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Plasmalogens are glycerophospholipids with a vinyl ether linkage at the sn-1 position of the glycerol backbone. Despite being suggested as antioxidants due to the high reactivity of their vinyl ether groups with reactive oxygen species, our study reveals the generation of subsequent reactive oxygen and electrophilic lipid species from oxidized plasmalogen intermediates. By conducting a comprehensive analysis of the oxidation products by liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS), we demonstrate that singlet molecular oxygen [O2 (1Δg)] reacts with the vinyl ether bond, producing hydroperoxyacetal as a major primary product (97%) together with minor quantities of dioxetane (3%). Furthermore, we show that these primary oxidized intermediates are capable of further generating reactive species including excited triplet carbonyls and O2 (1Δg) as well as electrophilic phospholipid and fatty aldehyde species as secondary reaction products. The generation of excited triplet carbonyls from dioxetane thermal decomposition was confirmed by light emission measurements in the visible region using dibromoanthracene as a triplet enhancer. Moreover, O2 (1Δg) generation from dioxetane and hydroperoxyacetal was evidenced by detection of near-infrared light emission at 1,270 nm and chemical trapping experiments. Additionally, we have thoroughly characterized alpha-beta unsaturated phospholipid and fatty aldehydes by LC-HRMS analysis using two probes that specifically react with aldehydes and alpha-beta unsaturated carbonyls. Overall, our findings demonstrate the generation of excited molecules and electrophilic lipid species from oxidized plasmalogen species unveiling the potential prooxidant nature of plasmalogen-oxidized products.

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The presence of pathogenic bacteria in food is considered as a primary cause of food-borne illness and food quality deterioration worldwide. The present study aimed to determine the effectiveness of five essential oils (EOs) against multidrug-resistant foodborne pathogens. In the current study Gram-negative bacteria (Escherichia, Enterobacter, Citrobacter, Proteus, Pseudomonas, and Klebsiella) and the Gram-positive bacteria Staphylococcus were isolated from raw milk and biochemically characterized. The anti-bacterial effect of different antibiotics and EOs (thyme, oregano, lemongrass, mint, and rosemary) was determined using the standard disc diffusion method. The antibiogram study revealed that Gram-negative bacteria were highly resistant to penicillin while Staphylococcus was resistant to streptomycin, amoxicillin, and lincomycin. Moderate resistance was observed to doxycycline, amikacin, enrofloxacin, kanamycin and cefixime. Isolates were found less resistant to gentamycin, chloramphenicol, and ciprofloxacin. EOs showed a broad range of antimicrobial activity against all bacteria except P. aeruginosa. Of these, thyme was more effective against most of the multi-drug resistant bacterial strains and formed the largest zone of inhibition (26 mm) against Escherichia followed by oregano oil (18 mm) against Staphylococcus (p<0.05). Klebsiella spp and Citrobacter spp showed resistance to mint and lemongrass oil respectively. The EOs such as lemongrass, mint and rosemary were less active against all the bacteria. The findings of the recent study suggest the use of EOs as natural antibacterial agents for food preservation.

A presença de bactérias patogênicas em alimentos é considerada a principal causa de doenças transmitidas por alimentos e deterioração da qualidade dos alimentos em todo o mundo. O presente estudo teve como objetivo determinar a eficácia de cinco óleos essenciais (OEs) contra patógenos de origem alimentar multirresistentes. No presente estudo, bactérias Gram-negativas (Escherichia, Enterobacter, Citrobacter, Proteus, Pseudomonas e Klebsiella) e as bactérias Gram-positivas Staphylococcus foram isoladas do leite cru e caracterizadas bioquimicamente. O efeito antibacteriano de diferentes antibióticos e OEs (tomilho, orégano, capim-limão, hortelã e alecrim) foi determinado usando o método padrão de difusão em disco. O estudo do antibiograma revelou que as bactérias Gram-negativas eram altamente resistentes à penicilina, enquanto o Staphylococcus era resistente à estreptomicina, amoxicilina e lincomicina. Foi observada resistência moderada à doxiciclina, amicacina, enrofloxacina, canamicina e cefixima. Os isolados foram encontrados menos resistentes à gentamicina, cloranfenicol e ciprofloxacina. Os OEs mostraram uma ampla gama de atividade antimicrobiana contra todas as bactérias, exceto P. aeruginosa. Destes, o tomilho foi mais eficaz contra a maioria das cepas bacterianas multirresistentes e formou a maior zona de inibição (26 mm) contra Escherichia seguido de óleo de orégano (18 mm) contra Staphylococcus (p<0,05). Klebsiella spp e Citrobacter spp apresentaram resistência ao óleo de menta e capim-limão, respectivamente. Os OEs como capim-limão, hortelã e alecrim foram menos ativos contra todas as bactérias. Os resultados do estudo recente sugerem o uso de OEs como agentes antibacterianos naturais para conservação de alimentos.

