LAUSR

Abstract In this research, the bioactive compounds of Securigera securidaca seed extract were microencapsulated in the sucrose matrix during the co-crystallization process. Important components of plant seed extract include flavonoids, alkaloids, tannins, sterols and palmitic acid. The structural properties of the microencapsulated powder and thermal properties were examined by electron microscopy and differential scanning calorimetry, respectively. The physicochemical properties (solubility, moisture, hygroscopicity, and aqueous activity) and antioxidant activity (measurements of phenolic compounds, total flavonoid content, hydroxyl radical scavenging activity, DDPH, ABTS, and reducing power) were also determined for the product. Structural analysis indicated a porous structure and an efficient microencapsulation process. Thermal properties of all samples showed a major peak at the temperature range of 190 °C similar to the melting point of sucrose. The microencapsulation efficiency increased with increasing the extract concentration in the co-crystallized powder. The powder with a concentration of 16% of the extract had the utmost effect on radical scavenging of DDPH, ABTS, hydroxyl, and reducing power (78.51, 80.02, 58.51%, and 0.91, respectively). Levels of aqueous activity, moisture content, and hygroscopicity of powders revealed that the produced product was stable with suitable properties for storage. After 4 months of storage in different environmental conditions (ambient temperature, darkness, refrigeration, and artificial light), the maximum retention (about 94.9%) of phenolic compounds and antioxidant properties (about 82.24%) were observed for a powder containing 16% of the extract stored in dark conditions. Microencapsulation by co-crystallization can be used as an efficient method to preserve bioactive compounds against environmental conditions and in food formulations.