Chemical and biological characteristics of Cuminum cyminum and Rosmarinus officinalis essential oils

Essential oils extracted by hydrodistillation from Cuminum cyminum and Rosmarinus officinalis were characterized by means of GC and GC–MS. C. cyminum and R. officinalis contained α-pinene (29.1%, 14.9%), 1,8-cineole (17.9%, 7.43%) and linalool (10.4%, 14.9%), respectively, as the major compounds. C. cyminum oil exhibited stronger antimicrobial activity than did R. officinalis oil against E. coli, S. aureus and L. monocytogenes. Complete death time on exposure to Cuminum cyminum L. and Rosmarinus officinalis L. oils were 20 and 25 min 180 and 240 min and 90 and 120 min for E. coli, S. aureus and L. monocytogenes, respectively. Radical-scavenging and antioxidant properties were tested by means of 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay and the β-carotene bleaching test. These properties were compared to those of Thymus x-porlock essential oil, used as a reference ingredient. The radical scavenging performance of the rosemary oil was better than that of C. cyminum. Results from the antioxidant test were better than those provided by the radical-scavenging activity. C. cyminum and R. officinalis essential oils may be considered as potent agents in food preservation.     

Study on chemical composition and biological activities of essential oil and extract from Salvia pisidica

In this study, total contents of phenolic, flavanol and flavonol, antioxidant activities and antimicrobial activities of the Turkish endemic Salvia pisidica Boiss. & Heldr. ex Bentham (Lamiaceae) extract and essential oil were assessed in vitro. Total phenolic, flavanol and flavonol contents in the extract were 54.57 mg gallic acid equivalents (GAE)/g, 16.70 mg catechine equivalents (CE)/g and 18.19 mg rutin equivalents (RE)/g, respectively. Antioxidant activities (IC₅₀ value) of the extract and essential oil were determined as 4.88 and 6.41 mg/mL by DPPH assay, respectively. 31 compounds were determined in the essential oil using GC-MS and the major compounds (%) were camphor (23.76), sabinol (19.2), α-thujone (14.2) and eucalyptol (1.8-cineole) (5.8).The antimicrobial activity of the methanolic extract and the essential oil against 13 bacterial and two yeast strains was determined. The extract (concentration 5 g/100 ml or 10 g/100 ml) was effective against most of the strains tested, yet not against Bacillus cereus, Staphylococcus aureus, Aeromonas hydrophila and the two yeast strains tested. The essential oil (2 g/100 ml) showed an antimicrobial effect against all the gram (+) bacteria tested, against Saccharomyces cerevisiae, but was not effective against all gram (−) bacteria and Candida albicans. These results show that S.piscidica essential oil and extract could be considered as a natural alternative to traditional food preservatives and be used to enhance food safety and shelf life.     

Chemical composition,antioxidant and antimicrobial activities of basil (Ocimum basilicum) essential oils depends on seasonal variations

Chemical composition, antioxidant and antimicrobial activities of the essential oils from aerial parts of basil (Ocimum basilicum L.) as affected by four seasonal, namely summer, autumn, winter and spring growing variation were investigated. The hydro-distilled essential oils content ranged from 0.5% to 0.8%, the maximum amounts were observed in winter while minimum in summer. The essential oils consisted of linalool as the most abundant component (56.7–60.6%), followed by epi-α-cadinol (8.6–11.4%), α-bergamotene (7.4–9.2%) and γ-cadinene (3.2–5.4%). Samples collected in winter were found to be richer in oxygenated monoterpenes (68.9%), while those of summer were higher in sesquiterpene hydrocarbons (24.3%). The contents of most of the chemical constituents varied significantly (p < 0.05) with different seasons. The essential oils investigated, exhibited good antioxidant activity as measurements by DPPH free radical-scavenging ability, bleaching β-carotene in linoleic acid system and inhibition of linoleic acid oxidation. Evaluation of antimicrobial activity of the essential oils and linalool, the most abundant component, against bacterial strains: Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pasteurella multocida and pathogenic fungi Aspergillus niger, Mucor mucedo, Fusarium solani, Botryodiplodia theobromae, Rhizopus solani was assessed by disc diffusion method and measurement of determination of minimum inhibitory concentration. The results of antimicrobial assays indicated that all the tested microorganisms were affected. Both the antioxidant and antimicrobial activities of the oils varied significantly (p < 0.05), as seasons changed.     

