Tailoring Natural Solvents: Deep Eutectic Approach for Recovering Bioactives From Prunus spinosa L

Area of Science:

• Green Chemistry
• Natural Product Extraction
• Analytical Chemistry

Background:

• Deep eutectic solvents (DES) offer a sustainable alternative to traditional solvents for natural product extraction.
• Prunus spinosa L. (blackthorn) is a rich source of bioactive compounds with potential health benefits.
• Efficient extraction methods are crucial for maximizing the yield of valuable compounds from plant materials.

Purpose of the Study:

• To evaluate various choline chloride (ChCl)-based deep eutectic solvents (DES) for the extraction of bioactive compounds from Prunus spinosa L. fresh fruit.
• To compare the extraction efficiency of optimized DES with conventional solvents like aqueous ethanol and water.
• To determine the optimal conditions for the extraction of total phenolic content (TPC), total anthocyanin content (TAC), and antioxidant activity (AA) using response surface methodology.

Main Methods:

• Preparation of ChCl-based DES using different hydrogen bond donors (urea, ethylene glycol, glycerol) and acids (lactic, formic, propionic, acetic) at various molar ratios.
• Homogeniser-assisted extraction of Prunus spinosa L. fresh fruit using the prepared DES.
• Quantification of TPC, TAC, and AA using spectrophotometric methods.
• Confirmation of DES formation using Fourier-transform infrared spectroscopy (FTIR).
• Optimization of extraction parameters (water content, material amount, extraction time) using Box-Behnken Design (BBD) of response surface methodology (RSM).

Main Results:

• Choline chloride/formic acid (2/1) demonstrated the highest extraction efficiency for TPC, TAC, and AA compared to other DES combinations and conventional solvents.
• FTIR analysis confirmed the successful formation of the ChCl/formic acid DES.
• Optimized conditions using BBD yielded maximum TPC (52.34 mg-GAE/g-FF), TAC (2.09 mg-cyn-3-glu/g-FF), and AA (89.21%).
• Optimal extraction parameters were identified as 50% (v/v) water in DES, 0.833 g of material, and 69.906 s extraction time.

Conclusions:

• Choline chloride/formic acid (2/1) is a highly efficient and promising DES for extracting bioactive compounds from Prunus spinosa L. fresh fruit.
• The optimized DES extraction method offers a superior alternative to traditional solvent systems for natural product isolation.
• This study provides a foundation for the sustainable and efficient utilization of Prunus spinosa L. as a source of valuable phytochemicals.