Antimycotic activity of Melaleuca alternifolia essential oil and its major components

AIMS: The aim of this study was to analyse the antimycotic properties of Melaleuca alternifolia essential oil (tea tree oil, TTO) and its principal components and to compare them with the activity of 5-fluorocytosine and amphotericin B. METHODS AND RESULTS: The screening for the antimycotic activity was performed by serial twofold dilutions in Roswell Park Memorial Institute medium with the inclusion of Tween-80 (0.5%). TTO and terpinen-4-olo were the most active compounds. CONCLUSIONS: The majority of the organisms were sensitive to the essential oil, with TTO and terpinen-4-olo being the most active oils showing antifungal activity at minimum inhibitory concentration values lower than other drugs. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides a sample large enough to determine the antifungal properties of TTO and terpinen-4-olo and suggests further studies for a possible therapeutic use.     

竹叶楠叶挥发油的化学成分与抗真菌活性研究

利用 GC- MS联用技术从竹叶楠 (Phoebe faberi)叶挥发油中鉴定了 2 6个萜类化合物 ,如(Z) - (R) - (+) - 3,7,11-三甲基 - 1,6 ,10 -十二碳三烯 - 3-醇 (相对含量 39.34% )、β-丁香烯 (2 9.18% )、姜烯 (5.16 % )和氧化丁香烯 (4 .2 1% )。该挥发油具有一定的体外抗真菌活性 ,在培养基油浓度小于2 .0 μL/ m L的情况下 ,能够完全抑制新型隐球菌、申克氏孢子丝菌、羊毛状小孢子菌、石膏样小孢子菌和球毛壳霉等皮肤真菌的生长繁殖。     

In vitro antiviral activity of Melaleuca alternifolia essential oil

Aims:  To investigate the in vitro antiviral activity of Melaleuca alternifolia essential oil (TTO) and its main components, terpinen-4-ol, α-terpinene, γ-terpinene, p -cymene, terpinolene and α-terpineol.
Methods and Results:  The antiviral activity of tested compounds was evaluated against polio type 1, ECHO 9, Coxsackie B1, adeno type 2, herpes simplex (HSV) type 1 and 2 viruses by 50% plaque reduction assay. The anti-influenza virus assay was based on the inhibition of the virus-induced cytopathogenicity. Results obtained from our screening demonstrated that the TTO and some of its components (the terpinen-4-ol, the terpinolene, the α-terpineol) have an inhibitory effect on influenza A/PR/8 virus subtype H1N1 replication at doses below the cytotoxic dose. The ID₅₀ value of the TTO was found to be 0·0006% (v/v) and was much lower than its CD₅₀ (0·025% v/v). All the compounds were ineffective against polio 1, adeno 2, ECHO 9, Coxsackie B1, HSV-1 and HSV-2. None of the tested compounds showed virucidal activity. Only a slight virucidal effect was observed for TTO (0·125% v/v) against HSV-1 and HSV-2.
Conclusions:  These data show that TTO has an antiviral activity against influenza A/PR/8 virus subtype H1N1 and that antiviral activity has been principally attributed to terpinen-4-ol, the main active component.
Significance and Impact of the Study:  TTO should be a promising drug in the treatment of influenza virus infection.     

Antifungal activity of essential oils and their combinations in in vitro and in vivo conditions

Natural additives are in demand for the control of microbial growth in foods. Several natural compounds including essential oils (EOs) are being explored for food uses. In the present investigation, the antifungal activity of cinnamaldehyde, eugenol, peppermint and clove EOs and their combinations was evaluated against 12 species of Aspergillus, Fusarium, Penicillium and Rhizopus in in vitro and tomato fruit system (in-vivo). The EOs were able to inhibit complete growth of tested fungi at or below 0.6% level and 80?μL of EOs (except peppermint oil) in in vitro condition and tomato system, respectively. The fractional inhibitory studies showed either additive or indifferent effect by combining eugenol and peppermint, and indifferent or antagonist effect by combining the cinnamaldehyde and clove in both in vitro and in vivo studies. The findings may be useful for application of these EOs in foods, but their effects on organoleptic quality of foods need to be investigated.     

