Degree Of Unsaturation Research Articles

Effect of vegetable oil unsaturation and minor polar components on the physical properties of rice bran wax oleogels.

For the practical application of oleogels and to produce oleogels with consistent properties, a full understanding of the factors affecting properties of oleogels is necessary. This study aimed to understand the effects of type of oil and minor components in oils on the properties of 3% and 7% rice bran wax (RBW) oleogels, which were prepared with 12 vegetable oils with different degrees of unsaturation as well as the same oils where polar compounds were removed (stripped oils). Correlation coefficients of iodine values (IVs) of oils with the firmness of 3% and 7% RBW stripped oil oleogels were -0.632 and -0.499, respectively, indicating that the gel strength decreased with increasing unsaturation of oil. The gel strength increased after removing polar compounds in oil for all the oleogel samples. Higher unsaturation of oil resulted in higher solid wax contents (SWCs) in 7% RBW stripped oil oleogels (r=0.617), which, however, did not affect the gel strength. Very thin, large platelet wax crystals were observed under phase-contrast microscopy, which were almost identical across the oleogel samples. The permeation of dyed oil through oleogels was faster with unstripped oil oleogels than stripped oil oleogels, and the negative correlation between the color permeation rate and the firmness of oleogels was significant (r=-0.602 at Day 28) indicating that defects in the three-dimensional crystal network is an important factor for the gel strength. This study found several important factors affecting the physical properties of RBW oleogels, which can be applied to their practical applications. PRACTICAL APPLICATION: For the practical application of oleogels, factors affecting properties of oleogels must be fully understood so that the quality of oleogel-containing food products could be well controlled. Although oil is the major component of oleogels, the effect of the type of oil on oleogel properties was not well understood to date, and this study revealed very important relationships between oil properties and oleogel properties, which can be applied to the production of oleogel-containing products. The major findings are that gel strength was higher with lower unsaturation of oil and less polar compounds in oil and that melting temperature was higher with higher unsaturation of oil.

A large, multi-site lipidomic investigation of parity and aging in dairy cows.

Efforts to optimize the longevity of dairy cows are hindered by the increased risk of adverse health events, culling or dying on farm with increased parity. Lipidomics provides a platform to help identify important biomarkers and biological pathways associated with increased parity and associated aging. A large, multi-site (15 pasture-based, 15 TMR farms) cross-sectional study collected plasma samples from nonlactating, late pregnant, 'dry' cow (696 cows, ~27 d prepartum) and peak-milk cows (796 cows, ~58 DIM) in a disproportionate stratified (parity: 0, 1, 2, > 2 for dry cows; 1, 2, 3, > 3 for peak-milk cows) random sampling frame. A total of 185 lipid species, comprising the lipids classes of phospholipids, sphingomyelins (SM) and triacylglycerols, were quantified in a targeted, liquid chromatography-mass spectrometry (LC-MS) approach. Dry and peak-milk cohorts were analyzed separately throughout. Variation in lipid profiles was mostly attributed to farm of origin (36-41% of variation), with feeding system explaining 13-21% and parity 6-9%, according to ANOVA simultaneous component analysis (ASCA) modeling. Multiple linear regression (MLR) and orthogonal-partial least squares (O-PLS) investigated the association of the lipid profile with age (d), while discriminate analysis compared 1st parity with > 3 parity cows in O-PLS discriminate analysis (O-PLS-DA), random forest (RF) and support vector machine (SVM) models. Rankings of the most important lipid species for each model type were compared. Phospholipids with 40 carbon atoms and 6 double bond equivalents (40:6) were consistently decreased with increasing parity and age across both dry and peak-milk cohorts. These lipids most likely contained stearate (18:0) and docosahexaenoic acid (DHA, C22:6;n-3), an omega-3 fatty acid. Additionally, phospholipids with 40:5, 38:6, lysophosphatidylcholine (17:0), SM(35:1), and SM(35:2) were commonly identified lipids that decreased in concentration with parity and age. Docosahexaenoic acid has been associated with improved cattle health, reproduction, and milk production and quality. This study raises the hypothesis that reduced DHA levels in older cows may be a significant factor increasing susceptibility to adverse health events, reduced reproductive performance, and herd removal. Studies that supplement DHA or its precursors can test this hypothesis and may be important in optimizing longevity of cows.

