A study on the essential oil of Ferulago campestris: How much does extraction method influence the oil composition?

The essential oil of different parts of Ferulago campestris (Bess.) collected in Sicily has been extracted by microwave-assisted hydrodistillation (MAHD) and by classic hydrodistillation (HD). A comparative qualitative-quantitative study on the composition of the oils was carried out. A total of 100 compounds were identified in the oils obtained by MAHD, whereas 88 compounds characterized the HD oils. The most prominent components were, in all different parts of F. campestris and in both extraction methods, 2,4,5-trimethylbenzaldehyde and 2,4,6-trimethylbenzaldehyde isomers; the latter was not previously found. The attempt to evaluate where the oil components are located in all parts of the plant was carried out by means of a kinetic study. Then, electron microscopy observation on the different parts before and after MAHD and HD was performed.     

Comparison of microwave-assisted and conventional hydrodistillation in the extraction of essential oils from mango (Mangifera indica L.) flowers

Microwave-assisted hydrodistillation (MAHD) is an advanced hydrodistillation (HD) technique, in which a microwave oven is used in the extraction process. MAHD and HD methods have been compared and evaluated for their effectiveness in the isolation of essential oils from fresh mango (Mangifera indica L.) flowers. MAHD offers important advantages over HD in terms of energy savings and extraction time (75 min against 4 h). The composition of the extracted essential oils was investigated by GC-FID and GC-MS. Results indicate that the use of microwave irradiation did not adversely influence the composition of the essential oils. MAHD was also found to be a green technology.     

Optimization of microwave-assisted hydro-distillation essential oil extracted from Rumex Crispus leaves using definitive screening design

Conversion of nonfood natural products to value-added products is an important work, which is going on worldwide. In addition, to obtain a product with better quality, a sufficient separation method is helpful to improve its utilization value by using effective, rapid and environmentally friendly techniques. Thus in this work, the microwave-assisted hydrodistillation (MAHD) process of essential oils from important natural plant Rumex Crispus leaves was investigated. The experimental design and extraction conditions were optimized using a definitive screening design. The yield of essential oils of 4.67 ± 0.02 % was investigated under the optimum conditions; 534.89 W of microwave power, 23.48 min of hydrodistillation time and 4.5 mL/g of the volume of water to plant mass ratio. Under these conditions, the essential oils were analyzed using gas chromatography-mass spectrometry (GC–MS). Results revealed that the essential oil extracted by MAHD possessed high quality as proved by its higher percentage of oxygenated compounds. In addition, α-santol (29.63 %) and β-santol (25.60 %) are the primary components of oxygenated compounds in essential oils. In conclusion, the MAHD was successfully employed to obtain mainly Oxygenated compounds-rich essential oil that may be used in several industrial applications. Subsequently, a definitive screening design may be regarded as an alternative and reliable method for the prediction of experimental parameters. It was concluded that the weeds plant (Rumex Crispus) contains a reliable quantity of oils that is extremely feasible to use and recommended as good feedstock for possible use in industrial applications.     

Comparative study of chemical composition,antibacterial and antioxidant activity of essential oils isolated from the seeds of Amomum subulatum by using microwave extraction and hydro-distillation methods

Microwave assisted hydro-distillation (MAHD) and conventional hydro-distillation (HD) techniques were compared in the extraction of essential oils from Amomum subulatum seeds. The time required for MAHD method (70 ​min) is lesser than that for HD method (4 ​h). There is a slight increase in the yield of extracted oil in MAHD method (3.35%) compared to HD (3%). Gas chromatography–mass spectrometry GC-MS results show that MAHD extracted essential oil was wealthier in oxygenated compounds. 1, 8-Cineole was found to be a major compound in case of both the essential oil, followed by α-pinene. In MAHD the percentage of the major oxygenated monoterpene (1, 8- cineol) slightly increases from 88% to 89% as compared to hydrodistillation. Contrarily to this, the percentage of monoterpene hydrocarbon was decreased in MAHD than HD extracted oil. MAHD and HD extracted oils show good antibacterial activities against gram-negative and gram-positive bacteria. MAHD extracted oil shows better antibacterial activity than HD extracted against both gram positive and gram-negative bacteria. 2, 2-diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging antioxidant activities show that MAHD extract has better inhibition percentage than HD extract, and the half-maximal inhibitory concentration IC50 value of MAHD was less than HD extracted oil.     

