Correlating Sensory Assessment of Smoke-Tainted Wines with Inter-Laboratory Study Consensus Values for Volatile Phenols.

Vineyard exposure to wildfire smoke can taint grapes and wine. To understand the impact of this taint, it is imperative that the analytical methods used are accurate and precise. This study compared the variance across nine commercial and research laboratories following quantitative analysis of the same set of smoke-tainted wines.

Glycosidically-Bound Volatile Phenols Linked to Smoke Taint: Stability during Fermentation with Different Yeasts and in Finished Wine.

When wine grapes are exposed to smoke, there is a risk that the resulting wines may possess smoky, ashy, or burnt aromas, a wine flaw known as smoke taint. Smoke taint occurs when the volatile phenols (VPs) largely responsible for the aroma of smoke are transformed in grape into a range of glycosides that are imperceptible by smell. The majority of VP-glycosides described to date are disaccharides possessing a reducing β-d-glucopyranosyl moiety.

Quantitation of Select Terpenes/Terpenoids and Nicotine Using Gas Chromatography-Mass Spectrometry with High-Temperature Headspace Sampling.

Plants are the main sources of many high-value bioactive terpenoids used in the medical, fragrance, and food industries. Increasing demand for these bioactive plants and their derivative products (e.g.

Development and Evaluation of a Vineyard-Based Strategy To Mitigate Smoke-Taint in Wine Grapes.

Smoke-taint is a wine defect that may occur when ripening grape crops absorb volatile phenols (VPs), compounds associated with the negative sensory attributes of smoke-taint, due to exposure of grapes to wildfire smoke. This study examined potential methods to reduce the impact that smoke-exposure has on wine grapes. Specifically, agricultural sprays normally used to protect grapes from fungal pathogens and a spray used to prevent cracking in soft-fleshed fruits were assessed for their capacity to inhibit increases in VP concentrations in wine grapes following on-vine smoke-exposure.

Smoke from simulated forest fire alters secondary metabolites in Vitis vinifera L. berries and wine.

The exposure of Vitis vinifera L. berries to forest fire smoke changes the concentration of phenylpropanoid metabolites in berries and the resulting wine. The exposure of Vitis vinifera L.

Detailed characterization of glycosylated sensory-active volatile phenols in smoke-exposed grapes and wine.

The exposure of Vitis vinifera L. vines to smoke from wildland fires can alter the chemical composition of the berries, such that the resulting wine can possess a defect known as smoke-taint. This work constitutes a complete method for the analysis of simple volatile phenol glycosides (VP-glycosides) that can be elevated in berries and wine following smoke exposure.

Chromatographic characterisation of 11 phytocannabinoids: Quantitative and fit-to-purpose performance as a function of extra-column variance.

Introduction: Cannabis sativa L. (cannabis) is utilised as a therapeutic and recreational drug. With the legalisation of cannabis in many countries and the anticipated regulation of potency that will accompany legalisation, analytical testing facilities will require a broadly applicable, quantitative, high throughput method to meet increased demand.

Quantitating Volatile Phenols in Cabernet Franc Berries and Wine after On-Vine Exposure to Smoke from a Simulated Forest Fire.

Smoke-taint is a wine defect linked to organoleptic volatile phenols (VPs) in Vitis vinifera L. berries that have been exposed to smoke from wildland fires. Herein, the levels of smoke-taint-associated VPs are reported in Cabernet Franc berries from veraison to commercial maturity and in wine after primary fermentation following on-vine exposure to simulated wildland fire smoke.

Quantitating Organoleptic Volatile Phenols in Smoke-Exposed Vitis vinifera Berries.

Accurate methods for quantitating volatile phenols (i.e., guaiacol, syringol, 4-ethylphenol, etc.

Nitenpyram degradation in finished drinking water.

Rationale: Neonicotinoid pesticides and their metabolites have been indicated as contributing factors in the decline of honey bee colonies. A thorough understanding of neonicotinoid toxicity requires knowledge of their metabolites and environmental breakdown products. This work investigated the rapid degradation of the neonicotinoid nitenpyram in finished drinking water.

Liquid chromatography-tandem mass spectrometry analysis of neonicotinoid pesticides and 6-chloronicotinic acid in environmental water with direct aqueous injection.

An efficient, high throughput and cost-effective direct aqueous injection approach for the analysis of neonicotinoid pesticides and a common metabolite in environmental water has been described here. The method determines eight neonicotinoid pesticides (acetamiprid, clothianidin, dinotefuran, flonicamid, imidacloprid, nitenpyram, thiacloprid, thiamethoxam) and 6-chloronicotinic acid (a common metabolite of the first generation neonicotinoids, acetamiprid, imidacloprid, nitenpyram and thiacloprid) without any sample enrichment/cleanup steps. The method detection limits are 2-8 ng/L for the neonicotinoids and 93 ng/L for 6-chloronicotinic acid.

