Department of Chemical, Biological, Pharmaceutical and Environmental Science, University of Messina, 98166 Messina, Italy.
Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, 98125 Messina, Italy.
Int J Mol Sci. 2024 Sep 14;25(18):9929. doi: 10.3390/ijms25189929.
Over the last ten years, researchers' efforts have aimed to replace the classic linear economy model with the circular economy model, favoring green chemical and industrial processes. From this point of view, biologically active molecules, coming from plants, flowers and biomass, are gaining considerable value. In this study, firstly we focus on the development of a green protocol to obtain the purification of anthocyanins from the flower of , based on simulation and on response surface optimization methodology. After that, we utilize them to manufacture and add new properties to bioplastics belonging to class 3, based on modified polyvinyl alcohol (PVA) with increasing amounts from 0.10 to 1.00%. The new polymers are analyzed to monitor morphological changes, optical properties, mechanical properties and antioxidant and antimicrobial activities. Fourier transform infrared spectroscopy (FTIR) spectra of the new materials show the characteristic bands of the PVA alone and a modification of the band at around 1138 cm and 1083 cm, showing an influence of the anthocyanins' addition on the sequence with crystalline and amorphous structures of the starting materials, as also shown by the results of the mechanical tests. These last showed an increase in thickening (from 29.92 μm to approx. 37 μm) and hydrophobicity with the concomitant increase in the added anthocyanins (change in wettability with water from 14° to 31°), decreasing the poor water/moisture resistance of PVA that decreases its strength and limits its application in food packaging, which makes the new materials ideal candidates for biodegradable packaging to extend the shelf-life of food. The functionalization also determines an increase in the opacity, from 2.46 to 3.42 T%/mm, the acquisition of antioxidant activity against 2,2-diphenyl-1-picrylhdrazyl and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) radicals and, in the ferric reducing power assay, the antimicrobial (bactericidal) activity against different strains at the maximum tested concentration (1.00% of anthocyanins). On the whole, functionalization with anthocyanins results in the acquisition of new properties, making it suitable for food packaging purposes, as highlighted by a food fresh-keeping test.
在过去的十年中，研究人员一直致力于将经典的线性经济模式转变为循环经济模式，支持绿色化学和工业过程。从这个角度来看，来自植物、花卉和生物质的生物活性分子的价值正在不断提高。在这项研究中，我们首先专注于开发一种绿色协议，从 花中提取纯化的花色苷，基于模拟和响应面优化方法。之后，我们将它们用于制造和添加新的特性到属于第 3 类的生物塑料中，基于改性聚乙烯醇（PVA），添加量从 0.10 到 1.00%不等。对新聚合物进行分析，以监测形态变化、光学性能、机械性能以及抗氧化和抗菌活性。新材料的傅里叶变换红外光谱（FTIR）谱显示了 PVA 本身的特征带，以及在约 1138cm 和 1083cm 处的带的修饰，表明花色苷的添加对起始材料的结晶和无定形结构的序列有影响，这也可以从机械测试的结果中看出。这些结果表明，随着添加的花色苷的增加（润湿性从 14°变为 31°），厚度（从 29.92μm 增加到约 37μm）和疏水性增加，同时降低了 PVA 的耐水/湿性差，这降低了其强度并限制了其在食品包装中的应用，这使得新材料成为可生物降解包装的理想选择，可以延长食品的保质期。功能化还导致不透明度从 2.46 增加到 3.42T%/mm，获得了对 2,2-二苯基-1-苦基肼基和 2,2'-氮杂双（3-乙基苯并噻唑啉-6-磺酸）自由基的抗氧化活性，并且在铁还原能力测定中，对不同 菌株的抗菌（杀菌）活性在测试的最大浓度（1.00%的花色苷）下。总的来说，花色苷的功能化导致获得了新的特性，使其适合食品包装用途，正如食品保鲜测试所强调的那样。
