Inhibitory effects of selected plant essential oils on the growth of four pathogenic bacteria: E. coli O157:H7, Salmonella Typhimurium, Staphylococcus aureus and Listeria monocytogenes

Survival of spoilage bacteria subjected to sequential eugenol and temperature treatments

Effects of a sequential application of eugenol and temperature on the survival of two model spoilage organisms, Staphylococcus carnosus LTH1502 and Escherichia coli K12 C600, were studied. To assess effects of a "temperature first-antimicrobial later" treatment, cultures were treated with eugenol at 20, 37 and 42 °C at the beginning of the incubation period, and after 3h and 8h. To assess effects of an "antimicrobial first-temperature later" treatment, eugenol was added at the beginning of the incubation period at 37 °C and temperature was changed to 20 or 42 °C after 3 or 8h. Cell numbers were determined in regular intervals during the incubation period using plate counts. Partitioning of eugenol was measured by HPLC, and cell morphology was assessed by electron microscopy. Combined treatments were more effective against the Gram negative E. coli than against S. carnosus. Order of application influenced the effectiveness of treatments, especially at 42 °C. There, the temperature first-eugenol later treatment was less effective than other treatments, likely due to temperature-induced adaptation processes occurring in cellular membranes making them more resistant against a later eugenol treatment. Results are of significance in situations where combinations of sublethal stresses are used to build a hurdle concept for food preservation.

Possible Synergistic Effects of Thymol and Nicotine Against Crithidia bombi Parasitism in Bumble Bees

Floral nectar contains secondary compounds with antimicrobial properties that can affect not only plant-pollinator interactions, but also interactions between pollinators and their parasites. Although recent work has shown that consumption of plant secondary compounds can reduce pollinator parasite loads, little is known about the effects of dosage or compound combinations. We used the generalist pollinator Bombus impatiens and its obligate gut parasite Crithidia bombi to study the effects of nectar chemistry on host-parasite interactions. In two experiments we tested (1) whether the secondary compounds thymol and nicotine act synergistically to reduce parasitism, and (2) whether dietary thymol concentration affects parasite resistance. In both experiments, uninfected Bombus impatiens were inoculated with Crithidia and then fed particular diet treatments for 7 days, after which infection levels were assessed. In the synergism experiment, thymol and nicotine alone and in combination did not significantly affect parasite load or host mortality. However, the thymol-nicotine combination treatment reduced log-transformed parasite counts by 30% relative to the control group (P = 0.08). For the experiment in which we manipulated thymol concentration, we found no significant effect of any thymol concentration on Crithidia load, but moderate (2 ppm) thymol concentrations incurred a near-significant increase in mortality (P = 0.054). Our results tentatively suggest the value of a mixed diet for host immunity, yet contrast with research on the antimicrobial activity of dietary thymol and nicotine in vertebrate and other invertebrate systems. We suggest that future research evaluate genetic variation in Crithidia virulence, multi-strain competition, and Crithidia interactions with the gut microbe community that may mediate antimicrobial activities of secondary compounds.

Chemical composition and evaluation of the antimicrobial activity of the essential oil from leaves of Eugenia platysema

This study describes the qualitative and quantitative chemical composition and evaluates the antibacterial activity of essential oil from Eugenia platysema leaves. Analysis by GC-FID and GC-MS allowed the identification of 22 compounds. Different from the other species of the Eugenia genus, the major compound found in the essential oil was the diterpene phytol (66.05%), being this the first report of the presence of this compound in the essential oils from Eugenia genus. The sesquiterpene elixene was the second most concentrated compound in the studied essential oil (9.16%). The essential oil from E. platysema was tested for its antibacterial activity against cell-walled bacteria and mollicute strains of clinical interest using the microdilution broth assay. The results showed that the essential oil of E. platysema was inactive until 1000 μg mL(-1) against tested bacteria.

Probiotic Characteristics of Lactobacillus plantarum FH185 Isolated from Human Feces

Lactobacillus plantarum FH185 was isolated from the feces of healthy adults. In our previous study, L. plantarum FH185 was demonstrated that it has anti-obesity effect in the in vitro and in vivo test. In order to determine its potential for use as a probiotic, we investigated the physiological characteristics of L. plantarum FH185. The optimum growth temperature of L. plantarum FH185 was 40℃. L. plantarum FH185 showed higher sensitivity to novobiocin in a comparison of fifteen different antibiotics and showed higher resistance to polymyxin B and vancomycin. It also showed higher β-galactosidase and N-acetyl-β-glucosaminidase activities. Moreover, it was comparatively tolerant to bile juice and acid, and inhibited the growths of Salmonella Typhimurium and Staphylococcus aureus with rates of 44.76% and 53.88%, respectively. It also showed high adhesion activity to HT-29 cells compared to L. rhamnosus GG.