Antibacterial activity of the essential oils of Salvia officinalis L. and Salvia triloba L. cultivated in South Brazil

The essential oils of Salvia officinalis and Salvia triloba cultivated in South Brazil were analyzed by GC–MS. The major constituents of the oil of S. officinalis were α-thujone, 1,8-cineole, camphor, borneol and β-pinene, whereas those of S. triloba were α-thujone, 1,8-cineole, camphor, and β-caryophyllene. The essential oils of both species exhibited remarkable bacteriostatic and bactericidal activities against Bacillus cereus, Bacillus megatherium, Bacillus subtilis, Aeromonas hydrophila, Aeromonas sobria, and Klebsiella oxytoca. Moreover, the essential oil of S. triloba efficiently inhibited the growth of Staphylococcus aureus. S. aureus and A. hydrophila growth were drastically reduced even in the presence of 0.05 mg/ml of the essential oil of S. triloba.     

In vitro inhibitory effects of rosemary extracts on growth and glucosyltransferase activity of Streptococcus sobrinus

Rosemary (Rosmarinus officinalis L.) extract functions as an antioxidant and antimicrobial agent. In this study, we investigated in vitro effects of rosemary extracts on Streptococcus sobrinus growth and on its extracellular glucosyltransferase activity. The antibacterial activities of rosemary extracts were determined by the microdilution broth method. The minimum inhibitory concentrations of aqueous and methanolic rosemary extracts against S. sobrinus were 16 and 4 mg/ml, respectively. Glucosyltransferase activity was tested by incubating a crude enzyme preparation with sucrose and determining the amount of water-insoluble glucan formed. Both aqueous and methanolic extracts of rosemary markedly inhibited the formation of water-insoluble glucan. The 50% inhibitory doses of aqueous and methanolic extracts against the glucosyltransferases of S. sobrinus were 1.42 mg/ml and 0.34 mg/ml, respectively. Our results suggest that rosemary extract may prove effective for the inhibition of the growth of cariogenic oral streptococci.     

Antioxidant and antibacterial activities of Nephelium lappaceum L. extracts

Ether, methanolic and aqueous extracts of lyophilized rambutan (Nephelium lappaceum L.) peels and seeds were evaluated for phenolic contents, antioxidant and antibacterial activities. High amounts of phenolic compounds were found in the peel extracts and the highest content was in the methanolic fraction (542.2 mg/g dry extract). Several potential antioxidant activities, including reducing power, β-carotene bleaching, linoleic peroxidation and free radical scavenging activity, were evaluated. The peel extracts exhibited higher antioxidant activity than the seed extracts in all methods determined (P < 0.05). The methanolic fraction was found to be the most active antioxidant as shown by their 50% DPPH inhibition concentration, 4.94 μg/mL. The results indicated this fraction exhibited greater DPPH radical scavenging activity than BHT and ascorbic acid (0.32 g dry extract/g BHT or ascorbic acid). Antibacterial activity against eight bacterial strains was assessed by disc diffusion and broth macrodilution methods. All peel extracts exhibited antibacterial activity against five pathogenic bacteria. The most sensitive strain, Staphylococcus epidermidis, was inhibited by the methanolic extract (MIC 2.0 mg/mL).     

Antimicrobial activity of essential oil extracts of various onions (Allium cepa) and garlic (Allium sativum)

Antimicrobial activity of different concentrations (50, 100, 200, 300 and 500 ml/l) of essential oil extracts of three type of onions (green, yellow and red) and garlic against two bacteria, Staphylococcus aureus, Salmomella Enteritidis, and three fungi, Aspergillus niger, Penicillium cyclopium and Fusarium oxysporum, was investigated. The essential oil (EO) extracts of these Allium plants (garlic and onions) exhibited marked antibacterial activity, with garlic showing the highest inhibition and green onion the lowest. Comparatively, 50 and 100 ml/l concentrations of onions extracts were less inhibitory than 200, 300 and 500 ml/l concentrations. However, with garlic extract, high inhibitory activity was observed for all tested concentrations. S. aureus showed less sensitivity towards EO extracts inhibition, however S. Enteritidis was strongly inhibited by red onion and garlic extracts. The fungus F. oxysporum showed the lowest sensitivity towards EO extracts, whereas A. niger and P. cyclopium were significantly inhibited particularly at low concentrations. Conclusively, where seasoning is desired, essential oil extracts of onions and garlic can be used as natural antimicrobial additives for incorporating in various food products.     

