Antibacterial activity of the essential oils of myrtle leaves against Erysipelothrix rhusiopathiae

ObjectiveTo evaluate the antibacterial activity of the essential oil of Myrtus communis (M. communis) L. against Erysipelothrix rhusiopathiae (E. rhusiopathiae) in vitro.MethodsWild populations of M. communis collected from Khuzestan and Lorestan provinces, Southwest Iran, were examined for antibacterial activity and chemical variability in leaves. The in vitro antibacterial activity against E. rhusiopathiae was performed by agar disc diffusion and micro-dilution assays.ResultsThe essential oils of M. communis have strong antibacterial against E. rhusiopathiae in both assays. The results showed that the major components of the oil were α-pinene (22.3%-55.2%), 1,8-cineole (8.7%-43.8%) and linalool (6.4%-14.5%). The inhibition zones and MIC values for bacteria which were sensitive to the essential oils of M. communis were in the range of 14.7–27.0 mm and 0.031–0.25 mg/mL, respectively.ConclusionsThis study demonstrates that products with valuable antibacterial activity can be produced from leaves of M. communis against E. rhusiopathiae.     

超临界二氧化碳流体萃取三叶青藤挥发油成分分析

目的采用GC—MS法分析三叶青藤挥发油成分,为其质量评价提供科学依据。方法采用二氧化碳超临界萃取法（SFE—CO2）萃取并分离三叶青藤药材中的挥发油,所提取得到的挥发油运用GC—MS进行分析,用面积归一化法确定其相对含量。结果从三叶青藤药材中提取的挥发油经GC—MS分析,共检测到84个色谱峰,通过NIST库检索一共鉴定出39个化合物的具体结构,占所提取的三叶青藤挥发油总量的56．47％（g／g）,其中棕榈酸、十三烷酸、芳樟醇等在该药材挥发油中占的比例较高。结论该方法提取条件优良,初步揭示了该药材挥发性成分,对进一步研究其化学成分打下基础,为药材的质量评价提供科学参考。     

采收时期、部位、干燥方式对海南罗勒精油质量的影响

目的:探讨采收时期、部位以及干燥方式对海南罗勒精油的影响。方法:采摘海南罗勒(Ocimumbasilicum L.)无花鲜叶(嫩)、含花鲜叶(嫩)、全花、全叶、茎;取新鲜罗勒嫩叶,部分经过冻存、50℃低温烘干或自然风干等处理,再用水蒸气蒸馏法提取精油,以精油收率对上述处理过程进行评价。利用气相色谱或气相色谱-质谱联用技术分析上述所得的精油,利用正交实验法优选罗勒鲜叶水蒸气蒸馏的最佳工艺。结果:无花嫩叶出油率最低,全花出油率最高,顺序是:全花>全叶>含花鲜叶>无花嫩鲜叶,茎中不含精油。鲜叶低温烘干或自然风干比鲜叶和冻存鲜叶的出油率低,约损失35%。精油中主要的物质为沉香醇(34.4%)、丁香酚(19.0%)、甲基胡椒酚(13.4%)等。丁香罗勒鲜叶剪成5cm长、加入5倍量水和提取3h为水蒸气蒸馏的最佳提取工艺。结论:采收时期、部位、干燥方式对海南罗勒精油的质量产生影响,这些信息可为海南罗勒精油的研究开发提供参考。     

五种植物精油熏杀致倦库蚊的效果

目的:考察菊科植物、芸香科植物、椒样薄荷、留兰香和香茅共5种植物的精油对致倦库蚊的熏蒸杀虫效果.方法:以三角瓶密闭熏蒸法测定5种精油对致倦库蚊的熏杀效果.结果:持续熏蒸不同时间后,5种精油对致倦库蚊的毒力有差异.在熏蒸0.5、4和24h后芸香科植物精油均毒力最大,其LC50分别为0.013、0.055、0.058.而菊科植物精油毒力最小,其3个时间段的LC50分别为0.948、0.427、1.711.用供试植物精油的LC95剂量(0.5h)熏蒸处理致倦库蚊,显示留兰香油的熏杀速度最快,其LT50值为6.087min,而香茅油的最慢,为21.143 min.结论:5种植物精油对致倦库蚊均具有一定的熏杀活性,以芸香科植物精油和留兰香油的杀虫效果较好,为其现场实验提供了基础资料.     