Synergism between carvacrol or thymol increases the antimicrobial efficacy of soy sauce with no sensory impact

Here, we examined the antimicrobial effects of soy sauce containing essential oils (EOs) against Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes at 22°C and 4°C. To screen a variety of combined effects, soy sauce was mixed with six different EOs (carvacrol, thymol, eugenol, trans-cinnamaldehyde, β-resorcylic acid, and vanillin), each at a concentration of 1mM for 10 min. None of the oils showed bactericidal activity when used alone. Soy sauce combined with carvacrol and thymol induced the greatest antibacterial activity against all tested bacteria; therefore, these oils were further tested at 0.25, 0.5, and 1mM (0.0039%, 0.0078%, and 0.0157%) for 1, 5, and 10 min at 4°C and 22°C. In addition, sensory evaluation of soy sauce containing each EO at 0.25, 0.5, 1, and 2mM was performed using the nine point hedonic test. Carvacrol or thymol (1mM) eliminated all the test bacteria (initial population, 7.0-7.5logCFU/ml) in 1-5 min at 22°C and within 10 min at 4°C. L. monocytogenes was slightly more tolerant at 4°C, which may be attributable to the ability of the cell membrane to adapt to low temperatures. The sensory scores for soy sauce containing EOs were not significantly different from that of soy sauce without EOs (P>0.05). The stability of EO efficacy in soy sauce was also verified. These results suggest that carvacrol and thymol act synergistically with other factors present in soy sauce to increase antimicrobial activity against major foodborne pathogens at both 4°C and 22°C. The synergism may be attributable to the combination of factors (mainly high salt concentration and low pH imparted by organic acids) present in soy sauce and the membrane attacking properties of carvacrol and thymol. This method will facilitate the production of microbiologically safe soy sauce, soy sauce-based marinades, and various marinated foods.

Macrocarpal-like Compounds from Eugenia umbelliflora Fruits and Their Antibacterial Activity

Certain members of the genus Eugenia are used as foods. One of these species is Eugenia umbelliflora, which is used for its fruits. The aim of the study was to isolate the constituents of the CH2Cl2 fraction obtained from E. umbelliflora O. Berg (Myrtaceae) and also to evaluate its antimicrobial properties. Two new meroterpenoids, eugenial C (3) and eugenial D (4) were isolated from the unripe fruits of E. umbelliflora and their structures established mainly by extensive NMR spectroscopy. In previous studies, the CH2Cl2 extract showed significant antibacterial activity, which can be attributed to meroterpenoids isolated in this study. The compounds eugenials C and D exhibited potent activity against Bacillus subtilis and Staphylococcus aureus and different strains of MRSA and activity similar to those of the antibiotics used in antimicrobial therapies.

Potential of Plant Essential Oils and Their Components in Animal Agriculture - in vitro Studies on Antibacterial Mode of Action

The antimicrobial activity of essential oils and their components has been recognized for several years. Essential oils are produced as secondary metabolites by many plants and can be distilled from all different portions of plants. The recent emergence of bacteria resistant to multiple antibiotics has spurred research into the use of essential oils as alternatives. Recent research has demonstrated that many of these essential oils have beneficial effects for livestock, including reduction of foodborne pathogens in these animals. Numerous studies have been made into the mode of action of essential oils, and the resulting elucidation of bacterial cell targets has contributed to new perspectives on countering antimicrobial resistance and pathogenicity of these bacteria. In this review, an overview of the current knowledge about the antibacterial mode of action of essential oils and their constituents is provided.