Chemical composition and biological activities of Algerian Thymus oils

The compositions of essential oils isolated from nine samples of three Thymus species (Thymus algeriensis, Thymus pallescens and Thymus dréatensis) were analysed by GC and GC–MS, and a total of 114 components were identified. T. pallescens collected from various regions showed a great similarity in their compositions and were characterised by carvacrol (44.4–57.7%), p-cymene (10.3–17.3%) and γ-terpinene (10.8–14.2%) as the major components for four samples; only one sample was thymol-rich (49.3%) with a small amount of carvacrol (9.0%). On the other hand, T. algeriensis showed a chemical polymorphism, even for samples from the same location, and two new chemotypes for this species were proposed. Oxygen-containing monoterpenes were the predominant class (76.3%) in T. dreatensis oil, with linalool (30.4%), thymol (20.2%) and geraniol (19.6%) as the principal constituents. The oils were screened for their possible antioxidant activities by four complementary assays, namely DPPH free radical scavenging, hydroxyl radical scavenging, inhibition of lipid peroxidation and reducing power. The two new chemotypes of T. algeriensis exhibited strong hydroxyl radical scavenging (IC₅₀ = 2.2–3.3 μg/ml), but were not or only slightly active against the other radicals and exhibited a weak reducing power. Despite their chemical similarity, T. pallescens oils sometimes produced significant differences in their antioxidant activities. The essential oils were also screened for their antimicrobial activity against five bacteria (three Gram-positive and two Gram-negative) and one yeast (Candida albicans). The tested essential oils showed antimicrobial activity against the microorganisms used, in particular against two important pathogens, C. albicans and Helicobacter pylori.     

Phytochemical composition and in vitro antimicrobial and antioxidant activities of some medicinal plants

Different parts of three plants (Primula auriculata, Fumaria vaillantii and Falcaria vulgaris) were extracted with three different solvents to yield 72 crude extracts. The phytochemical analysis (chemical screening, GC–MS) of three plants was investigated for their antioxidant and antibacterial activity using nine Gram-positive and Gram-negative bacteria. The principal antioxidant and antimicrobial components were determined using HPLC with UV detection. All extracts possessed antibacterial activity especially methanolic extracts from flowers of P. auriculata. The DPPH-radical scavenging assay exhibited high antioxidant activities in three plants (more than 80% at 50 μg). The F. vulgaris showed high content of carvacrol (29.8%) as main component. The contents of carvacrol and fumaric acid in the methanolic–water extracts were 1119 and 1966 mg/l respectively. Our results indicate that these plants would be able to promise sources of natural products with potential antibacterial and antioxidant activity.     

Anthraquinone profile,antioxidant and antimicrobial activity of bark extracts of Rhamnus alaternus, R. fallax, R. intermedia and R. pumila

The quantity of phenols, as well as antioxidant and antimicrobial activities, were investigated in bark of Rhamnus alaternus L., R. fallax Boiss., R. intermedia Steud. et Hochst., and R. pumila Turra from natural stands in Croatia. The most abundant anthraquinones in the investigated extracts were chrysophanol in R. alaternus (3.14 mg/g), emodin in R. pumila (0.339 mg/g), and physcion in R. fallax (2.70 mg/g) and R. intermedia (0.285 mg/g). The species exhibiting the highest antioxidant activity were R. fallax and R. pumila. A positive correlation was observed between total phenolic and flavonoid levels of the extracts and antioxidant activity in some of the assays. All species showed antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Candida albicans, Aspergillus niger and Microsporum gypseum with minimal inhibitory concentrations equal to or below 2.500 mg/mL. The results indicate that the investigated Rhamnus species are a source of anthraquinones and other phenols, which act as multifunctional antioxidants with antimicrobial activity.     

