Search Results (41)

The enzymatic production of fatty acid ethyl esters (FAEEs) and xylose fatty acid esters (XFAEs) from soybean oil deodorizer distillate (SODD) was investigated using a hydroesterification strategy. SODD was enzymatically hydrolyzed, and the glycerol-free fraction was esterified with either xylose or ethanol. Free lipase from Pseudomonas fluorescens (PFL) yielded 84 wt% of free fatty acids (FFAs) production (with approximately 15% FFAs remaining as glycerides) after 48 h, using a SODD-to-water mass ratio of 1:4 and an enzyme loading of 5 wt% (based on oil mass). In the synthesis of FAEEs, free Eversa Transform converted approximately 82% of the FFAs into FAEEs after 48 h, using an ethanol-to-FFA molar ratio of 3.64:1 and an enzyme loading of 8.36% (w/v). For the synthesis of XFAEs, commercially immobilized lipases from Thermomyces lanuginosus (TLL-T2-150) and Pseudomonas fluorescens (IMMAPF-T2-150) were employed. These commercial lipase preparations are available in their immobilized form on Immobead T2-150. TLL-T2-150 resulted in a lower degree of xylose ester formation (80.20%) compared to IMMAPF-T2-150 (89.20%) after 24 h, using an FFA-to-xylose molar ratio of 5 in ethyl-methyl-ketone (xylose concentration of 7 mmol L⁻¹) and an enzyme loading of 0.5% (w/v). However, TLL-T2-150 consumed more FFAs, suggesting a higher degree of xylose esterification. The final reaction mixture containing XFAEs obtained with this biocatalyst exhibited suitable emulsifying properties. A Life Cycle Assessment (LCA) revealed that the enzymatic hydroesterification process offers a sustainable route for FAEEs and XFAEs production, with configurations using free PFL in hydrolysis and IMMAPF-T2-150 in esterification showing the lowest environmental impacts due to higher catalytic efficiency. The findings point to a clear environmental edge in using SODD for ester production, offering a cleaner alternative to standard methods and making better use of a renewable resource. Full article

Substance use during pregnancy is an increasingly important yet under-recognized threat to maternal and child health. This narrative review synthesizes the current evidence available on the epidemiology, pathophysiology, clinical management, and policy landscape of prenatal exposure to alcohol, tobacco, opioids, benzodiazepines, cocaine, cannabis, methamphetamines, and other synthetic drugs. All major psychoactive substances readily cross the placenta and can remain detectable in breast milk, leading to a shared cascade of obstetric complications (hypertensive disorders, placental abruption, pre-term labor), fetal consequences (growth restriction, structural malformations), and neonatal morbidities such as neonatal abstinence syndrome and sudden infant death. Mechanistically, trans-placental diffusion, oxidative stress, inflammatory signaling, and placental vascular dysfunction converge to disrupt critical neuro- and cardiovascular developmental windows. Early identification hinges on the combined use of validated screening questionnaires (4 P’s Plus, CRAFFT, T-ACE, AUDIT-C, TWEAK) and matrix-specific biomarkers (PEth, EtG, FAEE, CDT), while effective treatment requires integrated obstetric, addiction, and mental health services. Medication for opioid use disorders, particularly buprenorphine, alone or with naloxone, confers superior neonatal outcomes compared to methadone and underscores the value of harm-reducing non-punitive care models. Public-health strategies, such as Mexico’s “first 1 000 days” framework, wrap-around clinics, and home-visiting programs, demonstrate the potential of multisectoral interventions, but are hampered by structural inequities and punitive legislation that deter care-seeking. Research gaps persist in polysubstance exposure, culturally tailored therapies, and long-term neurodevelopmental trajectories. Multigenerational, omics-enabled cohorts, and digital longitudinal-care platforms represent promising avenues for closing these gaps and informing truly preventive perinatal health policies. Full article