Influence of extraction methods on antioxidant and antimicrobial properties of essential oil from Thymua danesis subsp. Lancifolius

The essential oil (EO) from dried ground powder leaves and stems of Thymua danesis was extracted using hydrodistillation (HD), ohmic extraction (OE), ultrasound‐assisted HD and ultrasound‐assisted OE methods. Then, the antioxidant, antimicrobial, and sensory properties of the EO were investigated both in vitro and in food systems. Thyme EO extracted by ultrasound‐assisted HD method had promising antibacterial activities against Escherichia coli and Staphylococcus aureus and had the best antioxidant properties when tested in vitro. In food systems, higher concentrations of the EO were needed to exert similar antibacterial and antioxidant effects. Furthermore, thyme EO added yogurt and drink yogurt revealed better sensory properties than the control and fresh samples. Essential oil from Thymua danesis has a good potential to be used as an antioxidant, antimicrobial, and flavoring agent in food systems and the extraction method effects on the antioxidant and antimicrobial properties of the thyme extract.

Antibacterial activity and mode of action of selected glucosinolate hydrolysis products against bacterial pathogens

Plants contain numerous components that are important sources of new bioactive molecules with antimicrobial properties. Isothiocyanates (ITCs) are plant secondary metabolites found in cruciferous vegetables that are arising as promising antimicrobial agents in food industry. The aim of this study was to assess the antibacterial activity of two isothiocyanates (ITCs), allylisothiocyanate (AITC) and 2-phenylethylisothiocyanate (PEITC) against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Listeria monocytogenes. The antibacterial mode of action was also characterized by the assessment of different physiological indices: membrane integrity, intracellular potassium release, physicochemical surface properties and surface charge. The minimum inhibitory concentration (MIC) of AITC and PEITC was 100 μg/mL for all bacteria. The minimum bactericidal concentration (MBC) of the ITCs was at least 10 times higher than the MIC. Both AITC and PEITC changed the membrane properties of the bacteria decreasing their surface charge and compromising the integrity of the cytoplasmatic membrane with consequent potassium leakage and propidium iodide uptake. The surface hydrophobicity was also non-specifically altered (E. coli and L. monocytogenes become less hydrophilic; P. aeruginosa and S. aureus become more hydrophilic). This study shows that AITC and PEITC have strong antimicrobial potential against the bacteria tested, through the disruption of the bacterial cell membranes. Moreover, phytochemicals are highlighted as a valuable sustainable source of new bioactive products.

Chemical Profile, Antibacterial and Antioxidant Activity of Algerian Citrus Essential Oils and Their Application in Sardina pilchardus

Stored fish are frequently contaminated by foodborne pathogens. Lipid oxidation and microbial growth during storage are also important factors in the shelf-life of fresh fish. In order to ensure the safety of fish items, there is a need for control measures which are effective through natural inhibitory antimicrobials. It is also necessary to determine the efficacy of these products for fish protection against oxidative damage, to avoid deleterious changes and loss of commercial and nutritional value. Some synthetic chemicals used as preservatives have been reported to cause harmful effects to the environment and the consumers. The present investigation reports on the extraction by hydrodistillation and the chemical composition of three citrus peel essential oils (EOs): orange (Citrus sinensis L.), lemon (Citrus limonum L.) and bergamot (Citrus aurantium L.) from Algeria. Yields for EOs were between 0.50% and 0.70%. The chemical composition of these EOs was determined by gas chromatography coupled with mass spectrometry (GC/MS). The results showed that the studied oils are made up mainly of limonene (77.37%) for orange essential oil (EO); linalyl acetate (37.28%), linalool (23.36%), for bergamot EO; and finally limonene (51.39%), β-pinene (17.04%) and γ-terpinene (13.46%) for lemon EO. The in vitro antimicrobial activity of the EOs was evaluated against Staphylococcus aureus (S. aureus) using the agar diffusion technique. Results revealed that lemon EO had more antibacterial effects than that from other EOs. Minimal inhibitory concentrations (MICs) showed a range of 0.25–0.40 μL/mL. Lemon and bergamot citrus peel EOs were added at 1 × MIC and 4 × MIC values to Sardina pilchardus (S. pilchardus) experimentally inoculated with S. aureus at a level of 3.5 log₁₀ CFU/g and stored at 8 ± 1 °C. The results obtained revealed that the 4 × MIC value of bergamot reduced completely the growth of S. aureus from day 2 until the end of storage. The presence of EOs significantly extended lipid stability. Samples treated with bergamot EO displayed greater antioxidant activity than lemon EO. In fact, the oxidation rate is inversely proportional to the concentration of EO. At 1 × MIC and 4 × MIC values of bergamot EO, the levels of malonaldehyde compared to the control samples were 1.66 and 1.28 mg malonaldehyde/kg at the end of storage, corresponding to inhibition percentages of 42.76% and 55.87%, respectively. These results suggest the possibility that citrus EOs could be used as a way of combating the growth of common causes of food poisoning and used as potent natural preservatives to contribute to the reduction of lipid oxidation in sardines.

