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1.
Mol Pharm ; 19(2): 532-546, 2022 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-34958588

RESUMEN

The present study systematically investigates the effect of annealing conditions and the Kolliphor P 407 content on the physicochemical and structural properties of Compritol (glyceryl behenate) and ternary systems prepared via melt cooling (Kolliphor P 407, Compritol, and a hydrophilic API) representing solid-lipid formulations. The physical properties of Compritol and the ternary systems with varying ratios of Compritol and Kolliphor P 407 were characterized using differential scanning calorimetry (DSC), small- and wide-angle X-ray scattering (SWAXS) and infrared (IR) spectroscopy, and hot-stage microscopy (HSM), before and after annealing. The change in the chemical profiles of different Compritol components as a function of annealing was evaluated using 1H NMR spectroscopy. While no change in the polymorphic form of API and Kolliphor P 407 occurred during annealing, a systematic conversion of the α- to ß-form was observed in the case of Compritol. Furthermore, the polymorphic transformation of Compritol was found to be dependent on the Kolliphor P 407 content. As per the Flory-Huggins mixing theory, higher miscibility was observed in the case of monobehenin-Kolliphor P 407, monobehenin-dibehenin, and dibehenin-tribehenin binary mixtures. The miscibility of Kolliphor P 407 with monobehenin and 1,2-dibehenin was confirmed by 1H NMR analysis. The observed higher miscibility of Kolliphor P 407 with monobehenin and 1,2-dibehenin is proposed as the trigger for the physical separation from the 1,3-diglyceride and triglycerides during melt solidification of the formulations. The phase separation is postulated as the mechanism underlying the formation of a stable ß-polymorphic form (a native form of 1,3-diglyceride) of Compritol upon annealing. This finding is expected to have an important implication for developing stable solid-lipid-surfactant-based drug formulations.


Asunto(s)
Excipientes , Tensoactivos , Rastreo Diferencial de Calorimetría , Composición de Medicamentos , Excipientes/química , Transición de Fase , Solubilidad , Tensoactivos/química
2.
PLoS One ; 17(5): e0268835, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35594310

RESUMEN

Promyelocytic leukemia (PML) proteins are involved in the pathogenesis of acute promyelocytic leukemia (APL). Trivalent arsenic (As3+) is known to cure APL by binding to cysteine residues of PML and enhance the degradation of PML-retinoic acid receptor α (RARα), a t(15;17) gene translocation product in APL cells, and restore PML-nuclear bodies (NBs). The size, number, and shape of PML-NBs vary among cell types and during cell division. However, topological changes of PML-NBs in As3+-exposed cells have not been well-documented. We report that As3+-induced solubility shift underlies rapid SUMOylation of PML and late agglomeration of PML-NBs. Most PML-NBs were toroidal and granular dot-like in GFPPML-transduced CHO-K1 and HEK293 cells, respectively. Exposure to As3+ and antimony (Sb3+) greatly reduced the solubility of PML and enhanced SUMOylation within 2 h in the absence of changes in the number and size of PML-NBs. However, the prolonged exposure to As3+ and Sb3+ resulted in agglomeration of PML-NBs. Exposure to bismuth (Bi3+), another Group 15 element, did not induce any of these changes. ML792, a SUMO activation inhibitor, reduced the number of PML-NBs and increased the size of the NBs, but had little effect on the As3+-induced solubility change of PML. These results warrant the importance of As3+- or Sb3+-induced solubility shift of PML for the regulation intranuclear dynamics of PML-NBs.


Asunto(s)
Arsénico , Leucemia Promielocítica Aguda , Arsénico/metabolismo , Arsénico/farmacología , Núcleo Celular/metabolismo , Células HEK293 , Humanos , Leucemia Promielocítica Aguda/metabolismo , Proteína de la Leucemia Promielocítica/genética , Proteína de la Leucemia Promielocítica/metabolismo , Solubilidad , Factores de Transcripción/metabolismo
3.
Proc Natl Acad Sci U S A ; 119(21): e2114277119, 2022 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-35594395

RESUMEN

SignificanceThis contribution offers a proof of concept to make it possible to target a specific (co)crystal at molecular scale within a continuous process. The paper, while addressing a very important issue in public health, i.e., high-efficiency medicine production, also emphasizes the significance of computational material science and data science in generating proper understanding of a process and its optimal operating conditions.


