A simple blending with α-glycosylated naringin produces enhanced solubility and absorption of pranlukast hemihydrate

Solubilization mechanism of α-glycosylated naringin based on self-assembled nanostructures and its application to skin formulation

We previously reported that α-glycosylated naringin (naringin-G), synthesized by enzyme-catalyzed transglycosylation, can enhance the solubility of poorly water-soluble compounds without surface-active property. However, the solubilization mechanism has not been fully elucidated. In this study, the solubilization mechanism of naringin-G was investigated using nuclear magnetic resonance (NMR) spectroscopy, and its application in skin formulations was further investigated. 1H NMR and dynamic light scattering measurements at various concentrations confirmed the self-assembled nanostructures of naringin-G above a critical aggregation concentration of approximately 2.2 mg/mL. Two-dimensional 1H-1H nuclear Overhauser effect spectroscopy and solubility tests revealed that flavone with poor water solubility, could be solubilized in its self-assembled structure with a stoichiometric relationship with naringin-G. When naringin-G was included in the skin formulation, the permeated amount and permeability coefficient (Papp) of flavones improved up to four times with increasing amounts of naringin-G. However, flavone solubilization by adding an excessive amount of naringin-G resulted in a decreased permeated amount and Papp of flavones, indicating the interplay between the apparent solubility and skin permeability of flavones. Naringin-G, which forms a nanoaggregate structure without exhibiting surface-active properties, has the potential to enhance the solubility and skin permeation of poorly water-soluble compounds.

Naturally Occurring Isorhamnetin Glycosides as Potential Agents Against Influenza Viruses: Antiviral and Molecular Docking Studies

Influenza remains one of the most widespread infections, causing an annual illness in adults and children. Therefore, the search for new antiviral drugs is one of the priorities of practical health care. Eight isorhamnetin glycosides were purified from Persicaria species, characterized by nuclear magnetic resonance spectroscopy and mass spectrometry and then evaluated as potential agents against influenza virus. A comprehensive in vitro and in vivo assessment of the compounds revealed that compound 5 displayed the most potent inhibitory activity with an EC50 value of 1.2-1.3 μM, better than standard drugs (isorhamnetin 28.0-56.0 μM and oseltamivir 1.3-9.1 μM). Molecular docking results also revealed that compound 5 has the lowest binding energy (-10.7 kcal/mol) among the tested compounds and isorhamnetin (-8.1 kcal/mol). The ability of the isorhamnetin glycosides to suppress the reproduction of the influenza virus was studied on a model of a cell culture and chicken embryos. The ability of active compounds to influence the structure of the virion, as well as the activity of hemagglutinin and neuraminidase, has been demonstrated. Compound 1, 5, and 6 demonstrated the most effective inhibition of virus replication for all tested viruses. Molecular dynamics simulation techniques were run for 100 ns for compound 5 with two protein receptors Hem (1RUY) and Neu (3BEQ). These results revealed that the Hem-complex system acquired a relatively more stable conformation and even better descriptors than the other Neu-complex studied systems, suggesting that it can be an effective inhibiting drug toward hemagglutinin than neuraminidase inhibition. Based on the reported results, compound 5 can be a good candidate to be evaluated for effectiveness in preclinical testing.

Biological Activities and Solubilization Methodologies of Naringin

Naringin (NG), a natural flavanone glycoside, possesses a multitude of pharmacological properties, encompassing anti-inflammatory, sedative, antioxidant, anticancer, anti-osteoporosis, and lipid-lowering functions, and serves as a facilitator for the absorption of other drugs. Despite these powerful qualities, NG's limited solubility and bioavailability primarily undermine its therapeutic potential. Consequently, innovative solubilization methodologies have received considerable attention, propelling a surge of scholarly investigation in this arena. Among the most promising solutions is the enhancement of NG's solubility and physiological activity without compromising its inherent active structure, therefore enabling the formulation of non-toxic and benign human body preparations. This article delivers a comprehensive overview of NG and its physiological activities, particularly emphasizing the impacts of structural modification, solid dispersions (SDs), inclusion compound, polymeric micelle, liposomes, and nanoparticles on NG solubilization. By synthesizing current research, this research elucidates the bioavailability of NG, broadens its clinical applicability, and paves the way for further exploration and expansion of its application spectrum.

