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The occurrence of hyperuricemia (HUA; elevated serum uric acid) in athletes are relatively high despite that exercise can potentially reduce the risk of developing this condition. Although recent studies have shown the beneficial properties of DAG in improving overall metabolic profiles, a comprehensive understanding on the effect of DAG in modulating HUA in athletes are still lacking. In this study, we leveraged combinatorial lipidomics and metabolomics to investigate the effect of replacing TAG with DAG in the diet of athletes with HUA. A total of 1074 lipids and metabolites from 94 classes were quantitated in serum from 33 athletes, who were categorized into responders and non-responders based on whether serum uric acid levels returned to healthy levels after the DAG diet intervention. Lipidomics and metabolomics analyses revealed lower levels of xanthine and uric acid in responders, accompanied by elevated plasmalogen phosphatidylcholines and diminished acylcarnitine levels. Our results highlighted the mechanisms behind how DAG diet circumvented the risk and effects associated with high uric acid via lowered triglycerides at baseline influencing the absorption of DAG resulting in decline in ROS and uric acid production, increased phospholipid levels associated with reduced p-Cresol metabolism potentially impacting on intestinal excretion of uric acid as well as improved ammonia recycling contributing to decreased serum uric acid levels in responders. These observed alterations might be suggestive that successful implementation of DAG diet can potentially minimize the likelihood of a potential vicious cycle occurring in a high uric acid, elevated ROS and impaired mitochondrial metabolism environment.
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Pancreatic cancer (PC) is a highly aggressive malignancy with a poor prognosis, making early diagnosis crucial for improving patient outcomes. While the gut microbiome, including bacteria and viruses, is believed to be essential in cancer pathogenicity, the potential contribution of the gut virome to PC remains largely unexplored. In this study, we conducted a comparative analysis of the gut viral compositional and functional profiles between PC patients and healthy controls, based on fecal metagenomes from two publicly available data sets comprising a total of 101 patients and 82 healthy controls. Our results revealed a decreasing trend in the gut virome diversity of PC patients with disease severity. We identified significant alterations in the overall viral structure of PC patients, with a meta-analysis revealing 219 viral operational taxonomic units (vOTUs) showing significant differences in relative abundance between patients and healthy controls. Among these, 65 vOTUs were enriched in PC patients, and 154 were reduced. Host prediction revealed that PC-enriched vOTUs preferentially infected bacterial members of Veillonellaceae, Enterobacteriaceae, Fusobacteriaceae, and Streptococcaceae, while PC-reduced vOTUs were more likely to infect Ruminococcaceae, Lachnospiraceae, Clostridiaceae, Oscillospiraceae, and Peptostreptococcaceae. Furthermore, we constructed random forest models based on the PC-associated vOTUs, achieving an optimal average area under the curve (AUC) of up to 0.879 for distinguishing patients from controls. Through additional 10 public cohorts, we demonstrated the reproducibility and high specificity of these viral signatures. Our study suggests that the gut virome may play a role in PC development and could serve as a promising target for PC diagnosis and therapeutic intervention. Future studies should further explore the underlying mechanisms of gut virus-bacteria interactions and validate the diagnostic models in larger and more diverse populations.
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Heces , Microbioma Gastrointestinal , Metagenómica , Neoplasias Pancreáticas , Viroma , Humanos , Neoplasias Pancreáticas/virología , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/microbiología , Microbioma Gastrointestinal/genética , Metagenómica/métodos , Heces/virología , Heces/microbiología , Virus/aislamiento & purificación , Virus/genética , Virus/clasificación , Metagenoma , Bacterias/aislamiento & purificación , Bacterias/clasificación , Bacterias/genética , Persona de Mediana Edad , Masculino , Femenino , Anciano , Estudios de Casos y ControlesRESUMEN
BACKGROUND: Network latency is the most important factor affecting the performance of telemedicine. The aim of the study is to assess the feasibility and efficacy of a novel network latency management system in 5G telesurgery. METHODS: We conducted 20 telesurgery simulation trials (hitching rings to columns) and 15 remote adrenalectomy procedures in the 5G network environment. Telemedicine Network Latency Management System and the traditional "Ping command" method (gold standard) were used to monitor network latency during preoperative simulated telesurgery and formal telesurgery. We observed the working status of the Telemedicine Network Latency Management System and calculated the difference between the network latency data and packet loss rate detected by the two methods. In addition, due to the lower latency of the 5G network, we tested the alert function of the system using the 4G network with relatively high network latency. RESULTS: The Telemedicine Network Latency Management System showed no instability during telesurgery simulation trials and formal telesurgery. After 20 telesurgery simulation trials and 15 remote adrenalectomy procedures, the p-value for the difference between the network latency data monitored by the Telemedicine Network Latency Management System and the "Ping command" method was greater than 0.05 in each case. Meanwhile, the surgeons reported that the Telemedicine Network Latency Management System had a friendly interface and was easy to operate. Besides, when the network latency exceeded a set threshold, a rapid alarm sounded in the system. CONCLUSION: The Telemedicine Network Latency Management System was simple and easy to operate, and it was feasible and effective to use it to monitor network latency in telesurgery. The system had an intuitive and concise interface, and its alarm function increased the safety of telesurgery. The system's own multidimensional working ability and information storage capacity will be more suitable for telemedicine work.
