Methyl Nonyl Ketone Research Articles

Nation-wide monitoring campaign of 49 biocides and surfactants in surface waters and wastewaters

Despite their intensive use and their impact on ecosystems, biocides and surfactants are still poorly regulated and poorly monitored at large scale. In the frame of the revision of the national regulatory surveillance plan of surface waters, France planned in 2018 a monitoring campaign at national scale focused on these two types of substances of very emerging concern. Forty-nine contaminants (32 biocides and 17 surfactants) were investigated in surface water and sediment samples from 91 sampling sites, and in effluent and sludge samples of 7 wastewater treatment plants (WWTP), in mainland France and overseas regions. Between 33 and 52 % of the target contaminants were quantified at least once in water and sediment. High frequencies of quantification were observed for the surfactants (up to 91 % in water samples and up to 57 % in sediment samples for LAS C10-C13) and for the biocides (up to 64 % for fipronil in water samples and up to 90 % for methyl nonyl ketone in sediment samples). The median concentrations of surfactants were up to 2 μg/L in mainland surface water samples and up to 528 μg/kg in sediment samples, and for biocides, the median concentrations were up to 0.18 μg/L in mainland surface water samples and up to 104 μg/kg in sediment samples. PNEC exceedances in water and sediment were determined for both types of substances. The analysis of effluent and sludge suggested significant but not total removal of these substances in the WWTP. Temporal and spatial variations of the concentrations of both types of substances in surface water samples were also observed, suggesting both punctual and diffuse contamination sources of the surface water investigated.

Study of Manganese Laurate as Adsorbing Matrix for Undecan-2-one: Factors Affecting Adsorption for Application in Controlled-Release of Pheromones

One of the greatest challenges faced by agriculture is the use of agrochemicals and the balance between food production and environmental problems associated with the excessive use of these substances. To overcome this issue, pheromones have been used to trap pests that harm crops. This work reports the use of a layered monocarboxylate, manganese laurate (MnL2), as adsorbing matrix for undecan-2-one (methyl nonyl ketone (MNK)), one of the components of the pheromone of the insect Lobiopa insularis, which is a pest in the strawberry cultivar. The manganese laurate was synthesized by a coprecipitation method and was later characterized using X-ray diffractometry, vibrational spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. The characterization techniques showed that MNK was adsorbed in the manganese laurate structure in a range of 0.08 to 1.13 mg g-1, and this interaction was investigated in a factorial design experiment, in which the variables temperature, time of contact, and matrix:MNK ratio were investigated. A negative effect of increasing temperatures was observed and attributed to substrate volatilization. The adsorption was favored in increasing molar ratios and times of contact, and ideal conditions for the adsorption could be found, indicating that manganese laurate could be applied in controlledrelease tests.

2-undecanone alleviates asthma by inhibiting NF-κB pathway.

Asthma is characterized by airway inflammation and remodeling. 2-undecanone (methyl nonyl ketone), a volatile organic compound originating from Houttuynia cordata, has the potential to ameliorate inflammatory diseases. The present study aimed to explore potential benefits of 2-undecanone in asthma. 2-undecanone (100, 200 or 400 mg/kg) was administered intragastrically to ovalbumin (OVA)-challenged BALB/c mice. Lung tissues were collected to observe histopathological changes, and bronchoalveolar lavage fluid (BALF) was collected for inflammatory cells analysis and cytokine production. The results showed that 2-undecanone ameliorated OVA-induced pathologic changes of lungs, including reducing inflammatory cell infiltration, goblet cell hyperplasia, and airway smooth muscle thickness. The number of inflammatory cells and the levels of IL-4, IL-5, IL-13, and IgE in BALF were decreased by 2-undecanone in asthmatic mice. Furthermore, abnormal activation of NF-κB pathway in lung tissues of asthmatic mice was impeded by 2-undecanone. In vitro, 2-undecanone (12.5, 25, or 50 μM) suppressed platelet-derived growth factor-BB (PDGF-BB)-induced proliferation and migration of primary airway smooth muscle cells (ASMCs), and inhibited the switching of ASMCs from contractile phenotype to synthetic phenotype. Consistently, 2-undecanone blocked NF-κB activation in ASMCs. Collectively, 2-undecanone relieves asthma through alleviating airway inflammation and remodeling, and this beneficial effect is achieved by inhibiting NF-κB pathway.

