Essential Oils Extraction Methods, Chemistry and Bioactivities: New Insights and Findings

A special issue of Plants (ISSN 2223-7747). This special issue belongs to the section "Phytochemistry".

Deadline for manuscript submissions: closed (30 June 2023) | Viewed by 33623

Special Issue Editors


E-Mail Website
Guest Editor
Department of Biology, Faculty of Science and Mathematics, University of Montenegro, Džordža Vašingtona bb, 81000 Podgorica, Montenegro
Interests: natural compounds; essential oils and plant extracts; extraction methods and structure elucidation; factors affecting essential oil yield and composition; biological activities research into natural products; influence of secondary metabolites on ecological interactions; medicinal and aromatic plants; pharmacognosy, phytotherapy and ethnobotany
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

There is a myriad of secondary metabolites derived and isolated from various plants. In most cases the biological role of these compounds is not really known. However, they represent a treasure trove of chemistry that can be of both interest and benefit to humans. Essential oils are aromatic, oily liquids extracted from different plant parts. They occur during secondary metabolism, and are normally formed in special cells or cell groups or in glandular hairs found on many leaves and stems. Chemically, a single volatile oil comprises of up to 200 different constituents of terpenoid and non-terpenoid origin, which are synthesized through different biosynthetic routes with distinct primary metabolic precursors. Terpenoids are extremely variable ingredients with different carbon skeletons and a wide variety of oxygenated derivatives; they have gained a particular importance in the synthesis of novel drugs. Phenylpropanoid derivatives are the other important constituent; they are a promising class of bioactive molecules. Essential oil composition varies considerably because of both intrinsic (sexual, seasonal, ontogenetic, and genetic variations) and extrinsic (environmental and ecological aspects) factors. Moreover, it changes in different plant organs and such polymorphisms can also be found between individual plants of a distinct species. Furthermore, the chemical composition depends on the stage of plant development. All these variations may result in the expression of different metabolic pathways, and consequently, quantitative and qualitative variations may occur, leading to the definition of new chemotypes.

This Special Issue welcomes original research and reviews on essential oil extraction methods associated with chemistry and related bioactivities fields. The focus is on the variability of composition in relation to various factors, such as climatic or harvest time, nutritional status, or the isolation method used. New aspects of analysis, chemical characterization, and advancement in the extraction methods are of particular interest, as well as machine learning or artificial intelligence algorithm applications that study the composition–bioactivity correlation.

Dr. Rino Ragno
Dr. Mijat Božović
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Plants is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • essential oil
  • chemotype
  • chemical analysis
  • extraction methods
  • bioactivities
  • terpenoids
  • phenylpropanoids
  • machine learning

Published Papers (10 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

16 pages, 551 KiB  
Article
Efficacy of Lemon Myrtle Essential Oil as a Bio-Fungicide in Inhibiting Citrus Green Mould
by Mohammad M. Rahman, Ronald B. H. Wills, Michael C. Bowyer, Van Q. Vuong, John B. Golding, Timothy Kirkman and Penta Pristijono
Plants 2023, 12(21), 3742; https://doi.org/10.3390/plants12213742 - 31 Oct 2023
Viewed by 1096
Abstract
The effectiveness of lemon myrtle (LM) (Backhousia citriodora) essential oil (EO) was investigated to combat Penicillium digitatum by in vitro agar diffusion and vapour assay and in artificially infected oranges. The main constituent of LM EO was revealed as citral when [...] Read more.
The effectiveness of lemon myrtle (LM) (Backhousia citriodora) essential oil (EO) was investigated to combat Penicillium digitatum by in vitro agar diffusion and vapour assay and in artificially infected oranges. The main constituent of LM EO was revealed as citral when analysed in gas chromatography–mass spectrometry. Pure citral was also included in the experiment for comparison. The in vitro fungal growth was significantly inhibited by LM EO at 1, 2, 3, 4 and 5 μL per disc while complete growth inhibition by both the pure citral and LM EO occurred at 4 and 5 μL per disc. Inoculated fruits treated by dipping in 1000 μL L−1 LM EO solutions for 5, 10, 15, 30 and 120 s showed significantly lower fungal wounds compared to control. While longer dipping times led to some rind injuries, fruits with a 5 and 10 s dip were found free from any injury. The evaluation after dipping and storage confirmed that the fruits maintained the sensory attributes and were not compromised by the incorporation of the essential oil. The results of this study indicate that LM EO can be a promising alternative to synthetic fungicides for preserving the quality of citrus fruits during storage. Full article
Show Figures

