In recent years, the use of essential oils (EOs) derived from aromatic plants as low-risk insecticides has increased considerably owing to their popularity with organic growers and environmentally ...conscious consumers. EOs are easily produced by steam distillation of plant material and contain many volatile, low-molecular-weight terpenes and phenolics. The major plant families from which EOs are extracted include Myrtaceae, Lauraceae, Lamiaceae, and Asteraceae. EOs have repellent, insecticidal, and growth-reducing effects on a variety of insects. They have been used effectively to control preharvest and postharvest phytophagous insects and as insect repellents for biting flies and for home and garden insects. The compounds exert their activities on insects through neurotoxic effects involving several mechanisms, notably through GABA, octopamine synapses, and the inhibition of acetylcholinesterase. With a few exceptions, their mammalian toxicity is low and environmental persistence is short. Registration has been the main bottleneck in putting new products on the market, but more EOs have been approved for use in the United States than elsewhere owing to reduced-risk processes for these materials.
In this study, total (non-fractionated) Farsi gumbased coatings (FGC) incorporated with clove (CEO) and Shirazi thyme (SEO) essential oils emulsions were utilized to extend the shelf-life of ...refrigerated rainbow trout fillets. Sonication decreased the amount of water insoluble fraction of FGC. Physicochemical, microbial and sensory characteristics of coated fillets were evaluated during 16 days. The results showed that incorporating CEO and SEO into FGC could significantly (p < 0.05) improve the quality of fish fillets. During storage, the increase in the amounts of peroxide value (PV), thiobarbituric acid reactive substances (TBARS), and total volatile basic-nitrogen (TVB-N) followed this order: CEO-SEO loaded FGC < FGC < uncoated (control). Regarding color parameters including L* and b* increased; whereas, a* decreased. Texture, odor, color and overall acceptability of coated fillets were significantly (p < 0.05) better than those of uncoated ones. A significant (p < 0.05) improvement in the microbial quality (total viable count (TVC), psychrophilic and lactic acid bacteria counts) was observed in the presence of essential oil-loaded coatings. Interestingly, an obvious synergistic effect was observed between CEO and SEO. The increase (>6 days) in the shelf-life was attributed to the antioxidant and antimicrobial characteristics of CEO and SEO.
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•Sonication decreased the insoluble fraction of total (non-fractionated) Farsi gum.•Significant synergistic effect between clove and Shirazi thyme essential oils.•More than double increase in the shelf-life after antimicrobial coating application.
In the last few years, essential oils (EOs) derived from plants have aroused great interest due to their well-known antimicrobial activity. Unfortunately, they present several limitations in their ...use, such as photosensitivity, temperature sensitivity, high volatility, and poor water solubility. The encapsulation technique represents a good solution to these problems and ensures protection of the functional properties of essential oils. In this work, bergamot essential oil (BEO) and sweet orange essential oil (OEO) loaded-Eudragit
RS 100 (EuRS100) nanoparticles (NPs) were prepared by using the nanoprecipitation technique. We obtained nanoparticles characterized by a mean diameter of 57 to 208 nm and a positive surface charge (39 to 74 mV). The antibacterial activity of the obtained systems against
was in vitro investigated. We demonstrated that both orange and bergamot essential oils were successfully encapsulated and our nanoparticles have good antibacterial activity. Finally, in order to evaluate the potential applicability of OEONps to prolong fresh orange juice shelf-life, survival of
during a storage period of one week at 25 °C was investigated: Orange essential oil-loaded nanoparticles (OEONPs) have been able to prolong the orange juice shelf life.
