Nascimento Rosa E A, Monte Joana, Cadima Mafalda, Alves Vítor D, Neves Luísa A
LAQV/REQUIMTE, Chemistry Department, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, 2829-516 Caparica, Portugal.
LEAF, Linking Landscape, Environment, Agriculture and Food, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisbon, Portugal.
Polymers (Basel). 2021 Mar 9;13(5):843. doi: 10.3390/polym13050843.
This study seeks to render residues from banana plants into a useful byproduct with possible applications in wound dressings and food packaging. Films based on cellulose extracted from banana plant pseudostem and doped with phenolic compounds extracted from banana plant leaves were developed. The phenolic compounds were extracted using batch solid-liquid and Soxhlet methods, with different drying temperatures and periods of time. The total phenolic content and antioxidant activity were quantified. The optimum values were obtained using a three-day period batch-solid extraction at 40 °C (791.74 ± 43.75 mg/L). SEM analysis indicates that the pseudostem (PS) films have a porous structure, as opposed to hydroxyethyl cellulose (HEC) films which presented a homogeneous and dense surface. Mechanical properties confirmed the poor robustness of PS films. By contrast HEC films manifested improved tensile strength at low levels of water activity. FTIR spectroscopy reinforced the need to improve the cellulose extraction process, the success of lignin and hemicellulose removal, and the presence of phenolic compounds. XRD, TGA and contact angle analysis showed similar results for both films, with an amorphous structure, thermal stability and hydrophilic behavior.
本研究旨在将香蕉植株的残余物转化为一种有用的副产品，并探讨其在伤口敷料和食品包装方面的潜在应用。研究人员开发了基于从香蕉植株假茎中提取的纤维素并掺杂从香蕉植株叶片中提取的酚类化合物的薄膜。酚类化合物采用分批固液萃取法和索氏提取法进行提取，设置了不同的干燥温度和时间。对总酚含量和抗氧化活性进行了定量分析。在40℃下进行为期三天的分批固体萃取，获得了最佳值（791.74±43.75mg/L）。扫描电子显微镜（SEM）分析表明，与呈现均匀致密表面的羟乙基纤维素（HEC）薄膜不同，假茎（PS）薄膜具有多孔结构。力学性能证实了PS薄膜的坚固性较差。相比之下，HEC薄膜在低水分活度水平下表现出更高的拉伸强度。傅里叶变换红外光谱（FTIR）分析进一步表明，需要改进纤维素提取工艺，以成功去除木质素和半纤维素，并确认酚类化合物的存在。X射线衍射（XRD）、热重分析（TGA）和接触角分析显示，两种薄膜具有相似的结果，均呈现无定形结构、热稳定性和亲水行为。
