RESUMEN
To satisfy the demands of the food industry, innovative flavor enhancers need to be developed urgently to increase the food flavor. In our work, N-lauroyl phenylalanine (LP) was prepared from phenylalanine (l-Phe) and lauric acid (Lau) in water through the use of commercial enzymes (Promatex, Sumizyme FP-G, and Trypsin), and its flavor-presenting properties and mechanism were investigated. The highest LP yields obtained under one-factor optimized conditions were 61.28, 63.43, and 77.58%, respectively. Sensory assessment and an e-tongue test revealed that 1 mg/L LP enhanced the kokumi, saltiness, and umami of the simulated chicken broth solution and attenuated the bitterness of the l-isoleucine solution. The molecular simulation results suggested that the mechanisms of LP enhancement of kokumi and umami were related to hCaSR and hT1R1-hT1R3, and that hydrophobic forces and hydrogen bonds were involved in the binding of LP to taste receptors. The results implied that LP is a potential flavor enhancer for food applications.
Asunto(s)
Aromatizantes , Fenilalanina , Gusto , Fenilalanina/química , Aromatizantes/química , Aromatizantes/metabolismo , Humanos , Ácidos Láuricos/química , Masculino , Animales , Biocatálisis , Adulto , Pollos , Femenino , Adulto JovenRESUMEN
Previous RS5 (type 5 resistant starch) research has significantly broadened starch use and benefited society, yet the effects of the molecular weight of amylose on RS5 remain underexplored. In this study, amyloses with different molecular weights were complexed with caproic acid (C6), lauric acid (C12), and stearic acid (C18) to observe the effects of the molecular weight of amylose on the structure and in vitro digestive properties of RS5. Gel permeation chromatography revealed that the peak average molecular weight (Mp) values of high-amylose cornstarch NF-CGK (CGK), high-amylose cornstarch obtained via cornstarch via autoclave (high temperature and high pressure)-cooling combined pullulanase enzymatic hydrolysis (CTE), and high-amylose cornstarch NF-G370 (HCK) were 21,282, 171,537, and 188,084 before fatty acid complexation, respectively. Additionally, their weight average molecular weight (Mw) values of 32,429, 327,344, and 410,610 and hydrolysis rates of 58.12 %, 86.77 %, and 64.58 %, respectively. The hydrolysis rate of low-Mw amylose (GCK) complexes with fatty acids was lower than that of HCK and CTE starch-lipid complexes. However, HCK and CTE having similar molecular weights, there was no significant difference in the hydrolysis rate of starch-lipid complexes. X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and complexing index analyses confirmed the formation of these complexes. This study proposed the mechanism of RS5 formation and provided guidance for its future development.
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Amilosa , Ácidos Láuricos , Peso Molecular , Amilosa/química , Ácidos Láuricos/química , Hidrólisis , Almidón/química , Almidón/metabolismo , Digestión , Ácidos Esteáricos/química , Lípidos/química , CaprilatosRESUMEN
The effects of complexing conditions on the formation of amylose-lipid-protein complexes and relationships between structure and digestion of amylose-lipid and amylose-lipid-protein complexes were poorly understood. The objective of this study was to investigate the effects of complexing time (0, 0.5, 2, 4 and 6 h) and temperature (60, 70, 80, 90 and 100 °C) on the structure and in vitro amylolysis of amylose-lauric acid (AM-LA) and amylose-lauric acid-ß-lactoglobulin (AM-LA-ßLG) complexes, and to understand the relationships between structure and in vitro digestiblity of these complexes. Longer complexing time and higher complexing temperature promoted the formation of greater amounts of the more stable type II crystallites than type I crystallites in both AM-LA and AM-LA-ßLG complexes, which in turn decreased the rate and extent of the complexes digestion to a greater extent. Correlation analyses between parameters for structure and digestion kinetics showed that both the quantity of AM-LA and AM-LA-ßLG complexes and the quality of their arrangement into V-type crystallites influenced their rate and extent of digestion. This study demonstrates that AM-LA and AM-LA-ßLG complexes can be prepared with designed structural and functional properties tailored for various applications.