Antimicrobial Effects of Nisin, Essential Oil, and γ-Irradiation Treatments against High Load of Salmonella typhimurium on Mini-carrots

This study aimed at using essential oil (EO) alone or combined EO with nisin and γ-irradiation to control Salmonella Typhimurium during the refrigerated storage of mini-carrots. Peeled mini-carrots were inoculated with S. Typhimurium at a final concentration of approximately 7 log CFU/g. Inoculated samples were coated by 5 different coating solutions: (i) nisin solution at final concentration of 10(3) IU/mL; (ii) mountain savory EO solution at 0.35%; (iii) carvacrol solution at 0.35%; (iv) mountain savory EO at 0.35% plus nisin solution of 10(3) IU/mL; or (v) carvacrol at 0.35% plus nisin solution of 10(3) IU/mL. Coated mini-carrots were then irradiated at 0.5 or 1.0 kGy and compared to an unirradiated control sample. Samples were kept at 4 °C and microbial analyses were conducted at days 1, 3, 6, and 9. The results showed that mini-carrots coated by carvacrol plus nisin solution or mountain savory EO plus nisin solution in combination with irradiation at 1.0 kGy completely eliminated S. Typhimurium to under the detection limit during the storage. Thus, the combined treatments using carvacrol plus nisin or mountain savory EO plus nisin coating solution and irradiation at 1.0 kGy could be used as an effective method for controlling S. Typhimurium in mini-carrots.

PRACTICAL APPLICATION

This study shows the effect of using γ irradiation at low dose (1 kGy) to reduce significantly the growth of Salmonella typhimurium in mini-carrots. It also shows that combination of nisin, essential oils with γ irradiation have the best antibacterial effects against S. Typhimurium during the storage of mini-carrots. The results can be used for practical application in food industry in terms of food safety.

A pharmacological and phytochemical overview on Satureja

CONTEXT

Satureja (Lamiaceae) species are used as flavoring compounds in food, pharmaceutical, and cosmetic industries because of its sweetness and simple cultivation characteristics. They have traditionally been used as muscle pain relievers, tonic, and carminative agents to treat stomach and intestinal disorders such as cramps, nausea, indigestion, and diarrhea, due to their considerable phytochemical characteristics.

OBJECTIVE

This review evaluates some information published since 1989 on Satureja genus from a systematic perspective in terms of its pharmacological and phytochemical characteristics.

MATERIALS AND METHODS

Web of Science, PubMed, Scopus, and Google Scholar databases were searched up to March 2014. "Satureja" was used as a research term without narrowing or limiting research elements. After obtaining all reports from database (a total number is about 637), the papers were carefully analyzed in order to find data related to the topic of this review.

RESULTS

In this review, 453 reports were used which were published between 1989 and 2014. The study was compiled into two sections (Pharmacology and Phytochemistry). In the pharmacology section, more than 50 different activities were studied. In the second section, in addition to other compounds and inorganic substances, volatiles, phenolic acids, and flavonoids were discussed.

DISCUSSION AND CONCLUSION

According to our contemporary information, Satureja species have been evaluated for their wide range of biological activities. However, a small part of these studies have been carried out on the active principles. Therefore, in the future, more studies should be carried out to identify responsible phytochemicals for the various activities.

Survival of Salmonella and Escherichia coli O157:H7 on strawberries, basil, and other leafy greens during storage

