Hydrodistilled Essential Oil Research Articles

Chemical Composition and Antioxidant Activity of Essential Oil from Fresh and Dried Leaves of Echinops adenocaulos Boiss. from Jordan

Abstract: This study presents the first detailed analysis of hydrodistilled essential oils from fresh and air-dried Echinops adenocaulos Boiss. from the flora of Jordan. It aims to investigate the chemical composition and the antioxidant potency of the volatile compounds obtained by conventional hydrodistillation from the fresh and air-dried plant; gas chromatography-mass spectrometry analysis identified 46 and 75 compounds of the obtained essential oils, respectively. The study showed that the major constituent classes in the fresh aerial part are oxygenated diterpenes (76.92%) and oxygenated sesquiterpenes (10.78%), followed by aliphatic compounds (10.12%). However, in the dried aerial part, the main classes are oxygenated diterpene (74.47%) and aliphatic compounds (13.34%). Heyderiol was the most abundant constituent (44.96%), followed by bis(2-ethylhexyl)phthalate (20.12%) and trans-ferruginol (3.14%). Bis(2-ethylhexyl)phthalate (52.51%), followed by heyderiol (21.60%) and (Z)-ternine (8.81%) are the major compounds of the fresh aerial part. The antioxidant activity was tested by DPPH free radical scavenging and ABTS•+ cation radical scavenging. The oils from fresh and dried E. adenocaulos exhibit significant antioxidant activity, with the oil from the dried plant having higher antioxidant activity than that from the fresh one.

Essential Oil of Eucalyptus: A Natural Solution for Treating Pediculosis

Objective: Pediculosis is a condition caused by the infestation of Pediculus Humanus Capitis. The pesticides used in current formulations exhibit toxicity and carcinogenic effects on consumers. This study aimed to investigate the pediculicidal activity of the essential oil from Eucalyptus Globulus leaves, with the intention of adding it as an active ingredient in pediculicidal formulations to replace harmful chemicals.
 Design/methodology/approach: In vivo tests were conducted to assess the repellency and mortality of the essential oil obtained through hydrodistillation. The major components were determined through gas chromatography-mass spectrometry analysis. Additionally, proximate, and chemical composition analyses were performed on the eucalyptus leaves using ASTM E871, ASTM E872, ASTM D1104, TAPPI T264, TAPPI T207, ASTM D1106, and ASTM D1104 methods.
 Results: A repellency of 66.66% and 100% mortality within 2.26 minutes were obtained in the in vivo tests. The yield of hydrodistilled essential oil was 4 mL/kg, primarily composed of 71.04% 1,8-cineole, 18.94% 4-Ethyl-m-xylene, 2.72% γ-Terpinene, and 1.23% L-α-Pinene. Furthermore, the composition of eucalyptus leaves was determined as 61.25% moisture, 30.32% volatile matter, 6% ash, 2.40% fixed carbon, 11.22% acetone extractives, 33.03% water extractives, 31.49% lignin, 69.33% holocellulose, 62.09% cellulose, and 7.24% hemicellulose.
 Limitations on study/implications: The pediculicidal activity study was conducted solely on the essential oil, and further testing on the formulation of the finished product is necessary.
 Findings/conclusions: The pediculicidal activity study was conducted solely on the essential oil, and further testing on the formulation of the finished product is necessary.

Hydrodistillation of essential oil from peels of orange (Citrus sinensis) in the Mekong Delta, Vietnam: process optimization and chemical profiling

In this study, essential oils were extracted from peels of orange (Citrus sinensis) by employing hydrodistillation. The materials were collected in Ben Tre Province, Vietnam and the process was optimized by varying some experimental parameters including temperature, water-to-material ratio, extraction time and material size. The obtained essential oil was analyzed by Gas Chromatography-Mass Spectrometry to determine chemical composition. The maximal essential oil yield was determined as approximately 4%, obtained at the following conditions: ratio of water and lemon peels of 3:1 (mL/g), 60 mins and130°C. GC-MS results revealed that Limonene (98.454%), β-Myrcene (0.997%), and α-Pinene (0.549%) are the major constituents in the essential oil.