Asunto(s)
Amilosa , Lactoglobulinas , Amilosa/química , Lactoglobulinas/química , Lactoglobulinas/metabolismo , Ácidos Láuricos/química , Temperatura , Cinética , Digestión , HidrólisisRESUMEN
Starch, lipids, and proteins are key macronutrients in starchy foods. Their interactions during processing can form starch-lipid-protein ternary complexes, significantly affecting food quality. Ultrasonic treatment, as a common processing method, is expected to regulate the quality of starchy foods by influencing the formation of ternary complexes. This study aimed to understand the effect of ultrasonic pretreatment on the formation of starch-lipid-protein ternary complexes using various types of starches. Wheat starch (WS), maize starch (MS), and potato starch (PS) were gelatinized and treated with ultrasound at various power densities (0-40 W/L) to form complexes with lauric acid (LA) and ß-lactoglobulin (ßLG), respectively. Ultrasound increased the amylose content of gelatinized WS, MS, and PS and shifted their chain length distribution towards the short chains. Results from Fourier transform infrared spectroscopy, laser confocal micro-Raman, X-ray diffraction, and differential scanning calorimetry showed that the largest amount of WS-LA-ßLG complexes was formed at the ultrasonic power density of 10 W/L, and MS-LA-ßLG and PS-LA-ßLG complexes at 20 W/L. Additionally, ultrasound enhanced the content of resistant starch (RS) in the starch-LA-ßLG complexes. The RS content increased from 14.12 % to 18.31 % for WS-LA-ßLG, and from 19.18 % and 20.69 % to 27.60 % and 28.63 % for MS-LA-ßLG and PS-LA-ßLG complexes, respectively. This study presents an approach for facilitating the formation of ternary complexes, contributing to the development of low-GI functional foods.
Asunto(s)
Lactoglobulinas , Ácidos Láuricos , Almidón , Ácidos Láuricos/química , Almidón/química , Lactoglobulinas/química , Ondas Ultrasónicas , DigestiónRESUMEN
This study aimed to explore the effects of various lipids on the structure, cooking quality, and in vitro starch digestibility of extruded buckwheat noodles (EBNs) with and without 20% high-amylose corn starch (HACS). Fourier transform infrared spectroscopy, differential scanning calorimetry, and X-ray diffraction revealed that lauric acid bound more strongly to starch than did stearic acid and oleic acid, and the binding capacity of fatty acids with starch was stronger than that of glycerides. The presence of HACS during extrusion facilitated increased formation of starch-lipid complexes. Evaluations of cooking quality and digestion characteristics showed that EBNs containing 20% HACS and 0.5% glycerol monooleate demonstrated the lowest cooking loss (7.28%), and that with 20% HACS and 0.5% oleic acid displayed the lowest predicted glycemic index (pGI) (63.54) and highest resistant starch (RS) content (51.64%). However, excessive starch-lipid complexes were detrimental to EBNs cooking quality and the resistance of starch to digestive enzymes because of the damage to the continuity of the starch gel network. This study establishes a fundamental basis for the development of EBNs with superior cooking quality and a relatively lower GI.
