Effect of β-sitosterol on the curcumin-loaded liposomes: Vesicle characteristics, physicochemical stability, in vitro release and bioavailability

Stability characterization for pharmaceutical liposome product development with focus on regulatory considerations: An update

Liposomes have several advantages, such as the ability to be employed as a carrier/vehicle for a variety of drug molecules and at the same time they are safe and biodegradable. In the recent times, compared to other delivery systems, liposomes have been one of the most well-established and commercializing drug products of new drug delivery methods for majority of therapeutic applications. On the other hand, it has several limitations, particularly in terms of stability, which impedes product development and performance. In this review, we reviewed all the potential instabilities (physical, chemical, and biological) that a formulation development scientist confronts throughout the development of liposomal formulations as along with the ways to overcome these challenges. We have also discussed the effect of microbiological contamination on liposomal formulations with a focus on the use of sterilization methods used to improve the stability. Finally, we have reviewed quality control techniques and regulatory considerations recommended by the agencies (USFDA and MHLW) for liposome drug product development.

Liposomal β-Sitosterol Suppresses Metastasis of CT26/luc Colon Carcinoma via Inhibition of MMP-9 and Evoke of Immune System

β-sitosterol (SITO) has been reported with anticancer effects; however, with poor bioavailability. The current study aimed to investigate whether liposomal encapsulated β-sitosterol (LS) has a better inhibition effect on tumor metastasis than β-sitosterol in a CT26/luc lung metastasis mouse model and the possible underlying mechanism. LS was liposomal-encapsulated SITO and was delivered to mice by oral gavage. The cell viability was determined by the MTT assay, and invasiveness of the tumor cells and related protein expression were evaluated with the invasion assay and Western blotting. For therapeutic efficacy evaluation, male BALB/c mice were treated with PBS, SITO, and LS once a day for 7 days prior to intravenous injections of CT26/luc cells; treatments were continued twice a week post-cell inoculation throughout the entire experiment. Tumor growth inhibition was monitored by bioluminescent imaging (BLI). IL-12, IL-18, and IFN-γ in the intestinal epithelium were determined by ELISA. The results show that LS treatment had a better invasion inhibition with lower cytotoxicity than SITO when the same dose was utilized. Notably, mice treated with LS significantly exhibited fewer metastases to the lungs and other tissues/organs compared with the Control and SITO groups. Additionally, the IL-12, IL-18, and IFN-γ levels were significantly increased in the LS-treated mice compared with the Control and SITO groups. The underlying mechanism may be through the inhibition of MMP-9 and elicitation of the antitumoral Th1 immune response, such as increasing CD4⁺ and CD8⁺ T cells, IL-12, IL-18, and IFN-γ.

Inulin-Modified Liposomes as a Novel Delivery System for Cinnamaldehyde

Cinnamaldehyde as an antioxidant was encapsulated in inulin-modified nanoliposomes in order to improve its physical and antioxidant stability. The microstructure, particle size and volume distribution of cinnamaldehyde liposomes were characterized by atomic force microscopy (AFM) and dynamic light scattering (DLS). The particle size and polydispersion index (PDI) values of the inulin modified liposomes were 72.52 ± 0.71 nm and 0.223 ± 0.031, respectively. The results showed that the liposomes after surface modification with inulin remained spherical. Raman and Fourier transform infrared (FTIR) spectra analysis showed that hydrogen bonds were formed between the inulin and the liposome membrane. Inulin binding also restricted the freedom of movement of lipid molecules and enhanced the order of the hydrophobic core of the membrane and the polar headgroup region in lipid molecules. Therefore, the addition of different concentrations of inulin influenced the permeability of the liposome bilayer membrane. However, when inulin was excessive, the capacity of the bilayer membrane to load the cinnamaldehyde was reduced, and the stability of the system was reduced. Additionally, the encapsulation efficiency (EE) and retention rate (RR) of cinnamaldehyde from inulin-modified liposomes during storage were determined. The EE value of the inulin modified liposomes was 70.71 ± 0.53%. The liposomes with 1.5% inulin concentration had the highest retention rate (RR) and the smallest particle size during storage at 4 °C. The addition of inulin also enhanced the thermal stability of the liposomes. Based on the results, the surface modification improved the oxidation stability of liposomes, especially the DPPH scavenging ability. In conclusion, these results might help to develop inulin as a potential candidate for the effective modification of the surface of liposomes and provide data and conclusions for it.