Antibacterial activity of Thai edible plants against gastrointestinal pathogenic bacteria and isolation of a new broad spectrum antibacterial polyisoprenylated benzophenone,chamuangone

Twenty-two edible plant extracts were subjected to evaluation of their antibacterial activity against some gastrointestinal pathogenic bacteria, including Escherichiacoli, Salmonella typhimurium, Salmonella typhi, Shigella sonnei and Helicobacter pylori using the disc diffusion and broth microdilution methods. Sixteen of the plant extracts exhibited antibacterial activity against one or more tested bacteria. Only Garcinia cowa leaf extracts exhibited antibacterial activity against all tested bacteria. Purification of the ethyl acetate extract of G. cowa leaves using an antimicrobial assay-guided isolation afforded a new polyprenylated benzophenone, chamuangone, that exhibited satisfactory antibacterial activity against Streptococcus pyogenes (minimum inhibitory concentration (MIC) 7.8 μg/ml), Streptococcus viridans and H. pylori (MICs 15.6 μg/ml), and Staphylococcus aureus, Bacillus subtilis and Enterococcus sp. (MICs 31.2 μg/ml).     

Biodegradable gelatin–chitosan films incorporated with essential oils as antimicrobial agents for fish preservation

Essential oils of clove (Syzygium aromaticum L.), fennel (Foeniculum vulgare Miller), cypress (Cupressus sempervirens L.), lavender (Lavandula angustifolia), thyme (Thymus vulgaris L.), herb-of-the-cross (Verbena officinalis L.), pine (Pinus sylvestris) and rosemary (Rosmarinus officinalis) were tested for their antimicrobial activity on 18 genera of bacteria, which included some important food pathogen and spoilage bacteria. Clove essential oil showed the highest inhibitory effect, followed by rosemary and lavender. In an attempt to evaluate the usefulness of these essential oils as food preservatives, they were also tested on an extract made of fish, where clove and thyme essential oils were the most effective. Then, gelatin–chitosan-based edible films incorporated with clove essential oil were elaborated and their antimicrobial activity tested against six selected microorganisms: Pseudomonas fluorescens, Shewanella putrefaciens, Photobacterium phosphoreum, Listeria innocua, Escherichia coli and Lactobacillus acidophilus. The clove-containing films inhibited all these microorganisms irrespectively of the film matrix or type of microorganism. In a further experiment, when the complex gelatin–chitosan film incorporating clove essential oil was applied to fish during chilled storage, the growth of microorganisms was drastically reduced in gram-negative bacteria, especially enterobacteria, while lactic acid bacteria remained practically constant for much of the storage period. The effect on the microorganisms during this period was in accordance with biochemical indexes of quality, indicating the viability of these films for fish preservation.     

Essential oil composition,antimicrobial and antioxidant activities of Satureja cuneifolia Ten.

Satureja cuneifolia Ten. is a well-known aromatic plant which is frequently used as a spice and herbal tea in Anatolia. S. cuneifolia oil was analyzed by gas chromatography/mass spectrometry (GC/MS). The major components of S. cuneifolia oil were carvacrol (44.99%) and p-cymene (21.61%). The essential oil of S. cuneifolia exhibited antimicrobial activity against all of the tested foodborne and spoilage bacteria. The minimum inhibitory concentration (MIC) values for test bacteria which were sensitive to the essential oil of S. cuneifolia were in the range of 600–1400 μg/ml. Antioxidant activities of the essential oil and the methanolic extract from S. cuneifolia were evaluated by using DPPH radical scavenging, β-carotene–linoleic acid bleaching and metal chelating activity assays. In addition, the amounts of total phenol components in the plant methanolic extract (222.5 ± 0.5 μg/mg) and the oil (185.5 ± 0.5 μg/mg) were determined.     

Antibacterial activity of some Lamiaceae essential oils using resazurin as an indicator of cell growth

