Department of Packaging and Materials Technology, Faculty of Agro-Industry, and Center for Advanced Studies in Nanotechnology and Its Applications in Chemical, Food and Agricultural Industries, Kasetsart University , 50 Phaholyothin Road, Chatuchak, Bangkok 10900, Thailand.
Department of Food Technology, Faculty of Science, Chulalongkorn University , 254 Phayathai Road, Pathumwan, Bangkok 10330, Thailand.
J Agric Food Chem. 2016 Sep 7;64(35):6694-707. doi: 10.1021/acs.jafc.6b02197. Epub 2016 Aug 29.
Caffeic acid phenethyl ester (CAPE) nanoparticles (NPs) with an average size of ∼40 nm obtained from TEM and binomial average sizes of ∼90 and ∼400 nm obtained from DLS were successfully produced by rapid expansion of subcritical solutions into liquid solvents (RESOLV). The minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of CAPE and CAPE-NPs were determined by plate count method against 12 pathogenic and spoilage bacteria and 3 strains of yeast. Total phenolic content (TPC) and antioxidant activities of CAPE-NPs were quantified and subsequently investigated using two assays, including 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and ferric reducing antioxidant power (FRAP). CAPE-NP-incorporated cellulose-based films were prepared and characterized. MICs and MBCs of CAPE-NPs against most bacteria and Candida albicans were 700 and 1400 μg/mL, respectively. CAPE-NPs yielded a TPC value of 426.74 μgGAE/mg and lower antioxidant activities than those of CAPE in ethanol (CAPE-EtOH), whereas BHT yielded lower FRAP than that of CAPE-NPs. The impregnation of CAPE into cellulose-based films was confirmed by FTIR spectra. Moreover, incorporation of only 0.5 wt % CAPE-NPs into the films resulted in an inhibitory effect against microorganisms. Fortunately, incorporation of higher concentration of CAPE-NPs-MC films led to a significantly higher antioxidant activity and vice versa. This indicated that CAPE-NPs significantly enhanced the antimicrobial and antioxidant activities of CAPE. The results show that the environmentally benign supercritical CO2 technique should be generally applicable to NP fabrication of other important bioactive ingredients, especially in liquid form. In addition, it is suggested that CAPE-NPs can be used to reduce the dosage of CAPE and improve their bioavailability and thus merit further investigation for bioactive packaging film and coating applications.
通过快速膨胀的亚临界溶液到液体溶剂（RESOLV）成功地制备了平均尺寸约为 40nm 的咖啡酸苯乙酯（CAPE）纳米粒子（NPs），其 TEM 平均尺寸为约 90nm 和 DLS 平均尺寸为约 400nm。采用平板计数法测定了 CAPE 和 CAPE-NPs 对 12 种致病性和腐败性细菌及 3 株酵母的最小抑菌浓度（MIC）和最小杀菌浓度（MBC）。通过两种测定方法，包括 2,2-二苯基-1-苦基肼（DPPH）自由基清除和铁还原抗氧化能力（FRAP），对 CAPE-NPs 的总酚含量（TPC）和抗氧化活性进行了定量，并随后进行了研究。制备并表征了载有 CAPE-NP 的纤维素基薄膜。CAPE-NPs 对大多数细菌和白色念珠菌的 MIC 和 MBC 分别为 700 和 1400μg/mL。与乙醇中的 CAPE（CAPE-EtOH）相比，CAPE-NPs 的 TPC 值为 426.74μgGAE/mg，抗氧化活性较低，而 BHT 的 FRAP 值低于 CAPE-NPs。FTIR 光谱证实了 CAPE 浸渍在纤维素基薄膜中。此外，将 0.5wt%CAPE-NPs 掺入薄膜中即可对微生物产生抑制作用。幸运的是，掺入更高浓度的 CAPE-NPs-MC 薄膜会显著提高抗氧化活性，反之亦然。这表明 CAPE-NPs 显著增强了 CAPE 的抗菌和抗氧化活性。结果表明，环境友好的超临界 CO2 技术应普遍适用于其他重要生物活性成分的 NP 制备，特别是在液体形式下。此外，建议使用 CAPE-NPs 来降低 CAPE 的剂量，提高其生物利用度，从而值得进一步研究用于生物活性包装膜和涂层应用。
