Volatile Essential Oils Research Articles

植物挥发油抗菌及驱虫作用研究进展

Volatile essential oils extracted from plants could produce good biological effects on the repelling and killing of insects,which seemed to be equivalent to or even better than chemical repellants.In addition,volatile essential oils had better advantages of safety,which was termed as a natural repellent.This paper summarized the antibacterial and repelling effects of essential oils on the human and plant bodies.Its application indicated that essential oils,as a natural repellent,had a broad prospect for development and application.

Elevated volatile concentrations in high‐nutrient plants: do insect herbivores pay a high price for good food?

1. A tritrophic perspective is fundamental for understanding the drivers of insect–plant interactions. While host plant traits can directly affect insect herbivore performance by either inhibiting or altering the nutritional benefits of consumption, they can also have an indirect effect on herbivores by influencing rates of predation or parasitism.2. Enhancing soil nutrients available to trees of the genus Eucalyptus consistently modifies plant traits, typically improving the nutritional quality of the foliage for insect herbivores. We hypothesised that resulting increases in volatile essential oils could have an indirect negative effect on eucalypt‐feeding herbivores by providing their natural enemies with stronger host/prey location cues.3. Eucalyptus tereticornis Smith seedlings were grown under low‐ and high‐nutrient conditions and the consequences for the release of volatile cues from damaged plants were examined. The influence of 1,8‐cineole (the major volatile terpene in many Eucalyptus species) on rates of predation on model caterpillars in the field was then examined.4. It was found that the emission of cineole increased significantly after damage (artificial or herbivore), but continued only when damage was sustained by herbivore feeding. Importantly, more cineole was emitted from high‐ than low‐nutrient seedlings given an equivalent amount of damage. In the field, predation was significantly greater on model caterpillars baited with cineole than on unbaited models.5. These findings are consistent with the hypothesis that any performance benefits insect herbivores derive from feeding on high‐nutrient eucalypt foliage could be at least partially offset by an increased risk of predation or parasitism via increased emission of attractive volatiles.

The Effect of Using Frankincense (Boswellia sacra) Chewing Gum on the Microbial Contents of Buccal/Oral Cavity, Taif, KSA

Frankincense (Boswellia sacra / Oleo-gum-resin), the main effective contents were alcohol-soluble resins is 78%, water-soluble gum 23% and volatile essential oil 7% respectively. The contents have anti- microbial effects, on moth flora. The target was to detect the anti-microbial effects on microbial contents of buccal/oral cavity which are the sources of infection. Selection was of 5 female persons aged (25-35yrs.), for the experiment under study as the usage of Frankincense chewing gum for 5hrs. continually. As well as they was tested for microbial contents of buccal/oral cavity through microbial identification of saliva. The main CFUs/ml saliva were 13.000, 8.200, 6.100, 3.900, 2.200, and 740 at Zero, 1, 2, 3, 4, and 5hrs. The differences of CFUs/ml saliva were 4.800, 2.100, 2.200, 1.700, and 1.460 between (Zero hr.-1hr.), (1hr.-2hr.), (2hr.-3hr.), (3hr.-4hr.), and (4hr.-5hr.) respectively. CFUs/ml saliva were 1.3X10 4 , 8.2X10 3 , 6.1X10 3 , 3.9X10 3 , 2.2X10 3 , and 7.4X10 2 at Zero, 1, 2, 3, 4, 5hr. respectively. Frankincense chewing gum is a safe and low-cost herbal product, applied to improve buccal/oral cavity hygiene by anti-microbial effects which decrease the sources of microbial infection in buccal/oral cavity and support mouth hygiene for all ages. It has been indicated to have wide pharmacological and industrial potentials as well.

