Effect of Polyethylene Glycol Treatment on Acetic Acid Emissions from Wood

Acetic acid is known to be emitted from sound wood and can accelerate damage to heritage materials, particularly metals. However, few studies have investigated the extent of acetic acid emissions from archaeological wood. This research utilised Solid-Phase-Micro-Extraction (SPME) GC–MS and lead coupon corrosion to identify volatile emissions from polyethylene glycol (PEG)-treated archaeological wood from the Mary Rose collection and assess if they could cause accelerated damage. In addition, the effect of PEG treatment on acetic acid emissions was investigated using sound wood samples. For sound wood, the PEG treatment acted as a barrier to acetic acid emissions, with higher-molecular-weight PEGs preventing more emissions. Archaeological wood, despite its age and high-molecular-weight PEG treatment, still emitted detectable concentrations of acetic acid. Moreover, they emitted a wider array of compounds compared to sound wood, including carbon disulphide. Like sound wood, when the archaeological wood samples were in a sealed environment with lead coupons, they caused accelerated corrosion to lead. This evidences that archaeological wood can emit high enough concentrations of volatile compounds to cause damage and further investigation should be performed to evaluate if this can occur inside museum display cases.

Phytochemicals and Volatiles in Developing Pelargonium ‘Endsleigh’ Flowers

Rose-scented geranium (Pelargonium sp.) have been the subject of many studies concerning essential oil, unlike the edible flowers of scent Pelargonium despite the beneficial properties of chemical compounds present in such organ and the fragrances produced. Therefore, we investigated organic compounds, total phenols and the antioxidant activity of the flowers with particular attention to the volatile compounds emitted by flowers of Pelargonium ‘Endsleigh’ at three stages of development. We identified several major phenols and organic compounds that revealed significative difference compared with other Pelargonium flowers, and employing the solid-phase micro extraction (SPME) methodology we determined that the production of volatile compounds decreases during the flower development. In addition, the emission of volatiles is accomplished mainly by the sepals. In conclusion, to use Pelargonium ‘Endsleigh’ flowers, it is important in ensuring that they have not yet opened and that the sepals are in place.

Characteristic-Aroma-Component-Based Evaluation and Classification of Strawberry Varieties by Aroma Type

The unique fruity aroma of strawberries, a popular fruit of high economic value, is closely related to all the volatile organic compounds (VOCs) contained within them. Despite extensive studies on the identification of VOCs in strawberries, systematic studies on fruit-aroma-related VOCs are few, resulting in a lack of effective standards for accurately distinguishing aroma types. In the present study, solid-phase micro extraction and gas chromatography–mass spectrometry were used to analyze and identify VOCs in the ripe fruit of each of the 16 strawberry varieties at home and abroad and to explore their characteristic aroma components and the classification of such varieties by aroma type. The results suggested remarkable variations in the types and contents of VOCs in different strawberry varieties, of which esters were dominant. The principal volatile components, consisting of four esters, three alcohols, one aldehyde, and one ketone, in 16 strawberry varieties were detected based on the absolute and relative contents of VOCs in the fruit. The characteristic aroma components in strawberries, containing nine esters, six aldehydes, and one alcohol, were determined based on the aroma values of different VOCs, and the characteristic aroma components were divided into five types further based on aroma descriptions. Sixteen strawberry varieties were finally divided into four aroma types, namely, peachy, pineapple, fruity, and floral, based on the contributions of different types. The results provided a basis and standard for classifying strawberries by aroma type, studying the hereditary regularity of the fruity aroma of strawberries, and improving aroma quality.

Development of a Headspace-Solid Phase Micro Extraction Method for the Analysis of Volatile and Semi-Volatile Organic Compounds from Polyurethane Resins for Leather Finishing

Volatile organic compounds (VOCs) and Semi-Volatile Organic Compounds (SVOCs) arise from the chemicals used in the various stages of the leather manufacturing process. An important aim of the tanning industry is to minimize or eliminate VOCs and SVOCs, without lowering the quality of leather. This paper shows the development of a new headspace-solid phase micro extraction coupled with gas chromatography–mass spectrometry (HS-SPME/GC-MS) method for the identification of VOCs and SVOCs emitted by newly designed polymers for the leather finishing operation. These new polymers are polyurethane resins designed to reduce the VOC and SVOC concentration. This method enables a simple and fast determination of the qualitative and semi-quantitative content of VOCs and SVOCs in polyurethane-type finishing resins. The chemicals that are of concern in this paper are the following: Dipropylene glycol Monomethyl Ether (DPGME), DBE-3 (a mixture of dibasic esters) and Triethylamine (TEA). The test conditions that have been determined to carry out the HS-SPME assay are the following: incubation time (2 hours), extraction temperature and time (40°C; 5 minutes) and the desorption conditions (280°C, 50 seconds). Ten samples of laboratory scale resins were tested by HS-SPME followed by gas chromatography (GC-MS). DPGME and DBE-3 (a mixture of dimethyl adipate, dimethyl glutarate and dimethyl succinate) have been identified effectively. The compounds are identified by a quantitative method using external calibration curves for the target compounds. The technique is not effective to determine the TEA compound, since the chromatograms shown poor resolution peaks for the standard.

Terpene Compounds of New Tunisian Extra-Virgin Olive Oil: Effect of Ripening Stage

The volatile profiles of Tunisian virgin olive oils were established by solid phase micro-extraction (SPME) and gas chromatography (GC), using flame ionisation and mass spectrometer detectors. Terpenes compounds were identified and characterized. Limonene, the main terpene compound extracted by SPME, characterized the studied olive oil. Significant differences in the proportions of terpenes constituents from oils of different maturity index were detected. The results demonstrated that the accumulation of the terpenes compounds in the studied oils obtained from different ripeness stage was strictly connected with the ripeness stage.

Evaluation and determination of occupational and environmental exposure of lead in workplace air and human workers based dispersive ionic liquid solid phase micro extraction in battery manufacturing factories from Iran

The exposure of lead in workplace air and human workers of battery manufacturing factory was evaluated determined by nanotechnology since 2019-2020. Human whole blood (HWB) for subject and healthy peoples (25-55, Men, 40 N) and workplace air (40N) was prepared based on NIOSH sampling. 10 mL of HWB samples added to 20 mg of mixture ionic liquid/ ligand ([HMIM][PF6]/APDC) modified on graphene oxide nanostructures(GONs) at pH=6. After sonication, the lead ions separated/extracted by dispersive ionic liquid solid phase micro extraction (DIL-SPME) and determined by flame atomic absorption spectrometry (F-AAS). All air samples in workplace were analyzed based on NIOSH process. The results showed us the negative correlation between Pb concentration in human blood subject and healthy peoples (r=0.24). The range concentrations of lead in human subject, healthy peoples and workplace air were obtained 193.4-543.7 µg L-1, 85.6-175.9 µgL-1 and 44.7-81.5 µgm-3, respectively. The LOD, linear rang, enrichment factor(EF) and RSD% were achieved 1.25 µg L-1, 5.0- 310 µg L-1, 19.6 and less than 5% by procedure. The method was validated by standard reference material (SRM), the electrothermal atomic absorption spectrometry (ET-AAS) and ICP-MS analyzer for human samples.