Comparison of oxidation stability of virgin olive oils from different locations of Turkey

Ten kinds of virgin olive oil of two major cultivars (Ayvalık and Memecik) produced in several areas of Turkey (Bayındır, Edremit, Ortaklar, Burhaniye, Ezine, Tire, Havran, Ayvalık, Altınoluk, and Küçükkuyu) were analysed. The quality characteristics, fatty acid composition, total phenol, ando-diphenol content of the samples were determined. Oxidative stability and free radical scavenging activity were determined using Rancimat test, Schaal oven test, and DPPH method. It was found that while Memecik oil from Ortaklar demonstrated the strongest oxidative stability, Ayvalık oil from Ezine had the lowest oxidative stability among the samples. Fatty acid composition and especially oleic acid/linoleic acid ratio was previously defined as a parameter that can help distinguish cultivars from one another; however, this study proved that total phenol, especially o-diphenol content of the oil, has the strongest effect on oxidative stability compared to other factors including fatty acid composition

Interactions of invasive pumpkinseed with a riverine endemic fish indicate trophic overlap but minimal consequences for somatic growth and condition

The North American invasive fish pumpkinseed Lepomis gibbosus has been associated with some detrimental ecological consequences in some parts of its invasive range. Here, we tested the trophic interactions of pumpkinseed with the endemic stream fish Aegean chub Squalius fellowesii ('chub') in a Mediterranean-type water course in SW Anatolia, Turkey, using a bulk stable isotope approach (d13C, d15N). Seven sampling sites were able to be grouped as chub in pumpkinseed presence (n=2) and absence (n=3), and pumpkinseed in chub absence (n=2). Across these groups, stable isotope metrics revealed that chub trophic (isotopic) niche size was similar in pumpkinseed presence/absence, but pumpkinseed had a larger niche in chub presence. In sites where they are co-habited, their niches showed some convergence, but with no apparent consequences for their growth or body condition, suggesting there were minimal ecological consequences of this sharing of food resources. These results suggest that the trophic consequences of this riverine invasion of pumpkinseed on this endemic chub was minimal

Development of validated stability-indicating chromatographic method for the determination of fexofenadine hydrochloride and its related impurities in pharmaceutical tablets

A simple reversed phase high performance liquid chromatographic method with diode array detector (HPLC-DAD) has been developed and subsequently validated for the determination of fexofenadine hydrochloride (FEX) and its related compounds; keto fexofenadine (Impurity A), meta isomer of fexofenadine (Impurity B), methyl ester of fexofenadine (Impurity C) in addition to the methyl ester of ketofexofenadine (Impurity D). The separation was based on the use of a Hypersil BDS C-18 analytical column (250 × 4.6 mm, i.d., 5 μm). The mobile phase consisted of a mixture of phosphate buffer containing 0.1 gm% of 1-octane sulphonic acid sodium salt monohydrate and 1% (v/v) of triethylamine, pH 2.7 and methanol (60:40, v/v). The separation was carried out at ambient temperature with a flow rate of 1.5 ml/min. Quantitation was achieved with UV detection at 215 nm using lisinopril as internal standard, with linear calibration curves at concentration ranges 0.1-50 μg/ml for FEX and its related compounds. The optimized conditions were used to develop a stability-indicating HPLC-DAD method for the quantitative determination of FEX and its related compounds in tablet dosage forms. The drugs were subjected to oxidation, hydrolysis, photolysis and heat to apply stress conditions. Complete separation was achieved for the parent compounds and all degradation products. The method was validated according to ICH guidelines in terms of accuracy, precision, robustness, limits of detection and quantitation and other aspects of analytical validation

Geohistorical insights into marine functional connectivity

Marine functional connectivity (MFC) refers to the flows of organic matter, genes, and energy that are caused by the active and passive movements of marine organisms. Occurring at various temporal and spatial scales, MFC is a dynamic, constantly evolving global ecological process, part of overall ecological connectivity, but with its own distinct and specific patterns. Geological and historical archives of changes in the distributions, life histories, and migration of species can provide baselines for deciphering the long-term trends (decadal to millions of years) and variability of MFC. In this food-for-thought paper, we identify the different types of geohistorical data that can be used to study past MFC. We propose resources that are available for such work. Finally, we offer a roadmap outlining the most appropriate approaches for analysing and interpreting these data, the biases and limitations involved, and what we consider to be the primary themes for future research in this field. Overall, we demonstrate how, despite differences in norms and limitations between disciplines, valuable data on ecological and societal change can be extracted from geological and historical archives, and be used to understand changes of MFC through time