New insights into the chemical composition of Piper spp. collected in the northern region of Vietnam

Our study aimed to compare the essential oil composition of Piper species (Piperaceae) collected in the northern region of Vietnam and find possible fingerprints of different species. The aerial parts of seven Piper species including P. mutabile, P. leptostachyum, P. laosanum, P. boehmeriifolium, P. carnibracteum, P. albispicum, and P. longum were collected, shade-dried and chopped into small pieces before being submitted to the hydrodistillation of essential oils. The yields of essential oils ranged from 0.12 to 0.85%. GC-MS analysis of the essential oils led to the identification of 99 volatile components, accounting for 92.5–99.6% of the total oils. Sesquiterpenes (40.3–93.0%) were commanding in all essential oils while monoterpenes were only dominant in essential oils from P. albispicum (29.8%) and P. longum (29.4%). The distances between groups of seven Piper essential oils were measured using multivariate analysis. Elemene isomer seems to be the characteristic compound of all seven Piper essential oils. Besides, the essential oil from P. mutabile in the present study was characterized by the very high content of safrole (20.9%) while epi-γ-eudesmol (15.9%), cis-caryophyllene (14.4%), trans-caryophyllene (10.6%), guaiol acetate (10.1%), eremophilene (9.6%) were main components in essential oil from P. laosanum. Essential oil of P. boehmeriifolium was dominated by elemene isomer (15.6%), eremophilene (14.2%), and trans-caryophyllene (9.3%). Essential oil from P. albispicum in our study featured by high contents of eremophilene (11.1%) and β-pinene (10.1%). In the other hand, essential oil from P. carnibracteum was characterized by the dominant amount of trans-caryophyllene (21.7%), α-muurolene (21.1%), bicyclo[4.3.0]nonane,7-methylene-2,4,4-trimethyl-2-vinyl- (17.8%) while aromadendrene (25.7%), γ-cadinene (20.3%) were ascendant in essential oil from P. leptostachyum. To the best of our knowledge, this is the first time that the essential oil composition of P. leptostachyum and P. carnibracteum were investigated. Besides, the volatile components in the essential oils from P. albispicum, P. laosanum, and P. mutabile showed some differences in the comparison to the data published previously on the chemical composition of these aforesaid species which could depend on many factors.

GC/MS analysis of the hydrodistilled essential oils and volatiles from the aerial parts of Cannabis sativa L

Cannabis sativa L. has been recognised as a narcotic drug in different parts of the world. The current report deals with the screening of the chemical profiles of the essential oils (EOs) and volatiles obtained from the aerial ports of Cannabis sativa L. (APCS) using classical hydrodistillation (HD), solid phase microextraction (SPME) along with a new technique namely innovative cigarette ignition (Incigig); all in combination with GC/MS. The characterised profiles had considerable differences from quantitative and qualitative points of view, with a high prevalence of non-terpene hydrocarbons for the EO and oxygenated monoterpenes for both volatiles using SPME and Incigig approaches.

Unveiling the Impact of Drying Methods on Phytochemical Composition and Antioxidant Activity of Anthemis palestina.

Different drying techniques may alter the chemical composition of plant extracts and consequently affect their bioactivity potential. The current study was designed to reveal the effect of four different drying methods on the phytochemical composition and antioxidant activity of hydrodistilled essential oil (HD-EO) and methanolic (APM) extract obtained from the aerial part of Anthemis palestina from Jordan. Aerial parts of A. palestina in their fresh (FR) form and after drying in shade (ShD), sun (SD), oven at 40 °C (O40D) and 60 °C (O60D), in addition to microwave (MWD), were used to extract their essential oils by hydrodistillation and to prepare the different methanolic extracts (APM). GC/MS analysis of the different HD-EOs revealed qualitative and quantitative differences among the different samples. While FR, O40D, O60D, and MWD EO samples contained mainly sesquiterpene hydrocarbons (35.43%, 29.04%, 53.69%, and 59.38%, respectively), ShD sample was rich in oxygenated monoterpenes (33.57%), and SD-EO contained mainly oxygenated sesquiterpenes (40.36%). Principal component analysis (PCA) and Cluster analysis (CA) grouped the different drying methods based on their impact on the concentration of chemical constituents. SD-EO demonstrated high DPPH and ABTS antioxidant activity (1.31 ± 0.03) × 10-2; (1.66 ± 0.06) × 10-2 μg/mL, respectively). Furthermore, A. paleistina methanolic extracts (APM) obtained after subjecting the plant to different drying methods showed interesting patterns in terms of their TPC, TFC, antioxidant activity, and phytochemical profiling. Of all extracts, SD-APM extract had the highest TPC (105.37 ± 0.19 mg GA/g DE), highest TFC (305.16 ± 3.93 mg Q/g DE) and demonstrated the highest DPPH and ABTS scavenging activities ((4.42 ± 0.02) × 10-2; (3.87 ± 0.02) × 10-2 mg/mL, respectively); all were supported by correlation studies. LC-MS/MS analysis of the different extracts revealed the richness of the SD-APM extract in phenolic acids and flavonoids.