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Culinaria , Digestión , Fagopyrum , Ácidos Grasos , Almidón , Fagopyrum/química , Ácidos Grasos/química , Almidón/química , Glicéridos/química , Índice Glucémico , Espectroscopía Infrarroja por Transformada de Fourier , Amilosa/química , Difracción de Rayos X , Rastreo Diferencial de Calorimetría , Ácidos Esteáricos/química , Ácido Oléico/química , Ácidos Láuricos/químicaRESUMEN
There is increasing pharmaceutical interest in deep eutectic solvents not only as a green alternative to organic solvents in drug manufacturing, but also as liquid formulation for drug delivery. The present work introduces a hydrophobic deep eutectic solvent (HDES) to the field of lipid-based formulations (LBF). Phase behavior of a mixture with 2:1 M ratio of decanoic- to dodecanoic acid was studied experimentally and described by thermodynamic modelling. Venetoclax was selected as a hydrophobic model drug and studied by atomistic molecular dynamics simulations of the mixtures. As a result, valuable molecular insights were gained into the interaction networks between the different components. Moreover, experimentally the HDES showed greatly enhanced drug solubilization compared to conventional glyceride-based vehicles, but aqueous dispersion behavior was limited. Hence surfactants were studied for their ability to improve aqueous dispersion and addition of Tween 80 resulted in lowest droplet sizes and high in vitro drug release. In conclusion, the combination of HDES with surfactant(s) provides a novel LBF with high pharmaceutical potential. However, the components must be finely balanced to keep the integrity of the solubilizing HDES, while enabling sufficient dispersion and drug release.
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Composición de Medicamentos , Liberación de Fármacos , Interacciones Hidrofóbicas e Hidrofílicas , Lípidos , Simulación de Dinámica Molecular , Solubilidad , Solventes , Tensoactivos , Solventes/química , Tensoactivos/química , Lípidos/química , Composición de Medicamentos/métodos , Polisorbatos/química , Ácidos Láuricos/química , Química Farmacéutica/métodos , Sulfonamidas/química , Sulfonamidas/administración & dosificación , Aceites/químicaRESUMEN
Anti-inflammatory and angiogenesis are two important factors in wound healing. Wound dressings with anti-inflammation and vascularization are essential to address complex interventions, expensive treatments, and uncontrolled release mechanisms. Based on the above considerations, we designed a near-infrared (NIR)-responsive hydrogel dressing, which is composed of mPDA-DFO@LA nanoparticles (mPDA: dopamine hydrochloride nanoparticles, DFO: deferoxamine, LA: lauric acid), valsartan (abbreviated as Va), and dopamine-hyaluronic acid hydrogel. The hydrogel dressing demonstrated injectability, bioadhesive, and photothermal properties. The results indicated the obtained dressing by releasing Va can appropriately regulate macrophage phenotype transformation from M1 to M2, resulting in an anti-inflammatory environment. In addition, DFO encapsulated by LA can be sustainably released into the wound site by NIR irradiation, which further prevents excessive neovascularization. Notably, the results in vivo indicated the mPDA-DFO@LA/Va hydrogel dressing significantly enhanced wound recovery, achieving a healing rate of up to 96% after 11 days of treatment. Therefore, this NIR-responsive hydrogel dressing with anti-inflammation, vascularization, and on-demand programmed drug release will be a promising wound dressing for wound infection.
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Antiinflamatorios , Vendajes , Hidrogeles , Nanocompuestos , Cicatrización de Heridas , Animales , Ratones , Angiogénesis/efectos de los fármacos , Antiinflamatorios/química , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Deferoxamina/química , Deferoxamina/farmacología , Deferoxamina/uso terapéutico , Dopamina/química , Dopamina/farmacología , Hidrogeles/química , Hidrogeles/farmacología , Rayos Infrarrojos , Ácidos Láuricos/química , Ácidos Láuricos/farmacología , Nanocompuestos/química , Nanocompuestos/uso terapéutico , Células RAW 264.7 , Cicatrización de Heridas/efectos de los fármacosRESUMEN
Osteosarcoma (OS) is a highly malignant primary bone neoplasm that is the leading cause of cancerassociated death in young people. GNE477 belongs to the second generation of mTOR inhibitors and possesses promising potential in the treatment of OS but dose tolerance and drug toxicity limit its development and utilization. The present study aimed to prepare a novel H2O2 stimulusresponsive dodecanoic acid (DA)phenylborate esterdextran (DABDEX) polymeric micelle delivery system for GNE477 and evaluate its efficacy. The polymer micelles were characterized by morphology, size and critical micelle concentration. The GNE477 loaded DABDEX (GNE477@DBD) tumortargeting drug delivery system was established and the release of GNE477 was measured. The cellular uptake of GNE477@DBD by three OS cell lines (MG63, U2OS and 143B cells) was analyzed utilizing a fluorescent tracer technique. The hydroxylated DAB was successfully grafted onto dextran at a grafting rate of 3%, suitable for forming amphiphilic micelles. Following exposure to H2O2, the DABDEX micelles ruptured and released the drug rapidly, leading to increased uptake of GNE477@DBD by cells with sustained release of GNE477. The in vitro experiments, including MTT assay, flow cytometry, western blotting and RTqPCR, demonstrated that GNE477@DBD inhibited tumor cell viability, arrested cell cycle in G1 phase, induced apoptosis and blocked the PI3K/Akt/mTOR cascade response. In vivo, through the observation of mice tumor growth and the results of H&E staining, the GNE477@DBD group exhibited more positive therapeutic outcomes than the free drug group with almost no adverse effects on other organs. In conclusion, H2O2responsive DABDEX presents a promising delivery system for hydrophobic antitumor drugs for OS therapy.