The aim of this work was to investigate the antibacterial activity of six Lamiaceae essential oils, against pathogenic and food spoilage bacteria. The chemical profiles of essential oils were evaluated by the means of GC and GC-MS. The major constituents of the oils were 1,8-cineol (29.2%), camphor (17.2%), α-pinene (11.5%) in Rosmarinus officinalis, citronellal (20.5%), β- geraniol (17.0%), β-citronellol (11.5%) in Melissa officinalis, 1,8-cineol (27.4%), α-thujone (16.3%), β-thujone (11.2%), borneol (10.4%), camphor (7.98%) in Salvia officinalis, linalool (25.1%), linalyl acetate (22.5%) in Lavandula angustifolia, thymol (52.4%), p-cymene (17.9%) in Thymus vulgaris and Patcholene alcohol (22.7%), α-bulnesene (17.1%), α-guaine (13.8%) in Pogostemon cablin. On quantitative basis, the amounts of 1,8-cineol, citronellal, 1,8-cineol, linalool, thymol and patchouli alcohol, calculated using calibrated curve with pure standard compounds, in the respective essential oils were found to be 28.4, 19.0, 26.7, 23.3, 51.1 and 21.1 g/100 g of oil, respectively. The modified resazurin microtitre-plate assay was used to evaluate the antibacterial activity of the essential oils and their principal components. All the essential oils analyzed presented inhibitory effects on most of the strains tested. Thymus vulgaris essential oil showed the highest inhibition. It was concluded that modified resazurin assay could be effectively used for reliable assessment of antibacterial activity of the tested essential oils against several Gram positive and negative bacterial taxa. The present results also demonstrated that Lamiaceae essential oils exhibiting higher antibacterial activity were generally rich in oxygenated monoterpens.     

Antimicrobial activity of some plant extracts and essential oils against foodborne pathogens in vitro and on the fate of inoculated pathogens in chocolate

The efficacy of commercially available plant extracts and essential oils used extensively as flavour ingredients in confectionery products were used as antimicrobials in laboratory media against the following microorganisms: Escherichia coli O157:H7, Salmonella Enteritidis, Salmonella Typhimurium, Staphylococcus aureus, Listeria monocytogenes, and Bacillus cereus. Using the disc diffusion method, inhibition zones in diameter >20 mm were observed by adding 10 μl of each antimicrobial substance on the following microorganisms: lemon flavour applied on E. coli O157:H7, lemongrass essences against S. aureus, plum using a B. cereus strain and strawberry flavour using a L. monocytogenes strain. E. coli O157:H7 strains were the most susceptible microorganisms inhibited by 18 extracts, followed by S. Typhimurium and S. aureus which were inhibited by 17 extracts. Lemon flavour, lemongrass essences, pineapple and strawberry flavour inhibited the foodborne pathogens at the lowest concentration (5 ml/100 ml). Plant extracts and essential oils with potent antimicrobial activities were tested in chocolate held at different temperatures (7 and 20 °C) in dry or humidified environment, which resulted in different a_w values of the product (i.e. 0.340, 0.450, and 0.822), in order to determine their efficacy on the fate of the inoculated pathogens. The most inhibitory action was observed by lemon flavour applied on chocolate inoculated with E. coli cocktail culture after storage at 20 °C for 9 days. Plant extracts tested on chocolate show an enhanced inhibitory effect during storage at 20 °C indicating that their application may provide protection in case of storage at the above temperature or even higher.     

Chemical composition and antioxidant and antimicrobial activity of two Satureja essential oils

Hydro-distilled volatile oils from the aerial parts of Satureja montana L., and Satureja subspicata Bartl. ex Vis., growing wild in Bosnia and Herzegovina, were analyzed by GC/MS. More than one hundred compounds were identified in both plant oils, representing 92.4–98.1% of the total oil. The major constituents of essential oils obtained from the plant material of S. montana, collected from two different localities, were thymol (31.7%), and geraniol (22.3%), respectively. The most abundant compounds in essential oils of S. subspicata, collected at two different stages of development, were thymol (28.6%), and spathulenol (37.6%), respectively. The screening of antimicrobial activity of essential oil samples was individually evaluated against Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa and Bacillus subtilis using a paper disc diffusion method. All tested microorganisms were inhibited by essential oil samples. Antioxidant activity was tested using the DPPH radical-scavenging method. All samples showed activity comparable to thymol, which was used as a positive probe.     

Chemical composition and antimicrobial properties of essential oils of three Australian Eucalyptus species

The chemical composition and antimicrobial properties of the essential oils of three common Australian Eucalyptus species, namely E. olida, E. staigeriana and E. dives were determined by gas chromatography/mass spectrometry and the agar disc diffusion method, respectively. A total of 24 compounds were identified from the essential oil of E. dives, with the dominant compounds being piperitone (40.5%), α-phellandrene (17.4%), p-cymene (8.5%) and terpin-4-ol (4.7%). For E. staigeriana, 29 compounds were identified with 1,8-cineole (34.8%), neral (10.8%), geranial (10.8%), α-phellandrene (8.8%) and methyl geranate (5.2%) being the dominant ones. In contrast, a single compound, (E)-methyl cinnamate, accounted for 99.4% of the essential oils of E. oilda, although 20 compounds were identified. The essential oils displayed a variable degree of antimicrobial activity with E. staigeriana oil showing the highest activity. In general, Gram-positive bacteria were found to be more sensitive to the essential oils than Gram-negative bacteria. Staphylococcus aureus was the most sensitive strain while Pseudomonas aeruginosa was the most resistant.     