Physicochemical characterization, antioxidant and antifungal activities of essential oils of Urginea maritima and Allium sativum

Abstract This study aims to contribute to the valorizing of aromatic and medicinal plants of Morocco by studying the antioxidant and antifungal properties of the essential oils (EOs) of Allium sativum (AS) (garlic) and Urginea maritima (Syn. Drimia maritima) tested in vitro. After the hydrodistillation of EOs, we determined their physicochemical indices according to an international standard (Moroccan ISO standard), and the chemical composition of the oils was studied by gas chromatography coupled with mass spectrometry (GC-MS). Then, the antioxidant properties were determined using the free radical scavenging capacity of 2,2-diphenyl-1-picrylhydrazyl and the ferric-reducing antioxidant power of these oils. The evaluation of the antifungal activity was carried out by the direct contact method against two fungal strains, Fusarium oxysporum and Fusarium equiseti. GC-MS analysis revealed a significant percentage of terpenes in U. maritima EO, with terpinolene (21.82%) and estragole (6.24%) as the main compounds. Biological tests have demonstrated the remarkable antioxidant activities of this EO compared with AS EO, with an IC50 of 1.03 mg/mL and an RP0.5 of 1.60 mg/mL. On the other hand, while A. sativum (garlic) EO showed exceptional antifungal activities, with 100% inhibition and MICs of 0.5 µL/mL for F. equiseti and 2.5 µL/mL for F. oxysporum. Also, regardless of its antioxidant properties being moderate, this EO stands out for its efficacy against fungal infections of the Fusarium genus. In summary, the results suggest that U. maritima EO could be used as a natural source of antioxidants, while garlic EO could be considered a potentially effective treatment against fungal infections caused by Fusarium fungi.

Antiproliferative evaluation of the hydro-distilled oil of celery, coriander, dill, and fennel and chemometric analysis of their aroma profile

Main pharmacological activities observed with the aromatic herbs celery, coriander, dill, and fennel have been attributed primarily to their essential oils, obtained by hydro-distillation. Still, there is a lack in research on the flavor of these selected four aromatic plants with multiple biological activities. The current study sought to identify and quantify the chemical composition of the spontaneous emitted volatile organic compounds (VOCs) of their fresh leaves, and to statistically analyze their composition using principal component analysis (PCA) and hierarchial cluster analysis (HCA). In vitro cytotoxic activities of their hydro-distilled essential oils were evaluated against MCF-7 and HCT-116 cell lines using MTT assay. The emitted VOCs, captured by solid phase micro extraction (SPME) method were analyzed by GC/GC-MS. The main terpenoid components of the aroma profile of celery and coriander were limonene, that of dill α-phellandrene, and of fennel α-terpinene. The systematic analysis using both, HCA and PCA of the spontaneous emitted VOCs of the fresh leaves of the four Apiaceae members growing in Jordan, revealed a clear picture of the distinct odor of these edible aromatic plants. The hydro-distilled essential oil of fennel exhibited the best antiproliferative activity against MCF-7 and HCT-116 cell lines with respective IC50’s of 0.35, and 0.42 mg/mL. The composition of the VOCs of the leaves of celery, coriander, dill, and fennel, growing in Jordan was determined for the first time, in addition to their antiproliferative activities.

