Department of Chemistry, Faculty of Applied Sciences, Universiti Teknologi MARA, Perlis Branch, 02600 Arau, Perlis, Malaysia.
Department of Polymer Technology, Faculty of Applied Sciences, Universiti Teknologi MARA, Perlis Branch, 02600 Arau, Perlis, Malaysia.
Int J Biol Macromol. 2018 Oct 15;118(Pt A):1183-1192. doi: 10.1016/j.ijbiomac.2018.06.103. Epub 2018 Jun 23.
Momordica charantia bioactive polysaccharide (MCBP) was used as an alternative source for the production of bio-based plastics (BPs) with choline chloride/glycerol-based deep eutectic solvent (DES) as a plasticizer. In this study, MCBP was initially extracted using 0.1 M citric acid at temperature 80 °C for 2 h, precipitated using ethanol, and then lyophilized. Subsequently, seven BPs were prepared: MCBP without plasticizer (MCBP), with 1% (w/w) of glycerol (MCBP-G), or with 1% (w/w) of DES at different choline chloride/glycerol molar ratios (i.e. 1.5:1, 1:1, 1:1.5, 1:2, and 1:3). The properties of these BPs were then investigated. Results showed that the tensile strains, stresses and moduli were in the range of 1.3-13.3%, 4.8-19.1 MPa and 132-2487 MPa, respectively. The melting temperatures were found in the range of 92.6-111.4 °C whereas the moisture absorptions and water vapour transmission rates (WVTR) of BPs were 1.4-6.5% and 3.6-5.4 mg/m·s, respectively. The results also showed that these BPs exhibited bioactivities, such as microbial inhibitory activity (19.5-32.3 mm), free radical scavenging activity (10.3-18.3%) and ferric reducing antioxidant power (FRAP, 16.1-20.0 mM). In addition, it was observed that using DES as a plasticizer had improved the properties of BP, such as tensile strain (354.7-937.5%), melting temperature (4.6-20.3%), radical scavenging activity (0.6-88.6%), FRAP (0.9-18.7%) and antimicrobial activity (12.3-33.6%) compared to MCBP, due to the fact DES has caused different degrees of plasticization via hydrogen bonds and ionic bonds with the polymer chains, and induced a lower pH condition. Therefore, it was suggested that these BPs with DES could contribute to food preservation properties.
苦瓜生物活性多糖 (MCBP) 被用作替代来源，以氯化胆碱/甘油基深共晶溶剂 (DES) 为增塑剂生产生物基塑料 (BPs)。在这项研究中，首先使用 0.1 M 柠檬酸在 80°C 温度下提取 2 小时提取 MCBP，用乙醇沉淀，然后冻干。随后，制备了七种 BPs：不含增塑剂的 MCBP（MCBP）、添加 1%（w/w）甘油的 MCBP（MCBP-G）或不同氯化胆碱/甘油摩尔比（即 1.5:1、1:1、1:1.5、1:2 和 1:3）的 1%（w/w）DES 的 MCBP。然后研究了这些 BPs 的性能。结果表明，拉伸应变、应力和模量分别在 1.3-13.3%、4.8-19.1 MPa 和 132-2487 MPa 的范围内。发现熔融温度在 92.6-111.4°C 范围内，而 BPs 的吸湿性和水蒸气透过率 (WVTR) 分别为 1.4-6.5%和 3.6-5.4 mg/m·s。结果还表明，这些 BPs 表现出生物活性，如微生物抑制活性 (19.5-32.3mm)、自由基清除活性 (10.3-18.3%) 和铁还原抗氧化能力 (FRAP，16.1-20.0mM)。此外，观察到使用 DES 作为增塑剂可以改善 BP 的性能，例如拉伸应变 (354.7-937.5%)、熔融温度 (4.6-20.3%)、自由基清除活性 (0.6-88.6%)、FRAP (0.9-18.7%) 和抗菌活性 (12.3-33.6%)，与 MCBP 相比，这是由于 DES 通过氢键和离子键与聚合物链发生不同程度的增塑作用，并诱导较低的 pH 值条件。因此，建议使用 DES 的这些 BP 可以有助于食品保鲜性能。