Asunto(s)
Dextranos , Peróxido de Hidrógeno , Ácidos Láuricos , Micelas , Osteosarcoma , Animales , Humanos , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/patología , Línea Celular Tumoral , Dextranos/química , Ratones , Ácidos Láuricos/química , Ácidos Láuricos/farmacología , Apoptosis/efectos de los fármacos , Polímeros/química , Polímeros/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/patología , Ratones Desnudos , Antineoplásicos/farmacología , Antineoplásicos/química , Ratones Endogámicos BALB C , Masculino , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
The effects of different electron beam irradiation doses (2, 4, 8 KGy) and various types of fatty acids (lauric acid, stearic acid, and oleic acid) on the formation, structure, physicochemical properties, and digestibility of starch-lipid complex were investigated. The complexing index of the complexes was higher than 85 %, indicating that the three fatty acids could easily form complexes with starch. With the increase of electron beam irradiation dose, the complexing index increased first and then decreased. The highest complexing index was lauric acid (97.12 %), stearic acid (96.80 %), and oleic acid (97.51 %) at 2 KGy radiation dose, respectively. Moreover, the microstructure, crystal structure, thermal stability, rheological properties, and starch solubility were analyzed. In vitro digestibility tests showed that adding fatty acids could reduce the content of hydrolyzed starch, among which the resistant starch content of the starch-oleic acid complex was the highest (54.26 %). The lower dose of electron beam irradiation could decrease the digestibility of starch and increase the content of resistant starch.
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Electrones , Ácidos Grasos , Solubilidad , Almidón , Almidón/química , Ácidos Grasos/química , Ácidos Láuricos/química , Reología , Hidrólisis , Ácido Oléico/química , Lípidos/químicaRESUMEN
Effect of complexation of three medium-chain fatty acids (octanoic, decylic and lauric acid, OA, DA and LA, respectively) on structural characteristics, physicochemical properties and digestion behaviors of cassava starch (CS) was investigated. Current study indicated that LA was more easily to combine with CS (complex index 88.9%), followed by DA (80.9%), which was also consistent with their corresponding complexed lipids content. Following the investigation of morphology, short-range ordered structure, helical structure, crystalline/amorphous region and fractal dimension of the various complexes, all cassava starch-fatty acids complexes (CS-FAs) were characterized with a flaked morphology rather than a round morphology in native starch (control CS). X-ray diffraction demonstrated that all CS-FAs had a V-type crystalline structure, and nuclear magnetic resonance spectroscopy confirmed that the complexes made from different fatty acids displayed similar V6 or V7 type polymorphs. Interestingly, small-angle X-ray scattering analysis revealed that α value became greater following increased carbon chain length of fatty acids, indicating the formation of a more ordered fractal structure in the aggregates. Changes in rheological parameters G' and G'' indicated that starch complexed with fatty acids was more likely to form a gel network, but difference among three CS-FAs complexes was significant, which might be contributed to their corresponding hydrophobicity and hydrophilicity raised from individual fatty acids. Importantly, digestion indicated that CS-LA complexes had the lowest hydrolysis degree, followed by the greatest RS content, indicating the importance of chain length of fatty acids for manipulating the fine structure and functionality of the complexes.
