枳实、枳壳挥发油化学成分及抑菌活性的比较研究

目的:对比分析不同生长期枳实、枳壳挥发油成分差异,比较不同生长期枳实、枳壳挥发油的抑菌活性。方法:采用药典甲法提取挥发油,通过GC-MS分析枳实、枳壳挥发油的组成;结合枳实、枳壳挥发油的成分差异,对二者挥发油的抑菌活性进行了初步比较研究。结果:枳壳挥发油的抑菌活性总体上较枳实挥发油强。结论:同一来源的枳实、枳壳因生长期不同,挥发油成分和抑菌活性均存在差异。     

薰衣草及橙花精油体外抑菌作用的研究

目的探讨薰衣草精油（Lavender）、橙花精油（Neroli）的体外抑菌作用。方法采用纸片扩散法和连续稀释法对精油体外抑菌活性进行测定。结果薰衣草精油对金黄色葡萄球菌、表皮葡萄球菌、大肠埃希菌、乙型溶血念球菌和白色念珠菌的平均抑菌圈大小分别为：12.00、9.00、10.00、9.50、12.50 mm,最低抑菌浓度（M IC）分别为：217.95、871.80、435.90、871.80、217.95g.L-1。橙花精油对上述5种菌的平均抑菌圈大小分别为：34.75、8.00、12.00、13.75、36.75 mm,M IC分别为：123.93、991.40、991.40、123.93、123.93 g.L-1。其中薰衣草精油对5种菌的抑菌活性强度为：金黄色葡萄球菌〉白色念珠菌、大肠埃希菌〉乙型溶血念球菌、表皮葡萄球菌,橙花精油对5种菌的抑菌活性强度为：金黄色葡萄球菌、白色念珠菌、乙型溶血念球菌〉大肠埃希菌、表皮葡萄球菌。结论薰衣草精油、橙花精油均有一定程度的抑菌效果,可做为天然抑菌剂开发利用。     

Antimicrobial and antioxidant activities of three Mentha species essential oils

The present study describes the antimicrobial activity and free radical scavenging capacity (RSC) of essential oils from Mentha aquatica L., Mentha longifolia L., and Mentha piperita L. The chemical profile of each essential oil was determined by GC-MS and TLC. All essential oils exhibited very strong antibacterial activity, in particularly against Esherichia coli strains. The most powerful was M. piperita essential oil, especially towards multiresistant strain of Shigella sonei and Micrococcus flavus ATTC 10,240. All tested oils showed significant fungistatic and fungicidal activity [expressed as minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) values, respectively], that were considerably higher than those of the commercial fungicide bifonazole. The essential oils of M. piperita and M. longifolia were found to be more active than the essential oil of M. aquatica. Especially low MIC (4 microL/mL) and MFC (4 microL/mL) were found with M. piperita oil against Trichophyton tonsurans and Candida albicans (both 8 microL/mL). The RSC was evaluated by measuring the scavenging activity of the essential oils on the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and OH radicals. All examined essential oils were able to reduce DPPH radicals into the neutral DPPH-H form, and this activity was dose-dependent. However, only the M. piperita oil reduced DPPH to 50 % (IC50 = 2.53 microg/mL). The M. piperita essential oil also exhibited the highest OH radical scavenging activity, reducing OH radical generation in the Fenton reaction by 24 % (pure oil). According to GC-MS and TLC (dot-blot techniques), the most powerful scavenging compounds were monoterpene ketones (menthone and isomenthone) in the essential oils of M. longifolia and M. piperita and 1,8-cineole in the oil of M. aquatica.     

New green solutions against bacterial resistance: palmarosa (Cymbopogon martini) essential oil and quorum sensing

This study aimed to determine the phytochemical content of palmarosa (Cymbopogon martini) essential oil and tested for its antibacterial and anti-quorum sensing activity. The possible inhibition effect by molecular modeling was also revealed. It was recorded that geraniol (81.25%) is the main component of palmarosa essential oil and found effective against Gram-positive and Gram-negative bacteria. The essential oil was found to reduce pyocyanin production (by 71%), elastase activity (by 64%), swarming motility (by 69%), and biofilm formation (by 64%). Furthermore, geraniol was docked against the binding region of the LasR protein and found to excellently bound with the receptor. These results showed that palmarosa essential oil acts as a green solution by exerting potential antibacterial activity against most bacteria and has a significant anti-quorum sensing effect on Pseudomonas aeruginosa PAO1 via geraniol.     

茶树油化学成分及抗菌作用研究

目的:考察茶树油的化学组成成分及抗菌作用.方法:采用气相色谱-质谱联用对茶树油化学成分进行分析,并对茶树油抗菌作用进行初步研究.结果:对茶树油的34种化学成分进行了定量、定性分析,主要化学成分4-羟基萜烯含量占34.66%,初步抗菌实验结果显示茶树油有良好的抑菌作用.结论:海南产茶树油主要抗菌成分4-羟基萜烯含量高,有进一步的开发利用价值.     

