Influence of the process, season, and origin on volatile composition and antioxidant activity of Juniperus phoenicea L. leaves essential oils

Essential oils of Juniperus phoenicea L. leaves cultivated in 3 regions, Korbos, Matmata, and Tabarka of Tunisia were obtained by hydrodistillation (HD), steam distillation (SD), and Soxhlet (SH) extraction methods. The essential oils were analyzed and quantified by capillary gas chromatography using flame ionization detection (GC-FID) and mass spectrometry (GC-MS). The highest yield was observed in HD process (1.12%). Tabarka essential oil provided the best yield 0.79% compared to other regions. December month SD essential oil was the highest in oxygenated monoterpenes (52.7%). Nevertheless, SH essential oil showed a higher content in sesquitepenes hydrocarbons (64.5%). α-Terpinol (25.5%) was the main oxygenated component in Matmata juniper essential oil, extracted by SD. Moreover, the antioxidant activity of essential oils was evaluated using ABTS assays. The strongest antioxidant activity (IC(50) = 22.6 ± 0.7 mg/L) was obtained by the Matmata (October 2007) SD essential oil.     

Chemical composition and antioxidant and antimicrobial activities of essential oil of Allium sphaerocephalon L. subsp. sphaerocephalon (Liliaceae) inflorescences

BACKGROUND: Allium sphaerocephalon is a wild‐growing plant commonly used as an onion substitute. In this study the essential oil obtained from A. sphaerocephalon subsp. sphaerocephalon inflorescences was analysed by gas chromatography and gas chromatography/mass spectrometry and also evaluated for in vitro antioxidant and antimicrobial activities. The obtained results are reported for the first time and discussed with respect to the sulfur compounds detected in the essential oil. RESULTS: Ninty‐one compounds were identified, representing 91.6% (w/w) of the total oil. Major constituents of the analysed sample were shyobunol (15.3%), β‐caryophyllene (8.1%), α‐cadinol (7.8%), 3,5‐diethyl‐1,2,4‐trithiolane (isomer II, 5.9%) and δ‐cadinene (5.2%). The diluted oil had an antioxidant capacity of 160 000 ± 111 µmol α‐tocopherol acetate equivalents g^?1. Its antimicrobial activity was evaluated against five bacterial and two fungal strains using the broth microdilution assay. Among the micro‐organisms tested, the most susceptible strains were Pseudomonas aeruginosa (minimal inhibitory/bactericidal concentration = 0.08/2.5 mg mL^?1) and Aspergillus niger (minimal inhibitory/fungicidal concentration = 0.31/0.63 mg mL^?1). CONCLUSION: The results showed that the examined species had strong antioxidant and antimicrobial properties and are in accordance with the popular use of plants belonging to the genus Allium in traditional medicine, emphasising the necessity of further detailed study of the active principles in Allium species. Copyright © 2010 Society of Chemical Industry     

Evaluation of fruit extracts of six Turkish Juniperus species for their antioxidant, anticholinesterase and antimicrobial activities

BACKGROUND: Juniperus L. (Cupressaceae) species are mostly spread out in the Northern Hemisphere of the world, and some of them are used as folkloric medicines. The fruits of some species are eaten. Since oxidative stress is one of the reasons for neurodegeneration and is associated with the Alzheimer's disease (AD), the extracts prepared from the fruits of six Juniperus species were screened for their antioxidant activity. Therefore, the extracts were also evaluated against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), which are chief enzymes in the pathogenesis of AD. In addition, antimicrobial activity was also evaluated. RESULTS: In the β‐carotene–linoleic acid assay, acetone extracts of J. oxycedrus subsp. oxycedrus, J. sabina and J. excelsa, and methanol extracts of J. phoenicea and J. sabina, effectively inhibited oxidation of linoleic acid. The hexane extracts of J. oxycedrus subsp. oxycedrus, J. foetidissima and J. phoenicea showed remarkable inhibitory effect against AChE and BChE. CONCLUSION: Because of their high antioxidant activity, J. excelsa, J. oxycedrus subsp. oxycedrus, J. sabina and J. phoenicia might be used in the food industry as preservative agents or extension of the shelf‐life of raw and processed foods. Since the hexane extracts of J. oxycedrus subsp. oxycedrus and J. foetidissima demonstrated significant anticholinesterase activity they should be considered as a potential source for anticholinesterase agents. Copyright © 2010 Society of Chemical Industry     

