A general method to spin-label a fatty acid was demonstrated as well as an assay of the effectiveness of methyl 10-undecenoate and the spin-labeled version, against the larvae of Aedes aegypti. The LCs were 66 and 58 μL/120 mL (55 and 48 ppm) respectively, and the LCs were 108 and 90 μL/120 mL (113 and 90) ppm. This shows that the spin-label has very little effect on the larvicidal activity of the compound.
View Article and Find Full Text PDFThe nutritional integrity of wheat is jeopardized by rapidly rising atmospheric carbon dioxide (CO) and the associated emergence and enhanced virulence of plant pathogens. To evaluate how disease resistance traits may impact wheat climate resilience, 15 wheat cultivars with varying levels of resistance to Fusarium Head Blight (FHB) were grown at ambient and elevated CO. Although all wheat cultivars had increased yield when grown at elevated CO, the nutritional contents of FHB moderately resistant (MR) cultivars were impacted more than susceptible cultivars At elevated CO, the MR cultivars had more significant differences in plant growth, grain protein, starch, fructan, and macro and micro-nutrient content compared with susceptible wheat.
View Article and Find Full Text PDFThe use of essential oils as ecofriendly tools for vector management is one of the mainstreams for biopesticide research. We evaluated the larvicidal properties of Commiphora erythraea (opoponax) essential oil and its fractions against Culex restuans Theobald, Culex pipiens L., and Aedes aegypti L.
View Article and Find Full Text PDFAlthough significant amounts of polymers associated with adverse health effects in oils are produced during frying, the chemical bonds forming these polymers are not well understood. This study revealed that ester bonds are responsible for the polymerization of soybean oil during frying and heating at 175 °C. The ester value of soybean oil increased during frying up to day 3 of the experiment and slightly decreased on day 4 of the experiment indicating that esterification and hydrolysis concomitantly occurred.
View Article and Find Full Text PDFSynthetic pesticides are the cornerstone of vector-borne disease control, but alternatives are urgently needed to tackle the growing problem of insecticide resistance and concerns over environmental safety. Leptospermum scoparium J.R.
View Article and Find Full Text PDFBackground: Some plant essential oils have insecticidal properties against mosquitoes and can be harnessed as ecofriendly tools for mosquito control. We conducted bioassays to determine the toxicity of Italian honeysuckle (Lonicera caprifolium) essential oil and its fractions against larvae of the yellow fever mosquito, Aedes aegypti.
Results: Sixteen constituents were identified in honeysuckle essential oil compared to 15, 15, 15, and 11 constituents in fractions A, B, C, and E, respectively.
Invasive alien plants wreak havoc on native ecosystems and using them as a source of biopesticides could improve their management. We examined the toxicity of essential oil of wild carrot (also known as 'Queen Anne's Lace', Daucus carota Linnaeus), an aggressive invader throughout the United States, against Aedes aegypti L., Culex pipiens L.
View Article and Find Full Text PDFEssential oils are potential alternatives to synthetic insecticides because they have low mammalian toxicity, degrade rapidly in the environment, and possess complex mixtures of bioactive constituents with multi-modal activity against the target insect populations. Twenty-one essential oils were initially screened for their toxicity against Aedes aegypti (L.) larvae and three out of the seven most toxic essential oils (Manuka, oregano, and clove bud essential oils) were examined for their chemical composition and combined toxicity against Ae.
View Article and Find Full Text PDFRecently, the decarboxylation of oleic acid (9()-octadecenoic acid) catalyzed by triruthenium dodecacarbonyl, Ru(CO), to give a mixture of heptadecenes with concomitant formation of other hydrocarbons, heptadecane and C17 alkylbenzenes, was reported. The product mixture, consisting of about 77% heptadecene isomers, 18% heptadecane, and slightly >4% C17 alkylbenzenes, possesses acceptable diesel fuel properties. This reaction is now applied to other fatty acids of varying chain length and degree of saturation as well as double-bond configuration and position.
View Article and Find Full Text PDFA gene encoding a synthetic truncated Candida antarctica lipase B (CALB) was generated via automated PCR and expressed in Saccharomyces cerevisiae. Western blot analysis detected five truncated CALB variants, suggesting multiple translation starts from the six in-frame ATG codons. The longest open reading frame, which corresponds to amino acids 35-317 of the mature lipase, appeared to be expressed in the greatest amount.