Retracted] Essential Oils Loaded in Nanosystems: A Developing Strategy for a Successful Therapeutic Approach

Essential oils are complex blends of a variety of volatile molecules such as terpenoids, phenol-derived aromatic components, and aliphatic components having a strong interest in pharmaceutical, sanitary, cosmetic, agricultural, and food industries. Since the middle ages, essential oils have been widely used for bactericidal, virucidal, fungicidal, antiparasitical, insecticidal, and other medicinal properties such as analgesic, sedative, anti-inflammatory, spasmolytic, and locally anaesthetic remedies. In this review their nanoencapsulation in drug delivery systems has been proposed for their capability of decreasing volatility, improving the stability, water solubility, and efficacy of essential oil-based formulations, by maintenance of therapeutic efficacy. Two categories of nanocarriers can be proposed: polymeric nanoparticulate formulations, extensively studied with significant improvement of the essential oil antimicrobial activity, and lipid carriers, including liposomes, solid lipid nanoparticles, nanostructured lipid particles, and nano- and microemulsions. Furthermore, molecular complexes such as cyclodextrin inclusion complexes also represent a valid strategy to increase water solubility and stability and bioavailability and decrease volatility of essential oils.

Rice weevil response to basil oil fumigation

Basil oil, Ocimum basilicum L., is a volatile plant essential oil that is known to have insecticidal activity against stored product pests such as rice weevil, Sitophilus oryzae (L.). Basil oil was diluted in acetone and applied to a sponge held inside a tea strainer for fumigations in containers with and without rice. Basil oil fumigation (3ml, 10% concentration) caused high mortality in adult rice weevils when weevils were exposed in air in a sealed 1L plastic container. However, when basil oil was placed in packaged rice, weevil mortality was low and reproduction was not affected. Effectiveness of plant essential oil fumigation should be conducted under realistic conditions to avoid experimental artifacts and misleading results.

In vitro genotoxicity of Melaleuca alternifolia essential oil in human lymphocytes

Ethnopharmacological relevanceThe volatile essential oil derived from the plant Melaleuca alternifolia, also called tea tree oil (TTO), is largely employed for its antimicrobial properties against several human pathogens. It is used in many topical formulations to treat cutaneous infections. Aim of the studySince very few studies have been done on the safety and toxicity of the crude Melaleuca alternifolia essential oil, current investigation evaluates the possible genotoxic effects of TTO in human lymphocyte cultures. Material and methodsThe composition of current TTO sample was determined by GC/MS and NMR. The level of cytotoxicity in TTO treated cultures was determined by decrease of mitotic index when compared to that in negative control. The genotoxic potential of TTO was assessed by the in vitro mammalian cell micronucleus and the chromosome aberrations (CA) tests. ResultsTwenty-seven compounds were identified, accounting for 98.9% of the constituents. Terpinen-4-ol (42.8%), γ-terpinene (20.4%), p-cymene (9.6%), α-terpinene (7.9%), 1,8-cineole (3%), α-terpineol (2.8%) and α-pinene (2.4%) were the major compounds of the oil sample. None of the tested TTO concentrations (95μg/ml, 182μg/ml and 365μg/ml) caused a significant increase in the observed frequencies of micronuclei when compared to those in the untreated cultures (negative control). Additionally, no significant differences regarding the frequencies of CA were observed among the tested TTO concentrations and the negative control. ConclusionsResults demonstrate that TTO, in the tested concentrations, is not genotoxic in in vitro mammalian cells.

Encapsulation of cinnamon oil in b-cyclodextrin

Inclusion complexes between the Cinnamomum verum essential oil and b-cyclodextrin were prepared by co-precipitation method with the four oil to b-cyclodextrin ratios of 5:95, 10:90, 15:85 and 20:80 (w/w) in order to determine the effect of the ratio on the inclusion efficiency of b-cyclodextrin for encapsulating oil volatiles. The characterization of the complex involved the analysis of the initial essential oil, the surface and the total extracted oils. The retention of essential oil volatiles reached a maximum of 94.18% at the oil to b-cyclodextrin ratio of 10:90. Though, the maximum inclusion efficiency of b-cyclodextrin was achieved at the ratio of 15:85, in which the complex powder contained 117.2 mg of oil/g of b-cyclodextrin. Thirty-one flavor compounds were detected in the original oil and 21 compounds with the content higher than 0.10% were considered in complexation process. The qualitative and quantitative composition of the volatiles in the total oil extracts was similar to the starting oil. However the chromatographic profile of the surface adsorbed oil was different. The thirteen major flavor compounds, found in the commercial Cinnamomum verum essential oil, were present in all of the extracts, but in the different proportions between the total and surface oil extracts. Key words: Cinnamomum verum oil, b-cyclodextrin, inclusion complex, (E)-cinnamaldehyde.

