Search Results (255)

Our recent studies demonstrated that dialkylaminopyridine organocatalysts featuring an extensive secondary sphere preferentially phosphorylate the alcohol at the apolar domain of a model amphiphilic diol. In the present study, this site-selective behavior was corroborated across a broader range of amphiphilic diols. Furthermore, we found that the site selectivity can be inverted by applying certain saturated aliphatic amine bases in stoichiometric amounts. Screening identified cis-2,6-dimethylpiperidine as the most selective promoter, consistently inducing phosphorylation at the polar domain across all tested diols. Remarkably, despite being a secondary amine, this base did not produce any detectable phosphoramidate byproduct. Full article

Aging-associated dyslipidemia and chronic low-grade inflammation contribute to atherosclerosis and cardiovascular risk. As a blend of long-chain aliphatic alcohols, policosanol from insect wax (PIW) has been documented to regulate lipid metabolism. However, the effects of PIW on atherosclerosis remain insufficiently characterized. In this study, ApoE^−/− mice fed a high-fat diet were concurrently administered PIW (75 and 150 mg/kg) for eight weeks. PIW was associated with weight gain reduction and improvement in lipid profile, particularly a decrease in triglycerides and total cholesterol. PIW also lowered circulating inflammatory biomarkers (IL-6, TNF-α, and C-reactive protein). Histopathological analyses revealed attenuated hepatic injury and reduced aortic lipid deposition and lesion features. In parallel, PIW reduced serum endothelin-1 and oxidized LDL levels and modulated aortic ET-1, MMP-9/TIMP-1 balance, and LOX-1/NF-κB-related protein signals. Notably, as PIW was administered concurrently with high-fat diet induction, these findings should be interpreted within a preventive intervention framework. Collectively, PIW help attenuate HFD-associated atherosclerotic features and hold promise as a functional food ingredient for cardiovascular health and healthy aging. Full article

Fatty alcohols and aliphatic hydrocarbons occur abundantly in nature and serve as critical feedstocks for the surfactant and fuel industries, respectively. However, their industrial-scale separation and purification are significantly hampered by high boiling points and the formation of complex azeotropes. To address these challenges, this study explores a five-column high-vacuum pressure-swing distillation (HVPSD-5C) strategy. Vapor–liquid equilibrium (VLE) analysis of the key components (n-hexanol, n-octanol, n-dodecane, and n-tridecane) validated the thermodynamic viability of the process and established optimal operating conditions. To further enhance efficiency, a heat-pump-integrated configuration (HPI-HVPSD-5C) featuring vapor recompression and heat integration was designed, optimized, and evaluated. Comparison with the baseline HVPSD-5C process demonstrates that the HPI-HVPSD-5C configuration significantly improves sustainability and economics, reducing the total annual cost (TAC) by 17.48%, CO₂ emissions by 16.09%, and energy consumption cost by 12.79%. These findings provide a robust framework for the efficient separation of fatty alcohols from aliphatic hydrocarbons, offering a valuable reference for the purification of other pressure-sensitive azeotropic mixtures. Full article

This study aimed to characterize the impacts of high density polyethylene (HDPE) and polyethylene terephthalate (PET) on the co-pyrolysis mechanisms and products of municipal sludge (MS) by using thermogravimetric analysis. Compared with PET, the addition of 30% HDPE maximized the comprehensive pyrolysis index of MS from 7.68 to 20.37 × 10⁻⁶ %³/(min²·°C³). Between 350 and 500 °C, the facilitatory effect of the MS-PET co-pyrolysis was stronger than that of HDPE-MS. Between 500 and 1000 °C, the addition of PET/HDPE exerted an inhibitory effect on the MS pyrolysis. Prior to adding either plastic, the two main pyrolysis stages of MS followed distinct reaction models: a first-order reaction between 162.6 and 431.5 °C and a sixth-order (F6) reaction between 431.5 and 735.8 °C. However, the addition of HDPE transformed the high-temperature stage kinetics from the F6 model to nucleation growth. Throughout the (co-)pyrolysis process, the decomposition of alcohols, aliphatic hydrocarbons, acids, and aromatic substances occurred, accompanied by the formation of new aromatic compounds. The addition of HDPE further disrupted the char structure, while the addition of PET formed a barrier within the co-pyrolytic char, hindering the release of volatiles. Multi-objective optimization revealed that both HDPE and PET yielded superior energy performance compared with the MS pyrolysis. Increasing HDPE content further enhanced energetic optimization, with temperature and plastic type identified as the primary factors governing energy output at a heating rate of 10 °C/min. This study introduces a novel co-pyrolytic approach for tightening the co-circularity of both MS and PET/HDPE. Full article

