College of Food Science and Technology, Zhejiang University of Technology, Hangzhou, People's Republic of China.
Key Laboratory of Food Macromolecular Resources Processing Technology Research (Zhejiang University of Technology), China National Light Industry, Beijing, China.
Crit Rev Food Sci Nutr. 2022;62(20):5638-5657. doi: 10.1080/10408398.2021.1888692. Epub 2021 Feb 22.
Phytosterols have been shown to lower cholesterol levels and to have antioxidant, anti-inflammatory and other biological activities. However, the high melting point and poor solubility limit their bioavailability and practical application. It is advantageous to modify phytosterols chemically and physically. This article reviews and discusses the chemical and physical modifications of phytosterols, as well as their effects on the bioavailability and possible toxicity in vivo. The current research on chemical modifications is mainly focused on esterification to increase the oil solubility and water solubility. For physical modifications (mainly microencapsulation), there are biopolymer-based, surfactant-based and lipid-based nanocarriers. Both chemical and physical modifications of phytosterols can effectively increase the absorption and bioavailability. The safety of modified phytosterols is also an important issue. Phytosterol esters are generally considered to be safe. However, phytosterol oxides, which may be produced during the synthesis of phytosterol esters, have shown toxicity in animal models. The toxicity of nanocarriers also needs further studies.
植物固醇已被证明可以降低胆固醇水平，具有抗氧化、抗炎等生物活性。然而，其高熔点和较差的溶解性限制了它们的生物利用度和实际应用。对植物固醇进行化学和物理修饰具有优势。本文综述和讨论了植物固醇的化学和物理修饰及其对体内生物利用度和潜在毒性的影响。目前对化学修饰的研究主要集中在酯化上，以提高油溶性和水溶性。对于物理修饰（主要是微胶囊化），有基于生物聚合物、基于表面活性剂和基于脂质的纳米载体。植物固醇的化学和物理修饰都可以有效地提高吸收和生物利用度。修饰后的植物固醇的安全性也是一个重要问题。植物固醇酯通常被认为是安全的。然而，在植物固醇酯合成过程中可能产生的植物固醇氧化物在动物模型中表现出了毒性。纳米载体的毒性也需要进一步研究。