Comparative study of hydro- and steam-water distillation for isolation of essential oils from needles of Cupressus torulosa D. Don

Cupressus torulosa, a large aromatic evergreen conifer tree widely distributed in the northwestern Himalayan region of India, holds various traditional uses of its aerial parts. The objective of this study was to compare the essential oil content and chemical composition of C. torulosa needles obtained using two distinct distillation methods: hydro-distillation (HD) and steam-water distillation (SWD). Gas Chromatography with Flame Ionization Detector (GC-FID) and Gas Chromatography-Mass Spectrometry (GC-MS) techniques were employed to determine the compositions of the oils. The results indicated that the hydro-distilled essential oil (HDEO) exhibited significantly higher content (0.73±0.09%) compared to the steam-water distilled essential oil (SWDEO, 0.19±0.02%). Additionally, the HDEO and SWDEO exhibited notable differences in their chemical composition. The HDEO was primarily rich in oxygenated monoterpenes (58.45%), with terpinen-4-ol (29.09%) and umbellulone (21.29%) identified as the major constituents. On the other hand, the SWDEO was dominated by monoterpene hydrocarbons (73.75%), with α-pinene (22.19%), δ-3-carene (19.98%), and limonene (14.7%) as the main components. The findings from this study can assist in selecting the appropriate distillation technique to obtain essential oils with desired chemical compositions for various end-use applications.

Variations in the composition and biochemical attributes of Eucalyptus camaldulensis L. leaves essential oil as function of drying methods

The current study focuses on the chemical composition and biological properties of the hydro-distilled essential oil from Eucalyptus camaldulensis leaves, including its antibacterial, antioxidant, and anti-inflammatory properties. Three distinct drying techniques (sun drying, shade drying, and oven drying) were used to dry the plant leaves. The yield of essential oils from E. camaldulensis leaves (ELEOs) ranged from 1.0% (shade-dried sample) to 2.25% (sun-dried sample). The strongest antibacterial activity against Bacillus subtilis was seen in the essential oil from shade-dried leaves, which also had notable antioxidant and anti-inflammatory potential. The shade-dried variant, which was followed by the sun-dried and oven-dried variants, had the highest total phenolic contents (TPC), total flavonoid contents (TFC), and DPPH scavenging potential. These values were 54.07, 38.95, 16.86 (GAE mg/100g for TPC), 66.43, 29.09, 3.76 (CE mg/100g for TFC), and 66.58, 54.56, 24. 25 (IC50 μg/mL for DPPH scavenging). The shade-dried ELEOs, among others, with paw diameters of 0.739, 1.133, and 1.143 mm at 0, 30, and 60 min, respectively, showed the strongest inhibition of anti-inflammatory activity. According to GC-MS analysis, 1,8-cineole (28.08-42.70%), terpinol (11.19-19.28%), terpen-4-ol (9.74-12.33%), and β-pinene (7.89-9.51%) were the prominent components found in the evaluated ELEOs, followed by p-cymene (4.96-5.92%). The volatile profile and biological activity of ELEOs show wide variations in this study depending on the drying technique. Overall, these findings encourage peel samples to be dried at room temperature in order to gain maximal nutritional and nutraceutical benefits of this under-utilized agro-waste.

Microwave Assisted Hydrodistillation Essential Oil from Lime Peel Waste as Aromatherapy Candles

Flavonoids belong to the extensive group of polyphenol compounds. They can function as antioxidants and antibacterials by denaturing bacterial cell proteins and damaging bacterial cells. One source of essential oils is lime peel, which is often discarded and goes unused. The distillation method utilizes microwaves, offering an alternative to conventional distillation techniques and resulting in enhanced effectiveness and efficiency. The Microwave Assisted Hydrodistillation (MAHD) method proves to be more energy-efficient, environmentally friendly, rapid, safe, and cost-effective. This study aims to assess the impact of the MAHD method on the quantity and quality of essential oils extracted from lime peels. Laboratory tests are conducted in accordance with Indonesian national standards. The overarching objective is to establish a process that transforms discarded lime peels into aromatherapy candles, contributing to respiratory health. The MAHD method is employed with a sample mass to distilled water solvent ratio of 1:1. The resulting essential oil undergoes analysis using the GC-MS method. According to the GC-MS test results, the compound with the highest percentage area is limonene at 98%. This is followed by trans-caryophyllene at 99% with a retention time of 12.422, and beta-selinene at 99% with a retention time of 13.191.