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Robótica , Cirujanos , Telemedicina , Humanos , Robótica/métodos , Estudios de Factibilidad , Telemedicina/métodosRESUMEN
AIM: To evaluate and summarize the available evidence on the prevention and management of nasogastric aspiration in critically ill patients to inform the development of evidence-based clinical practice. DESIGN: This study was an evidence summary according to the evidence summary reporting standard of the Fudan University Center for Evidence-Based Nursing. METHOD: According to the '6S' model of evidence resources, evidence on the prevention and management of aspiration in critically ill patients on nasogastric feeding was retrieved, including clinical decision-making, best practices, guidelines, evidence summaries, expert consensus and systematic evaluations. DATA: UpToDate, BMJ Best Practice, JBI, National Guideline Clearing-house, Guidelines International Network, Scottish Intercollegiate Guidelines Network, National Institute for Health and Care Excellence, Registered Nurses Association of Ontario, Yi Mai tong Guidelines Network, the Cochrane Library, PubMed, Web of Science, Embase, OVID, Sinomed, CNKI, Wan Fang database. The search period was from January 2013 to June 2023. RESULTS: We included a total of 30 high-quality articles and summarized 36 pieces of evidence from them. These pieces of evidence covered 11 dimensions of multidisciplinary management, aspiration risk assessment, tube location, nutritional infusion management, position management, airway management, and oral hygiene. The level of evidence in the study was predominantly level 1 and level 5, with 27 pieces of evidence recommended as 'strong' and 9 pieces of evidence recommended as 'weak'. CONCLUSION: This study summarizes 36 pieces of evidence on preventing and managing aspiration in critically ill patients with nasogastric feeding. But the characteristics of hospitals should be considered in the application of future evidence. IMPACT: Aspiration is the most serious complication during nasogastric feeding, which seriously affects the prognosis of patients. Preventing and managing aspiration in nasogastric patients has proven to be a challenging clinical problem. This study summarized 36 pieces of best evidence in 11 dimensions, including multidisciplinary team, assessment and identification, line position, feeding management, and so on. The implementation of these evidences is conducive to standardizing the operation behaviour of nasogastric feeding in clinical medical staff and reducing the occurrence of aspiration. REPORTING METHOD: This research followed the evidence summary reporting specifications of the Fudan University Center for Evidence-based Nursing. TRIAL REGISTRATION: The registration number is 'ES20221368'.
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The carbon mitigation response encompasses a variety of strategies aimed at mitigating greenhouse gas emissions resulting from human activities. These measures are crafted to address the challenges posed by climate change and facilitate the transition of businesses towards a low-carbon paradigm. Leveraging the analytical outcomes of the extended STIRPAT model and the PSO-BP prediction model, this paper suggests countermeasures for reducing carbon emissions in China's metal smelting industry. The overarching objective is to contribute to China's attainment of the "dual carbon objectives." The study identifies key factors influencing carbon emissions in the metal smelting industry, ranked in descending order of sensitivity: population, coal consumption, urbanization rate, total metal production, carbon intensity, proportion of secondary industry, and GDP per capita. Results from three established scenarios-namely, low carbon, standard, and high carbon-indicate a consistent decline in carbon emissions from China's metal smelting industry over the next 15 years. This research not only enhances the findings of existing studies on carbon emissions in the metal smelting sector but also introduces an innovative approach to carbon emission reduction within China's metal smelting industry.