Figure 1

16 pages, 313 KiB  
Article
Effect of Different Soil Treatments on Production and Chemical Composition of Essential Oils Extracted from Foeniculum vulgare Mill., Origanum vulgare L. and Thymus vulgaris L.
by Antonio Raffo, Filippo Umberto Sapienza, Roberta Astolfi, Gabriele Lombardi, Caterina Fraschetti, Mijat Božović, Marco Artini, Rosanna Papa, Marika Trecca, Simona Fiorentino, Valerio Vecchiarelli, Claudia Papalini, Laura Selan and Rino Ragno
Plants 2023, 12(15), 2835; https://doi.org/10.3390/plants12152835 - 31 Jul 2023
Cited by 1 | Viewed by 1137
Abstract
The aim of the study was to investigate how essential oil production and associated chemical composition and related biological activity could be influenced by different cultivation treatments and distillation methods. Foeniculum vulgare Mill. (fennel), Origanum vulgare L. (oregano) and Thymus vulgaris L. (thyme) [...] Read more.
The aim of the study was to investigate how essential oil production and associated chemical composition and related biological activity could be influenced by different cultivation treatments and distillation methods. Foeniculum vulgare Mill. (fennel), Origanum vulgare L. (oregano) and Thymus vulgaris L. (thyme) were cultivated in absence of any fertilizer (control) and in presence of three different fertilizers: a chemical one with augmented mineral phosphorus and potassium, a second added with hydrolyzed organic substance and mineral phosphorus and potassium (organic–mineral) and a third one treated with a high content of organic nitrogen of protein origin (organic). The plants were subjected to steam distillation using two modalities, recycled and continuous, to obtain 32 essential oil samples. Chemical composition analysis was performed using gas chromatography–mass spectrometry; in vitro antimicrobial activity was evaluated using a broth microdilution method. In general, the recycled distillation method appeared to have a slightly higher yield than the continuous method. The “mineral” and “organic–mineral” treatments resulted in a higher yield compared to the “organic” or “control” treatments, and this was particularly evident in the recycled method. The “control” plants had a lower yield of essential oils. Anethole (13.9–59.5%) and estragole (13.4–52.2%) were the main constituents of the fennel oils; p-cymene and its derivatives carvacrol and thymol were the main constituents of the oregano and thyme samples. The antimicrobial activity of the thyme oils on Staphylococcus aureus ranged from 0.31 to 0.16% (v/v); a lower effect of the oregano samples and no activity of the fennel samples were observed. The essential oils failed to inhibit the growth of Pseudomonas aeruginosa strains. Full article
17 pages, 3449 KiB  
Article
Comparative GC-MS Analysis of Fresh and Dried Curcuma Essential Oils with Insights into Their Antioxidant and Enzyme Inhibitory Activities
by Nouran M. Fahmy, Shaimaa Fayez, Abdullahi Ibrahim Uba, Mohammad Ali Shariati, Abdullah S. M. Aljohani, Ibrahim M. El-Ashmawy, Gaber El-Saber Batiha, Omayma A. Eldahshan, Abdel Nasser Singab and Gokhan Zengin
Plants 2023, 12(9), 1785; https://doi.org/10.3390/plants12091785 - 27 Apr 2023
Cited by 7 | Viewed by 2301
Abstract
Species belonging to the Zingiberaceae family are of high nutritional, industrial, and medicinal values. In this study, we investigated the effect of processing steps (fresh vs. dried milled rhizomes) and extraction methodologies (hydrodistillation vs. hexane extraction) of curcuma essential oil on its chemical [...] Read more.
Species belonging to the Zingiberaceae family are of high nutritional, industrial, and medicinal values. In this study, we investigated the effect of processing steps (fresh vs. dried milled rhizomes) and extraction methodologies (hydrodistillation vs. hexane extraction) of curcuma essential oil on its chemical content (using GC-MS analysis), its antioxidant behavior (using in vitro assays such as DPPH, ABTS, CUPRAC, FRAP, phosphomolybdenum, and metal chelation), and its enzyme inhibitory activities (on tyrosinase, acetylcholinesterase, butylcholinesterase, α-amylase, and α-glucosidase) supported by multivariate analysis, in silico studies, and molecular dynamics. The GC-MS investigations revealed a high degree of similarity in the chemical profile of fresh hydrodistilled and hexane-extracted essential oils with tumerone and curlone being the major metabolites. The extraction techniques affected the concentrations of other minor constituents such as terpinolene, caryophylla-4(12), 8(13)-dien-5α-ol, and neo-intermedeol, which were almost exclusively detected in the hydrodistilled fresh essential oil; however, zingiberene and β-sesquiphellandrene were predominant in the hexane-extracted fresh essential oil. In the dried curcuma rhizomes, tumerone and curlone contents were significantly reduced, with the former being detected only in the hydrodistilled essential oil while the latter was doubly concentrated in the hexane-derived oil. Constituents such as D-limonene and caryophyllene oxide represented ca. 29% of the dried hydrodistilled essential oil, while ar-turmerone was detected only in the dried hydrodistilled and hexane-extracted essential oils, representing ca. 16% and 26% of the essential oil composition, respectively. These variations in the essential oil chemical content have subsequently affected its antioxidant properties and enzyme inhibitory activities. In silico investigations showed that hydrophobic interactions and hydrogen bonding were the characteristic binding modes of the bioactive metabolites to their respective targets. Molecular dynamics revealed the stability of the ligand-target complex over time. From the current study we conclude that fresh hexane-extracted essential oil showed the best radical scavenging properties, and fresh rhizomes in general display better enzyme inhibitory activity regardless of the extraction technique. Full article
Show Figures