EFFECT OF ESSENTIAL OIL FROM Feroniella lucida (SCHEFF.) SWINGLE FRUIT ON Staphylococcus aureus

Staphylococcus aureus is a bacterium commonly found on human skin and mucus membrane linked to the severity of the chronic inflammatory skin disease, and a contaminant in food. This study presented the effect of essential oil extracted from Feroniella lucida (Scheff.) Swingle fruit for its antibacterial activity against two strains of Staphylococcus aureus, ATCC 29213 and TISTR 517; and its chemical composition. The hydro-distillated essential oil yield from the peel was approximately 0.72% (v/w, fresh weight), compared to the average yield of 0.10% (v/w) from the plant leaves. The major components of the peel oil were decyl acetate (56.20% of the total GC-MC peak area), decanal (22.49%), and dodecyl acetate (6.81%). The oil could inhibit both strains, but the ATCC 29213 was more sensitive than TISTR 517 with the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of 0.125 and 2.0, and 0.5 and 16.0 mg/mL, respectively. For the mode of action performed for the strain ATCC 29213, the essential oil had a significant effect to inhibit the bacterium growth within 2 h, and caused protein, potassium ion, and adenosine triphosphates (ATP) leakages, but it had no effect on the leakage of nucleic acids. Under scanning electron microscope (SEM) observation of the essential oil effect on the bacterial cell morphology, the crease and furrow of ATCC 29213 cells were detected. These results encourage further application of the oil from the edible fruit as anti-Staphylococcus aureus to develop skin care products as well as to be used in food industry.

Ploidy affects phytochemistry and micromorphology of Thymus persicus (Ronniger ex Rech.f.) Jalas: An in vitro investigation

Thymus persicus (Ronniger ex Rech. f.) Jalas (Lamiaceae) is an endemic and valuable essential oil-bearing plant. Herein, the effect of ploidy level on both anatomical structure and essential oil composition was investigated. Leaves of in vitro-induced tetraploids had more glandular peltate, capitate, and elongated non-glandular trichomes compared to diploids. Gas chromatography-flame ionization detector (GC-FID), and GC–mass Spectrometry (GC-MS) techniques were employed to unravel chemicals in hydro-distilled essential oils from in vitro diploid, tetraploid, and mixoploid clones. Notably, 21, 27 and 17 compounds representing 97.0%, 96.9%, and 96.7% of the total essential oils were identified and quantified in diploids, tetraploids, and mixoploids plants, respectively. A wide chemical variability was observed so much so that thymol (32.8%), α-terpineol (26.4%), and carvacrol (6.2%) were the main constituent in diploids, while carvacrol (33.85%), δ-selinene (8.79%), ishwarone (8.23%), and octanoic acid (8.07%) were in tetraploids and mixoploids mostly accounted in δ-Selinene (21.26%), pogostol (13.92%), methyl thujate (10.94%), and (2E,6E)-farnesyl acetate (10.28%). To further underline the ploidy effects, it was observed a strong decrease in the contents of monoterpene hydrocarbons and oxygenated monoterpene hydrocarbons in tetraploids and myxoploids. The sesquiterpene hydrocarbons showed an inverse behaviour.

Environmental stress tolerance, hydro-distilled essential oils characteristics and biological activities of Eucalyptus torquata Luehm.

Eucalyptus has become one of the most widely planted genera in the world because of its tolerance to a wide range of soil types and climates, as well as for its many industrial, commercial and medicinal uses. Eucalyptus torquata Luehm. is a plantation species frequently planted in semi-arid and arid regions for its ecological, forestry, ornamental and melliferous interests. Based on literature, drought tolerance of this species was mostly directed to adaptation mechanisms. Physiological investigations reveal the importance of stomatal closure and increased solute contents suggesting that osmotic adjustment is one of the main responses to drought in E. torquata. On the other hand, it showed low sensitivity to salt stress. This paper also highlights the immense benefits of E. torquata which contains essential oils with variable chemical composition and rich essentially in 1,8-cineole, torquatone, α-pinene, trans-myrtanol, α-eudesmol, β-eudesmol, globulol, trans-pinocarveol and aromadendrene. These oils, as well as the methanol and aqueous extracts possess a wide variety of bioactivities of great importance which are particularly valuable as antibacterial and antifungal agents also have a strong toxicity against insects and mites in addition to antiproliferative and cytotoxic effects against different types of cancer cells.