Asunto(s)
Solubilidad , Cristalización , Cristalografía , Preparaciones Farmacéuticas
4.
Sci Rep ; 12(1): 8510, 2022 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35595847

RESUMEN

Due to the pivotal role of angiogenesis in bone regeneration, the angiogenic properties of biomaterials are of high importance since they directly correlate with the biomaterials' osteogenic potential via 'angiogenic-osteogenic coupling' mechanisms. The impact of bioactive glasses (BGs) on vascularization can be tailored by incorporation of biologically active ions such as boron (B). Based on the ICIE16-BG composition (in mol%: 49.5 SiO2, 36.3 CaO, 6.6 Na2O, 1.1 P2O5, 6.6 K2O), three B-doped BGs have been developed (compositions in mol%: 46.5/45.5/41.5 SiO2, 36.3 CaO, 6.6 Na2O, 1.1 P2O5, 6.6 K2O, 3/4/8 B2O3). The influence of B-doping on the viability, cellular osteogenic differentiation and expression of osteogenic and angiogenic marker genes of bone marrow-derived mesenchymal stromal cells (BMSCs) was analyzed by cultivating BMSCs in presence of the BGs' ionic dissolution products (IDPs). Furthermore, the influence of the IDPs on angiogenesis was evaluated in ovo using a chorioallantoic membrane (CAM) assay. The influence of B-doped BGs on BMSC viability was dose-dependent, with higher B concentrations showing limited negative effects. B-doping led to a slight stimulation of osteogenesis and angiogenesis in vitro. In contrast to that, B-doping significantly enhanced vascularization in ovo, especially in higher concentrations. Differences between the results of the in vitro and in ovo part of this study might be explained via the different importance of vascularization in both settings. The implementation of new experimental models that cover the 'angiogenic-osteogenic coupling' mechanisms is highly relevant, for instance via extending the application of the CAM assay from solely angiogenic to angiogenic and osteogenic purposes.


Asunto(s)
Boro , Osteogénesis , Materiales Biocompatibles/farmacología , Boro/farmacología , Supervivencia Celular , Vidrio , Iones , Silicatos/farmacología , Dióxido de Silicio , Solubilidad
5.
AAPS PharmSciTech ; 23(5): 151, 2022 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35596043

RESUMEN

The importance of lipid-based formulations in addressing solubility and ultimately the bioavailability issues of the emerging drug entities is undeniable. Yet, there is scarcity of literature on lipid excipient chemistry and performance, notably in relation to oxidative stability. While not all lipid excipients are prone to oxidation, those with sensitive moieties offer drug delivery solutions that outweigh the manageable oxidative challenges they may present. For example, caprylocaproyl polyoxylglycerides help solubilize and deliver cancer drug to patients, lauroyl polyoxylglycerides enhance the delivery of cholesterol lowering drug, and sesame/soybean oils are critical part of parenteral nutrition. Ironically, excipients with far greater oxidative propensity are omnipresent in pharmaceutical products, a testament to the manageability of oxidative challenges in drug development. Successful formulation development requires awareness of what, where, and how formulation stability may be impacted, and accordingly taking appropriate steps to circumvent or meet the challenges ahead. Aiming to fill the information gap from a drug delivery scientist perspective, this review discusses oxidation pathways, prooxidants, antioxidants, and their complex interplay, which can paradoxically take opposite directions depending on the drug delivery system.


