Tiozon Rhowell Navarro, Ong Glenn Vincent P, Sartagoda Kristel June D, Duque Sheba Mae M, Alseekh Saleh, Bonto Aldrin P, Gempesaw Shem, Pratap Vipin, Reginio Florencio C, Tengco Jonina Marie J, Seagan Christian, Tolentino Joel H G, Santiago Dennis Marvin O, Fernie Alisdair R, Sreenivasulu Nese
Consumer-driven Grain Quality and Nutrition Center, Rice Breeding Innovations Platform, International Rice Research Institute, Los Baños 4030, Philippines.
Max-Planck-Institute of Molecular Plant Physiology, Am Mühlenberg 1, Potsdam-Golm, 14476, Germany.
Food Hydrocoll Health. 2025 Jun;7:None. doi: 10.1016/j.fhfh.2025.100221.
Pigmented paddy rice is rich in a diverse array of phytochemicals that confer notable antioxidant and anticancer properties. However, the stability and bioaccessibility of these bioactive compounds present significant challenges. In this study, 542 brown (including pigmented and non-pigmented) whole grain rice samples were screened for their antioxidant components and capacity, leading to the identification of three superior cultivars: Balatinao variable purple rice, Ketan Hitam variable purple rice, and Kintuman red rice. Using response surface methodology, rice bran extracts from these cultivars were subjected to microencapsulation to stabilize the phytochemicals. Among the microencapsulated rice bran extracts (MRBEs), Ketan Hitam MRBE demonstrated significantly higher total phenolic content (TPC) and antioxidant capacity. This enhancement is likely due to the increased concentrations of isovitexin, luteolin 7-glucoside, and vitexin following microencapsulation. Furthermore, compared to non-encapsulated rice bran extracts, MRBEs exhibited significantly improved anticancer activity against HCT116 (colon) and A549 (lung) cancer cell lines ( < 0.05). Subsequent fractionation of the MRBE allowed for the identification of the most bioactive fractions, which contained metabolites effective against these cancer cell lines. In addition, bioaccessibility assays revealed a controlled release of 19 targeted phenolic compounds. This release profile was characterized by an initial increase during the gastric digestion phase, followed by a decrease in the intestinal phase. Notably, phenolic compounds such as chlorogenic acid, gallic acid, and vanillin were preserved across the three rice varieties after microencapsulation. These findings underscore the potential of MRBEs as functional food ingredients or supplements, offering improved bioaccessibility of phenolics, enhanced antioxidant properties, and promising anticancer activity. The results support the integration of rice bran extracts into the rice value chain, promoting their use in functional health applications.
有色水稻富含多种植物化学物质，具有显著的抗氧化和抗癌特性。然而，这些生物活性化合物的稳定性和生物可及性存在重大挑战。在本研究中，对542个棕色（包括有色和无色）全谷物水稻样本进行了抗氧化成分和能力筛选，鉴定出三个优良品种：巴拉蒂瑙可变紫稻、凯坦黑米可变紫稻和金图曼红米。采用响应面法对这些品种的米糠提取物进行微胶囊化处理，以稳定植物化学物质。在微胶囊化米糠提取物（MRBEs）中，凯坦黑米MRBE的总酚含量（TPC）和抗氧化能力显著更高。这种增强可能是由于微胶囊化后异荭草素、木犀草素7-葡萄糖苷和荭草素浓度增加所致。此外，与未微胶囊化的米糠提取物相比，MRBEs对HCT116（结肠）和A549（肺）癌细胞系的抗癌活性显著提高（<0.05）。随后对MRBE进行分级分离，鉴定出最具生物活性的级分，其中含有对这些癌细胞系有效的代谢物。此外，生物可及性分析显示19种目标酚类化合物的控释。这种释放模式的特点是在胃消化阶段初期增加，随后在肠道阶段减少。值得注意的是，微胶囊化后，绿原酸、没食子酸和香草醛等酚类化合物在三个水稻品种中均得以保留。这些发现强调了MRBEs作为功能性食品成分或补充剂的潜力，其酚类物质的生物可及性提高，抗氧化性能增强，抗癌活性前景广阔。结果支持将米糠提取物纳入水稻价值链，促进其在功能性健康应用中的使用。