Estimating the adsorption data and understanding the adsorption behavior and mechanism of organic pollutants on nanoplastics are crucial for assessing their ecological risks. Herein, in silico techniques, i.e., grand canonical Monte Carlo simulations, density functional theory computations, and quantitative structure activity relationship (QSAR) modeling, were integrated to examine the adsorption of 39 representative aliphatic and aromatic compounds and nine emerging pollutants (brominated flame retardants and phosphorus flame retardants) onto 12 different nanoplastics under atmospheric conditions. Three QSAR models were constructed to predict the adsorption equilibrium constant (logK) for polyethylene, polyoxymethylene, and polyvinyl alcohol nanoplastics individually, along with 12 QSAR models for separately estimating adsorption capacities (C_m) on different nanoplastics. Furthermore, a novel multi-dimensional prediction model was developed, enabling simultaneous, high-throughput prediction of adsorption capacities across multiple nanoplastics and pollutants with a single input. These results revealed that van der Waals and electrostatic interactions serve as the primary driving forces for the adsorption. The novel multi-dimensional prediction model facilitates rapid and comprehensive assessment of pollutant–nanoplastic interactions with one-click, and paves the way for improved risk evaluations and advancing predictive environmental research. Full article

The red imported fire ant, Solenopsis invicta Buren, is a eusocial insect that relies on a sophisticated chemical communication system for colony organization and function. Its olfactory system is vital for detecting semiochemicals in the environment. This study utilized single sensillum recording (SSR) to assess the olfactory neuronal responses of female alates and workers from basiconica sensilla exposed to a panel of 62 individual pheromones and general odorants, including terpenes, terpenoids, pyrazines, pyridines, ketones, aldehydes, alcohols, acids, aliphatic and aromatic acetates, benzoates, benzyl esters, and three essential oils. Basiconica sensilla, which contain multiple olfactory receptor neurons (ORNs), exhibited moderate to strong responses to most of the tested compounds, demonstrating a broad sensitivity to all odorants elevated. Comparative analysis of the two castes revealed that ORNs had similar responses to 47 odorants; however, workers showed stronger responses to nine specific compounds, while female alates responded more strongly to six others. These differences underscore the caste-specific olfactory tuning, likely reflecting their distinct roles within the colony. This study presents the first comprehensive mapping of basiconica sensilla responses to general odorants in S. invicta female alates and workers, enhancing our understanding of the S. invicta chemical ecology and potentially contribute to more effective fire ant management strategies. Full article

Capsaicin, a naturally occurring polyphenol, is known to affect energy expenditure and muscle fatigue and modulate contractions in skeletal muscle. The L-type Ca²⁺ channels are known to be an important ion channel involved in the various muscle functions and the effect of capsaicin on the skeletal L-type Ca²⁺ channels is currently unknown. In this study, the effects of capsaicin and capsaicin analogs on depolarization-induced Ca²⁺ effluxes through L-type Ca²⁺ channels in transverse tubule membranes from rabbit skeletal muscle and L-type Ca²⁺ currents recorded using the whole-cell patch clamp technique in rat myotubes were examined. Capsaicin, in the concentration range of 3–100 µM, inhibited depolarization-induced Ca²⁺ effluxes. The effect of capsaicin was not reversed by TRPV1 antagonist SB-366791 (10 µM). While vanilloids (30 µM) including vanillin, vanillyl alcohol, and vanillylamine were ineffective, other capsaicinoids (30 µM) including dihydrocapsaicin, nonivamide, and nordihydrocapsaicin significantly inhibited Ca²⁺ effluxes, suggesting that hydrocarbon chains are required for inhibition. In rat myotubes, capsaicin inhibited L-type Ca²⁺ currents with an IC₅₀ value of 27.2 μM in the presence of SB-366791. Furthermore, in docking studies and molecular dynamic simulations, capsaicinoids with an aliphatic tail showed stronger binding and stable bent conformations in CaV1.1, forming hydrogen bonds with Ser1011 and Thr935 and hydrophobic/π–alkyl contacts with Phe1008, Ile1052, Met1366, and Ala1369, resembling the binding mode of amlodipine. In conclusion, the results indicate that the function of L-type Ca²⁺ channels in mammalian skeletal muscle was inhibited by capsaicin and capsaicin analogs in a TRPV1-independent manner. Full article