Effect of essential oils on Aspergillus spore germination,growth and mycotoxin production: a potential source of botanical food preservative

ObjectiveTo investigate effect of essential oils on Aspergillus spore germination, growth and mycotoxin production.MethodIn vitro antifungal and antiaflatoxigenic activity of essential oils was carried out using poisoned food techniques, spore germination assay, agar dilution assay, and aflatoxin arresting assay on toxigenic strains of Aspergillus species.ResultsCymbopogon martinii, Foeniculum vulgare and Trachyspermum ammi (T. ammi) essential oils were tested against toxicogenic isolates of Aspergillus species. T. ammi oil showed highest antifungal activity. Absolute mycelial inhibition was recorded at 1 μl/mL by essential oils of T. ammi. The oil also showed, complete inhibition of spore germination at a concentration of 2 μl/mL. In addition, T. ammi oil showed significant antiaflatoxigenic potency by totally inhibiting aflatoxin production from Aspergillus niger and Aspergillus flavus at 0.5 and 0.75 μl/mL, respectively. Cymbopogon martinii, Foeniculum vulgare and T. ammi oils as antifungal were found superior over synthetic preservative. Moreover, a concentration of 5 336.297 μl/kg body weight was recorded for LC50 on mice indicating the low mammalian toxicity and strengthening its traditional reputations.ConclusionsIn conclusion, the essential oils from T. ammi can be a potential source of safe natural food preservative for food commodities contamination by storage fungi.     

Larvicidal efficacy of Ethiopian ethnomedicinal plant Juniperus procera essential oil against Afrotropical malaria vector Anopheles arabiensis (Diptera: Culicidae)

ObjectiveTo screen the essential oil of Juniperus procera (J. procera) (Cupressaceae) for larvicidal activity against late third instar larvae of Anopheles arabiensis (An. arabiensis) Patton, the principle malaria vector in Ethiopia.MethodsThe essential oil of J. procera was evaluated against the larvae of An. arabiensis under the laboratory and semi-field conditions by adopting the World Health Organization standard protocols. The larval mortality was observed for 24 h of post exposure.ResultsThe essential oil of J. procera has demonstrated varying degrees of larvicidal activity against An. arabiensis. The LC₅₀ and LC₉₀ values of J. procera were 14.42 and 24.65 mg/L, respectively under the laboratory conditions, and from this data, a Chi-square value 6.662 was observed to be significant at the P=0.05 level. However, under the semi-field conditions the LC₅₀ and LC₉₀ values of J. procera were 24.51 and 34.21 mg/L, respectively and a Chi-square value 4.615 was significant at the P=0.05 level. The observations clearly showed that larval mortality rate is completely time and dose-dependent as compared with the control.ConclusionsThis investigation indicates that J. procera could serve as a potential larvicidal agent against insect vector of diseases, particularly An. arabiensis. However further studies are strongly recommended for the identification of the chemical constituents and the mode of action towards the rational design of alternative promising insecticidal agents in the near future.     

In vitro antioxidant and cytotoxic activities of essential oil of Feronia elephantum Correa

ObjectiveTo analyse the chemical composition and evaluation of antioxidant, cytotoxic and DNA fragmentation activities of essential oil of Feronia elephantum Correa.MethodsChemical composition analysis of hydrodistilled essential oil was determined by gas chromatography-mass spectrometry and in vitro antioxidant activity of oil was determined by DPPH free radical, hydroxyly radical scavenging, metal chelating and prevention of deoxyribose degradation. Cytotoxicity and DNA fragmentation activities against breast cancer cells (MCF-7) were also analyzed.ResultsGas chromatography-mass spectrometry analysis revealed the presence of 24 compounds with caryophyllene oxide (62.29%) as major compound. A considerable antioxidant, cyotoxic and DNA fragmentation activities of oils was observed.ConclusionsThe result of this study clearly indicates oil could be useful for food preservation and preparation.     

益智仁盐炙前后挥发油的GC-MS分析及抗乙酰胆碱酯酶活性测定

目的 对临床治疗老年痴呆方剂中的常用中药益智仁盐炙前后挥发油的化学成分进行比较,并评价其对乙酰胆碱酯酶(AChE)的抑制活性。方法 采用水蒸气蒸馏法提取挥发油,运用气相色谱-质谱(GC-MS)联用法对挥发油化学成分进行分析,利用薄层色谱(TLC)生物自显影技术评价挥发油的乙酰胆碱酯酶抑制活性。结果 益智仁经盐炙后,挥发油提取率降低。从益智仁盐炙前后的挥发油中分别鉴定出29种化学成分,其中圆柚酮含量最高,其次为瓦伦亚烯;炮制前后挥发油中四个成分发生了变化:菖蒲烯、喇叭茶醇、氧化石竹烯和香附子烯仅在生益智仁中检出;而桉叶-11烯-1a-醇、9,10-脱氢异长叶烯、古芸烯环氧化物、1R,4R,7R,11R-1,3,4,7-四甲基三环[5.3.1.0(4,11)]-十一-2-烯仅在盐益智仁中检出。盐炙前后益智仁挥发油成分均具有一定的乙酰胆碱酯酶抑制活性。结论 益智仁盐炙前后挥发油成分有部分变化,盐炙可除去喇叭茶醇这一潜在的毒性倍半萜类成分;益智仁挥发油的乙酰胆碱酯酶抑制活性可能与其治疗老年痴呆作用密切相关。     

Antibacterial activity of the essential oils from the leaves of Eucalyptus globulus against Escherichia coli and Staphylococcus aureus

Objective

To examine the in vitro antimicrobial activities of essential oil of the leaves of Eucalyptus globulus (E. globulus).