Asunto(s)
Excipientes , Lípidos , Estabilidad de Medicamentos , Excipientes/metabolismo , Humanos , Estrés Oxidativo , Preparaciones Farmacéuticas , Solubilidad
6.
Sci Rep ; 12(1): 7100, 2022 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-35501338

RESUMEN

Regulatory testing of hydraulic cements used in dentistry and standard test methods for root-end filling materials do not exist. The aim of this study was to identify a simple, reproducible method for testing the solubility of materials that set with water (hydraulic) used as root-end filling materials in dentistry. Commercial and prototype hydraulic cements were characterized by scanning electron microscopy and X-ray diffraction analyses and their solubilities were determined using ISO 6876; 2012 standard, a modified ISO 6876 method with media alternative to water and a new method measuring the percentage mass loss and volume change of materials (micro-CT method) from a single surface exposed to three solutions. The solubility testing was performed by three operators to enable an intra-laboratory comparison. The solubility data obtained from the two commercial and two prototype materials varied depending on the method used, with the ISO 6876 method identifying differences in solubility of the materials (p < 0.05) but when modified with alternative solutions, no differences were found (p > 0.05). The changes in solution thus effected the solubility of the tested materials. Inter-operator differences were observed with the weight changes determined from the new method indicating this method was not robust. The weight and volume assessments using the new method were not solution-dependent. The advantage of the proposed method compared with the ISO standard is its simplicity, enabling a number of tests to be performed on the same set of samples that also more closely mimics the clinical environment.


Asunto(s)
Materiales de Obturación del Conducto Radicular , Compuestos de Calcio , Silicatos , Solubilidad , Agua
7.
Eur Rev Med Pharmacol Sci ; 26(8): 3010-3024, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35503601

RESUMEN

OBJECTIVE: The aim of the study was to improve the bioavailability of Cinacalcet hydrochloride (CLC) and enhance its efficacy by the nanoemulsion drug delivery system. MATERIALS AND METHODS: First, cinacalcet hydrochloride-nanoemulsion (CLC-NE) was prepared and optimized through the pseudo ternary phase diagram and central composite design response surface methodology (CCD). The release of CLC-NE in vitro was investigated with four different dissolution media, and the bioavailability of CLC-NE in vivo was studied through beagle dogs. Finally, the pharmacodynamics of CLC-NE was evaluated by the rat model of uremia. RESULTS: Oleic acid, op-10, and PEG-200 were selected as oil phase, emulsifier, and co-emulsifier, respectively. The optimum ratio of oleic acid, op-10, PEG-200, and water was 9.87%, 38.33%, 12.78%, and 39.02%. CLC-NE has similar dissolution rates in different pH media, and the relative bioavailability of CLC-NE was 166.5%. The uremia model showed that CLC-NE could enhance renal function and reduce the excessive phosphorus (P), serum creatinine (Scr), and urea nitrogen (Urea) of model rats, as well as the inhibited increase of fibroblast growth factor-23 (FGF23) and parathyroid hormone (PTH). CONCLUSIONS: The solubility, bioavailability, and pharmacodynamics of CLC can be significantly improved through the nanoemulsion drug delivery system.


Asunto(s)
Nanopartículas , Uremia , Animales , Disponibilidad Biológica , Cinacalcet/farmacología , Perros , Sistemas de Liberación de Medicamentos/métodos , Emulsiones/química , Femenino , Humanos , Masculino , Nanopartículas/química , Ácido Oléico , Tamaño de la Partícula , Ratas , Solubilidad , Urea
8.
AAPS PharmSciTech ; 23(5): 133, 2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35534652

RESUMEN

Sediment delivery model (SeDeM) system is innovative tool to correlate micromeritic properties of powders with compressibility. It involves computation of indices which facilitate direct compressibility of solids and enable corrective measures through particle engineering. Study had multiple objectives, viz, (i) to enhance solubility of BCS class II, nevirapine using solid dispersions; (ii) SeDeM analyses of excipients and solid dispersions to analyze direct compressibility; and (iii) prepare orodispersible tablets (ODT). Solid dispersions were prepared by solvent evaporation. Superdisintegrants and solid dispersions were analyzed for primary indices of dimension, compressibility, flowability, stability, and disgregability derived from micromeritic properties. Radar diagrams were constructed to provide visual clues to deficient properties for direct compressibility. ODTs were prepared using excipients which passed criteria for direct compressibility and evaluated for tablet properties. Solid dispersions with Eudragit S100 revealed 6 to 10 fold increase in solubility in various dissolution media including biorelevant media in comparison with plain drug. Solubility was found to be pH dependent. SeDeM analyses facilitated identification of superdisintegrants and excipients with unfavorable compressibility. Radar diagrams provided a clear pictorial evidence of lacunae in powder properties. Based on SeDeM results, tablets were formulated by direct compression using crosspovidone, croscarmellose sodium, and mannitol. All batches showed 40% release in first minute in simulated salivary fluid.