Solubilisation and Enhanced Oral Absorption of Curcumin Using a Natural Non-Nutritive Sweetener Mogroside V

Background

Curcumin (CUR) is a functional ingredient from the spice turmeric. It has attracted considerable attention recently, owing to its diverse biological activities. However, curcumin has low water solubility, which limited its applications. Some sugar molecules were found to be able to solubilise poorly water-soluble compounds by forming micelles in aqueous solutions.

Purpose

To improve the water solubility and oral absorption of CUR, using a non-nutritive natural sweetener, namely, Mogroside V (Mog-V).

Methods

A solid dispersion of CUR in Mog-V was prepared using a solvent evaporation method. The solid dispersion was characterised by using X-ray diffraction and differential scanning calorimetry. The solid dispersion can dissolve in water to form micelles with a diameter of ~160 nm, which were characterised by using dynamic light scattering. To find out the mechanism of solubilisation, the aggregation behaviour of Mog-V molecules in aqueous solution was investigated using nuclear magnetic resonance spectroscopy. Finally, oral absorption of CUR in the solid dispersion was evaluated using a rodent model.

Results

A solid dispersion was formed in a ratio of 1 CUR to 10 Mog-V by weight. Upon dissolution into water, CUR laden micelles formed via self-assembly of Mog-V molecules, which increased the solubility of CUR by nearly 6000 times compared with pure CUR crystals. In rats, the solid dispersion increased the oral absorption of CUR by 29 folds, compared with CUR crystals. In terms of solubilisation mechanism, it was found that Mog-V self-assembled into micelles with a core-shell structure and CUR molecules were incorporated into the hydrophobic core of the Mog-V micelles.

Conclusion

Mog-V can form a solid dispersion with CUR. Upon dissolution in water, the Mog-V in the solid dispersion can self-assemble into micelles, which solubilise CUR and increase its oral absorption.

Plant Specialised Glycosides (PSGs): their biosynthetic enzymatic machinery, physiological functions and commercial potential

Plants, the primary producers of our planet, have evolved from simple aquatic life to very complex terrestrial habitat. This habitat transition coincides with evolution of enormous chemical diversity, collectively termed as 'Plant Specialised Metabolisms (PSMs)', to cope the environmental challenges. Plant glycosylation is an important process of metabolic diversification of PSMs to govern their in planta stability, solubility and inter/intra-cellular transport. Although, individual category of PSMs (terpenoids, phenylpropanoids, flavonoids, saponins, alkaloids, phytohormones, glucosinolates and cyanogenic glycosides) have been well studied; nevertheless, deeper insights of physiological functioning and genomic aspects of plant glycosylation/deglycosylation processes including enzymatic machinery (CYPs, GTs, and GHs) and regulatory elements are still elusive. Therefore, this review discussed the paradigm shift on genomic background of enzymatic machinery, transporters and regulatory mechanism of 'Plant Specialised Glycosides (PSGs)'. Current efforts also update the fundamental understanding about physiological, evolutionary and adaptive role of glycosylation/deglycosylation processes during the metabolic diversification of PSGs. Additionally, futuristic considerations and recommendations for employing integrated next-generation multi-omics (genomics, transcriptomics, proteomics and metabolomics), including gene/genome editing (CRISPR-Cas) approaches are also proposed to explore commercial potential of PSGs.

A review of transglycosylated compounds as food additives to enhance the solubility and oral absorption of hydrophobic compounds in nutraceuticals and pharmaceuticals