Co-encapsulation of Curcumin and Boswellic Acids in Chitosan-Coated Niosome: An In-vitro Digestion Study

AIM

In this study chitosan-coated niosome (ChN) was utilized for bioavailability enhancement of curcumin (Cn) and boswellic acids (BAs).

METHODS

The bare niosome (BN) was prepared by the heating method and optimized by using the mixture design procedure. Physicochemical stability, as well as the in vitro release, and bioavailability of Cn and BAs in BN and ChN were studied.

RESULTS

The optimized BN had a mean diameter of 70.00 ± 0.21 nm and surface charge of -31.00 ± 0.25 mv, which changed to 60.01 ± 0.20 nm and +40.00 ± 0, respectively, in ChN. In-vitro digestion study revealed chitosan layer augmented the bioavailability of Cn and BAs to 79.02 ± 0.13 and 81 ± 0.10, respectively. The chitosan layer obviously improved the physical stability of Cn and BA in the niosome vehicle, by means of vesicle size, zeta potential, and encapsulation efficiency.

CONCLUSION

The Chitosan-coated niosome was considered to be promising delivery system for increasing the bioavailability of Cn and BAs.

Preparation and pharmacokinetics in vivo of linarin solid dispersion and liposome

Objective

The current investigation aimed to determine the appropriate dosage form by comparing solid dispersion and liposome to achieve the purpose of improving the solubility and bioavailability of linarin.

Methods

Linarin solid dispersion (LSD) and linarin liposome (LL) were developed via the solvent method and the thin film hydration method respectively. The Transwell chamber model of Caco-2 cells was established to evaluate the absorption of drug. The pharmacokinetics of linarin, LSD and LL in rats after ig administration were carried out by high performance liquid chromatography (HPLC) method.

Results

The solubility of LSD and LL was severally 3.29 times and 3.09 times than that of linarin. The permeation coefficients of LSD and LL were greater than 10⁻⁶, indicating that the absorption of LSD and LL were both better than linarin. The bioavailability of the LSD was 3.363 times higher than that of linarin, and the bioavailability of LL was 0.9886 times higher than that of linarin.

Conclusion

The linarin was more suitable for making solid dispersion to enhance its solubility and bioavailability.

Improving norbixin dispersibility and stability by liposomal encapsulation using the pH-driven method

BACKGROUND

Norbixin, a carotenoid extracted from annatto seeds, is widely utilized as a natural pigment in foods, cosmetics and medicines. Its water solubility is relatively high under neutral or alkaline conditions but low under acidic conditions, which limits its application in some food products.

RESULTS

This problem was overcome by utilizing liposomes to encapsulate the carotenoids so that they could be easily dispersed within acidic solutions. The norbixin was loaded into the liposomes using the pH-driven method. Liposomes were produced by passing aqueous phospholipid dispersions through a microfluidizer under high pressure. Norbixin was then added to the liposome dispersions at pH 7.0 and then driven into the hydrophobic domains of the phospholipid bilayers by acidifying the system. Measurements of the encapsulation efficiency showed that the norbixin was successfully loaded into the liposomes using the pH-driven method. X-ray diffraction analysis showed that the norbixin was in an amorphous state after incorporation into the liposomes. Encapsulation of norbixin within the liposomes was also shown to increase its water dispersibility and chemical stability under acidic pH conditions.

CONCLUSION

The pH-driven method therefore provides a useful means of increasing the application of this bioactive carotenoid within functional foods and other products. © 2021 Society of Chemical Industry.

Production, Characterization, Delivery, and Cholesterol-Lowering Mechanism of Phytosterols: A Review

Phytosterols are natural plant-based bioactive compounds that can lower blood cholesterol levels and help prevent cardiovascular diseases. Consequently, they are being utilized in functional foods, supplements, and pharmaceutical products designed to improve human health. This paper summarizes different approaches to isolate, purify, and characterize phytosterols. It also discusses the hypolipidemic mechanisms of phytosterols and their impact on cholesterol transportation. Phytosterols have a low water-solubility, poor chemical stability, and limited bioavailability, which limits their utilization and efficacy in functional foods. Strategies are therefore being developed to overcome these shortcomings. Colloidal delivery systems, such as emulsions, oleogels, liposomes, and nanoparticles, have been shown to be effective at improving the water-dispersibility, stability, and bioavailability of phytosterols. These delivery systems can be used to incorporate phytosterols into a broader range of cholesterol-lowering functional foods and beverages. We also discuses several issues that need to be addressed before these phytosterol delivery systems can find widespread commercial utilization.