Exploring Echinops polyceras Boiss. from Jordan: Essential Oil Composition, COX, Protein Denaturation Inhibitory Power and Antimicrobial Activity of the Alcoholic Extract.

In this article, we present the first detailed analysis of the hydro-distilled essential oil (HDEO) of the inflorescence heads of Echinops polyceras Boiss. (Asteraceae) from the flora of Jordan, offering observations at different growth (pre-flowering, full-flowering and post-flowering) stages. Additionally, we investigated the methanolic extract obtained from the aerial parts of the plant material at the full flowering stage in order to determine its inhibitory activity in terms of COX and protein denaturation and evaluate its antimicrobial effects against S. aureus (Gram-positive) and E. coli (Gram-negative) bacteria. Performing GC/MS analysis of HDEO, obtained from the fresh inflorescence heads at the different growth stages, resulted in the identification of 192 constituents. The main class of compounds detected in these three stages comprised aliphatic hydrocarbons and their derivatives, which amounted to 50.04% (pre-flower), 40.28% (full-flower) and 41.34% (post-flower) of the total composition. The oils also contained appreciable amounts of oxygenated terpenoids, primarily sesquiterpenoids and diterpenoids. The pre-flowering stage was dominated by (2E)-hexenal (8.03%) in addition to the oxygenated diterpene (6E,10E)-pseudo phytol (7.54%). The full-flowering stage primarily contained (6E,10E)-pseudo phytol (7.84%), β-bisabolene (7.53%, SH) and the diterpene hydrocarbon dolabradiene (5.50%). The major constituents detected in the HDEO obtained at the post-flowering stage included the oxygenated sesquiterpenoid intermedeol (5.53%), the sesquiterpene hydrocarbon (E)-caryophyllene (5.01%) and (6E,10E)-pseudo phytol (4.47%). The methanolic extract obtained from air-dried aerial parts of E. polyceras displayed more COX-2 inhibition than COX-1 inhibition at a concentration level of 200 µg/mL. The extract exhibited a capacity to inhibit protein denaturation that was comparable with respect to the activity of diclofenac sodium and displayed moderate levels of antimicrobial activity against both bacterial species. The current results demonstrate the need to perform further detailed phytochemical investigations to isolate and characterize active constituents.

Comparative GC-MS Analysis of Fresh and Dried Curcuma Essential Oils with Insights into Their Antioxidant and Enzyme Inhibitory Activities.

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.

Chemical constituents and biological activities of the seed essential oil from Michelia tonkinensis grown in Thanh Hoa province, Viet Nam

AbstractEssential oils (EOs) from the seed of Michelia tonkinensis were extracted in four ways hydrodistillation (HD), microwave‐assisted hydrodistillation (MHD), ultrasound‐assisted hydrodistillation (UHD) and enzyme‐assisted hydrodistillation (EHD). The chemical constituents of these EOs were analysed by gas chromatography (GC‐FID) and gas chromatography/mass spectrometry (GC/MS). Phenylpropanoids were the main components in which safrole is the dominant constituent (82.98‐91.53%), followed by monoterpene hydrocarbons (5.26‐11.94%). In comparison with traditional hydrodistillation method (HD only), the EOs obtained from the MHD, UHD and EHD methods have the higher safrole contents (91.32%, 90.96% and 90.25%, respectively). The essential oils were also tested for their antioxidant, anti‐imflammatory, antimicrobial and cytotoxic activities. The HD essential oil sample showed inhibitory activity against 6/8 tested microorganisms, i.e., Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Bacillus subtillis, Candida albicans, and Saccharomyces cerevisiae. The MHD and EHD exhibited the inhibitory activity against three strains E. coli, A. niger and F. oxysporum. The UHD inhibited E. coli and F. oxysporum.