Cuban sugarcane wax alcohol (policosanol) is a blend of eight characteristic aliphatic alcohols extracted from the Cuban sugarcane and widely recognized for its multifunctional applications and therapeutic properties. In the present study, the potency of policosanol (POL) was assessed for its ability to prevent metabolic stress and associated disorders posed by a high-cholesterol (HC) and high-galactose (HG) diet in zebrafish (Danio rerio). Adult zebrafish (n = 56/group) were fed either with an HC+HG diet (containing 4%, w/w cholesterol and 30%, w/w galactose), or an HC+HG amalgamated diet with POL (final 0.1% w/w or 0.5% w/w). Zebrafish in the specified groups were sacrificed post-30 weeks of feeding, and blood and organs (liver, brain, and eyes) were processed for biochemical, histological, and immunohistochemical (IHC) analysis. After 30 weeks of feeding, the highest mortality (12.5%) was noticed in the HC+HG supplement group, which was reduced to 4.5% with co-supplementation of POL (0.1% and 0.5%). In a dose-dependent manner, POL significantly reversed HC+HG elevated levels of total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), glucose, and malondialdehyde (MDA), while substantially augmenting plasma high-density lipoprotein cholesterol (HDL-C), sulfhydryl content, ferric ion reduction ability (FRA), and paraoxonase (PON) activity. In addition, POL mitigated HC+HG-induced hepatomegaly, inflammation, and fatty liver changes. Consistently, POL minimizes ROS generation and cellular senescence in the brain and substantially improves HC+HG-induced cognitive changes (cessation of swimming ability and motion), with a marked ~5 times higher swimming distance. Notably, POL mitigated the HC+HG-induced corneal opacity and attenuated oxidative stress, apoptosis, 4-hydroxynonenal (4-HNE) accumulation, and myelin sheath degeneration in the retina. The findings underscore the therapeutic potential of policosanol in attenuating oxidative stress, metabolic changes, and various organ damage caused by prolonged exposure to the HC+HG diet. Full article

The composition of the lipophilic components of Centaurea scabiosa L. has been studied. The raw material was subjected to extraction with hexane and methyl tert-butyl ether (MTBE) using both exhaustive and sequential schemes for a detailed characterization. The resulting extracts were fractionated into acidic and neutral components via treatment with alkali solutions. The acidic compounds were converted into methyl esters for subsequent gas chromatography–mass spectrometry (GC-MS) analysis, while the neutral unsaponifiable fractions were separated into groups of different polarities using column chromatography on silica gel. This approach enabled the identification of a complex profile of lipophilic substances. In the acidic fractions, aliphatic acids with chain lengths from C₁₀ to C₃₂, including unsaturated variants, were characterized. The neutral fractions revealed over compounds, encompassing n-alkanes, substantial levels of the unsaturated branched hydrocarbon squalene, and a diverse array of oxygenated terpenoids. The latter were mainly represented by highly active triterpene alcohols and ketones belonging to the ursane, oleanane, lupane, and cycloartane types. The sterol composition was dominated by β-sitosterol and accompanied by cholesterol, campesterol, stigmasterol, stigmast-7-en-3-β-ol, fucosterol, and stigmastan-3-β-ol. Bioactivity screening demonstrated that several of the obtained lipophilic extracts, particularly those of lower polarity, exhibited high inhibitory activity against the main protease of SARS-CoV-2, underscoring the potential of C. scabiosa as a valuable source of anti-coronavirus agents. Full article