The survival of Salmonella and Escherichia coli O157:H7 on strawberries, basil leaves, and other leafy greens (spinach leaves, lamb and butterhead lettuce leaves, baby leaves, and fresh-cut iceberg lettuce) was assessed at cold (<7 °C) and ambient temperatures. All commodities were spot inoculated with E. coli O157:H7 or Salmonella to obtain an initial inoculum of 5 to 6 log and 4 to 5 log CFU/g for strawberries and leafy greens, respectively. Samples were air packed. Strawberries were stored at 4, 10, 15, and 22 °C and basil leaves and other leafy greens at 7, 15, and 22 °C for up to 7 days (or less if spoiled before). Both Salmonella and E. coli O157:H7 showed a gradual decrease in numbers if inoculated on strawberries, with a similar reduction observed at 4, 10, and 15 °C (2 to 3 log after 5 days). However, at 15 °C (and 10 °C for E. coli O157:H7), the survival experiment stopped before day 7, as die-off of both pathogens below the lower limit of detection was achieved or spoilage occurred. At 22 °C, strawberries were moldy after 2 or 4 days. At that time, a 1- to 2-log reduction of both pathogens had occurred. A restricted die-off (on average 1.0 log) and increase (on average , 0.5 log) of both pathogens on basil leaves occurred after 7 days of storage at 7 and 22 °C, respectively. On leafy greens, a comparable decrease as on basil was observed after 3 days at 7 °C. At 22 °C, both pathogens increased to higher numbers on fresh-cut iceberg and butterhead lettuce leaves (on average 1.0 log), probably due to the presence of exudates. However, by using spot inoculation, the increase was rather limited, probably due to minimized contact between the inoculum and cell exudates. Avoiding contamination, in particular, at cultivation (and harvest or postharvest) is important, as both pathogens survive during storage, and strawberries, basil, and other leafy green leaves are consumed without inactivation treatment.

Synergy among thymol, eugenol, berberine, cinnamaldehyde and streptomycin against planktonic and biofilm-associated food-borne pathogens

Essential oils have been found to exert antibacterial, antifungal, spasmolytic, and antiplasmodial activity and therapeutic effect in cancer treatment. In this study, the antibacterial activities of four main essential oils' components (thymol (Thy), eugenol (Eug), berberine (Ber), and cinnamaldehyde (Cin)) were evaluated against two food-borne pathogens, Listeria monocytogenes and Salmonella Typhimurium, either alone or in combination with streptomycin. Checkerboard assay demonstrated that Thy and Cin elicited a synergistic effect with streptomycin against L. monocytogenes, while a synergy existed between Cin or Eug and streptomycin against Salm. Typhimurium. Further experiments showed that this synergy was sufficient to eradicate biofilms formed by these two bacteria. Thus, our data highlighted that the combinations of specific components from essential oils and streptomycin were useful for the treatment of food-borne pathogens, which might help prevent the spread of antibiotic resistance through improving antibiotic effectiveness.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study has shown the synergistic effect of four components of essential oil (thymol, eugenol, berberine and cinnamaldehyde) combined with streptomycin on planktonic and biofilm-associated food-borne pathogens Listeria monocytogenes and Salmonella Typhimurium. These findings indicate that combination of specific components of essential oils with streptomycin may provide alternative methods to overcome the problem of food-borne bacteria both in suspension and in biofilm.

Evaluation of usage of essential oils instead of spices in meat ball formulation for controlling Salmonella spp

The purpose of this study was to show the efficacy of essential oils (EOs) in meat balls instead of spices because of their high antimicrobial effect and to evaluate the antimicrobial effect of Origanum onites and Ocimum basilicum EOs against Salmonella Typhimurium in minced beef (20% fat) stored at 4 ℃ for seven days. This is the first study about use of O. basilicum EO in minced beef against bacterial pathogens. Both EOs inhibit microorganisms in in vitro antibacterial tests. Minimum inhibitory concentration (MIC) values of EOs were determined. The lowest MIC values were obtained with O. onites EO 0.6 µl/ml against S. Typhimurium strains. The MIC values of O. basilicum EO 0.25 µl/ml against microorganisms. Both EOs showed a significant decrease in microorganisms inoculated in minced beef at end of storage. The concentration of the both EOs at 20 µg/mg and 10 µg/mg showed stronger antimicrobial activity against bacterial cocktail of S. Typhimurium in beef; however, the higher concentrations caused alterations in the organoleptic properties of meatballs. The results of the present study indicate that O. onites and O. basilicum EOs may be used in combination with each other and different food preservation systems in meat ball formulation.

