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The formation of a new fluorescence band of anthocyanidins and anthocyanidins, centered at about 530 nm (excitation at 460–470 nm), is proposed as a simple indicator of food oxidation. This fluorescence band appeared and increased progressively during the incubation of blueberry juice under aerobic conditions and the cooking of blueberry homogenate and black carrot. The same effect was observed upon the addition of delphinidin to rapeseed oil subjected to simulated frying. A ratiometric parameter (ratio of the fluorescence intensity at the maximum of the new band to the fluorescence intensity of native anthocyanins/anthocyanidin) is proposed as a versatile index useful for the estimation of the oxidation of food products containing anthocyanins or supplemented with anthocyanins or anthocyanidins.

In endothermic species, heat released as a product of metabolism ensures stable internal temperature throughout the organism, despite varying environmental conditions. Mitochondria are major actors in this thermogenic process. Part of the energy released by the oxidation of respiratory substrates drives ATP synthesis and metabolite transport, but a substantial proportion is released as heat. Using a temperature-sensitive fluorescent probe targeted to mitochondria, we measured mitochondrial temperature in situ under different physiological conditions. At a constant external temperature of 38 °C, mitochondria were more than 10 °C warmer when the respiratory chain (RC) was fully functional, both in human embryonic kidney (HEK) 293 cells and primary skin fibroblasts. This differential was abolished in cells depleted of mitochondrial DNA or treated with respiratory inhibitors but preserved or enhanced by expressing thermogenic enzymes, such as the alternative oxidase or the uncoupling protein 1. The activity of various RC enzymes was maximal at or slightly above 50 °C. In view of their potential consequences, these observations need to be further validated and explored by independent methods. Our study prompts a critical re-examination of the literature on mitochondria.

The ATP synthase of yeast mitochondria is composed of 17 different subunit polypeptides. We have screened a panel of ATP synthase mutants for impaired expression of Atp6p, Atp8p, and Atp9p, the only mitochondrially encoded subunits of ATP synthase. Our results show that translation of Atp6p and Atp8p is activated by F₁ ATPase (or assembly intermediates thereof). Mutants lacking the α or β subunits of F₁, or the Atp11p and Atp12p chaperones that promote F₁ assembly, have normal levels of the bicistronic ATP8/ATP6 mRNAs but fail to synthesize Atp6p and Atp8p. F₁ mutants are also unable to express ARG8m when this normally nuclear gene is substituted for ATP6 or ATP8 in mitochondrial DNA. Translational activation by F₁ is also supported by the ability of ATP22, an Atp6p-specific translation factor, to restore Atp6p and to a lesser degree Atp8p synthesis in the absence of F₁. These results establish a mechanism by which expression of ATP6 and ATP8 is translationally regulated by F₁ to achieve a balanced output of two compartmentally separated sets of ATP synthase genes.

A patient with late-onset exercise intolerance had haploinsufficiency of SLC25A32, which encodes the human mitochondrial flavin adenine dinucleotide transporter. The patient's symptoms were highly responsive to oral supplementation with riboflavin. To the Editor: Multiple acyl–coenzyme A dehydrogenation deficiency is an inborn error of metabolism with frequent muscle involvement. This deficiency is due to defects in the electron-transfer flavoprotein genes ETFA and ETFB 1 or in the electron-transfer flavoprotein ubiquinone oxidoreductase gene ETFDH . 2 In patients with this deficiency, all the mitochondrial flavoprotein dehydrogenases are defective with a specific biochemical phenotype for multiple acyl–coenzyme A dehydrogenation deficiency. Yet, in a few patients who have a deficiency that is similar to multiple acyl–coenzyme A dehydrogenation deficiency, no mutations are identified in ETFA, ETFB, or ETFDH . 3 We report on a 14-year-old girl who . . .