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Carbono , Gases de Efecto Invernadero , Humanos , Carbono/análisis , Dióxido de Carbono/análisis , Carbón Mineral , Cambio Climático , Desarrollo Económico , ChinaRESUMEN
Activation of fatty acids as acyl-adenylates by fatty acid-AMP ligase (FAAL) is a well-established process contributing to the formation of various functional natural products. Enzymatic characterization of FAALs is pivotal for unraveling both the catalytic mechanism and its role in specific biosynthetic pathways. In this study, we recombinantly expressed and characterized a novel FAAL derived from marine Pseudoalteromonas citrea (PcFAAL). PcFAAL was a cold-adapted neutral enzyme, demonstrating optimal activity at 30 °C and pH 7.5. Notably, its specific activity relied on the presence of Mg2+; however, higher concentrations exceeding 10 mM resulted in inhibition of enzyme activity. Various organic solvents, especially water-immiscible organic solvents, demonstrated an activating effect on the activity of PcFAAL on various fatty acids. The specific activity exhibited a remarkable 50-fold increase under 4% (v/v) n-hexane compared to the aqueous system. PcFAAL displayed a broad spectrum of fatty acid substrate selectivity, with the highest specific activity for octanoic acid (C8:0), and the catalytic efficiency (kcat/Km) for octanoic acid was determined to be 1.8 nM-1·min-1. Furthermore, the enzyme demonstrated biocatalytic promiscuity in producing a class of N-acyl amino acid natural products, as verified by LC-ESI MS. Results indicated that the PcFAAL exhibits promiscuity towards 10 different kinds of amino acids and further demonstrated their potential value in the biosynthesis of corresponding functional N-acyl amino acids.
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It is important to eliminate the fishy odor and improve the aroma quality of seafood. In this study, the Saccharina japonica (S. japonica) seedling, which is a new food material, was investigated for the effects of fermentation with Saccharomyces cerevisiae (S. cerevisiae) through sensory evaluation, GC-MS, and odor activity value (OAV) analysis. GC-MS analysis revealed the presence of 43 volatile compounds in the unfermented S. japonica seedling, with 1-octen-3-ol, hexanal, and trans-2,4-decadienal identified as the main contributors to its fishy odor. After fermentation with S. cerevisiae, 26 volatile compounds were identified in the S. japonica seedling. Notably, the major malodorous fish compounds, including 1-octen-3-ol, hexanal and trans-2,4-decadienal, were no longer present. The results indicate that fermentation with S. cerevisiae is an effective method for removing fishy malodor compounds and enhancing the volatile components with fruity, sweet, green, and floral notes in the Saccharina japonica seedling. This process facilitates the elimination of fishy malodor and enhance the fruity, sweet, green, and floral notes of S. japonica seeding and other seaweeds.
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Urothelial carcinoma (UC) with testicular metastasis is extremely rare, and its modes of metastasis, prognosis, and treatment are unclear. In this report, we present an extraordinarily rare case of testicular metastasis arising from UC 8 years after surgery. The patient underwent left orchiepididymectomy and received immunotherapy postoperatively. After a 6-month follow-up, there were no signs of recurrence. Moreover, the clinical characteristics, metastasis pattern, and treatment plan were also summarized based on 14 earlier reported cases of UC with testicular metastasis.
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Recent explorations into rice bran oil (RBO) have highlighted its potential, owing to an advantageous fatty acid profile in the context of health and nutrition. Despite this, the susceptibility of rice bran lipids to oxidative degradation during storage remains a critical concern. This study focuses on the evolution of lipid degradation in RBO during storage, examining the increase in free fatty acids (FFAs), the formation of oxylipids, and the generation of volatile secondary oxidation products. Our findings reveal a substantial rise in FFA levels, from 109.55 to 354.06 mg/g, after 14 days of storage, highlighting significant lipid deterioration. Notably, key oxylipids, including 9,10-EpOME, 12,13(9,10)-DiHOME, and 13-oxoODE, were identified, with a demonstrated positive correlation between total oxylipids and free polyunsaturated fatty acids (PUFAs), specifically linoleic acid (LA) and α-linolenic acid (ALA). Furthermore, the study provides a detailed analysis of primary volatile secondary oxidation products. The insights gained from this study not only sheds light on the underlying mechanisms of lipid rancidity in rice bran but also offers significant implications for extending the shelf life and preserving the nutritional quality of RBO, aligning with the increasing global interest in this high-quality oil.
