Academic literature on the topic 'Oregano essential oil (OEO)'

Purpose – This paper aimed to evaluate sensory acceptability of salad dressing formulated with different quantities of oregano essential oil (OEO) and salt as a starting point for the use of the spice as a natural preservative in food. Design/methodology/approach – Sensory assessment of salad dressing with OEO was evaluated in relation to the following attributes: appearance, aroma, consistence, flavour and overall acceptability. Five formulations were developed with variation in the levels of OEO and sodium chloride through a 22 factorial design with a central point. A nine-point hedonic scale was used, besides purchase intent by a structured five-point scale. Findings – There was no significant difference in the acceptance of the samples. Cluster analysis showed that formulation with intermediate quantities of salt and OEO was preferred by the consumers. OEO salad dressings with low salt content, regardless of OEO amount, presented higher intention to purchase. Research limitations/implications – Due to an increasing interest in the use of natural preservatives to replace chemical additives, this study provided a starting point for further investigations concerning sensory acceptability of OEO in food. Practical implications – Finding the balance between pleasant flavour and significant reduction of the use of salt in foods for dietary reasons is a complex challenge. Furthermore, studies need to be performed concerning interaction between amounts of essential oils and salt. Originality/value – This study provides insights that suggest a promising usage of OEO in food.

Oregano is widely used as aromatics in food and alcohol. Oregano oil has been used in traditional medicine for decades. Oregano essential oil (OEO) is extracted from leaves from the oregano plant. Oregano is known for its antibacterial and antispasmodic properties due to its polyphenol content, which includes many flavones. The aim of the study was to assess the Anti-Inflammatory Potential of Intracanal Medicament Containing Oregano Essential Oil (OEO). The anti-inflammatory activity of an intracanal medicament containing oregano essential oil at various concentrations was evaluated using the raw 264.7 cell line. The ability of extracts to suppress nitric oxide generation by cells was used to calculate percentage inhibition. Curcumin was used as the standard. The study concluded that anti-inflammatory activity of the formulation showed IC50 value of 94.34%, and hence can be used clinically to treat infected root canals.

The preservative effect of the addition of different essential oils (copaiba and oregano) on meat quality parameters and sensorial acceptability was analyzed for fresh ground beef patties over 21 days of display. Five treatments were assessed: control (CON) without antioxidants; addition of the synthetic additive butylated hydroxytoluene (BHT); addition 0.05% of copaiba essential oil (CEO); 0.05% of oregano essential oil (OEO); or blend of 0.025% copaiba and 0.025% oregano essential oils (BEO). The lowest cooking losses and greatest tenderness (P <0.05) were reached with the blend (BEO). The inclusion of oregano essential oil presented a more intense chroma (P <0.05), with the best color retained during display. Oregano essential oil (OEO) and the blend (BEO) showed the highest antioxidant activity, reducing the lipid oxidation of beef patties during display (P < 0.05). Consumers preferred the odor of beef patties with essential oils (OEO and BEO) to the CON; however, the flavor from OEO had the lowest acceptability and the worst scores for overall acceptability (P < 0.05). Patties with the blend addition (BEO) were the best scored on overall acceptability assessments. In conclusion, the oregano and copaiba essential oils blend had a good preservative effect on fresh beef patties during display and increased sensory acceptability of the product, thus being a possible alternative for replacing synthetic compounds in processed foods.

The present study aimed to develop biodegradable starch films with starch nanoparticles incorporated with oregano essential oil – OEO (Origanum vulgare), for application as active packaging in food preservation. Film production was performed using the casting method. Three concentrations of oregano essential oil (0.0%, 5.0% and 10%) were studied. The physical and mechanical properties of the films produced were also evaluated. For analysis of antimicrobial efficiency, the methodologies of CLSI and APHA were used. The incorporation of essential oregano oil influenced the performance of the films. The films with 5.0% and 10% OEO showed antimicrobial efficiency when compared to the control.

ABSTRACT In this study, the effectiveness of pullulan (a fungal polysaccharide) film containing oregano essential oil (OEO) at 1.0 to 10.0% was evaluated against bacteria, yeasts, and molds. The quality of the sprouts, as determined by weight loss, color, and appearance, was monitored during storage at 2 and 16°C. An organoleptic evaluation of odor preference and odor acceptability of OEO on the Brussels sprouts was also conducted. The antimicrobial activity of pullulan films with OEO increased significantly with the increase in OEO concentration (1 to 10%). Pullulan films with OEO were more effective for inhibiting the growth of yeasts and molds than for inhibiting gram-positive and gram-negative bacteria. Pullulan with 1.0% OEO was an effective combination and was used subsequently as the base coating for maintaining the safety and quality of fresh Brussels sprouts stored at 16°C for 14 days. The pullulan coating containing 1.0% OEO reduced Aspergillus niger populations by 2 log CFU/g. This coating also reduced weight loss in the sprouts. Compared with uncoated Brussels sprouts, the percent weight loss after 14 days was reduced in samples coated with pullulan and with pullulan plus 1% OEO by 3.81 and 6.06%, respectively, after storage at 2°C and by 8.04 and 9.30%, respectively, after storage 16°C. The coating also significantly reduced changes in general appearance and color during storage. Evaluation of the organoleptic properties indicated that pullulan containing OEO had only a slight detrimental effect on odor properties. Incorporating OEO into a delivery system for antimicrobial compounds in pullulan coatings extended the microbiological shelf life of Brussels sprouts.

Oregano essential oil (OEO) is an effective natural antibacterial agent, but its antibacterial activity against Vibrio vulnificus has not been widely studied. The aim of this study was to investigate the inhibitory effect and germicidal activity of OEO on V. vulnificus and its possible inhibition mechanism. The minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of OEO against four V. vulnificus strains (ATCC 27562 and three isolates from seafoods) were from 0.06 to 0.15 μL/mL. Compared with untreated bacteria, OEO reduced the concentration of intracellular adenosine triphosphate (ATP), hyperpolarized the cell membrane, increased the level of reactive oxygen species (ROS), and increased the concentration of intracellular malondialdehyde (MDA), but there was no obvious DNA damage at the OEO test concentration. It was indicated that OEO inactivated V. vulnificus by generating ROS which caused lipid peroxidation of cell membranes, thereby reducing the permeability and integrity of cell membranes and causing morphological changes to cells, but there was no obvious damage to DNA. In addition, OEO could effectively kill V. vulnificus in oysters at 25 °C, and the number of bacteria decreased by 48.2% after 0.09% OEO treatment for 10 h. The good inhibitory effect and bactericidal activity of OEO showed in this study, and the economy and security of OEO make it possible to apply OEO to control V. vulnificus contamination in oysters and other seafoods.

