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1.
Bioresour Bioprocess ; 11(1): 43, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38664309

RESUMO

L-Threonine is an important feed additive with the third largest market size among the amino acids produced by microbial fermentation. The GRAS (generally regarded as safe) industrial workhorse Corynebacterium glutamicum is an attractive chassis for L-threonine production. However, the present L-threonine production in C. glutamicum cannot meet the requirement of industrialization due to the relatively low production level of L-threonine and the accumulation of large amounts of by-products (such as L-lysine, L-isoleucine, and glycine). Herein, to enhance the L-threonine biosynthesis in C. glutamicum, releasing the aspartate kinase (LysC) and homoserine dehydrogenase (Hom) from feedback inhibition by L-lysine and L-threonine, respectively, and overexpressing four flux-control genes were performed. Next, to reduce the formation of by-products L-lysine and L-isoleucine without the cause of an auxotrophic phenotype, the feedback regulation of dihydrodipicolinate synthase (DapA) and threonine dehydratase (IlvA) was strengthened by replacing the native enzymes with heterologous analogues with more sensitive feedback inhibition by L-lysine and L-isoleucine, respectively. The resulting strain maintained the capability of synthesizing enough amounts of L-lysine and L-isoleucine for cell biomass formation but exhibited almost no extracellular accumulation of these two amino acids. To further enhance L-threonine production and reduce the by-product glycine, L-threonine exporter and homoserine kinase were overexpressed. Finally, the rationally engineered non-auxotrophic strain ZcglT9 produced 67.63 g/L (17.2% higher) L-threonine with a productivity of 1.20 g/L/h (108.0% higher) in fed-batch fermentation, along with significantly reduced by-product accumulation, representing the record for L-threonine production in C. glutamicum. In this study, we developed a strategy of reconstructing the feedback regulation of amino acid metabolism and successfully applied this strategy to de novo construct a non-auxotrophic L-threonine producing C. glutamicum. The main end by-products including L-lysine, L-isoleucine, and glycine were almost eliminated in fed-batch fermentation of the engineered C. glutamicum strain. This strategy can also be used for engineering producing strains for other amino acids and derivatives.

2.
Mar Drugs ; 22(4)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38667767

RESUMO

Chitosan (CH) shows great potential as an immunostimulatory feed additive in aquaculture. This study evaluates the effects of varying dietary CH levels on the growth, immunity, intestinal morphology, and antioxidant status of Nile tilapia (Oreochromis niloticus) reared in a biofloc system. Tilapia fingerlings (mean weight 13.54 ± 0.05 g) were fed diets supplemented with 0 (CH0), 5 (CH5), 10 (CH10), 20 (CH20), and 40 (CH40) mL·kg-1 of CH for 8 weeks. Parameters were assessed after 4 and 8 weeks. Their final weight was not affected by CH supplementation, but CH at 10 mL·kg-1 significantly improved weight gain (WG) and specific growth rate (SGR) compared to the control (p < 0.05) at 8 weeks. Skin mucus lysozyme and peroxidase activities were lower in the chitosan-treated groups at weeks 4 and 8. Intestinal villi length and width were enhanced by 10 and 20 mL·kg-1 CH compared to the control. However, 40 mL·kg-1 CH caused detrimental impacts on the villi and muscular layer. CH supplementation, especially 5-10 mL·kg-1, increased liver and intestinal expressions of interleukin 1 (IL-1), interleukin 8 (IL-8), LPS-binding protein (LBP), glutathione reductase (GSR), glutathione peroxidase (GPX), and glutathione S-transferase (GST-α) compared to the control group. Overall, dietary CH at 10 mL·kg-1 can effectively promote growth, intestinal morphology, innate immunity, and antioxidant capacity in Nile tilapia fingerlings reared in biofloc systems.