Preparation and Characterization of a Novel Soy Protein Isolate-Sugar Beet Pectin Emulsion Gel and Its Application as a Multi-Phased Nutrient Carrier

Emulsion gel, a novel oral delivery carrier, provides the possibility to co-load hydrophilic and lipophilic nutrients simultaneously. In this study, duo-induction methods of laccase and glucono-δ-lactone (L&GDL) or laccase and transglutaminase (L&MTG) were used to prepare the soy protein isolate-sugar beet pectin (SPI-SBP) emulsion gel. The textural data of the emulsion gel was normalized to analyze the effect of different induction methods on the gel property of the SPI-SBP emulsion gels. The characterization studies showed the structure of L&MTG emulsion gel was denser with a lower swelling ratio and reduced degree of digestion, compared with L&GDL emulsion gel. Moreover, the release profiles of both β-carotene and riboflavin co-loaded in the SPI-SBP emulsion gels were correlated to the digestion patterns of the gel matrix; the controlled-release of encapsulated functional factors was regulated by a gel network induced by different induction methods, mainly due to the resulting porosity of the structure and swelling ratio during digestion. In conclusion, SPI-SBP emulsion gels have the capability of encapsulating multiple functional factors with different physicochemical properties.

DHA loaded nanoliposomes stabilized by β-sitosterol: Preparation, characterization and release in vitro and vivo

DHA loaded nanoliposomes, stabilized by β-sitosterol, were prepared by thin film hydration-sonication method. The characteristics and membranes properties of DHA-NLs with different β-sitosterol content were measured. The samples with the same formulation were used to measure the resistance of environment stress and controlled release & absorption of DHA in vitro and in vivo. The results showed that the maximal encapsulation efficiency of DHA-NLs was (86.95 ± 0.95)%, when the ratio of soybean lecithin to β-sitosterol was 5:1. The particle size of all samples was within 200 nm and relative retention rate was more than 60% after 3 weeks storage. The area under the curve of DHA concentration of DHA-NLs and DHA-emulsion groups was 1.32 and 1.08, respectively. In summary, the nanoliposomes were promising to improve the absorption of DHA in form of ethyl ester.

Inspiring biomimetic system based on red blood cell membrane vesicles for effective curcumin loading and release

The aim of this study is to introduce an inspiring biomimetic system based on the red blood cell membrane (RBCM) vesicles for improved encapsulation efficiency and release of curcumin (Cur). Here, the role of the sonication time (0.5, 1.5, 3 and 5 min) on the properties of RBCM-CUR vesicles is investigated. It is determined that the hydrodynamic vesicle size, zeta potential, and release behavior are tunable by changing the sonication time. Noticeably, the average size of vesicles decreased from 163.0 ± 21 nm to 116.3 ± 16 nm by increasing the sonication time from 0.5 to 5 min. Moreover, the drug release value, after 24 h incubation, enhances from 57 to 99% with the expansion of sonication from 0.5 to 5 min. Additionally, the entrapment efficiency of Cur as a model drug is high in whole sonication time, owing to the amphiphilic nature of RBCM. Finally, the RBCM-CUR vesicles are not only cytocompatible, but also could support the attachment and proliferation of fibroblast cells in vitro. The RBCM based system for delivery of Cur could be a promising system for the wound healing applications.

Near-Infrared Light-Responsive SERS Tags Enable Positioning and Monitoring of the Drug Release of Photothermal Nanomedicines In Vivo

Understanding the in vivo behavior of photothermal nanomedicines (PTNMs) is important for drug development and evaluation. However, it is still very challenging. Herein, two key parameters, i.e., the depth of PTNMs under biological tissue and the drug release ratio of PTNMs in vivo, can be revealed by a near-infrared (NIR) light-responsive surface-enhanced Raman scattering (SERS) strategy. The fabricated PTNMs were composed of waxberry-like gold nanoparticles, model drug curcumin, and an elaborately selected NIR light-responsive Raman reporter (3,3'-diethylthiatricarbocyanine iodide, DTTC). The response mechanism of DTTC to NIR light was investigated as photodegradation. NIR light irradiation heated the gold nanoparticles, triggered the release of a model drug, and simultaneously decreased the SERS intensity of the PTNMs. In vitro experiment results revealed that the SERS intensity decrease could well reflect the depth of PTNMs with a correlation coefficient of more than 0.99. On this basis, after in situ SERS detection, the depth of PTNMs in a tumor could be revealed with satisfactory accuracy. Moreover, the decrease in the SERS intensity of PTNMs showed a highly similar trend to the increase in the drug release, suggesting that it could be used for real-time monitoring of drug release of PTNMs. This study not only opens a new avenue for the release study of many inactive fluorescent and Raman drugs of PTNMs but also provides an effective way for reporting the depth, which greatly promotes the application of PTNMs in vivo.