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Digestión , Ácidos Grasos , Ácidos Láuricos , Manihot , Almidón , Difracción de Rayos X , Manihot/química , Almidón/química , Ácidos Láuricos/química , Ácidos Grasos/química , Ácidos Decanoicos/química , Reología , Caprilatos/química , Espectroscopía de Resonancia MagnéticaRESUMEN
This research investigated the effect of lecithin on the complexation of lauric acid with maize starch, potato starch, waxy maize starch, and high amylose maize starch. Rapid visco analysis showed that lecithin altered the setback pattern of potato starch-lauric acid and maize starch-lauric acid mixtures but not waxy maize starch-lauric acid. Further investigation, including differential scanning calorimetry, complex index, and X-ray diffraction, showed that lecithin enhanced the complexation of maize starch, potato starch, and high amylose maize starch with lauric acid. Fourier transform infrared and Raman spectroscopy revealed increasingly ordered structures formed in maize starch-lauric acid-lecithin, potato starch-lauric acid-lecithin, and high amylose maize starch-lauric acid-lecithin systems compared to corresponding binary systems. These highly ordered complexes of maize starch, potato starch, and high amylose maize starch also demonstrated greater resistance to in vitro enzymatic hydrolysis. Waxy maize starch complexation however remained unaffected by lecithin. The results of this study show that lecithin impacts complexation between fatty acids and native starches containing amylose, with the starch source being critical. Lecithin minimally impacted the complexation of low amylose starch and fatty acids.
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Amilosa , Ácidos Láuricos , Lecitinas , Almidón , Zea mays , Ácidos Láuricos/química , Lecitinas/química , Almidón/química , Amilosa/química , Zea mays/química , Solanum tuberosum/química , Hidrólisis , Difracción de Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Rastreo Diferencial de CalorimetríaRESUMEN
In this study, the high amylose corn starch and Canna edulis native starch were compounded with lauric acid and fermented by human fecal inoculation in vitro. Changes in beneficial metabolite profile and microbiota composition were evaluated. The structural properties showed that both NS-12C and HAMS-12C formed V-shaped crystals under the same preparation method, but NS-12C had a higher composite index and resistance content than HAMS-12C. At the end of fermentation, the starch-lauric acid complexes prepared from the two types of starch significantly promoted the formation of short-chain fatty acids and the contents of acetic acid, butyric acid and valeric acid produced by NS-12C were higher than those of HAMS-12C(p>0.05). HAMS-12C and NS-12C both increased the relative abundance of Blautia. Notably, NS-12C also increased the relative abundance of beneficial bacteria Bifidobacterium and Meganomas, while HAMS-12C did not. These results suggested that this effect may be related to starch type and provide a basis for designing and producing functional foods to improve intestinal health in Canna edulis native starch.