To apply molecular dynamics (MD) simulations in the study of virgin asphalt binder, researchers have relied on basis sets of representative model structures from the SARA categories of saturated aliphatics (S), naphthenic aromatics (A), polar aromatics or resins (R), and asphaltenes (A). The evolution of these model compounds for MD of binder is reviewed with emphasis on addition of oxidized species for simulations of recycled aged binders. The level and type of oxygen functional groups in many MD simulations are not consistent with reported findings. Oxidation of primary, secondary, and tertiary benzylic carbons has been used as a rational approach to generate an extended basis set with functional groups reflecting ageing of virgin binder model compounds. Moieties known to be present in aged binder, though not wholly represented in prior work, include carboxylic acids, ketones, alcohols, anhydrides, and sulfoxides. A specific modified basis set for oxidized asphalt binder is proposed along with a methodology for generating other oxygen-consistent basis sets from virgin binder structures. An example illustrates how selection of compounds from the modified basis set and their amounts can be used to match observed functional group compositions. The objective of this approach is more realistic representation of the molecular interactions between aged asphalt binder structures and those in a waste cooking/motor oil, for example, used to rejuvenate the rheological properties of a binder. Full article

Medium-chain aliphatic compounds bearing oxygen-containing functional groups—such as alcohols, ketones, or carboxylic acids—have attracted increasing attention due to their potential as bioactive agents in pest management. These compounds have demonstrated diverse biocidal properties, including insecticidal, antimicrobial, fungicidal, and nematicidal activities. In this study, the nematicidal potency of three structurally related C9 aliphatic ketones—2-nonanone, 3-nonanone, and 5-nonanone—was evaluated against Bursaphelenchus xylophilus, the pinewood nematode (PWN). These isomeric ketones differ in the position of the carbonyl group, providing a useful model for examining structure–activity relationships (SAR) among positional isomers. The direct-contact bioassays, performed at 1 mg/mL, revealed that 2-nonanone exhibited the highest nematicidal activity, causing 92.3 ± 1.2% mortality on the PWN, followed by 3-nonanone at 80.1 ± 0.8%, while 5-nonanone showed significantly lower activity at 17.1 ± 0.5%. The results suggest a strong dependency of bioactivity on the position of the carbonyl group along the carbon chain. The increasing efficacy from 5- to 2-nonanone suggests that proximity of the carbonyl group to the terminal end may enhance activity, for example, by enhancing membrane interaction or disrupting nematode metabolic processes. These findings underscore the importance of molecule structure analysis in designing effective nematicidal agents and support further investigation into terminally positioned oxygenated medium-carbon chain aliphatic compounds as potential leads. This work highlights that subtle structural differences within homologous series can significantly influence bioactivity and provides a foundation for developing targeted, biodegradable nematicides derived from simple aliphatic frameworks. Full article

