Advanced Analytical Approaches for the Analysis of Polyphenols in Plants Matrices—A Review

Abstract

Phenolic compounds are plants’ bioactive metabolites that have been studied for their ability to confer extensive benefits to human health. As currently there is an increased interest in natural compounds identification and characterization, new analytical methods based on advanced technologies have been developed. This paper summarizes current advances in the state of the art for polyphenols identification and quantification. Analytical techniques ranging from high-pressure liquid chromatography to hyphenated spectrometric methods are discussed. The topic of high-resolution mass spectrometry, from targeted quantification to untargeted comprehensive chemical profiling, is particularly addressed. Structure elucidation is one of the important steps for natural products research. Mass spectral data handling approaches, including acquisition mode selection, accurate mass measurements, elemental composition, mass spectral library search algorithms and structure confirmation through mass fragmentation pathways, are discussed.

Sustainable Extraction Techniques for Obtaining Antioxidant and Anti-Inflammatory Compounds from the Lamiaceae and Asteraceae Species

“…A corresponding solvent volume of ethanol or ethanol:water (50:50, v/v) was added to 35 g of ground plant material in a ratio of 1:10 (plant/solvent, w/v). The mixture was submitted to ultrasounds for 30 min and 70% amplitude using a probe of 1 2 diameter. Next, samples were filtered, and ethanol was removed under vacuum at 30 • C (IKA RV 10, Madrid, Spain).…”

“…In the last decades, an increasing number of studies have focused on finding new sources of food ingredients for applications in pharmaceuticals, cosmetics, the food industry and, of course, nutrition [1]. Several compounds, such as phenolic compounds, terpenes, carotenoids, saponins and peptides are considered to possess interesting biological activities [2].…”

“…Extracts from marjoram, including its essential oil, have been reported to possess antimicrobial, antioxidant, anti-proliferative and anti-inflammatory activities [4,6]. Caffeic acid derivatives and flavonoids, along with ursolic acid, carvacrol and terpineol, have been associated with these biological activities [1,6].…”

“…For that purpose, extraction techniques run by the Green Chemistry principles should be used. Supercritical Fluid Extraction (SFE) has been widely used for the extraction of hydrophobic compounds in a more efficient and green environment [1]. SFE primarily uses CO 2 as carrier, as well as a green and GRAS (Generally Recognized as Safe) solvent, which allows the recovery of high-quality extracts.…”

“…nd, not detected. < LOQ, below limit of quantification 1. Indicates statistical differences between MIL-50 and MIL-100 extracts (p < 0.05).…”