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The performance of mechanochemically synthesized supported bimetallic AgAu nanoalloy catalysts was evaluated in the oxidative cleavage of methyl oleate, a commonly available unsaturated bio-derived raw material. An extensive screening of supports (SiO2 , C, ZrO2 , Al2 O3 ), metallic ratios (Ag : Au), reaction times, temperatures, and use of solvents was carried out. The performance was optimized towards productivity and selectivity for the primary cleavage products (aldehydes and oxoesters). The optimal conditions were achieved in the absence of solvent, using Ag8 Au92 /SiO2 as catalyst, at 80 °C, reaction time of 1 h, substrate to catalyst=555 and 10 bar of molecular oxygen. A strong support effect was observed: the selectivity to aldehydes was best with silica as support, and to esters was best using zirconia. This shows not only that mechanochemical preparation of bimetallic catalysts is a powerful tool to generate useful catalyst compositions, but also that a safe, green, solventless synthesis of bio-derived products can be achieved by aerobic oxidative cleavage.

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Aldehyde dehydrogenase 2 (ALDH2) is a mitochondrial enzyme involved in reactive aldehyde detoxification. Approximately 560 million people (about 8% of the world's population) carry a point mutation in the aldehyde dehydrogenase 2 gene (ALDH2), identified as ALDH2*2, which leads to decreased ALDH2 catalytic activity. ALDH2*2 variant is associated with an accumulation of toxic reactive aldehydes and consequent disruption of cellular metabolism, which contributes to the establishment and progression of several degenerative diseases. Consequences of aldehyde accumulation include impaired mitochondrial functional, hindered anabolic signaling in the skeletal muscle, impaired cardiovascular and pulmonary function, and reduced osteoblastogenesis. Considering that aldehydes are endogenously produced through redox processes, it is expected that conditions that have a high energy demand, such as exercise, might be affected by impaired aldehyde clearance in ALDH2*2 individuals. Despite the large body of evidence supporting the importance of ALDH2 to ethanol metabolism, redox homeostasis and overall health, specific research investigating the impact of ALDH2*2 on phenotypes relevant to exercise performance are notoriously scarce. In this commentary, we highlight the consolidated knowledge on the impact of ALDH2*2 on physiological processes that are relevant to exercise.

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Aldehydes, particularly acetaldehyde, are carcinogenic molecules and their concentrations in foodstuffs should be controlled to avoid upper aerodigestive tract (UADT) and liver cancers. Highly reactive, acetaldehyde forms DNA and protein adducts, impairing physiological functions and leading to the development of pathological conditions. The consumption of aged beer, outside of the ethanol metabolism, exposes habitual drinkers to this carcinogen, whose concentrations can be over-increased due to post-brewing chemical and biochemical reactions. Storage-related changes are a challenge faced by the brewing industry, impacting volatile compound formation and triggering flavor instability. Aldehydes are among the volatile compounds formed during beer aging, recognized as off-flavor compounds. To track and understand aldehyde formation through multiple pathways during beer storage, consequent changes in flavor but particularly quality losses and harmful compound formation, this systematic review reunited data on volatile compound profiles through gas chromatography analyses from 2011 to 2021. Conditions to avoid flavor instability and successful methods for reducing beer staling, and consequent acetaldehyde accumulation, were raised by exploring the dynamic conversion between free and bound-state aldehydes. Future research should focus on implementing sensory analyses to investigate whether adding aldehyde-binding agents, e.g., cysteine and bisulfite, would contribute to consumer acceptance, restore beer flavor, and minimize acetaldehyde-related health damage.