Experimental and theoretical studies on antioxidant and antibacterial properties of chitosan-gelatin functional composite films loaded with flavonoids

Chitosan-gelatin-flavonoid functional composite films were prepared with chitosan, gelatin, and three flavonoids (Naringenin, Apigenin, and Luteolin). The effect of three flavonoids on physical, antioxidant, and antibacterial properties of functional composite film was investigated from experimental and Density functional theory (DFT) simulations. The tensile strength, thermal stability, water solubility, water vapor permeability, antioxidant activity, and antibacterial activity of chitosan-gelatin-flavonoid functional composite films were improved with flavonoid (Naringenin, Apigenin, and Luteolin) incorporation. The release behavior of Apigenin from functional composite film was much lower than that of Naringenin or Luteolin. ABTS+ radical scavenging ability values of functional composite films followed: Luteolin (69.53 %) > Naringenin (41.39 %) > Apigenin (36.13 %). The antibacterial activities of functional composite films against Staphylococcus aureus followed: Luteolin (52.03 mm) > Apigenin (49.34 mm) > Naringenin (43.15 mm). The total number, location of hydroxyl groups on ring-B, and the unsaturation degree on pyrone ring of flavonoids influenced antioxidant and antibacterial activities of functional composite films. The minimum bond dissociation enthalpy values of flavonoids followed: Luteolin < Apigenin < Naringenin. The interaction energy of Apigenin-chitobiose was stronger than that of Naringenin or Luteolin. These results will shed light on flavonoid selection for functional composite films of food packaging.

MP-based plant oleogels structuring with various unsaturated oil: Fabrication, characterization, and in-vitro digestion.

Recently, research on the plant-based oleogels, has gained significant attention as a promising approach for oil formulation. In this research, emulsion-templated technique utilizing millet prolamin (MP) as oleogelator was employed for crafting edible oleogels from various vegetable oils of varying degree of unsaturation. The focus of the study was to examine the formation process, structural characteristics, rheological properties, and lipid digestion of these oleogels. The results indicated that MP-based oleogels exhibited uniform morphology and low oil loss. The construction of the oleogel network could be attributed to hydrogen bonding between oleogelator molecules, hydrophobic interactions among the oleogelator molecules and between the oleogelator and oil, as well as van der Waals forces between the oil molecules themselves. Increasing MP concentration formed a denser oleogel network, and exhibited greater elastic moduli (G') and viscous moduli (G''). Additionally, 8% MP oleogel prepared from flaxseed oil with high linolenic acid showed low oil loss, high hardness and efficient release of free fatty acids. These results indicated the potential of MP as an oleogelator in creating oleogels, and it is promising for fabricating trans-free and low-saturated oleogel-based products.

In silico analysis of the action of saturated, monounsaturated, and polyunsaturated fatty acids against Echinococcus granulosus fatty-acid-binding protein 1

Background The zoonotic infection caused by tapeworms Echinococcus is a neglected tropical disease in poor regions with limited access to suitable sanitary conditions. Hydatid cysts produced by Echinococcus granulosus use fatty-acid-binding proteins (FABP) to obtain the fatty acids and cholesterol necessary for their survival from the host. In this work, we analyzed the behaviour of saturated, monounsaturated, and polyunsaturated fatty acids against EgFABP1. Methods We used computational biology and chemistry techniques and binding free energy estimations by molecular mechanics generalized Born surface area (MM/GBSA). Results This research has enabled us to clarify the EgFABP1 isoforms identified in the database, suggesting their potential involvement in diverse cellular activities of Echinococcus granulosus. Conversely, examining the global and local chemical reactivity of 14 fatty acids revealed that liposolubility is contingent upon the degree of unsaturation in the FAs. Additionally, FAs exhibited acceptable levels of oral absorption and bioavailability. The binding of EgFABP1 with FAs analyzed by molecular dynamics simulation showed us that these are highly stable, where the best affinity was with docosahexaenoic acid. Conclusions Our results suggest that the action of fatty acids could play an interesting role in detecting early Echinococcus granulosus.