Cabbage is one of the most popular vegetables all over the world, with white cabbage generally being more popular than red cabbage. This study aimed at a comparison of the antioxidant properties of fresh and fermented white and red cabbage. Total phenolic content, the content of anthocyanins and carotenoids, and the Total Antioxidant Capacity (TAC) assayed by ABTS• scavenging, DPPH• scavenging, FRAP, and ORAC of fresh white and red cabbage, fermented white and red cabbage (sauerkraut), and sauerkraut juice were compared. The TAC of fresh and fermented red cabbage, and of red sauerkraut juice (110.3 ± 8.9, 47.4 ± 4.6 and 48.9 ± 5.7 mmol Trolox equivalents/kg, respectively) was significantly higher than the TAC of fresh and fermented white cabbage and white sauerkraut juice (5.1 ± 0.2, 7.9 ± 0.9 and 6.6 ± 0.9 mmol TE/kg, respectively, when assayed by ORAC). The TAC of white sauerkraut and white sauerkraut juice could be elevated by fermentation with 20% of black carrots (to 16.4 ± 1.2 and 10.5 ± 0.8 mmol TE/kg, respectively) but the TAC of red sauerkraut and red sauerkraut juice was diminished by a mixture of either orange or black carrots, which are of lower anthocyanin content than the red cabbage (41.8 ± 3.0 and 29.2 ± 3.1 mmol TE/kg, respectively). These results may justify the promotion of the broad consumption of red cabbage, both fresh and fermented, and encourage the usage of red cabbage as a promising material for functional foods.

N- and Fe-containing carbon-based materials were prepared at 600 and 700 °C via catalytic chemical vapor deposition (CCVD) with acetonitrile (as carbon and nitrogen source) with the application of metal/metal oxides generated in situ from Mg–Fe–Al hydrotalcite-like materials (HTs). The impact of synthesis temperature and transition metal (Fe) concentration in a blend of metal oxides derived from HTs on carbon deposit content and its structural ordering, nitrogen doping, location of N-containing groups in graphitic array, morphology and porosity was investigated using XRD, EA, XRF, XPS, SEM, HR-TEM, Raman and Mössbauer spectroscopy, and N 2 sorption. Higher synthesis temperature and increased concentration of Fe-containing species occurring in a mixture of metal oxides derived from Mg–Fe–Al HTs enhanced the quantity of carbonaceous product, the mesopore volume and the thickness of graphitic domains occurring in the carbon materials and lowered nitrogen doping extent in carbon framework. Enhanced accessibility to active sites via pore network, as well as, improved electrical conductivity associated with increased graphitic domain thickness and reduced amorphous carbon content were found to be critical factors in their performance for oxygen reduction reaction (ORR) in alkaline electrolyte. No direct correlation between the population of N-containing species and ORR activity is observed but the presence of quaternary N appears to enhance selectivity for the 4-electron pathway. In addition, the influence of the carbon materials dispersed in polymer matrix in polycaprolactone (PCL)-based composite films on bulk (conductivity, dielectric constant) and surface (morphology, topography, roughness and water contact angle) properties was also described. Graphical abstract

Human serum albumin (HSA) corona formation on polymer microparticles of a spheroidal shape was studied using dynamic light scattering and Laser Doppler Velocimetry (LDV). Physicochemical characteristics of the albumin comprising the zeta potential and the isoelectric point were determined as a function of pH for various ionic strengths. Analogous characteristics of the polymer particles were analyzed. The adsorption of albumin on the particles was in situ monitored by LDV. The stability of the HSA-functionalized particle suspensions under various pHs and their electrokinetic properties were also determined. The deposition kinetics of the particles on mica, silica and gold sensors were investigated by optical microscopy, AFM and quartz microbalance (QCM) under diffusion and flow conditions. The obtained results were interpreted in terms of the random sequential adsorption model that allowed to estimate the range of applicability of QCM for determining the deposition kinetics of viruses and bacteria at abiotic surfaces.

