Abstract：
Walnut isolate protein (WPI)-epigallocatechin gallate (EGCG) conjugates can be employed to creat food-grade delivery systems for preserving bioactive compounds. In this study, WPI-EGCG nanoparticles (WENPs) were developed for encapsulating lycopene (LYC) using the ultrasound-assisted method. The results indicated successful loading of LYC into these WENPs, forming the WENPs/LYC (cylinder with 200-300 nm in length and 14.81-30.05 nm in diameter). Encapsulating LYC in WENPs led to a notable decrease in release rate and improved stability in terms of thermal, ultraviolet (UV), and storage conditions compared to free LYC. Simultaneously, WENPs/LYC exhibited a synergistic and significantly higher antioxidant activity with an EC50 value of 23.98 μg/mL in HepG2 cells compared to free LYC\'s 31.54 μg/mL. Treatment with WENPs/LYC led to a dose-dependent restoration of intracellular antioxidant enzyme activities (SOD, CAT, and GSH-Px) and inhibition of intracellular malondialdehyde (MDA) formation. Furthermore, transcriptome analysis indicated that enrichment in glutathione metabolism and peroxisome processes following WENPs/LYC addition. Quantitative real-time reverse transcription PCR (qRT-PCR) verified the expression levels of related genes involved in the antioxidant resistance pathway of WENPs/LYC on AAPH-induced oxidative stress. This study offers novel perspectives into the antioxidant resistance pathway of WENPs/LYC, holding significant potential in food industry.
摘要：
核桃分离蛋白（WPI）-表没食子儿茶素没食子酸酯（EGCG）缀合物可用于创建食品级递送系统，以保存生物活性化合物。在这项研究中,使用超声辅助方法开发了WPI-EGCG纳米颗粒（WENPs）用于包封番茄红素（LYC）。结果表明LYC成功装载到这些WENPs中，形成WENPs/LYC(长度为200-300nm,直径为14.81-30.05nm的圆柱体)。将LYC封装在WENPs中导致释放速率显着降低，并改善了热稳定性，紫外线(UV),和与游离LYC相比的储存条件。同时,与游离LYC的31.54μg/mL相比，WENPs/LYC在HepG2细胞中表现出协同且显着更高的抗氧化活性，EC50值为23.98μg/mL。用WENPs/LYC处理导致细胞内抗氧化酶活性的剂量依赖性恢复（SOD，CAT,和GSH-Px）和抑制细胞内丙二醛（MDA）形成。此外，转录组分析表明，添加WENPs/LYC后，谷胱甘肽代谢和过氧化物酶体过程的富集。实时定量逆转录PCR(qRT-PCR)验证了WENPs/LYC在AAPH诱导的氧化应激中抗氧化抗性通路相关基因的表达水平。本研究为WENPs/LYC的抗氧化途径提供了新的视角，在食品工业中拥有巨大的潜力。