Assuntos
Ração Animal , Aquicultura , Quitosana , Ciclídeos , Intestinos , Animais , Quitosana/farmacologia , Ciclídeos/crescimento & desenvolvimento , Ciclídeos/imunologia , Ciclídeos/metabolismo , Intestinos/efeitos dos fármacos , Aquicultura/métodos , Suplementos Nutricionais , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Expressão Gênica/efeitos dos fármacos
3.
Vet Sci ; 11(4)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38668438

RESUMO

Agroindustrial by-products constitute an alternative source of feed livestock, and their use contributes to the sustainability of livestock systems and the circular bioeconomy. The effects of replacing cereal (0%, 40%, and 80%) with dehydrated orange pulp (DOP) in the diet of goats on the antioxidant and fatty acid (FA) contents of cheeses were evaluated. For a more suitable understanding of the role of coagulant enzymes in establishing the properties of the cheese, the effect of milk-clotting with animal and vegetable rennet was also analysed. The rennet did not substantially affect the FA or the antioxidant compounds, and the use of DOP did not affect the FA contents. However, the α-tocopherol levels, total phenolic compounds (TPC), and total antioxidant capacity (TAC) in cheeses increased as the percentage of DOP replacing cereals increased. Moreover, the high correlation obtained between the TAC and the TPC (r = 0.73) and α-tocopherol (r = 0.62) contents indicated the important role played by these compounds in improving the antioxidant capacity of the cheese. In conclusion, DOP is a suitable alternative to cereals in the diet of goats and improves the antioxidant status of the cheese produced.

4.
Animals (Basel) ; 14(7)2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38612236

RESUMO

Lard (LD) and Basa fish offal oil (BFO) have similar fatty acid profiles, both containing high contents of saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA). The present study aimed to investigate the efficacy of partial or complete replacement of marine fish oil (MFO, herring oil) by LD or BFO in the diets of tiger puffer. The control diet contained 49.1% crude protein and 9.28% crude lipid content including 6% added MFO. In other diets, 1/3, 2/3, and 3/3 of the added MFO was replaced by LD or BFO, respectively. Each diet was fed to triplicate tanks of juvenile fish (initial body weight, 13.88 g). A 46-day feeding trial was conducted in a flow-through seawater system. Each diet was fed to triplicate 200-L rectangular polyethylene tanks, each of which was stocked with 30 fish. Fish were fed to satiation three times a day. The complete replacement of added MFO (replacing 65% of the total crude lipid) had no adverse effects on fish growth performance in terms of survival (>94%), weight gain (360-398%), feed intake (2.37-3.04%), feed conversion ratio (0.84-1.02), and somatic indices. The dietary LD or BFO supplementation also had marginal effects on fish body proximate composition, biochemical parameters, muscle texture, and water-holding ability, as well as the hepatic expression of lipid metabolism-related genes. Partial (2/3) replacement of added MFO by LD or BFO did not significantly reduce the muscle n-3 LC-PUFA content, indicating the n-3 LC-PUFA sparing effects of SFA and MUFA in LD and BFO. In general, dietary LD or BFO reduced the peroxidation level and led to significant changes in the muscle volatile flavor compound profile, which were probably attributed to the change in fatty acid composition. The results of this study evidenced that LD and BFO are good potential lipid sources for tiger puffer feeds.

5.
Int J Mol Sci ; 25(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38612811

RESUMO

In most cases, the unused by-products of venison, including deer tallow, are disposed of in rendering plants. Deer tallow contains essential fatty acids and can be used to prepare products for everyday food and advanced applications. This work aimed to process deer tallow into hydrolyzed products using microbial lipases. A Taguchi design with three process factors at three levels was used to optimize the processing: amount of water (8, 16, 24%), amount of enzyme (2, 4, 6%), and reaction time (2, 4, 6 h). The conversion of the tallow to hydrolyzed products was expressed by the degree of hydrolysis. The oxidative stability of the prepared products was determined by the peroxide value and the free fatty acids by the acid value; further, color change, textural properties (hardness, spreadability, stickiness, and adhesiveness), and changes at the molecular level were observed by Fourier transform infrared spectroscopy (FTIR). The degree of hydrolysis was 11.8-49.6%; the peroxide value ranged from 12.3 to 29.5 µval/g, and the color change of the samples expressed by the change in the total color difference (∆E*) was 1.9-13.5. The conditions of enzymatic hydrolysis strongly influenced the textural properties: hardness 25-50 N, spreadability 20-40 N/s, and stickiness < 0.06 N. FTIR showed that there are changes at the molecular level manifested by a decrease in ester bonds. Enzymatically hydrolyzed deer tallow is suitable for preparing cosmetics and pharmaceutical matrices.


