Chemical Composition, Antioxidant, and Antimicrobial Activities of Vetiveria zizanioides (L.) Nash Essential Oil Extracted by Carbon Dioxide Expanded Ethanol

Abstract

In the present study, the composition of essential oil isolated from the roots of Vetiveria zizanioides (L.) Nash, harvested in China, was studied, along with the bioactivities. A green novel method using an eco-friendly solvent, CO2-pressurized ethanol, or carbon dioxide expanded ethanol (CXE) was employed to isolate the essential oil from the root of Vetiveria zizanioides (L.) Nash with the purpose of replacing the traditional method and supercritical fluid extraction (SFE). After investigating the major operating factors of CXE, the optimal conditions were obtained as follows: 8.4 MPa, 50 °C, 5 mL/min ethanol, and 0.22 mole fraction of CO2, presenting an extraction oil that ranged from 5.12% to 7.42%, higher than that of hydrodistillation (HD) or indirect vapor distillation (IVD). The Gas Chromatography-Mass Spectrometry (GC-MS) analysis showed that three major components, including valerenol (18.48%), valerenal (10.21%), and β-Cadinene (6.23%), are found in CXE oil, while a total of 23 components were identified, 48 components less than using conventional hydrodistillation. Furthermore, the antimicrobial activities of root oils were evaluated by the microdilution method, which showed that CXE oil exhibited an ability against Gram-positive bacteria, especially Staphylococcus aureus, approximately equivalent to traditional samples. Additionally, the DPPH free radical scavenging assay demonstrated that the antioxidant abilities of root oils were sorted in the descending order: IVD > HD > CXE > SFE. In conclusion, after a comprehensive comparison with the conventional methods, the CXE-related technique might be a promising green manufacturing pattern for the production of quality vetiver oil, due to the modification of ethanol by the variable addition of non-polar compressible CO2, ultimately resulting in a prominent dissolving capability for the extraction of vetiver solutes.

GC-MS analysis and in silico activity prediction of phytocompounds in the roots of Chrysopogon zizanioides (L.) Roberty

“…Similar findings were reported earlier in the essential oil of C. zizanioides (10)(11)(12). But the methodology followed in this study is simpler and cheaper than other distillation methods followed (13).…”

Encapsulation of Essential Oils for the Development of Biosourced Pesticides with Controlled Release: A Review

“…Conventional methods include hydrodistillation and steam distillation for most plant parts, and cold expression for citrus peel [4]. Some other innovative techniques exist for obtaining the hydrophobic and volatile fraction of plants, such as supercritical carbon dioxide fluid (scCO 2 ) extraction or microwave-assisted extraction [5]. Even if the same fraction is obtained, these products cannot be called EOs, because standard (ISO 9235) reserves this term for products obtained by conventional methods [1,6,7].…”

Essential Oils with High Activity Against Stationary Phase <em>Bartonella Henselae</em>

“…Extracts from Canarium were proved to be active against MRSA and P. aeruginosa [46]. Essential oils of vetiver were active against S. aureus and showed good antifungal and cytotoxic activities [47,48]. And here, for the first time, we identified the remarkable activity of these essential oils active against both log phase and stationary phase B.…”