Figure 1

14 pages, 351 KiB  
Article
Study of Cannabis Oils Obtained from Three Varieties of C. sativa and by Two Different Extraction Methods: Phytochemical Characterization and Biological Activities
by Sebastián Pino, Luis Espinoza, Carlos Jara-Gutiérrez, Joan Villena, Andrés F. Olea and Katy Díaz
Plants 2023, 12(9), 1772; https://doi.org/10.3390/plants12091772 - 26 Apr 2023
Cited by 5 | Viewed by 2528
Abstract
Currently, much effort is being placed into obtaining extracts and/or essential oils from Cannabis sativa L. for specific therapeutic purposes or pharmacological compositions. These potential applications depend mainly on the phytochemical composition of the oils, which in turn are determined by the type [...] Read more.
Currently, much effort is being placed into obtaining extracts and/or essential oils from Cannabis sativa L. for specific therapeutic purposes or pharmacological compositions. These potential applications depend mainly on the phytochemical composition of the oils, which in turn are determined by the type of C. sativa and the extraction method used to obtain the oils. In this work, we have evaluated the contents of secondary metabolites, delta-9-tetrahydrocannabinol (THC), and cannabidiol (CBD), in addition to the total phenolic, flavonoids, and anthraquinone content in oils obtained using solid–liquid extraction (SLE) and supercritical fluid extraction (SCF). Different varieties of C. sativa were chosen by using the ratio of THC to CBD concentrations. Additionally, antioxidant, antifungal and anticancer activities on different cancer cell lines were evaluated in vitro. The results indicate that oils extracted by SLE, with high contents of CBD, flavonoids, and phenolic compounds, exhibit a high antioxidant capacity and induce a high decrease in the cell viability of the tested breast cancer cell line (MCF-7). The observed biological activities are attributed to the entourage effect, in which CBD, phenols and flavonoids play a key role. Therefore, it is concluded that the right selection of C. sativa variety and the solvent for SLE extraction method could be used to obtain the optimal oil composition to develop a natural anticancer agent. Full article
13 pages, 1885 KiB  
Article
Extraction of Essential Oils from Lavandula × intermedia ‘Margaret Roberts’ Using Steam Distillation, Hydrodistillation, and Cellulase-Assisted Hydrodistillation: Experimentation and Cost Analysis
by Jessie Wainer, Adrianne Thomas, Tania Chimhau and Kevin G. Harding
Plants 2022, 11(24), 3479; https://doi.org/10.3390/plants11243479 - 12 Dec 2022
Cited by 6 | Viewed by 3322
Abstract
Lavender oil is an important essential oil with many applications. The purpose of this study was to compare different methods of essential oil extraction to determine which method would be the most effective and profitable for commercial-scale production from Lavandula × intermedia (‘Margret [...] Read more.
Lavender oil is an important essential oil with many applications. The purpose of this study was to compare different methods of essential oil extraction to determine which method would be the most effective and profitable for commercial-scale production from Lavandula × intermedia (‘Margret Roberts’) flowers and leaves. The lavender from this variety flowers year-round, providing an extended production season compared to some other lavender varieties. Steam distillation, hydrodistillation, and cellulase-assisted hydrodistillation were used to extract oil. The average extraction times for steam distillation, hydrodistillation, and cellulase-assisted hydrodistillation were 57-, 51-, and 49 min, respectively, and the average energy consumption was 15.0-, 13.4-, and 30.8 kJ/g, respectively. Cellulase-assisted hydrodistillation produced the best quality oils, with a lower camphor content and a sweeter, more pleasant smell, while steam-distilled oils had the highest camphor content, as well as a more plant-like smell. Factors affecting scale-up (surface area of cut plants, equipment loading times, energy efficiencies, safety, mixing) have been discussed, while a basic cost analysis of theoretical large-scale processes showed that hydrodistillation and cellulase-assisted hydrodistillation would be the most and least profitable methods, respectively. Overall, hydrodistillation is recommended as the best method for commercial lavender oil production. Full article
Show Figures

