Effects of γ-irradiation on the biological activity of burdock (Arctium lappa L.) extracts

Effect of extraction methods on the chemical, structural, and rheological attributes of fructan derived from Arctium lappa L. roots

The focus of this study was the evaluation of how extraction techniques impact the chemical, structural, and rheological attributes of fructans extracted from Arctium lappa L. roots. Three distinct extraction procedures were used, utilizing water as solvent, infusion extraction conducted at ambient temperature (25 °C for 5 min), thermal extraction employing reflux (100 °C for 2 h), and ultrasound-assisted extraction (50 °C for 1.38 h with a 158 W output). Chemical characterization by Nuclear Magnetic Resonance (NMR) and colorimetric analyses revealed the obtaining of inulin-type fructans (yield 83 %). The degree of polymerization (DP) was found to be the lowest for ultrasound-assisted extraction (14.38), followed by the room-temperature (20.41) and thermal (21.14) extraction techniques. None of the extraction techniques appeared to modify the molecular structure of the isolated compounds. In X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analyses, distinct crystallization patterns were observed for the room-temperature and thermal extraction techniques, though all fractions consistently exhibited characteristic bands of inulin-type fructan. Rheological assessments indicated a viscoelastic nature of the fractions, with those extracted thermally demonstrating a greater viscosity. This study shows that the choice of extraction method can influence the structural characteristics of inulin-type fructans derived from the burdock root.

Burdock (Arctium lappa L) roots as a source of inulin-type fructans and other bioactive compounds: Current knowledge and future perspectives for food and non-food applications

The roots and tubers of the Asteraceae family are known as a source of various oligosaccharides, and chicory roots and Jerusalem artichoke have stood out for its commercial viability. However burdock root (Arctium lappa L.), which is adapted to temperate climate, moist, and sandy soil, is still unknown as health food in the western world. This review showed the potential of burdock roots as a source of prebiotic fibers, chlorogenic acids, cinnarine, lignans, and quercetin. The extraction methods of burdock functional compounds are made with water, temperature and time variations only. Biological assays showed antioxidant activity, anti-inflammatory, and hypolipidemic properties, and gastric mucosal defense mechanisms, among others. Therefore, the use of burdock roots as functional food should be encouraged in countries that have imported products derived from other roots of the same family for health benefits.