Abstract:

The influences of different drying methods, including traditional hot air drying, freeze drying and vacuum drying,
on the physio-chemical properties and antioxidant activities of crude polysaccharides extracted from Tremella fuciformis
(TFPs) were investigated. The results showed that freeze-dried TFPs (TFPs-F) had higher extraction efficiency, total sugar
content and viscosity. It was also found that molecular size distribution and antioxidant activities of TFPs were affected by
three different drying methods. The IC50 for reducing power and scavenging activities against 1,1-diphenyl-2-picrylhydrazyl
(DPPH free radical), hydroxyl and superoxide anion radicals of TFPs-F were 2.61, 1.64, 1.78, and 1.75 mg/mL, respectively.
Moreover, it was clearly demonstrated that the IC50 of traditional hot air dried and vacuum dried TFPs was higher than that
of low temperature freeze dried TFPs. The data obtained in vitro models suggest that freeze drying is an appropriate and
effective way of obtaining the polysaccharides with antioxidant activity from Tremella fuciformis.

Key words: Tremella fuciformis polysaccharides, drying methods, physio-chemical properties, antioxidant activity