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Lipidómica , Lipólisis , Ácidos Grasos , Ácidos Grasos no Esterificados , Ácido Linoleico , Aceite de Salvado de ArrozRESUMEN
Benzophenone-3 (BP-3) is a commonly used ultraviolet absorber that has the potential to accumulate in organisms, leading to toxicity. Benzophenone-8 (BP-8) is one of the major metabolites of BP-3. In this study, zebrafish were exposed to different concentrations of BP-3 and BP-8 (1 µg/L, 30 µg/L, and 300 µg/L) to investigate their accumulation and toxic effects in various tissues, including zebrafish brain, gut, and liver. The analysis focused on neurotoxicity, oxidative damage, inflammation, and gene expressions. The results showed that both BP-3 and BP-8 accumulated in the tissues, with the highest concentration observed in the gut, followed by the liver and brain. BP-8 exhibited a stronger ability to accumulate. In the brain, exposure to 1 µg/L of BP-3 and BP-8 promoted cortisol production, while higher exposures (30 µg/L and 300 µg/L) inhibited acetylcholinesterase activity and suppressed cortisol production. In the gut, both BP-3 and BP-8 exposures disrupted oxidative stress, inflammatory immunity, and apoptosis functions. In the liver, BP-3 and BP-8 affected hepatic metabolism, oxidative stress, apoptosis, and inflammatory immunity. Comparing gene expression in the brain, gut, and liver, it was found that BP-3 and BP-8 had a lower effect on gene expression in the brain, while the effect on the gut and liver was significantly higher. BP-8 generally had a higher effect than BP-3, which aligns with the observed accumulation pattern. These findings provide valuable insights for the risk assessment of BP-3 and BP-8 in the aquatic environment.
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Contaminantes Químicos del Agua , Pez Cebra , Animales , Pez Cebra/metabolismo , Acetilcolinesterasa/metabolismo , Hidrocortisona , Contaminantes Químicos del Agua/toxicidad , Benzofenonas/toxicidadRESUMEN
Rice bran, recognized for its rich lipids and health-beneficial bioactive compounds, holds considerable promise in applications such as rice bran oil production. However, its susceptibility to lipid hydrolysis and oxidation during storage presents a significant challenge. In response, we conducted an in-depth metabolic profiling of rice bran over a storage period of 14 days. We focused on the identification of bioactive compounds and functional lipid species (25 acylglycerols and 53 phospholipids), closely tracking their dynamic changes over time. Our findings revealed significant reductions in these lipid molecular species, highlighting the impact of rancidity processes. Furthermore, we identified 19 characteristic lipid markers and elucidated that phospholipid and glycerolipid metabolism were key metabolic pathways involved. By shedding light on the mechanisms driving lipid degradation in stored rice bran, our study significantly advanced the understanding of lipid stability. These information provided valuable insights for countering rancidity and optimizing rice bran preservation strategies.
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Lipidómica , Oryza , Hidrólisis , Oxidación-Reducción , Fosfolípidos , Lipólisis , Aceite de Salvado de ArrozRESUMEN
In the pursuit of reducing oil separation in peanut butter, oleogels synthesized from diacylglycerol (DAG)-rich peanut oils, using glycerol monostearate (GMS) as the gelator, were examined as alternative stabilizers. In comparison to triacylglycerol (TAG)-rich peanut oils, the DAG oil-based oleogels exhibited better oil-binding capacities across increasing GMS concentrations. Intriguingly, thermal and rheological assessments pointed to a weaker network structure in DAG oil oleogels, as evidenced by their lower crystallization temperatures and reduced viscoelastic parameters (G' and G''). Insight from infrared spectroscopy revealed that this could stem from heightened intermolecular hydrogen bonding between the DAG oil and the gelator. When applied to peanut butter, DAG oil oleogels demonstrated efficacy in minimizing oil separation. Extended storage trials affirmed the long-term stability of peanut butter formulations incorporating these oleogels. Furthermore, sensory evaluations by panelists underscored favorable impressions, suggesting potential consumer acceptance. Overall, this study illuminates the promising role of DAG oleogels as effective, alternative stabilizers in peanut butter formulations.
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Arachis , Diglicéridos , Aceites , Compuestos Orgánicos/químicaRESUMEN
Nervonic acid (NA) is a monounsaturated fatty acid vital for brain health and is of emerging importance in various industrial applications, including therapeutics, food, and cosmetics. Given the growing demands of the food and pharmaceutical industries, there's a pressing need for high-purity NA. Previously, NA constituents in plant seed oils were chemically transformed into nervonic acid ethyl ester (NAEE) to facilitate extraction from seed oils. In this study, we present an enzymatic approach to convert NA constituents in Malania oleifera seed oil to NAEE. Combined with the utilization of the semi-preparative chromatography, we achieved a remarkable purity of 97.52% NAEE. Compared to conventional chemical preparations characterized by multiple steps, prolonged processing times, and low yields and purities, our enzymatic method stands out as a more efficient and advantageous alternative. On top of that, this innovative approach is environmentally friendly and circumvents health and safety issues associated with chemical processes.
