Analytical methods to determine phenolic compounds and antioxidant activity in artichoke (Cynara cardunculus L. var. scolymus)

Abstract

Objective: To describe the main analytical methods used for the determination and quantification of polyphenols in artichoke (Cynara cardunculus L. var. scolymus). Methodology: A bibliographic review was conducted using specialized databases such as Medline, PubMed, CIMA, Google Scholar, ScienceDirect, and Scielo. The search terms included keywords related to cultivation, maturation, extraction, and analysis of phenolic compounds in artichoke, as well as its antioxidant capacity. Results: The advances of the last seven years in the qualitative-quantitative determination of phenolic compounds in artichoke are highlighted. The most recent strategies for the extraction of target compounds from artichoke are mentioned along with the analytical approaches adopted for the separation, identification and quantification of phenolic acids, flavonoids, anthocyanins and total condensed tannins. The main characteristics of “traditional” extraction methods (maceration and ultrasonic-assisted extraction) are described, as well as the most innovative protocols that involve advanced extraction techniques, such as microwave-assisted extraction (MAE). The predominant role of HPLC in defining the phenolic profile is examined and the most recent results obtained through the use of mass spectrometry-based detection systems are presented. Likewise, the most common procedures aimed at evaluating the antioxidant properties of artichoke phenolic extracts are described. Conclusion: Considerable progress has been made in the identification of the chemical structures of artichoke bioactive compounds, techniques based on mass spectrometry represent a powerful tool to define the phenolic profile of artichoke, although there's a lack of complete validation protocols for most of the proposed procedures.