National Laboratory of Nanotechnology for Agribusiness (LNNA), Embrapa Instrumentation (CNPDIA), São Carlos (SP), Brazil.
J Agric Food Chem. 2013 Jul 24;61(29):7110-9. doi: 10.1021/jf402110g. Epub 2013 Jul 12.
This paper reports on the development of bioactive edible films based on pectin as a dietary matrix and magnesium hydroxide (Mg(OH)2) nanoplates as a reinforcing filler. Nanocomposites of high-methoxyl (HM) and low-methoxyl (LM) pectins were prepared using the casting method at concentrations of Mg(OH)2 ranging from 0.5 to 5 wt %. Atomic force microscopy and FTIR spectroscopy were employed to characterize the nanocomposite structure. The tensile properties and thermal stability of the nanocomposites were also examined to ascertain the effect of Mg(OH)2 inclusion and degree of methoxylation. The results provided evidence that the Mg(OH)2 nanoplates were uniformly dispersed and interacted strongly with the film matrix. The mechanical and thermal properties were significantly improved in the nanocomposite films compared to the control. Mg(OH)2 nanoplates were more effective in improving properties of LM pectin. Preliminary migration studies using arugula leaves confirmed that pectin-Mg(OH)2 nanocomposites can release magnesium hydroxide by contact, demonstrating their potential for magnesium supplementation in bioactive packaging.
本文报告了基于果胶作为膳食基质和氢氧化镁（Mg(OH)2）纳米片作为增强填料的生物活性可食用膜的开发。使用浇铸法在浓度为 0.5 至 5wt%的范围内制备了高甲氧基（HM）和低甲氧基（LM）果胶的纳米复合材料。原子力显微镜和傅里叶变换红外光谱用于表征纳米复合材料的结构。还检查了纳米复合材料的拉伸性能和热稳定性，以确定 Mg(OH)2的包含和甲氧基化程度的影响。结果表明，Mg(OH)2纳米片均匀分散并与膜基质强烈相互作用。与对照相比，纳米复合膜的机械和热性能显著提高。与 LM 果胶相比，Mg(OH)2纳米片在提高性能方面更有效。使用菠菜叶进行的初步迁移研究证实，果胶-Mg(OH)2纳米复合材料可以通过接触释放氢氧化镁，表明它们在生物活性包装中作为镁补充剂的潜力。