View Article and Find Full Text PDFA method to evaluate adhesives has been developed and used to reformulate a recently patented adhesive which is based on sugar and citric acid. Factors affecting adhesive performance were uncovered, such as an optimal curing temperature of 60°C. The addition of maltodextrin and soy protein at optimized levels was shown to nearly double the bonding strength of the adhesive, from 0.
View Article and Find Full Text PDFA synthetic Candida antarctica lipase B (CALB) gene open reading frame (ORF) for expression in yeast was constructed, and the lycotoxin-1 (Lyt-1) C3 variant gene ORF, potentially to improve the availability of the active enzyme at the surface of the yeast cell, was added in frame with the CALB ORF using an automated PCR assembly and DNA purification protocol on an integrated robotic workcell. Saccharomyces cerevisiae strains expressing CALB protein or CALB Lyt-1 fusion protein were first grown on 2% (w/v) glucose, producing 9.3 g/L ethanol during fermentation.
View Article and Find Full Text PDFJ Agric Food Chem
September 2009
A facile (and environmentally friendly) reaction between epoxidized methyl oleate and aniline to produce an oleate-aniline adduct, without the formation of fatty amide, was discovered. This reaction was carried out neat, with a catalytic amount of an ionic liquid. No solvent was used, no byproducts were produced, and the ionic liquid could be recovered and recycled.
View Article and Find Full Text PDFFive branched oleochemicals were prepared from commercially available methyl oleate and common organic acids; and their lubricant properties were determined. These branched oleochemicals are characterized as 9(10)-hydroxy-10(9)-ester derivatives of methyl oleate. These derivatives show improved low temperature properties, over olefinic oleochemicals, as determined by pour point and cloud point measurements.
View Article and Find Full Text PDFJ Agric Food Chem
November 2005
The two-step syntheses of the cyclic carbonates carbonated methyl oleate (CMO) and carbonated methyl linoleate (CML) are reported. First, synthesis of epoxides through well-precedented chemical reactions of unsaturated fatty methyl esters with hydrogen peroxide and formic acid was accomplished. Next, a carbonation reaction with a simple tetrabutylammonium bromide catalyst was performed, allowing the direct incorporation of carbon dioxide into the oleochemical.
View Article and Find Full Text PDFThe literature hypothesis that "the optimization of enzyme catalysis may entail the evolutionary implementation of chemical strategies that increase the probability of quantum-mechanical tunneling" is experimentally tested herein for the first time. The system employed is the key to being able to provide this first experimental test of the "enhanced hydrogen tunneling" hypothesis, one that requires a comparison of the three criteria diagnostic of tunneling (vide infra) for the same, or nearly the same, reaction with and without the enzyme. Specifically, studied herein are the adenosylcobalamin (AdoCbl, also known as coenzyme B(12))-dependent diol dehydratase model reactions of (i).
View Article and Find Full Text PDFAn intriguing but controversial hypothesis has appeared that "The optimization of enzyme catalysis may entail the evolutionary implementation of chemical strategies that increase the probability of tunneling and thereby accelerate the reaction rate" (Kohen, A.; Klinman, J. P.
View Article and Find Full Text PDFThe compound 8-methoxy-5'-deoxyadenosylcobalamin (8-MeOAdoCbl), has been synthesized in 37% yield and > or = 95% purity by HPLC, monitored at both 254 and 525 nm, or 90+/-2% purity as judged by the (1)H NMR spectrum of the aromatic cobalamin region. This is the first synthesis of this complex in which sufficient details are reported, where a yield and purity are reported, and where key problems in the synthesis and purification are overcome, so that 8-MeOAdoCbl can actually be obtained for use in other studies. Also demonstrated is the clean Co-C bond homolysis of 8-MeOAdoCbl to give initially 8-MeOAdoCbl and Co(II)Cbl in a UV-visible thermolysis experiment at 110 degrees C, results which show that the 8-MeO moiety suppresses the cyclization to the 8,5'-anhydro-adenosine otherwise seen for the adenosyl radical (Ado)*.
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