Assuntos
Cervos , Gorduras , Animais , Hidrólise , Carne , Peróxidos
6.
Heliyon ; 10(7): e27774, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38586419

RESUMO

The ring-shaped anisotropic ferrite magnet with multiple poles boasts significant benefits for brushless DC motors (BDCMs). However, the prevalent production method involves dry magnetic field molding, making it challenging to enhance the magnetic properties. Herein, ferrite powder made from iron oxide, a by-product of the steel industry, is used as the starting material of magnets, and the differences between dry and wet molding approaches on the surface magnetic flux density of a ring-shaped multi-pole anisotropic ferrite magnet are first investigated. ANSYS MAXWELL conducted an initial simulation to achieve the design specifications of the wet molding mold. Following this, the mold was prepared for the fabrication of ring magnets. Compared to magnets prepared via dry molding, those produced through wet molding exhibit a peak surface magnetic flux density of approximately 15.9% higher, demonstrating significant potential for industrial applications and substantial enhancement of the key magnetic properties of wet molded ferrite ring magnets. To achieve increased surface flux density of ring magnets, it is common practice to utilize magnetic powders with greater magnetic properties when molding the magnets. However, this requires a costly mold redesign. In this study, higher surface magnetic flux densities can be achieved for ring magnets by simply adjusting the shape, size and magnetization direction of NdFeB permanent magnets that provide a constant aligned magnetic field in the mold without requiring any alterations to the existing mold's dimensions. The findings of this study could improve the effectiveness of existing motor designs. The usage of ring-shaped multi-pole anisotropic ferrite magnets is anticipated to witness a surge in the coming years, driven by the growth of energy-efficient motors in diverse sectors.

7.
J Econ Entomol ; 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38430932

RESUMO

The utilization of yellow mealworm, Tenebrio molitor (Linnaeus, Coleoptera: Tenebrionidae), for food and feed is gaining interest globally. However, its production is hindered by expensive commercial diets. This study assessed mealworm growth performance, survival, bioconversion, and nutritional composition when fed on wheat bran (WB) with different inclusion levels (25%, 50%, 75%, and 100%) of Irish potato waste (PW). Results indicated that mealworms fed on diets with 25%-75% PW had increased body length and 1-2 times higher weight gain compared to sole WB and PW diets. The survival rate was 93%-94% across all diets. Mealworms fed on WB had a feed conversion ratio of 3.26, while the efficiency of diet conversion increased with PW inclusion levels. Mealworms fed on diets with 75% PW inclusion had the highest crude fat (48%) and energy levels (598 kcal/100 g), while sole WB produced mealworms with the highest crude protein (55%). The acid detergent fiber achieved using 100% WB was 2- to 3-fold higher, but the crude fiber and neutral detergent fiber did not vary significantly. Considerable amounts of lysine (1.6-2 mg/100 g), methionine (0.5-0.7 mg/100 g), leucine (1.4-2 mg/100 g), and threonine (0.8-1 mg/100 g) were achieved in the mealworm larvae. Our findings revealed that cheap agricultural by-products could be successfully used for the mass production of mealworms, substantially contributing to reduced production costs. Further exploration of the nutrient-dense mealworm larvae for the development of novel food and feed products is crucial.

8.
Foods ; 13(5)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38472796

RESUMO

The valorization of milk whey appears to be a promising strategy for managing by-products from dairy food industries, which incur demanding economic costs for treatment and/or disposal. Thanks to its numerous bioactive components, whey is expected to be increasingly incorporated into foods in the future. We investigated the safety of ovine milk whey through in vitro experiments on human primary gingival fibroblast (HGF-1) proliferation and wound healing. Fibroblasts play a crucial role in the repair processes from the late inflammatory phase until the final stages. Cells treated with varying concentrations of ovine whey (0.01%, 0.1%, 1%, and 10%) were able to close wounds more rapidly than vehicle-treated cells. Time- and dose-dependent responses were observed in cell populations exposed to ovine whey. Specifically, wounds treated with 0.1% and 10% milk whey showed better migratory capabilities compared to those treated with 0.01% and 1% milk whey after 24 and 48 h. In addition, ovine milk whey stimulates extracellular matrix deposition, as evidenced by the increasing levels of CD44 antigen density evaluated through FACS analysis, as well as COL1A1 expression measured both via RT-qPCR and immunofluorescence. This phenomenon was particularly evident at concentrations of 0.01% and 10%. Ensuring quality and safety has become a major concern for health authorities in the food industry. Our findings suggest that ovine milk whey is safe and possesses regenerative properties. It facilitates tissue re-establishment following exposure to environmental stress, particularly accelerating gingival wound closure.