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It is well established that lipid aldehydes (LAs) are able to increase the permeability of cell membranes and induce their rupture. However, it is not yet clear how LAs are distributed in phase-separated membranes (PSMs), which are responsible for the transport of selected molecules and intracellular signaling. Thus, we investigate here the distribution of LAs in a PSM by coarse-grained molecular dynamics simulations. Our results reveal that LAs derived from mono-unsaturated lipids tend to accumulate at the interface between the liquid-ordered/liquid-disordered domains, whereas those derived from poly-unsaturated lipids remain in the liquid-disordered domain. These results are important for understanding the effects caused by oxidized lipids in membrane structure, properties and organization.

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Hydrogen peroxide (H2O2) has been shown to efficiently remove toxic microalgae from enclosed ballast waters and brackish lakes. In this study, in vitro experiments were conducted to assess the side effects of mitigating toxic and non-toxic dinoflagellates with H2O2. Five H2O2 concentrations (50 to 1000 ppm) were used to control the cell abundances of the toxic dinoflagellates Alexandrium catenella and Karenia selliformis and the non-toxic dinoflagellates Lepidodinium chlorophorum and Prorocentrum micans. Photosynthetic efficiency and staining dye measurements showed the high efficiency of H2O2 for mitigating all dinoflagellate species at only 50 ppm. In a bioassay carried out to test cytotoxicity using the cell line RTgill-W1, control experiments (only H2O2) showed cytotoxicity in a concentration- and time- (0 to 24 h) dependent manner. The toxic dinoflagellates, especially K. selliformis, showed basal cytotoxicity that increased with the application of hydrogen peroxide. Unexpectedly, the application of a low H2O2 concentration increased toxicity, even when mitigating non-toxic dinoflagellates. This study suggests that the fatty acid composition of toxic and non-toxic dinoflagellate species can yield toxic aldehyde cocktails after lipoperoxidation with H2O2 that can persist in water for days with different half-lives. Further studies are needed to understand the role of lipoperoxidation products as acute mediators of disease and death in aquatic environments.

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Ethoxycarbonyl cyanohydrins and O-acyl cyanohydrins are examples of O-protected cyanohydrins in which the protecting group presents an electrophilic center, contributing to additional reaction pathways. The first section of this review describes recent advances on the synthesis of O-ethoxycarbonyl and O-acyl protected cyanohydrins. Reactions using KCN or alkyl cyanoformates as the cyanide ion source are described, as well as organic and transition metal catalysis used in their preparation, including asymmetric cyanation. In a second part, transformations, and synthetic applications of O-ethoxycarbonyl/acyl cyanohydrins are presented. A variety of structures has been obtained starting from such protected cyanohydrins and, in particular, the synthesis of oxazoles, 1,4-diketones, 1,3-diketones, 2-vinyl-2-cyclopentenones through various methods are discussed.

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Methoximes are important as a class of intermediates and products, among fine chemicals and specialties. The development of a new, facile and efficient method for their synthesis is reported. The methoximes were properly accessed from the corresponding aromatic aldehydes and ketones in good to excellent yields, under mild conditions, employing the inexpensive and environmentally friendly MnCl2.4H2O as a catalyst (at low loading and without the addition of ligand), in EtOH at 50°C. The scope of the process was systematically assessed.

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The recent developments on fieldable miniature mass spectrometers require efforts to produce easy-to-use and portable alternative tools to assist in point-of-care analysis. In this paper, the reagent-pencil (RP) technology, which has been used for solvent-free deposition of reagents in paper-based microfluidics, was combined with paper spray ionization mass spectrometry (PS-MS). In this approach, named RP-PS-MS, the PS triangular piece of paper was written with the reagent pencil, consisting of mixtures of graphite and bentonite (used as a support) and a reactive compound, and allowed to react with a given analyte from a sample matrix selectively. We conducted typical applications as proof-of-principles to verify the methodology's general usefulness in detecting small organic molecules in distinct samples. Hence, various aldehydes (2-furaldehyde, valeraldehyde, and benzaldehyde) in spiked cachaça samples (an alcoholic drink produced from fermentation/distillation of sugarcane juice) were promptly detected using a reagent pencil doped with 4-aminophenol (the reactive compound). Similarly, we recognized typical ginsenosides and triacylglycerols (TAGs) in ginseng aqueous infusions and soybean oil samples, respectively, using lithium chloride as the reactive compound. The results indicate that the reagent-pencil methodology is compatible with PS-MS and provides an easy and fast way to detect target analytes in complex samples. The advantage over the usual solution-based deposition of reagents lies in the lack of preparation or carrying different specific solutions for special applications, which can simplify operation, especially in point-of-care analysis with fieldable mass spectrometers.