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Ácidos Grasos Monoinsaturados , Aceites de Plantas , Aceites de Plantas/química , Ácidos Grasos Monoinsaturados/análisis , Semillas/química , Ácidos Grasos/análisisRESUMEN
Three-liquid-phase systems (TLPSs) are novel interfacial enzymatic reaction systems that have been successfully applied in many valuable reactions. However, these systems are suitable only for hydrolysis reactions and not for more widely used esterification reactions. Surprisingly, our recent research revealed that two water-insoluble substrates (ß-sitosterol and conjugated linoleic acid) could be rapidly esterified in this system. The initial rate of the esterification reaction in the TLPS based on sodium citrate was enhanced by approximately 10-fold relative to that in a traditional water/n-hexane system. The special emulsion structure (S/W1/W2 emulsion) formed may be vital because it not only provides a larger reaction interface but also spontaneously generates a middle phase that might regulate water activity to facilitate esterification. Furthermore, the lipase-enriched phase could be reused at least 8 times without significant loss of catalytic efficiency. Therefore, this TLPS is an ideal enzymatic esterification platform for ester synthesis because it is efficient, convenient to use, and cost-effective.
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Enzymatic oxygenation of various cyclic ketones into lactones via Baeyer-Villiger monooxygenases (BVMOs) could provide a promising route for synthesizing fragrances and pharmaceutical ingredients. However, unsatisfactory catalytic activity and thermostability restricted their applications in the pharmaceutical and food industries. In this study, we successfully improved the catalytic activity and thermostability of a Baeyer-Villiger monooxygenase (OgBVMO) from Oceanicola granulosus by reshaping the binding pocket. As a result, mutant OgBVMO-Re displayed a 1.0- to 6.4-fold increase in the activity toward branched cyclic ketones tested, accompanied by a 3 °C higher melting point, and a 2-fold longer half-life time (t1/2 (45 °C)). Molecular dynamics simulations revealed that reshaping the binding pocket achieved strengthened motion correlation between amino acid residues, appropriate size of the substrate-binding pocket, beneficial surface characteristics, lower energy barriers, and shorter nucleophilic distance. This study well demonstrated the trade-off between the enzyme activity and thermostability by reshaping the substrate-binding pocket, paving the way for further engineering other enzymes.
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Estabilidad de Enzimas , Oxigenasas de Función Mixta , Oxigenasas de Función Mixta/química , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Sitios de Unión , Cinética , Biocatálisis , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Especificidad por Sustrato , Simulación de Dinámica Molecular , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Calor , Cetonas/química , Cetonas/metabolismoRESUMEN
The objective of this work was to completely replace margarine with peanut diacylglycerol oil/ethyl cellulose-glycerol monostearate oleogel (DEC/GMS) oleogel, and evaluate its effect on starch digestibility of cakes. The in vitro digestibility analysis demonstrated that the DEC/GMS-6 cake exhibited a 26.36% increase in slowly digestible starch (SDS) and resistant starch (RS) contents, compared to cakes formulated with margarine. The increased SDS and RS contents might mainly be due to the hydrophobic nature of OSA-wheat flour, which could promote the formation of lipid-amylose complexes with GMS and peanut diacylglycerol oil. XRD pattern suggested that the presence of GMS in DEC-based oleogels facilitated the formation of lipid-amylose complexes. The DSC analysis revealed that the addition of GMS resulted in a significant increase in gelatinization enthalpy, rising from 249.7 to 551.9 J/g, which indicates an improved resistance to gelatinization. The FTIR spectra indicated that the combination of GMS could enhance the hydrogen bonding forces and short-range ordered structure in DEC-based cakes. The rheological analysis revealed that an increase in GMS concentration resulted in enhanced viscoelasticity of DEC-based cake compared to TEC-based cakes. The DEC-based cakes exhibited a more satisfactory texture profile and higher overall acceptability than those of TEC-based cakes. Overall, these findings demonstrated that the utilization of DEC-based oleogel presented a viable alternative to commercial margarine in the development of cakes with reduced starch digestibility.