9.
Foods ; 13(5)2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38472802

RESUMO

White grape pomace (winery by-product) stabilized by blanching and high hydrostatic pressure has recently been successful at delaying lipid oxidation in burgers. The aim of this study was to investigate whether it can also delay lipid oxidation in dry-cured sausages, and to compare its effect when added at 0.5 and 3% with those of synthetic additives (sodium nitrite and ascorbic acid) and no additives (Control) in lipid and protein oxidation, the instrumental color, the sensory characteristics, and the volatile compounds. The pomace (68.7 ± 7.4 mmol Trolox g-1) was as effective as the additives at preventing lipid oxidation, resulting in values 3.2-3.8 times lower than the Control sausages. However, the pomace was not effective at decreasing the microbial counts, improving the instrumental and sensory color and the volatile compound profile, and decreasing the off-odor and off-flavor developed in the Control sausages. The lack of a detrimental effect of the pomace at 0.5% on the volatile compounds and the sensory characteristics and its benefits to delay lipid oxidation suggest that it might be useful to improve the oxidative stability. Conversely, at 3%, with a detrimental effect on some sensory characteristics and no benefits over the lower dosage, is not advisable.

10.
Plants (Basel) ; 13(5)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38475439

RESUMO

Banana peel (BP) is the primary by-product generated during banana processing which causes numerous environmental issues. This study examines the physical attributes, proximate analysis, glycoarray profiling, antioxidant abilities, and prebiotic activity of BP. The analysis demonstrated that carbohydrates constituted the primary components of BP and the glycoarray profiling indicated that BP contains multiple pectin and hemicellulose structures. BP also contained phenolic compounds, including (+)-catechin and gallic acid, flavonoid compounds, and antioxidant activities. BP demonstrated prebiotic effects by promoting the proliferation of advantageous gut bacteria while inhibiting the growth of harmful bacteria. The prebiotic index scores demonstrated that BP exhibited a greater capacity to promote the growth of beneficial bacteria in comparison to regular sugar. The study demonstrated the potential of the BP as a valuable source of dietary fibre, bioactive compounds, and prebiotics. These components have beneficial characteristics and can be utilised in the production of food, feed additives, and functional food.

11.
Int J Biol Macromol ; 266(Pt 1): 131271, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38556239

RESUMO

Yerba mate industrial processing produces tons of powder as a by-product, this yerba mate powder (YMP) is an excellent source of biomass to develop biodegradable materials. Cassava starch modified with 1,2,3,4-butane tetracarboxylic acid (BA) in the presence of sodium propionate as a catalyst is an eco-friendly option to obtain bioadhesives. This work aimed to develop sustainable laminates from starch-based adhesives and yerba mate powder and to study their physico-chemical, structural, and mechanical properties. Blends of bioadhesive and YMP were prepared (1:1, adhesive:YMP). Monolayer materials were obtained by thermo-compression and later assembled with adhesive to obtain bilayer laminates. Bioadhesive was able to bind the yerba mate by-product fibers, as evidenced by SEM microstructure analysis, the interactions of adhesive:substrate were elucidated by ATR-FTIR and supported by chemometrics analysis. The incorporation of the catalyst decreased the rugosity of materials and their mechanical performance was improved by the action of both acid concentration and catalyst presence, requiring higher energy for puncture. Thus, it was feasible to obtain mono and bilayer laminates as an eco-compatible alternative for the design of sustainable tray-like materials based on the industrial by-product of yerba mate.