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MAIN CONCLUSION: Cotton genotypes displayed similar volatile organic compound (VOC) profiles, but major differences in terpenoid aldehyde (TA) content. The differences in VOC production were minor among genotypes, but these differences are crucial for boll weevil attraction. Weevils did not display any preference in feeding behaviour towards cotton genotypes, suggesting physiological adaptation to cope with cotton chemical defence mechanisms. Plant cultivar selection for resistance to herbivore pests is an effective, environmentally safe and inexpensive method to implement in integrated pest management programmes. In this study, we evaluated seven cotton genotypes with respect to the production of volatile organic compounds (VOCs) and non-volatile compounds [terpenoid aldehydes (TAs)], and the attraction and feeding preference of adult boll weevils. Chemical analyses of VOCs from BRS-293, BRS-Rubi, CNPA TB-15, CNPA TB-85, CNPA TB-90, Delta Opal, and Empire Glandless showed that there were few qualitative and quantitative differences across the range of genotypes. In contrast, major differences in TA content were observed, with CNPA TB-15 and CNPA TB-85 producing higher levels of TAs compared to the other genotypes. Our results showed that boll weevil attraction to cotton genotypes varied, suggesting that the ratios and quantities of emitted cotton VOCs are important for host location. However, boll weevil feeding behaviour was neither positively nor negatively influenced by the terpenoid content (non-volatile compounds) of cotton genotypes. The results in this study suggest that boll weevils have adapted physiologically to cope with cotton chemical defence mechanisms.

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Cytochrome c (cytc) is a heme protein of 12 kDa that transfers electrons in the mitochondrial respiratory chain. Increased cytc peroxidase activity leads to cardiolipin (CL) oxidation, a hallmark of early apoptosis stage. Here, we aimed to investigate the interaction between cytc with cardiolipin hydroperoxide (CLOOH) in a mimetic mitochondrial membrane. Cytc-CL peroxidase reaction occurred at faster rates with CLOOH than with H2O2. Moreover, liposomes containing CLOOH promoted increased protein aggregation with minor or no release of cytc from the membrane. Dimeric and trimeric cytc species were observed in the first 15 min, followed by increased formation of high-molecular-weight aggregates afterwards. nLC-MS/MS analysis identified several Lys and His residues covalently modified by lipid aldehydes that showed mass increments corresponding to 4-hydroxynonenal (HNE), 4-oxononenal (ONE), hexanoyl, heptenal and octenal addition. Noteworthy, most modifications were observed at Lys and His residues located at A-site (K73, K87, K88), L-site (H26, H33, and K27) membrane binding sites. Further, dityrosine cross-linked peptides were also characterized at residues Y48-Y74, Y48-Y97 and Y74-Y97. Collectively, our findings show that CLOOH causes irreversible protein damage and crosslinking of cytc in the membrane.

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Metal-deficient Cu,Zn-superoxide dismutase (apo-SOD1) is associated with the formation of SOD1 aggregates that accumulate in ALS disease. The data supplied in this article support the accompanying publication showing SOD1 modification and aggregation induced by lipid aldehydes [1]. Here, we present the LC-MS/MS dataset on apo-SOD1 modification induced by seven different lipid aldehydes: 4-hydroxy-2-hexenal (HHE), 4-hydroxy-2-nonenal (HNE), 2-hexen-1-al (HEX), 2,4-nonadienal (NON), 2,4-decadienal (DEC) or secosterol aldehydes (SECO-A or SECO-B). Modified protein samples were digested with trypsin and sequenced by a LC coupled to a Q-TOF instrument. Protein sequencing and peptide modification analysis was performed by Mascot 2.6 (Matrix Science) and further validated by manual inspection. Mass spectrometry data (RAW files) obtained in this study have been deposited to MassIVE and the observed peptide-aldehyde adducts can be used in further studies exploring SOD1 modifications in vivo.