Figure 1

13 pages, 20663 KiB  
Article
Bioprospecting of Essential Oil-Bearing Plants: Rapid Screening of Volatile Organic Compounds Using Headspace Bubble-in-Drop Single-Drop Microextraction for Gas Chromatography Analysis
by Thabiso E. Letseka, Ntjana J. Sepheka, Ian A. Dubery and Mosotho J. George
Plants 2022, 11(20), 2749; https://doi.org/10.3390/plants11202749 - 17 Oct 2022
Viewed by 1794
Abstract
Essential oils are vital constituents of oil-bearing plants. However, their screening still demands harvesting of the plant for laboratory analysis. We report herein a simple, rapid and robust headspace bubble-in-drop microextraction screening technique (BID-SPME) requiring only small amounts of plant material. The optimised [...] Read more.
Essential oils are vital constituents of oil-bearing plants. However, their screening still demands harvesting of the plant for laboratory analysis. We report herein a simple, rapid and robust headspace bubble-in-drop microextraction screening technique (BID-SPME) requiring only small amounts of plant material. The optimised method uses 0.5 g of the crushed plant leaves sample obtained in a 2 mL capped chromatography vial, heated to 55 °C and sampled with 2 µL heptadecane in a Hamilton gastight syringe equilibrated for 15 min exposed to the headspace volume. The method was applied to three plants, Pinus radiata, Tagetes minuta and Artemisia afra, which are known for their essential oil content. The method was able to extract at least 80% of the oil constituents in such abundance that they could be easily annotated using the gas chromatography–mass spectrometry (GC–MS) mass spectral libraries. The major volatile organic compounds (VOCs) detected included tagetone, terpinen-4-ol, ocimenone, caryophyllene, dihydrotagetone, terpinolene and artemisia ketone, just to mention a few, at different concentrations in different plants. Importantly, these annotated VOCs were also reported in other studies in the same and even different plants, extracted using normal steam distillation and importantly those reported in the literature for different extraction techniques. Full article
Show Figures