Phytochemical Investigation by Microwave‐Assisted Extraction of Essential Oil of the Leaves of Walnut Cultivated in Algeria

Walnut (Juglans regia L.) leaves are used traditionally as an herbal tea indicated for non‐insulin‐dependent diabetics. In recent years, the type‐II diabetes is occurring worldwide with increasing frequency. Thus, there is an urgent need to explore the new beneficial biomolecules on the human health. Our objective was to investigate, for the first time, the volatiles profile of Juglans regia L. leaves from Algiers region. The extraction of essential oil of fresh plant material was performed by microwave‐assisted hydrodistillation (MAHD), for the first time, a relatively recent method, then by the conventional hydrodistillation technique (HD) for comparison. The collected extracts were analyzed by GC‐FID and GC/MS using two capillary columns with different polarity. Extraction time of 1 h by MAHD provided higher yields (0.050±0.001% (w/w)) than by HD (0.030±0.006% (w/w)) after 3 h. A total of 38 compounds were identified using both techniques. Essential oils had similar qualitative but different quantitative composition in terms of chemical compounds. The MAHD method improved yield while reducing the extraction time. The sesquiterpenes were the dominant family in both MAHD and HD essential oils with β‐caryophyllene being the major constituent. Monoterpenes, including hydrocarbon and oxygenated, prevail in HD volatile fraction with β‐pinene and eucalyptol, respectively, as major components.     

Variability of essential oils of Betonica officinalis (Lamiaceae) from different wild populations in Kosovo

The aerial parts and roots of Betonica officinalis were collected from three localities characterized by different ecological conditions to study the natural variability of the chemical composition of the essential oils in this plant. The leaves and inflorescences were collected during the flowering time, whereas the roots were collected at the end of the vegetative period. The plant material was dried at room temperature. The essential oils were obtained by micro-steam hydrodistillation and analyzed using gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Overall, 69 constituents were identified in all localities and plant parts. The main compositions of the leaves in all localities were alpha-pinene, 1-octen-3-ol, beta-bourbonene, (E)-caryophyllene and germacrene D. The essential oil of the inflorescences was characterized by these main constituents: alpha-pinene, (E)-caryophyllene and trans-beta-farnesene. In all localities, the percentages of alpha-pinene and (E)-caryophyllene were higher in the inflorescences than in the leaves, whereas nonane was the main constituent in the roots.     

Chemical composition and antifungal activity of essential oils of Thuja sutchuenensis, a critically endangered species endemic to China

The essential oils from leaves, twigs and stems of large trees and shrub-like trees of Thuja sutchuenensis were extracted by hydrodistillation and supercritical fluid extraction, and analyzed by GC and GC-MS. The essential oil composition differed significantly among the three organs, as well as between large trees and shrub-like trees. Furthermore, consistent with the eastern Asia-North American disjunct distribution of the genus, many differences in the essential oil composition between T. sutchuenensis and other Thuja species were apparent. The essential oils exhibited a certain degree of antifungal activity against six strains of human pathogenic fungi.     

Rapid analysis of the essential oils from dried Illicium verum Hook. f. and Zingiber officinale Rosc. by improved solvent-free microwave extraction with three types of microwave-absorption medium

A new method of extracting essential oils from dried plant materials has been studied. By adding a microwave-absorption medium (MAM) to a reactor, solvent-free microwave extraction (SFME) was improved and can be used to extract essential oils from dried plant material without pretreatment. With a microwave irradiation power of 85 W it took only approximately 30 min to extract the essential oils completely. The whole extraction process is simple, rapid, and economical. Three types of MAM, iron carbonyl powder (ICP), graphite powder (GP), and activated carbon powder (ACP), and two types of dried plant material, Illicium verum Hook. f. and Zingiber officinale Rosc., were studied. The results were compared with those obtained by use of conventional SFME, microwave-assisted hydrodistillation (MAHD), and conventional hydrodistillation (HD), and the conclusion drawn was that improved SFME was a feasible means of extracting essential oils from dried plant materials, because there were few differences between the composition of the essential oils extracted by improved SFME and by the other methods.     

