Artemisia annua L. is known for producing artemisinin, a sesquiterpene lactone compound, which is applied to treat of malaria [1]. Its pharmacodynamic and pharmacokinetic characteristics, as well as its strong capacity for Plasmodium elimination, have raised many expectations for this new class of antimalarial drugs [2]. However, this plant has been also used in traditional Chinese medicine to treat of various diseases since ancient times. Recent studies have focused on its extensive biological activities, which makes this plant an excellent candidate to be used in clinical therapies. Thus, this work aimed to evaluate different bioactivities from a hydroethanolic extract of Artemisia annua.
The plant extract in ethanol:water (80:20 v/v) was obtained by microwave-assisted extraction. The antioxidant activity was determined by thiobarbituric acid reactive substances (TBARS) assay, showing a potent activity with an IC50 of 10.3 ± 1.0 μg/mL. A. annua L. extract also exhibited antibacterial and antifungal properties, with concentrations ranging from 2.5 to 10 mg/mL. The ethanolic extract was very effective against the four tumor cell lines, presenting GI50 ranging from 21 to 61 μg/mL and excellent anti-inflammatory activity (38 μg/mL). However, it was also cytotoxic against the two normal cells tested (50 and 19 μg/mL).
Concluding, despite the excellent biological activities exhibited by A. annua L. extract, it was also demonstrated to be cytotoxic against normal cells. Therefore, further studies are necessary to study how the cytotoxicity of this extract could be reduced without affecting its bioactive properties.
Ultrasound-assisted extraction (UAE) was used to recover hydroxytyrosol and tyrosol from olive pomace, a residue generated by the olive oil industry. The extraction process was optimized using response surface methodology (RSM), with processing time, ethanol concentration and ultrasonic power as the combined independent variables. The highest amounts of hydroxytyrosol (36 +/- 2 mg g(-1) of extract) and tyrosol (14 +/- 1 mg g(-1) of extract) were obtained after 28 min of sonication at 490 W using 7.3% ethanol as the solvent. Under these global conditions, an extraction yield of 30 +/- 2% was achieved. The bioactivity of the extract obtained under optimized UAE was evaluated and compared with that of an extract obtained under optimal heat-assisted extraction (HAE) conditions in a previous work of the authors. Compared to HAE, UAE reduced the extraction time and the solvent consumption, and also led to higher extraction yields (HAE yield was 13.7%). Despite this, HAE extract presented higher antioxidant, antidiabetic, anti-inflammatory and antibacterial activities and no antifungal potential against C. albicans. Furthermore, HAE extract also showed higher cytotoxic effects against the breast adenocarcinoma (MCF-7) cell line. These findings provide useful information for the food and pharmaceutical industries in developing new bioactive ingredients, which may represent a sustainable alternative to synthetic preservatives and/or additives.