Figure 1

11 pages, 388 KiB  
Article
Authentication and Market Survey of Sweet Birch (Betula lenta L.) Essential Oil
by Noura S. Dosoky, Ambika Poudel and Prabodh Satyal
Plants 2022, 11(16), 2132; https://doi.org/10.3390/plants11162132 - 16 Aug 2022
Cited by 3 | Viewed by 10608
Abstract
Sweet Birch (Betula lenta) has several economic and medicinal uses. Very little is known about the chemical composition of B. lenta. In this study, the volatile compositions of the bark of B. lenta from authentic and commercial sources were assessed [...] Read more.
Sweet Birch (Betula lenta) has several economic and medicinal uses. Very little is known about the chemical composition of B. lenta. In this study, the volatile compositions of the bark of B. lenta from authentic and commercial sources were assessed by gas chromatography-mass spectrometry (GC–MS) and gas chromatography–flame ionization detection (GC–FID). Overall, more than 60 compounds were identified in natural sweet birch EO obtained by hydro-distillation. The oil was dominated by methyl salicylate (93.24–99.84%). A good approach to distinguishing wintergreen and birch oils would be biomarker-based analysis. The biomarkers are selected based upon three main criteria: (1) the marker should be commercially unavailable or too expensive which renders the adulteration process very costly, (2) The marker should be detected consistently in all the tested authentic EO samples, and (3) A birch EO marker should be found exclusively in birch EO, not in wintergreen and vice versa. The minor components o-guaiacol, veratrole, 2-E-4-Z-decadienal, and 2-E-4-E-decadienal were identified as natural marker compounds for authentic sweet birch oil. Surprisingly, none of the tested 27 commercial samples contained any of the identified birch markers. The detection of wintergreen markers such as vitispirane and β-dehydroelsholtzia ketone, the synthetic marker dimethyl-2-hydroxyterephthalate, and ricenalidic acid lactone suggest the addition of wintergreen, synthetic methyl salicylate, and castor oil, respectively. This is the first report to identify birch biomarkers to the best of our knowledge. Full article
Show Figures

Graphical abstract

17 pages, 1483 KiB  
Article
Photoprotective Agents Obtained from Aromatic Plants Grown in Colombia: Total Phenolic Content, Antioxidant Activity, and Assessment of Cytotoxic Potential in Cancer Cell Lines of Cymbopogon flexuosus L. and Tagetes lucida Cav. Essential Oils
by Karina Caballero-Gallardo, Patricia Quintero-Rincón, Elena E. Stashenko and Jesus Olivero-Verbel
Plants 2022, 11(13), 1693; https://doi.org/10.3390/plants11131693 - 27 Jun 2022
Cited by 13 | Viewed by 2769
Abstract
Photoprotective agents obtained from plants provide benefits for the health of the skin. The present study aims to assess the total phenolic content (TPC) and in vitro UV-protective properties of twelve essential oils (EOs) from plants grown in Colombia and to evaluate the [...] Read more.
Photoprotective agents obtained from plants provide benefits for the health of the skin. The present study aims to assess the total phenolic content (TPC) and in vitro UV-protective properties of twelve essential oils (EOs) from plants grown in Colombia and to evaluate the antioxidant and cytotoxic potential of two species identified as photoprotective potentials: Cymbopogon flexuosus and Tagetes lucida. The composition of EOs was studied by GC/MS. The cytotoxicity of both EOs was examined using an MTT assay, and an H2-DCFDA probe was employed to estimate the intracellular production of ROS in HepG2 and Calu-1 cells. Major constituents (≥10%) were neral, geranial, geranyl acetate in C. flexuosus and estragole in T. lucida. The TPC for C. flexuosus and T. lucida EOs were ≥10 mg GAE/g of byproduct. Both EOs showed photoprotective properties (SPFin vitro: 13–14), and long-wavelength UVA protection (λc > 370 nm). HepG2 and Calu-1 cells exposed to C. flexuosus exhibited antiproliferative activity (˂50%) at 125 µg/mL, while T. lucida was at 250 and 500 µg/mL. The IC50 values for C. flexuosus were 75 and 100 µg/mL in HepG2 and Calu-1 cells, respectively, whereas those for T. lucida were >250 µg/mL. These EOs achieved significant inhibitory effects (between 15.6 and 40.4%) against H2O2-induced oxidative stress. The results showed that EO compounds recognized as antioxidants could counteract the effects elicited by H2O2. Full article
Show Figures