GC/MS analysis and antimicrobial and antioxidant activities of essential oil of Eucalyptus radiata

BACKGROUND: The essential oil from Eucalyptus radiata leaves collected in Tunisia was extracted by steam distillation and analysed by gas chromatography/flame ionisation detection and gas chromatography/mass spectrometry. Its antioxidant and antiradical properties were evaluated by the 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) and 2,2′‐azinobis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS) assays. The antimicrobial activity of the oil was examined in vitro against two plant‐pathogenic bacteria (four strains each of Agrobacterium tumefaciens and Pseudomonas savastanoi pv. savastanoi) and two plant‐pathogenic fungi (Fusarium solani and Rhizoctonia solani). RESULTS: Thirty‐five compounds were identified and quantified in the essential oil, the major ones being 1,8‐cineole (69.53%), α‐pinene (11.94%) and trans‐pinocarveol (4.81%). Medium antioxidant activity was found in the ABTS assay (IC₅₀ = 484.3 ± 17.3 mg L^?1), whereas no significant free radical‐scavenging activity was detected in the DPPH assay (IC₅₀ > 10 000 mg L^?1). The antimicrobial assays showed that the oil exhibited a high level of activity against A. tumefaciens and R. solani, with minimum inhibitory concentrations ranging between 750 and 1000 µL L^?1. However, it was less efficient against P. savastanoi pv. savastanoi and F. solani. CONCLUSION: The results indicate that the essential oil of E. radiata, with a high content of terpenic compounds, exhibits significant antimicrobial activity against strains of A. tumefaciens and the fungus R. solani and may therefore be useful for their control. Copyright © 2009 Society of Chemical Industry     

蒌叶挥发油的提取及抗氧化和抑菌活性研究

采用水蒸气提取法对蒌叶挥发油进行提取,在单因素实验的基础上,以正交实验筛选最佳的提取工艺条件;同时考察蒌叶挥发油抗氧化和抑菌活性。结果表明,蒌叶挥发油提取的最佳工艺条件为:料液比m_干蒌叶粉∶V_水=50∶1000（g/m L）,超声时间为30 min,超声温度70℃,超声功率192 W,加热回流提取4 h,蒌叶挥发油的得率为2.96%。蒌叶挥发油清除DPPH·和·OH的IC₅₀分别为33.19、71.11μg/m L;挥发油对金黄色葡萄球菌、枯草杆菌、大肠杆菌、蜡状芽孢杆菌、四联球菌、藤黄八叠球菌、白色葡萄球菌、黑曲霉、毛霉、青霉均有明显的抗菌活性,其MIC分别为0.625、1.25、0.625、0.625、0.625、2.50、1.25、0.313、0.625、0.313 mg/m L,故蒌叶挥发油具有较强的抗氧化和抑菌活性。      

Comparative chemical composition,antioxidant and hypoglycaemic activities of Juniperus oxycedrus ssp. oxycedrus L. berry and wood oils from Lebanon

Juniper (Juniperus oxycedrus) is used in European cuisine for its distinguishing flavour. J. oxycedrus ssp. oxycedrus berry and wood essential oils were tentatively identified by GC and GC/MS. Fifty compounds were identified in the berry oil and 23 compounds were identified in the wood oil. The J. oxycedrus ssp. oxycedrus berry oil was characterised by high contents of α-pinene (27.4%) and β-myrcene (18.9%). Other important compounds were α-phellandrene (7.1%), limonene (6.7%), epi-bicyclosesquiphellandrene (2.3%) and δ-cadinene (2.2%) while, in the wood oil, δ-cadinene (14.5%) is a major main component, together with cis-thujopsene (9.2%) and α-muurolene (4.9%). In vitro evaluation of antioxidant activity by the DPPH method showed a significant activity for both oils with IC₅₀ values of 1.45 μl/ml for wood and 7.42 μl/ml for berries. Hypoglycaemic activity was investigated through the inhibition of α-amylase. The results revealed that oil obtained by hydrodistillation from J. oxycedrus ssp. oxycedrus wood exhibits an interesting activity with IC₅₀ of 3.49 μl/ml.     