A study was conducted to investigate the effect of oregano essential oil (OEO) and monensin sodium on the oxidative stability, colour, texture, and the fatty acid profile of lamb meat (m. Longissimus lumborum). Twenty Dorper x Pelibuey lambs were randomly divided into five treatments; control (CON), monensin sodium (SM, Rumensin 200® 33 mg/kg), a low level of OEO (LO, 0.2 g/kg dry matter (DM)), a medium level of OEO (MO, 0.3g/ kg DM), and a high level of OEO (HO, 0.4 g/kg DM). Dietary supplementation of OEO at any concentration lowered the compression strength in comparison with CON and SM. MO had the highest a* values (7.99) and fatty acid concentration (C16:1n7, C18:1n9c, C18:1n6c, C20:1n9, and C18:2n6c) during storage for 7 d at 3 °C. Lipid oxidation was not promoted (p > 0.05) by the moderated supplementation of oregano essential oil; however, OEO at 0.3 g/kg DM showed a slight lipid pro-oxidant effect. Dietary supplementation of MO and SM had the same effect on colour, tenderness, and the fatty acid profile of lamb (L. lumborum). It was demonstrated that oregano essential oil was beneficial for lambs feeding, and it could be a natural alternative to replace monensin in lamb diets with improvements in the quality of the meat.

This work describes an outstanding synthesis of poly(ε-caprolactone) nanoparticles of distinct sizes loaded (PCLNP/OEO) or not (PCLNP) with oregano (Origanum vulgare) essential oil (OEO) by the nanoprecipitation method in order investigate the antimicrobial properties against bacteria Escherichia coli and Staphylococcus aureus. OEO antimicrobial activity was achieved by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). FTIR spectra indicated that encapsulation of OEO by PCLNPs was successful. Scanning electron microscopy images revealed that PCLNP and PCLNP/OEO presented spherical shape with diameters around 150 nm, while PCLNP exhibited size distribution raging 158 to 300 nm and zeta potential ranging from -13.8 to -28.5 mV. Thermogravimetric analysis indicated an increase in initial temperature of weight loss for PCLNP/OEO. PCLNP with 80% wt. of OEO has exhibited the highest decrease of growth of bacteria, and MIC against S. aureus and E. coli and MBC only for E. coli, which indicate a promising alternative for designing stable antimicrobial nanoparticles for application in novel food active packaging.

Essential oils have unique functional properties, but their environmental sensitivity and poor water solubility limit their applications. Therefore, we encapsulated oregano essential oil (OEO) in chitosan nanoparticles (CSNPs) and used tripolyphosphate (TPP) as a cross-linking agent to produce oregano essential oil chitosan nanoparticles (OEO-CSNPs). The optimized conditions obtained using the Box–Behnken design were: a chitosan concentration of 1.63 mg/mL, TPP concentration of 1.27 mg/mL, and OEO concentration of 0.30%. The OEO-CSNPs had a particle size of 182.77 ± 4.83 nm, a polydispersity index (PDI) of 0.26 ± 0.01, a zeta potential of 40.53 ± 0.86 mV, and an encapsulation efficiency of 92.90%. The success of OEO encapsulation was confirmed by Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). The scanning electron microscope (SEM) analysis showed that the OEO-CSNPs had a regular distribution and spherical shape. The in vitro release profile at pH = 7.4 showed an initial burst release followed by a sustained release of OEO. The antibacterial activity of OEO before and after encapsulation was measured using the agar disk diffusion method. In conclusion, OEO can be used as an antibacterial agent in future food processing and packaging applications because of its high biological activity and excellent stability when encapsulated.

Origanum vulgare L. (oregano) is an aromatic plant with wide applications in the food and pharmaceutical industries. Cronobacter sakazakii, which has a high detection rate in powdered infant formula, adversely impacts susceptible individuals. Oregano essential oil (OEO) is a natural antibacterial agent that can be used to fight bacterial contamination. Here, OEO chemical compounds from eight oregano varieties were analyzed by gas chromatography–mass spectrometry and their antibacterial properties were assessed. The eight OEOs were clustered into two groups and were more diverse in group 2 than in group 1. Six compounds, including p-cymene, 3-thujene, γ-terpinene, thymol, carvacrol, and caryophyllene, were shared by eight OEOs. Among the eight oregano varieties, OEOs from O. vulgare sc2 had the strongest antibacterial activity against C. sakazaki, with the inhibition zone of 18.22mm. OEOs from O. vulgare jx, O. ‘Nvying’, O. vulgare ‘Ehuang’, and O. vulgare ssp. virens were also potent. Moreover, the antibacterial activity of OEOs was positively correlated with the relative content of thymol. As the main OEO antibacterial compound, thymol affected the normal growth and metabolism of C. sakazakii cells by destroying the bacterial membrane and decreasing the intracellular ATP concentration. Thus, in light of the antibacterial activity detected in the OEOs from the eight oregano varieties, this study provides a theoretical foundation for oregano cultivar management and development.