The most commonly used homogeneous catalyst for fatty acid esterification is a corrosive sulphuric acid. However, this requires costly investment in non-corrosive equipment, presents a safety risk, is time consuming, and increases effluent generation. In this study, inorganic 3D heteroborane cluster strong acids are employed for the first time as homogeneous catalysts. Three novel isomeric tetrachlorido and tetrabromido derivatives of 3,3′-commo-bis[undecahydrido-closo-1,2-dicarba-3-cobaltadodecaborate](1−) [1⁻] were synthesised and fully characterised using a range of analytical techniques, including NMR, TLC, HPLC, MS, UV-Vis, melting point (MP), CHN analyses, and XRD. Ultimately, H₃O[8,8′-Cl₂-1⁻] was identified as the most efficient, reusable, and non-corrosive homogeneous catalyst for the esterification of four fatty acids. The reactions are conducted in an excess of alcohol at reflux. The effective absorption of water vapour provided by the molecular sieves maximises acid conversion. The hydrophobic dye Sudan black B was employed as an acid-base indicator to facilitate a comparison of the H₀ acidity function of sulphuric acid and halogenated heteroboranoic acids when dissolved together in methanol. The ²³Na NMR analysis demonstrated that the application of dry methanol resulted in the displacement of Na⁺ ions from zeolite, which subsequently exchanged the H₃O⁺ ions of the acid. This process led to a gradual reduction in the efficiency of the catalysts, particularly with repeated use. The solution to this issue is to regenerate the catalyst on the ion exchanger following each reaction. In contrast to the published methods, our new approach meets 10 of 12 green chemistry principles. Full article

This study provides experimental insights into the liquid–liquid equilibrium (LLE) of a system consisting of fatty acid ethyl ester (FAEE) derived from licuri oil, glycerol, and ethanol, evaluated at various temperatures and standard atmospheric pressures. FAEE was synthesized through transesterification of licuri oil using NaOH as a catalyst. The liquid phase compositions were assessed via titration, and the results were consistent with the solubility curves and overall compositions. Data reliability was confirmed using Hand and Othmer-Tobias correlations, with a determination coefficient (R²) of 1, validating the dependability of the results. The NRTL model was employed to correlate the LLE data, yielding a root-mean-square deviation (RMSD) of approximately 1.20%, signifying a strong correlation with experimental uncertainties. The selectivity (S) and distribution (D) parameters indicated the efficacy of glycerol in the system, with S values exceeding 1 under all conditions tested. This investigation is crucial for biodiesel production, highlighting the potential of licuri oil as a renewable feedstock and the importance of phase equilibrium studies in the separation processes of biodiesel production products. Full article

Throughout the decades, the production, transport, and use of fossil fuels have led to numerous environmental concerns. Crude oil has caused catastrophic accidents after its spillage into the aqueous environment and accumulation on coastal sediments. To tackle this problem in a sustainable manner, researchers have used alternative remediation agents to extract these crude oil spills from the sediments. In this study, the biodiesels fatty acid methyl, ethyl, and butyl esters (FAME, FAEE, and FABE, respectively) were synthesized via transesterification reaction from waste cooking oil and corresponding alcohol in the presence of a catalyst, potassium hydroxide, and used as remediation agents for crude oil extraction. The influence of different experimental conditions on the crude-oil removal efficiency was studied (time of 1, 2, or 4 h; mass ratio of biodiesel to crude oil of 0.5:1, 1:1, or 2:1), with a simulation of coastal effects using a shaker. UV/Vis spectrophotometry was used to determine crude-oil separation efficiency based on the correlation of the residual crude-oil mass fraction and corresponding absorbance. The results show that FAME and FAEE were most effective in the removal of crude oil from sand (removing 88–89%), while FAEE and FABE extracted the most crude oil from gravel (removing 74–77%). Full article