Electrospray ionization mass spectrometry fingerprinting of essential oils: Spices from the Labiatae family

Polar components of the methanolic extracts of the essential oils of the spices Origanum dictamnus, Origanum vulgare, Origanum majorana and Rosmarinus officinalis, all four belonging to the Labiatae family, were investigated by direct infusion electrospray ionisation mass spectrometry (ESI-MS) both in the negative and positive ion modes. Characteristic ESI mass spectra with many diagnostic ions were obtained for the extracts of all four spices, serving for fast and reliable identification of these species. Tandem mass spectrometry (ESI-MS/MS), which often forms a series of fragment ions, and this additional MS dimension increases selectivity for authenticity and adulteration tests for spice essential oils. The MS technique also provides complementary information of component structures revealing the presence of important bioactive components.     

Chlorogenic acids and related compounds in medicinal plants and infusions

The consumption of plant infusions for prevention and treatment of health disorders is a worldwide practise. Various pharmacological activities inherent to medicinal plants have been attributed to their phenolic composition, including chlorogenic acids (CGA). Studies have shown potential beneficial properties of CGA to humans such as antioxidant, hepatoprotective, hypoglycaemic. In the present study, the CGA composition of 14 dried medicinal plants was determined by HPLC-UV and LC-DAD–ESI-MS. The plants with the highest CGA contents were Ilex paraguariensis, Bacharis genistelloides, Pimpinella anisum, Achyrochine satureioides, Camellia sinensis, Melissa officinalis and Cymbopogon citratus, with 84.7 mg/100 g–9.7 g/100 g, dry weight. Plant infusions were prepared (at 0.5%) in order to evaluate the actual consumption of CGA through these beverages. Total CGA contents in the infusions were similar to those in the methanolic extracts and indicated that a satisfactory extraction occurs during the preparation of infusions. These CGA-rich plants deserve attention regarding the pharmacological properties attributed to CGA.     

In vitro and in vivo antifungal activities of the essential oils of various plants against tomato grey mould disease agent Botrytis cinerea

The aim of this study was to find an alternative to synthetic fungicides currently used in the control of devastating fungal pathogen Botrytis cinerea, the causal agent of grey mould disease of tomato. Antifungal activities of essential oils obtained from aerial parts of aromatic plants, which belong to the Lamiacea family such as origanum (Origanum syriacum L. var. bevanii), lavender (Lavandula stoechas L. var. stoechas) and rosemary (Rosmarinus officinalis L.), were investigated against B. cinerea. Contact and volatile phase effects of different concentrations of the essential oils were found to inhibit the growth of B. cinerea in a dose-dependent manner. Volatile phase effects of essential oils were consistently found to be more effective on fungal growth than contact phase effect. A volatile vapour of origanum oil at 0.2 μg/ml air was found to completely inhibit the growth of B. cinerea. Complete growth inhibition of pathogen by essential oil of lavender and rosemary was, however, observed at 1.6 μg/ml air concentrations. For the determination of the contact phase effects of the tested essential oils, origanum oil at 12.8 μg/ml was found to inhibit the growth of B. cinerea completely. Essential oils of rosemary and lavender were inhibitory at relatively higher concentrations (25.6 μg/ml). Spore germination and germ tube elongation were also inhibited by the essential oils tested. Light and scanning electron microscopic (SEM) observations revealed that the essential oils cause considerable morphological degenerations of the fungal hyphae such as cytoplasmic coagulation, vacuolations, hyphal shrivelling and protoplast leakage and loss of conidiation. In vivo assays with the origanum essential oil, being the most efficient essential oil, under greenhouse conditions using susceptible tomato plants resulted in good protection against grey mould severity especially as a curative treatment. This study has demonstrated that the essential oils are potential and promising antifungal agents which could be used as biofungicide in the protection of tomato against B. cinerea.