Abstract

Ardisia compressa K. (ACK) fruits are a potential source of antioxidant compounds like phenolics and anthocyanins. ACK extracts made with aqueous ethanol (E75) yielded the highest total phenolic content (TPC) and antioxidant activity (AA) by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) assays. Water-in-oil nanoemulsions (NE_W/O) were produced by spontaneous emulsification, in order to provide longer stability to functional activities from ACK extract, and formulated using ACK extract (10–30%wt.), rosemary essential oil (REO), and Tween 80:Span 80 (10–30% wt.). Resultant NE_W/O were placed in a pseudo-ternary phase diagram and classified based on their visual performance, like phase separation, opacity, or translucent-stable systems. The latter displayed smaller hydrodynamic droplet sizes and better stability and were selected for physicochemical characterization. Physical stability through the hydrodynamic diameter, turbidity, and color attributes was monitored until 93 d at 25 °C under light exposure (LE) and dark. A first-order model was used for the first two variables, with rate kinetic constants (k) from 10⁻⁶ to 10⁻⁸ s⁻¹. Color index (CI) showed higher reduction when NE_W/O were stored under LE, whereas total color difference (TCD) values were higher than 5.5, indicating marked differences in visual color compared to fresh NE_W/O (t =0 d). Chemical stability from NE_W/O made with 30% w/w of ACK extract (NE30) displayed the best stability against pH changes, and TPC and AA during storage time, exhibiting also good antimicrobial susceptibility (AMS) against Gram-positive and Gram-negative bacteria with a synergistic effect of enhanced AMS than that observed in their respective individual components, even after storage time.

摘要

Ardisia compressa K. (ACK) 水果是酚类和花青素等抗氧化化合物的潜在来源。用含水乙醇 (E75) 制成的 ACK 提取物通过 1,1-二苯基-2-苦基肼 (DPPH) 和 2,2'-azino-bis-3-ethylbenzothiazolin 产生最高的总酚含量 (TPC) 和抗氧化活性 (AA) -6-磺酸 (ABTS) 测定。油包水纳米乳液 (NE _W/O ) 通过自发乳化制备，以使 ACK 提取物的功能活性具有更长的稳定性，并使用 ACK 提取物（10-30%wt.）、迷迭香精油（REO）配制而成) 和 Tween 80:Span 80 (10–30% wt.)。结果 NE _W/O被放置在伪三元相图中，并根据它们的视觉性能进行分类，如相分离、不透明度或半透明稳定系统。后者表现出更小的流体动力学液滴尺寸和更好的稳定性，并被选择用于物理化学表征。在 25 °C 光照 (LE) 和黑暗条件下，通过流体动力学直径、浊度和颜色属性监测物理稳定性直到 93 天。前两个变量使用一阶模型，速率动力学常数 ( k ) 从 10 ^-6到 10 ^-8 s ^-1。_{当 NE W/O}时，颜色指数 (CI) 显示出更高的降低储存在 LE 下，而总色差 (TCD) 值高于 5.5，表明与新鲜 NE _W/O ( t = 0 d) 相比，视觉颜色存在显着差异。用 30% w/w 的 ACK 提取物 (NE30) 制成的 NE _W/O的化学稳定性在储存期间对 pH 变化、TPC 和 AA 表现出最佳稳定性，对革兰氏阳性菌和革兰氏阳性菌也表现出良好的抗菌敏感性 (AMS) -负细菌具有增强的 AMS 的协同作用，而不是在它们各自的单独成分中观察到的，即使在储存时间之后也是如此。