Efficiency of vanilla, patchouli and ylang ylang essential oils stabilized by iron oxide@C14 nanostructures against bacterial adherence and biofilms formed by Staphylococcus aureus and Klebsiella pneumoniae clinical strains

Biofilms formed by bacterial cells are associated with drastically enhanced resistance against most antimicrobial agents, contributing to the persistence and chronicization of the microbial infections and to therapy failure. The purpose of this study was to combine the unique properties of magnetic nanoparticles with the antimicrobial activity of three essential oils to obtain novel nanobiosystems that could be used as coatings for catheter pieces with an improved resistance to Staphylococcus aureus and Klebsiella pneumoniae clinical strains adherence and biofilm development. The essential oils of ylang ylang, patchouli and vanilla were stabilized by the interaction with iron oxide@C₁₄ nanoparticles to be further used as coating agents for medical surfaces. Iron oxide@C₁₄ was prepared by co-precipitation of Fe⁺² and Fe⁺³ and myristic acid (C₁₄) in basic medium. Vanilla essential oil loaded nanoparticles pelliculised on the catheter samples surface strongly inhibited both the initial adherence of S. aureus cells (quantified at 24 h) and the development of the mature biofilm quantified at 48 h. Patchouli and ylang-ylang essential oils inhibited mostly the initial adherence phase of S. aureus biofilm development. In the case of K. pneumoniae, all tested nanosystems exhibited similar efficiency, being active mostly against the adherence K. pneumoniae cells to the tested catheter specimens. The new nanobiosystems based on vanilla, patchouli and ylang-ylang essential oils could be of a great interest for the biomedical field, opening new directions for the design of film-coated surfaces with anti-adherence and anti-biofilm properties.

Plants belonging to the genus Thymus as antibacterial agents: from farm to pharmacy

In traditional medicine, plants have been used since ancient times for the prevention and/or protection against infectious diseases. In recent years, the use of herbal medicines and food supplements containing botanical ingredients, as alternative therapy for infectious diseases, has been intensified due to their high content of antimicrobial agents such as polyphenols, i.e. flavonoids, tannins, and alkaloids. Plants from the genus Thymus are important medicinal herbs, which are known to contain antimicrobial agents, and are rich in different active substances such as thymol, carvacrol, p-cymene and terpinene. In this review, we summarise the available literature data about the in vitro antibacterial effects of the main plants belonging to the genus Thymus. We also provide information about cultivation, chemical composition of the essential oils obtained from these plants, and their use for medicinal purposes.

Rhamnolipids as emulsifying agents for essential oil formulations: antimicrobial effect against Candida albicans and methicillin-resistant Staphylococcus aureus

This work examines the influence of essential oil composition on emulsification with rhamnolipids and their use as therapeutic antimicrobial agents against two opportunistic pathogens, methicillin-resistant Staphylococcus aureus (MRSA) and Candida albicans. Rhamnolipids, produced by Pseudomonas aeruginosa, with waste frying oil as the carbon source, were composed of eight rhamnolipid homologues. The rhamnolipid mixture was used to produce emulsions containing essential oils (EOs) of Melaleuca alternifolia, Cinnamomum verum, Origanum compactum and Lavandula angustifolia using the titration method. Ternary phase diagrams were designed to evaluate emulsion stability, which differed depending on the essential oil. The in vitro antimicrobial activity of the EOs alone and the emulsions was evaluated. The antimicrobial activity presented by the essential oils alone increased with emulsification. The surface properties of rhamnolipids contribute to the positive dispersion of EOs and thus increase their availability and antimicrobial activity against C. albicans and S. aureus. Therefore, rhamnolipid-based emulsions represent a promising approach to the development of EO delivery systems.

Antimicrobial and mechanical properties of β-cyclodextrin inclusion with essential oils in chitosan films

Chitosan films incorporated with various concentrations of the complex of β-cyclodextrin and essential oils (β-CD/EO) were prepared and investigated for antimicrobial, mechanical, and physical properties. Four bacterial strains that commonly contaminate food products were chosen as target bacteria to evaluate the antimicrobial activity of the prepared films. The incorporation of β-CD/EO significantly increased the antimicrobial activities of the chitosan films against Escherichia coli, Salmonella typhimurium, Staphylococcus aureus, and Listeria monocytogenes. It was also found that tensile strength (TS) of chitosan film was significantly increased with the incorporation of the β-cyclodextrin and 0.75% essential oils complex. The elongation at break (EB) decreased with the increasing concentrations of essential oils. Inclusion of the complex of β-cyclodextrin and 0.25% essential oils also significantly decreased water vapor permeability (WVP) of chitosan films. Our results suggest that chitosan films containing β-CD/EO could be used as active food-packaging material.