Cancer is a major and still increasing cause of death in humans. Most cancer cells have a fundamentally different metabolic profile from that of normal tissue. This shift away from mitochondrial ATP synthesis via oxidative phosphorylation towards a high rate of glycolysis, termed Warburg effect, has long been recognized as a paradigmatic hallmark of cancer, supporting the increased biosynthetic demands of tumor cells. Here we show that deletion of apoptosis-inducing factor (AIF) in a KrasG12D-driven mouse lung cancer model resulted in a marked survival advantage, with delayed tumor onset and decreased malignant progression. Mechanistically, Aif deletion leads to oxidative phosphorylation (OXPHOS) deficiency and a switch in cellular metabolism towards glycolysis in non-transformed pneumocytes and at early stages of tumor development. Paradoxically, although Aif-deficient cells exhibited a metabolic Warburg profile, this bioenergetic change resulted in a growth disadvantage of KrasG12D-driven as well as Kras wild-type lung cancer cells. Cell-autonomous re-expression of both wild-type and mutant AIF (displaying an intact mitochondrial, but abrogated apoptotic function) in Aif-knockout KrasG12D mice restored OXPHOS and reduced animal survival to the same level as AIF wild-type mice. In patients with non-small cell lung cancer, high AIF expression was associated with poor prognosis. These data show that AIF-regulated mitochondrial respiration and OXPHOS drive the progression of lung cancer.

Layered double hydroxides (LDHs) of various compositions, i.e. Mg–Al, Mg–Mn–Al, are applied as the precursors of metal oxides for the preparation of N-doped carbon materials via chemical vapour deposition (CVD) with acetonitrile (as carbon and nitrogen source) at 600 and 700 °C. The use of Mn-containing LDHs for the preparation of the carbon materials is a novelty. The impact of transition metal species, i.e. MnxOy, in a blend of metal oxides derived from LDHs on the amount of carbon deposit and its composition, morphology, textural and capacitive properties is investigated. Mn-containing species occurring in a mixture of metal oxides enhance the quantity of carbonaceous product compared to those derived from Mg–Al LDHs. Thermally heated Mg–Mn–Al LDHs contain structural defects due to manganese oxides, which promote the formation of carbon deposit, especially higher production of amorphous carbons. The addition of Mn into Mg–Al LDHs matrix leads to carbon particles with increased N-doping and enhanced volume of mesopores. Furthermore, graphitic domains occurring in the carbon materials obtained with Mg–Mn–Al LDHs are thicker than those in the corresponding samples obtained with Mg–Al LDHs as Mn-containing species influence the concentration and location of N-containing groups in graphitic array. The specific capacitance of the carbon materials produced by CVD with the compounds derived from Mg–Al LDHs or Mg–Mn–Al LDHs is comparable (20–25 μF cm−2). The formation of electrical double layer at electrode/electrolyte interface is easier for the carbon materials prepared at 700 °C than for the carbon materials prepared at 600 °C. The maximum charge is stored either in the shallow parts of carbon particles for the former, as they contain bottleneck mesopores, or in the deep parts of carbon particles for the latter, as they contain slit-shaped mesopores.

Succinate dehydrogenase (SDH) inhibitors (SDHIs) are used worldwide to limit the proliferation of molds on plants and plant products. However, as SDH, also known as respiratory chain (RC) complex II, is a universal component of mitochondria from living organisms, highly conserved through evolution, the specificity of these inhibitors toward fungi warrants investigation. We first establish that the human, honeybee, earthworm and fungal SDHs are all sensitive to the eight SDHIs tested, albeit with varying IC50 values, generally in the micromolar range. In addition to SDH, we observed that five of the SDHIs, mostly from the latest generation, inhibit the activity of RC complex III. Finally, we show that the provision of glucose ad libitum in the cell culture medium, while simultaneously providing sufficient ATP and reducing power for antioxidant enzymes through glycolysis, allows the growth of RC-deficient cells, fully masking the deleterious effect of SDHIs. As a result, when glutamine is the major carbon source, the presence of SDHIs leads to time-dependent cell death. This process is significantly accelerated in fibroblasts derived from patients with neurological or neurodegenerative diseases due to RC impairment (encephalopathy originating from a partial SDH defect) and/or hypersensitivity to oxidative insults (Friedreich ataxia, familial Alzheimer's disease).