Response mechanism of Saccharomyces cerevisiae under benzoic acid stress in ethanol fermentation

Sugarcane molasses is an ideal economical raw material for ethanol production because of its wide availability, low cost and nutrient content. However, benzoic acid compounds with toxic effects on yeast cells are commonly found in sugarcane molasses. At present, the molecular mechanism of the toxic effects of benzoic acid on Saccharomyces cerevisiae has not been elucidated. Here, the toxic effect of exogenous benzoic acid on S. cerevisiae GJ2008 cells was studied, and the genes differentially expressed in S. cerevisiae GJ2008 after 1.2 g/L benzoic acid stress were identified via Illumina RNA-Seq technology. The results indicated that benzoic acid significantly inhibited yeast cell growth, prolonged their rapid growth period, and ultimately reduced their biomass. During ethanol fermentation using 250 g/L sucrose under 1.2 g/L benzoic acid stress, several adverse effects were observed, such as high residual sugar content, low ethanol concentration and low fermentation efficiency. In addition, the cell morphology was damaged, the cell membrane permeability increased, intracellular nucleic acid and protein leakage increased, and the malondialdehyde content significantly increased. Moreover, the cells protected themselves by significantly increasing the intracellular glycerol content. Fourier transform infrared spectroscopy proved that benzoic acid could reduce the degree of unsaturation and increase cell membrane permeability by changing the yeast cell wall and cell membrane composition, leading to cell damage and even death. Transcriptomic analysis revealed that under benzoic acid stress, the expression of genes associated with sucrose and starch metabolism, thiamine metabolism, the glycolysis pathway, fructose and mannose metabolism, galactose metabolism and ABC transporters was significantly downregulated. The expression of genes related to ribosomes, lipid metabolism, ribosome biosynthesis, nucleic acid metabolism, arginine and proline metabolism, RNA polymerase, metabolism related to cofactor synthesis, and biosynthesis of valine, leucine, and isoleucine was significantly upregulated. These results indicated that benzoic acid inhibited glycolysis and reduced sugar absorption and utilization and ATP energy supply in yeast cells. In response to stress, genes related to the ribosome bioanabolic pathway were upregulated to promote protein synthesis. On the other hand, the expression of ELO1, SUR4, FEN1 and ERG1 was upregulated, which led to extension of long-chain fatty acids and accumulation of ergosterol to maintain cell membrane structure. In conclusion, this paper provides important insights into the mechanism underlying the toxicity of benzoic acid to yeast cells and for realizing high-concentration ethanol production by sugarcane molasses fermentation.

Influence of the Degree of Unsaturation in Fish Oil Supplements on Oxidative Stress and Protein Carbonylation in the Cerebral Cortex and Cerebellum of Healthy Rats.

ω-3 polyunsaturated fatty acids (PUFAs) are crucial for brain structure and function, especially docosahexaenoic acid (DHA). However, an excess of DHA may increase lipid peroxidation due to its high degree of unsaturation, particularly in tissues highly susceptible to oxidative stress, such as the brain. Therefore, this study evaluated the effects of 10 weeks of dietary supplementation with fish oil containing 80% DHA on oxidative stress and the modulation of the carbonylated proteome in both the cerebral cortex and cerebellum of male Sprague Dawley rats. The results were compared with those induced by oils with a lower degree of fat unsaturation (fish oil containing 25% DHA and 25% eicosapentaenoic acid, soybean oil containing 50% linoleic acid and coconut oil containing 90% saturated fat). The results demonstrated that fish oil containing 80% DHA significantly increased the ω3/ω6 ratio in both the cortex and cerebellum while stimulating antioxidant defense by enhancing the reduced glutathione amount and decreasing the carbonylation of specific proteins, mainly those involved in glycolysis and neurotransmission. The majority of sensitive proteins in both brain regions followed this carbonylation trend (in decreasing order): soybean > EPA/DHA 1:1 > coconut > 80% DHA. The results also indicated that the cerebellum is more responsive than the cortex to changes in the cellular redox environment induced by varying degrees of fat unsaturation. In conclusion, under healthy conditions, dietary supplementation with fish oils containing high DHA levels makes the brain more resilient to potential oxidative insults compared to oils with lower DHA content and a lower degree of fatty acid unsaturation.