Improved solvent-free microwave extraction of essential oil from dried Cuminum cyminum L. and Zanthoxylum bungeanum Maxim

Solvent-free microwave extraction (SFME) is a recently developed green technique which is performed in atmospheric conditions without adding any solvent or water. SFME has already been applied to extraction of essential oil from fresh plant materials or dried materials prior moistened. The essential oil is evaporated by the in situ water in the plant materials. In this paper, it was observed that an improved SFME, in which a kind of microwave absorption solid medium, such as carbonyl iron powders (CIP), was added and mixed with the sample, can be applied to extraction of essential oil from the dried plant materials without any pretreatment. Because the microwave absorption capacity of CIP is much better than that of water, the extraction time while using the improved SFME is no more than 30 min using a microwave power of 85 W. Compared to the conventional SFME, the advantages of improved SFME were to speed up the extraction rate and need no pretreatment. Improved SFME has been compared with conventional SFME, microwave-assisted hydrodistillation (MAHD) and conventional hydrodistillation (HD) for the extraction of essential oil from dried Cuminum cyminum L. and Zanthoxylum bungeanum Maxim. By using GC-MS system the compositions of essential oil extracted by applying four kinds of extraction methods were identified. There was no obvious difference in the quality of essential oils obtained by the four kinds of extraction methods.     

Chemical Composition and Antimicrobial Activity of the Essential Oils Extracted by Microwave-Assisted Hydrodistillation from the Flowers of Two Plumeria Species

Microwave-assisted hydrodistillation (MAHD) was applied to obtain essential oils from the fresh flowers of Plumeria rubra Linn (PRL) and Plumeria rubra Linn var. acutifolia (PRLA) cultivated in China, which were subsequently analyzed via gas chromatography with flame ionization detection and gas chromatography with mass spectrometry. The essential oils were assessed for their antimicrobial activity. A variation of the chemical composition attributed to varieties was revealed. The essential oil of PRLA was found to have a high content of carboxylic acids (59.7%) with n-hexadecanoic acid (35.8%) and n-tetradecanoic acid (11.2%) as main components. Whereas, the PRL oil was characterized by high hydrocarbon content (38.6%), in which 9-hexacosene (14.6%) was found to be the major constituent. All essential oils possessed antimicrobial activity especially against five bacteria with diameter of inhibition zone (DD) and minimum inhibitory concentrations (MIC) values in the range of 6.8 to 21.3 mm and 2.8 to 46.5 mg/mL, respectively.     

Volatile Constituents of Achillea ligustica All. by HS-SPME/GC/GC-MS. Comparison with Essential Oils Obtained by Hydrodistillation from Corsica and Sardinia

The volatile components extracted from the headspace (HS) of Achillea ligustica All. samples and their separated organs using solid phase microextraction (SPME) were investigated by gas chromatography and gas chromatography-mass spectrometry. Fiftyseven compounds were identified, the main components were camphor (14.2–29.8%), artemisia ketone (0.3–26.7%), santolina alcohol (0.5–9.4%), camphene (3.0–9.0%) and trans-sabinyl acetate (1.6–5.5%). Moreover, the chemical composition of Corsican and Sardinian A. ligustica oils obtained from flowers and leafy stems harvested in four regions of both islands, were investigated. Two collective oils of A. ligustica were also investigated, comparison between both oils as well as from data literature were reported. A comparison of hydrodistillation and HS-SPME extraction of volatile components in term of isolation time, plant-consuming and chemical composition was discussed. HS-SPME technique was clearly fast in contrast to hydrodistillation (90 min/300 min). HS extraction was performed with a much smaller amount of plant than hydrodistillation. Although the aromatic profiles of HS-fractions and oils showed several quantitative differences HS-SPME can be applied to routine control analysis of aromatic and medicinal plants.

     

Antioxidant activity of crude extracts and essential oils from flower buds and leaves of Cistus creticus and Cistus salviifolius