Antimicrobial and Radical Scavenging Activitıes of Essential Oils from Kaempferia larsenii Sirirugsa

Introduction: K. larsenii (Zingiberaceae) is an endemic and rare species in Thailand. There have been no previous reports on chemical compositions and biological properties of essential oils from the fresh root and rhizome. This research aims to investigate the chemical compositions, antimicrobial and radical scavenging activities of essential oils from the fresh root and rhizome of K. larsenii. Materials and methods: The chemical compositions of hydrodistilled essential oils were analysed by GC-MS technique. The antimicrobial activity was tested by the disc diffusion assay. The Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values were also evaluated. The radical scavenging activities were evaluated using ABTS, DPPH and hydroxyl radical scavenging activity assay. Results and discussion: Camphene was considered as the main component in root and rhizome essential oils (36.35 and 48.00 %, respectively). The essential oils showed strong antimicrobial activity against S. aureus. The rhizome essential oil showed strong DPPH and hydroxyl radical scavenging activities while the root essential oil exhibited strong hydroxyl radical scavenging capacity. Conclusions: The essential oils exhibit strong antimicrobial especially Gram-positive bacteria and antioxidant activity. Therefore, it might be used as a potential source of natural antidiarrheal and antioxidant substances for food and cosmeceutical product industries. HIGHLIGHTS The essential oils were obtained from hydrodistillation of the fresh root and rhizome of K. larsenii Camphene was the major component in both root and rhizome essential oils The root and rhizome essential oils showed strong antimicrobial on Gram-positive bacteria and radical scavenging activities This is the first report on the biological activities of the fresh root and rhizome essential oils of larsenii GRAPHICAL ABSTRACT

Phytochemical and bioactivity evaluation of secondary metabolites and essential oils of Sedum rubens growing wild in Jordan

Sedum rubens L. (Crassulaceae family) is an interesting succulent medicinal plant that has never been investigated for its phytochemical constituents. Thus, the current study was designed to unveil its chemical constituents and bioactivity potentials. In the current study, the total phenol content (TPC), total flavonoid content (TFC) and DPPH radical scavenging properties of the hydroalcoholic (HA) and water extracts (W) were determined. Moreover, the presence of selected phenolic acids (gallic acid, chlorogenic acid, caffeic acid) and flavonoids (rutin, quercetin, hesperidin) was determined by HPLC-PDA. In addition, hydro-distilled essential oil (HDEO) composition of the plant at the pre-flowering (PF) and full-flowering (FF) stages was determined by GC/MS and GC/FID techniques. Results revealed that the FF hydroalcoholic extract had the highest TPC (136.9 mg gallic acid/g extract), TFC (234.7 mg quercetin/g extract) and DPPH• radical scavenging activity (7.10 × 10-2 ± 1.0 × 10-3 mg/mL). This extract was rich in gallic acid and caffeic acids (366, 243 mg/Kg dry plant, respectively). The study resulted in reporting four known compounds including α- & β-amyrin acetates, β-sitosterol and β-sitosterol glycoside for the first time from the plant. The HDEO at the PF and FF stages were dominated by oxygenated sesquiterpenes (21.92%) and aliphatic hydrocarbons (45.71%).

GC-MS Analysis of the Essential Oil from Seseli mairei H. Wolff (Apiaceae) Roots and Their Nematicidal Activity.

The essential oil (EO) was extracted from aerial parts with insecticidal and fungicidal activity. Herein, the hydro-distilled essential oils of Seseli mairei H. Wolff roots were determined by GC-MS. A total of 37 components were identified, (E)-beta-caryophyllene (10.49%), β-geranylgeranyl (6.64%), (E)-2-decenal (6.17%) and germacrene-D (4.28%). The essential oil of Seseli mairei H. Wolff had nematicidal toxicity against Bursaphelenchus xylophilus with a LC50 value of 53.45 μg/mL. The subsequent bioassay-guided investigation led to the isolation of three active constituents: falcarinol, (E)-2-decenal, and octanoic acid. The falcarinol demonstrated the strongest toxicity against B. Xylophilus (LC50 = 8.52 μg/mL). The octanoic acid and (E)-2-decenal also exhibited moderate toxicity against B. xylophilus (LC50 = 65.56 and 176.34 μg/mL, respectively). The LC50 of falcarinol for the toxicity of B. xylophilus was 7.7 and 21 times than that of octanoic acid and (E)-2-decenal, respectively. Our findings demonstrate that the essential oil from Seseli mairei H. Wolff roots and their isolates may be developed as a promising natural nematicide.