Like or dislike: Response of rodents to the odor of plant secondary metabolites.

Rodents, including common voles (Microtus arvalis) and house mice (Mus musculus) cause immense pre-harvest and post-harvest losses. Therefore, developing methods that mitigate these losses while maintaining their role in ecosystems is a priority. Several plant secondary metabolites (PSM) which significantly reduce food intake of both species under laboratory conditions have been identified. However, before these can be used in rodent pest management, they must be tested under more natural conditions where other food sources are available. In this study, the odors of 4 PSMs were evaluated for their repellent effects in experiments conducted in semi-natural enclosures. Soil treated with PSMs or untreated soil (experimental control) was placed in an underground box containing food (rolled oats). We quantified the number of visits to each box and could demonstrate that all 4 PSMs reduced the number of visits to treatment boxes in both rodent species. For common voles the combination of methyl nonyl ketone + black pepper oil was the most repellent PSM. House mice made fewer visits to all PSM boxes; boxes with the anthraquinone were visited least. Furthermore, house mice consumed less food from boxes containing soil treated with all 4 PSMs. Our results suggest that PSMs are repellent in murid and microtine rodents under semi-field conditions. In addition, the future use of PSM odors for repelling both pest species, especially house mice, seems promising. Further investigations with other PSMs, different concentrations as well as alternative application methods are needed to repel common voles from attractive crops.

Aroma Profile of Fruit Juice and Wine Prepared from Cavendish Banana (Musa Sp., Group AAA) Cv. Robusta

A comparative study of the aroma profile of an alcoholic beverage (wine) and natural juice from banana cv. Robusta was performed. The study showed disappearance and synthesis of many aroma compounds during the fermentation process. Relative abundance of carbonyl compounds was high in the juice, and carboxylic acid content was higher in the wine. Aroma signature compounds of banana juice, isoamyl acetate, butyl isovalerate, isopentyl isovalerate, trans- 2- hexenal and butanoates were present only in a low proportion in the wine, while decanoic, dodecanoic and hexa decanoic acids (as well as their esters) were abundant in the banana wine. Synthesis compounds like methyl nonyl ketone, isoeuginol and 2-methoxy 4-vinyl phenol was greater during fermentation. Elemicin was present in high quantity in both the juice and the wine.

Efficacy of methyl nonyl ketone as an in‐soil repellent for common voles (Microtus arvalis)

Common voles (Microtus arvalis) can cause enormous damage in agriculture. Tests were conducted using an alternative approach to rodenticide-based vole management by developing an in-soil odour repellent based on the secondary plant metabolite methyl nonyl ketone (MNK). Replicated 25 m(2) plots were established in forage grassland to test efficacy and application schemes using a foam application that included MNK. MNK significantly reduced the number of reopened burrow entrances in all field trials compared with untreated control plots, with repeated application for 6 days reducing vole activity by up to 90%. The addition of black pepper oil (BPO) did not enhance the efficacy of the MNK foam. Voles tended to avoid burrows where MNK was applied and rather opened new burrows instead of reopening the treated burrow entrances. The foam application scheme led to a repellent effect that lasted for about 4-5 days. A single additional application of MNK after 4 days can extend the treatment effects for a further 2 days. The results indicate that MNK has the potential to repel common voles in the field. However, more studies are needed to enhance the duration of a one-off treatment effect to yield a user-friendly field application to manage vole populations.

The repelling effect of plant secondary metabolites on water voles, Arvicola amphibius

Water voles (Arvicola amphibius Linnaeus 1758) are abundant in most parts of Germany and other European countries. They are known to cause serious damage in fruit and horticulture as well as in agriculture. Currently available repellents, scaring devices and household remedies are mostly inefficient. Tests were conducted to establish whether water voles can be repelled using plant secondary metabolites. These compounds are produced by many plant species as part of their defence against herbivores and pathogens. In this study, 12 volatile substances were tested in T-maze trials. The voles could choose between a test box including a test substance and a control box without odour. The extracts were considered to be repellent if the test box was avoided. Five potential repellents were identified: the essential oils of black pepper oil, Chinese geranium oil and onion, as well as the pure substances methyl nonyl ketone and n-valeric acid. Application of a combination of black pepper oil, Chinese geranium oil and methyl nonyl ketone did not increase efficacy. The identification of an effective water vole repellent could help to reduce damage to crops. It may also minimise the use of kill traps and of rodenticides, which will be of benefit for non-target organisms.

