Background: This study was carried out to determine the physicochemical components of Rehmannia glutinosa (RG) fermented with Rhizopus delemar.
Methods and Results: Physicochemical components such as changes in moisture content, pH value, total acidity, amount of reducing sugars as well as quantity of free sugars, free amino acids, and catalpol were investigated. Result showed that, the moisture content ranged from 64.26 to 65.51%. The pH and total acidity of the fermented RG decreased significantly during fermentation. The reducing sugar content ranged from 0.10 to 1.34%. The most abundant main free sugars were identified as raffinose, xylose, glucose, fructose, and sucrose. The sucrose content in 80% ethanol and in water extracts increased during RG fermentation. In total, 26 free amino acids were detected, including seven essential amino acids. In addition, the quantity of free amino acids decreased significantly during fermentation. Finally, the catalpol content of the fermented RG was highest on the 2nd day of fermentation at 2,028.67㎎/ 100 g.
Conclusions: These results indicated that fermentation of Rhizopus delemar could be used to enhance biological activity, and that fermented RG could be used as a functional material and as an edible resource in food and functional materials industries.

ABSTRACT
 서 언
 재료 및 방법
  1. 실험재료
  2. 균주 배지 및 배양조건
  3. 균주 배양 및 발효 지황 제조
  4. 발효 지황의 수분 함량, pH 및 산도 측정
  5. 환원당 측정
  6. 발효 지황 추출물 제조
  7. 유리당 분석
  8. 유리 아미노산 분석
  9. catalpol 함량분석
  10. 통계처리
 결과 및 고찰
  1. 발효기간 중 지황의 이화학적 특성
  2. 발효 지황의 유리당 함량 분석
  3. 발효 지황의 유리 아미노산 분석
  4. 발효 지황의 Catalpol 함량 분석
 REFERENCES

• 송빛나(농촌진흥청 국립농업과학원 농식품자원부 발효가공식품과) | Bitna Song (Fermentated and Processed Food Science Division, NIAS, RDA)
• 이다빈(농촌진흥청 국립농업과학원 농식품자원부 발효가공식품과) | Dabin Lee (Fermentated and Processed Food Science Division, NIAS, RDA)
• 박보람(농촌진흥청 국립농업과학원 농식품자원부 발효가공식품과) | Boram Park (Fermentated and Processed Food Science Division, NIAS, RDA)
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• 김소영(농촌진흥청 국립농업과학원 농식품자원부 발효가공식품과) | So Young Kim (Fermentated and Processed Food Science Division, NIAS, RDA)
• 박신영(농촌진흥청 국립농업과학원 농식품자원부 발효가공식품과) | Shin Young Park (Fermentated and Processed Food Science Division, NIAS, RDA) Corresponding author