Antimicrobial activity of essential oil from Hoslundia opposita.

The essential oil from the leaves of Hoslundia opposite was extracted by hydrodistillation. GC/MS analysis of the volatile oil showed that it contains largely the sesquiterpenes and sesquiterpene alcohols. The essential oil was tested against eight different bacterial species and one fungal species. The antibacterial and antifungal properties of the essential oil from Hoslundia opposite were determined by using seeded agar plates with wells into which was placed the oil, and flasks of yeast extract and sucrose broth for mycelial growth of Aspergillus niger. After incubation for 24 hours, the diameter of the inhibition zone was measured for the antibacterial tests and after seven days, the dry weight of the mycelia was measured and a percentage of inhibition calculated using controls where no samples were added. The results obtained showed that the essential oil from this plant has significant activity against Aspergillus niger, Acinetobacter calcoacetica, Brochothrix thermosphacta and Flavobacterium suaveolens. These were most affected by the volatile oil from Hoslundia opposita.     

The formulation of an effective topical antibacterial product containing Ocimum gratissimum leaf essential oil

The antibacterial potential of Ocimum gratissimum essential oil was explored. Liquid and semisolid formulations of the oil were designed in a variety of bases for topical antiseptic medication. The products were evaluated by agar diffusion assay against type strains and clinical isolates from boil, wound and pimples. Remarkable antibacterial effects, higher than those of commercial antiseptic products, were demonstrated at 2% Ocimum oil concentration in some bases. The properties of base into which the oil was incorporated affected its activity. It was more effective in hydrophilic bases than in lipophilic bases. Solubilization and microemulsification grossly reduced its activity.     

Synergistic interaction and mode of action of Citrus hystrix essential oil against bacteria causing periodontal diseases

Context: Citrus hystrix de Candolle (Rutaceae), an edible plant regularly used as a food ingredient, possesses antibacterial activity, but there is no current data on the activity against bacteria causing periodontal diseases.

Objective: C. hystrix essential oil from leaves and peel were investigated for antibiofilm formation and mode of action against bacteria causing periodontal diseases.

Materials and methods: In vitro antibacterial and antibiofilm formation activities were determined by broth microdilution and time kill assay. Mode of action of essential oil was observed by SEM and the active component was identified by bioautography and GC/MS.

Results and discussion: C. hystrix leaves oil exhibited antibacterial activity at the MICs of 1.06?mg/mL for P. gingivalis and S. mutans and 2.12?mg/mL for S. sanguinis. Leaf oil at 4.25?mg/mL showed antibiofilm formation activity with 99% inhibition. The lethal effects on P. gingivalis were observed within 2 and 4?h after treated with 4?×?MIC and 2?×?MIC, respectively. S. sanguinis and S. mutans were completely killed within 4 and 8?h after exposed to 4?×?MIC and 2?×?MIC of oil. MICs of tested strains showed 4 times reduction suggesting synergistic interaction of oil and chlorhexidine. Bacterial outer membrane was disrupted after treatment with leaves oil. Additionally, citronellal was identified as the major active compound of C. hystrix oil.

Conclusions: C. hystrix leaf oil could be used as a natural active compound or in combination with chlorhexidine in mouthwash preparations to prevent the growth of bacteria associated with periodontal diseases and biofilm formation.     

Antimicrobial activity of the essential oil and some isolated sulfur-rich compounds from Scorodophloeus zenkeri

The essential oil and several pure sulfur compounds isolated from Scorodophloeus zenkeri were tested for their antibacterial and antifungal activity using a paper disc method, the poisoned food technique, a microatmosphere method and the measurement of cellular ATP content. The essential oil completely inhibited the growth of all fungi tested including yeasts, with the exception of Aspergillus flavus, and was active against the Gram-positive bacteria studied, but not the Gram-negative organisms. 2,4,5,7-Tetrathiaoctane, 2,4,5,6,8-pentathianonane, 2,3,4,6,8-pentathianonane, 2,3,5,6,8,10-hexathiaundecane, 2,3,5-trithiahexane 5-oxide, 2,4,5,7-tetrathiaoctane 2-oxide, 2,3,5,7-tetrathiaoctane 3,3-dioxide and 2,3,5-trithiahexane 3,3-dioxide differed in their effects on the strains studied with respect to both growth and synthesis of cellular ATP. 2,3,5-Trithiahexane, 2,3,4,6-tetrathiaheptane, methyl methanethiosulfonate and bis-methyl-sulfonylmethane exhibited no antimicrobial activity.     

