Solubility and thermodynamics of ferulic acid in different neat solvents: Measurement, correlation and molecular interactions

Enhancing the bioavailability and antioxidant activity of natamycin E235-ferulic acid loaded polyethylene glycol/carboxy methyl cellulose films as anti-microbial packaging for food application

This study investigated the development of biodegradable films made from a combination of polyethylene glycol (PEG), carboxymethyl cellulose (CMC) and mixtures from natamycin and ferulic acid. The films were characterized for their surface microstructure, antioxidant activity, thermal stability, mechanical properties, permeability and antifungal/bacterial activity. The addition of natamycin and ferulic acid to the film matrix enhanced antioxidant activity, thermal stability, antimicrobial activity, reduced the water vapor permeability (WVP) to 1.083 × 10-10 g × m-1s-1Pa-1, imparted opaque color and increased opacity up to 3.131 A mm-1. The attendance of natamycin and ferulic acid inside films created a clear roughness shape with agglomerates on the surface of films and caused a clear inhibition zone for Aspergillus niger, E. coli and C. botulinum. The utilization of PG/CMC/N-F packaging material on Ras cheese had a noticeable effect, resulting in a slight decrease in moisture content from 34.23 to 29.17 %. Additionally, it helped maintain the titrable acidity within the range of 0.99 % to 1.11 % and the force required for puncture from 0.035 to 0.052 N with non-significant differences. Importantly, these changes did not significantly affect the sensory qualities of Ras cheese during the storage period.

Polyhydroxybutyrate-co-hydroxyvalerate (PHBV) with Phenolic Acids for Active Food Packaging

PHBV films incorporating 3, 6 and 9% ferulic acid (FA) or p-coumaric acid (PCA) were obtained by melt blending and compression moulding. The films' microstructures and thermal behaviours were analysed as well as their mechanical, optical and barrier properties. The overall and specific migration of the materials in different food simulants was also characterised. FA was homogeneously mixed with the polymer, whereas PCA was mainly dispersed as fine particles in the PHBV matrices due to its higher melting point. These structural features promoted differences in the physical properties of the films depending on the compound concentration. As the concentration of both compounds rose, the barrier capacity of the films to oxygen, and to a lesser extent water vapour, was enhanced. While FA promoted the extensibility of the films, 9% PCA enhanced their brittleness. Both compounds affected the crystallisation pattern of the polymer, promoting smaller crystalline formations and a slight decrease in crystallinity. Although the overall migration of every film formulation was lower than the overall migration limit (OML), the release of active compounds was dependent on the food simulant; almost total release was noted in ethanol containing simulants but was more limited in aqueous systems. Therefore, these films could be used as food contact materials, contributing to extending the food's shelf life.

Time-Dependent Controlled Release of Ferulic Acid from Surface-Modified Hollow Nanoporous Silica Particles

Release of ferulic acid from surface-functionalized hollow nanoporous silica particles (HNSPs) was investigated in deionized water (DI water) and in ethanol. The host material, an HNSP, was synthesized in the presence of polymer and surfactant templates, and the pore as well as the surface were modified with either pentyltriethoxysilane (PTS) or octyltriethoxysilane (OTS) through silane coupling reactions. The inner hollow space occupied a volume of ~45% of the whole HNSP with a 2.54 nm pore channel in the wall. The pore size was estimated to decrease to 1.5 nm and 0.5 nm via the PTS and OTS functionalization, respectively. The encapsulation efficiencies of the HNSP (25 wt%), PTS-functionalized HNSP (PTS-HNSP, 22 wt%) and OTS-functionalized HNSP (OST-HNSP, 25 wt%) toward ferulic acid were similar, while the %release in DI water and ethanol varied following HNSP > PTS-HNSP > OTS-HNSP. Release kinetic analyses with Korsmeyer-Peppas fitting suggested a trade-off relationship between the solvent's ability to access the HNSP and the affinity of ferulic acid to the surface, allowing us to understand the solvent's controlled release rate and mechanism.