12.
Foods ; 13(6)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38540872

RESUMO

Fermented fish bone residue (FFBR) is an underused by-product of the industrial-scale production of fermented fish sauce. Subjecting FFBR to proper alkaline treatment can transform FFBR into biocalcium, which can be added to fish emulsion sausage (FES) to increase its calcium content. This study comprised two experiments. First, we aimed to find the most suitable alkaline treatment conditions for preparing biocalcium from FFBR. Alkaline treatments combining three sodium hydroxide (NaOH) concentrations (0%, 3%, and 6%) and three soaking times (0, 1, and 2 h) were tested. Quality parameters of alkaline-treated biocalcium (crude protein, crude fat, ash content, calcium, phosphorus, crude fiber, salt content, CIE color values, morphology of biocalcium particles, and the intensity of the fermented fish smell) were assessed. Second, we fortified FES with the properly treated biocalcium (0, 12, 24, or 36 g) and evaluated the sausage's calcium, phosphorus, crude fiber, salt content, pH, CIE color values, texture profile analysis (TPA), emulsion stability, and sensory criteria. It was found that treatment with 3% or 6% NaOH produced better crude protein, ash content, calcium, and CIE color value results than no alkaline treatment. These two NaOH concentrations effectively lowered the salt content and the intensity of the fermented fish smell. However, 3% and 6% NaOH produced similar results. A soaking time of 1 h or 2 h produced better results than no soaking in terms of crude protein, crude fat, ash content, calcium, phosphorus, CIE color values, and the intensity of fermented fish smell. However, 1 h and 2 h produced similar results. It is concluded that 3% NaOH and soaking for 1 h would be the most suitable alkaline treatment to prepare biocalcium from FFBR. Fortifying FES with biocalcium from FFBR increased the calcium and phosphorus contents but slightly reduced TPA. The other FES quality parameters were unaffected by biocalcium fortification.

13.
Nutrients ; 16(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38542820

RESUMO

Brewers' spent grain (BSG) is a fibre and protein-rich by-product of beer-brewing. Fermenting BSG with Rhizopus oligosporus can further increase its content of soluble fibre, protein and certain antioxidants. Since nutrients rich in BSG can improve postprandial glycaemic response, this study assessed the postprandial glucose response (PPGR) and postprandial insulin response (PPIR) controlling effect of consuming 30% wheat flour substituted biscuits with autoclaved BSG (ABSG) or fermented BSG (FBSG) in individuals with metabolic syndrome (MetS). The effect on postprandial lipid panel, breath hydrogen (H2) and methane (CH4) concentration and subjective appetite response was also examined. Fifteen subjects with MetS participated in this crossover randomised controlled trial, and blood was collected at 9 time-points for 4 h after consumption of control biscuits (Control), ABSG and FBSG. A significant interaction effect was observed (Pinteraction = 0.013) for the glucose time-points concentration. At 180 min, the glucose concentration was lowered after the consumption of ABSG (p = 0.010) and FBSG (p = 0.012) compared to the Control. Moreover, the FBSG resulted in a significantly lower glucose incremental area under curve (iAUC) compared to the Control (p = 0.028). Insulin level was also lowered at 180 min after the ABSG (p = 0.010) and FBSG (p = 0.051) consumption compared to the Control. However, no difference was noted for postprandial lipid panel, breath H2 and CH4 concentration and subjective appetite response. In conclusion, the consumption of BSG-incorporated biscuits can attenuate PPGR, and fermented BSG incorporation conferred a further PPGR controlling benefit.


Assuntos
Insulinas , Síndrome Metabólica , Humanos , Farinha , Triticum , Grão Comestível , Glucose , Lipídeos , Estudos Cross-Over
14.
Molecules ; 29(6)2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38542896

RESUMO

The effects of high-pressure processing (HPP) (450 MPa/600 MPa/3 min) on the carotenoid and vitamin E contents of smoothies made from strawberry, orange juice, banana and apple, and the same smoothies enriched with dietary fiber from discarded carrots were compared. The contents and bioaccessibilities of these compounds were also evaluated over the course of 28 days at 4 °C. The application of HPP in the formulations significantly increased the contents of ß-cryptoxanthin, α-carotene and ß-carotene and retained the contents of lutein, zeaxanthin and vitamin E compared to untreated samples. A decreasing trend in the content of each compound was observed with an increase in storage time. The application of HPP initially led to reductions in the bioaccessibility of individual compounds. However, overall, during storage, there was an increase in bioaccessibility. This suggests that HPP influences cell structure, favoring compound release and micelle formation. HPP is a sustainable method that preserves or enhances carotenoid extractability in ready-to-drink fruit beverages. Furthermore, the incorporation of dietary fiber from carrot processing discards supports circular economy practices and enhances the health potential of the product.