Volatile oils from flowers and leaves of C. creticus L. and C. salviifolius L. were extracted by two extraction methods; namely, hydrodistillation and solid-phase micro-extraction (SPME). The chemical composition of essential oils was analyzed by GC and GC–MS. The volatile extracted from leaves and flowers of C. criticus using SPME was dominated by monoterpenes and sesquiterpenes hydrocarbon with α-pinene, camphene and α-cubebene as major components. In hydrodistillation, the oil extracted from leaves was dominated by oxygenated diterpenes and diterpenes hydrocarbon with manoyl oxide and sclarene as major components, whereas, the oil extracted from flowers was dominated by oxygenated diterpenes and diterpenes hydrocarbon with manoyl oxide and abietatriene as major components. The volatile from flowers and leaves of C. salviifolius obtained by SPME were dominated by monoterpenes and sesquiterpenes with δ-3-carene, α-pinene, β-pinene, and E-caryophyllene as major constituents. On the other hand, the oils from flowers and leaves of C. salviifolius obtained by hydrodistillation were dominated by oxygenated diterpenes, diterpenes hydrocarbon and esters with dehydro abietol, abietol, manoyl oxide and methyl octadecenoate as major components. In the leaves, the major components of the oil were manoyl oxide, E-ethyl cinnamate, and Z-ethyl cinnamate. These oils showed weak antioxidant activity when compared to the positive controls α-tocopherol, ascorbic acid, and EDTA, while the crude extracts aq. MeOH, butanol, and water showed good antioxidant activity. Discriminating between the studied plants based on the extraction method was also possible upon applying Principle component analysis (PCA) to the obtained GC–MS data.     

Comparison of continuous subcritical water extraction and hydrodistillation of marjoram essential oil.

Continuous subcritical water extraction (CSWE) and hydrodistillation were compared for the extraction of essential oil from marjoram leaves. Ground marjoram leaves (0.4 g) were subjected to dynamic extraction with water at 50 bar, 150 degrees C and 2 ml/min for 15 min. Hydrodistillation was performed treating 140 g of marjoram leaves with 1000 ml of water for 3 h. When CSWE was used the compounds were removed from the aqueous extract by a single extraction with 5 ml of hexane, detected by gas chromatography-flame ionization detection (GC-FID) and identified by mass spectrometry, electronic impact. The CSWE method is quicker (15 min versus 3 h), provides a more valuable essential oil (with higher amounts of oxygenated compounds and no significant presence of terpenes) and allows substantial savings of costs, in terms both of energy and plant material. The efficiency (in terms of volume of essential oil/1 g of plant) of CSWE is 5.1 times higher than that provided by hydrodistillation. The precision of the overall method (CSWE combined with GC-FID) is good (RSD less than 7.5%) for n = 5.     

Chemical composition,phytotoxic and antifungal properties of Ruta chalepensis L. essential oils

The chemical composition, and phytotoxic and antifungal activities of the essential oils isolated by using hydrodistillation from the aerial parts of Tunisian rue were evaluated. Significant variations were observed among harvest periods. The analysis of the chemical composition by gas chromatography/mass spectrometry showed that 2-undecanone (33.4–49.8%), 2-heptanol acetate (13.5–15.4%) and α-pinene (9.8–11.9%) were the main components. The antifungal ability of rue essential oils was tested by using disc agar diffusion against ten plant pathogenic fungi. A high antifungal activity was observed for the essential oil isolated at flowering developmental phase. Furthermore, rue essential oils showed high level of herbicidal activity against several weeds.     

Composition of the essential oil of Salvia officinalis L. from various European countries

Variations in the essential oil composition of Salvia officinalis L. growing in Estonia and in other European countries were determined. The oils were obtained in yields of 2.2-24.8 mL kg(-1). In three samples, the content of essential oil did not conform to the EP standard (10 mL kg(-1)). Variations in the essential oil composition of sage were studied using capillary gas chromatographic methods. A total of 40 components were identified. The principal components in the sage oils were 1,8-cineole, camphor, alpha-thujone, beta-thujone, borneol, and viridiflorol. The chemotypes of sage were not determined in investigated samples. The concentration of the main compounds in the drugs cultivated in Estonia varied in about the same range as the concentrations of these compounds in the oils of drugs obtained from other countries. The comparatively high concentration of toxic thujones seem to be characteristic to sage leaves cultivated in Estonia.     

Evaluation of volatile constituents of Cochlospermum angolense

The chemical composition of the essential oils obtained from the leaves and roots of Cochlospermum angolense (Welw) growing wild in Angola was analyzed for the first time by capillary gas chromatography (GC) and gas chromatography/mass spectrometry (GC-MS). The investigation led to the identification of 67 and 130 compounds from the leaves and roots, respectively. Both oils were strongly characterized by the presence of sesquiterpenoids (68.8% in the leaves and 53.2% in the roots), while monoterpenoids were present in minor percentages (9.8% in the leaves and 26.2% in the root). The main constituents of the leaves were germacrene D (9.4%), alpha-cadinol (7.4%) and 10-epi-cubenol (6.2%), while the most abundant compounds in the root essential oil were the sesquiterpenes beta-caryophyllene (19.7%) and isoborneol (6.6%). The analysis by HS-SPME of the roots, leaves, fruits and seeds were also reported for the first time. Different volatile profiles were detected.     