Microbial load can be controlled using either synthetic or natural preservatives. Particular interest has been focused on the potential application of plant essential oils as safer additives for meat. However, there is no published research on the use of essential oils during the meat drying process. This study was focused on enhancing the meat drying process. At first a value-added dried meat product by using oregano essential oil (OEO) to inhibit the growth of bacteria, and the sensorial response from assessors is presented. It was found that the application of the OEO in meat is effective in inhibiting Salmonella enteritidis and Escherichia coli. After 6 hours of drying at 55°C, 2 ml (0.038 ml l-1 air) and 1.5 ml (0.028 ml l-1 air) of OEO were considered the minimal inhibitory concentrations (MICs) against S. enteritidis and E. coli, respectively. Samples treated with 0.75 ml of OEO were more attractive for consumption compared with the control; at a higher concentration of OEO, the sensory quality of the food was affected. Next, the effect of modified blanching treatments on the drying behaviour of beef meat was evaluated by determining moisture ratio versus time curves and the influence on sensory quality of the resulted product. The 3 treatments under investigation were (1) oil treatment (2) steam blanching and (3) hot air blanching with 3 doses of oregano essential oil (1) 1.5 ml (2) 3 ml and (3) 6 ml. Each treatment had an effect on the drying time of the beef samples, however, the dose of oregano essential oil applied did not affect the drying process. The results showed that steam blanching was very effective reducing the drying time. Meanwhile, 1.5 ml and 3 ml hot air blanching samples and 1.5 ml oil treatment samples were judged as better from sensory point of view and the respondents considered that adding oregano essential oil enriched the pleasantness of the smell. In conclusion, a value-added dried meat product obtained by using oregano essential oil to enhance food safety received an acceptable sensorial response from consumers. Additionally, each modified blanching treatment tested influences the drying kinetics process, but the dose of oregano applied did not affect the drying process. In this sense, hot air blanching and oil treatment with the lowest dose had an acceptable sensorial response from consumers.

Mestrado em Engenharia Alimentar - Instituto Superior de Agronomia
FucoPol is an exopolysaccharide produced by the Enterobacter A47, using glycerol byproduct from the biodiesel industry as carbon source. In this work, the potential of this biopolymer to produce microparticles and to encapsulate bioactive compounds by spray drying was studied. The particles were characterized in terms of morphology (Scanning Electron Microscopy), crystallinity (X-Ray Diffraction), chemical characteristics (Fourier Transform Infrared), and thermal properties (Thermogravimetric Analysis and Differential Scanning Calorimetry). FucoPol was able to form spherical microcapsules (size from 0.5 to 26.7 μm) with a thin wall (thickness from 222 to 1094 nm) and a smooth surface. A population of small particles with dented surfaces was obtained. The microcapsules presented an amorphous structure. Gallic acid (GA) and oregano essential oil (OEO) were encapsulated using FucoPol as wall material. The bioactive loading was 12.2 wt.% and 3.1 wt.% for OEO and GA, respectively. Additionally, the encapsulation efficiency was 20% for OEO and 5.3% for GA. The release profile in simulated gastric (SGF) and intestinal (SIF) fluids revealed a total release, except for the GA in SGF, where 68% retention was observed. The compounds antioxidant capacity was not affected by the encapsulation process. From the results obtained, FucoPol reveals a good potential as microcapsules forming and encapsulating material