Chemical Composition and Antimicrobial and Antioxidant Activities of Essential Oils and Various Extracts of Juniperus phoenicea L. (Cupressacees)

ABSTRACT:  GC-FID and GC-MS analysis of essential oils of  Juniperus phoenicea  resulted in the identification of 30 compounds, representing more than 98% of the total composition. α-pinene (55.7% and 80.7%), δ-3-carene (10.7% and 4.5%), and γ-cadinene (2.9% and 5.1%) were the main components, respectively, in leaves and berries essential oil. Extracts of  J. phoenicea  were obtained by different extraction solvents: methanol, ethanol, ethyl acetate, and dichloromethane and evaluated composition for polyphenols (gallic acid equivalent 52 to 217 g/kg), tannins (catechin equivalent 6.5 to 60.2 g/kg), antocyanins (cyanidin equivalent 84 to 373 mg/kg), and flavonoids (quercetin equivalent 6.4 to 29.3 g/kg). The samples (essential oils and extracts) were subjected to a screening for their antioxidant activity by using DPPH and ABTS assays; antimicrobial activity was tested with 6 bacteria (3 Gram-positive and 3 Gram-negative), 1 yeast, and 2 fungi. The strongest antioxidant activity was obtained by the methanolic extract ( IC ₅₀= 6.5 ± 0.3 mg/L). Flavonoids are likely to contribute to the antifungal activity against  Saccharomyces cerevisiae.  Correlations were studied between chemical composition and antioxidant and antimicrobial activities.     

甜橙精油的化学成分、抑菌和抗氧化活性研究

采用气相色谱-质谱法（GC-MS）对甜橙精油的挥发性成分进行分析,通过抑菌圈实验和试管二倍稀释法对其抑菌效果、最低抑菌浓度（MIC值）进行测定,采用3种方法（DPPH、ABTS和FRAP）对甜橙精油的抗氧化活性进行体外评价。结果表明:甜橙精油含有101种组分,鉴定出50种成分,主要为脂肪族（5.96%）和萜类化合物（78.39%）;甜橙精油对6种供试菌均有较明显的抑制作用,其中对枯草芽孢杆菌的抑制作用最强（MIC值7.5μL/m L）,绿色木霉最弱（MIC值15μL/m L）;甜橙精油对DPPH自由基和ABTS+自由基有明显的清除作用,样品量与清除率间呈量效关系。      

蓬莪术干叶和鲜叶精油化学成分分析与抗氧化、抑菌活性研究

通过GC/MS技术分析了蓬莪术叶片精油的化学组成,确定了各成分在精油中的相对含量,并采用清除DPPH自由基、清除ABTS自由基、抑制亚油酸脂质过氧化和抑制卵黄脂质过氧化能力,测定了精油的抗氧化能力,以滤纸片琼脂扩散法测定抗菌活性。结果表明:蓬莪术干叶中鉴定出31种成分,鲜叶中鉴定出36种成分,分别占总峰面积的83.05%和82.29%,主要由单萜烯类和倍半萜类组成,并含有微量的醇类、醛类、酮类和烷类等物质。蓬莪术叶精油对金黄色葡萄球菌、大肠杆菌、枯草芽孢杆菌和沙门氏菌均有抑制作用,且随浓度的增加抑制作用增强。      

Chemical composition and antimicrobial activity of the essential oil of Amomum tsao‐ko