Chemical Landscape of Adipocytes Derived from 3T3-L1 Cells Investigated by Fourier Transform Infrared and Raman Spectroscopies.

Adipocytes derived from 3T3-L1 cells are a gold standard for analyses of adipogenesis processes and the metabolism of fat cells. A widely used histological and immunohistochemical staining and mass spectrometry lipidomics are mainly aimed for examining lipid droplets (LDs). Visualizing other cellular compartments contributing to the cellular machinery requires additional cell culturing for multiple labeling. Here, we present the localization of the intracellular structure of the 3T3-L1-derived adipocytes utilizing vibrational spectromicroscopy, which simultaneously illustrates the cellular compartments and provides chemical composition without extensive sample preparation and in the naïve state. Both vibrational spectra (FTIR-Fourier transform infrared and RS-Raman scattering spectroscopy) extended the gathered chemical information. We proved that both IR and RS spectra provide distinct chemical information about lipid content and their structure. Despite the expected presence of triacylglycerols and cholesteryl esters in lipid droplets, we also estimated the length and unsaturation degree of the fatty acid acyl chains that were congruent with known MS lipidomics of these cells. In addition, the clustering of spectral images revealed that the direct surroundings around LDs attributed to lipid-associated proteins and a high abundance of mitochondria. Finally, by using quantified markers of biomolecules, we showed that the fixative agents, paraformaldehyde and glutaraldehyde, affected the cellular compartment differently. We concluded that PFA preserves LDs better, while GA fixation is better for cytochromes and unsaturated lipid analysis. The proposed analysis of the spectral images constitutes a complementary tool for investigations into the structural and molecular features of fat cells.

Intrinsic Chemical Drivers of Organic Aerosol Volatility: From Experimental Insights to Model Predictions

AbstractAccurately predicting the volatilities of molecules in aerosols is challenging but crucial for understanding the atmospheric effects of aerosols. We used negative and positive ion electrospray ionization Fourier‐transform ion cyclotron resonance mass spectrometry (FT‐ICR MS) to identify differences in the molecular compositions of gas and particle phase samples from urban atmosphere. We aimed to identify intrinsic chemical parameters that determine and predict the organic aerosol volatility. We found higher average molecular weights, carbon mass percentages, and double bond equivalents (DBE) but lower average O/C ratios and oxygen mass percentages in the particle phase than the gas phase. We identified DBE, which display a significant negative correlation with volatility, as a key parameter. We proposed to improve the previous model for predicting organic aerosol volatility by incorporating DBE as a new variant; and the result showed that this subsequently improved the accuracy of the model, particularly for compounds with minimal or no heteroatoms (0–2) such as hydrocarbons (CH). The revised model offers insights into the contributions of DBE, carbon, nitrogen, oxygen, and sulfur atoms to the volatilities of diverse organic molecules in aerosols and could be applied to improve our understanding of the phase distributions of volatile organic compounds in the ambient air.

Relationship between the molecular structure of soluble organic matter in a subbituminous coal and the electrochemical properties of prepared supercapacitor

Carbon-based supercapacitors (SCs) are potential energy storage apparatuses, and the molecular and structural characteristics of carbon sources determine the performance of electrode materials. Coal-based porous carbon proves to be a potential candidate for the electrode materials of SC because of its high chemical stability, conductivity, and specific surface area. In the present study, the soluble substances thermally extracted from a subbituminous coal were utilized as the carbon source for the preparation of porous carbon materials (HS-X-PCs). The molecular composition of the carbon source was analyzed by using gas chromatography/mass spectrometry (GC/MS) and orbitrap-MS. HS-Et-PC exhibited a honeycomb pore structure with micropores and mesopores, consisting of a 3D network, while the carbon materials showed an amorphous structure. The electrochemical performance of HS-X-PCs was investigated, and HS-Et-PC exhibited the best performance with a specific capacitance of 195 F/g at 0.1 A/g and a retention rate of 100% after 10,000 cycles. The molecular structure of the carbon sources was elucidated by the two MS systems, and the double bond equivalence plots indicated the unsaturation degree of components. The active sites for electronic storage provided by pyrrolic-N and pyridine-N lead to the formation of additional pseudocapacitance. ON-containing compounds can form π-π conjugation with substances possessing highly condensed aromatic cores, which is advantageous for electron transfer and enhances the electrochemical performance of electrode materials.