[EN] Chitosan films and coatings have been obtained, by incorporating different essential oils (EO) and using different homogenization conditions of the film forming emulsions, in order to obtain antifungal materials for fruit preservation. The effect of oleic acid (OA) on the stability of the initial emulsions and on the film properties was analysed. Coatings were applied to control fungal decay in strawberries. The blending of chitosan with methylcellulose (MC) was also used in coating applications to tomato plants and fruits to prevent fungal infections. The films' functional properties as a function of their composition were analysed, as well as their antimicrobial activity through in vitro and in vivo tests. OA incorporation in the chitosan films (1:1 wt. ratio) reduced water vapour permeability (WVP) values to about 50 % of those of net chitosan films, with a small positive effect of the microfluidization process. EO (cinnamon, thyme and basil) did not notably reduced the WVP values of the chitosan films but a significant improvement in water barrier capacity was induced when OA was also added at 1:1 or 1:0.5 CH:OA ratios. In contrast, lipids slightly promoted oxygen permeability of the films. Lipid addition decreased the film stretchability and stiffness, with a lesser impact on the resistance to break, slightly depending on the droplet sizes. Essential oils also modulated the mechanical behaviour of the films, depending on their composition. Thyme and basil EO greatly promoted film stiffness and resistance to break, whereas cinnamon oil slightly reduced these mechanical attributes. Optical properties of the chitosan films were also affected by lipid incorporation. OA reduced the film transparency and gloss depending on the concentration, but provoked small changes in the colour parameters and whiteness index. EO affected transparency to a lesser extent, but had greater impact on the colour coordinates and whiteness index of the chitosan films due to the selective light absorption of their compounds. EO blend with oleic acid mitigated the colour changes in the films. Likewise, blending of OA with EO significantly reduced the losses of volatiles during the film formation due to the promotion of the stability of the film forming emulsions. Films containing cinnamon EO were effective in reducing the growth of Aspergillus niger, Botrytis cinerea and Rhizopus stolonifer, although thyme and basil EO encapsulated in the films did not exhibit antifungal action against these three fungi. When chitosan-cinnamon EO coatings were applied to strawberries inoculated with R. stolonifer, they reduced the fungal decay of the fruits during 14 days, at 10 °C, at the same time that total coliform counts were maintained at the initial levels. Chitosan coatings with lemon essential oil were also active at controlling fungal decay in strawberries. These did not significantly affect the physicochemical parameters of strawberries throughout cold storage, while they slowed down the respiration rate of the fruits and enhanced the chitosan antifungal activity against B. cinerea. The coatings, with and without lemon EO, affected the strawberry volatile profile, although it was only sensory appreciated for samples coated with chitosan-lemon oil. Blend films of CH and MC (1:1) containing oregano EO caused phytotoxic problems at "3 Leaves" stage of tomato plants, although the total biomass and crop yield was not affected. In the "Fruit" stage, the treatments had no negative effects. Coatings reduced the respiration rate of tomatoes, diminished weight loss during postharvest storage and were effective to decrease the fungal decay of tomatoes inoculated with R. stolonifer. Migration of thymol and carvacrol from CH-MC films in food simulants could overcome the stablished specific migration limit (60 mg/kg) for food contact packaging materials in aqueous and low pH systems if films contain a 1:1 polymer essential oil weight ratio.
[ES] En la presente tesis doctoral se han desarrollado diferentes materiales antifúngicos para su uso en conservación de frutas. Para ello, se han incorporado diferentes aceites esenciales (AE) en recubrimientos y películas de quitosano (Q). Se ha analizado el efecto de la adición de ácido oleico (AO) y las condiciones de homogeneización sobre la estabilidad de las emulsiones y sobre las propiedades de las películas. Se ha estudiado el efecto de los recubrimientos de Q sobre el deterioro fúngico en fresas y el efecto preventivo frente a infecciones fúngicas de las mezclas de metilcelulosa (MC) con Q en plantas de tomate. Se ha estudiado el efecto de la composición de las películas sobre las propiedades funcionales de las mismas, así como su actividad antimicrobiana in vitro e in vivo. La incorporación de AO en las películas de Q (proporción 1:1) redujo la permeabilidad al agua (PVA) en un 50% comparado con la de Q puro. La microfluidización indujo un efecto positivo sobre dicha reducción. La adición de AE (hoja de canela, tomillo o albahaca) no supuso una disminución notable de los valores de permeabilidad obtenidos para las películas de Q. Cuando se añadió AO a las formulaciones de Q y AE (proporciones 1:1 o 1:2), se promovió una mejora significativa en la PVA de las películas. En cambio, la adición de lípidos aumentó ligeramente la permeabilidad al oxígeno, disminuyó la elasticidad y la rigidez, y produjo un menor impacto sobre la resistencia a la rotura. A su vez, la adición de AE modificó el comportamiento mecánico de las películas. Los AE de tomillo y albahaca aumentaron considerablemente la rigidez y la resistencia a la rotura, mientras que el AE de hoja de canela redujo estos parámetros ligeramente. La adición de lípidos a las películas de Q afectó las propiedades ópticas de las mismas. El AO redujo la transparencia y el brillo, en función de la concentración añadida. La adición de AE tuvo un mayor impacto sobre los parámetros de color y el índice de blancura. Las mezclas de AE y AO mitigaron estos cambios de color. Además, la incorporación de las mezclas AE-OA redujo las pérdidas de volátiles del AE durante la formación de las películas. Las películas formuladas con el AE de hoja de canela fueron efectivas contra el crecimientos de A. niger, B. cinerea y R. stolonifer, aunque los AE de tomillo y albahaca encapsulados en las películas no mostraron ninguna actividad antifúngica. La aplicación de los diferentes recubrimientos de Q AE de C en fresas inoculadas con R. stolonifer dio lugar a una reducción en el deterioro fúngico de los frutos almacenados durante 14 días a 10°C. Los recubrimientos de Q-AE de limón también fueron efectivos en el control del deterioro fúngico en fresas. Estos recubrimientos no afectaron significativamente los parámetros físico-químicos de las fresas durante el almacenamiento en refrigeración, disminuyeron la tasa de respiración de los frutos y acentuaron la actividad antifúngica del Q frente a B. cinerea. Tanto los recubrimientos con AE como los de Q puro modificaron el perfil de volátiles de las fresas, aunque estos cambios solo fueron apreciados sensorialmente en el caso de los frutos recubiertos con AE. Las mezclas de Q y MC que contenían AE de orégano causaron efectos fitotóxicos en plantas de tomate en el estadio "3 hojas", aunque no afectaron a la biomasa total. En el estadio "frutos" los tratamientos no tuvieron ningún efecto negativo. Los recubrimientos redujeron la tasa de respiración de los tomates, disminuyeron la pérdida de peso durante el almacenamiento post-cosecha y fueron efectivos contra el deterioro fúngico de tomates inoculados con R. stolonifer. La migración de los compuestos fenólicos timol y carvacrol, contenidos en las películas de Q-MC, podría superar el límite de migración específica establecido (60 mg/Kg) para materiales de envase en contacto con alimentos en los casos de sistemas acuosos y d
[CAT] En la present tesi doctoral s'han desenvolupat diferents materials antifúngics per al seu ús en conservació de fruites. Per a açò, s'han incorporat diferents olis essencials (OE) en recobriments i pel·lícules de quitosano (Q). S'ha analitzat l'efecte de l'addició d'àcid oleic (AO) i les condicions d'homogeneïtzació sobre l'estabilitat de les emulsions i sobre les propietats de les pel·lícules obtingudes. S'ha estudiat l'efecte dels recobriments de Q sobre la deterioració fúngica en maduixes i l'efecte preventiu enfront d'infeccions fúngiques de les mescles de metilcelulosa (MC) amb Q en plantes de tomaca. S'ha estudiat l'efecte de la composició de les pel·lícules sobre les propietats funcionals de les mateixes, així com la seua activitat antimicrobiana in vitro i in vivo. La incorporació de AO en les pel·lícules de Q (1:1) va reduir la permeabilitat al vapor d'aigua (PVA) en un 50% comparat amb la de Q pur. La microfluidització va induir un petit efecte positiu sobre aquesta reducció. L'addició de AE (fulla de canyella, C, timó, T, i alfàbrega, A) no va suposar una disminució notable dels valors de permeabilitat obtinguts per a les pel·lícules de Q. Quan es va afegir AO a les formulacions de Q i AE, es va promoure una millora significativa en la PVA de les pel·lícules. Per contra, l'addició de lípids va augmentar lleugerament la permeabilitat a l'oxigen, va disminuir l'elasticitat i la rigidesa, i va produir un menor impacte sobre la resistència al trencament. Al seu torn, l'addició de OE va modificar el comportament mecànic de les pel·lícules. Els OE de T i d'A van augmentar considerablement la rigidesa i la resistència al trencament, mentre que l'OE de C va reduir aquests paràmetres lleugerament. L'addició de lípids a les pel·lícules de Q també va afectar les propietats òptiques de les mateixes. L'AO va reduir la transparència i la lluentor, en funció de la concentració afegida. L'addició d'OE va tenir un major impacte sobre el paràmetres de color i l'índex de blancor. Les mescles d'OE i AO van mitigar aquests canvis de color. A més, la incorporació de les mescles OE-AO va reduir les pèrdues de volàtils de l'OE durant la formació de les pel·lícules. Les pel·lícules formulades amb l'OE de C van ser efectives contra el creixements d'A. niger, B. cinerea i R. stolonifer, encara que els OE de T i A encapsulats en les pel·lícules no van mostrar cap activitat antifúngica. L'aplicació dels diferents recobriments de Q OE de fulla de canyella en maduixes inoculades amb R. stolonifer va donar lloc a una reducció en la deterioració fúngica dels fruits emmagatzemats durant 14 dies a 10°C. Els recobriments de Q-OE de llimó també van ser efectius en el control de la deterioració fúngica en maduixes. Aquests recobriments no van afectar significativament els paràmetres fisicoquímics de les maduixes durant l'emmagatzematge en refrigeració, van disminuir la taxa de respiració dels fruits i van accentuar l'activitat antifúngica del Q enfront de B. cinerea. Tant els recobriments amb OE com els de Q pur van modificar el perfil de volàtils de les maduixes, encara que aquests canvis sol van ser apreciats sensorialment en el cas dels fruits recoberts amb OE. Les mescles de Q:MC que contenien OE d'orenga van causar efectes fitotòxics en plantes de tomaca en l'estadi "3 fulles", encara que no van afectar a la biomassa total. En l'estadi "fruits" els tractaments no van tenir cap efecte negatiu. Els recobriments van reduir la taxa de respiració de les tomaques, van disminuir la pèrdua de pes durant l'emmagatzematge post collita i van ser efectius contra la deterioració fúngica de tomaques inoculades amb R. stolonifer. La migració dels compostos fenòlics timol i carvacrol, continguts en les pel·lícules de Q-MC, podria superar el límit de migració específica establit (60 mg/Kg) per a materials d'envàs en contacte amb aliments en els casos de sistemes aquosos i d
Perdones Montero, Á. (2015). ANTIFUNGAL CHITOSAN-BASED FILMS AND COATINGS CONTAINING ESSENTIAL OILS FOR FRUIT APPLICATIONS [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/59413
TESIS