Protective effects of liposomes encapsulating ferulic acid against CCl4-induced oxidative liver damage in vivo rat model

Antioxidants are useful for the treatment of oxidative stress mediated liver damage. A naturally occurring antioxidant γ-oryzanol is rapidly hydrolyzed to its active hydrophobic metabolite, ferulic acid, inside the body. Limitations associated with the hydrophobicity of ferulic acid can be overcome by encapsulating in a liposomal formulation. As intravenously administered nanoparticles (including liposomes) can effectively reach the liver, such systems may be suitable drug delivery carriers to treat liver injury. In this study, we prepared a liposomal formulation of ferulic acid (ferulic-lipo) and examined its effects on liver damage induced by CCl₄. Ferulic-lipo were ~100 nm in size and drug encapsulation efficiency was about 92%. Ferulic-lipo showed potent scavenging efficacy against hydroxyl radical compared to α-tocopherol liposomes. Ferulic-lipo significantly prevented CCl₄-mediated cytotoxicity in human hepatocarcinoma cells. Furthermore, intravenous administration of ferulic-lipo significantly reduced alanine aminotransferase and aspartate amino transferase levels in a rat model of liver injury. CCl₄-mediated reactive oxygen species generation in liver was also reduced by intravenous administration of ferulic-lipo. Hepatoprotective effects of ferulic-lipo were demonstrated by histological observation of CCl₄-induced liver tissue damage. Therefore, ferulic-lipo exhibit potent antioxidative capacity and were suggested to be an effective formulation for prevention of oxidative damage of liver tissue.

Enhanced Antioxidant, Hyaluronidase, and Collagenase Inhibitory Activities of Glutinous Rice Husk Extract by Aqueous Enzymatic Extraction

In this research, we aimed to compare the biological activities related to cosmeceutical applications of glutinous rice husk extracted by aqueous enzymatic extraction (AEE) and conventional solvent extraction. Cellulase enzymes were used to assist the extraction process. The vanillic and ferulic acid contents of each extract were investigated by high-performance liquid chromatography, and their antioxidant and anti-aging activities were investigated by spectrophotometric methods. The irritation effects of each extract were investigated by the hen’s egg test on chorioallantoic membrane. The rice husk extract from AEE using 0.5% w/w of cellulase (CE0.5) contained the significantly highest content of vanillic and ferulic acid (p < 0.05), which were responsible for its biological activities. CE0.5 was the most potent antioxidant via radical scavenging activities, and possessed the most potent anti-skin wrinkle effect via collagenase inhibition. Aside from the superior biological activities, the rice husk extracts from AEE were safer than those from solvent extraction, even when 95% v/v ethanol was used. Therefore, AEE is suggested as a green extraction method that can be used instead of the traditional solvent extraction technique given its higher yield and high quality of bioactive compounds. Additionally, CE0.5 is proposed as a potential source of natural antioxidants and anti-aging properties for further development of anti-wrinkle products.

Optimization of Phenolic Compound Extraction from Brewers’ Spent Grain Using Ultrasound Technologies Coupled with Response Surface Methodology

Brewers’ spent grain (BSG) is the main solid by-product from the brewery industry, rich in valuable nutrients and bioactive compounds. The aim of this study was to valorize this by-product, recovering phenolic compounds from BSG using ultrasound-assisted extraction (UAE) and chemometric techniques, such as the response surface methodology (RSM). Therefore, UAE process parameters (temperature and time) and solvent composition (ethanol aqueous mixtures) were optimized using a three-level Box–Behnken design, in order to carry out the maximum yield in phenols. Then, the extract obtained under optimal conditions was characterized for the total phenolic content and antioxidant capacity (2,20-azino-bis(3-ethylbenothiazoline-6-sulphonic acid, ABTS, and 2,2-diphenyl-1-picrylhydrazyl, DPPH), and individual phenolic compounds were identified using HPLC-DAD. The results show the highest level of total soluble phenolic content (4.1 ± 0.1 mg GAE/g d.w.) at 80 °C, 50 min and 65:35% ethanol:water, with a high goodness of fit between experimental and predicted values (R2 = 0.987), and a high antioxidant potential (DPPH: 0.42 ± 0.01 mg TE eq/g d.w.; ABTS: 5.82 ± 0.04 mg TE eq/g d.w.). A comparison between the classic extraction techniques and the UAE with the same solvent showed an increase of 156% in the phenol yield. The characterization of phenolic profile revealed that ferulic acid (1.5 ± 0.2 mg/L), vanillic acid (0.78 ± 0.18 mg/L) and p-coumaric acid (0.12 ± 0.03 mg/L) were the prevalent ones. UAE coupled with RSM was a useful tool to inexpensively and quickly recover bioactive phenolic compounds from BSG, which can be used in the food, pharmaceutical or cosmetic industries.