Conclusion on the peer review of the pesticide risk assessment of the active substance methyl nonyl ketone

Conclusion on the peer review of the pesticide risk assessment of the active substance methyl nonyl ketone

A Combined Peritoneal Macrophage/Cell Membrane Chromatography and Offline GC–MS Method for Screening Anti-Inflammatory Components from Chinese Traditional Medicine Houttuynia cordata Thunb.

The aim of this study was to screen for the anti-inflammatory components from Houttuynia cordata Thunb (HCT) using an analytical method combining cell membrane chromatography (CMC) with gas chromatography–mass spectrometry (GC–MS). The stationary phase of the CMC employed mouse peritoneal macrophage (PM) cell membranes. We investigated the performance of the PM/CMC-offline-GC–MS method using hydrocortisone (HC) as standard. The method was then applied to the identification of anti-inflammatory components in extracts of HCT. The major component retained by CMC was identified as methyl nonyl ketone (MNK) by GC–MS. In vitro experiments revealed that MNK was able to inhibit LPS-induction of TNF-α, NO, and H2O2 production in a dose-dependent manner. IC50 values were 3.3, 4.1, and 3.6 μg mL−1, respectively. The PM/CMC-offline-GC–MS method is an effective screening system for the rapid detection, enrichment, and identification of target components from complex samples.

Determination of methyl nonyl ketone in volatile oil from herbs of Houttuynia cordata by GC-MS

To develop a GC-MS method for the determination of methyl nonyl ketone in the volatile oil from the herbs of Houttuynia cordata. The sample was split in the 240 degrees C injection port, with 20:1 split ratio, and separated on a DB-5 (30 m x 0.25 mm, 0.25 microm film thickness) fused silica column with helium as the carrier gas. The temperature program was as follows: 100 degrees C for 2 min, the 5 degrees C x min(-1) to 150 degrees C, then 15 degrees C x min(-1) to 200 degrees C, and kept for 10 min. The MS transfer line temperature was set to 250 degrees C, the MS source temperature was set to 200 degrees C. The ionization mode was electron ionization (EI) and the selective ion monitor mode was used. A good linear relationship was constructed over the injection amount range of 5.5-110 ng of methyl nonyl ketone. The average recovery was 98.9%, and RSD was 2. 2%. The developed method was sensitive, accurate, and can be used for the determination of methyl nonyl ketone in the volatile oil and for the quality control of H. cordata.

Determination and Pharmacokinetic Study of Methyl Nonyl Ketone in Rat Plasma by GC–MS

A rapid and sensitive method for determination of methyl nonyl ketone in rat plasma was developed based on GC–MS. The analyte and internal standard, propyl p-hydroxybenaoate, were extracted from plasma with methyl tert-butyl ether and then separated by an HP-5MS capillary analytical column (30 m × 0.25 mm, 0.25 µm) and determined by a quadrupole mass spectrometer detector operated under EI ionization and selected ion monitoring mode. Excellent linearity was found to be from 5.0 to 1,000 ng mL−1 with a lower limit of quantitation of 5.0 ng mL−1. The accuracy was between 96.0 and 106.3%, and the intra- and inter-day precision and accuracy values were found to be within the assay variability criteria limits according to the FDA guidelines. The developed method was successfully applied to the pharmacokinetic study of methyl nonyl ketone, a typical component in the traditional Chinese medicine Houttuynia cordata injection, in rats after a single oral dose of 100 mg kg−1 and peritoneal injection dose of 5 mg kg−1, respectively.

Release characteristics of the non-toxic insect repellant 2-undecanone from its crystalline inclusion compound with α-cyclodextrin