覆盆子提取物联合唑类药物抗真菌活性研究

目的 探讨中药覆盆子提取物联合唑类药物的体外抗真菌作用.方法 采用CLSI公布的M27-A方案微量液基稀释法和棋盘式微量稀释法,测定覆盆子提取物单用及联合唑类药物对不同念珠菌的MIC值和FICI指数.结果 覆盆子不同溶液提取物与氟康唑均表现出协同关系,以覆盆子醇提物为例,单用对念珠菌的MIC80测定值范围主要集中在0.16～1.25 mg/mL,与氟康唑合用后表现出协同关系(FICI≤0.5),且MIC80测定值范围降至0.01 ～0.04 mg/mL;合用后的氟康唑抗真菌活性也明显增强.另外,覆盆子醇提物与不同唑类药物合用后均有协同关系,其MIC80测定值由单用时大于10 mg/mL降至0.04 mg/mL.结论 覆盆子醇提物和唑类药物单用时对耐药念珠菌的抑菌作用较弱,但二者合用后表现出明显的协同关系,对耐药念珠菌的抑菌作用明显增强.     

Phytochemical Analysis and in vitro Free‐Radical‐Scavenging Activities of the Essential Oils from Leaf and Fruit of Melaleuca leucadendra L.

The phytochemical profile of Melaleuca leucadendra L. leaf and fruit oils from Cuba was investigated by GC and GC/MS. Forty‐one and sixty‐four volatile compounds were identified and quantified, accounting for 99.2 and 99.5% of the leaf‐oil and fruit‐oil total composition, respectively. The main components were 1,8‐cineol (43.0%), viridiflorol (24.2%), α‐terpineol (7.0%), α‐pinene (5.3%), and limonene (4.8%) in the leaf oil, and viridiflorol (47.6%), globulol (5.8%), guaiol (5.3%), and α‐pinene (4.5%) in the fruit oil. The antioxidant capacity of these essential oils was determined by three different in vitro assays (2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical, thiobarbituric acid reactive species (TBARS), and 2,2′‐Azinobis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS) radical cation), and significant activities were evidenced for all of them.     

美浮特皮肤抗菌液对致足癣真菌抗真菌后效应的体外研究

目的：评价美浮特^R皮肤抗菌液对致足癣真菌皮肤癣菌和白念珠菌的体外抗真菌活性及抗真菌后效应。方法采用美国 CLSI M27-A3和 M38-A2方案测定美浮特皮肤抗菌液对足癣常见致病真菌的最低抑菌浓度（ MIC）;并以白念珠菌（ATCC90028）为指示菌测定美浮特皮肤抗菌液测定时间-杀菌曲线,同时测定其对白念珠菌的抗真菌后效应（post-antifungal effect,PAFE）。结果美浮特皮肤抗菌液对4属6种57株 MIC 的范围为1：40-1：160、MIC50为1：80、MIC90为1：40;对白念珠菌的 MIC 范围为1：40-1：80、对皮肤癣菌的 MIC 范围为1：40-1：160。该抗菌液具有很强的杀菌作用,且随着药物浓度的降低,杀菌速度和程度随之变化。该抗菌液对白念珠菌0.5MIC、MIC、2MIC 的 PAFE 分别为0.85 h、2.1 h、3.59 h;且 PAFE 时间的延长与药物浓度呈正相关。结论美浮特^R皮肤抗菌液对致病真菌皮肤癣菌、白念珠菌具有快速、有效、持续的杀菌作用,该抗菌液对皮肤癣菌较白念珠菌具有更强的抗真菌作用。且该抗菌液对白念珠菌具有较长时间的后效应,可以广泛应用于临床治疗皮肤癣菌及白念珠菌所致的感染。     