Impaired Sense of Smell in a Drosophila Parkinson’s Model

Parkinson’s disease (PD) is one of the most common neurodegenerative disease characterized by the clinical triad: tremor, akinesia and rigidity. Several studies have suggested that PD patients show disturbances in olfaction at the earliest onset of the disease. The fruit fly Drosophila melanogaster is becoming a powerful model organism to study neurodegenerative diseases. We sought to use this system to explore olfactory dysfunction, if any, in PINK1 mutants, which is a model for PD. PINK1 mutants display many important diagnostic symptoms of the disease such as akinetic motor behavior. In the present study, we describe for the first time, to the best of our knowledge, neurophysiological and neuroanatomical results concerning the olfactory function in PINK1 mutant flies. Electroantennograms were recorded in response to synthetic and natural volatiles (essential oils) from groups of PINK1 mutant adults at three different time points in their life cycle: one from 3–5 day-old flies, from 15–20 and from 27–30 days. The results obtained were compared with the same age-groups of wild type flies. We found that mutant adults showed a decrease in the olfactory response to 1-hexanol, α-pinene and essential oil volatiles. This olfactory response in mutant adults decreased even more as the flies aged. Immunohistological analysis of the antennal lobes in these mutants revealed structural abnormalities, especially in the expression of Bruchpilot protein, a marker for synaptic active zones. The combination of electrophysiological and morphological results suggests that the altered synaptic organization may be due to a neurodegenerative process. Our results indicate that this model can be used as a tool for understanding PD pathogensis and pathophysiology. These results help to explore the potential of using olfaction as a means of monitoring PD progression and developing new treatments.

Analysis of volatile compounds in phytomedicines using thermal desorption gas chromatography mass spectroscopy

Volatile essential oils (EOs) from medicinal plants play an important role in the treatment of various diseases. EOs have been shown to exhibit anti-bacterial, antiviral, antimycotic, antitoxigenic, antiparasitic, and insecticidal properties [1]. Several commercial phytomedicines such as Olbas oil (www.olbas.co.uk) [2], Tiger balm (www.tigerbalm.com) and Mentholtum contain EOs from medicinal plants such as peppermint. Thermal desorption (TD) gas chromatography mass spectroscopy (GC-MS) is a very useful technique for the analysis of volatile compounds without using tedious pre-treatment with organic solvents. Here we have analysed and compared the composition of volatile compounds of Olbas oil, Tiger Balm, and Mentholtum using TD GC-MS. Volatiles from each product have been identified and quantified. Menthol and eucalyptol have been found to be present in all the products (Figure). The easy and sensitive TD GC-MS method is useful for the quality control of phytomedicines containing volatile compounds.

Influence of Plant Extracts and Essential Oils against Panama Disease (Fusarium oxysporum f. sp. cubense) in Banana Seedlings

The current research aimed to study the efficacy of plant extracts and essential oils from Rosmarinus officinalis, Thymus vulgaris, Cinnamomum zeylanicum and Syzigium aromaticum on mycelial growth and conidial germination of Fusarium oxysporum f. sp. cubense in vitro, as well as evaluation in vivo. Essential oils and extracts were applied in the culture medium (PDA) at melting point to estimate the direct effect on mycelial growth. Also, the estimation of volatile substances against mycelial growth was done. The obtained results indicated that plant extracts and essential oils of Cinnamomum zeylanicum and Syzigium aromaticum were effective at 500 ppm with direct effect against mycelial growth. The volatile plant extracts had no effect on mycelial growth, however, the volatile essential oils of Cinnamomum zeylanicum and Syzigium aromaticum showed good effects in controlling the disease in both 1000 and 2000 ppm. Meanwhile, extracts and essential oils of Cinnamomum zeylanicum and Syzigium aromaticum showed efficacy on the conidial germination. In vivo, both essential oils and extracts from Cinnamomum zeylanicum and Syzigium aromaticum, in addition to fungicide (Trifloxystrobin + Tebuconazole) which was effective in avoiding the spread of disease.