2-Undecanone (methyl nonyl ketone), a natural non-toxic insect repellant compound, was recently isolated from the trichomes of wild tomatoes, and is currently being introduced as a replacement for insect repellants containing N,N-diethyl-meta-toluamide or DEET, which are permitted for use on children older than 2 months. In an effort to improve the delivery of the somewhat volatile 2-undecanone, we have successfully formed the crystalline inclusion compound (IC) between 2-undecanone and α-cyclodextrin (α-CD), using a coprecipitation method. Employing WAXD, DSC, FT-IR, and NMR observations, we have confirmed that 2-undecanone is included as a guest inside the host α-CD cavities, and forms a channel-type crystalline IC. The release characteristics of 2-undecanone insect repellant from its α-CD-IC were studied using TGA either at a heating rate of 20 °C/min in nitrogen, and air atmospheres or at constant temperatures of 25, and 40 °C over a period of 24 h. The release/loss of 2-undecanone insect repellant from its α-CD-IC was ~60% after 24 h at 40 °C. By comparison, ~97% of pure 2-undecanone was volatilized, and lost over 24 h at 40 °C. In addition, insecticidal activity of 2-undecaonone from its α-CD complex against German cockroaches was evaluated. The results show an excellent repellency that 100% of the cockroaches were repelled for the first 2 days after application. These results suggest that the gradual, long-term delivery of the insect repellant 2-undecanone can be significantly improved through employment of its crystalline α-CD-IC.

Variation in Chemical Composition and Antibacterial Activities of Essential Oils from Two Species of Houttuynia THUNB.

Houttuynia THUNB. (Saururaceae) has been used for dozens of years in China for the treatment of cough, leucorrhea and ureteritis. The essential oils from the two species: Houttuynia emeiensis and Houttuynia cordata sold in China under one trade name 'Yuxingcao', obtained by hydrodistillation, were analyzed by GC-MS. The results show that fifty-five components were identified and methyl nonyl ketone (2.10-40.36%), bornyl acetate (0.4-8.61%) and beta-myrcene (2.58-18.47%) were the most abundant components in oil, but the percentage of most of compounds in different species and parts varied greatly. The two fold broth dilution and agar dilution method were used to study essential oil of two Houttuynia THUNB. species for their antibacterial properties against microorganisms, Staphylococcus aureus and Sarcina ureae. The two fold dilution method was allowed to determine the minimum inhibitory concentration (MIC) of essential oil from different parts and species. Results showed that all essential oils possessed antibacterial effect, with MIC values in the range of 0.0625 x 10(-3) to 4.0 x 10(-3) ml/ml. However, essential oil from different parts and species differed clearly in their antibacterial activities. The essential oil from the aboveground part of the cultivated Houttuynia emeiensis exhibited higher activity than both parts of the wild and cultivated Houttuynia cordata when used on Staphylococcus aureus (MIC = 0.25 x 10(-3) ml/ml) and Sarcina ureae (MIC = 0.0625 x 10(-3) ml/ml), and had the same activity as the positive control ampicillin sodium.

Cerium oxide-based catalysts for production of ketones by acid condensation

Cerium oxide-based catalysts proved superior in activity, selectivity, and stability to several other oxides for the condensation of two carboxylic acids to produce non-symmetric ketones. The effects of CeO 2 loading on the catalysts and the addition of more basic or acidic oxides to CeO 2 were also studied. The catalysts were characterized by surface area, XRD, and redox behavior using TGA. CeO 2-based catalysts began deactivating after >12 h operation at WHSV∼4, but could be completely regenerated by high temperature air. The optimum temperature range for methylcyclopropylketone (MCPK) production from acetic and cyclopropanecarboxylic acids (CCA) were 690–730 K, and 670–680 K for methylnonylketone (MNK) production from acetic and decanoic acids. The optimal loadings of CeO 2 on supports approached a monolayer, but the maximum yield appeared almost independent of support. Both acidic and basic oxide additives to CeO 2 increased the rates to isomers of both CCA and MCPK, and to aldol condensation products. Catalyst performance improved with respect to time on stream and the number of regeneration cycles. This behavior resulted from the gradual dispersion of CeO 2 on the support during reduction/oxidation cycles. Acetic acid/air could also be used to activate the catalysts prior to feeding the second acid.

Determination of Methyl Nonyl Ketone by Liquid Chromatography

Abstract A liquid chromatographic (LC) method has been developed to determine methyl nonyl ketone, a dog and cat repellent, In formulations. Corn cob formulations were extracted In acetonltrlle for 1 min using a Polytron mixer; liquid formulations were diluted with acetonitrile. A 10 juL aliquot was Injected Into a Vydac 218 TP54 column, monitored at 280 nm. The mobile phase was acetonitrlle-methanol-water-lsopropanol (225 + 200 + 50 + 25). Total analysis time was 5 min. Six different solid formulations and 5 different liquid formulations were analyzed 6 times with all percent coefficients of variation (% CV) below 4. Purity of each methyl nonyl ketone chromatographic peak was checked using a photodlode array detector In peak purity mode. No Interferences were observed at 280 nm.