Assuntos
Daucus carota , Daucus carota/metabolismo , Vitamina E/análise , Frutas/química , Carotenoides/análise , Fibras na Dieta/análise
15.
Sci Total Environ ; 924: 171436, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38447728

RESUMO

Polychlorinated biphenyls (PCBs) are man-made chemicals that were once widely produced as commercial mixtures for various industrial applications. PCBs were later recognized as environmental pollutants and health hazards, leading to their global phase-out and strict regulations on their production, use, and disposal. Most investigations on PCBs focus on measuring the specific PCBs present in commercial mixtures or marker compounds representing those mixtures. However, there are new sources of PCBs that are gaining more attention. These 'by-product PCBs' are inadvertently produced in certain chemical and product formulations. Our estimates show that U.S. legislation currently permits the generation of more by-product PCBs (~100 million lb. (~45,000 Tonnes) per year) than during peak commercial production of the 1970s (85 million lb. (~39,000 Tonnes) per year). These PCBs are currently going un-detected in most investigations. Therefore, they may be a posing a growing, unmonitored environmental and human health risk. Most people assume PCBs to be legacy pollutants from historically formulated commercial mixtures. However, our research suggests that due to the emergence of by-product PCBs they may need to be reconsidered as an emerging pollutant of concern.


Assuntos
Poluentes Ambientais , Bifenilos Policlorados , Humanos , Bifenilos Policlorados/análise , Poluentes Ambientais/análise
16.
Ultrason Sonochem ; 105: 106856, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554530

RESUMO

The residue remaining after oil extraction from grape seed contain abundant procyanidins. An ultrasonic-assisted enzyme method was performed to achieve a high extraction efficiency of procyanidins when the optimal extraction conditions were 8 U/g of cellulase, ultrasound power of 200 W, ultrasonic temperature of 50 ℃, and ultrasonic reaction time of 40 min. The effects of free procyanidins on both radical scavenging activity and thermal stability at 40, 60, and 80 ℃ of the procyanidins-loaded liposomal systems prepared by the ultrasonic-assisted method were discussed. The presence of procyanidins at concentrations ranging from 0.02 to 0.10 mg/mL was observed to be effective at inhibiting lipid oxidation by 15.15 % to 69.70 % in a linoleic acid model system during reaction for 168 h, as measured using the ferric thiocyanate method. The procyanidins-loaded liposomal systems prepared by the ultrasonic-assisted method were characterized by measuring the mean particle size and encapsulation efficiency. Moreover, the holographic plots showed that the effect-response points of procyanidins combined with α-tocopherol in liposomes were lower than the addition line and 95 % confidence interval limits. At the same time, there were significant differences between the theoretical IC50add value and the experimental IC50mix value. The interaction index (γ) of all combinations was observed to be less than 1. These results indicated that there was a synergistic antioxidant effect between procyanidins combined with α-tocopherol, which will show promising prospects in practical applications. In addition, particle size differentiation and morphology agglomeration were observed at different time points of antioxidant activity determination (0, 48, 96 h).


Assuntos
Antioxidantes , Lipossomos , Proantocianidinas , Proantocianidinas/isolamento & purificação , Proantocianidinas/química , Lipossomos/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Ondas Ultrassônicas , Vitis/química , Extrato de Sementes de Uva/química , Fracionamento Químico/métodos , Tamanho da Partícula , Temperatura , Sementes/química
17.
Bioresour Technol ; 399: 130625, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38518882

RESUMO

Anaerobic digestion (AD) of microalgae is an intriguing approach for bioenergy production. The scaling-up of AD presents a significant challenge due to the systematic efficiency losses related to process instabilities. To gain a comprehensive understanding of AD behavior, this study assessed a modified version of the anaerobic digestion model No1 (ADM1) + Contois kinetics to represent microalgae AD impacted by overloading. To this end, two new inhibition functions were implemented: inhibition by acetate for acidogenesis/acetogenesis and total volatile fatty acids for hydrolysis. This proposed ADM1 modification (including Contois kinetics) simulated AD behavior during the stable, disturbed and recovery periods, showing that the inhibition functions described in the original ADM1 cannot explain the AD performance under one of the most common perturbations at industrial scale (overloading). The findings underscore the importance of refining the inhibitions present in original ADM1 to better capture and predict the complexities of microalgae AD against overloading.