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Amilosa , Fermentación , Almidón , Amilosa/química , Almidón/química , Humanos , Heces/microbiología , Heces/química , Microbioma Gastrointestinal , Ácidos Grasos Volátiles/metabolismo , Ácidos Grasos Volátiles/química , Ácidos Láuricos/química , Zea mays/químicaRESUMEN
The present study explored the anticancer activity of a Chitosan-based nanogel incorporating thiocolchicoside and lauric acid (CTL) against oral cancer cell lines (KB-1). Cell viability, AO/EtBr dual staining and Cell cycle analysis were done to evaluate the impact of CTL nanogel on oral cancer cells. Real-time PCR was performed to analyze proapoptotic and antiapoptotic gene expression in CTL-treated KB-1 cells. Further, molecular docking analysis was conducted to explore the interaction of our key ingredient, thiocolchicoside and its binding affinities. The CTL nanogel demonstrated potent anticancer activity by inhibiting oral cancer cell proliferation and inducing cell cycle arrest in cancer cells. Gene expression analysis indicated alterations in Bax and Bcl-2 genes; CTL nanogel treatment increased Bax mRNA expression and inhibited the Bcl-2 mRNA expression, which showed potential mechanisms of the CTL nanogel's anticancer action. It was found that thiocolchicoside can stabilize the protein's function or restore it as a tumour suppressor. The CTL nanogel exhibited excellent cytotoxicity and potent anticancer effects, making it a potential candidate for non-toxic chemotherapy in cancer nanomedicine. Furthermore, the nanogel's ability to modulate proapoptotic gene expression highlights its potential for targeted cancer therapy. This research contributes to the growing interest in Chitosan-based nanogels and their potential applications in cancer treatment.
Asunto(s)
Antineoplásicos , Apoptosis , Quitosano , Colchicina , Colchicina/análogos & derivados , Ácidos Láuricos , Neoplasias de la Boca , Nanogeles , Polietileneimina , Humanos , Quitosano/análogos & derivados , Quitosano/química , Quitosano/farmacología , Ácidos Láuricos/química , Ácidos Láuricos/farmacología , Línea Celular Tumoral , Nanogeles/química , Antineoplásicos/farmacología , Antineoplásicos/química , Colchicina/farmacología , Apoptosis/efectos de los fármacos , Neoplasias de la Boca/tratamiento farmacológico , Neoplasias de la Boca/patología , Simulación del Acoplamiento Molecular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Polietilenglicoles/química , Polietilenglicoles/farmacologíaRESUMEN
Colorectal cancer (CRC) occurs in the colorectum and ranks second in the global incidence of all cancers, accounting for one of the highest mortalities. Although the combination chemotherapy regimen of 5-fluorouracil (5-FU) and platinum(IV) oxaliplatin prodrug (OxPt) is an effective strategy for CRC treatment in clinical practice, chemotherapy resistance caused by tumor-resided Fusobacterium nucleatum (Fn) could result in treatment failure. To enhance the efficacy and improve the biocompatibility of combination chemotherapy, we developed an antibacterial-based nanodrug delivery system for Fn-associated CRC treatment. A tumor microenvironment-activated nanomedicine 5-FU-LA@PPL was constructed by the self-assembly of chemotherapeutic drug derivatives 5-FU-LA and polymeric drug carrier PPL. PPL is prepared by conjugating lauric acid (LA) and OxPt to hyperbranched polyglycidyl ether. In principle, LA is used to selectively combat Fn, inhibit autophagy in CRC cells, restore chemosensitivity of 5-FU as well as OxPt, and consequently enhance the combination chemotherapy effects for Fn-associated drug-resistant colorectal tumor. Both in vitro and in vivo studies exhibited that the tailored nanomedicine possessed efficient antibacterial and anti-tumor activities with improved biocompatibility and reduced non-specific toxicity. Hence, this novel anti-tumor strategy has great potential in the combination chemotherapy of CRC, which suggests a clinically relevant valuable option for bacteria-associated drug-resistant cancers.