The effectiveness of animal repellents on dogs and cats in the laboratory and field

A laboratory and field study of two animal repellents was conducted to determine the effectiveness of each on cats and dogs foraging from plastic garbage bags. In laboratory studies, 12 mixed-breed dogs, 18 beagle dogs and 8 cats were given a choice between commerical pet food in repellent-treated and non-treated plastic bags. Laboratory results showed that one repellent containing methyl nonyl ketone and cinnamic aldehyde reduced damage to bags 82.8% by mixed-breed dogs, 69.2% by beagle dogs, and 100% by mixed-breed cats. In the 3-month field study of 120 sites in urban ( n = 21), suburban ( n = 86) and rural ( n = 13) environments, the plastic bags contained fried chicken, paper and tin cans. At any given site, all bags were untreated (control) or sprayed with a repellent. Fifty-two percent of the damage to garbage bags was done by dogs alone, 6% by cats alone, 21% by dogs and cats, and 22% by raccoons either alone or at sites also damaged by cats and dogs. Only 17.8% of the control garbage remained undamaged for 1 week, 56% was damaged the first day they were placed on the site. Methyl nonyl ketone reduced damage to garbage bags by 31.4% and cinnamic aldehyde plus methyl nonyl ketone reduced damage by 40.1% in field studies. It was concluded that the laboratory study did not adequately simulate field conditions, and that neither repellent would be of practical value in preventing scavenging by animals. These results are in agreement with other studies looking at the efficacy of olfactory repellents with dogs. It is concluded that adequate restraint of dogs and cats is the only highly effective method of preventing garbage scavenging by these animals.

COMPOSITION OF HOP OIL

Preliminary separation of hop oil (from Humulus lupulus L. var. Bullion) by physical and chemical methods, followed by programmed gas-chromatography analysis of the individual fractions, revealed the presence of approximately 200 components. The hydrocarbon fraction (70% of the total oil) contained myrcene (30%), caryophyllene (20%), and humulene (40%), plus some 20 minor componentl (10%). The oxygenated fraction contained a complex mixture of alcohols (2-methys butanol, linalool, nerol, geraniol, nerolidol, etc.), carbonyls (methylnonyl ketone and numerous other methyl ketones, citral and other aldehydes), and esters of carboxylic acids having straight chains, branched chains and unsaturated straight and branched chains. Most of the identifications are based on gas chromatographic retention times and are tentative.

HOP OIL II. MAJOR CONSTITUENTS OF THE NON-SAPONIFIABLE FRACTION

Examination of the non-saponifiable constituents of the oxygenated fraction of hop essential oil has revealed the presence of 2-methyl butanol, linalool, methylnonyl ketone, methylundecyl ketone, geraniol, and the mono epoxides of caryophyllene and humulene as major constituents, together with three unidentified carbonyl compounds. Many other minor constituents are also present. Although geraniol is a major constituent of the non-saponifiable fraction, only traces of the free alcohol are present in the original oil.

INFLUENCE OF HOP OIL CONSTITUENTS ON THE FLAVOUR AND AROMA OF BEER

The sesquiterpenes caryophyilene, humulene, isocaryophyilene and “farnesene” have been found to occur in beer. These sesquiterpenes occur in conjunction with myrcene, methylnonyl ketone and other unidentified hop oil constituents.

ANALYSIS OF HOP OIL BY GAS-LIQUID PARTITION CHROMATOGRAPHY

Apparatus for analysis of hop aromatic oil by gas-liquid partition chromatography is described and analyses are reported for the principal components in the oils from commercial samples of 16 varieties of hops. Distinct peaks are obtained for as many as 13 components in the whole oil, but chromatography of the oxygenated fraction alone indicates that many additional components are present in small amounts. Myrcene and humulene comprise 70–80% of most oils but methyl nonyl ketone and two other compounds, believed to be β- and γ-caryophyllene, are present in substantial quantities. Analyses of the a-acid fractions of these hops are also reported and a highly significant correlation has been found between the myrcene content of the oil and the cohumulone content of the a-acid fraction, and also between the humulene content of the oil and the humulone content of the a-acid fraction. Oils from Continental European hops generally have a low myrcene and high humulene content while the reverse is true of North American hops.