A Study of the Antibacterial Activity of the Essential Oil of Lemon Grass (Cymbopogon citratus (DC.) Stapf)

Abstract

Lemon grass oil obtained by the steam distillation of the fresh aerial parts of Cymbopogon citratus (DC.) Stapf was investigated for antibacterial activity. The results obtained suggests that the oil possesses rapid bactericidal activity against Gram-negative and Gram-positive bacteria, the latter being more susceptible. Other factors that could affect the activity of the oil were also investigated. The dispersion of the oil in a dilution of dimethyl sulphoxide which does not have an effect on the microorganisms studied provided a convenient medium for the assay. It is being suggested that more information about the antibacterial activity of essential oils could be obtained using such a methodology.     

百里香精油的化学成分分析及其抗菌活性

目的：分析百里香精油的化学成分及其抗菌活性。方法：采用气相色谱一质谱联用技术（GC—MS）鉴定百里香精油的化学成分,并采用琼脂扩散法考察其对大肠杆菌及金黄色葡萄球菌的抑菌直径。结果：百里香精油共分离出23个峰,鉴定出其中9种化学成分,主要是百里香酚（44．36％）和对伞花烃（31．04％）;百里香精油对大肠杆菌和金黄色葡萄球菌的抑菌直径分别是32mm±0．5mm和40．5mm±1．0mm。结论：百里香精油主要成分是百里香酚和对伞花烃,其对大肠杆菌和金黄色葡萄球菌具有较强的抗菌活性。     

蜡梅不同部位精油化学成分分析及其体外抑菌活性研究

目的 研究蜡梅Chimonanthus praecox（Linn.）Link根、叶、果皮中精油的化学组成及其抑菌活性。方法 采用气相色谱-质谱联用（GC-MS）技术对水蒸气蒸馏法提取的蜡梅根、叶、果皮精油进行成分分析,并分别采用肉汤二倍稀释法和菌丝生长法测试蜡梅不同部位精油对细菌和病原真菌的抑制活性。结果 鉴定了蜡梅根精油中的37种成分、蜡梅叶精油中的48种成分、蜡梅果皮精油中的38种成分,蜡酶不同部位精油中具有相同的化合物15种,分别占各部位精油总量的84.05%,36.83%,64.46%。抑菌实验结果表明蜡梅不同部位精油对受试菌均有不同强度的抑制作用。结论 蜡梅根精油对革兰氏阳性菌和病原真菌具有较强的抑菌活性,抑菌谱较广,且该精油含有多种生物活性成分,具有较高的药用价值及开发前景。     

Antimicrobial Activity of the Extracts and Essential Oil of Viguiera dentata

Viguiera dentata (Cav.) Sprenguel (Asteraceae) is known as “chimalacate” in several Mexican states. Infusions of the aerial part of this species are used for the treatment of baby rash by the inhabitants of San Rafael, Coxcatlan, Puebla, Mexico. We examined the antibacterial and antifungal activities through the disk-diffusion method. The composition and antimicrobial activity of the essential oil of V. dentata is reported here for the first time. The essential oil of aerial parts of V. dentata was examined by GC-MS: it is constituted mainly by monoterpenes (57.16%), and of this the major components are 1,3,3-trimethyl-tricyclo[2.2.1.02,6] heptane (30.85%) and limonene (13.27%). Gram-positive and Gram-negative bacteria were sensitive to the essential oil. The essential oil had no antifungal activity. The hexane extract H₁ presented antibacterial activity against seven strains (four Gram-positive and three Gram-negative); this extract had no antifungal activity. One bioactive compound, ent-kaur-16-en-19-oic acid 1, was isolated. In comparison with the essential oil and H₁, the pure compound 1 showed the lowest MICs in the majority of the bacterial strains. Only the hexane partition (H₂) of the methanol extract showed antifungal activity against all tested fungi.     

Antibacterial activity and chemical composition of essential oil of Chrysanthemum boreale

The essential oil of Chrysanthemum boreale Makino was analyzed by means of GC and GC-MS. Eighty-seven constituents were identified, representing 94.13 % of the total oil and the major components were camphor, alpha-thujone, cis-chrysanthenol, 1,8-cineole, alpha-pinene, and beta-caryophyllene. Furthermore, the essential oil exhibited antibacterial activity (MIC, more than 800 microg/mL versus 0.125 microg/mL for ampicillin) after it was tested against 6 Gram(+) bacteria and 8 Gram(-) bacteria.     

Chemical composition and antibacterial activity of the rhizome oil of Hedychium larsenii

The composition of essential oil from the rhizomes of Hedychium larsenii M. Dan & Sathish was examined by GC-FID and GC-MS techniques. 99% of the oil consisted of monoterpenoids. Sesquiterpenoids were present only in negligible quantities. Linalool and 1,8-cineole were identified as the major components. The oil showed moderate antibacterial activity against Gram-positive and Gram-negative bacteria.     