Este trabalho de Mestrado teve por objetivo avaliar a atividade antifúngica in vitro e em queijo Minas Padrão de duas formulações (A e B) de nanoemulsões encapsulando óleo essencial de orégano (Origanum vulgare) produzidas pelo método da temperatura de inversão de fases (método PIT). Cladosporium sp., Fusarium sp. e Penicillium sp. foram os fungos identificados nas amostras de queijo Minas Padrão deteriorados. Tais cepas foram utilizadas na avaliação da atividade antifúngica in vitro e em queijo Minas Padrão do óleo de orégano nanoemulsionado. Nos testes in vitro foram determinadas as concentrações mínimas inibitórias (CMI) do óleo essencial de orégano puro e nanoemulsionado sobre o Cladosporium sp., Fusarium sp. e Penicillium sp. Foram utilizadas fatias de queijo Minas Padrão para avaliar o efeito inibitório das nanoemulsões contendo óleo essencial de orégano. Por último foi avaliado o efeito inibitório das nanoemulsões durante o processo de maturação de queijos Minas Padrão. Determinaram-se valores de CMI para óleo essencial puro de 0,2; 0,3 µg/ml para Fusarium sp. e Penicillium sp., respectivamente. Enquanto para as duas formulações de nanoemulsão; os valores de CMI dependeram da quantidade de óleo essencial de orégano que estava contido nelas, obtendo-se valores de 0,26; 0,11 e 1,62 µg/ml para a formulação A de óleo de orégano nanoemulsionado sobre Cladosporium sp., Fusarium sp. e Penicillium sp., respectivamente, e CMIs de 0,32; 0,1 e 0,8 µg/ml para a formulação B de nanoemulsão sobre os mesmos gêneros de fungos. Os ensaios nas fatias de queijo evidenciaram que o efeito das CMIs, quando aplicadas na matriz alimentícia, foi nulo, permitindo o desenvolvimento normal dos fungos avaliados, da mesma forma se determinou a importância da atividade de água no crescimento fúngico. Já nos queijos em ambiente de maturação o efeito inibitório do óleo de orégano foi pouco satisfatório, o que indicou a importância do controle dos demais parâmetros ambientais no ambiente de maturação. Pode-se concluir que o óleo essencial de orégano nanoemulsionado apresentou efeito inibitório contra os gêneros de fungos avaliados. Quando controlados parâmetros ambientais como temperatura de armazenamento e atividade de água, seu efeito inibitório pode ser amplamente melhorado, apresentando-o como potencial alternativa na conservação dos alimentos.
This Master Thesis aimed to evaluate the in vitro antifungal activity and in Minas Padrão cheese of two formulations (A and B) of nanoemulsions encapsulating essential oil of oregano (Origanum vulgare) produced by the method of phase inversion temperature (PIT method). Cladosporium sp., Fusarium sp. and Penicillium sp. fungi were identified in deteriorated cheese samples. These strains were used in the evaluation of antifungal activity of oregano essential oil nanoemulsions, both in vitro and in cheese. Minimum inhibitory concentrations (MIC) of essential oil of pure oregano oil and nanoemulsions were determined. Cheese slices were used to evaluate the inhibitory effect of nanoemulsions containing essential oil of oregano. Finally the inhibitory effect of encapsulated oregano oil was tested during cheese ripening. MIC values determined for pure essential oil were 0.20 and 0.3 µg/ml for Fusarium sp. and Penicillium sp., respectively. As for the two nanoemulsion formulations, MIC values depended on the amount of essential oil of oregano which was contained therein, and the values for formulation A were 0.26, 0.11 and 1.62 µg/ml for Cladosporium sp., Fusarium sp. and Penicillium sp, respectively. For formulation B, the values of MIC were 0.32, 0.10 and 0.80 µg/ml. The tests on the cheese slices showed that the effect of MIC when applied in the food matrix was null, as the fungi growth was not avoided. As for the tests during cheese ripening, the inhibitory effect of oregano oil in nanoemulsions was unsatisfactory, which indicated the importance of controlling other environmental parameters in the maturation chamber. It can be concluded that the nanoemulsions of essential oil presented inhibitory effect against the genera of fungi evaluated. Controlled environmental parameters such as storage temperature and water activity, its inhibitory effect can be highly improved, and the nanoemulsions of oregano oil can be seen as a potential system for food preservation.

