Effect of harvest time on physicochemical quality parameters, oxidation stability, and volatile compounds of extra virgin olive oil

The aim of this study was to determine the changes in some physicochemical properties of olives (fruit weight, water content and oil content) and olive oils (total chlorophyll, carotenoid, pheophytin a, peroxide value and free acidity), and in the chemical properties (fatty acids, tocopherols, phenolics, oxidation stability and volatile profiles) of oils during ripening.Ripening indices (RI) of olive samples were 1.93 (unripe), 4.28 (ripe) and 5.89 (overripe). Most of the mentioned features changed with ripening. During ripening there was a sharp decrease in total chlorophyll, carotenoid and pheophytin a contents. An increase in oleic and linoleic acids and a decrease in palmitic acid were found in the fatty acid composition. Olive oils showed strong relations among oxidation stability, tocopherol content, total phenols content, and antiradical actvity of phenol extracts and these parameters decreased with maturation. Nevertheless, higher amounts of trans-2-hexenal were found in the oil from ripe olives than from unripe and overripe olives. On the other hand, the highest concentration of hexanal was found in the oil from overripe olives.In general, significant differences were observed in fruit weight, pigments, free acidity, fatty acid, tocopherol, and total phenolics contents, radical scavenger activity, oxidation stability, phenolic profile and volatile profile between the olive oils from the Gemlik cultivar at different stages of maturation

Evaluation and selection of indicators for land degradation and desertification monitoring : types of degradation, causes, and implications for management

International audienceIndicator-based approaches are often used to monitor land degradation and desertification from the global to the very local scale. However, there is still little agreement on which indicators may best reflect both status and trends of these phenomena. In this study, various processes of land degradation and desertification have been analyzed in 17 study sites around the world using a wide set of biophysical and socioeconomic indicators. The database described earlier in this issue by Kosmas and others (Environ Manage, 2013) for defining desertification risk was further analyzed to define the most important indicators related to the following degradation processes: water erosion in various land uses, tillage erosion, soil salinization, water stress, forest fires, and overgrazing.

The first record of the “Mid-Barremian” Oceanic Anoxic Event and the Late Hauterivian platform drowning of the Bilecik platform, Sakarya Zone, western Turkey

The late Hauterivian platform drowning has been recorded in the Hauterivian/Barremian boundary beds in western Turkey. This drowning event recorded by presence of hardgrounds, glauconite- and phosphate-bearing facies over the platform carbonates is followed up by pelagic carbonates

Photothermal and photodynamic responses of core-shell Mo₂C@C@Fucoidan nanospheres

Mo2C structure, a transition metal carbide, is known for its exceptional properties including high chemical and thermal stability and surface activity. Recently, carbon-modified Mo2C structures have found widespread applications due to their effectiveness. Here, we synthesized pomegranate-like Mo2C@C nanospheres and coated them with poly(allylamine hydrochloride) (PAH) and fucoidan structures. Characterization techniques including FE-SEM, HR-TEM, XRD, XPS, and zeta potential analysis were employed. We investigated the effect of Mo2C@C@Fuc nanospheres by quantitatively evaluating their photothermal conversion efficiency. Under irradiation at wavelengths of 808 nm and 1064 nm with a power intensity of 2 W/cm2, these nanospheres could convert up to 15 % of the incident laser energy into heat, outperforming conventional materials. Stability tests in various physiological pH environments confirmed their durability under NIR irradiation, ensuring operational integrity in biological environments. In addition, they showed significant efficiency in the production of singlet oxygen, making them promising agents for PDT. Biodegradation studies indicated safe degradation after therapeutic application, highlighting their environmental and physiological compatibility. Integrating Mo2C@C@Fuc nanospheres into anticancer strategies combines the advantages of PTT and PDT, promising improved therapeutic outcomes with high biocompatibility. © 2024Tarsus University; Ege University Institute of Nuclear Sciences; Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, TÜBİTAK, (122Z055); Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, TÜBİTA

I-based hybrid electrode

We experimentally demonstrate that oriented assembly of red algal photosystem I (PSI) reaction centers on a plasmonically active Silver Island Film (SIF) leads to strong enhancement of both the fluorescence intensity and photocurrent generated upon illumination. PSI complexes were specifically attached to a monolayer of graphene deposited on the SIF layer. The results of comprehensive fluorescence microscopy point to the critical role of the SIF layer in enhancing the optical response of PSI, as we observe increased emission intensity. Hence, importantly, the strong increase of photocurrent generation demonstrated for the biohybrid electrodes can be directly associated with the plasmonic enhancement of the optical and electrochemical functionalities of PSI. The results also indicate that the graphene layer is not diminishing the influence of the plasmonic excitations in SIF on the absorption and emission of PSI.C1 [Szalkowski, Marcin; Mackowski, Sebastian; Kowalska, Dorota] Nicolaus Copernicus Univ, Fac Phys Astron & Informat, Inst Phys, Grudziadzka 5, PL-87100 Torun, Poland.[Szalkowski, Marcin] Polish Acad Sci, Inst Low Temp & Struct Res, Okolna 2, PL-50422 Wroclaw, Poland.[Harputlu, Ersan; Ocakoglu, Kasim] Tarsus Univ, Fac Technol, Dept Energy Syst Engn, TR-33400 Tarsus, Turkey.[Kiliszek, Malgorzata; Kargul, Joanna] Univ Warsaw, Ctr New Technol, Solar Fuels Lab, Banacha 2C, PL-02097 Warsaw, Poland.[Unlu, C. Gokhan] Pamukkale Univ, Dept Biomed Engn, TR-20070 Denizli, Turkey