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The limited availability of phospholipase A1 (PLA1) has posed significant challenges in enzymatic degumming. In this study, a novel PLA1 (UM2) was introduced to address this limitation, which had a unique thermo-responsive ability to switch phospholipase and lipase activities in response to temperature variations. Remarkably, UM2 displayed an unprecedented selectivity under optimized conditions, preferentially hydrolyzing phospholipids over triacylglycerols-a specificity superior to that of commercial PLA1. Moreover, UM2 demonstrated high efficiency in hydrolyzing phospholipids with a predilection for phosphatidylcholine (PC) and phosphatidylethanolamine (PE). A practical application of UM2 on crude flaxseed oil led to a dramatic reduction in phosphorus content, plummeting from an initial 384.06 mg/kg to 4.38 mg/kg. Broadening its industrial applicability, UM2 effectively performed enzymatic degumming for other distinct crude vegetable oils with a unique phospholipid composition. Collectively, these results highlighted the promising application of UM2 in the field of oil degumming.
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Fosfolipasas A1 , Fosfolípidos , Fosfolipasas A1/química , Fosfolipasas A1/metabolismo , Fosfolípidos/química , Fosfolípidos/metabolismo , Hidrólisis , Aceite de Linaza/química , Lipasa/química , Lipasa/metabolismo , Calor , Estabilidad de Enzimas , Biocatálisis , Especificidad por Sustrato , Aceites de Plantas/química , TemperaturaRESUMEN
Conventional wastewater treatment methods cannot completely remove the ultraviolet (UV) filters or dissolved organic matter. The transformation characteristics of these substances during chlorination disinfection and the varying species-specific toxicities of their combinations remain unclear. Here, Daphnia magna and zebrafish were exposed to benzophenone-3 (BP-3) and humic acid (HA) before and after chlorination disinfection. The results from chemical indicators showed that chlorination treatment decreased UV254 values and changed the intensity of parallel factors in three-dimensional fluorescence. Based on chemical analysis, the chlorine concentration and chlorination time for the toxicity experiments were set at 5 mg/L and 6 h, respectively. Exposure to HA and BP-3 before and after chlorination decreased the heart rate (by 1.37-28.12 %) in both species. However, species-specific responses, including survival rate, swimming distance, and expression of genes related to neurodevelopment, growth, and oxidative stress, were induced by chlorination. Chlorination reduced the impact of HA exposure but worsened the effects of HA and BP-3 co-exposure on D. magna. However, in zebrafish, the toxic effects intensified in most of the exposure groups after chlorination. Correlation analysis showed that the parallel factors of three-dimensional fluorescence were correlated with toxic effects on zebrafish, whereas UV254 was more significantly correlated with toxic effects on D. magna. This study provides insights into the combined toxicity of UV filters and dissolved organic matter in different aquatic organisms during chlorination, which is useful for risk control and optimization of the chlorination process.
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Benzofenonas , Desinfección , Halogenación , Sustancias Húmicas , Contaminantes Químicos del Agua , Animales , Benzofenonas/toxicidad , Cloro/toxicidad , Cloro/química , Daphnia magna/efectos de los fármacos , Daphnia magna/fisiología , Desinfección/métodos , Frecuencia Cardíaca/efectos de los fármacos , Sustancias Húmicas/toxicidad , Rayos Ultravioleta , Contaminantes Químicos del Agua/toxicidad , Purificación del Agua/métodos , Pez Cebra/fisiologíaRESUMEN
The positional distribution of palmitic acid (PA) in human milk fat substitutes (HMFSs) plays a pivotal role in mimicking the nutritional profile of human milk fat for nourishing non-breastfed infants. This study innovatively introduced a streamlined enzymatic process for preparing HMFSs rich in sn-2 PA using palm stearin, a PA-rich source without the necessity for positional distribution of PA. The initial step involved enhancing the sn-2 PA concentration through enzymatic interesterification using Lipase UM1, which exhibited superior catalytic efficiency than Novozym 435. This process increased the sn-2 PA level from 40.98 % to 64.51 %. Subsequently, acidolysis was employed to reduce PA levels by replacing PA at sn-1,3 positions using sn-1,3-regioselective lipases. The PA content decreased from 60.64 % to 26.73 %, simultaneously raising the relative sn-2 PA concentration to 71.57 %, meeting the benchmarks for HMFSs. This study establishes a robust conceptual framework for the prospective industrial synthesis of HMFSs.