探討不同酵素對幾丁寡醣生產與特性的影響
學生姓名:
陳義洋
指導教授:
方翠筠
學 期:
113下
摘 要:
Chitosan is a non-cytotoxic polysaccharide that, upon hydrolysis, releases oligomers of different sizes that may have antioxidant, antimicrobial activity and the inhibition of cancer cell growth, among other applications. Thus, this study aims to use enzymatic hydrolysis to obtain chitooligosaccharides (COS) with different molecular weights. The fungus of the Aspergillus genus was identified by amplifying the ITS1-5.8S-ITS2 rDNA region and metaproteomic analysis. Chitosan hydrolysis assays compared the CEC with the commercial enzyme (Celluclast 1.5 L®). The ability to reduce the initial molecular mass of chitosan by 47.80, 75.24, and 93.26% after 2.0, 5.0, and 24 h of reaction, respectively, was observed. FTIR analyses revealed lower absorbance of chitosan oligomers’ spectral signals, and their crystallinity was reduced.In addition, two different non-specific proteolytic enzymes (papain and pepsin) and two carbohydrase enzymes (α-amylase and β-amylase) were used for the depolymerization of chitosan to produce COS. COS produced using pepsin enzyme had higher solubility compared to other three COS. Pepsin-COS had the highest DPPH radical scavenging and reducing power activity among the four COS. According to the patterns of molecular weight reduction, antioxidant activities, thermal behavior properties, four enzymes were found suitable for hydrolyzing chitosan into COS. These results conclude that crude enzyme concentrates show significant technical potential for obtaining chitosan oligomers of different sizes. Moreover, COS is superior to chitosan and therefore can be used as a biopreservative in the food industry to improve the quality, safety and shelf life of products.
陳義洋.pdf