Thermodynamic Solubility Profile of Temozolomide in Different Commonly Used Pharmaceutical Solvents

The solubility parameters, and solution thermodynamics of temozolomide (TMZ) in 10 frequently used solvents were examined at five different temperatures. The maximum mole fraction solubility of TMZ was ascertained in dimethyl sulfoxide (1.35 × 10⁻²), followed by that in polyethylene glycol-400 (3.32 × 10⁻³) > Transcutol^® (2.89 × 10⁻³) > ethylene glycol (1.64 × 10⁻³) > propylene glycol (1.47 × 10⁻³) > H₂O (7.70 × 10⁻⁴) > ethyl acetate (5.44 × 10⁻⁴) > ethanol (1.80 × 10⁻⁴) > isopropyl alcohol (1.32 × 10⁻⁴) > 1-butanol (1.07 × 10⁻⁴) at 323.2 K. An analogous pattern was also observed for the other investigated temperatures. The quantitated TMZ solubility values were regressed using Apelblat and Van’t Hoff models and showed overall deviances of 0.96% and 1.33%, respectively. Apparent thermodynamic analysis indicated endothermic, spontaneous, and entropy-driven dissolution of TMZ in all solvents. TMZ solubility data may help to formulate dosage forms, recrystallize, purify, and extract/separate TMZ.

Modeling the Solubility of Phenolic Acids in Aqueous Media at 37 °C

In this work, the solubility of vanillic, gallic, syringic, p-coumaric, ferulic and caffeic acids was determined at 37 °C under different conditions, namely pure water and two different ionic media, NaCl(aq) and NaClO₄(aq), at different ionic strengths (i.e., 0.16, 0.50, 1.0, 2.0 and 3.0 M). The solubility in water of all the acids was found to be higher than that in both of the ionic media. Moreover, the solubility of hydroxycinnamic acids was lower than that of hydroxybenzoic acids. The activity coefficients of neutral species were calculated from these data; this knowledge is necessary when modeling the dependence of equilibrium constants on the ionic strength. Results obtained in this work can be useful for further studies regarding complex formation equilibria between these ligands and bioavailable metal cations.

Ferulic Acid Activity in Topical Formulations: Technological and Scientific Prospecting

INTRODUCTION

Ferulic acid is a phenolic compound widely distributed in monocotyledons, with several applications, especially in pharmaceutical and dermo-cosmetic industries. It has proven antioxidant and anti- inflammatory activities, among others, which are mainly ascribed to its molecular structure. The main factor that can lead to serious skin damages like inflammation, dryness, wrinkles, and cancer is the exposure to UV radiation that is responsible for an increased level of radical oxygen species.

OBJECTIVE

This review aims to evaluate the application of ferulic acid in topical formulations and the technologies used to enhance its bioavailability and stability, as well as to get a clearer picture of its effects by in vivo and in vitro studies.

METHODS

It covers technological publications in the WIPO, EPO, INPI, and USPTO databases and scientific publications in the PubMed, Web of Sciences, and Science Direct databases, exploring the trend and application of this compound by country and year of publication.

RESULTS

Both the scientific and technological analyses showed the importance and tendency in the association of the Ferulic Acid and other vitamins and actives. The synergic effect certainly provides a better result, performance, and stability of the compounds, which cleared the great spectrum and applicability of the Ferulic Acid in topical formulations.

CONCLUSION

The present literature survey revealed that ferulic acid exerts an important activity in several formulations for topical application and improved the stability and bioavailability when combined with new technologies and methods, showing an open path to target the treatment of skin disorders.

