Distribution of chlorophylls and carotenoids in ripening olives and between oil and alperujo when processed using a two-phase extraction system

The present work has studied the content and type of pigments present in olive fruits and the respective oils and alperujos. The concentration of isochromic pigment fractions—chlorophylls and carotenoids—decreased with fruit ripening, more markedly in the former than in the latter. This implied that the ratio between the two pigment fractions also decreased in parallel in the three products studied. However, the value in the oil was lower than in the fruit, and that in the alperujo was much higher. During the extraction process, the release of acids may have caused pheophytinization reactions in the chlorophyll fraction, increasing pheophytin content in alperujos and oils, whereas the carotenoid fraction was affected only in the alperujo. Chlorophyll b derivatives were destroyed in greater proportion than chlorophyll a derivatives during transfer to the oil. During processing the destruction of lutein was greater than that of β-carotene. The balance of matter between fruit, alperujo, and oil indicated that not all the fruit pigmentation was released from the structures, and most remained occluded in the alperujo. The rest of the pigmentation, and particularly the chlorophyll fraction, was partly destroyed during its transfer to the oil.     

Study of Ozonated Sunflower Oil Using 1H NMR and Microbiological Analysis

Prior studies have proven that ozonated vegetable oils present a high germicidal power. Ozonation of sunflower oil at different applied ozone dosage was carried out and peroxide and aldehydes indices along with antimicrobial activity were determined. The reaction products were identified using Proton Nuclear Magnetic Resonance Spectroscopy (¹H NMR). The principal signals intensity values were used for following the reaction course between ozone and sunflower oil. The reaction was following up to peroxide index values of 1202 mmol-equi/kg. The intensities of olefinic proton signals decreased with the gradual increase in ozone concentration but without disappearing completely. The Criegee ozonides obtained at 107.1 mg/g of ozone doses were approximately 3.9-fold higher than that at beginning of the reaction. The aldehyde protons were observed as a weak intensity signal in all the spectra. The signals belonging to olefinic protons from hydroperoxides appeared weak and increased with the increase in ozone doses. Signals from other oxygenated groups were assigned. The highest action spectrum of antimicrobial activity was obtained with the higher peroxide index. It was concluded that at higher applied ozone doses, the higher the antimicrobial activity potential of ozonized sunflower oil     

Optimization of Green Multiple Emulsions Processing to Improve Their Physical Stability

The effect of processing protocol on physical stability and the microstructure of water‐in‐oil‐in‐water multiple emulsions containing a mixture of two amphiphilic copolymers with opposed hydrophilic‐lipophilic balance as emulsifiers and a green solvent, 2‐ethylhexyl lactate, as the dispersed phase, has been assessed. Emulsions were obtained in at least two steps: a homogenization step by using a rotor‐stator device, followed by one or two homogenization steps carried out in a high‐pressure device that used microfluidizer technology. To study the microstructure and physical stability of these emulsions, a combination of different techniques, such as transmitted‐light optical microscopy, globule size distribution, viscous flow tests, and multiple light scattering measurements, were performed.     

Activated carbons as potentially useful non-nutritive additives to prevent the effect of fumonisin B1 on sodium bentonite activity against chronic aflatoxicosis

Aflatoxin B₁ (AFB₁) and fumonisin B₁ (FB₁) are mycotoxins that often co-occur in feedstuffs. The ingestion of AFB₁ causes aflatoxicosis in humans and animals. Sodium bentonite (NaB), a cheap non-nutritive unselective sequestering agent incorporated in animal diets, can effectively prevent aflatoxicosis. Fumonisins are responsible for equine leukoencephalomalacia and porcine pulmonary oedema, and often have subclinical toxic effects in poultries. Fumonisin B₁ and aflatoxin B₁ are both strongly adsorbed in vitro on sodium bentonite. Co-adsorption studies, carried out with a weight ratio of FB₁ to AFB₁ that mimics the natural occurrence (200:1), showed that FB₁ greatly decreases the in vitro ability of NaB to adsorb AFB₁. The ability of two activated carbons to adsorb FB₁ was also investigated. Both carbons showed high affinity for FB₁. A complex behaviour of the FB₁ adsorption isotherms with pH was observed. In vitro results suggest that under natural contamination levels of AFB₁ and FB₁, a mixture of activated carbon and sodium bentonite might be potentially useful for prevention of sub-acute aflatoxicosis.     

