Ultrasound and Microwave-Assisted Extraction of Elecampane (Inula helenium) Roots

Abstract

The aim of the current research was to perform two "green chemistry" extractions (ultrasound and microwave irradiation) with methanol, 70% (v/v) ethanol and water for extraction of biologically active substances from elecampane (Inula helenium L.) roots and to compare their contents in all extracts. The presence of carbohydrates (sugars, fructooligosaccharides and inulin), total phenols and flavonoids were established. In vitro antioxidant potential was also evaluated by four assays (DPPH, ABTS, FRAP and CUPRAC). Water extracts obtained by ultrasound-assisted extraction (UAE) showed the highest value of inulin (38 g/100 g dry weight plant material). The highest antioxidant activity was possessed by the 70% (v/v) ethanol extracts obtained by UAE: DPPH-107.2 mM TE/g dw, ABTS-86.0 mM TE/g dw, FRAP-67.0 mM TE/g dw and CUPRAC-173.0 mM TE/g dw, respectively. The reason for this probably depended on the highest content of total phenols in the 70% UAE ethanol extract {7.9 mg GAE/g dw, phenolic acids (chlorogenic, caffeic, p-coumaric, sinapic and ferulic acids)}, especially chlorogenic acid (1.84 mg/g) and flavonoids (quercetin, kaempferol and catechin; 26.4 mg QE/g dw). UAE was evaluated as a promising approach for the simultaneous extraction of bioactive compounds (dietary fibers and antioxidants) from elecampane roots in comparison with microwave irradiation.

Comparison of enzymatic and microwave‐assisted alkaline extraction approaches for the generation of oligosaccharides from American Cranberry (Vaccinium macrocarpon) Pomace

“…(2015) have demonstrated that cranberry proanthocyanidins and other polyphenols exhibited anti‐infective properties, whereas oligosaccharide components in cranberry showed an anti‐biofilm effect against Escherichia coli biofilm. Owing to the fact that conventional extraction can lead to the use of large amount of solvents, energy, time, and generation of carbon footprints, there has been an increased focus on green technologies for extraction of functional ingredients (Khodaei, Karboune, & Orsat, 2016; Mtetwa et al., 2020; Petkova, Ivanov, Vrancheva, Denev, & Pavlov, 2017). This work is aimed at the extraction of cell wall carbohydrates (e.g., pectic oligo/polysaccharides) from cranberry pomace obtained from industrial juice production using the microwave‐assisted alkaline extraction and the enzymatic approaches.…”

Optimization of ultrasonic–microwave synergistic extraction of flavonoids from sweet potato leaves by response surface methodology

“…The biggest advantage of MAE is time‐saving, compared to 2 hr of conventional reflux extraction of total polyphenols from the leaves of Pistacia lentiscus , the MAE could only take 60 s to attain the highest yield of total polyphenols, saving more than 99% of the time (Dahmoune et al, ). Meanwhile, the highest antioxidant activity could be obtained in 70% ethanol extracts from elecampane ( Inula helenium ) roots collected by UAE which was 86.0 mM TE/g DW in ABTS and 67.0 mM TE/g DW in ferric reducing antioxidant power (FRAP) (Petkova, Ivanov, Vrancheva, Denev, & Pavlov, ).…”

Chain length distribution of inulin from dahlia tubers as influenced by the extraction method

“…Several methods of obtaining inulin from various materials of Asteraceae plants have been thus far published, including ultrasonic-and microwave-supported techniques. [25,30,43,44] The extraction Figure 2. HPAEC-PAD analysis of dahlia inulins, obtained by purification method pur 3; three elution methods were used as indicated: A -sep1; B -sep2; C -sep3 (for details see Table 1).…”