In vitro antifungal activity of the tea tree (Melaleuca alternifolia) essential oil and its major components against plant pathogens

AIMS: The aim of this study was to examine the effect of Melaleuca alternifolia essential oil (TTO) and its principal components on four cereal-pathogenic fungi. METHODS AND RESULTS: The antimycotic properties of TTO and of terpinen-4-ol, gamma-terpinen and 1,8-cineole (eucalyptol) were evaluated in vitro on Fusarium graminearum, Fusarium culmorum and Pyrenophora graminea. Moreover, barley leaves infected with Blumeria graminis were treated with whole TTO. All the tested fungi were susceptible to TTO and its components. CONCLUSIONS: TTO exerted a wide spectrum of antimycotic activity. Single TTO purified components were more active than the whole oil in reducing in vitro growth of fungal mycelium and, among the tested compounds, terpinen-4-ol was the most effective. SIGNIFICANCE AND IMPACT OF THE STUDY: TTO and its components can be considered potential alternative natural fungicides.     

Preparation of some pyrazoline derivatives and evaluation of their antifungal activities

The synthesis of a new series of 1-[(benzazole-2-yl)thioacetyl]-3,5-diaryl-2-pyrazoline derivatives was obtained by reacting 1-(chloroacetyl)-3,5-diaryl-pyrazolines with 2-mercaptobenzimidazole/benzoxazole/benzothiazole. The chemical structures of the compounds were elucidated by ¹H-NMR, ¹³C-NMR, and FAB⁺-MS spectral data. Their antifungal activities against Candida albicans, Candida glabrata, Candida utilis, Candida tropicalis, Candida krusei, and Candida parapsilosis were investigated. A significant level of activity was observed.     

In vitro susceptibility of dermatomycoses agents to six antifungal drugs and evaluation by fractional inhibitory concentration index of combined effects of amorolfine and itraconazole in dermatophytes

To investigate the antifungal drug susceptibility of fungi responsible for dermatomycoses, minimum inhibition concentration (MIC) tests were performed in 44 strains of dermatophytes, including Trichophyton rubrum, Trichophyton mentagrophytes, Trichophyton verrucosum, Trichophyton tonsurans, Microsporum canis, Microsporum gypseum and Epidermophyton floccosum, with six antifungal drugs (amorolfine, terbinafine, butenafine, ketoconazole, itraconazole and bifonazole) by broth microdilution assay according to Clinical Laboratory Standard Institute protocols. Six possible dermatomycosis‐causing non‐dermatophytic fungi were also tested. The two major causes of tinea, T. rubrum and T. mentagrophytes, showed significantly different sensitivities to ketoconazole and bifonazole. Clinically derived dermatophytes were sensitive to the six antifungal drugs tested. However, non‐dermatophytes, especially Fusarium spp., tended to be resistant to these antifungal drugs. In Trichophyton spp., the MICs of non‐azole drugs had narrower distributions than those of azoles. To evaluate the effects of antifungal drug combinations, the fractional inhibitory concentration index was calculated for the combination of amorolfine and itraconazole as representative external and internal drugs for dermatophytes. It was found that this combination had synergistic or additive effects on most dermatophytes, and had no antagonistic effects. The variation in susceptibility of clinically derived fungal isolates indicates that identification of causative fungi is indispensable for appropriately choosing effective antifungal drugs in the early stages of infection. The results of combination assay suggest that multiple drugs with different antifungal mechanisms against growth of dermatophytes should be used to treat refractory dermatomycoses, especially onychomycosis.     