微波提取对挥发油化学成分的影响

采用无溶剂微波辅助提取与微波水蒸气蒸馏法提取薄荷叶和花椒挥发油,气相色谱-质谱(GC-MS)分析挥发油化学成分,与传统的水蒸气蒸馏对比,考察了微波对挥发油化学成分的影响.结果表明,微波促使薄荷叶挥发油中的薄荷醇氧化,转变为长叶薄荷酮和少量的薄荷呋喃酮.花椒挥发油中的按油素等化合物受质子的催化,在长时间温度较高的提取条件...     

广西产马尾松与湿地松针叶精油化学成分的比较

用水蒸气蒸馏法从广西产马尾松和湿地松的针叶中提取精油,探索了松针投料量和提取时间对产油率的影响,确定了最佳工艺条件为：松针投料量700 g,提取时间5 h。在此最佳条件下马尾松和湿地松针叶的产油率分别为0.45%和0.19%。用气相色谱（GC）和气相色谱-质谱（GC-MS）等方法分别对两树种的针叶精油进行了定量和定性分析,从马尾松针叶精油中分离出64种化学成分,鉴定了其中的20种成分,占挥发油总量的98.59%;从湿地松针叶精油中分离出73种化学成分,鉴定了其中的29种成分,占挥发油总量的94.23%。两树种针叶精油的主要化学成分大致相同,但在含量上有较大差别。马尾松针叶精油中α-蒎烯的含量约为湿地松的2.6倍,但其β-蒎烯含量低于后者。单萜和倍半萜是构成马尾松和湿地松针叶精油的主要成分。     

The chemical composition of the essential oils of Cirsium palustre and C. rivulare and their antiproliferative effect

The composition of the essential oils of Cirsium palustre and C. rivulare and their antiproliferative activity against breast adenocarcinoma cells (MCF-7 and MDA-MBA-231) were investigated. The essential oils obtained by hydro-distillation from the roots (yield 0.2 and 0.1% v/w, respectively), leaves and inflorescences (yield below 0.01%), were analyzed by gas chromatography coupled with mass spectrometry (GC-MS). The composition of the essential oils in the respective organs of each plant differed considerably. On the other hand, similarities were observed in the composition of root and leaf oils. In C. palustre and C. rivulare root oil, 50 and 39 constituents were identified, accounting for 95.3% and 92.4% of the total content. The main components were aplotaxene and its derivatives, representing 78.6% and 46.6% of the total content. In leaf oils of both species, 59 and 49 compounds, respectively, were identified, representing 67.4% and 78.3% of the total content. The major constituents were beta-damascenone (4.1% and 13.4%, respectively) and beta-ionone (6.7% and 5.3%, respectively). Short-chain saturated and unsaturated aliphatic alcohols and aldehydes constituted another important group of compounds (17.7% and 9.0%, respectively). The essential oils of the roots have moderate anti-proliferative activity, with IC50 values ranging from 110 to 140 microg/mL. These concentrations were below the level able to inhibit the proliferation of healthy cells.     

Microwave hydrodiffusion and gravity, a new technique for extraction of essential oils

A new process design and operation for the extraction of essential oils was developed. Microwave hydrodiffusion and gravity (MHG) is a combination of microwaves for hydrodiffusion of essential oils from the inside to the exterior of biological material and earth gravity to collect and separate. MHG is performed at atmospheric pressure without adding any solvent or water. MHG has been compared with a conventional technique, hydrodistillation (HD), for the extraction of essential oil from two aromatic herbs: spearmint (Mentha spicata L.) and pennyroyal (Mentha pulegium L.) belonging to the Labiatae family. The essential oils extracted by MHG for 15 min were quantitatively (yield) and qualitatively (aromatic profile) similar to those obtained by conventional hydrodistillation for 90 min. MHG also prevents pollution through potential 90% of energy saved which can lead to greenhouse gas emission benefits.