This study investigated the
effects of Greek oregano and garlic essential oils on inhibition of
parasites and their
effects on production performance, intestinal bacteria counts, and oocyst output. ...An inhibition assay was performed
using
Wisconsin strain sporozoites and Madin-Darby bovine kidney (MDBK) cells. Intracellular sporozoite invasion was quantified by detection of
DNA using qPCR from cell monolayers harvested at 2 and 24 h post-infection. Parasite invasion was inhibited by the oregano essential oil at the concentration of 100 μg/ml by 83 or 93% after 2 or 24 h, respectively. Garlic essential oil reached a maximum inhibition of 70% after 24 h with the 50 μg/ml concentration. Normal morphology was observed in MDBK cells exposed to concentrations of 100 μl/ml of garlic or oregano for over 24 h. In the
trial, 180 male broiler chicks (45.3 ± 0.7 g) were allocated into two treatments (6 pens of 15 chicks per treatment). Control treatment was fed commercial diets without antibiotics or anticoccidials. The ORE-GAR treatment was fed the same control diets, further supplemented with a premix (1 g/kg feed) containing the oregano (50 g/kg premix) and garlic (5 g/kg premix) essential oils. At day 37, all birds were slaughtered under commercial conditions, and intestinal samples were collected. ORE-GAR treatment had improved final body weight (1833.9 vs. 1.685.9 g;
< 0.01), improved feed conversion ratio (1.489 vs. 1.569;
< 0.01), and reduced fecal oocyst excretion (day 28: 3.672 vs. 3.989 log oocysts/g,
< 0.01; day 37: 3.475 vs. 4.007 log oocysts/g,
< 0.001). In the caecal digesta, ORE-GAR treatment had lower total anaerobe counts (8.216 vs. 8.824 CFU/g; p < 0.01), whereas in the jejunum digesta the ORE-GAR treatment had higher counts of
(5.030 vs. 3.530 CFU/g;
= 0.01) and
(5.341 vs. 3.829 CFU/g;
< 0.01), and lower counts of
(2.555 vs. 2.882 CFU/g;
< 0.01). In conclusion, the combined supplementation of oregano and garlic essential oils had a potent anticoccidial effect
and a growth-promoting effect in broilers reared in the absence of anticoccidial drugs.
► Oregano essential oil was encapsulated in chitosan nanoparticles. ► Oil presence in nanoparticles was corroborated by FTIR, TGA and XRD techniques. ► Particles had spherical shape and size range ...about 40–80nm. ► The release profile of the OEO showed burst effect followed by slow release.
In this study, oregano essential oil (OEO) has been encapsulated in chitosan nanoparticles by a two-step method, i.e., oil-in-water emulsion and ionic gelation of chitosan with sodium tripolyphosphate (TPP). The success of OEO encapsulation was confirmed by Fourier transform infrared (FT-IR) spectroscopy, UV–vis spectrophotometry, thermogravimetric analysis (TGA) and X-ray diffraction (XRD) techniques. The obtained nanoparticles exhibited a regular distribution and spherical shape with size range of 40–80nm as observed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). As determined by TGA technique, the encapsulation efficiency (EE) and loading capacity (LC) of OEO-loaded chitosan nanoparticles were about 21–47% and 3–8%, respectively, when the initial OEO content was 0.1–0.8g/g chitosan. In vitro release studies showed an initial burst effect and followed by a slow drug release.
Highly stable nanosized Pickering emulsion (PE) was prepared using clove bud natural essential oil stabilized with nanocellulose fiber. The PE was used to prepare gelatin/agar-based functional films. ...The PE was compatible with the polymer matrix and was evenly dispersed in the polymer matrix. The inclusion of PE slightly improved the mechanical strength and somewhat reduced the vapor barrier properties of the gelatin/agar-based film, with no significant difference in thermal stability. The addition of PE also provided excellent UV-barrier properties without sacrificing the transparency of the film. Besides, the composite film showed potent antioxidant activities. The PE-added gelatin/agar-based films with improved physical and functional properties are likely to be used in active food packaging applications.
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•Pickering emulsion was prepared using clove essential oil stabilized with nanocellulose fiber.•Gelatin/agar-based bioactive film was fabricated integrated with the Pickering emulsion.•The film showed good UV protection properties with high transparency.•The mechanical properties of the gelatin/agar film have been improved.•The Pickering emulsion added gelatin/agar film showed high antioxidant activity.
Repellent activity of essential oils: A review Nerio, Luz Stella; Olivero-Verbel, Jesus; Stashenko, Elena
Bioresource technology,
2010, 2010-Jan, 2010-01-00, 20100101, Letnik:
101, Številka:
1
Journal Article
Recenzirano
Currently, the use of synthetic chemicals to control insects and arthropods raises several concerns related to environment and human health. An alternative is to use natural products that possess ...good efficacy and are environmentally friendly. Among those chemicals, essential oils from plants belonging to several species have been extensively tested to assess their repellent properties as a valuable natural resource. The essential oils whose repellent activities have been demonstrated, as well as the importance of the synergistic effects among their components are the main focus of this review. Essential oils are volatile mixtures of hydrocarbons with a diversity of functional groups, and their repellent activity has been linked to the presence of monoterpenes and sesquiterpenes. However, in some cases, these chemicals can work synergistically, improving their effectiveness. In addition, the use of other natural products in the mixture, such as vanillin, could increase the protection time, potentiating the repellent effect of some essential oils. Among the plant families with promising essential oils used as repellents,
Cymbopogon spp.,
Ocimum spp. and
Eucalyptus spp. are the most cited. Individual compounds present in these mixtures with high repellent activity include α-pinene, limonene, citronellol, citronellal, camphor and thymol. Finally, although from an economical point of view synthetic chemicals are still more frequently used as repellents than essential oils, these natural products have the potential to provide efficient, and safer repellents for humans and the environment.