BACKGROUND: The chemical composition of the essential oil obtained by hydrodistillation from the dried fruits of Amomum tsao‐ko was analysed by gas chromatography/mass spectroscopy (GC/MS). The antimicrobial activity of the oil was evaluated against 16 micro‐organisms using agar disc diffusion and broth microdilution methods. RESULTS: Seventy‐three compounds, constituting about 97.56% of the total oil, were identified. The main components were 1,8‐cineole (45.24%), ρ‐propylbenzaldehyde (6.04%), geraniol (5.11%), geranial (4.52%), α‐terpineol (3.59%) and α‐phellandrene (3.07%). The essential oil showed a broad spectrum of antimicrobial activity against all the tested micro‐organisms, including Gram‐positive and Gram‐negative bacteria, and fungi. The oil exerted the strongest bactericidal activity against Staphylococcus aureus CCTCC AB91118, with minimum inhibitory and bactericidal concentrations of 0.20 g L^?1. CONCLUSION: Our study suggests that the Amomum tsao‐ko essential oil could be one of new medicinal resources for antibacterial and antifungal agents. Copyright © 2008 Society of Chemical Industry     

Oregano: chemical analysis and evaluation of its antimalarial, antioxidant, and cytotoxic activities

Abstract: GC‐FID and GC‐MS analysis of essential oil from oregano leaves (Origanum compactum) resulted in the identification of 46 compounds, representing more than 98% of the total composition. Carvacrol was the predominant compound (36.46%), followed by thymol (29.74%) and p‐cymene (24.31%). Serial extractions with petroleum ether, ethyl acetate, ethanol, and water were performed on aerials parts of Origanum compactum. In these extracts, different chemical families were characterized: polyphenols (gallic acid equivalent 21.2 to 858.3 g/kg), tannins (catechin equivalent 12.4 to 510.3 g/kg), anthocyanins (cyanidin equivalent 0.38 to 5.63 mg/kg), and flavonoids (quercetin equivalent 14.5 to 54.7 g/kg). The samples (essential oil and extracts) were subjected to a screening for antioxidant (DPPH and ABTS assays) and antimalarial activities and against human breast cancer cells. The essential oil showed a higher antioxidant activity with an IC₅₀= 2 ± 0.1 mg/L. Among the extracts, the aqueous extract had the highest antioxidant activity with an IC₅₀= 4.8 ± 0.2 mg/L (DPPH assay). Concerning antimalarial activity, Origanum compactum essential oil and ethyl acetate extract showed the best results with an IC₅₀ of 34 and 33 mg/mL, respectively. In addition, ethyl acetate extract (30 mg/L) and ethanol extract (56 mg/L) showed activity against human breast cancer cells (MCF7). The oregano essential oil was considered to be nontoxic.     

琼产艾纳香叶精油的抗氧化和抗菌活性

采用水蒸气蒸馏法收集琼产艾纳香叶精油,经过GC-MS分析,精油中45种化合物被定性检出,主要是单萜类(48.55%)和倍半萜类(39.91%),相对含量列前五位的组分分别是(-)-龙脑(28.45%)、石竹烯(22.98%)、樟脑(9.56%)、α-荜澄茄烯(8.32%)和β-蒎烯(4.32%)。经过DPPH自由基清除试验、β-胡萝卜素漂白试验和硫代巴比妥酸法试验发现精油具有较强的抗氧化活性。琼脂扩散法和琼脂稀释法证实精油对6种受试菌都有抑制活性,对金黄色葡萄球菌、假丝酵母和黄曲霉具有较好的抑制能力(MIC:625μg/mL),对大肠杆菌、李斯特氏菌和沙门氏菌也表现出了抑制能力(MIC:2 500μg/mL)。以上结果证实琼产艾纳香叶精油具有明显的抗氧化和抗菌活性,拥有成为食品和化妆品的天然抗氧化剂及抗菌剂的潜力。     

柠檬果皮精油的化学组成、抗氧化及抑菌活性研究

采用GC-MS法分析经水蒸气蒸馏法所提柠檬果皮精油的化学组分,并对其抗氧化与抑菌活性进行了研究。实验结果表明:鉴定出23种挥发性成分,占精油总量的94.57%,主要为dl-柠檬烯（42.93%）、γ-萜品烯（8.41%）、α-松油醇（6.39%）和E-柠檬醛（6.09%）等;柠檬精油对OH自由基有较好的清除效果,清除率可达95.14%;而对DPPH自由基的清除率在实验条件下最高为34.81%,远低于同浓度的PG和TBHQ。200mg/kg添加量的柠檬精油可延缓猪油和花生油的贮藏期,但略差于同浓度TBHQ和VE的抗氧化效果。抑菌活性实验结果表明柠檬精油对6种供试菌都有一定的抑菌作用,其中对大肠杆菌的抑菌效果最好,其最低抑菌浓度（MIC）为0.1μL/m L。      

