Ellagic acid (EA), a naturally occurring bioactive phenolic compound largely found in pomegranate, exhibits significant health benefits due to its antioxidant, antimutagenic, and even anticancerogenic properties. The present work aimed to microencapsulate EA extracted from pomegranate peels. To improve the stability of EA, microencapsulation was applied with Spirulina as a coating material. For this purpose, ethanolic extracts obtained from pomegranate peels were used for microencapsulation. Response surface methodology combined with a three-level, three-variable Box-Behnken design (BBD) was applied to obtain optimum microencapsulation. The microparticles obtained under the optimized encapsulation conditions were further characterized by FT-IR and SEM. The results confirmed the encapsulation of EA in Spirulina cells. Then, the optimum microparticles were used in an in vitro release study. The results of the in vitro digestion with simulated gastrointestinal fluids could help to determine the content and biological activity of EA. In this study, the effect of encapsulation on the release properties of EA during simulated gastrointestinal digestion was also evaluated. HPLC-DAD analysis and the Folin-Ciocalteu and ABTS methods were helpful for characterization of EA in the simulated fluids. The release profile of EA indicated that in simulated intestinal fluid, the release was faster than that in gastric fluid. PRACTICAL APPLICATION: This study describes the microencapsulation of ethanolic extracts of pomegranate peel (PP) in Spirulina. This application has been performed to improve the stability and bioavailability of EA in the extracts. Optimum microencapsulation was obtained by response surface methodology with BBD. After the characterization of the obtained optimum Spirulina/EA mixture by FT-IR and SEM, an in vitro release study was conducted for stability research. The results will guide other researchers working on the determination of the content and biological activity of EA and on optimizing the microencapsulation process.

中文翻译：

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响应面法优化微藻中石榴皮鞣花酸的包封及其在模拟胃肠道下的控释研究

鞣花酸 (EA) 是一种天然存在的生物活性酚类化合物，主要存在于石榴中，由于其抗氧化、抗诱变甚至抗癌特性，显示出显着的健康益处。目前的工作旨在微囊化从石榴皮中提取的 EA。为了提高EA的稳定性，采用螺旋藻作为包衣材料进行微胶囊化。为此，从石榴皮中提取的乙醇提取物用于微胶囊化。应用响应面方法结合三级、三变量 Box-Behnken 设计 (BBD) 以获得最佳微胶囊化。在优化的包封条件下获得的微粒通过 FT-IR 和 SEM 进一步表征。结果证实了EA在螺旋藻细胞中的包封。然后，最佳微粒用于体外释放研究。模拟胃肠液体外消化结果有助于确定EA的含量和生物活性。在这项研究中，还评估了封装对模拟胃肠道消化过程中 EA 释放特性的影响。HPLC-DAD 分析以及 Folin-Ciocalteu 和 ABTS 方法有助于表征模拟流体中的 EA。EA的释放曲线表明，在模拟肠液中，其释放速度比在胃液中快。实际应用：本研究描述了石榴皮 (PP) 乙醇提取物在螺旋藻中的微胶囊化。已执行此应用以提高提取物中 EA 的稳定性和生物利用度。最佳微囊化是通过响应面法与 BBD 获得的。在通过 FT-IR 和 SEM 表征获得的最佳螺旋藻/EA 混合物后，进行了体外释放研究以进行稳定性研究。结果将指导其他研究人员确定 EA 的含量和生物活性以及优化微囊化过程。