This study aimed to investigate the liquid–liquid equilibrium (LLE) behavior of sesame fatty acid ethyl ester (FAEE) and methyl ester (FAME) in combination with glycerol and the co-solvents ethanol and methanol. FAEE and FAME were produced through the transesterification of mechanically extracted and purified sesame oil, using potassium hydroxide (KOH) as a homogeneous base catalyst. The reactions were conducted in ethanol and methanol to produce FAEE and FAME, respectively. Post-reaction, the products were separated and purified, followed by an analysis of the LLE behavior at 313.15 K and 323.15 K under atmospheric pressure (101.3 kPa). The experimental process for the miscibility analysis utilized a jacketed glass cell adapted for this study. Miscibility limits or binodal curves were determined using the turbidity-point method. Tie lines were constructed by preparing mixtures of known concentrations within the two-phase region, which allowed the phases to separate after agitation. Samples from both phases were analyzed to determine their composition. This study revealed that higher temperatures promoted greater phase separation and enhanced the biodiesel purification process. The NRTL model effectively correlated the activity coefficients with the experimental data, showing good agreement, with a root-mean-square deviation of 3.5%. Additionally, the data quality was validated using Marcilla’s method, which yielded an R² value close to 1. Attraction factors and distribution coefficients were also calculated to evaluate the efficiency of the co-solvents as extraction agents. The findings indicated higher selectivity for methanol than for ethanol, with varying degrees of distribution among the co-solvents. These results offer significant insights into enhancing biodiesel production processes by considering the effects of co-solvents on the LLE properties of mixtures, ultimately contributing to more efficient and cost-effective biodiesel production. Full article

This article describes the results of a comprehensive comparative study of the production of fatty acid ethyl esters (FAEEs) for use as biodiesel in perfect mixing reactors (PMRs) and plug flow reactors (PFRs). The products obtained on a laboratory scale at all stages of the separation and purification of the FAEE phase were analyzed using the FTIR, XRF and GC-MS methods. We compared distillation methods for the separation of stoichiometrically excessive ethanol from the reaction mixture. Neutralization methods with H₂SO₄ solution and carbonation with CO₂ were applied for FAEE phase purification from the catalyst. Emulsions formed during the water flushing stage were analyzed via the optical microscopy method. The optimal conditions of stirring speed and temperature were selected to maintain a high level of FAEE–water phase contact area with minimum phase separation time. The efficiency of the carbonation method for catalyst neutralization in the FAEE phase has been proven, allowing us to consider this method as an alternative to the traditional acid neutralization method. According to the results of experimental studies, we have developed a new high-performance technological scheme for the production of fatty acid esters in PFRs. The synthesis of FAEEs in a stoichiometric excess of ethanol of about 1:50 allowed us to increase the reaction rate and productivity of the synthesis unit after the transition from a PMR to a PFR. The yield of the product amounted to 86.7%. The purified FAEE fraction complied with most EN14214 specifications. Full article

Marine microalgae Schizochytrium sp. have a high content of docosahexaenoic acid (DHA), an omega-3 fatty acid that is attracting interest since it prevents certain neurodegenerative diseases. The obtention of a bioactive and purified DHA fatty acid ester using a whole-integrated process in which renewable sources and alternative methodologies are employed is the aim of this study. For this reason, lyophilized Schizochytrium biomass was used as an alternative to fish oil, and advanced extraction techniques as well as enzymatic modification were studied. Microalgal oil extraction was optimized via a surface-response method using pressurized liquid extraction (PLE) obtaining high oil yields (29.06 ± 0.12%) with a high concentration of DHA (51.15 ± 0.72%). Then, the enzymatic modification of Schizochytrium oil was developed by ethanolysis using immobilized Candida antarctica B lipase (Novozym^® 435) at two reaction temperatures and different enzymatic loads. The best condition (40 °C and 200 mg of lipase) produced the highest yield of fatty acid ethyl ester (FAEE) (100%) after 8 h of a reaction attaining a cost-effective and alternative process. Finally, an enriched and purified fraction containing DHA-FAEE was obtained using open-column chromatography with a remarkably high concentration of 93.2 ± 1.3% DHA. The purified and bioactive molecules obtained in this study can be used as nutraceutical and active pharmaceutical intermediates of marine origin. Full article

The move towards environmentally friendly processing has been a driving force for research into green methods for the extraction of bioactive compounds from plant materials. In this study, a green and efficient process for the extraction of β-carotene from sea buckthorn berries through the simultaneous use of ultrasound and microwave, using a novel green solvent, fatty acid ethyl esters (FAEE), is described. For the same extraction time (45 min), the β-carotene content in the extract was significantly increased (according to ANOVA analysis—p < 0.05) by the simultaneous use of ultrasound and microwave, compared with the separate use of these technologies—an increase of 15 and 89% compared with ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE), respectively. The resulting extract can be used directly, without further purification, as a food supplement because the solvent itself is safe for consumption. Furthermore, FAEE contains omega-3 and omega-6 fatty acids which add to the health benefits of the extract. When β-carotene is extracted from the plant matrix, it is subjected to degradation due to oxidation, but the addition of the antioxidant vitamin E (13 mg/mL of extract) to the extract extends its stability to more than 90 days at room temperature even when exposed to light. The addition of vitamin E also enhances the health benefits of the extract. Full article

