Braham Fazia, Amaral Luísa M P F, Biernacki Krzysztof, Carvalho Daniel O, Guido Luis F, Magalhães Júlia M C S, Zaidi Farid, Souza Hiléia K S, Gonçalves Maria P
Département des Sciences Alimentaires, Faculté des Sciences de la Nature et de la Vie, Université de Bejaia, Route Targa Ouzemour, Bejaia 06000, Algeria.
REQUIMTE/LAQV, Departamento de Engenharia Química, Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
Foods. 2022 Aug 31;11(17):2641. doi: 10.3390/foods11172641.
In this work, a qualitative study of the phenolic content of leaves (MO), extracted with deep eutectic solvents (DES) based on choline chloride (ChCl) with lactic acid (LA) or glycerol (GLY), was performed by high-resolution mass spectrometry (HPLC-DAD-ESI-MS). The two solvents (DES-LA and DES-GLY) extract similar classes of phenolics, and ten compounds were identified. The antioxidant profile was also studied (TPC, TFC, DPPH, FRAP, ORAC, and ABTS). Both solvents show an efficient extraction of phenolic compounds and high antioxidant capacity was verified for the extracts. However, the DES-Gly have a higher capacity for polyphenolic extraction (TPC led to 38.409 ± 0.095 mg GAE.g and 2.259 ± 0.023 mg QE.g for TFC). Films based on methylcellulose (MC) containing different amounts of DES or MO extracts, acting as plasticizers, were developed and characterized regarding their mechanical, optical, water vapor permeability, and microstructural properties. All films are uniform, clear, and transparent with smooth, homogeneous surfaces. It was found that the presence of more than 10% of MO extract and/or DES provided more flexible films (Eb for MC 2%_DES 20% achieved 4.330 ± 0.27 %, and 8.15 ± 0.39 % for MC 2%_MO 20%) with less mechanical and barrier resistance. The ultimate objective of this study was to provide information that could assist in the development of antimicrobial active methylcellulose films for sliced wheat bread packaging.
在这项工作中，采用高分辨率质谱法（HPLC-DAD-ESI-MS）对基于氯化胆碱（ChCl）与乳酸（LA）或甘油（GLY）的低共熔溶剂（DES）提取的叶片（MO）酚类成分进行了定性研究。两种溶剂（DES-LA和DES-GLY）提取的酚类种类相似，共鉴定出10种化合物。还研究了抗氧化特性（总酚含量、总黄酮含量、DPPH、FRAP、ORAC和ABTS）。两种溶剂都能有效提取酚类化合物，提取物具有较高的抗氧化能力。然而，DES-甘油对多酚的提取能力更强（总酚含量为38.409±0.095毫克没食子酸当量/克，总黄酮含量为2.259±0.023毫克芦丁当量/克）。开发了基于甲基纤维素（MC）的薄膜，其中含有不同量的DES或MO提取物作为增塑剂，并对其机械、光学、水蒸气透过率和微观结构性能进行了表征。所有薄膜均均匀、清澈、透明，表面光滑、均匀。结果发现，当MO提取物和/或DES的含量超过10%时，薄膜更具柔韧性（MC 2%-DES 20%的断裂伸长率达到4.330±0.27%，MC 2%-MO 20%的断裂伸长率为8.15±0.39%），机械性能和阻隔性能降低。本研究的最终目的是提供有助于开发用于切片小麦面包包装的抗菌活性甲基纤维素薄膜的信息。