Chemical composition,antioxidant and cytotoxicity activities of the essential oils of Myristica fragrans and Morinda citrifolia

BACKGROUND: In this study the chemical composition, antioxidant activities and cytotoxic effect of the essential oils of Myristica fragrans (nutmeg) and Morinda citrifolia (mengkudu) were determined. RESULTS: Thirty‐eight compounds in nutmeg oil and six compounds in mengkudu oil were identified by gas chromatography–mass spectrometry. The free radical scavenging activity of nutmeg oil was superior of that mengkudu oil. The MTT assay of nutmeg oil on human colorectal carcinoma (HCT‐116) and human breast carcinoma (MCF‐7) cell lines showed IC₅₀ values of 78.61 and 66.45 µg mL^?1, respectively. The mengkudu oil exhibited IC₅₀ values of 91.46 and 78.15 µg mL^?1 for HCT‐116 and MCF‐7, respectively. CONCLUSION: The results showed that nutmeg oil can be developed as potent anti‐cancer and antioxidant drugs. Copyright © 2011 Society of Chemical Industry     

草果精油的化学组成、抗氧化及抑菌活性研究

以正己烷为溶剂提取草果精油,利用气相-质谱联用技术（GC-MS）分析其化学成分,同时研究了草果精油的抗氧化和抑菌活性。结果表明,草果精油成分比较复杂,其中有23种化合物被鉴定,主要成分为香叶醇（29.42%）、橙花叔醇（9.87%）、十八碳烯酸（8.62%）等。草果精油对DPPH和ABTS自由基均显示出了较好的清除效果,EC50值分别为3.84、3.20mg/mL;不同浓度的草果精油对5种测试菌都有一定的抑菌作用,其中对大肠杆菌的抑菌效果最好,其最低抑菌浓度（MIC）为2.0mg/mL。      

Chemical composition,antibacterial and antioxidant activity of the essential oils of Metaplexis japonica and their antibacterial components

The aim of this research was to determine the chemical composition, antioxidant and antibacterial properties of the essential oils from Metaplexis japonica and isolation of antibacterial constituents from the essential oils. Results showed that 63 components were identified in essential oils. Phenylethyl alcohol (77.978%), α‐terpineol (31.810%) and docosane (21.644%) were the most abundent constituents of flower oil, leaf oil and fruit oil, respectively. Based on bioactivity‐guided fractionation, three active constituents were isolated and identified as phenylethyl alcohol, α‐terpineol and β‐linalool. Both flower oil and phenylethyl alcohol showed high antibacterial performance, with inhibition zone from 25 ± 0.5 to 11 ± 0.6 mm at highest concentration, and MIC values ranging from 0.125 to 2%. In both DPPH and ABTS assay, the oils showed moderate antioxidant activity. These results indicate potential efficacy of active constituents and essential oils of M. japonica to control food‐borne pathogenic and spoilage bacteria.     

Chemical composition, antioxidant, and antimicrobial activities of essential oil from pine needle (Cedrus deodara)

The chemical composition of essential oil from pine needles (Cedrus deodara) was determined, and its antioxidant and antimicrobial activities were evaluated. Twenty-three components, representing 95.79% of the oil, were identified by gas chromatography mass spectrometry. The main components include α-terpineol (30.2%), linalool (24.47%), limonene (17.01%), anethole (14.57%), caryophyllene (3.14%), and eugenol (2.14%). Pine needle essential oil showed remarkable antioxidant activity in scavenging free radicals, in lipid peroxidation, and in reducing power assays. Moreover, the essential oil revealed strong antimicrobial activity against typical food-borne microorganisms, with minimum inhibitory concentration and minimum bactericidal concentration values of 0.2 to 1.56 and 0.39 to 6.25 μg/mL, respectively. Transmission electron microscope observation ascertained that the bactericidal mechanism of pine needle essential oil may be the induction of cytoplasmic outflow and plasmolysis. These results suggest that the essential oil from pine needles has potential to be used as a natural antioxidant and antimicrobial agent in food processing. PRACTICAL APPLICATION: The present study provides a theoretical basis for the potential application of essential oil from pine needles (C. deodara) to be used as a natural resource of antioxidant and antimicrobial agents in food industry.     

