engleski

A comparative study on different extraction techniques for recovery of bioactive compounds from sweet wormwood (Artemisia annua L.)

Introduction: Sweet wormwood (Artemisia annua L.) is a plant rich in bioactive compounds including flavonoids, coumarins, steroids, monoterpenoids, triterpenoids and sesquiterpenoids with unique pharmacological properties. Artemisinin has been recognized as the main bioactive compound in sweet wormwood and has been widely studied for its effectiveness against causative agents of malaria, in the treatment of pneumonia in AIDS and other immune-compromised patients and treatment of different parasites (causative agents of toxoplasmosis). Lately, it has been recognized for antiviral activity against COVID-19 disease. The pharmacological activity of Artemisinin and its derivates is based on inhibition of the enzymatic activity of chymotrypsin-like protease which is an enzyme produced by SARS-CoV-2. Moreover, due anti- inflammatory activity of Artemisinin, it is possible to reduce the systemic levels of inflammatory cytokines that contribute to cytokine storm and inflammatory organ injury in high-risk COVID-19 patients. Objectives and task: This study aimed to compare different extraction techniques: supercritical CO2 (SC- CO2) extraction, subcritical water extraction (SWE), extraction with deep eutectic solvents (DES) and ultrasound- assisted extraction (UAE) for recovery of Artemisinin and Artemisinin derivates. Since non- polar extracts are rich in volatile compounds, this study also intends to determine the volatile profile of obtained non- polar extracts (SC-CO2) to examine possible contribution of volatile organic compounds in health benefits of sweet wormwood extracts. Method of work: UAE was performed at three different temperatures (30, 50 and 70°C) during the three treatment times (15, 30 and 45 min) and the three solvent/solid ratios (10, 20 and 30 mL/g). with a nominal power of 50 W and a frequency of 37 kHz. SWE was performed at four temperatures (125, 150, 175 and 200°C) during the time of 15 min and extraction pressure of 30 bar. SC-CO2 extraction was performed at a pressure of 300 bar, the temperature of 40°C and the CO2 flow of 1.4 kg/h. Extraction using different DESs was done with 20% water (v/v) at a temperature of 30, 50 and 70°C for one hour. Analyses of extracts were performed using high- performance liquid chromatography (HPLC) and gas chromatography with mass spectrometry (GC- MS). Results: HPLC analysis showed that Artemisinin was not extracted using SWE, while SC-CO2, UAE and certain DESs were suitable for Artemisinin extraction. In extracts obtained using UAE, the results ranged from 0 to 2.23 μg/mg of plant, while the values for DESs consisted of choline chloride: lactic acid (1:2) and choline chloride: levulinic acid (1:2), depending on the temperature, range from 1.03 to 1.70 μg/mg of plant. In the case of extraction using SC- CO2, 3.21 μg/mg of the plant was extracted. The highest Artemisinin content was found in SC- CO2obtained under the following conditions: 300 bar, 40°C and the CO2 flow of 1.4 kg/h. SC- CO2 extract of sweet wormwood was characterized with a high level of Arteannuin b (15.29%), Camphor (12.23%) and Artemisia ketone (10.97%). Conclusion: Given the proven antiviral properties of Artemisinin and its derivatives is important to establish safe and efficient extraction techniques for pharmacological purposes. This study provides a useful insight into four extraction techniques and their influence on Artemisinin recovery. Overall, the present study contributes toward better chemical characterization of sweet wormwood as an important source of bioactive compounds.

Artemisinin ; green extraction techniques ; sweet wormwood ; Artemisia annua

nije evidentirano