Effect of Galangal Essential Oil Emulsion on Quality Attributes of Cloudy Pineapple Juice

Galangal essential oil is obtained from the rhizomes of galangal with proven anti-inflammatory, antioxidant, antiviral, and antimicrobial properties, which are valuable in the food industry. To explore the effect of galangal essential oil on the quality of pineapple juice, 0.05, 0.1, 0.2, and 0.4% galangal essential emulsion were added, and their influence on the physical stability, physicochemical properties, microbial quantity, and aroma profiles of cloudy pineapple juice were evaluated. The essential oil emulsion of galangal is a milky white liquid with a strong aroma of galangal. The pH values of emulsion increased from 4.35 to 5.05 with the increase in essential oil concentration, and there was no significant difference in the particle size of the pineapple juice. The results showed that the galangal essential oil emulsion was stable and the stability of the cloudy pineapple juice was significantly enhanced by the essential oil emulsion determined using LUMiSizer. The cloudy pineapple juice with a 0.2% essential oil emulsion showed the most stability during storage. The lightness of the cloudy pineapple juice increased instantly with the essential oil emulsion addition. In addition, the microbial quantity of the cloudy pineapple juice was decreased by the individual essential oil emulsion or combined with thermal treatment to hold a longer shelf life. The microbial counts in pineapple juice treated by 0.4% essential oil emulsion and thermal treatment only increased from 1.06 to 1.59 log CFU/ml after 4 days of storage at 25°C. Additionally, the pH and total soluble solids showed a slightly increasing trend; however, the value of titratable acidity, free radical scavenging capacity, and ascorbic acid content of the cloudy pineapple juice showed no significant change. Finally, the results of the electronic nose showed that the aroma components of the pineapple juice were changed by the essential oil emulsion and thermal treatment, and the difference was especially evident in the content of the sulfur, sulfur organic, and aromatics compounds. Consequently, the results indicated that galangal essential oil emulsion can be used as juice additives to improve the quality attributes and extend the shelf-life of cloudy pineapple juice.

Construction of Hohenbuehelia serotina polysaccharides-mucin nanoparticles and their sustain-release characteristics under simulated gastrointestinal digestion in vitro

In this study, Hohenbuehelia serotina polysaccharides-mucin nanoparticles (HSP-MC NPs) were fabricated based on hydrogen bonding and hydrophobicity effects for improving the bioavailability of HSP. The structural characteristics and morphology of HSP-MC NPs prepared by different conditions were respectively identified and observed. The results showed that HSP-MC NPs (HSP/MC, 1/1, w/w) presented the optimal physicochemical characteristics, with the encapsulation efficiency of 88.09 ± 0.01%, average particle size of 509.4 ± 9.76 nm and zeta potential of -20.6 ± 0.7 mV. Furthermore, HSP-MC NPs (HSP/MC, 1/1, w/w), belonged to non-crystalline substances, exhibited the excellent physicochemical stabilities against temperature, pH and ionic strength, and had the uniform spherical morphological characteristics. In addition, under simulated gastrointestinal digestion in vitro, HSP-MC NPs (HSP/MC, 1/1, w/w) showed the good sustained release performances, that might effectively improve the absorption rate of HSP. The present research is meaningful for designing the polysaccharides-loaded nano-delivery system based on natural non-toxic carrier that can be used in function food field.

Chemical Characterization of Chinese Perilla Seed Oil

Physicochemical properties and chemical composition of Chinese perilla seed oil has been characterized in this study. The result showed that both the cold press oil and the solvent extracted oil possessed low acid value and peroxide value. The fatty acid composition result showed that the oil has high content of linolenic acid (C18:3) up to 66.4 g/100 g, followed by linoleic acid (C18:2) of 15.3 g/100 g. The total triacylglycerol (TAG) profiles results showed that the oil contained 20 TAGs including 17 regioisomers, including LnLnLn (35.8 g/100 g), LLnLn (20.2 g/100 g), LLLn (17.7 g/100 g) and PLnLn (14.9 g/100 g) (Ln, linolenic acid; L, linoleic acid; P, palmitic acid). With content of only 0.57 g/100 g oil, the unsaponifiable matters were mainly composed of phytosterols, squalene, tocopherol, alcohols and hydrocarbons. The total phytosterols content was 0.39 g/100 g oil, in which β-sitosterol has high content of 0.31 g/100 g oil.