Comparative study on the in vitro antibacterial activity of Australian tea tree oil, cajuput oil, niaouli oil, manuka oil, kanuka oil, and eucalyptus oil.

To compare the antibacterial activity of the Australian tea tree oil (TTO) with various other medicinally and commercially important essential myrtaceous oils (cajuput oil, niaouli oil, kanuka oil, manuka oil, and eucalyptus oil) the essential oils were first analysed by GC-MS and then tested against various bacteria using a broth microdilution method. The highest activity was obtained by TTO, with MIC values of 0.25% for Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Salmonella choleraesuis, Shigella flexneri, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, S. saprophyticus, and S. xylosus. It is noteworthy that manuka oil exhibited a higher activity than TTO against gram-positive bacteria, with MIC values of 0.12%. Both TTO and manuka oil also demonstrated a very good antimicrobial efficacy against various antibiotic-resistant Staphylococcus species. Pseudomonas aeruginosa was resistant to all essential oils tested, even at the highest concentration of 4%.     

Essential Oil Composition and Antibacterial Studies of Vitex negundo Linn. Extracts

Essential oils from fresh leaves, flowers and dried fruits of Vitex negundo were obtained by hydrodistillation. Using Soxhlet extractor five successive extracts from dried and powdered leaves were also taken. The chemical constituents of essential oil of leaves, flowers and dried fruits were analyzed by GC-FID and GC/MS techniques. Main constituents identified in leaves oil were δ-guaiene, carryophyllene epoxide and ethyl-hexadecenoate; in flowers oil - α-selinene, germacren-4-ol, carryophyllene epoxide and (E)-nerolidol while fruit oil showed β-selinene, α-cedrene, germacrene D and hexadecanoic acid as the main constituents. β-Caryophyllene was only the constituent identified as common to all three oils. α-Guaiene and guaia-3,7-diene were identified as common constituents in leaf and dried fruit oil while leaf and flower oils showed p -cymene, valencene, caryophyllene epoxide and (E)-nerolidol as common constituent. All the essential oils and successive extracts were evaluated for antibacterial potential against Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa bacterial strains. Each of the essential oils and extracts were found to give promising results against B. subtilis and E. coli. Ethyl acetate and ethanol extracts showed prominent antibacterial activity against all the tested strains. Fruits and leaves oil were found to be most active against E. coli and S. aureus, respectively. Only flowers oil was found to be active against P. aeruginosa.     

Composition and antimicrobial activity of the essential oil of Baccharis notosergila

The essential oil of the aerial parts of Baccharis notosergila was examined by GC and GC-MS. Thirty-one constituents were identified representing 96.4% and alpha-pinene, limonene, beta-caryophyllene, and spathulenol were found to be the major components. Furthermore, the oil was tested against eight gram-positive and -negative bacteria and it was found that they exhibited moderate antibacterial activity.     

Chemical characterization and synergistic antibiotic activity of volatile compounds from the essential oil of Vanillosmopsis arborea

Essential oils have been traditionally used for respiratory tract infections, and are used nowadays as ethnic medicines for colds. The objective of this work was to study the antibiotic-modifying activity of the essential oil from the leaves of Vanillosmopsis arborea Baker using gaseous contact. Stems of Vanillosmopsis arborea Baker (Asteracea) were subjected to hydrodistillation, and the essential oil extracted was evaluated for antibacterial and antibiotic-modifying activity by gaseous contact. The volatile components of the oil enhanced the sensitivity of Staphylococcus aureus ATCC 12692 and Proteus vulgaris ATCC 13315 to two or more antibiotics assayed. The activity of the antibiotic gentamicin was increased only in S. aureus. The activity of tetracycline and tobramycin was enhanced against both strains. The essential oil of Vanillosmopsis arborea influences the activity of antibiotics and may be used as an adjuvant in antibiotic therapy against respiratory tract bacterial pathogens.     

丁香精油的提取及其抗菌作用研究

目的考察丁香精油(挥发油)的提取方法及其抗菌活性。方法采用连续回流萃取等不同方法提取丁香精油，并应用平板法考察不同浓度提取物样品对大肠埃希菌、金黄色葡萄球菌、铜绿假单胞菌的抗菌作用。结果应用不同方法所得的丁香精油4种提取物对3种供试菌均有一定的抑制作用，且抗菌作用均随着浓度的降低而减弱，4种提取物对大肠埃希菌的作用普遍较强，而对铜绿假单胞菌和金黄色葡萄球菌的作用稍弱。结论丁香精油气味芬芳怡人，抗菌作用显著，资源丰富，有一定的实用价值。