Assuntos
Reatores Biológicos , Microalgas , Anaerobiose , Biomassa , Ácidos Graxos Voláteis , Metano
18.
Int J Biol Macromol ; 265(Pt 1): 130956, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38499118

RESUMO

This study explored the valorisation of silkworm by-product, a major by-product of the silk industry (sericulture), which amounts to 16 million tonnes annually. The focus was on transforming waste into energy resources through pyrolysis under CO2 conditions. In one-stage pyrolysis, the evolution of syngas under N2 was found to be comparable to that under CO2. A notable allocation of carbon to biocrude rather than syngas was observed. The two-stage pyrolysis resulted in increased syngas production. However, achieving a homogeneous reaction between CO2 and the volatiles liberated from silkworm byproduct proved challenging. Indeed, the reaction kinetics governing CO2 reactivity was not fast although the temperature windows of the reaction were aligned in the two-stage pyrolysis. To address this issue, pyrolysis was performed using a Ni-based catalyst to expedite the reaction kinetics. Consequently, syngas formation, particularly CO formation, was significantly enhanced under CO2 conditions compared to that under N2 conditions. The syngas yield under CO2 was 36.42 wt% which was 2-fold higher than that of N2. This suggested the potential of CO2 altering the carbon distribution from biocrude to syngas. This strategy would contribute to the establishment of sustainable production of silk by converting sericulture by-product into energy/chemical resources.


Assuntos
Bombyx , Dióxido de Carbono , Animais , Carbono , Temperatura , Seda
19.
Nat Prod Res ; : 1-6, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538563

RESUMO

Phenolic compounds were extracted from biphasic olive pomace and their biological potential was characterised. Two different extracts were prepared, E1 (40% methanol) and E2 (80% methanol), both subjected to agitation (180 min) and 70 °C. LC-ESI-qTOF-MS was used for individual quantification of the extracted phenolic compounds. The antioxidant activity was determined using different methods, including nitric oxide, DPPH (2,2-diphenyl-1-picrylhydrazyl) and hydroxyl radical. The enzymes α-amylase and α-glucosidase were used to evaluate the antihyperglycemic potential and sulforhodamine B and MTT (tetrazolium salt) for antitumor activity. To evaluate the antimicrobial activity, minimum inhibitory concentration and minimum bactericidal concentration of the extracts, the disc diffusion technique was used. Among the phenolic compounds present, tyrosol was highlighted in both extracts, as well as the anti-hyperglycemic effects, antitumor action and antioxidant activity. The antimicrobial activity found in the extracts was considered moderate to weak.

20.
Sci Total Environ ; 923: 171376, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38432388

RESUMO

Seasonal freezing of waters occurs during winter in cold regions. Bromate ( [Formula: see text] ) is a disinfection by-product generated during water treatment, its interaction with emerging contaminants may be affected by freezing. Nitrite ( [Formula: see text] ) is widely distributed in the environment, whereas its effect on the interaction of emerging contaminants and [Formula: see text] in ice may have been overlooked. Herein carbamazepine (CBZ) was selected as a model emerging contaminant to elucidate the role of reactive nitrogen species (RNS) in contaminant transformation during the reduction of [Formula: see text] by [Formula: see text] in ice. Results indicated that freezing significantly enhanced CBZ degradation by [Formula: see text] . The CBZ degradation by [Formula: see text] and [Formula: see text] in ice was 25.4 %-27.8 % higher than that by [Formula: see text] . Contributions of hydroxyl radical (•OH), bromine radical (•Br), and RNS to CBZ degradation in freezing/dark or sunlight systems were 8.1 % or 15.9 %, 25.4 % or 7.2 %, and 66.5 % or 76.9 %, respectively. Most CBZ was degraded by RNS generated during the reduction of [Formula: see text] by [Formula: see text] in ice, resulting in 16.4 % of transformation products being nitro-containing byproducts. Hybrid toxicity of CBZ/ [Formula: see text] / [Formula: see text] system was reduced effectively after the freezing-sunlight process. This study can provide new insights into the environmental fate of emerging contaminants, [Formula: see text] , and [Formula: see text] in cold regions.

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