黄花蒿残膏的挥发性成分分析及其抑菌和抗氧化活性研究

采用无水乙醇浸提法提取黄花蒿残膏中的挥发性成分,对其成分进行GC-MS分析,并通过纸片抑菌实验和抗氧化实验对挥发油抑菌和抗氧化活性进行测定。结果表明:黄花蒿残膏挥发油中鉴定出包括石竹烯氧化物（15.27%）、樟脑（8.71%）和冰片（8.57%）在内的29种成分,占总挥发油的81.23%。纸片法抑菌活性测试表明黄花蒿残膏挥发油对四种实验供试菌均有明显的抑制作用,大肠杆菌、金黄色葡萄球菌、鼠伤寒沙门氏菌的最小抑菌浓度为0.5%相似文献   

Antiaflatoxigenic and antioxidant activity of an essential oil from Ageratum conyzoides L.

BACKGROUND: Aflatoxin contamination of various commodities can occur as a result of infection, mainly by Aspergillus flavus and Aspergillus parasiticus. Every year, almost 25% of the world's food supply is contaminated by mycotoxins. Aflatoxins B₁, B₂, G₁ and G₂, which occur naturally, are significant contaminants of a wide variety of commodities. A number of biological activities have been associated with Ageratum conyzoides. We have therefore investigated the antiaflatoxigenic, antioxidant and antimicrobial activity of essential oils of A. conyzoides. This could help to turn A. conyzoides, a nuisance weed, into a resource. RESULTS: The essential oil of Ageratum conyzoides L. shows the presence of 12 compounds when analyzed by gas chromatography–mass spectrometry. The growth and aflatoxin production of the toxigenic strain Aspergillus parasiticus was completely inhibited by essential oil. All the studied concentrations of the oil demonstrate a reduction in mycelia growth and decreased production of different aflatoxins in fungi, as revealed by liquid chomatographic–tandem mass spectrometric analysis. Volatiles from macerated green leaf tissue of A. conyzoides were also effective against A. parasiticus. The strongest antibacterial activity was observed against the bacteria Staphylococcus aureus and Bacillus subtilis in a disk diffusion bioassay. Essential oil and methanol extract of A. conyzoides L. were assayed for their antioxidant activity. Methanol extract showed the highest antioxidant activity in FRAP and DPPH assay, whereas essential oil showed greater lipid peroxidation inhibition than methanol extract. CONCLUSION: The plant's ethno‐medicinal importance, antioxidant potential, inhibitory activity against the Aspergillus group of fungi and production of aflatoxins may add a new dimension to its usefulness in the protection of stored product. Copyright © 2010 Society of Chemical Industry     

Correlative metabolite profiling approach to understand antioxidant and antimicrobial activities from citrus essential oils

The objective of this study was to investigate the chemical composition of the essential oils from citrus species, as well as their antioxidant and antimicrobial activities. By gas chromatography-mass spectrometry, we identified thirty-seven metabolites and a range of unique compounds, contributing to the discrimination of the species. Different biological potentialities were detected depending on the species supported the significant effect of the genetic factor. C. aurantium and C. limon exhibited the highest antioxidant activities which make them a potential source of natural preservative. C. limon exhibited the highest antibacterial activities and C. reticulata the highest antifungal activities. Essential oils extracted from these agro-wastes could serve as natural food preservatives to prevent food pathogens and then extending the shelf life. A set of potential metabolites could be implicated in the observed biological activity, underlying that the antimicrobial activity is a complex trait.