Antifungal Activity against Botryosphaeriaceae Fungi of the Hydro-Methanolic Extract of Silybum marianum Capitula Conjugated with Stevioside

Silybum marianum (L.) Gaertn, viz. milk thistle, has been the focus of research efforts in the past few years, albeit almost exclusively restricted to the medicinal properties of its fruits (achenes). Given that other milk thistle plant organs and tissues have been scarcely investigated for the presence of bioactive compounds, in this study, we present a phytochemical analysis of the extracts of S. marianum capitula during the flowering phenological stage (stage 67). Gas chromatography–mass spectroscopy results evidenced the presence of high contents of coniferyl alcohol (47.4%), and secondarily of ferulic acid ester, opening a new valorization strategy of this plant based on the former high-added-value component. Moreover, the application of the hydro-methanolic extracts as an antifungal agent has been also explored. Specifically, their activity against three fungal species responsible for the so-called Botryosphaeria dieback of grapevine (Neofusicoccum parvum, Dothiorella viticola and Diplodia seriata) has been assayed both in vitro and in vivo. From the mycelial growth inhibition assays, the best results (EC₉₀ values of 303, 366, and 355 μg·mL⁻¹ for N. parvum, D. viticola, and D. seriata, respectively) were not obtained for the hydroalcoholic extract alone, but after its conjugation with stevioside, which resulted in a strong synergistic behavior. Greenhouse experiments confirmed the efficacy of the conjugated complexes, pointing to the potential of the combination of milk thistle extracts with stevioside as a promising plant protection product in organic Viticulture.

Thermodynamic solubility and solvation behavior of ferulic acid in different (PEG-400 + water) binary solvent mixtures

This work was carried out to determine solubility, solution thermodynamics, solvation behavior, and molecular interactions of a natural compound ferulic acid (FLA) in different '[polyethylene glycol-400 (PEG-400) + water]' binary solvent mixtures at 'T = 298.2 K to 318.2 K' and 'p = 0.1 MPa.' The mole fraction solubilities (x_e) of FLA were determined by liquid chromatographic technique using a static equilibrium technique. The obtained solubility data of FLA were regressed using 'Van't Hoff, Apelblat, Yalkowsky-Roseman and Jouyban-Acree models.' The solubility of FLA (expressed in mole fraction) was enhanced with elevation in absolute temperature in each 'PEG-400 + water' binary solvent mixture evaluated. The maximum x_e values of FLA were recorded in neat PEG-400 (1.94 × 10^-1) at 'T = 318.2 K.' While, the minimum one was obtained in neat water (4.90 × 10^-5) at 'T = 298.2 K.' The molecular interactions between FLA-PEG-400 and FLA-water were obtained by determination of activity coefficients of FLA in different 'PEG-400 + water' binary solvent mixtures. The physical data of activity coefficients recorded in this work suggested strong molecular interactions in FLA-PEG-400 in comparison with FLA-water. 'Apparent thermodynamic analysis' suggested an 'endothermic and entropy-driven dissolution' of FLA in each 'PEG-400 + water' binary solvent mixture investigated.

Measurements, Thermodynamic Modeling, and a Hydrogen Bonding Study on the Solubilities of Metoprolol Succinate in Organic Solvents

The solubilities of metoprolol succinate (a cardioselective β1 adrenergic receptor) in methanol, ethanol, n-propanol, isopropanol, n-butanol, ethyl acetate, and acetone were measured at temperatures ranging from (278.2 to 318.2) K using a solid–liquid equilibrium method. The solubility of metoprolol succinate increases with increasing temperature. At a fixed temperature, the solubility decreases in the order methanol > ethanol > n-butanol > n-propanol > isopropanol > acetone > ethyl acetate. The enthalpy of fusion and the melting point of metoprolol succinate were determined by differential scanning calorimetry. The thermodynamic properties of the dissolution process, determined by a van’t Hoff analysis, have been obtained and are discussed. The modified Apelblat equation, Wilson model, and non-random two-liquid (NRTL) model were employed to correlate the solubilities of metoprolol succinate in different solvents. Finally, a quantitative structure–property relationship (QSPR) study of physical properties of solvents and density functional theory simulations of hydrogen-bonding structure were carried out to give the explanation for the sequence of solubility in alcohols. The density functional theory (DFT) calculations well illustrated that the solubility of metoprolol succinate in various alcohols can be mainly attributed to the intra- and intermolecular hydrogen bonds in metoprolol succinate-solvent complexes.

