡수와 관련된 ${alpha}$-glucosidase 활성억제능은 농도 의존적으로 증가하는 것으로 나타났다. HepG2 세포의 glucose uptake 활성을 확인한 결과, 인슐린에 관계없이 glucose uptake가 증가하였으며, 관련 단백질인 GLUT-2, -4의 발현 또한 증가하는 것으로 나타났다. 세포 내 당소모대사 관련 효소인 GK와 PDH도 증가하는 것으로 나타났으며, 잉여로 남은 glucose를 지방으로 전환 저장하는 ACL, ACC 유전자도 증가하는 것으로 나타났다. 이를 통해 잡곡당화음료가 glucose uptake와 세포 내 당소모대사 증가를 도우며, 남는 glucose를 지방으로 전환 저장시키는데 도움을 줄 것으로 사료된다.
Purpose: This study was conducted to establish the production conditions through optimization of the production process of beverages using Aspergillus oryzae CF1001, and to analyze volatile compounds and antidiabetic activity. Methods: The optimum condition was selected using the response surface methodology (RSM), through a regression analysis with the following independent variables gelatinization temperature (GT, $X_1$), saccharogenic time (ST, $X_2$), and dependent variable; ${Delta}E$ value (y). The condition with the lowest ${Delta}E$ value occurred with combined 45 min ST and $50^{circ}C$ GT. The volatile compounds were analyzed quantitatively by GC-MS. Results: Assessment of antidiabetic activity of saccharogenic mixed grain beverage (SMGB) was determined by measurement of ${alpha}$-glucosidase inhibition activity, and glucose uptake activity and glucose metabolic protein expression by reverse transcriptase polymerase chain reaction (RT-PCR) and western blot analysis. Results of volatile compounds analysis, 62 kinds of volatile compounds were detected in SMGB. Palmitic acid (9.534% ratio), benzaldehyde (8.948% ratio), benzyl ethyl ether (8.792% ratio), ethyl alcohol (8.35% ratio), and 2-amyl furan (4.826% ratio) were abundant in SMGB. We confirmed that ${alpha}$-glucosidase inhibition activity, glucose uptake activity, and glucose-metabolic proteins were upregulated by SMGB treatment with concentration dependent manner. Conclusion: Saccharogenic mixed grain beverage (SMGB) showed potential antidiabetic activity. Further studies will be needed in order to improve the taste and functionality of SMGB.
