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Lillian M Franklin et al.
Journal of agricultural and food chemistry, 65(12), 2549-2563 (2017-03-14)
In almonds, there is no standard method for detecting oxidative changes and little data correlating consumer perception with chemical markers of rancidity. To address this, we measured peroxide values (PV), free fatty acid values (FFAs), conjugated dienes, tocopherols, headspace volatiles...
S Fadda et al.
FEMS microbiology letters, 210(2), 209-214 (2002-06-05)
Staphylococcus carnosus strain 833, inoculated into sausage, increased the levels of methyl ketones which contributed to the cured aroma. These ketones were predicted to arise from incomplete beta-oxidation followed by a decarboxylation. To check this hypothesis, we measured the beta-decarboxylase...
Brian D Fitz et al.
Journal of chromatography. A, 1392, 82-90 (2015-03-31)
Low thermal mass gas chromatography (LTM-GC) was evaluated for rapid, high peak capacity separations with three injection methods: liquid, headspace solid phase micro-extraction (HS-SPME), and direct vapor. An Agilent LTM equipped with a short microbore capillary column was operated at...
S Schnell et al.
Biodegradation, 2(1), 33-41 (1991-01-01)
Strictly anaerobic bacteria were enriched and isolated from freshwater sediment sources in the presence and absence of sulfate with sorbic acid as sole source of carbon and energy. Strain WoSo1, a Gram-negative vibrioid sulfate-reducing bacterium which was assigned to the...
J Enrique Cometto-Muñiz et al.
Behavioural brain research, 201(1), 207-215 (2009-05-12)
We measured concentration-detection (i.e., psychometric) odor functions for the homologous ketones propanone (acetone), 2-pentanone, 2-heptanone, and 2-nonanone. Under a forced-choice procedure, stimuli were presented via an 8-channel air-dilution olfactometer that allowed natural sampling of the odorant and whose output was...
Jonathan J Grandy et al.
Journal of chromatography. A, 1410, 1-8 (2015-08-06)
In this work, a highly reproducible standard gas generating vial is proposed. The vial is comprised of a silicon diffusion pump oil spiked with an appropriate calibration compound, such as modified McReynolds probes (benzene, 2-pentanone, pyridine, 1-nitropropane, 1-pentanol, and n-octane)...
Yosuke Hanai et al.
Bioscience, biotechnology, and biochemistry, 76(4), 679-684 (2012-04-10)
Lung cancer is a leading cause of deaths in cancer. Hence, developing early-stage diagnostic tests that are non-invasive, highly sensitive, and specific is crucial. In this study, we investigated to determine whether biomarkers derived from urinary volatile organic compounds (VOCs)...
Silvina G Fadda et al.
Journal of agricultural and food chemistry, 50(9), 2471-2474 (2002-04-18)
Methyl ketones are detected in dry fermented sausages in which they contribute to the cured aroma. They have been associated with the inoculation of Staphylococcus carnosus used as starter culture. To evaluate the ability of bacterial starters to produce methyl...
Yasuhisa Asano et al.
Bioscience, biotechnology, and biochemistry, 69(12), 2349-2357 (2005-12-27)
We established a simple HPLC method to determine the activity and stereochemistry of the chiral mandelonitrile synthesized from benzaldehyde and cyanide, and applied it to screen for hydroxynitrile lyase (HNL) activity of plant origin. A total of 163 species of...
Patrick Hummel et al.
Protein science : a publication of the Protein Society, 14(3), 703-710 (2005-02-22)
We tested the Binding Threshold Hypothesis (BTH) for activation of olfactory receptors (ORs): To activate an OR, the odorant must bind to the OR with binding energy above some threshold value. The olfactory receptor (OR) 912-93 is known experimentally to...
Sandra van den Velde et al.
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences, 853(1-2), 54-61 (2007-04-10)
Halitosis can have an intra- or extra-oral origin. In all cases, bad breath is caused by the presence of volatile organic compounds originating from the mouth or the expired air. They can be specific for certain diseases or infections. This...
Organoleptic Characteristics of Flavor Materials
Mosciano, G.
Perfumer & Flavorist, 28, 76-76 (2003)
Ola Lasekan et al.
BMC chemistry, 13(1), 133-133 (2020-01-01)
The aroma chemistry and the contribution of the aroma compounds to the anti-oxidative properties of roasted yam have yet to be characterized. The growing popularity of roasted yam in regions where they are being consumed calls for a concerted effort...
Shane Avison et al.