Solubility determination of raloxifene hydrochloride in ten pure solvents at various temperatures: Thermodynamics-based analysis and solute-solvent interactions

The purpose of the present study was to determine the solubility of raloxifene hydrochloride (RHCl) in ten solvents: water, ethanol, isopropyl alcohol (IPA), ethylene glycol (EG), propylene glycol (PG), polyethylene glycol-400 (PEG-400), Transcutol, 1-butanol, dimethyl sulfoxide (DMSO), and ethyl acetate (EA) at temperatures of 298.2-323.2 K and a pressure of 0.1 MPa. The solubility data obtained was fitted upon "Apelblat and Van't Hoff" equations. The maximum mole fraction solubility of RHCl was obtained in DMSO (5.02 × 10^-2 at 323.2 K), followed by PEG-400 (5.92 × 10^-3 at 323.2 K), EA (3.11 × 10^-3 at 323.2 K), Transcutol (1.22 × 10^-3 at 323.2 K), PG (2.19 × 10^-4 at 323.2 K), 1-butanol (1.96 × 10^-4 at 323.2 K), IPA (1.47 × 10^-4 at 323.2 K), ethanol (7.90 × 10^-5 at 323.2 K), EG (6.65 × 10^-5 at 323.2 K), and water (3.60 × 10^-5 at 323.2 K). Similar fashions were noticed at each studied temperature. The higher solubility of RHCl in DMSO, PEG-400, EA, and Transcutol was possibly referable to their lower polarity in comparison with water. The molecular interactions between the solute and solvent molecules were estimated by calculating parameters like activity coefficients, and more prominent solute-solvent molecular interactions were noted for RHCl-DMSO, RHCl-EA, and RHCl-PEG-400 in comparison with the other solute-solvent combinations. The outcomes of the "apparent thermodynamic analysis" showed that the dissolution of RHCl was "endothermic, spontaneous and entropy-driven" in all investigated solvents. The obtained solubility data of RHCl in commonly used solvents could be useful in the purification, recrystallization, and dosage form design of the drug.

Pulsed electric field-assisted sensitization of multidrug-resistant Candida albicans to antifungal drugs

AIM

Determine the influence of pH on the inactivation efficiency of Candida albicans in pulsed electric fields (PEF) and evaluate the possibilities for sensitization of a drug-resistant strain to antifungal drugs.

MATERIALS & METHODS

The effects of PEF (2.5-25 kVcm^-1) with fluconazole, terbinafine and naftifine were analyzed at a pH range of 3.0-9.0. Membrane permeabilization was determined by flow cytometry and propidium iodide.

RESULTS

PEF induced higher inactivation of C. albicans at low pH and increased sensitivity to terbinafine and naftifine to which the strain was initially resistant. Up to 5 log reduction in cell survival was achieved.

CONCLUSION

A proof of concept that electroporation can be used to sensitize drug-resistant microorganisms was presented, which is promising for treating biofilm-associated infections.

Solubility and molecular interactions of ferulic acid in various (isopropanol + water) mixtures

OBJECTIVE

The solubility of an herbal compound ferulic acid (FA) in various (isopropanol (IPA) + water) mixtures was measured and correlated at temperatures 'T = 298.2 K to 318.2 K' and pressure 'p = 0.1 MPa'.

METHODS

The experimental solubilities of FA in mole fraction were determined using a static equilibrium method and correlated with 'Apelblat, Van't Hoff, Yalkowsky and Jouyban-Acree models'.

KEY FINDINGS

The maximum mole fraction solubilities of FA were obtained in neat IPA (2.58 × 10^-2 at T = 318.2 K) followed by minimum in neat water (4.87 × 10^-5 at T = 298.2 K). The activity coefficients of FA in various (IPA + water) mixtures were determined to evaluate the molecular interactions between FA and co solvent mixtures. Strong molecular interactions were seen between FA and neat IPA in comparison with FA and neat water. 'Apparent thermodynamic analysis' indicated an 'endothermic and entropy-driven dissolution' of FA in all (IPA + water) mixtures evaluated.

CONCLUSIONS

Isopropanol was investigated as a good cosolvent in the solubility enhancement of FA in water; therefore, it could be used as solubilizer in solubility enhancement and formulation development of FA.