The oral consumption of alcohol (ethanol) has a long tradition in humans and is an integral part of many cultures. The causal relationship between ethanol consumption and numerous diseases is well known. In addition to the well-described harmful effects on the liver and pancreas, there is also evidence that ethanol abuse triggers pathological skin conditions, including acne. In the present study, we addressed this issue by investigating the effect of ethanol on the energy metabolism in human SZ95 sebocytes, with particular focus on qualitative and quantitative lipogenesis. It was found that ethanol is a strong trigger for lipogenesis, with moderate effects on cell proliferation and toxicity. We identified the non-oxidative metabolism of ethanol, which produced fatty acid ethyl esters (FAEEs), as relevant for the lipogenic effect—the oxidative metabolism of ethanol does not contribute to lipogenesis. Correspondingly, using the Seahorse extracellular flux analyzer, we found an inhibition of the mitochondrial oxygen consumption rate as a measure of mitochondrial ATP production by ethanol. The ATP production rate from glycolysis was not affected. These data corroborate that ethanol-induced lipogenesis is independent from oxygen. In sum, our results give a causal explanation for the prevalence of acne in heavy drinkers, confirming that alcoholism should be considered as a systemic disease. Moreover, the identification of key factors driving ethanol-dependent lipogenesis may also be relevant in the treatment of acne vulgaris. Full article

The conjugation of phytosterols (PSs) with fatty acids results in producing phytosterol esters (PSEs) characterized by enhanced lipophilicity and improved functional properties of major interest in food and nutraceutical applications. The use of immobilized lipases to catalyze direct transesterification reactions between PSs and plant oils to form PSEs as a green alternative to conventional chemical production methods has attracted interest during the last two decades. The low solubility of PSs in common plant oil triglycerides, typically below 3% at ambient temperatures, remains the main challenge for bringing lipase-catalyzed direct transesterification reactions of PSs and oil triglycerides to commercial scales. This study focuses on the enzymatic synthesis of PSEs starting from solubilized PSs at concentrations of up to 30% wt./wt. of oil mixtures comprising fatty acid ethyl esters (FAEEs), monoglycerides (MGs), diglycerides (DGs), and triglycerides (TGs) as a homogeneous medium for the direct transesterification reaction. The results of this study show for the first time that the addition of FAEEs into the reaction medium results in an alteration of the substrate preference of the enzyme, making MGs the favorite fatty acyl group donors for PSs amongst all other fatty acyl donors present in the reaction system. The proposed new enzymatic route allows starting with high concentrations of solubilized PSs, making the direct transesterification of oil glycerides attractive for the production of PSEs at industrial scales. Full article

In the present work, borage oil (Borago officinalis) was used as the main source of gamma linolenic acid (GLA) to obtain ethyl esters by enzymatic ethanolysis using immobilized enzymes for its application in the food industry. Commercial Thermomyces lanuginosus lipase (TLL) was compared to chemical ethanolysis in alkaline medium. In addition, TLL was immobilized by adsorption on hydrophobic porous support (Octadecyl-Sepabeads^®) to compare the results. Fatty acid ethyl ester (FAEE) yields of both reactions were compared under the same conditions (25 °C and 200 rpm) and analyzed by GC-MS. Moreover, the conversion yield for borage oil ethanolysis catalyzed by TLL immobilized on C18-Sepabeads^® supports was similar to the chemical pathway (93.4% and 99.5%, respectively). When this biocatalyst was used in a solvent-free system (at 40 °C and 200 rpm), it was possible to obtain a high FAEE yield of 84.3% in the first 24 h of reaction. Furthermore, it was possible to re-use the immobilized biocatalyst for the performance of five reaction cycles maintaining 68% of its initial activity. Thus, the use of immobilized enzymes in solvent-free systems is an eco-friendly alternative to obtain GLA ethyl esters for its possible application in cosmetics and food. Full article