Fast gas chromatography combined with a high‐speed triple quadrupole mass spectrometer for the analysis of unknown and target citrus essential oil volatiles

The present research description is focused on the evaluation of a high-speed triple quadrupole mass spectrometer, carried out under moderately fast gas chromatography conditions (analysis time: 17 min). The mass spectrometric system is capable of operation under high-speed GC conditions, in both full-scan (maximum scan speed: 20,000 amu/s) and multiple reaction monitoring modalities. Furthermore, the triple quadrupole system can generate full scan and multiple reaction monitoring data simultaneously, also in a very rapid manner. A fast method was developed for the: (i) qualitative analysis of untargeted Citrus essential oil compounds, and (ii) the quali/quantitative analysis of targeted ones, namely three preservatives (o-phenylphenol, butylated hydroxytoluene, butylated hydroxy-anisole). The mass spectrometric system generated a more-than-sufficient number of data points/peak for both identification and quantification purposes. The level of sensitivity, reached through the multiple-reaction-monitoring side of the analysis, widely exceeded the requirements of current legislation. Method validation, related to the targeted analysis, was performed considering precision of retention times, peak areas and ion ratios; limits of detection/quantification, and accuracy were also measured.

English

Thymus vulgaris L. (garden thyme) is a member of the Lamiaceae family and is an indigenous aromatic and medicinal plant of Europe and Asia. At present, it is cultivated majorly in North America, Europe and North Africa in a large scale due to its economic importance. Thymus vulgaris L. is not accepted as a native plant of Turkey though some taxon is existing. However, it is commercially grown. The objective of this study was to examine the effects of P and K fertilizations on green herb yield, some herb chemical constituents (N, P, K) and volatile (essential) oil of Thymus vulgaris L. in order to recommend a reliable nutrient management for commercial growers. Results showed that, yield generally increase in accordance with the increases in K and P fertilizer rates. The N and P contents of the herb were measured higher under P rich (P2) conditions (that is, 67.5 + 67.5 = 135 kg P2O5 ha-1 from 15:15:15 + Zn and phosphoric acid, respectively). The highest three volatile oil constituents (compound) of the herb were found as thymol, paracymen and carvacrol.   Key words: Potassium (K), phosphorus (P), oil contents, volatile (essential) oil compound, thyme (Thymus vulgaris L.)

Preparation of phytoncide-emitting nylon/PP sheath/core fiber and the release profile of phytoncide

Phytoncide, a volatile essential oil produced by plants and trees, has not only anti-microbial activity, but also a stress relieving effect. We prepared a sheath/core type melt-spun fiber that releases phytoncide for a prolonged time. The fiber is comprised of a nylon sheath and a polypropylene (PP) core material. Phytoncide-containing microcapsules are embedded within the core part. The phytoncide microcapsule-containing nylon/PP sheath/core (M-Ny/PP) fiber has suitable mechanical properties for textile application. The phytoncide release from the microcapsule-containing the PP fiber (M-PP) reached a plateau level after 4 days and maintained that level for an additional 7 days, indicating a zero-order release after the initial burst. The M-Ny/PP fiber emitted the volatile phytoncide even though the fiber was spun at 250 °C. The release of phytoncide decreased in the M-Ny/PP fiber compared to the phytoncide microcapsule-containing PP (M-PP) fiber due to the dense sheath layer.

Making scents of defense: do fecal shields and herbivore-caused volatiles match host plant chemical profiles?

Many plant families have aromatic species that produce volatile compounds which they release when damaged, particularly after suffering herbivory. Monarda fistulosa (Lamiaceae) makes and stores volatile essential oils in peltate glandular trichomes on leaf and floral surfaces. This study examined the larvae of a specialist tortoise beetle, Physonota unipunctata, which feed on two M. fistulosa chemotypes and incorporate host compounds into fecal shields, structures related to defense. Comparisons of shield and host leaf chemistry showed differences between chemotypes and structures (leaves vs. shields). Thymol chemotype leaves and shields contained more of all compounds that differed than did carvacrol chemotypes, except for carvacrol. Shields had lower levels of most of the more volatile chemicals than leaves, but more than twice the amounts of the phenolic monoterpenes thymol and carvacrol and greater totals. Additional experiments measured the volatiles emitted from M. fistulosa in the absence and presence of P. unipunctata larvae and compared the flower and foliage chemistry of plants from these experiments. Flowers contained lower or equal amounts of most compounds and half the total amount, compared to leaves. Plants subjected to herbivory emitted higher levels of most volatiles and 12 times the total amount, versus controls with no larvae, including proportionally more of the low boiling point chemicals. Thus, chemical profiles of shields and volatile emissions are influenced by the amounts and volatilities of compounds present in the host plant. The implications of these results are explored for the chemical ecology of both the plant and the insect.

