Green Extracts and UPLC-TQS-MS/MS Profiling of Flavonoids from Mexican Oregano (Lippia graveolens) Using Natural Deep Eutectic Solvents/Ultrasound-Assisted and Supercritical Fluids

Abstract

Mexican oregano (Lippia graveolens) is an important source of bioactive compounds, such as flavonoids. These have presented different therapeutic properties, including antioxidant and anti-inflammatory; however, their functionality is related to the quantity and type of compounds, and these characteristics depend on the extraction method used. This study aimed to compare different extraction procedures to identify and quantify flavonoids from oregano (Lippia graveolens). Emerging and conventional technologies include maceration with methanol and water, and ultrasound-assisted extraction (UAE) using deep eutectic solvents (DES) such as choline chloride-ethylene glycol, choline chloride-glycerol, and choline chloride-lactic acid. Supercritical fluid extraction using CO2 as a solvent was also studied. Six different extracts were obtained and the total reducing capacity, total flavonoid content, and antioxidant capacity by ABTS•+, DPPH•, FRAP, and ORAC were evaluated. In addition, flavonoids were identified and quantified by UPLC-TQS-MS/MS. Results showed that UAE-DES had the best extraction effect and antioxidant capacity using colorimetric methods. However, maceration-methanol was superior in compound content, and highlighting naringenin and phloridzin were the major compounds. In addition, this extract was microencapsulated by spray drying, which provided a protection feature of their antioxidant potential. Oregano extracts are rich in flavonoids and the microcapsules present promising results for future research.

Determination of Flavonoid Compounds in Shanxi Aged Vinegars Based on Hydrophobic Deep Eutectic Solvent VALLME-HPLC Method: Assessment of the Environmental Impact of the Developed Method

“…As far as we know, flavonoid extraction technologies include alcohol extraction, microwave extraction (MAE), supercritical fluid extraction (SFE), ultrasonic-assisted extraction (UAE), vortex-assisted extraction (VAE) and solid phase extraction (SPE). Among these, supercritical fluid extraction technology is considered a sustainable extraction method, as supercritical fluid can be combined with other conventional non-toxic/low toxic solvents [ 53 , 54 ]. However, the expensive equipment used in SFE hinders its wider application.…”

“…Our findings highlight the eco-friendly nature of the proposed method based on hydrophobic DESs, emphasizing their sensitivity and successful performance in extracting and determining target analytes in authentic vinegar samples. [53,54]. However, the expensive equipment used in SFE hinders its wider application.…”

Potential Agricultural Uses of Micro/Nano Encapsulated Chitosan: A Review

“…Microencapsulation using chitosan as an encapsulating agent is an emerging technology that protects active compounds from degradation, reduces incompatibility problems, and controls the release of active compounds, providing solutions to different issues in the agricultural field. The microencapsulation products are microparticles, microcapsules, and microspheres with different morphology and internal structure [24,25]. Spray drying and freeze-drying have been reported among the main microencapsulation technologies.…”