No presente trabalho avaliaram-se os efeitos do óleo essencial do orégano (Origanum vulgare L.) sobre a fertilidade, desenvolvimento ponderal de ratos Wistar, potencial teratogênico, bem como o desenvolvimento físico, motor e comportamental das progênies. A dosagem inicial do óleo essencial foi obtida através de ensaio in vitro frente a linhagens de isolados de Candida spp. O óleo foi extraído pelo processo arraste de vapor e analisado por cromatografia GC/MS. Constituíram-se cinco grupos experimentais com 10 machos e 30 fêmeas cada, um grupo controle negativo (GC-) que recebeu o veículo da emulsão do óleo de orégano (água destilada + Tween 80 0, 001%) um grupo controle positivo (GC+) que recebeu os compostos majoritários do óleo, timol 3% e terpine-4-ol 3%, e três grupos tratados com a emulsão contendo óleo essencial do orégano contendo 3% V / V (GO1), 9% V/ V (GO2) e 27% V / V (GO3). Os animais foram tratados diariamente por via oral usando sonda oro-gástrica flexível, com mesmo volume (10 mg / mL). Os machos foram tratados durante 91 dias, sendo 70 dias antes do acasalamento e 21 dias de acasalamento, após este período, os machos foram eutanasiados para coleta de órgãos para análise histopatológica, coleta de sangue e processamento dos órgãos sexuais para contagens espermáticas. As fêmeas foram tratadas antes (14 dias) e durante o acasalamento, gestação (21 dias) e lactação (21 dias). Metade das fêmeas prenhes sofreu cesariana no 21º dia de gestação, e os fetos foram usados para a avaliação de teratogenia. O restante das fêmeas pariu a termo, tiveram o comportamento maternal avaliado e as suas proles foram avaliadas a partir do nascimento, quanto às características de desenvolvimento e testes reflexos. Na puberdade, aos 65 dias, um filhote de cada sexo por ninhada foi eutanasiado para avaliação histopatológica e contagens espermáticas e aos 75 dias de idade um macho de cada ninhada teve seu comportamento testado em campo aberto. Na idade adulta a prole formou casais não consaguineos para a realização do comportamento sexual. Os resultados mostram que a administração do óleo essencial nas diferentes doses não interferiu no desenvolvimento ponderal de machos e fêmeas tratados nem das suas progênies (ANOVA p > 0,05). Nos machos, o óleo essencial de orégano interferiu diminuindo o número de células espermáticas, o número total de espermatozóides armazenados na cauda do epidídimo e os níveis de testosterona plasmática, na morfologia espermática o óleo aumentou o percentual de malformações espermáticas nos grupos tratados, de forma dose dependentes, igualmente no controle positivo. Nas fêmeas a taxa de acasalamento apresentou diferença estatisticamente significativa em relação ao grupo controle negativo nas duas doses mais altas de óleo essencial (9% e 27%). Na dose mais alta houve perdas pós-implantação, diferentes estatisticamente do GC-. Na avaliação esquelética dos fetos, houve diferença estatisticamente significativa no percentual geral de fetos com anomalias esqueléticas, em relação ao controle negativo, em 3%, 9% e GC+. Com relação às progênies, não houve alterações estatísticamente significativas nos grupos, no que se refere ao desenvolvimento ponderal, nos testes reflexos, nas contagens espermáticas e dosagem de testosterona plasmática realizadas na puberdade, no teste de campo aberto e no teste de comportamento sexual. Com base nos resultados obtidos, é possível concluir que a dose inicial (3%), considerada terapêutica, é segura para a reprodução de ratos Wistar, no entanto quando esta dose é aumentada para 9% e 27%, alterações nas variáveis reprodutivas dos machos podem acontecer.
In the present study were evaluated the effects of the essential oil of oregano (Origanum vulgare L.) on fertility and weight development of rats on the teratogenic potential as well as the physical, motor and behavioral of the progenies. The initial dose was obtained by in vitro against strains of Candida isolates spp. The oil was extracted by the process of steam drag chromatography and analyzed by GC / MS. Constituted five experimental groups with 10 males and 30 females each, a negative control group (GC-) who received vehicle emulsion emulsion of oil of oregano (distilled water + Tween 80 0, 001%) a positive control group (CG + ) receiving the major compounds from the oil, thymol 3% and terpine-4-ol 3% and three groups treated with the emulsion containing essential oil of oregano containing 3% V / V (GO1 ), 9% V / V (GO2) and 27% V / V (GO3). The animals were treated daily orally using orogastric tube flexible, with the same volume (10 mg / ml). Males were treated for 91 days with 70 days prior to mating and during mating 21 days, after this period, males were euthanized to collect organs for histopathology, blood collection and processing of sexual organs for sperm counts. Females were treated before (14 days) and during mating, gestation (21 days) and lactation (21 days). Half of pregnant females underwent cesarean section on day 21 of gestation, and the fetuses were used for the evaluation of teratogenicity. The rest of the females gave birth at term, had evaluated whether maternal behavior and their offspring were evaluated from birth, for the development traits and reflex tests. At puberty, 65 days, a pup of each sex per litter was euthanized for histopathological assessment and sperm counts at 75 days of age a male from each litter had tested their behavior in the open field. In adulthood the offspring formed consaguineos couples not to perform sexual behavior. The results showed that administration of essential oil at different doses did not affect the weight development of males and females treated or their progeny (ANOVA p> 0.05). In males, the essential oil of oregano interfered decreasing the number of sperm cells, total number of sperm stored in the cauda epididymis and plasma testosterone levels on sperm morphology oil increasing the percentage of sperm abnormalities in the treated groups in a dose dependent manner, equally positive control. In females mating rate was statistically significantly different compared to negative control group in the two higher doses of essential oil (GO2 and GO3). At the higher dose (GO3) losses occurred before and after deployment, the GC-statistically different. In assessing skeletal fetuses of females who underwent cesarean section, there was a statistically significant difference in the overall percentage of fetuses with skeletal anomalies, relative to the negative control in GO1, GO2 and GC +. Regarding progenies, no significant statistics changes in groups, with regard to weight development, testing reflexes, sperm counts and measurement of plasma testosterone at puberty, in open field test, in the test of sexual behavior Based on these results, we conclude that the initial dose (3%), considered therapy is safe for reproduction of rats, however when this dose is increased to 9% and 27%, changes in the male reproductive variables can occur.

