Antioxidant activity and porphyran content in hydrothermal extracts of Porphyra Yezoensis (Susabinori)

摘要

Porphyran was extracted from dried Porphyra yezoensis (Susabinori) with subcritical water. Susabinori is a popular sea food in Asian countries such as Japan and Korea, which is produced from seaweed. Susabinori contains a large amount of acidic polysaccharide called porphyran with antioxidation activity. Porphyran has physiological activity such as immune activity. In this work, hydrothermal extraction of porphyran was carried out under the conditions at temperatures of 80, 120, and 160°C for 200 minutes in a batch reactor of 8.8mL volume. The optimum condition of the extraction was the temperature at 160°C and the reaction time of 60 minutes where the yield attained to 25.6 wt% of the sample material. Molecular weight of porphyran tended to smaller with an increase in temperature and reaction time. Moreover, the antioxidant activity of extracts was affected by the extraction temperature and reaction time.