Methods

The essential oils of this plant were obtained by the hydrodistillation method. The inhibitory effects of this essential oil were tested against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) by using agar disc diffusion and dilution broth methods.

Results

The results obtained showed that essential oil of the leaves of E. globulus has antimicrobial activity against gram negative bacteria (E. coli) as well as gram positive bacteria (S. aureus).

Conclusion

The encouraging results indicate the essential oil of E. globulus leaves might be exploited as natural antibiotic for the treatment of several infectious diseases caused by these two germs, and could be useful in understanding the relations between traditional cures and current medicines.     

超临界CO_2流体萃取华凤仙挥发油成分分析研究

目的分析华凤仙药材挥发油化学成分,为进一步研究其化学成分提供理论参考。方法采用二氧化碳超临界萃取法（SFE-CO2）提取华凤仙挥发油,用气相色谱-质谱联用法分析鉴定其化学成分,用面积归一化法确定其相对含量。结果在华凤仙药材挥发油中,共检出52个化合物,鉴定了其中27个化合物。含量较高的为正二十六烷、正十六烷酸乙酯等。结论本研究为首次采用气相色谱-质谱联用法对凤仙药材挥发油进行成分分析,该方法快捷、简便,为进一步研究该药材的化学成分提供参考。     

白豆蔻、望春花和高良姜挥发油驱蚊活性的评价

目的评价白豆蔻、望春花和高良姜挥发油的驱蚊活性。方法用实验室人体驱避试验评价纯挥发油对白纹伊蚊的驱避活性。结果白豆蔻、望春花和高良姜纯挥发油的有效保护时间分别为0．5—1．0h、1．0～1．5h和2．0～2．5h。结论三种植物的挥发油具有用于研制驱蚊剂的潜力。     

新鲜海南柠檬草精油的GC-MS分析

目的:研究新鲜海南产柠檬草精油的化学成分。方法:采用水蒸气蒸馏法提取柠檬草精油,运用气质谱联用(GC-MS)技术对挥发油成分进行分析,并采用峰面积归一化法确定各成分的相对百分含量。结果:共鉴定出12种成分,其中相对百分含量超过2%的有香叶醛(49.35%)、橙花醛(29.52%)、香叶醇(8.28%)、乙酸香叶酯(3.16%)、棕榈酸(2.64%)及橙花醇(2.56%)等。结论:新鲜海南柠檬草精油中主要成分为柠檬醛,百分含量高达78.87%。     

Antioxidant properties and inhibitory effects of Satureja khozestanica essential oil on LDL oxidation induced-CuSO4 in vitro

Objective

To assess various antioxidative activities of Satureja khozestanica essential oil (SKE) and its effect on oxidation of low density lipoprotein (LDL) induced by CuSO₄ in vitro by monitoring the formation of conjugated dienes and malondialdehyde (MDA).

Methods

The formation of conjugated dienes, lag time and MDA were measured. Inhibition of this Cu-induced oxidation was studied in the presence of several concentrations of SKE. Also total antioxidant activity and free radical scavenging of SKE were determinated.

Results

It was demonstrated that SKE was able to inhibit LDL oxidation and decrease the resistance of LDL against oxidation. The inhibitory effects of SKE on LDL oxidation were dose-dependent at concentrations ranging from 50 to 200 µg/mL. Total antioxidant capacity of SKE was (3.20±0.40) nmol of ascorbic acid equivalents/g SKE. The SKE showed remarkable scavenging activity on 2, 2-diphenyl-picrylhydrazyl, IC₅₀ (5.30±0.11) ng/mL.

Conclusions

This study shows that SKE is a source of potent antioxidants and prevents the oxidation of LDL in vitro and it may be suitable for use in food and pharmaceutical applications.     

