Extraction of Reducing Sugar with Anti-Oxidative Scavengers from Peels of Carya cathayensis Sarg.: Use of Subcritical Water

  • Shimanouchi, Toshinori (Graduate School of Environment and Life Science, Okayama University) ;
  • Ueno, Shohei (Graduate School of Environment and Life Science, Okayama University) ;
  • Yang, Wei (Graduate School of Environment and Life Science, Okayama University) ;
  • Kimura, Yukitaka (Graduate School of Environment and Life Science, Okayama University)
  • Received : 2013.07.23
  • Accepted : 2013.10.22
  • Published : 2014.03.30


The peels of Carya cathayensis Sarg. (PCCS) were treated under subcritical water conditions ($130^{\circ}C$ to $280^{\circ}C$ for 0 to 120 min). The extract from PCCS included reducing sugar, proteins, and compounds with radical scavenging activity. Addressing the reducing sugar that is a resource of bioethanol, we could maximize the reducing sugar under the subcritical water ($190^{\circ}C$ for 60 min) and obtain 0.24 g/g-sample together with 9.7 units/mg-sample of radical scavenging activity. The obtained extract was estimated to correspond to 1 L of bioethanol/100 g-sample. It was therefore considered that the treatment by subcritical water could yield reducing sugar and natural compounds with radical scavenging activity.



Supported by : Ministry of Education, Science, Sports, and Culture of Japan


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