Biovalorization of whey waste as economic nutriment for mycogenic production of single cell oils with promising antibiofilm and anticancer potentiality

The production of value-added bio-compounds from rejuvenated sources and their recruitment for healthcare services are paramount objectives in the agenda of white biotechnology. Hereupon, the current study focused on economic production of single cell oils (SCOs) from oleaginous fungi Alternaria sp. (A-OS) and Drechslera sp. (D-OS) using cheese whey waste stream, followed by their evaluation as antibiofilm and anticancer agents, for the first time. As a sole substrate for growth, the whey aided in lipid accumulation by 3.22 and 4.33 g/L, which representing 45.3 and 48.2% lipid content in Drechslera sp. (D-OS) and Alternaria sp. (A-OS), respectively. Meanwhile, a higher unsaturation degree was detected in A-OS by 62.18% comparing to 53.15% of D-OS, with advantageous presence of omega-6 poly unsaturated fatty acid by 22.67% and 15.04% for A-OS and D-OD, respectively, as revealed by GC-MS and FTIR characterization analysis. Interestingly, an eminent and significant (P ≤ 0.05) antibiofilm potency was observed in a dose-dependent modality upon employing both SCOs as antibiofilm agents. Whereas, 100 µg/mL of A-OS recorded superior inhibition of P. aeruginosa, S. aureus and C. albicans biofilms development by 84.10 ± 0.445, 90.37 ± 0.065 and 94.96 ± 0.21%, respectively. Whereas, D-OS (100 µg/mL) thwarted the biofilms of P. aeruginosa, S. aureus and C. albicans by 47.41 ± 2.83, 62.63 ± 5.82 and 78.67 ± 0.23%, correspondingly. Besides, the metabolic performance of cells within biofilm matrix, protein, carbohydrate contents and hydrophobicity of examined biofilms were also curtailed in a significant correlation with biofilm biomass (r ≥ 0.9). Further, as anticancer agents, D-OS recorded higher potency against A549 and CaCo-2 cell lines with IC50 values of 2.55 and 3.425% and SI values of 10.1 and 7.5, respectively. However, A-OS recorded 8.275% and 2.88 for IC50 and SI of Caco-2 cells, respectively. Additionally, A-OS activated caspase 3 by 64.23 ± 1.18% and 53.77 ± 0.995% more than D-OS (52.09 ± 0.222% and 49.72 ± 0.952%) in A549 and Caco-2 cells, respectively. Furthermore, the enzymes, which associated with cancer invasion, metastasis, and angiogenesis (i.e., MMP2 and MMP9) were strongly inhibited by A-OS with 18.58% and 8.295%, respectively as IC50 values; while D-OS results recorded 23.61% and 13.16%, respectively, which could be ascribed to the higher ω-6/ω-3 contents of A-OS. The promising results of the current study opens up the vision to employ SCOs as anti-infective nutraceuticals and in complementary/alternative therapy and prophylactic programs as well.

Molecular Characterization and Photoreactivity of Organic Aerosols Formed from Pyrolysis of Urban Materials during Fires at the Wildland-Urban Interface.

Fires at the wildland-urban interface (WUI) are increasing in magnitude and frequency, emitting organic aerosol (OA) with unknown composition and atmospheric impacts. In this study, we investigated the chemical composition of OA produced through the 600 °C pyrolysis of ten urban materials in nitrogen, which were subsequently aged under UV light for 2 h. The analysis utilized ultrahigh-performance liquid chromatography (UHPLC) separation, coupled with a photodiode array (PDA) detector and a high-resolution mass spectrometer (HRMS) for molecular characterization. Hierarchical clustering analysis demonstrated that lumber-derived OA was the most diverse and distinct in composition. Unaged and aged OA (for each urban material) did not significantly differ in chemical identities. Potential aromatic brown carbon (BrC) chromophores (based on their degree of unsaturation) constituted 13-42% of all assigned compounds. PDA chromatograms revealed multiple BrC chromophoric species that were either enhanced or degraded as a result of UV aging, providing insights into specific BrC chromophores responsible for photobleaching and photoenhancement of the overall absorption coefficient. Thirty-six BrC chromophores were identified across the ten OA types, and their structures were confirmed using reference standards. Components of plasticizers and resins, such as phthalic and terephthalic acids, were structurally confirmed in the samples. We present potential species for WUI fires as components of resins, epoxies, dyes, and adhesives commonly used in manufacturing urban materials. Photolysis did not significantly impact the chemical composition of OA emitted from the burning of specific WUI materials.