Fatty and Volatile Oils of the Gypsywort Lycopus europaeus L. and the Gaussian‐Like Distribution of its Wax Alkanes

AbstractThe detailed analyses of the volatile essential oil and lipid profiles of the aerial parts from the blooming and fruit‐forming stages of both ripe and unripe fruit of Lycopus europaeus (Lamiaceae) are presented. Both of these profiles are distinguished by components with a restricted occurrence in the Plant Kingdom. These rare compounds include (E)‐hotrienol in the volatiles, numerous unusual fatty acids (such as very long chain, odd‐numbered and branched‐chain) in the bound lipids and a high amount of iso‐ and anteiso‐alkanes in the epicuticular waxes. Furthermore, a Gaussian‐like distribution of the relative amounts of the epicuticular wax alkanes was observed. These normal distributions could be interpreted as the end result of the work of elongase enzyme systems where the Gaussian parameter μ should match the length of the “ideal” fatty acid biosynthesised and σ would represent the error of this enzyme system. These curve parameters were shown to have a close relationship with ACL and CPI values usually utilised to describe the natural distribution of wax alkanes. The screening of L. europaeus essential oil for its in vitro antimicrobial activity showed that this oil possesses selectivity towards two gram‐negative strains, E. coli and K. pneumoniae.

BIOLOGICALLY ACTIVE SUBSTANCES OF MEDICAL MUSHROOM GANODERMA LUCIDUM (CURT.:FR) P. KARST

The issue related the current data on the biologically active substances of medicinal basidiomycete Ganoderma lucidum and their actions. There were given the chemical formulas glucans and terpenoids – the substances that determine the main medicinal properties of the fungus. There were presented the information on the other substances involved in the forming of the therapeutic effect of Ganoderma: they were proteins and glicoproteins, nucleotides and nucleosides, sterols and steroids, fatty acids, alkaloids, glycosides, volatile essential oils and vitamins. In addition, Ganoderma as a xylotrophic-saprophyte has the set of ligninolytic enzymes which have been used in food processing, pulp and paper, and textile industries, as well as in the processes of biological treatment. Immunomodulatory, antimicrobial, antiviral and antitumor activities are confirmed by many experiments. The studies show the biological effects and mechanisms of action of G. lucidum metabolites.

Inhibitory Effects of Essential Oils for Controlling Phytophthora capsici.

Essential oils (EOs) were studied in vitro and in vivo for inhibiting Phytophthora capsici. Mycelial growth of P. capsici was examined on EO-amended media or after exposing it to EO volatiles. The efficacy of EOs was determined by estimating the effective concentration for 50% inhibition of P. capsici mycelial growth (EC50). Among 14 tested commercial products, oregano, palmarosa, and red thyme EOs had the lowest EC50 values (<0.15 μg/ml) for inhibiting the production and germination of sporangia and zoospores, and mycelial growth of P. capsici. The EOs had the same range of effect on inhibiting some mutant P. capsici isolates resistant to fluopicolide and zoxamide. P. capsici population in soil was reduced by the three EOs. Zucchini (Cucurbita pepo) fruit were protected against P. capsici infection when they were sprayed with red thyme (0.1 μg/ml) or oregano and palmarosa (0.2 μg/ml) EOs. Zucchini seedling emergence was affected by oregano, but not by red thyme. Zucchini seedlings survived in P. capsici-infested soil treated with red thyme at 0.1 μg/ml, while all of the nontreated seedlings died. These results taken together suggest that oregano, red thyme, and palmarosa EOs may be potential components for integrated management of P. capsici.