The traditional use of iced trash fish (IF) in Chinese mitten crab (Eriocheir sinensis) aquaculture raises sustainability concerns, but the shift to formulated feeds (FF—a commercial compound feed specifically designed to meet nutritional requirements by blending multiple ingredients and containing a balance of nutrients) is often hindered by fears of compromising its prized flavor. This study aimed to comprehensively evaluate whether a commercial formulated feed could effectively replace IF without diminishing flavor quality, hypothesizing that FF would alter the intestinal volatile profile, thereby influencing muscle flavor. Male crabs were fed either IF or FF for eight weeks. Muscle flavor was assessed using sensory evaluation, electronic nose (E-nose), and gas chromatography–ion mobility spectrometry (GC–IMS). Volatile compounds in intestinal chyme were also analyzed by GC–IMS to explore potential transfer mechanisms. The results indicated that crabs fed with FF showed higher sensory scores for sweetness. Additionally, the E-nose analysis revealed a clear separation trend between dietary groups and showed markedly higher sensor response values for aromatic compounds, biogenically derived compounds and Maillard reaction products, sulfur-containing organic compounds, aliphatic hydrocarbons, total volatile organic compounds, alcohols and organic solvents, and alkenes in the FF group compared to the IF group. Thirty-four volatiles were discovered in the muscle. Statistical analysis (independent samples t-test) showed that the FF group exhibited significantly elevated levels of 3-methylbutanal-M, propanal, (E)-2-pentenal, 2,3-pentanedione, and pentan-1-ol-M, whereas the IF group exhibited significantly elevated levels of 2-hexanone, dihydro-2(3H)-furanone, butyl acetate, ethyl 2-methylpropanoate, and phenol (p < 0.05). Fourty-eight volatiles were identified in the intestinal chyme. Propanal and ethyl 2-methylpropanoate were the dominant odor contributors based on correlation network analysis. Strong correlations were identified between the flavor profiles of intestinal chyme and muscle, suggesting a potential transfer or transformation of volatiles. This work provides a scientific basis for optimizing aquafeed formulations to ensure sustainable crab production without sacrificing end-flavor quality. Full article

This study investigates the evolution of the chemical components of kombucha aroma during refrigerated storage. Two preparation methods (MT1 and MT2) were used to produce kombucha from a 1:1 mixture of black and green tea. The bottled beverages were stored at 4 °C for three months, and changes in headspace (HS) volatiles were monitored at different time points using solid-phase microextraction (SPME) and GC-MS. A total of 68 volatile substances were identified, with alcohols, acids, and esters dominating the aroma profile. The study revealed significant changes in flavor composition during cold storage, particularly in the first two weeks, with an increase in the number of esters, acids, ketones and terpenoids, as well as the total amount of esters and alkanols. While some changes contribute to the desirable “cider-like” characteristics, others, like certain volatile acids, aliphatic aldehydes and ketones, are associated with off-flavors. These findings suggest that refrigeration alone is not sufficient to completely inhibit microbial activity in freshly prepared kombucha, highlighting the need for further research to correlate chemical changes with sensory properties to establish optimal organoleptic standards and shelf life. Full article

The depletion of high-grade copper ore reserves in Kazakhstan, coupled with the increasing proportion of refractory ores and the high costs of extraction and processing, necessitates the development of efficient and economically viable technological solutions. In this context, biogeotechnology has gained considerable attention. Recently, alternative approaches based on the use of natural organic compounds—so-called bioreagents—have been introduced into the field of bioleaching. The present study aimed to investigate the effect of amino acids, aliphatic alcohols, and alcohol-based industrial by-products, used as bioadditives, on the bioleaching of copper. The results demonstrated that the influence of amino acids on copper bioleaching decreased in the following order: glycine > leucine > cysteine > histidine > asparagine. Furthermore, the addition of fusel oils, a mixture of aliphatic alcohols, to the bioleaching pulp enhanced copper recovery, achieving extraction efficiencies exceeding 90%. Full article

The NAD⁺-dependent alcohol dehydrogenase AdhB from Aromatoleum aromaticum EbN1 belongs to family III of Fe-dependent alcohol dehydrogenases. It was recombinantly produced in Escherichia coli and biochemically characterized, showing activity only with ethanol or n-propanol. The enzyme contained substoichiometric amounts of Fe, Zn, and Ni and a yet unidentified nucleotide-like cofactor, as indicated by mass spectrometric data. As suggested by its narrow substrate spectrum and complementation of a related species to growth on ethanol, the most probable physiological function of AdhB is the oxidation of short aliphatic alcohols such as ethanol or n-propanol. The enzyme also exhibits a very high tolerance to ethanol and n-propanol, showing moderately substrate-inhibited Michaelis–Menten kinetics up to concentrations of 20% (v/v). AdhB can also be applied biotechnologically to convert acetate to ethanol in coupled enzyme assays with the tungsten enzyme aldehyde oxidoreductase, showing activity with either another aldehyde or pre-reduced benzyl viologen as electron donors. Full article