Transglycosylation has been used to modify the physicochemical properties of original compounds. As a result, transglycosylated compounds can form molecular aggregates in size ranges of a few nanometers in an aqueous medium when their concentrations exceed a specific level. Incorporating these hydrophobic compounds has been observed to enhance the solubility of hydrophobic compounds into aggregate structures. Thus, this review introduces four transglycosylated compounds as food additives that can enhance the solubility and oral absorption of hydrophobic compounds. Here, transglycosylated hesperidin, transglycosylated rutin, transglycosylated naringin, and transglycosylated stevia are the focus as representative substances. Significantly, we observed that amorphous formations containing hydrophobic compounds with transglycosylated compounds improved solubility and oral absorption compared to untreated hydrophobic compounds. Moreover, combining transglycosylated compounds with hydrophilic polymers or surfactants enhanced the solubilizing effects on hydrophobic compounds. Furthermore, the enhanced solubility of hydrophobic compounds improved their oral absorption. Transglycosylated compounds also influenced nanoparticle preparation of hydrophobic compounds as a dispersant. This study demonstrated the benefits of transglycosylated compounds in developing supplements and nutraceuticals of hydrophobic compounds with poor aqueous solubility.

Fast-Dissolving Solid Dispersions for the Controlled Release of Poorly Watersoluble Drugs

Solid dispersions offer many advantages for oral drug delivery of poorly water-soluble drugs over other systems, including an increase in drug solubility and drug dissolution. An improvement in drug absorption and the higher bioavailability of active pharmaceutical ingredients in the gastrointestinal tract have been reported in various studies. In certain circumstances, a rapid pharmacological effect is required for patients. Fastdissolving solid dispersions provide an ideal formulation in such cases. This report will provide an overview of current studies on fast-dissolving solid dispersions, including not only solid dispersion powders with fast dissolution rates but also specific dose form for the controlled release of poorly water-soluble drugs. Specifically, the applications of fast-dissolving solid dispersions will be described in every specific case. Moreover, pharmaceutical approaches and the utilization of polymers will be summarized. The classification and analysis of fastdissolving solid dispersions could provide insight into strategies and potential applications in future drug delivery developments.

Encapsulation of Hydrophobic and Low-Soluble Polyphenols into Nanoliposomes by pH-Driven Method: Naringenin and Naringin as Model Compounds

Naringenin and naringin are a class of hydrophobic polyphenol compounds and both have several biological activities containing antioxidant, anti-inflammatory and anti-tumor properties. Nevertheless, they have low water solubility and bioavailability, which limits their biological activity. In this study, an easy pH-driven method was applied to load naringenin or naringin into nanoliposomes based on the gradual reduction in their water solubility after the pH changed to acidity. Thus, the naringenin or naringin can be embedded into the hydrophobic region within nanoliposomes from the aqueous phase. A series of naringenin/naringin-loaded nanoliposomes with different pH values, lecithin contents and feeding naringenin/naringin concentrations were prepared by microfluidization and a pH-driven method. The naringin-loaded nanoliposome contained some free naringin due to its higher water solubility at lower pH values and had a relatively low encapsulation efficiency. However, the naringenin-loaded nanoliposomes were predominantly nanometric (44.95–104.4 nm), negatively charged (−14.1 to −19.3 mV) and exhibited relatively high encapsulation efficiency (EE = 95.34% for 0.75 mg/mL naringenin within 1% w/v lecithin). Additionally, the naringenin-loaded nanoliposomes still maintained good stability during 31 days of storage at 4 °C. This study may help to develop novel food-grade colloidal delivery systems and apply them to introducing naringenin or other lipophilic polyphenols into foods, supplements or drugs.

Exploring the effect of OSA-esterified waxy corn starch on naringin solubility and the interactions in their self-assembled aggregates

Octenyl succinic anhydride esterified waxy corn starches (OSAS) with five different molecular weights (MWs) were prepared by enzymatic hydrolysis and their effects on naringin solubility were studied. The MW of OSAS was found to significantly influence the amount of naringin embedded in the complex formed by self-aggregation. OSAS with medium MW (M-OSAS) formed complex with the highest naringin entrapment. This system showed an A_L type water phase solubility curve (indicating a 1:1 stoichiometric inclusion complex) and an increase of 848.83 folds in naringin solubility. Further investigation on the interactions between M-OSAS and naringin using FTIR, XRD, DSC and NMR confirmed the encapsulation of naringin into the inner cavity of M-OSAS. TEM and particle size analysis indicated the complex was spherical in shape, having a mean particle size of 257.07 nm and size distribution of 10-1000 nm. This study has provided a basis for solubility enhancement of citrus flavonoids using OSAS.