The effect of temperature was studied on the synthesis of fatty acid alkyl esters by means of transesterification of waste beef tallow using ethanol and, iso-butanol and 1-butanol at supercritical conditions. These alcohols are proposed for the synthesis of biodiesel in order to improve the cold flow properties of alkyl esters. Alcohol–beef tallow mixtures were fed to a high-pressure high-temperature autoclave at a constant molar ratio of 45:1. Reactions were carried out in the ranges of 310–390 °C and 310–420 °C for ethanol and iso-butanol, respectively; meanwhile, synthesis using 1-butanol was assessed only at 360 °C. After separation of fatty acid alkyl esters, these samples were characterized by nuclear magnetic resonance (NMR) and gas chromatography coupled to mass spectrometry (GC-MS) to quantify yields, chemical composition, and molecular weight. Results indicated that yields enhanced as temperature increased; the maximum yields for fatty acid ethyl esters (FAEEs) were attained at 360 °C, and for fatty acid butyl esters (FABEs) were achieved at 375 °C; beyond these conditions, the alkyl ester yields reached equilibrium. Concerning the physicochemical properties of biodiesel, the predicted cetane number and cloud point were enhanced compared to those of fatty acid methyl esters. Full article

A high-performance and scalable lipase immobilization method using a dipping and jet break-up technique was reported for the production of microcapsule biocatalysts with an entrapped cascade of lipase enzyme. The lipase from Candida antarctica (CALb) recombinant Aspergillus oryzae and from the vegetal of Jatropha curcas L. (var. Sevangel) in Morelos State of Mexico were entrapped by mixing with a sodium alginate biopolymer at different concentrations. The obtained microcapsules were hardened in a CaCl₂ solution, aiming at developing Ca²⁺ alginate microbeads with sizes mostly from 220 to 300 μm. The relationship between the process variables with the shape and size of the alginate drops before and after the gelation was established with aid of optical image analysis. The results showed that a critical Ohnesorge number (Oh) > 0.24 was required to form spherical microencapsulated beads. The biodiesel production via esterification/transesterification reaction was performed using the crude Jatropha curcas L. oil as feedstock in a batch reactor using lipase microcapsules as biocatalysts. Under the optimal reaction condition (ethanol-to-oil mass ratio: 10; water content 9.1 wt%, microencapsulated biocatalyst mass: 5.25 g, reaction temperature: 35 °C, pH of reaction mixture 7.5, stirring force 6 g), an approximately 95% fatty acid ethyl esters (FAEE) yield could be obtained. The biodiesel obtained from this work completely satisfied with the related ASTM D6751 and EN14214 standards. The microencapsulation technique reported herein allows the production of lipase microcapsules on a continuous large scale with the characteristics required for sustainable biofuel production and it can be also applied in other fields such as food processing and the pharmaceutical industry. Full article

Biodiesel has established itself as a renewable fuel that is used in transportation worldwide and is partially or in some cases completely replacing conventional fuels. Chemically, biodiesel is a fatty acid monoalkyl ester (FAAE). Generally, the term biodiesel refers to the fatty acid methyl or ethyl esters (FAME or FAEE). Herein, an overview of the research on the synthesis of FAAE in which the alkyl moiety is a C₃₊ alkyl chain (branched/unbranched) is given. In addition, a comparison of the properties of the aforementioned FAAE with each other, with FAME and FAEE, and with fuel standards is given. The length of the alkyl chain has a major influence on viscosity, while pour point temperatures are generally lower when branched alcohols are used, but the fatty acid part of the molecule also has a major influence. The development of new pathways for the synthesis of higher alcohols from biomass opens a future perspective for the production of long chain FAAE as biofuels, fuel additives, or biolubricants. Due to their properties, FAAEs produced from C₃–C₅ alcohols have the potential to be used as fuels, while all C₃₊ FAAEs can be used as valuable bioadditives, and C₈₊ FAAEs can be used as biolubricants and viscosity improvers. Full article