The aims of the study were to investigate the effect of polyvinyl alcohol (PVA) and nano-SiO2within the thermoplastic starch (TPS) blends on the rate and extent of starch enzymatic hydrolysis using enzymes a-amylase and amyloglucosidase. The results of this study have revealed that blends with a nano-SiO2 content at 5 wt.% exhibited a significantly reduced rate and extent of starch hydrolysis. The results suggest that this may have been attributed to interactions between starch and nano-SiO2that further prevented enzymatic attack on the remaining starch phases within the blend. The total solids that remained after 6000 min were 54 wt.% (TPS:PVA); 61 wt.% (TPS:PVA:1% nano-SiO2); 64 wt.% (TPS:PVA:3% nano-SiO2); 68 wt.% (TPS:PVA:5% nano-SiO2). The rate of glucose production from each nanocomposite substrates was most rapid for the substrate without nano-SiO2and decreased with the addition of nano-SiO2, for TPS:PVA blend (226 mg/ml h), 166 mg/ml h (TPS:PVA:1% nano-SiO2), 122 mg/ ml h (TPS:PVA:3% nano-SiO2) and 94 mg/ml h for (TPS:PVA:5% nano-SiO2). Enzymatic degradation behaviour of TPS:PVA:nano-SiO2was based on the determinations of water resistance, weight loss and the reducing sugars. It has been established that the nanoparticles hinder degradation, while the susceptibility to enzymatic degradation varies in the order: TPS:PVA > TPS:PVA:nano-SiO2.
کلید واژگان :Enzymatic degradation Nanocomposites a-Amylase. Amyloglucosidase Nano-SiO2
ارزش ریالی : 1200000 ریال
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