Asunto(s)
Excipientes , Sistemas Especialistas , Composición de Medicamentos/métodos , Excipientes/química , Polvos/química , Solubilidad , Comprimidos/química
9.
AAPS PharmSciTech ; 23(5): 134, 2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35534702

RESUMEN

Nature has been used as therapeutic resources in the treatment of diseases for many years. However, some natural compounds have poor water solubility. Therefore, physicochemical strategies and technologies are necessary for development of systems for carrying these substances. The self-emulsifying drug delivery systems (SEDDS) have been used as carriers of hydrophobic compounds in order to increase the solubility and absorption, improving their bioavailability. SEDDS are constituted with a mixture of oils and surfactants which, when come into contact with an aqueous medium under mild agitation, can form emulsions. In the last years, a wide variety of self-emulsifying formulations containing bioactive compounds from natural origin has been developed. This review provides a comprehensive overview of the main excipients and natural bioactive compounds composing SEDDS. In addition, applications, new technologies and innovation are reviewed as well. Examples of self-emulsifying formulations administered in different sites are also considered for a better understanding of the use of this strategy to modify the delivery of compounds from natural origin.


Asunto(s)
Sistemas de Liberación de Medicamentos , Excipientes , Administración Oral , Disponibilidad Biológica , Emulsiones/química , Excipientes/química , Solubilidad
10.
AAPS PharmSciTech ; 23(5): 138, 2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35534746

RESUMEN

Rifampicin (RFP) solutions, intended to reduce incidence of prosthetic graft infection, were prepared as three-dimensional ground mixtures (3DGMs) using ß-cyclodextrin (ßCD) and γ-cyclodextrin (γCD) and characterized for their spectroscopic properties and solubility. Phase solubility diagrams revealed that 3DGMs (RFP/ßCD and RFP/γCD) produced a complex at 1:1 molar ratio. Pulsed field gradient nuclear magnetic resonance experiments indicated that the diffusion coefficients for RFP/ßCD and RFP/γCD were similar to the respective diffusion coefficients for ßCD and γCD. Rotating-frame Overhauser effect spectroscopy NMR spectra revealed the existence of a new exchanger peak for RFP/γCD, suggesting an intermolecular interaction different from that of RFP/ßCD. Differential scanning calorimetry confirmed the presence of endothermic peak at 191 °C indicating the manifestation of RFP in the inclusion complex. Interestingly, molecular interactions from the complexes, RFP/ßCD and RFP/γCD, revealed different patterns of inclusion in the 3DGMs. In RFP/ßCD, nuclear Overhauser effect spectroscopy NMR spectra indicated cross peaks for the protons of the methyl group of RFP and the protons (H-5 and H-6) in the ßCD cavity. The methyl group of RFP interacted with the narrow rim of ßCD. With RFP/γCD, cross peaks were due to the protons of the methyl group of RFP and the protons of the cavity of γCD suggesting multiple inclusion patterns. The observed multiple cross peaks affirm the inclusion of RFP into the CD cavity which enhanced its solubility by 1.6-2.0-fold when prepared as 3DGMs as RFP/ßCD and RFP/γCD, respectively.