In vitro antifungal and antibacterial activities of extracts of Galium tricornutum subsp. longipedunculatum

The aim of this study was to evaluate the antimicrobial activity of crude ethanolic extracts and fractions of the ariel parts and the fruits of Galium tricornutum subsp. longipedunculatum, traditionally used in northern areas of Pakistan for treating microbial infections of skin. Extracts and their fractions were tested against six bacteria and six fungal strains using the hole diffusion method and macrodilution method. All extracts and fractions possessed significant antimicrobial effect. Four fungal strains, Candida albicans, Trichophyton longifusus, Fusarium.solani and Candida glabrata, showed interesting susceptibility profiles when evaluated using the extracts and fractions with MICs ranging from 0.18 to 200 mg/mL. In case of bacterial strains, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi were significantly susceptible to the extracts and fractions with MICs ranging from 0.12 to 200 mg/mL. Comparative results were carried out using imepenem, miconazole and amphotericin B as standard antibiotics.     

加拿大一枝黄花精油的化学成分及其抗菌活性

用GC—MS联用技术分析了加拿大一枝黄花（Solidago canadensis L．）精油的化学组成和含量,并测定了精油对6种农业病原真菌的抗菌活性。从加拿大一枝黄花的精油中鉴定出50种成分,占色谱峰总面积的91．08％,（＋）一大拢牛儿烯D（28．64％）、α-蒎烯（15、08％）、柠檬烯（11．80％）为精油的主要成分。抗菌活性研究结果表明,加拿大一枝黄花精油对水稻纹枯病和黄瓜立枯病的抑制作用最强,对番茄灰霉病显示出中等抑制作用,但对番茄早疫病、菜豆炭疽病和葡萄炭疽病的抑制作用很弱。     

Antibacterial, antifungal, and antiviral activities of the lipophylic extracts of Pistacia vera

In the present study, antibacterial, antifungal, and antiviral properties of 15 lipohylic extracts obtained from different parts (leaf, branch, stem, kernel, shell skins, seeds) of Pistacia vera were screened against both standard and the isolated strains of Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Staphylococcus aureus, Candida albicans and C. parapsilosis by microdilution method. Both Herpes simplex (DNA) and Parainfluenza viruses (RNA) were used for the determination of antiviral activity of the P. vera extracts by using Vero cell line. Ampicilline, ofloxocine, ketoconazole, fluconazole, acyclovir and oseltamivir were used as the control agents. The extracts showed little antibacterial activity between the range of 128-256 microg/ml concentrations whereas they had noticeable antifungal activity at the same concentrations. Kernel and seed extracts showed significant antiviral activity compared to the rest of the extracts as well as the controls.     

Chemical composition and biological activities of essential oils of Salvia officinalis aerial parts as affected by diurnal variations

The main objective of this work is to evaluate the impact of the diurnal variation on the essential oil (EO) of Salvia officinalis and on their antioxidant, antifungal and insecticidal potentials. Obtained results showed that the chemical composition of EOs of sage varied significantly during the day. For the EO, the 7 am extract was characterized by the most significant antiradical activity. The EOs of 12 and 5 pm used at a dose of 10 μL were found to have the most effective potential to inhibit the growth of Botrytis cinerea whereas, the EO of 5 pm used at the same dose (10 μL) was the most effective against Fusarium sambucinum. For the fumigant test, the EO from 7 am had the highest activity against Spodoptera littoralis. The EO of 12 pm had the largest repellency activity against Trogoderma granarium. In addition, the EO from 7 am belongs to the repulsive class III, those of 12 and 5 pm belong to the repulsive class IV. The results of this study indicate how to optimize the best harvesting hour to obtain extracts characterized by the best yield of active compounds and by the more effective biological activity.     

Synthesis,spectral characterization,and in vitro antibacterial and antifungal activities of novel 1,3-thiazine-2-amines comprising morpholine nucleus

A collection of 4-(4-morpholinophenyl)-6-aryl-6H-1,3-thiazin-2-amines (20–28) were synthesized and their in vitro antimicrobial activity was investigated. Compound 21 against P. aeruginosa, 23 against B. subtilis, 24 against V. cholerae and P. aeruginosa, 26 against S. aureus and B. subtilis, 27 against B. subtilis and E. coli, and 28 against all tested bacterial strains exerted excellent antibacterial activity. Compound 20 against A. flavus and Rhizopus, 21, 26 against Rhizopus, 22, 27 against Mucor, 23 against A. flavus, 24 against both A. flavus and Mucor, 25 against all tested strains, and 28 against Rhizopus and M. gypseum exerted excellent antifungal activity.     