Listeria monocytogenes é conhecida como um importante patógeno causador de doenças transmitidas por alimentos na última década. Apesar do número de casos por ano ser relativamente baixo, a infecção pode ser grave, com mortalidades acima de 30%. Pesquisas realizadas no Brasil relataram uma incidência de 32% em amostras de produtos cárneos, e o microrganismo foi encontrado em 80% das amostras lingüiças frescal de carne suína. Apesar dos recentes avanços nas tecnologias de controle de patógenos em alimentos, os consumidores têm procurado alimentos \"naturais\", isto é, submetidos a tratamentos menos agressivos e isentos de conservadores químicos. Antimicrobianos naturais são uma opção interessante, mas sua aplicação requer uma melhor compreensão de sua funcionalidade nos alimentos. Os óleos essenciais e seus compostos fenólicos estão se tornando agentes antimicrobianos naturais bastante populares, assim como a nisina, uma bacteriocina produzida por Lactococcus lactis subsp. lactis. Esta pesquisa foi desenvolvida para avaliar o efeito de óleo essencial de orégano (O.E.O.) e de nisina, individualmente ou em combinação, na inibição da multiplicação de Listeria monocytogenes Scott A in vitro (meio de cultura) e in situ -(lingüiça frescal suína). A atividade inibitória foi testada pela metodologia de difusão em poços, e os halos de inibição foram medidos 24 horas após a incubação à 37ºC. Foram testadas as concentrações 0,05%, 0,1%, 0,2%, 0,3%, 0,4% e 0,5% (v/v) de O.E.O. e 0, 100, 200, 400, 600, 800, 1000, 1200, 1400, 1600, 1800 e 2000 ppm de nisina. Quando o óleo essencial foi usado em combinação com a nisina foi observado um efeito sinérgico na inibição de L. monocytogenes. As concentrações que apresentaram o maior efeito contra o patógeno nos testes in vitro, ou seja 0,5% (v/v) O.E.O. com 200 ppm de nisina, foram utilizadas nos experimentos com três formulações diferentes lingüiça frescal, contendo pernil de porco, sal (2%), nitrito (0,015%), condimentos, emulsificantes e antioxidantes, experimentalmente contaminadas com L. monocytogenes Scott A (106 UFC/g). A multiplicação do patógeno foi monitorada no produto refrigerado a 5oC por até 10 dias, através da contagem em placas. Controles sem antimicrobianos também foram estudados. Os resultados indicaram que o O.E.O., usado isoladamente, não conferiu proteção ao alimento. A nisina causou uma redução de 2 log imediatamente após o contato com o microrganismo, mas durante o armazenamento, as células sobreviventes apresentaram a mesma taxa de multiplicação que na lingüiça controle (??0,05), mantendo as contagens 2 log inferiores as do controle por até 9 dias. Quando os dois antimicrobianos foram usados em combinação, a redução imediata após o contato foi de 4 log, e, quando comparado ao controle, a taxa de multiplicação durante o armazenamento a 5oC foi significativamente mais altas que no controle (??0,05). Entretanto, as amostras de lingüiça contendo esses antimicrobianos nas concentrações testadas não foram aprovadas nos testes sensoriais de aceitação (??0,05). Esses resultados indicam que a combinação desses antimicrobianos pode ser utilizada como uma barreira adicional para a multiplicação de L.monocytogenes em lingüiça frescal suína, mas os atributos sensoriais que conferem ao produto podem limitar sua aplicação.
Listeria monocytogenes has been recognized as an important foodborne pathogen for the past decade. Although the number of cases per annum is relatively low, the infections can be acute, with mortality up to 30%. In Brazil, some works reported that 32% of dairy meat products were contaminated with L. monocytogenes, and this organism was found in 80% of fresh pork sausage. In spite of modern improvements in food production techniques, the consumers are seeking for \"natural\" food products, i.e., not submitted to aggressive treatments or added of chemical preservatives. Natural antimicrobials are a promising option, but their application requires a better understanding of their functionality in foods. Naturally occurring antimicrobial agents, such as essential oils and their phenolic components, are becoming increasingly popular as preservation agents. Other compound with increased application in foods is nisin, a bacteriocin produced by Lactococcus lactis subsp. lactis. This study aimed to evaluate the antimicrobial effect of oregano essential oil (O.E.O.) and nisin, individually or in combination, on the inhibition of growth of Listeria monocytogenes Scott A in vitro (agar culture medium) and in situ (fresh pork sausage). The inhibitory activity was tested by the well diffusion method, measuring the inhibition halos after 24hours incubation at 37ºC. The concentrations tested were 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5% (v/v) for OEO and 0, 100, 200, 400, 600, 800, 1000, 1200, 1400, 1600, 1800 and 2000 ppm for nisin. When the essential oil was used in combination with nisin, a synergistic effect was observed for L. monocytogenes, i.e., the oil enhanced the activity of the bacteriocin. The combination 0.5% (v/v) O.E.O. with 200 ppm nisin presented the best results and was used to test the functionality in fresh pork sausage prepared with three different formulations, containing deboned minced pork meat, 2% salt and 0.015% nitrite, plus spices, emulsifier and antioxidant, and experimentally contaminated with L. monocytogenes Scott A (106 CFU/g). The growth of the pathogen was monitored in the refrigerated product (5oC) up to 10 days, by means of plate counting. Controls without antimicrobials were included in the experiments. Results indicated that O.E.O., used alone, was not effective. Nisin alone caused a 2-log reduction immediately after contact, but during storage the surviving cells presented the same multiplication rate as in the control (? ? 0.5), keeping the counts 2 log lower up to 9 days. When used in combination, the two antimicrobials caused a 4-log count reduction immediately after addition and, when compared to the control, the multiplication rate of the surviving cells during storage under refrigeration up to 10 days was significantly higher (? ? 0.5). However, samples containing these antimicrobials in the tested concentrations failed the sensorial acceptance tests (? ? 0.5). These results indicate that the combination of these antimicrobials can be an additional hurdle for the control of L. monocytogenes in fresh pork sausages, but the final sensorial attributes of the product may hamper their application.