Asunto(s)
beta-Ciclodextrinas , gamma-Ciclodextrinas , Espectroscopía de Resonancia Magnética , Protones , Rifampin , Solubilidad , beta-Ciclodextrinas/química , gamma-Ciclodextrinas/química
11.
Drug Deliv ; 29(1): 1398-1408, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35532137

RESUMEN

Triptolide (TP), a compound isolated from a Chinese medicinal herb, possesses potent anti-tumor, immunosuppressive, and anti-inflammatory properties, but was clinically limited due to its poor solubility, bioavailability, and toxicity. Considering the environment-friendly, low-cost mechanochemical techniques and potential dissolution enhancement ability of Na2GA, an amorphous solid dispersion (Na2GA&TP-BM) consisting of TP and Na2GA were well-prepared to address these issues. The performance of Na2GA&TP-BM was improved through ball milling, such as from crystalline state to an amorphous solid dispersion, suitable nano micelle size and surface potential, and increased solubility. This change had a significant improvement of pharmacokinetic behavior in mice and could be able to extend the blood circulation time of the antitumor drug. Moreover, in vitro and in vivo anti-tumor study showed that Na2GA&TP-BM displayed more potent cytotoxicity to tumor cells. The work illustrated an environment-friendly and safe preparation of the TP formulation, which was promising to enhance the oral bioavailability and antitumor ability of TP, might be considered for efficient anticancer therapy.


Asunto(s)
Diterpenos , Fenantrenos , Administración Oral , Animales , Disponibilidad Biológica , Diterpenos/farmacología , Compuestos Epoxi , Ratones , Micelas , Fenantrenos/farmacología , Solubilidad
12.
AAPS PharmSciTech ; 23(5): 142, 2022 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-35538251

RESUMEN

Many active pharmaceutical ingredients (API) are poorly soluble in water and their low oral bioavailability is a major hindrance to their potential use. Megestrol acetate (MGA) is insoluble in water and its oral absorption is limited and considerably affected by food. Nanoemulsions (NEs) can be used as effective oral drug delivery systems where the hydrophobic API is loaded into the oil phase. In this study, MGA-loaded NEs were prepared based on the spontaneous emulsification technique. The effects of different excipients such as ethanol, Tween 80, Lipoid E80, and medium-chain triglyceride (MCT) on the NEs characterization were investigated. The experimental results indicated that optimum MGA-loaded NEs (F20) were nanometer-sized droplets (166.9 ± 3.0 nm) with negative zeta potential (-12.2 ± 1.1 mV). The effect of polyvinylpyrrolidone (PVP) on characteristic properties of F20 was also evaluated. On the selected NEs, in vitro dissolution tests and stability studies in various mediums and storage conditions were performed. The encapsulation efficiency of NEs were > 99%. The overall droplet size of F20 and PVP-2 (PVP-coated NEs) remained relatively stable as the pH changed from 1.2 to 6.8. It was determined that F20 and PVP-2 remained stable at 4°C until 12 weeks and had higher cytotoxicity on MCF-7 cells. To conclude, droplet size, surface charge, and stability are important properties for NEs to have sufficient effectiveness. In this study, alternative oral NEs of low-solubility drug MGA were developed considering the above features.


Asunto(s)
Acetato de Megestrol , Polisorbatos , Emulsiones/química , Humanos , Solubilidad , Agua/química
13.
AAPS PharmSciTech ; 23(5): 141, 2022 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-35538376

RESUMEN

Due to poor solubility and stability in acid conditions, the gastrointestinal administration of stiripentol (STP) is still a significant challenge. This study aimed to explore the applicability of effervescent tablets compressed from STP-loaded enteric solid dispersions to improve the solubility and stability of the insoluble and acid-labile drug. STP-loaded solid dispersions (STP-SDs) and the effervescent tablets (STP-SD-ETs) were prepared using solvent evaporation and dry granulation technology, respectively, and their formulations were optimized. Then, STP-SDs were characterized regarding solid state, in vitro release, stability, etc. Results showed that enteric amorphous STP-SDs were successfully prepared and significantly improved the solubility and stability of STP. Moreover, compared with STP suspensions, the bioavailability of STP-SD-ETs was as high as 138.71%. Concomitantly, STP-SD-ETs significantly increased the intestinal absorption rate of STP. Overall, the oral preparation encompassing enteric solid dispersion combined with effervescent tablet technology possesses excellent performance in enhancing dissolution, anti-acid hydrolysis stability, and absorption of STP. Our work provides a promising method to improve the delivery of drugs with poor solubility and acid-labile stability.


