Comparison of different green‐extraction techniques and determination of the phytochemical profile and antioxidant activity of Echinacea angustifolia L. extracts

Abstract

Introduction Nowadays several plant species, such as Echinacea angustifolia L., can be considered natural important sources for therapeutic applications. Echinacea angustifolia is one of the most known medicinal plants, it shows protective and preventive effects against many chronic diseases, thanks to immunostimulant properties, mostly due to its polysaccharides and antioxidants. However, the optimisation of green extraction techniques to respect the environment is, currently, a hard challenge for the recovery of secondary metabolites. Methodology Hydro‐enzymatic extraction has been performed for the first time, it was compared with other different extraction techniques, for their efficacy in bioactive compound recovery. Phytochemical characterisation has been carried out through high‐performance liquid chromatography diode array detector (HPLC‐DAD) analysis and the antioxidant activity has been also measured. Results The highest extractive yields and the strongest antioxidant activity was obtained by cellulase and xylanase enzyme extraction. The enzymatic extraction with pectinase enzyme led to a higher polysaccharide content in comparison with the literature. The hydro‐enzymatic extraction method and analytical conditions allowed the identification and quantification of two compounds, to the best of our knowledge, for the first time in E. angustifolia root extract. Conclusion The optimised extraction methods discussed in this work led to a higher polysaccharides content, in comparison to previous literature results. The enzymatic extraction seems to be the best extraction technique, in terms of antioxidant yield and efficacy in bioactive compound recovery.

Influence of different extraction techniques on recovery, purity, antioxidant activities, and microstructure of flaxseed gum

“…It was noticed from the results that the yield, carbohydrate, and protein contents were significantly influenced by the extraction temperatures ( P < 0.05). Extraction yield of FSG at room temperature (approximately 20°C) was observed as 2.82% and increased from 3.73% to 8.92% with rising temperature from 40 to 100 °C, which can be attributed to the reason that rising temperature increased the solute solubility in the solvent, accelerating the diffusion rate, leading to a higher mass transfer rate, and as a result improving the yield efficiency (He et al., 2018; Russo et al., 2019). Flaxseed gum mainly exists in the outermost layer of the seed, that is, epidermis, and the gum is released when the seeds are dispersed in water, gum cells on the seed coat get swell, and their content appears on the seed surface (Kaewmanee et al., 2014).…”

Comparison of Maceration and Ultrasonication for Green Extraction of Phenolic Acids from Echinacea purpurea Aerial Parts

“…This is not surprising, because caffeic acid derivatives are not the only substances with radical scavenging abilities in E. purpurea. Various other phytochemicals, which were not determined within scope of this work but are present in E. purpurea, such as phylloxanthobilins [32] and polysaccharides [33], may act as strong antioxidants and free radical scavengers.…”

New Insights into the Exploitation of Vitis vinifera L. cv. Aglianico Leaf Extracts for Nutraceutical Purposes

“…Conventional (maceration, Soxhlet extraction) and non-conventional (ultrasound-assisted, microwave-assisted, accelerated solvent and subcritical water extraction techniques) approaches can be applied [ 3 ]. Extraction method effectiveness is evident when different methods are practiced on the same plant matrices by using the same solvent and extraction efficiency shows significant variations [ 4 ]. The extraction methods should be optimized not only for its total phytochemical profile but also for its biological effects.…”