Revealing the backbone structures of land-based fulvic acids derived from river and soil through n-butylsilane reduction.

While ultra-high-resolution mass spectrometry has enabled the identification of the molecular composition of dissolved organic matter (DOM), elucidating its molecular structure remains a challenging endeavor. Here, two fulvic acids (FAs), one from river and the other from forest soil, were subjected to reduction using an optimized n-butylsilane (n-BS) reduction method. The reduction products were purified through a combination of liquid-liquid extraction and silica gel column chromatography, resulting in the separation into saturates, aromatics, and polar products. The polar products were analyzed by high-resolution mass spectrometry (HRMS), and the saturates and aromatics were analyzed using gas chromatography-mass spectrometry (GC-MS). HRMS results showed that the number of oxygen atoms and double-bond equivalent (DBE) values of FA decreased after reduction. GC-MS results revealed that a total of 270 hydrocarbon monomers were identified from the reduction products of a single sample, with the highest carbon number of cycloalkanes reaching C33. For the first time, steranes and hopanes were detected in the reduction products, potentially serving as evidence for the existence of carboxyl-rich alicyclic molecule (CRAM) precursors. Additionally, a significant number of polycyclic aromatic hydrocarbons were identified, and the potential sources of various compounds were preliminarily inferred based on their isomers. This study extends the knowledge of the possible backbone structure of the DOM and provides a new potential tool for investigating the origin and transformation mechanisms of DOM.

Replacing soybean meal with house cricket (Acheta domesticus) meal in ruminant diet: effects on ruminal fermentation, degradation, and biohydrogenation

Abstract Insect meals could be a sustainable protein source in ruminant diets to overcome the environmental, market, and feed-food-fuel issues associated with the widespread use of soybean meal (SBM). However, research on this topic is still very scarce. This study was conducted to examine the possibility of replacing SBM with house cricket (Acheta domesticus) meal (HCM) in ruminant feeding. Four cannulated sheep were fed a total mixed ration containing either 10% SBM (Control diet) or 10% of non-defatted HCM (Insect diet) over two consecutive periods. Effects on ruminal fermentation, degradation, and biohydrogenation were evaluated. Despite some differences in rumen dry matter and N degradation kinetics, replacing dietary SBM with HCM did not affect the ruminal disappearance of dry matter, N and, neutral detergent fibre of in situ incubated feedstuffs. Nor were there differences between the meals in the in vitro intestinal digestibility of rumen non-degraded nitrogen. The replacement had no negative effects on rumen pH or ammonia concentrations, but resulted in lower total and individual (i.e. acetate, propionate, butyrate, and minor) volatile fatty acid concentrations. This adverse effect was probably due, at least in part, to the unexpectedly high content of fat in HCM and its relatively high degree of unsaturation. Inclusion of HCM in the diet facilitated modulation of the fatty acid profile of the rumen digesta without negative effects on biohydrogenation pathways (e.g. it increased trans-11 18:1 and cis-9 trans-11 CLA concentrations, with only a small variation in the trans-10:trans-11 18:1 ratio). Replacing SBM with HCM in ruminant diets could be a promising alternative to address the challenges related to SBM and to improve the lipid composition of ruminant-derived products. However, further research is still needed to investigate, for example, the most appropriate level of inclusion of HCM in the diet or the use of defatted meal.