Figure 1

16 pages, 5846 KiB  
Article
Hydrodistillation and Microwave Extraction of Volatile Compounds: Comparing Data for Twenty-One Veronica Species from Different Habitats
by Valerija Dunkić, Marija Nazlić, Mirko Ruščić, Elma Vuko, Karla Akrap, Snježana Topić, Milenko Milović, Nenad Vuletić, Jasna Puizina, Renata Jurišić Grubešić, Siniša Srečec and Dario Kremer
Plants 2022, 11(7), 902; https://doi.org/10.3390/plants11070902 - 28 Mar 2022
Cited by 6 | Viewed by 1851
Abstract
Free volatile compounds were isolated from 21 Croatian Veronica species studied by hydrodistillation (HD) and microwave extraction (ME) and analyzed by gas chromatography coupled with mass spectrometry. Principal Component Analysis (PCA) distinguished some clusters based on the relative proportion of major compounds, such [...] Read more.
Free volatile compounds were isolated from 21 Croatian Veronica species studied by hydrodistillation (HD) and microwave extraction (ME) and analyzed by gas chromatography coupled with mass spectrometry. Principal Component Analysis (PCA) distinguished some clusters based on the relative proportion of major compounds, such as hexadecanoic acid, hexahydrofarnesyl acetone, phytol, E-caryophyllene, and caryophyllene oxide, which were identified in all species studied by both isolation methods. In addition to these compounds, germacrene D, δ-selinene, and eicosane were also identified in five samples from dry habitats isolated using ME. Allo-aromadendrene and β-ionone are particularly abundant in five species from wet habitats isolated by both methods. The peculiarities of Veronica species from moderate habitats isolated with HD are benzene acetaldehyde, n-nonanal, and the identification of significant compounds from the hydrocarbon class, while the peculiarity of ME is (E)-β-damascenone. In this article, we present new results on the phytochemical characterization of Veronica species from different habitats. The biological potential of these compounds should be further investigated for a better understanding and utilization of the specialized plant metabolites. Full article
Show Figures

Figure 1

11 pages, 524 KiB  
Article
Foeniculum vulgare Miller, a New Chemotype from Montenegro
by Mijat Božović, Stefania Garzoli, Svetlana Vujović, Filippo Sapienza and Rino Ragno
Plants 2022, 11(1), 42; https://doi.org/10.3390/plants11010042 - 23 Dec 2021
Cited by 6 | Viewed by 3302
Abstract
Previous studies relating to prolonged and fractionated distillation procedures highlighted essential oils’ (EOs) chemical composition to be significantly dependent on the extraction duration and harvesting time. As a continuation, a hydrodistillation procedure was applied to ripe fruit material of fennel, Foeniculum vulgare Miller [...] Read more.
Previous studies relating to prolonged and fractionated distillation procedures highlighted essential oils’ (EOs) chemical composition to be significantly dependent on the extraction duration and harvesting time. As a continuation, a hydrodistillation procedure was applied to ripe fruit material of fennel, Foeniculum vulgare Miller (Apiaceae), collected from three localities in Montenegro (Podgorica, Nikšić, and Kotor) to furnish a total of 12 EOs. Liquid and vapor phases of the samples were analyzed by Gas Chromatography/Mass Spectrometry and Headspace-Gas Chromatography/Mass Spectrometry techniques, and 18 compounds have been identified. Although both quantitative and qualitative differences between the samples were notable, the phenylpropanoids anethole (ANE) and estragole and the monoterpenoids α-terpineol (TER) and fenchone (FEN) could be singled out as the most abundant constituents. The EOs from Podgorica belong to the most common ANE-rich chemotype, while the predominance of the monoterpenoid fraction is characteristic of the samples from Nikšić and Kotor. The latter is particularly rich in TER (up to 56.5%), with significant amounts of FEN and ANE. This chemical profile could represent a new chemotype of fennel EO. Vapor phases contained mainly monoterpenoids, with increased amounts of FEN and TER, while the number of phenylpropanoids was significantly decreased. Full article
Show Figures

Figure 1

Back to TopTop