Rapid characterization of naphthenic acids using differential mobility spectrometry and mass spectrometry.

To analyze the naphthenic acid content of environmental waters quickly and efficiently, we have developed a method that employs differential mobility spectrometry (DMS) coupled to mass spectrometry (MS). This technique combines the benefits of infusion-based MS experiments (parallel, on-demand access to individual components) with DMS's ability to provide liquid chromatography-like separations of isobaric and isomeric compounds in a fraction of the time. In this study, we have applied a DMS-MS workflow to the rapid gas-phase separation of naphthenic acids (NAs) within a technical standard and a real-world oil sands process-affected water (OSPW) extract.

Quantitative analysis of naphthenic acids in water by liquid chromatography-accurate mass time-of-flight mass spectrometry.

This study details the development of a routine method for quantitative analysis of oil sands naphthenic acids, which are a complex class of compounds found naturally and as contaminants in oil sands process waters from Alberta's Athabasca region. Expanding beyond classical naphthenic acids (CnH2n-zO2), those compounds conforming to the formula CnH2n-zOx (where 2≥x≤4) were examined in commercial naphthenic acid and environmental water samples. HPLC facilitated a five-fold reduction in ion suppression when compared to the more commonly used flow injection analysis.

Fast, extraction-free analysis of chlorinated phenols in well water by high-performance liquid chromatography-tandem mass spectrometry.

A fast and sensitive analytical method was developed for the chlorinated phenols included in the Canadian Drinking Water Guidelines without the need for costly, time-consuming sample extraction and concentration. Sensitivity and specificity were achieved by derivatization with dansyl chloride and detection via liquid chromatography-tandem mass spectrometry. The dansyl-modified analytes displayed method detection limits in the range of 0.

A quantitative kinetic study of polysorbate autoxidation: the role of unsaturated fatty acid ester substituents.

Purpose: To study the role of unsaturated fatty acid ester substituents in the autoxidation of polysorbate 80 using quantitative kinetics.

Methods: Oxidation kinetics were monitored at 40 degrees C in aqueous solution by tracking head space oxygen consumption using a fiber optic oxygen sensor with phase shift fluorescence detection. Radical chain initiation was controlled using an azo-initiator and assessed by Hammond's inhibitor approach, allowing oxidizability constants (k(p)/(2k(t))(1/2)) to be isolated.

Evaluation of chemical labeling strategies for monitoring HCV RNA using vibrational microscopy.

Raman and coherent anti-Stokes Raman scattering (CARS) microscopies have the potential to aid in detailed longitudinal studies of RNA localization. Here, we evaluate the use of carbon-deuterium and benzonitrile functional group labels as contrast agents for vibrational imaging of hepatitis C virus (HCV) replicon RNA. Dynamic light scattering and atomic force microscopy were used to evaluate the structural consequences of altering HCV subgenomic replicon RNA.

Synthesis and characterization of CN-modified protein analogues as potential vibrational contrast agents.

A recombinant VH single-domain antibody recognizing staphylococcal protein A was functionalized on reactive lysine residues with N-hydroxysuccimidyl-activated 4-cyanobenzoate. Surface plasmon resonance analysis of antibody-antigen binding revealed that modified and unmodified antibodies bound protein A with similar affinities. Raman imaging of the modified antibodies indicated that the benzonitrile group provides vibrational contrast enhancement in a region of the electromagnetic spectrum that is transparent to cellular materials.

Assessing antifreeze activity of AFGP 8 using domain recognition software.

Domain recognition software was employed to assess recrystallization-inhibition (RI) activity as an index of antifreeze potential. This represents a key step in the development of a high-throughput analysis for RI activity. Analysis of measurement error indicates an average coefficient of variation for individual crystals of about 8%, which is very small in relation to other sources of variation.

Peroxisome proliferator-activated receptor alpha antagonism inhibits hepatitis C virus replication.

Hepatitis C virus (HCV) is a global health problem and a leading cause of liver disease. Here, we demonstrate that the replication of HCV replicon RNA in Huh-7 cells is inhibited by a peroxisome proliferator-activated receptor (PPAR) antagonist, 2-chloro-5-nitro-N-(pyridyl)benzamide (BA). Downregulation of PPARgamma with RNA interference approaches had no effect on HCV replication in Huh-7 cells, whereas PPARalpha downregulation inhibited HCV replication.