Simultaneous determination of neonicotinoid insecticides in sunflower-treated seeds (hull and kernel) by LC-MS/MS

A validated analytical method to determine seven neonicotinoids (dinotefuran, nitenpyram, thiamethoxam, clothianidin, imidacloprid, acetamiprid and thiacloprid) in sunflower seeds (hull and kernel) using HPLC coupled to electrospray ionisation mass spectrometry (ESI-MS) is presented. Sample clean-up based on a solid–liquid extraction, and the removal of lipid fraction, in the case of kernels, is proposed and optimised. Low limits of detection and quantification were obtained, ranging from 0.3 × 10^–3 to 1.2 × 10^–3 µg g^–1 and from 1.0 × 10^–3 to 4.0 × 10^–3 µg g^–1, with good precision, and recovery values ranged from 90% to 104% for hulls and kernels. The method was applied for the analysis of five thiamethoxam-dressed sunflower seeds and four non-treated seeds, where, besides thiamethoxam, residues of the other neonicotinoid, clothianidin, were also detected and confirmed via tandem mass spectrometry (LC-ESI-MS/MS). Finally, the presence of residues of thiamethoxam and clothianidin in collected sunflower seeds (hulls) coming from coated seeds confirmed the translocation of these neonicotinoids through the plant up to these seeds.     

Rheological Properties of Honey from Burkina Faso: Loss Modulus and Complex Viscosity Modeling

This study evaluated the rheological behavior of Burkina Faso honey and the use of exponential and polynomial models to predict the influence of chemical composition and temperature on the viscoelastic parameters: complex viscosity (η*) and loss modulus (G’’). Samples were first characterized by evaluating: water activity, 5-hydroxy methyl furfural, sugars (fructose, glucose, and sucrose), electrical conductivity, moisture, and color. Dynamic rheological properties were obtained at different temperatures (5, 10, 15, 20, 25, 30, and 40°C). All the honeys displayed Newtonian behavior. Complex viscosity and loss modulus can be predicted based on the chemical composition and temperature using polynomial models (R² > 98.00%).     

Physical and Antioxidant Characterization of Edible Films Added with Red Prickly Pear (<Emphasis Type="Italic">Opuntia ficus-indica</Emphasis> L.) cv. San Martín Peel and/or Its Aqueous Extracts

The aim of this research was to investigate the effect of the addition of peel powder and/or its aqueous extract on physical and antioxidant characteristics of carboxymethyl cellulose (CMC) edible films. Prickly pear peel powder and aqueous extract (2 and 4%) were characterized in color, bioactive compounds (betalains and total phenolic compounds), antioxidant capacity and reducing power. Edible films were prepared with CMC, glycerol, varying the dissolution medium (0, 2, or 4% aqueous extract from prickly pear peel) and peel powder (0, 1, or 2%) using a face-centered central composite design. Physical, mechanical, bioactive compounds, and antioxidant capacity properties were investigated in edible films. Prickly pear peel powder presented 58.8 ± 0.08 mg of betacyanins/100 g, 53.8 ± 0.2 mg of betaxanthins/100 g, 967.8 ± 20 mg Gallic acid equivalent (GAE)/100 g for total phenolic compounds, an antioxidant capacity equivalent to 420.9 ± 4.9 mg GAE/100 g and a reducing power of 879.1 ± 115.9 mg ascorbic acid equivalent (AAE)/100 g. High concentration of aqueous extract and peel powder in CMC films increased the bioactive compounds content, antioxidant capacity and reducing power. Films mechanical properties were not affected by the aqueous extract; nevertheless, were strongly affected by the peel powder. Response surface methodology was used to optimize edible films formulation with high antioxidant characteristics, being the optimal formulation 1.7% of peel powder plus 3.3% of aqueous extract. This study may be the base for exploitation of prickly pear peel as source of bioactive compounds with antioxidant capacity for their use in edible coatings.     

Veni,vidi, vici: the success of wtf meiotic drivers in fission yeast

Meiotic drivers are selfish DNA loci that can bias their own transmission into gametes. Owing to their transmission advantages, meiotic drivers can spread in populations even if the drivers or linked variants decrease organismal fitness. Meiotic drive was first formally described in the 1950s and is thought to be a powerful force shaping eukaryotic genomes. Classic genetic analyses have detected the action of meiotic drivers in plants, filamentous fungi, insects and vertebrates. Several of these drive systems have limited experimental tractability and relatively little is known about the molecular mechanisms of meiotic drive. Recently, however, meiotic drivers were discovered in a yeast species. The Schizosaccharomyces pombe wtf gene family contains several active meiotic drive genes. This review summarizes what is known about the wtf family and highlights its potential as a highly tractable experimental model for molecular and evolutionary characterization of meiotic drive.