Asunto(s)
Dioxolanos , Disponibilidad Biológica , Solubilidad , Comprimidos
14.
AAPS J ; 24(3): 60, 2022 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-35501614

RESUMEN

Traditionally, excipients have been considered in drug development from the perspective of their influence on drug solubility, manufacturability, and ability to control in vitro and in vivo drug release. These effects have been largely evaluated through studies involving in vitro dissolution methods. However, there is a growing awareness that what had previously been considered biologically inert excipients can exert numerous in vivo effects. This includes the potential to change gastrointestinal (GI) transit time, enterocyte passive transcellular or paracellular permeability, active transport activity, or presystemic drug metabolism. In this critical overview of the biological effects of excipients (Part I), we provide a summary of select published studies that explore these various in vivo factors. We also include a table that points readers to published reviews that list a range of excipients known to have biological activity. A subsequent discussion on in vitro, in vivo, and in silico methods that can be used to explore these excipient effects is provided in a separate (Part 2) continuation of this critical overview.


Asunto(s)
Excipientes , Absorción Intestinal , Permeabilidad , Solubilidad
15.
Food Chem ; 389: 132664, 2022 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-35523074

RESUMEN

Nitrogen is an essential element for the yield and quality of grain. In this study, the structural and physicochemical properties of two common buckwheat varieties under four nitrogen levels (0, 90, 180, 270 kg N ha-1) at one location in two years were investigated. With increasing nitrogen level, the contents of moisture and amylose decreased but the contents of ash and crude protein increased. Excessive nitrogen application significantly increased the granule size, but reduced the light transmittance, water solubility, swelling power, absorption of water and oil. All the samples showed a typical A - type pattern, while high relative crystallinity and low order degree were observed under high nitrogen level. The samples under high nitrogen level had lower textural properties, pasting properties and rheological properties but higher pasting temperature and gelatinization enthalpy. These results indicated that nitrogen fertilizer significantly affected the structural and physicochemical properties of common buckwheat starch.


Asunto(s)
Fagopyrum , Almidón , Amilosa/química , Fagopyrum/química , Fertilizantes , Nitrógeno/metabolismo , Solubilidad , Almidón/química , Viscosidad , Agua/química
16.
AAPS PharmSciTech ; 23(5): 140, 2022 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-35538248

RESUMEN

Aqueous colloidal dispersions of water-insoluble polymers (APDs) avoid hassles associated with the use of organic solvents and offer processing advantages related to their low viscosity and short processing times. Therefore, they became the main vehicle for pharmaceutical coating of tablets and multiparticulates, a process commonly employed using pan and fluidized-bed machinery. Another interesting although less common processing approach is co-spray drying APDs with drugs in aqueous systems. It enables the manufacture of capsule- and matrix-type microspheres with controllable size and improved processing characteristics in a single step. These microspheres can be further formulated into different dosage forms. This systematic review is based on published research articles and aims to highlight the applicability and opportunities of co-spray drying drugs with APDs in drug delivery.


Asunto(s)
Polímeros , Secado por Pulverización , Composición de Medicamentos , Excipientes , Solubilidad , Comprimidos , Agua
17.
Int J Mol Sci ; 23(7)2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35408938

RESUMEN

Oxidative dissolution of stibnite (Sb2S3), one of the most prevalent geochemical processes for antimony (Sb) release, can be promoted by Sb-oxidizing microbes, which were studied under alkaline and neutral conditions but rarely under acidic conditions. This work is dedicated to unraveling the enhancement mechanism of stibnite dissolution by typical acidophile Acidithiobacillus ferrooxidans under extremely acidic conditions. The results of solution behavior showed that the dissolution of Sb2S3 was significantly enhanced by A. ferrooxidans, with lower pH and higher redox potential values and higher [Sb(III)] and [Sb(V)] than the sterile control. The surface morphology results showed that the cells adsorbed onto the mineral surface and formed biofilms. Much more filamentous secondary minerals were formed for the case with A. ferrooxidans. Further mineral phase compositions and Sb/S speciation transformation analyses showed that more secondary products Sb2O3/SbO2-, Sb2O5/SbO3-, SO42-, as well as intermediates, such as S0, S2O32- were formed for the biotic case, indicating that the dissolution of Sb2S3 and the Sb/S speciation transformation was promoted by A. ferrooxidans. These results were further clarified by the comparative transcriptome analysis. This work demonstrated that through the interaction with Sb2S3, A. ferrooxidans promotes S/Sb oxidation, so as to enhance S/Sb transformation and thus the dissolution of Sb2S3.