Molecular characterization of atmospheric organic aerosols in typical megacities in China

Atmospheric aerosols in megacities impact air quality and public health. However, limited information exists on the detailed molecular composition of organic aerosols in urban areas. This study characterized the molecular composition of organic aerosols (OA) in Shanghai, Beijing and Guangzhou, China, during summer and winter of 2021. Liquid chromatography-orbitrap mass spectrometry detected 4536−5560 and 2067− 3489 organic molecular formulas in positive (ESI+) and negative (ESI−) electrospray ionization modes, respectively. CHO and CHON compounds accounted for over 80% and 60% of total abundance in ESI+ and ESI−, respectively, suggesting their significant contribution to urban OA. The number and abundance percentages of CHO showed obvious seasonal variation, with more CHO in summer than in winter, while CHON exhibited the opposite trend in Beijing and Shanghai. Compared with winter, a lower unsaturation degree, reduced aromaticity, and higher oxidation state of OA in summer were observed in Beijing and Shanghai, while these seasonal variations were not as obvious in Guangzhou, likely due to regional climate differences. The number percentage of common compounds between Beijing and Shanghai was higher than that between Guangzhou and Beijing (or Shanghai). Nitroaromatic compounds were more prevalent in winter than in summer. Further analysis of atmospheric formation relevance and precursor-product pairs suggested that CHON compounds are derived from the oxidization or hydrolyzation processes, revealing potential chemical transformations of these aerosols. This study characterized the chemical makeup of organic aerosols, providing insight into their sources and characteristics in these cities.

Comparison of environmental impacts from pyrolysis, gasification, and combustion of oily sludge

Thermochemical treatment of oily sludge (OS) has been demonstrated to be an effective approach for resource and energy recovery. However, the migration and emission of potential pollutants have limited its further development. In this study, the environmental impacts, including aromatic compounds in liquid products, N-, S-, and Cl-containing pollutants in gaseous products, and residual organic matter and heavy metals in solid residues, during the pyrolysis, gasification, and combustion processes of OS are comparatively investigated. The results indicate that the aromatics in the liquid products obtained from pyrolysis and gasification are primarily hydrocarbons with 10, 14, and 16 carbon atoms, and the corresponding degree of unsaturation is between 7 and 16. By contrast, the aromatics produced during combustion are mainly hydrocarbons with 10–12 carbon atoms and an unsaturation degree of 7. The liquid products from gasification of OS contain aromatics with more carbon atoms and a higher degree of unsaturation, suggesting potential issues of recalcitrant aromatics and tar by-products during the gasification process. The release behaviors of N-, S-, and Cl-containing pollutants during the thermochemical treatment of OS are closely related to the specific thermochemical technology and treatment temperature. At 550 °C, these pollutants are gradually released from the OS. By contrast, at 950 °C, they are released over a narrow temperature range with significantly higher concentrations. Furthermore, compared with the peak concentrations of SO2 and HCl during thermochemical processing at 550 °C, these values increase by 1–2 orders of magnitude at 950 °C. With the increase in treatment temperature, the loss on ignition (LOI) of residues from pyrolysis or gasification of OS gradually decreases and stabilizes around 0.5 %. On the other hand, the LOI from combustion fluctuates around 1.0 %. In addition, the removal rates of total organic carbon in the residues from all three thermochemical processes exceed 98.89 %. However, the potential ecological risks associated with heavy metals in the residues from thermochemical treatment of OS also increase to some extent. Cr, Cu, and Zn are found to evaporate and escape into liquid and gaseous products, while Pb is retained in the residues. Notably, the residue from combustion poses the highest environmental risks among the three processes.

Assessment of the Migration of Polar Compounds from Petroleum-Contaminated Soil Using a Column Leaching Experiment.

When petroleum leaks into soil, the polar compounds exhibit strong biological toxicity, causing serious damage to soil animals, plants, and microorganisms and potentially threatening human health. However, the systematic comprehension of the migration of polar compounds in petroleum-contaminated soil remains limited. Herein, we employed elemental analysis, stable carbon isotope analysis, and high-resolution mass spectrometry techniques to study the migration of polar compounds in petroleum-contaminated soil using a column leaching experiment. The results indicate that petroleum migration ability in soil is limited, and the compounds are primarily concentrated in the soil above 40 cm. The C/N, C/H, and δ13C ratios of organic matter in soils are highly affected by petroleum contamination. Meanwhile, the different compound classes show varying migration abilities, with N1 and N1O1 compounds exhibiting stronger adsorption capacity on soil, while oxygen-containing compounds are more likely to migrate with water to deeper soil. Additionally, molecular polarity, unsaturation degree, and size are key factors affecting the migration of polar compounds in petroleum within the soil. This simulation experiment offers valuable insights into comprehending migration of polar compounds in petroleum-contaminated soil and their potential impacts for soil ecological environment.

