A new facile and fast method was developed in this study for the determination of pigments (chlorophylls and carotenoids), tocopherols (α-, sum of (β + γ), and δ), and squalene in olive oil. This method consisted of a dilution of olive oil in 2-propanol, followed by reversed phase-high-pressure liquid chromatography equipped with a diode array detector (RP-HPLC-DAD). Chromatographic separation was performed using a C18 column, while the mobile phase consisted of acetonitrile and methanol using a gradient elution program. The methodology was optimized, validated, and applied to the analysis of 452 samples of Extra Virgin Olive Oil (EVOOs) and Virgin Olive Oil (VOOs) originated from five islands of the Northeastern Aegean Region, in Greece. From the obtained results, it was indicated that the carotenoid, tocopherol, and squalene content was relatively high, while the chlorophyll content was low. Furthermore, the acquired results were studied and compared in order to obtain useful information about the correlation of the concentration levels of these compounds in olive oil to different cultivation and olive oil production parameters. Several parameters were found to play a significant role on the pigment and antioxidant content of olive oil, such as the olive tree variety, geographical origin, fruit maturation stage during harvesting, and addition of water during malaxation, while other parameters such as the altitude of cultivation, the type of farming (organic or conventional), and the type of olive mill did not seem to affect the levels of these compounds.

The ongoing pandemic caused by the emergence of SARS-CoV-2 has resulted in millions of deaths worldwide despite the various measures announced by the authorities. Wastewater-based epidemiology has the ability to provide a day-to-day estimation of the number of infected people in a fast and cost-effective manner. However, owing to the complex nature of wastewater, wastewater monitoring for viral genome copies is affected by the extensive viral fragmentation that takes place all the way to the sewage and the analytical lab. The aim of this study was to evaluate different methodologies for the concentration and extraction of viruses in wastewaters and to select and improve an option that maximizes the recovery of SARS-CoV-2. We compare 5 different concentration methods and 4 commercially available kits for the RNA extraction. To evaluate the performance and the recovery of these, SARS-CoV-2 isolated from patients was used as a spike control. Additionally, the presence of SARS-CoV-2 in all wastewater samples was determined using reverse transcription quantitative PCR (RT-qPCR) and reverse transcription droplet digital PCR (RT-ddPCR), targeting three genetic markers (N1, N2 and N3). Using spiked samples, recoveries were estimated 2.1–37.6% using different extraction kits and 0.1–2.1% using different concentration kits. It was found that a direct capture-based method, evaluated against a variety of concentration methods, is the best in terms of recovery, time and cost. Interestingly, we noticed a good agreement between the results provided by RT-qPCR and RT-ddPCR in terms of recovery. This evaluation can serve as a guide for laboratories establishing a protocol to perform wastewater monitoring of SARS-CoV-2. Overall, data presented here reinforces the validity of WBE for SARS-CoV-2 surveillance, uncovers potential caveats in the selection of concentration and extraction protocols and points towards optimal solutions to maximize its potential.

Two liquid chromatographic systems, one coupled to atmospheric pressure chemical ionization and tandem mass spectrometric methods (UHPLC-APCI-MS/MS) and the other a high-performance liquid chromatographic coupled to diode array detector (HPLC-DAD) were used to develop and validate methods for the simultaneous determination of fat-soluble vitamins A, D3 and E in rice cereal baby foods. The chromatographic separation was performed on C18 columns with a mixture of methanol-acetonitrile as mobile phase for all methods. The extraction of fat-soluble vitamins included enzymatic hydrolysis with α-amylase, saponification, extraction with petroleum ether or n-hexane and purification with silica cartridge (only for vitamin D3). Quantification of vitamin D3 and E through UHPLC-APCI-MS/MS was performed by the use of internal standards (IS) D3-d3 and E-d6, respectively, while IS was not used for vitamin A. The methods were optimized and validated in terms of linearity, precision, trueness, limits of detection and quantification. The recoveries were in the range of 85.0–107% for retinol, 92.0–105% for α-tocopherol and 95.2–106% for cholecalciferol and the %RSD (Relative Standard Deviation) values ranged from 6.4% to 15%. The evaluation of the methods was also conducted through the estimation of uncertainties, the application in commercial samples and the participation in a proficiency test