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Antineoplásicos , Neoplasias Colorrectales , Fluorouracilo , Ácidos Láuricos , Fluorouracilo/farmacología , Fluorouracilo/química , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Humanos , Ácidos Láuricos/química , Ácidos Láuricos/farmacología , Animales , Ratones , Antineoplásicos/química , Antineoplásicos/farmacología , Fusobacterium nucleatum/efectos de los fármacos , Oxaliplatino/farmacología , Oxaliplatino/química , Sistemas de Liberación de Medicamentos , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Profármacos/química , Profármacos/farmacología , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Antibacterianos/química , Antibacterianos/farmacología , Ratones Endogámicos BALB C , Tamaño de la Partícula , Portadores de Fármacos/químicaRESUMEN
In the present work, lauric acid was taken as a phase change material (PCM), and different nanoparticles (NPs) such as SiO2, TiO2, CuO, and ZnO were taken as the supporting materials. CuO NPs were prepared through the co-precipitation technique; SiO2, TiO2, and ZnO NPs were synthesized via the sol-gel technique. These NPs with different weight fractions were dispersed into molten lauric acid, individually. The variations in thermal properties (phase change temperature and latent heat for solid and liquid) of the prepared composite PCMs due to the dispersion of NPs were observed by DSC analyses. An increase in thermal conductivity of the composite PCMs was observed with the increasing weight fraction of NPs. In order to ascertain the long-term utility, a thermal reliability test was conducted on the composite PCMs with repeated heating and cooling cycles. Also, the specific heats of the pure PCM and the composite PCMs were determined as a function of temperature. Further, the experimental investigation was performed on the pure PCM and the prepared composite PCMs to assess their phase change behavior, and the test results clearly proved that the time required for the complete melting and freezing process of the composite PCMs was less when compared to pure PCM. By considering the above facts, the newly prepared composite PCMs can be recommended as a potential candidate for low-temperature solar heating applications.
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Ácidos Láuricos , Nanoestructuras , Ácidos Láuricos/química , Nanoestructuras/química , Dióxido de Silicio/química , TemperaturaRESUMEN
A model system of gelatinized wheat starch (GWS) and lauric acid (LA) was used to examine the effect of residual short-range molecular order in GWS on the formation of starch-lipid complexes. The extent of residual short-range molecular order, as determined by Raman spectroscopy, decreased with increasing water content or heating duration of gelatinization. The enthalpy changes, crystallinity, short-range molecular order and the in vitro enzymic digestion of GWS-LA complexes increased initially to a maximum and then declined as the short-range molecular order in GWS decreased, showing that there was an optimal amount of residual short-range molecular order in GWS for maximizing GWS-LA complexes formation. Below this optimum amount, the limited disruption of short-range molecular order may constrain the mobility of amylose chains for complexation with LA, whereas with excessive disruption above this amount the amylose chains may be too disorganized or entangled to form complexes with LA. The susceptibility of GWS-LA complexes to enzymatic hydrolysis was influenced by both long- and short-range structural order, and to a lesser extent the amounts of complexes. This study showed clearly the role of short-range molecular order in gelatinized starch in influencing the formation of GWS-LA complexes.
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Amilosa , Almidón , Almidón/química , Amilosa/química , Ácidos Láuricos/química , HidrólisisRESUMEN
Alkali series with different atomic numbers affect the physicochemical properties of aqueous solutions. The micellar properties of aqueous solutions of dodecanoate as surfactants were measured by changing the counterions (C12-Na, C12-K, C12-Rb, and C12-Cs). A plot of Krafft temperature vs. alkali metal atomic number showed a downward convex curve, with its minimum temperature (20°C) in the C12-K system. By contrast, a plot of the critical micelle concentration (CMC) vs. alkali metal atomic number exhibited an upward convex curve with the maximum CMC (25.6 mmol L-1) at C12-K. Furthermore, the minimum surface tension (γ min ) of the solution at the CMC increased with increasing atomic number (C12-Na ≈ C12-K < C12-Rb < C12-Cs). The size of the dodecanoate micelles decreased with increasing atomic number. The ionization degree of the micelles also increased with increasing atomic number of the alkali metal. Small-angle X-ray scattering (SAXS) measurements revealed that alkali dodecanoate micelles formed spherical to ellipsoidal structures. In addition, micelles from the shell region showed large electrostatic repulsion, judging from the shape of the spectrum in the higher Q -1 region. From the measurement results of the solubilization of naphthalene into the micelles, the size of the micelles corresponded to the maximum solubilization quantity of naphthalene.
