Istanbul Technical University, Faculty of Science and Letters, Department of Chemistry, Maslak TR34469, Istanbul, Turkey.
Istanbul Technical University, Faculty of Science and Letters, Department of Chemistry, Maslak TR34469, Istanbul, Turkey.
Carbohydr Polym. 2015;127:19-27. doi: 10.1016/j.carbpol.2015.03.024. Epub 2015 Mar 21.
In this study modification of xylan via Mannich reaction in aqueous basic solution to obtain dimethylaminomethylated products and characterization of modified xylan were examined. Components were xylan (obtained from corn cob and used without modification) as active hydrogen containing compound, formaldehyde as carbonyl compound having no α-hydrogen and dimethylamine. Mannich reaction was used with different parameters such as component concentration, reaction temperature, and time. The highest modification was observed about 35°C with a nitrogen content of 4.6% by weight indicating successive modification. Both 1D and 2D NMR measurements displayed new signals related with aminomethyl groups. Spectral characterizations indicated that aminomethylation took place on oxygen sites. Moreover modified xylan could form film while xylan could not without an auxiliary agent. Antimicrobial activity tests indicated that modified xylan acted as a bacteriostatic material.
本研究通过曼尼希反应在碱性水溶液中对木聚糖进行修饰，以获得二甲氨基甲基化产物，并对修饰后的木聚糖进行了表征。反应物为木聚糖（从玉米芯中提取，未经修饰），作为含活泼氢的化合物；甲醛作为无α-氢的羰基化合物；二甲胺。采用不同的参数，如反应物浓度、反应温度和时间，进行曼尼希反应。在 35°C 下，氮含量达到 4.6%（重量），表明连续修饰。1D 和 2D NMR 测量均显示出与氨甲基基团有关的新信号。光谱特征表明，氨甲基化发生在氧原子上。此外，改性木聚糖可以形成薄膜，而木聚糖则不能，需要添加助剂。抗菌活性测试表明，改性木聚糖具有抑菌作用。