Essential oils of Origanum compactum increase membrane permeability,disturb cell membrane integrity,and suppress quorum-sensing phenotype in bacteria

The aim of this study was to investigate antibacterial activity of Origanum compactum essential oils collected at three phenological stages on Escherichia coli and Bacillus subtilis. The antibacterial activity was evaluated using the agar-well diffusion assay. The MIC and MBC values were determined using the micro-dilution assay. The investigation of the antibacterial action was carried out by the evaluation of the effect of O. compactum essential oils on the antibacterial kinetic growth, the integrity of cell membrane and permeability of the cell membrane. The anti-quorum sensing activity was tested by the inhibition of the biofilm formation. The findings of this study showed that O. compactum essential oil has potent antibacterial activities against E. coli and B. subtilis. The lowest inhibition value against B. subtilis was obtained with O. compactum essential oil at the post-flowering stage (MIC = MBC = 0.0312% (v/v)). The antibacterial mechanisms of O. compactum essential oils are related to the disturbing of the cell membrane integrity and the increasing of the membrane permeability, which leads to the leakage of genetic materials (DNA and RNA). Moreover, O. compactum essential oils inhibited the formation of the biofilms, a phenotype that has been known to be quorum sensing regulated.     

海南产温莪术挥发油成分分析

目的：分析海南产温莪术挥发油的化学成分,为其资源利用和质量评价提供依据。方法采用水蒸气蒸馏法提取挥发油,以海南产的温莪术挥发油和浙江产的温莪术挥发油为研究对象,采用GC-MS法、HPLC色谱法,根据《中国药典》公布的莪术油的质量标准分析其挥发油的化学成分。结果海南产温莪术挥发油与浙江产温莪术挥发油的成分基本一致,两种挥发油的特征图谱与《中国药典》2010年版公布的莪术油的特征图谱比对,相似度均达到95%以上。结论不同产地的温莪术挥发油成分有一定的差异,但主要成分基本相同,为海南产温莪术的开发利用提供了科学依据。     

艾叶挥发油提取工艺的优化

目的：通过正交试验法优化艾叶挥发油提取工艺。方法采用正交试验法考察工艺,其中考察因素为提取时间（A）、料液比（B）和浸泡时间（C）,每个因素取3个水平,以得油率为考察指标对艾叶挥发油的提取工艺进行优选。结果艾叶挥发油最佳提取条件为料液比1：10、浸泡4 h、提取3 h,平均得油率为0.416%,RSD=2.64%（n=3）。结论优选的提取工艺得油率较高,工艺稳定可行,可为实际生产提供依据。     

迷迭香精油水蒸气蒸馏最佳提取工艺筛选研究

目的:探讨优选迷迭香精油水蒸气蒸馏提取工艺.方法:采用正交设计法,以出油率、α-蒎烯含量及1,8-按叶素含量等多指标综合评价,优化提取工艺.结果:最佳提取工艺为迷迭香不粉碎.30倍量水,提取4 h.结论:优选的迷迭香精油水蒸气蒸馏提取工艺稳定有效.     

不同方法提取草果挥发油的化学成分

目的:研究用不同方法提取的草果挥发油的化学成分变化。方法:通过微波、超声辅助萃取和水蒸气蒸馏提取草果挥发油,用正交实验法研究各种方法的最佳提取条件,运用GC/MS法分析鉴定不同方法提取草果挥发油的化学成分。结果:3种提取方法的最高收率分别是4.50%(微波萃取)、3.82%(超声萃取)、2.75%(水蒸气蒸馏),3种方法共分离出39种化合物,主要为单萜类化合物。结论:3种方法提取挥发油的化学成分、指纹图谱均相似,在快速提取挥发油时可以采用微波、超声辅助提取。     

Larvicidal efficacies and chemical composition of essential oils of Pinus sylvestris and Syzygium aromaticum against mosquitoes

Objective

To assess the chemical composition and mosquito larvicidal potentials of essential oils of locally sourced Pinus sylvestris (P. sylvestris) and Syzygium aromaticum (S. aromaticum) against Aedes aegypti (A. aegypti) and Culex quinquefasciatus (C. quinquefasciatus).

Method

The chemical composition of the essential oils of both plants was determined using GC-MS while the larvicidal bioassay was carried out using different concentrations of the oils against the larvae of A. aegypti and C. quinquefasciatus in accordance with the standard protocol.

Results

The results as determined by GC-MS showed that oil of S. aromaticum has eugenol (80.5%) as its principal constituent while P. sylvestris has 3-Cyclohexene-1-methanol, .alpha., .alpha.4-trimethyl (27.1%) as its dominant constituent. Both oils achieved over 85% larval mortality within 24 h. The larvae of A. aegypti were more susceptible to the oils [LC₅₀ (S. aromaticum)=92.56 mg/L, LC₅₀(P. sylvestris)=100.39 mg/L] than C. quinquefasciatus [LC₅₀(S. aromaticum)=124.42 mg/L; LC₅₀(P. sylvestris)=128.00 mg/L]. S. aromaticum oil was more toxic to the mosquito larvae than oil of P. sylvestris but the difference in lethal concentrations was insignificant (P>0.05).

Conclusion

The results justify the larvicidal potentials of both essential oils and the need to incorporate them in vector management and control.