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Ácidos Láuricos , Micelas , Ácidos Láuricos/química , Metales Alcalinos/química , Propiedades de Superficie , Cationes/química , SolubilidadRESUMEN
The selectivity of adsorption between alkali metal ions (Li+, Na+, K+, Rb+, and Cs+) based on the ionic functional groups of the surfactants was studied using two types of surfactants, dodecanoic acid (DA) and sodium dodecyl sulfate (SDS), in the foam separation system. The results showed that Li+ was preferably removed by foam separation using DA. The removal rates of other alkali metal ions were relatively low, and there were no significant differences among other alkali metal ions (Na+, K+, Rb+, and Cs+). However, Cs+ exhibited the highest removal rate among the mixed alkali metals by foam separation using SDS. From these results, the selectivity of the alkali metal in foam separation was dependent on the type of surfactant.
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Metales Alcalinos , Metales Alcalinos/química , Metales Alcalinos/aislamiento & purificación , Ácidos Láuricos/química , Dodecil Sulfato de Sodio/químicaRESUMEN
One of the current challenges in the post-operative treatment of breast cancer is to develop a local therapeutic vector for preventing recurrence and metastasis. Herein, we develop a core-shell fibrous scaffold comprising phase-change materials and photothermal/chemotherapy agents, as a thermal trigger for programmable-response drug release and synergistic treatment. The scaffold is obtained by in situ growth of a zeolitic imidazolate framework-8 (ZIF-8) shell on the surface of poly(butylene succinate)/lauric acid (PBS/LA) phase-change fibers (PCFs) to create PCF@ZIF-8. After optimizing the core-shell and phase transition behavior, gold nanorods (GNRs) and doxorubicin hydrochloride (DOX) co-loaded PCF@ZIF-8 scaffolds were shown to significantly enhance in vitro and in vivo anticancer efficacy. In a healthy tissue microenvironment at pH 7.4, the ZIF-8 shell ensures the sustained release of DOX. If the tumor recurs, the acidic microenvironment induces the decomposition of the ZIF-8 shell. Under the second near-infrared (NIR-II) laser treatment, GNR-induced thermal not only directly destroys the relapsed tumor cells but also accelerates DOX release by inducing the phase transition of LA. Our study sheds light on a well-designed programmable-response trigger, which provides a promising strategy for post-operative recurrence prevention of cancer.
Asunto(s)
Antibióticos Antineoplásicos/farmacología , Butileno Glicoles/química , Doxorrubicina/farmacología , Fototerapia , Polímeros/química , Animales , Antibióticos Antineoplásicos/química , Materiales Biocompatibles/química , Línea Celular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Ácidos Láuricos/química , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Neoplasias Mamarias Experimentales/patología , Ensayo de Materiales , Ratones , Ratones Endogámicos BALB C , Tamaño de la Partícula , Zeolitas/químicaRESUMEN
In this work, low molecular weight (17 kDa) hyaluronan was modified by dodecanoyl substituents. The activation of dodecanoic acid was mediated by benzoyl chloride towards the preparation of a mixed anhydride, which reacts in a second step with HA in water mixed with an organic solvent. The effect of the cosolvent was studied and showed an even distribution of substituents and higher reaction rate in water: 1,4-dioxane compared to water:tert-butanol where substituents occupy adjacent positions. The chemical characterization of the prepared derivatives was elucidated by NMR, FTIR spectroscopy, thermal analyses, and gas chromatography, while the distribution of substituents was evaluated by enzymatic degradation. Molecular-dynamics simulations reveal opposite solvent separations around HA and dodecanoyl chains, that is stronger in water:tert-butanol solution. The resulting incompatibility of solvation-shells of the two entities repels the reaction intermediates from the HA chain and drives them towards the already bound substituents, explaining the observed differences in the distribution evenness. Thus, the influence of the solvent on the reaction selectivity is observed by shielding reactive sites around HA. Therefore, a control of the distribution of the substituents was obtained by defining the concentration of HA and used cosolvent.