Optimization of Supercritical CO(2) Extraction of Moringa oleifera Seed Oil Using Response Surface Methodological Approach and Its Antioxidant Activity

OBJECTIVES: Moringa (Moringa oleifera), also known as the Drumstick tree, is a Moringa plant found in the Moringa family. Moringa is rich in multiple biological aspects such as, protein, amino acids, fibers, vitamins, and essential minerals, including potassium, calcium, iron, and zinc. In addition, Moringa seeds contain a relatively large amount of oil, which has been shown to benefit human health. Moringa seed oil contains a high quantity of unsaturated fatty acids than most common edible oils. Supercritical CO(2) fluid extraction is particularly suitable for the separation of physiologically active substances and natural products, including plant seed oil. Thus, the present study aimed to determine the optimal process conditions of supercritical CO(2) fluid extraction of moringa seed oil. METHODS: We employed supercritical CO(2) fluid extraction as well as the response surface test design on the basis of single-factor experiment to investigate the three factors of extraction, temperature, time, and pressure, on the extraction rate of Moringa seed oil. RESULTS: The optimal process conditions were determined as extraction temperature of 45°C, extraction time of 2.5 h, extraction pressure of 50 MPa, and CO(2) flow rate of 240 L/h, resulting in a maximum yield of 38.54%. This resulting maximum yield is higher than prior extraction methods of moringa seed oil. Composition analysis shows that the extracted moringa seed oil is rich in unsaturated fatty acids, including oleic acid, octadecanoic acid, palmitic acid, stearic acid, eicosanoic acid, etc. Furthermore, we found that moringa seed oil exerted potent antioxidant activities on DPPH and hydroxyl radicals, and its efficacy was comparable to commercial peanut oil and tea oil. CONCLUSIONS: This study provides a scientific basis for the development and application of Moringa seed oil in functional food, nutraceutical, and cosmetic products. FUNDING SOURCES: This work was supported by General project of Basic and applied basic Research in Guangzhou (2,060,206); Natural Science Foundation of Guangdong basic and applied basic research foundation (2021A1515010965); Natural Science Foundation of Guangdong basic and applied basic research foundation ([2018]105), Laboratory opening project of Guangzhou Medical University (PX-1,020,423).