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Unsaturated lipids are oxidized by reactive oxygen species and enzymes, leading to the increased formation of lipid hydroperoxides and several electrophilic products. Lipid-derived electrophiles can modify macromolecules, such as proteins, resulting in the loss of function and/or aggregation. The accumulation of Cu,Zn-superoxide dismutase (SOD1) aggregates has been associated with familial cases of amyotrophic lateral sclerosis (ALS). The protein aggregation mechanisms in motor neurons remain unclear, although recent studies have shown that lipids and oxidized lipid derivatives may play roles in this process. Here, we aimed to compare the effects of different lipid aldehydes on the induction of SOD1 modifications and aggregation, in vitro. Human recombinant apo-SOD1 was incubated with 4-hydroxy-2-hexenal (HHE), 4-hydroxy-2-nonenal (HNE), 2-hexen-1-al (HEX), 2,4-nonadienal (NON), 2,4-decadienal (DEC), or secosterol aldehydes (SECO-A or SECO-B). High-molecular-weight apo-SOD1 aggregates dramatically increased in the presence of highly hydrophobic aldehydes (LogPcalc > 3). Notably, several Lys residues were modified by exposure to all aldehydes. The observed modifications were primarily observed on Lys residues located near the dimer interface (K3 and K9) and at the electrostatic loop (K122, K128, and K136). Moreover, HHE and HNE induced extensive apo-SOD1 modifications, by forming Schiff bases or Michael adducts with Lys, His, and Cys residues. However, these aldehydes were unable to induce large protein aggregates. Overall, our data shed light on the importance of lipid aldehyde hydrophobicity on the induction of apo-SOD1 aggregation and identified preferential sites of lipid aldehyde-induced modifications.

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Citrus limon (L.) Burm is an important crop that grows between latitudes 30° North and 30° South, the main producers being China, the USA, Mexico, India, Brazil, and Spain. In Spain, lemon grows mainly in Mediterranean areas such as Murcia, Valencia, and Andalucía. The most cultivated varieties are "Fino" and "Verna". In this study, five varieties of lemon, "Verna", "Bétera", "Eureka", "Fino 49", and "Fino 95" were evaluated on different rootstocks: three new Forner-Alcaide ("FA13", "FA5", "FA517"), Citrus macrophylla, Wester, and Citrus aurantium L. Hydrodistillation was used to obtain essential oil from fresh peels and then the volatile profile was studied by gas chromatography-mass spectrometry (GC-MS). A total of 26 volatile compounds were identified, limonene being the main one followed by ß-pinene, γ-terpinene, sabinene, and α-pinene. The results revealed that Forner-Alcaide rootstocks ("FA5" > "FA517" > "FA13") proved to be the best rootstocks for the aroma quality as they led to high volatile contents, followed by C. aurantium and C. macrophylla. Among the other varieties, the most aromatic one was "Eureka". The whole trend was as follows (in decreasing order): "Eureka" > "Bétera" > "Fino 95" > "Verna" > "Fino 49".

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Aldo-keto reductases (AKRs) are nicotinamide-dependent enzymes that catalyze the transformation of aldehydes and ketones into alcohols. They are spread across all phyla, and those from microbial origin have proved to be highly robust and versatile biocatalysts. In this work, we have discovered and characterized a microbial AKR from the yeast Rhodotorula mucilaginosa by combining genome-mining and expression assays. The new enzyme, named AKR3B4, was expressed by a simple protocol in very good amounts. It displays a selective substrate profile exclusively transforming aldehydes into alcohols. Also, AKR3B4 shows very good stability at medium temperatures, in a broad range of pH values and in the presence of green organic solvents. Conversion assays demonstrate it is an excellent biocatalyst to be used in the synthesis of aromatic alcohols, and also to produce furan-3-ylmethanol and the valuable sweetener xylitol. These results show that AKR3B4 displays attractive features so as to be used in chemoenzymatic processes.

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The 4-Hydroxycoumarin derivatives are known to show a broad spectrum of pharmacological applications. In this paper we are reporting the synthesis of a new series of 4-Hydroxycoumarin derivatives synthesized through Knovenegal condensation; they were characterized by using UV-Vis, FT-IR, NMR spectroscopies. The synthesized compounds were evaluated for antibacterial activity against Staphylococcus aureus and Salmonella typhimurium strains. The compounds (2), (3) and (8) showed favorable antibacterial activity with zone of inhibitions 26.5± 0.84, 26.0 ± 0.56 and 26.0 ± 0.26 against Staphylococcus aureus (Gram-positive) respectively. However, the compounds (5) and (9) were found more active with 19.5 ± 0.59 and 19.5 ± 0.32 zone of inhibitions against Salmonella typhimurium (Gram-negative). Whereas, in urease inhibition assay, none of the synthesized derivatives showed significant anti-urease activity; although, in carbonic anhydrase-II inhibition assay, the compound (2) and (6) showed enzyme inhibition activity with IC50 values 263±0.3 and 456±0.1, respectively.