Microencapsulation and characterization of pomegranate seed oil using gum Arabic and maltodextrin blends for functional food applications.

Pomegranate seed oil (PSO) is highly valued in the functional food industry due to its rich fatty acid content and associated health benefits. However, its high degree of unsaturation makes it susceptible to rapid degradation when exposed to oxygen and light. This study investigates the encapsulation of PSO at 15% w/w using different blends of gum Arabic (GA) and maltodextrin (MD) (1:0, 0:1, 1:1, 3:1, and 1:3) to determine optimal formulations for enhanced stability and functional quality. Characterization of the encapsulated PSO powders showed distinct particle morphologies, including flake-like shapes and textures ranging from smooth to wrinkled and porous. The Fourier transform infrared (FT-IR) spectra indicated shifts in functional groups from 2973.70 to 408.84 cm-1, revealing the presence of aliphatic, amine, aromatic, carboxylic acid, and hydroxyl groups. Although no single formulation achieved all desired outcomes, the GA:MD ratios of 1:0 and 1:1 were superior in enhancing color properties (yellowness and chroma), techno-functional attributes (bulk density and solubility), and in preserving essential fatty acids, including stearic, cis-oleic, α-linolenic, arachidic, γ-linolenic, linoleic, and punicic acids. Additionally, GA:MD (3:1) powders exhibited superior ferric-reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities (RSA). In conclusion, formulations using solely GA or GA:MD ratios of 1:1 and 3:1 effectively preserve bioactive content in PSO, enhancing its antioxidant capacity. These findings suggest promising applications for these encapsulated powders in developing functional foods that meet industry demands.

Elucidating maternal provisioning for bivalve larvae under ocean acidity extreme events

Ocean acidity extreme (OAX) events, triggered by climate change and anthropogenic activities, are projected to become more intense and frequent in coastal ecosystems, devastating marine bivalves and ecosystems they support. Maternal effects adaptively modulate offspring performance in response to climatic stressors, but whether and to what extent they can confer offspring resistance to OAX remain largely unknown. Here, we investigated impacts of OAX on the parental and larval lipidomes of Manila clams (Ruditapes philippinarum) to add further insights into the energetic nature of maternal effects. A total of 177 significantly down-regulated lipid components (categorized into glycerolipids mainly) were shown in OAX-stressed adults compared with those reared under ambient conditions, and following parental conditioning, larvae also exhibited a further decreasing down-regulation of the glycerolipid components. Triacylglycerols were identified as the predominant composition of glycerolipids and the primary sources of energy for gonadal maturation and larvae development. Yet, larvae spawn from adults exposed to OAX had significantly lower contents of triacylglycerols than those without a prior history of parental conditioning, with the carbon chain length and unsaturation degree of the triacylglycerol components being significantly affected. The latter was also in line with significant increases in the production of triacylglycerol byproducts (diacylglycerols). Overall, our findings suggest that when OAX prevailed during reproductive seasons of Manila clams, maternal effects could be maladaptive by depressing the energetic deposition of larvae, and may not be a potential adaptive modulator of marine bivalves to cope with unprecedented environmental change.

Investigating the Influence of the Substrate Temperature and the Organic Precursor on the Mechanical Properties of Low‐Pressure Plasma Polymer Films

ABSTRACTThis work aims to investigate the influence of the substrate temperature on low‐pressure plasma polymerization processes. Emphasis is placed on the mechanical properties and growth mechanism of the plasma polymer films (PPFs). For this purpose, two precursors are considered, differing only by their unsaturation degree: 2‐propen‐1‐ol (CH2═CH–CH2–OH) and propan‐1‐ol (CH3–CH2–CH2–OH). Although propan‐1‐ol‐based PPFs behave like hard elastic solids, 2‐propen‐1‐ol‐based coatings evolve from a liquid film to an elastic solid on increasing the substrate temperature. This behavior is understood considering the evolution of the glass transition temperature of PPFs. The latter is correlated with the cross‐linking degree of the polymeric network governed by the energy density of bombarding ions on the growing film.