Asunto(s)
Acidithiobacillus , Antimonio/química , Minerales/química , Oxidación-Reducción , Solubilidad
18.
Ultrason Sonochem ; 85: 105969, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35364471

RESUMEN

The denaturation and lower solubility of commercial potato proteins generally limited their industrial application. Effects of high-intensity ultrasound (HIU) (200, 400, and 600 W) and treatment time (10, 20, and 30 min) on the physicochemical and functional properties of insoluble potato protein isolates (ISPP) were investigated. The results revealed that HIU treatment induced the unfolding and breakdown of macromolecular aggregates of ISPP, resulting in the exposure of hydrophobic and R-SH groups, and reduction of the particle size. These active groups contributed to the formation of a dense and uniform gel network of ISPP gel and insoluble potato proteins/egg white protein (ISPP/EWP) hybrid gel. Furthermore, the increase of solubility and surface hydrophobicity and the decrease of particle size improved the emulsifying property of ISPP. However, excessive HIU treatment reduced the emulsification and gelling properties of the ISPP. Meanwhile, HIU treatment changes the secondary structure of ISPP. It could be speculated that the formation of a stable secondary structure of ISPP initiated by cavitation and shearing effect might play a dominant role on gel strengthens and firmness. Meanwhile, the decrease in relative content of ß-turn had a positive effect on the formation of small particle to improve emulsifying property of ISPP.


Asunto(s)
Solanum tuberosum , Geles , Interacciones Hidrofóbicas e Hidrofílicas , Solubilidad , Ondas Ultrasónicas
19.
Ultrason Sonochem ; 85: 105993, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35367738

RESUMEN

High intensity ultrasound (HIU) is an efficient and green technology that has recently received enormous research attention for modification of food proteins. However, there are still several knowledge gaps in the possible mechanisms, synergistic effects of HIU with other strategies and improvement of HIU equipment that contribute to its application in the food industry. This review focuses on the recent research progress on the effects and potential mechanisms of HIU on the structure (including secondary and tertiary structure) and functionality (including solubility, emulsibility, foamability, and gelability) of proteins. Furthermore, the combination methods and innovations of HIU equipment for proteins modification in recent years are also detailed. Meanwhile, the possible future trends of food proteins modification by HIU are also considered and proposed.


Asunto(s)
Solubilidad
20.
Yakugaku Zasshi ; 142(4): 365-379, 2022.
Artículo en Japonés | MEDLINE | ID: mdl-35370193

RESUMEN

Sufficient aqueous solubility is a key requirement for small molecular drug candidates, and improvement of the aqueous solubility of bioactive compounds is often a major issue for medicinal chemists. Decreasing the partition coefficient (Log P) by the introduction of a hydrophilic group is the conventional approach for improving the aqueous solubility of drug candidates, but is not always effective. On the other hand, the solubility of a solid solute in water is also dependent on the crystal packing of the solute suggesting the existence of another principle of solvation. We have developed alternative strategies to improve solubility by means of chemical modification to weaken intermolecular interaction in the solid state, thereby lowering the melting point and increasing the solubility. In this review, we summarize the strategies for improving solubility, that is, modification of molecules in ways that would disrupt molecular planarity by increasing the dihedral angle, that would bend the molecular structure, that would disrupt molecular symmetry, or that introduce a non-flat substituent at the meta position of a benzene substructure. We showed that these strategies can increase the aqueous solubility of molecules even if their hydrophobicity is concomitantly increased. Furthermore, we found that disruption of intermolecular interaction resulted in better aqueous solubility than a decrease of hydrophobicity in some cases.


Asunto(s)
Agua , Interacciones Hidrofóbicas e Hidrofílicas , Estructura Molecular , Solubilidad , Agua/química
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