Journal of agricultural and food chemistry, 63(28), 6313-6318 (2015-06-23)
A new methodology is presented to measure water-air partition coefficients (Henry's constants) of volatiles, using APCI-MS. Significant advantages over other Henry's constant determination methods include the short measurement and sample preparation time and the possibility for simultaneous measurement of multiple...
Linus Olofsson et al.
Organic & biomolecular chemistry, 3(5), 750-755 (2005-02-26)
The enantioselective reduction of 2-pentanone to (R)- and (S)-2-pentanol by Thermoanaerobacter (formerly Thermoanaerobium) brockii alcohol dehydrogenase (TBADH) in mixtures of water and water-miscible organic solvents was investigated. Significant enzymatic activity was retained in up to 87% methanol, ethanol and acetonitrile....
Jing Fan et al.
Journal of chromatography. A, 1399, 74-79 (2015-05-06)
This work presents the investigation of graphene as a new type of stationary phase for capillary GC separations. Graphene capillary column (0.25 mm, i.d.) achieved column efficiency of 3100 plates/m determined by n-dodecane at 120 °C. The obtained McReynolds constants...
Production of volatiles by ripening bananas.
Macku C & Jennings WG
Journal of Agricultural and Food Chemistry, 35(5), 845-848 (1987)
Silvina Fadda et al.
FEMS microbiology letters, 228(1), 143-149 (2003-11-13)
In sausage, Staphylococcus carnosus increases the levels of methyl ketones which could arise from incomplete beta-oxidation of fatty acids followed by a decarboxylation. The objective of this work was to characterize the beta-decarboxylase activities in cell-free extract. By using different...
Cheddar cheese flavour studies: II. Relative flavour contributions of individual volatile component.
Manning DJ
The Journal of Dairy Research, 46(3), 523-529 (1979)
Daniil Karnaushenko et al.
Advanced materials (Deerfield Beach, Fla.), 27(42), 6582-6589 (2015-09-24)
A novel method relying on strain engineering to realize arrays of on-chip-integrated giant magneto-impedance (GMI) sensors equipped with pick-up coils is put forth. The geometrical transformation of an initially planar layout into a tubular 3D architecture stabilizes favorable azimuthal magnetic...
J M Mathews et al.
Toxicology and applied pharmacology, 146(2), 255-260 (1997-11-05)
The effect of trans-1,2-dichloroethylene (DCE), an inhibitor of cytochrome P450 (P450) 2E1 (CYP2E1), on the composition and quantity of volatile organic chemicals (VOCs) expired in the breath of male F-344 rats was determined in parallel with hepatic P450 activity and...
Ellen Philippe et al.
Journal of agricultural and food chemistry, 51(5), 1393-1398 (2003-02-20)
Physicochemical parameters, such as hydrophobicity, water solubility, and volatility, of four flavor compounds (ethyl acetate, ethyl butyrate, ethyl hexanoate, and 2-pentanone) were determined. The amount of flavor compounds released from different model matrices (mineral water, purified triolein, an oil-in-water emulsion...
Giulia Caron et al.
Journal of medicinal chemistry, 48(9), 3269-3279 (2005-04-29)
Growing interest in the use of both the logarithm of the partition coefficient of the neutral species in the alkane/water system (log P(N)(alk)) and the difference between log P(N)(oct) (the logarithm of the partition coefficient of the neutral species in...
Studies on flavor components in soybean
Arai S, et al.
Agricultural and Biological Chemistry, 30(9), 863-868 (1966)
Jenny Pettersson et al.
Biological & pharmaceutical bulletin, 31(3), 534-537 (2008-03-04)
Many phytochemicals found in the diet may prevent colon carcinogenesis by affecting biochemical processes in the colonic mucosa. Inflammation and subsequent elevation of the enzyme cyclooxygenase-2 (COX-2) are two such factors involved in the development of colon cancer, and inhibition...
F J Kelling et al.
Medical and veterinary entomology, 16(2), 161-169 (2002-07-12)
The presence of background odour was found to have a small but significant effect on the sensitivity of the antennal olfactory system of houseflies, Musca domestica Linnaeus (Diptera: Muscidae), to new pulses of odour. We show that cross-adaptation and cross-sensitization...
Xiao-Hong Chen et al.
PloS one, 9(4), e94543-e94543 (2014-04-18)
A novel carbonyl reductase (AcCR) catalyzing the asymmetric reduction of ketones to enantiopure alcohols with anti-Prelog stereoselectivity was found in Acetobacter sp. CCTCC M209061 and enriched 27.5-fold with an overall yield of 0.4% by purification. The enzyme showed a homotetrameric...
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