Phytochemical analysis and evaluation of antioxidant and anti-acetylcholinesterase activities of Euphorbia dendroides L. (Euphorbiaceae) latex

The aim of this study was to evaluate the antioxidant and anti-acetylcholinesterase properties and phytochemical constituents of the latex from Euphorbia dendroides L. (Euphorbiaceae) growing wild in Sicily. Phytochemical analysis revealed that into E. dendroides latex the triterpenoids were the most abundant among the identified compounds. Furthermore, a high content of polyphenols mainly as phenolic acids, was found. The antioxidant and free-radical scavenging properties, by several in vitro assays such as DPPH, TEAC and FRAP, have been evaluated. The results showed that E. dendroides latex has significant antioxidant activity, as measured by DPPH assay (2927.01?±?98.03 µmols of Trolox equivalent (TE)/100g FW). Reactivity towards ABTS radical cation and ferric-reducing antioxidant power (FRAP) values were 7580.95?±?97.65 µmols of TE/100g FW and 4383.13?±?95.30?μmol of TE/100g FW, respectively. The latex exhibited also significant inhibition of acetylcholinesterase activity with an IC₅₀ value of 4.46 µg/mL (C.L.?=?2.002–9.947). Furthermore, Brine shrimp (Artemia salina) cytotoxicity bioassay showed that the larvae viability was significantly affected at higher concentrations than those capable to induce significant antioxidant and anti-acetylcholinesterase effects (LD₅₀ 25 µg/mL). The results suggest that polyphenols and terpenoids can contribute significantly to antioxidant and anti-acetylcholinesterase activities of E. dendroides latex.     

In vitro kinetics and antifungal activity of various extracts of Terminalia chebula seeds against plant pathogenic fungi

The aim of the present study was to examine the efficacy of various seed extracts of Terminalia chebula as an antifungal potential against certain important plant pathogenic fungi. The organic extracts of methanol, ethyl acetate and chloroform at the used concentration of 1500 ppm/disc revealed remarkable antifungal effect as a fungal mycelial growth inhibitor against Fusarium oxysporum, Fusarium solani, Phytophthora capsici and Botrytis cinerea, in the range of 41.6–61.3%, along with MIC values ranging from 62.5 to 500 μg/ml. Also, the extracts had a strong detrimental effect on spore germination of all the tested plant pathogens along with concentration as well as time-dependent kinetic inhibition of B. cinerea. The results obtained from this study suggest that the natural products derived from Terminalia chebula could become an alternative to synthetic fungicides for controlling such important plant pathogenic fungi.     

Synthesis,characterization and in vitro antimicrobial evaluation of new compounds incorporating oxindole nucleus

New compounds incorporating with the oxindole nucleus were synthesized via the reaction of substituted isatins [5-methyl-, 5-chloro- and 1-hydroxymethyl isatins] with different nucleophiles. The structures of the newly compounds were elucidated on the basis of FTIR, ¹H NMR, ¹³CMR spectral data, GC/MS and chemical analysis. Investigation of antimicrobial activity of the new compounds was evaluated using broth dilution technique in terms of minimal inhibitory concentration (MIC) count against four pathogenic bacteria and two pathogenic fungi. Most of the new compounds are significantly active against bacteria and fungi. MIC showed that compound (4a) possesses higher effect on Gram-positive bacteria Bacillus cereus than the selected antibacterial agent sulphamethoxazole, whereas compound (11c) possesses more activity against Gram-negative bacteria Shigella dysenterie.