In vitro and in vivo antifungal activity of some essential oils against feline isolates of Microsporum canis

The treatment of dermatophytoses due to Microsporum canis is cumbersome and relapses can occur. Volatile essential oils (EOs) obtained from plants would seem to represent suitable tools to contrast mycoses both in human and animals. The anti-M.canis activity of some EOs chemically characterized was evaluated both in vitro and in vivo. Eleven feline isolates of M.canis were tested by microdilution against EOs extracted from Thymus serpillum, Origanum vulgare, Rosmarinus officinalis, Illicium verum and Citrus limon. A mixture composed by 5% O.vulgare, 5% R.officinalis and 2% T.serpillum, in sweet almond oil was administered to seven infected, symptomatic cats. T.serpillum and O.vulgare showed the lowest MICs, followed by I.verum, R.officinalis and C.limon. The assay performed on mixture showed that antimycotic activity of each component was enhanced. Four out of seven treated cats recovered both clinically and culturally. T.serpillum and O.vulgare EOs showed a strong antifungal activity. Preliminary data suggest a possible application in managing feline microsporiasis. Considering the potential zoonotic impact of this infection, the use of alternative antimycotic compounds would be of aid to limit the risk of environmental spreading of arthrospores.

Acacia nilotica: A plant of multipurpose medicinal uses

Acacia nilotica Lam (Mimosaceae) indigenously known as ‘Babul’ or ‘Kikar’ is a proverbial, medium sized tree and is broadly scattered in tropical and subtropical countries. It has an inspiring range of medicinal uses with potential anti-oxidant activity. This plant contributes a number of groups among which are alkaloids, volatile essential oils, phenols and phenolic glycosides, resins, oleosins, steroids, tannins and terpenes. A. nilotica is a medicinal plant acknowledged to be rich in phenolics, consisting of condensed tannin and phlobatannin, gallic acid, protocatechuic acid, pyrocatechol, (+) -catechin, (-) epi- gallocatechin-7-gallate and (-) epigallocatechin-5, 7-digallate. Different parts of this plant such as the leaves, roots, seeds, bark, fruits, flowers, gum and immature pods act as anti-cancer, antimutagenic, spasmogenic, vasoconstrictor, anti-pyretic, anti-asthamatic, cytotoxic, anti-diabetic, anti-platelet agregatory, anti-plasmodial, molluscicidal, anti-fungal, inhibitory activity against Hepatitis C virus (HCV) and human immunodeficiency virus (HIV)-I and antioxidant activities, anti-bacterial, antihypertensive and anti-spasmodic activities, and are also engaged for the treatment of different ailments in the indigenous system of medicine. This review spotlights on the detailed phytochemical composition, medicinal uses, along with pharmacological properties of different parts of this multipurpose plant.

Multiphoton fluorescence lifetime imaging shows spatial segregation of secondary metabolites in Eucalyptus secretory cavities

Multiphoton fluorescence lifetime imaging provides an excellent tool for imaging deep within plant tissues while providing a means to distinguish between fluorophores with high spatial and temporal resolution. Ideal candidates for the application of multiphoton fluorescence lifetime imaging to plants are the embedded secretory cavities found in numerous species because they house complex mixtures of secondary metabolites within extracellular lumina. Previous investigations of this type of structure have been restricted by the use of sectioned material resulting in the loss of lumen contents and often disorganization of the delicate secretory cells; thus it is not known if there is spatial segregation of secondary metabolites within these structures. In this paper, we apply multiphoton fluorescence lifetime imaging to investigate the spatial arrangement of metabolites within intact secretory cavities isolated from Eucalyptus polybractea R.T. Baker leaves. The secretory cavities of this species are abundant (up to 10 000 per leaf), large (up to 6 nL) and importantly house volatile essential oil rich in the monoterpene 1,8-cineole, together with an immiscible, non-volatile component comprised largely of autofluorescent oleuropeic acid glucose esters. We have been able to optically section into the lumina of secretory cavities to a depth of ∼80 μm, revealing a unique spatial organization of cavity metabolites whereby the non-volatile component forms a layer between the secretory cells lining the lumen and the essential oil. This finding could be indicative of a functional role of the non-volatile component in providing a protective region of low diffusivity between the secretory cells and potentially autotoxic essential oil.