Menthol ranks with vanilla and citrus as one of the most important flavouring additives. The chemical and biological properties of menthol are reviewed. Display omitted
•Aspects of the chemistry and ...pharmacological properties of menthol are reviewed.•Menthol has found application in diverse fields; pharmaceutical, cosmetic, tobacco, food.•Numerous biological properties have been ascribed to menthol and the mint oils rich in menthol.•The mechanism by which this compound exerts its activity in vitro or in vivo is still poorly understood.
Menthol is a cyclic monoterpene alcohol which possesses well-known cooling characteristics and a residual minty smell of the oil remnants from which it was obtained. Because of these attributes it is one of the most important flavouring additives besides vanilla and citrus. Due to this reason it is used in a variety of consumer products ranging from confections such as chocolate and chewing gum to oral-care products such as toothpaste as well as in over-the-counter medicinal products for its cooling and biological effects. Its cooling effects are not exclusive to medicinal use. Approximately one quarter of the cigarettes on the market contain menthol and small amounts of menthol are even included in non-mentholated cigarettes. Natural menthol is isolated exclusively from Mentha canadensis, but can also be synthesised on industrial scale through various processes. Although menthol exists in eight stereoisomeric forms, (−)-menthol from the natural source and synthesised menthol with the same structure is the most preferred isomer. The demand for menthol is high and it was previously estimated that the worldwide use of menthol was 30–32,000 metric tonnes per annum. Menthol is not a predominant compound of the essential oils as it can only be found as a constituent of a limited number of aromatic plants. These plants are known to exhibit biological activity in vitro and in vivo such as antibacterial, antifungal, antipruritic, anticancer and analgesic effects, and are also an effective fumigant. In addition, menthol is one of the most effective terpenes used to enhance the dermal penetration of pharmaceuticals. This review summarises the chemical and biological properties of menthol and highlights its cooling effects and toxicity.
Hypericum perforatum L., olive oil, Origanum and Salvia species are used for inflammatory disorders and wound healing in traditional Turkish medicine. A new ointment formulation was developed to ...ensure more efficient wound healing based on the traditional knowledge.
Hypericum perforatum L. (Hypericaceae), olive oil (Oleaceae), Origanum Tourn ex L. and Salvia L. species (Lamiaceae) are used against inflammatory disorders and for healing of skin wounds in traditional Turkish medicine. A new ointment formulation was developed to provide more efficient wound healing activity. The content of the formulation was as follows; olive oil extract of flowering aerial parts of Hypericum perforatum L., olive oil, an equivalent mixture of Origanum majorana L. and Origanum minutiflorum Schwrd. et Davis essential oils (Origani aetheroleum), Salvia triloba L. essential oil. The aim of the present study is to assess the wound healing potential of this new formulation by using in vivo and in vitro models as well as histopathological methods.
For the evaluation of wound healing potential of this formulation (HPP crème mit Rotöl ointment) in vivo wound healing experimental models were employed on rats and mice and the efficiency was comparatively assessed against a reference ointment Madecassol®. Tissue sections were also evaluated histopathologically. Furthermore, the wound healing activity of each component was also investigated individually to determine the improvement in the healing capacity of the formulation.
The ointments of HPP crème mit Rotöl and Hypericum perforatum L. demonstrated the highest activities on both wound models when compared to reference ointment Madecassol®, while the other ingredients did not show any remarkable wound healing effect. However, the efficacy of the formulation was remarkably higher than the Hypericum L. ointment alone which was also confirmed by histopathological evaluation. On the other hand, the formulation did not reduce elastase activity in vitro, but inhibited the collagenase activity. HPP crème mit Rotöl also exerted bactericidal and candicidal activities.
The experimental studies revealed that HPP crème mit Rotöl formulation displays remarkable wound healing activity. To be acting on the different stages of wound healing process could be considered as a beneficial effect of the formulation for the treatment of wounds.
Essential oils are valuable natural products extracted from flowers, leaves, fruits, fruit rinds seeds, stems, roots, barks, or resins of various plants. They are used as raw materials in many ...fields, including perfumes, cosmetics, spices, foods, nutrition and treatment for several health disorders. Essential oils are complex mixtures comprising many single compounds. There are several methods for extracting the essential oils. Various researchers reported biological activities of essential oils. However, activities of the same essences are different from the extracted oils. This variation could be understood by studying the factors which influence the chemical composition of the essential oils, in particular under photochemical conditions. This review discusses the major components present in the essential oils, the methods of extraction from plants, stability, photochemical reactions of essential oil and their important components under different conditions and biological activities of essential oils.
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