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Essential oils (OEs) are natural plant extracts and many of them are active as antimicrobials. Origanum vulgare L. (oregano) essential oil (OEO) has a promising application field as a food preservative. Several in vitro and application studies has been carried to evaluate the activity of OEs as antimicrobials in foods, but are not found in the literature survey data application in mussels. In this study we evaluated the chemical composition and the antibacterial effect of OEO in fresh chilled mussels from Mytella falcata species. The chemical constituents of the studied OE were identified by gas chromatography-mass spectrometry and for activity we analyzed the count of Escherichia coli and aerobic mesophilic bacteria, total volatile bases and pH. The addition of OEO at 1.4% resulted in complete inhibition of E. coli inoculated, reduced growth aerobic plate count bacteria and inhibit the process of deterioration. The activity of the OEO is attributed mainly to its major component, carvacrol, which has recognized antibacterial activity. The results indicate that the OEO can be applied to support of the extension of shelf life and safety of fresh mussels.
Óleos essenciais (OEs) são extratos naturais de plantas, sendo muitos deles ativos como antimicrobianos. O óleo essencial de Origanum vulgare L. (orégano) (OEO) possui um promissor campo de aplicação como conservante de alimentos. Diversos estudos in vitro e de aplicação têm sido feitos para avaliar a atividade de OEs como antimicrobianos em alimentos, no entanto não são encontrados na literatura dados de pesquisas de aplicação em mariscos. Neste estudo avaliamos a composição química do OEO e seu efeito antibacteriano em mariscos in natura refrigerados da espécie Mytella falcata, conhecidos como sururu. Os constituintes químicos do OE estudado foram identificados por cromatografia gasosa acoplada à espectrometria de massas e para a atividade realizamos as análises de contagem de Escherichia coli e bactérias mesófilas totais, teor de bases voláteis totais e pH do sururu. A adição de OEO a 1,4% resultou na completa inibição da E. coli inoculada, diminuição do crescimento de bactérias mesófilas totais e tornou o processo de deterioração mais lento. A atividade do OEO é atribuída principalmente ao seu componente majoritário, o carvacrol, que possui atividade antibacteriana. Os resultados obtidos indicam que o OEO pode ser aplicado no auxilio da extensão do prazo de validade e segurança de sururus in natura.

碩士
輔仁大學
食品科學系碩士班
103
Oregano essential oil (OEO) is widely used as a food flavoring, and also shows antimicrobial and antioxidative capacities. Additionally, Chitosan (CH) has been demonstrated as an active polymer with antimicrobial activity, which is beneficial to food quality and safety. The objectives of this research aimed to prepare an active packaging material using biodegradable polylactide film incorporating with antimicrobial substances (chitosan and/or oregano), and evaluate its mechanical properties and antimicrobial potential. Solvent casting technique was accomplished to prepare antimicrobial film, then its functionality was determined according to releasing rate and inhibition of microbial growth. Mechanical properties (tensile strength, elongation at break and Young’s module), permeability (water vapor and O2 permeation), and stability (water absorption and degradability), as well as feasibility of food application were evaluated. Results showed that thickness of active films ranged 0.11~0.15 mm. Sufficient antimicrobial agent diffusing into agar plate to cause antimicrobial activity was found within 5 hours. In addition, PLA film incorporated with 3% blend of OEO and CH (1:1, w/w) resulted 4, 3 and 7 log CFU/mL reduction on S. aureus, E. coli and total total viable count, respectively, and those revealed a synergistic effect. With 3% antimicrobial agent incorporation, no significant difference in transparency was found. Moreover, this incorporation led to increase water absorption about 10%, however, no significant difference was found between pure PLA and 3% antimicrobial agent incorporation on degradability. Water vapor permeability increased about 1.5 g/m2/day while O¬2 permeation has 5 mL/m2/day reduction with 3% antimicrobial agent incorporation. Decrease of tensile strength, elongation at break and Young’s module was determined from 360.13 ± 45.12 MPa, 17.04 ± 1.63% and 22.36 ± 4.34 to 286.86 ± 39.89 MPa, 15.01 ± 0.47% and 19.19 ± 1.78, respectively. Antimicrobial films caused 0.5~0.8 and 0.2~0.5 log CFU/mL reduction of growth of S. aureus and E. coli, respectively, on packaged meat; however, the inbhitory effect is not sufficient to meet industrial demand. The findings in the present study demonstrated that antimicrobial film incorporatied with chitosan and oregano essential oil is characterized less substances addition, and no effectiveness on similar mechanical properties and flavor.

碩士
國立中興大學
獸醫學系暨研究所
102
Coccidiosis, a protozoal disease caused by genus Eimeria in chicken, creat tremendous economic losses in poultry industry worldwild every year. Infected chicken shows weakness, poor growth performances, decreased body weight, dysentery, bloody diarrhea, or even death. Traditional methods on treatment and prevention of coccidiosis, which were based on chemical anit-coccidial agents and vaccines, have been challenged harshly by drug-resistance and drug residue issues. Therefore, many herbal extracts have been found and researched extensively such as arteannuin from Artemisia annual and polysaccharide from mushrooms. In this research, the mixture of oregano essential oil（extract from Origanum vulgare）and garlic（Allium sativum）extract were tested of the preventive effects against E. tenella on Arbor Acres broilers and Leghorn layers. Three repetitions of experiments on Arbor Acres broilers had done. 50 birds were separated into 5 groups: negative control group（NEG), positive control group with 50,000 oocysts inoculated（POST50,000), preventive group with 50,000 oocysts inoculated（PRE50,000), pos8ritive control group with 5,000 oocysts inoculated（POST5,000）and preventive group with 5,000 oocysts inoculated（PRE5,000）respectively. The experiment on Leghorn layers devided 36 birds into 3 groups: negative control group（NEG), positive control group with 50,000 oocysts inoculated（POST50,000）and preventive group with 50,000 oocysts inoculated（PRE50,000). Inoculation was performed to 2-week-old chickens. Mixture of oregano essential oil and garlic extract which diluted 10,000 times into drink water had fed continuously for 3 days before inoculation of preventive groups in both experiments. Lower O.P.G. counts had shown in preventive groups of experiments on Arbor Acres broilers. Even though without statistically significancy, the measurements of body weight gain, intestine weight ratio and cecal lesion score in preventive groups were also better than positive control groups. Result of experiment on Leghorn layers also shown lower O.P.G. counts in preventive groups. Conclusively, 0.1％ mixture of oregano essential and garlic extract in drinking water could prevent E. tenella infection in Arbor Acres broilers and Leghorn layers, especially in O.P.G. counting, which makes this product potentially become a newly natural anticoccidial combination.