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Cell physiology parameters are essential aspects of biological processes; however, they are difficult to determine on-line. Dielectric spectroscopy allows the on-line estimation of viable cells and can provide important information about cell physiology during culture. In this study, we investigated the dielectric property variations in Kluyveromyces marxianus SLP1 and Saccharomyces cerevisiae ERD yeasts stressed by 5-hydroxymethyl-2-furaldehyde and 2-furaldehyde during aerobic growth. The dielectric properties of cell permittivity, specific membrane capacitance (Cm), and intracellular conductivity (σIn) were considerably affected by furan aldehydes in the same way that the cell population, viability, cell size, substrate consumption, organic acid production, and respiratory parameters were. The yeasts stressed with furan aldehydes exhibited three physiological states (φ): adaptation, replicating, and nonreplicating states. During the adaptation state, there were small and stable signs of permittivity, Cm, and σIn; additionally, no cell growth was observed. During the replicating state, cell growth was restored, and the cell viability increased; in addition, the permittivity and σIn increased rapidly and reached their maximum values, while the Cm decreased. In the nonreplicating state, the permittivity and σIn were stable, and Cm decreased to its minimum value. Our results demonstrated that knowing dielectric properties allowed us to obtain information about the physiological state of the cells under control and stressed conditions. Since the permittivity, Cm, and σIn are directly associated with the physiological state of the yeast, these results should contribute to a better understanding of the stress response of yeasts and open the possibility to on-line monitor and control the physiological state of the cell in the near future.

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Aldehydes are important compounds in a large number of samples, especially food and beverages. In this work, for the first time, cyclohexane-1,3-dione (CHD) was used as a derivatizing reagent aiming aldehyde (formaldehyde, acetaldehyde, propionaldehyde, and valeraldehyde) analysis by MEKC-DAD. The optimized separation of the derivates was performed using a voltage program (+20 kV, 0-15 min.; +23 kV, 15-17 min.) at a temperature of 26°C, and using as the running buffer a mixture containing 100 mmol/L of sodium dodecyl sulfate and 29 mmol/L of sodium tetraborate at pH 9.2, with maximum absorbance at 260 nm. CHD was compared with two other derivatizing agents: 3-methyl-2-benzothiazolinone hydrazone and phenylhydrazine-4-sulfonic acid. The CHD-aldehyde derivatives were also characterized by LC-MS. The calibration curves for all aldehydes had r2 above 0.999 and LODs ranged from 0.01 to 0.7 mg/L. The optimized methodology was applied in sugar cane brandy (cachaça) samples successfully. CHD showed to be an alternative derivatization reagent due to its stability, aqueous solubility, high selectivity and sensitivity, reduced impurities, and simple preparation steps.

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The Brazilian legislation does not establish limits or methodology for the measurement of aldehydes in the exhaust of heavy diesel engines. No conclusive studies on aldehyde emissions by such engines have been found in the literature available. This work measured the aldehyde emissions from a P7 diesel cycle engine (EURO V), which was tested on an engine test bench according to ETC (European Transient Cycle) and ESC (European Stationary Cycle) cycles using fuels with 5, 7 and 20% v/v of biodiesel and 10 and 500 ppm of sulphur. The results showed that biodiesel participation in the mixture did not significantly affect the aldehyde emissions of the tested engine and that the emission level generated in the ETC cycle is higher than that obtained with the ESC cycle. The diesel content in the blend was weakly and negatively correlated with the pollutant emissions, and the inverse pattern was observed for biodiesel. This finding indicates that an increase in biodiesel content causes a slight increase in pollutant emissions. Regarding the sulphur content, positive correlations between the sulphur content and particulate matter, NOx, CO and total hydrocarbon emissions were observed. When comparing the test cycles, the results were significantly different, with higher values for the ETC cycle.

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