Upregulation of Skin-Aging Biomarkers in Aged NHDF Cells by a Sucrose Ester Extract from the Agroindustrial Waste of Physalis peruviana Calyces.

As part of a search for new sustainable plant sources of valuable compounds, the EtOAc extract of the discarded calyces of Physalis peruviana fruit was selected for its significant antiaging activity. Eight new sucrose esters (SEs), named peruvioses F-M (1-8), along with three known SEs, peruvioses A (9), peruviose B (10), and nicandrose D (11), were isolated. Their structures were elucidated by comprehensive analyses of their NMR and MS data. A global fragmentation pattern of these SEs was established from their MS data. The SE extract (SEE) at a concentration of 0.5 mg L-1 upregulated multiple skin-aging biomarkers, namely, collagen I, elastin, and fibrillin-1, in aged normal human dermal fibroblast cells. A 36% increase in collagen I was observed. The elastin and fibrillin-1 contents were fully recovered, and an increase of at least 10% in the production of elastin was observed.

Quantification of Hydrogen Sulfide and Methanethiol and the Study of Their Scavenging by Biocides of the Isothiazolone Family.

A sensitive analytical method for the quantification of malodourous hydrogen sulfide (H2 S) and methanethiol (CH3 SH) was developed and validated. The method consisted of solid-phase microextraction with concomitant in-fibre derivatisation of the mercaptan using N-ethylmaleimide. The adducts were analysed by GC-MS using a triple quadrupole in the selected reaction monitoring mode. The limits of detection of solutions of H2 S and CH3 SH in water were 100 and 10 ng L-1 , respectively, below their odour-perception thresholds. The analytical method was used to show the scavenging effect of 1,2-benzisothiazol-3(2H)-one (Proxel) and 2-methyl-4-isothiazolinone. The mechanism by which H2 S and CH3 SH are trapped with Proxel was studied by ultraperformance liquid chromatography (UPLC)-MS.

Collaborative validation of the quantification method for suspected allergens and test of an automated data treatment.

Previous publications investigated different data treatment strategies for quantification of volatile suspected allergens by GC/MS. This publication presents the validation results obtained on "ready to inject" samples under reproducibility conditions following inter-laboratory ring-testing. The approach is based on the monitoring of three selected ions per analyte using two different GC capillary columns. To aid the analysts a decisional tree is used for guidance during the interpretation of the analytical results. The method is evaluated using a fragrance oil concentrate spiked with all suspected allergens to mimic the difficulty of a real sample extract or perfume oil. At the concentrations of 10 and 100mg/kg, imposed by Directive 76/768/EEC for labeling of leave-on and rinse-off cosmetics, the mean bias is +14% and -4%, respectively. The method is linear for all analytes, and the prediction intervals for each analyte have been determined. To speed up the analyst's task, an automated data treatment is also proposed. The method mean bias is slightly shifted towards negative values, but the method prediction intervals are close to that resulting from the decisional tree.

Quantification in Gas Chromatography: Prediction of Flame Ionization Detector Response Factors from Combustion Enthalpies and Molecular Structures.

In a previous report, we validated the use of a database that compiled the relative response factors of flavor and fragrance compounds under standard GC conditions for a flame ionization detector. Here we investigate the prediction of unknown response factors from the molecular structure by using combustion enthalpies. In a first step, this enthalpy was well-predicted with either ab initio calculation or multiple linear regression based on the molecular formula. In a second step, good correlation was observed between these combustion enthalpies and experimental relative response factors, and so the response factors were predictable from only the molecular formula. With a database of 351 compounds, about 60% of them exhibited a difference of less than 5% between the predicted and experimental relative response factors and about 80% exhibited a difference of less than 10%.

Quantification in gas chromatography: prediction of flame ionization detector response factors from combustion enthalpies and molecular structures.

In a previous report, we validated the use of a database that compiled the relative response factors of flavor and fragrance compounds under standard GC conditions for a flame ionization detector. Here we investigate the prediction of unknown response factors from the molecular structure by using combustion enthalpies. In a first step, this enthalpy was well-predicted with either ab initio calculation or multiple linear regression based on the molecular formula. In a second step, good correlation was observed between these combustion enthalpies and experimental relative response factors, and so the response factors were predictable from only the molecular formula. With a database of 351 compounds, about 60% of them exhibited a difference of less than 5% between the predicted and experimental relative response factors and about 80% exhibited a difference of less than 10%.

Quantitation of the main constituents of vanilla by reverse phase HPLC and ultra-high-pressure-liquid-chromatography with UV detection: method validation and performance comparison.

Vanilla's main constituents, i. e., vanillin, para-hydroxybenzaldehyde, and their corresponding acids, can be easily quantified by RP LC with UV detection and external calibration. This paper describes two methods that were developed using HPLC and ultra-high-pressure LC (UHPLC), respectively, and validated according to the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH). Both methods were highly specific, exhibited good linearities with high precision, and achieved good accuracies of quantitative results. The UHPLC method was more sensitive, five times shorter, and gave better peak resolutions than the HPLC alternative.

Comparison of extraction techniques and modeling of accelerated solvent extraction for the authentication of natural vanilla flavors.

Accelerated solvent extraction (ASE) of vanilla beans has been optimized using ethanol as a solvent. A theoretical model is proposed to account for this multistep extraction. This allows the determination, for the first time, of the total amount of analytes initially present in the beans and thus the calculation of recoveries using ASE or any other extraction technique. As a result, ASE and Soxhlet extractions have been determined to be efficient methods, whereas recoveries are modest for maceration techniques and depend on the solvent used. Because industrial extracts are obtained by many different procedures, including maceration in various solvents, authenticating vanilla extracts using quantitative ratios between the amounts of vanilla flavor constituents appears to be unreliable. When authentication techniques based on isotopic ratios are used, ASE is a valid sample preparation technique because it does not induce isotopic fractionation.