Study on ultrasonic-assisted deep eutectic solvent extraction process and in vitro antioxidant of Anchusa italica Retz. Flowers

Anchusa italica Retz. Flowers (Airfs) is a perennial herb belonging to the Boraginaceae family. A variety of pharmacological agents are employed in the treatment of a multitude of cardiovascular disorders. The study employs ultra-performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry (UPLC-Q-Exactive Orbitrap-MS) to elucidate the complex chemical composition of these flowers, identifying a multitude of bioactive constituents. It is noteworthy that rosmarinic acid (RA) emerged as a predominant compound, a finding underscored by its high relative content of 39.8511% in the methanolic extract of the flowers.

The innovative approach involved the use of a deep eutectic solvent (DES), a green extraction medium, which, when combined with ultrasonic assistance, resulted in a notable enhancement of the extraction yield of total polyphenols and RA. The optimization of this extraction process was achieved through a meticulous response surface methodology, which identified critical factors and their optimal conditions. These included a water content of 29.051 % and a material-liquid ratio of 20.961 mL/g. The optimal conditions were determined to be an extraction time of 35.725 min, an ultrasonic power of 240.342 W.

In vitro antioxidant assays further substantiated the therapeutic potential of Anchusa italica Retz. flowers. RA demonstrated remarkable DPPH and ABTS radical scavenging capabilities, with rates exceeding 90%. The comprehensive evaluation value (CEV), derived from the total polyphenol content (TPC) and RA, was optimized under the aforementioned conditions, yielding a CEV of 222.452.

The optimized extraction method presents a sustainable and efficient protocol for the isolation of bioactive compounds from natural sources, thereby underscoring the significance of this research in the field of natural product chemistry and ultrasonics Sonochemistry.