Improved skin permeability and whitening effect of catechin-loaded transfersomes through topical delivery

The aim of the study was to prepare catechin-loaded transfersomes to enhance drug permeability through topical administration for the skin protection against ultraviolet radiation induced photo-damage. The results showed that the catechin-loaded transfersomes were monodispersed with polydispersity index (PDI) < 0.2, <200 nm in particle size and with high encapsulation efficiency (E.E.%) greater than 85%. The in vitro skin permeation test indicated that the catechin-loaded transfersomes enhanced the skin permeability by 85% compared to the catechin aqueous solution. Similarly, the in-vivo skin whitening study demonstrated that F5 transfersome formulation was effective in tyrosinase inhibition and had good biocompatibility to the guinea pig skin. Finally, the stability study showed that both physicochemical properties and E.E.% of the F5 transferosome formulation were fairly stable after 3 months storage. Therefore, topical administration of catechin-loaded transfersomes could be considered as a potential strategy for the treatment of UV-induced oxidative damage to the skin.

Effects of Phytosterol Butyrate Ester on the Characteristics of Soybean Phosphatidylcholine Liposomes

The nutritional and structural properties of phytosterols (PS)/phytosterol esters (PEs) facilitate their use as substitutes for cholesterol in liposome encapsulation systems designed for oral drugs and health products. The purpose of this study was to determine the effect of phytosterol butyrate ester (PBE) on the properties of liposomes. PBE was encapsulated within liposomes (approximately 60 nm) prepared using soybean phosphatidylcholine using the thin-film hydration method. There was no significant change in the average particle diameter and zeta potential of these liposomal vesicles corresponding to the increasing amounts of encapsulated PBE. The incorporation of PBE increased the polydispersity index (PDI) independent of concentration. Additionally, we observed that the storage stability of PBE liposomes with uniform particle size and approximately spherical shape vesicle was better at low concentration. The results of Fourier-transform infrared (FTIR) spectroscopy and Raman spectroscopy showed that PBE was positioned at the water interface, which increased the order of hydrophobic alkyl chains in the lipid membranes. The incorporation of PBE led to an increase in the trans conformation of hydrophobic alkyl chain and consequently, the thermal stability of liposomes, which was confirmed by differential scanning calorimetry (DSC). The results of powder X-ray diffraction (XRD) analysis confirmed that PBE was present in an amorphous form in the liposomes. Additionally, the incorporation of PBE reduced the micropolarity of the lipid membrane. Thus, when preparing liposomes using thin-film hydration, the presence of PBE affected the characteristics of liposomes.

PEGylated dihydromyricetin-loaded nanoliposomes coated with tea saponin inhibit bacterial oxidative respiration and energy metabolism

The biofilms produced by the aggregation of bacterial colonies are among the major obstacles of host immune system monitoring and antimicrobial treatment. Herein, we report PEGylated dihydromyricetin-loaded liposomes coated with tea saponin grafted on chitosan (TS/CTS@DMY-lips) as an efficient cationic antibacterial agent against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), which is supported by their deep penetration into bacterial biofilms and broad pH-stable release performance of dihydromyricetin (DMY). The successful construction of the drug delivery system relied on tea saponin grafted on chitosan (TS/CTS) via formatted ester bonds or amido bonds as a polyelectrolyte layer of PEGylated dihydromyricetin-loaded liposomes (DMY lips), which achieved controlled release of DMY in weak acidic and neutral physiological environments. The micromorphology of TS/CTS@DMY-lips was observed to resemble dendritic cells with an average size of 266.49 nm, and they had excellent encapsulation efficiency (41.93%), water-solubility and stability in aqueous solution. Besides, TS/CTS@DMY-lips displayed effective destruction of bacterial energy metabolism and cytoplasmic membranes, resulting in the deformation of the cell wall and leaking of cytoplasmic constituents. Compared to free DMY, DMY lips and chitosan-coated dihydromyricetin liposomes (CTS@DMY-lips), TS/CTS@DMY-lips has more thorough killing activity against E. coli and S. aureus, which is related to its excellent sustained release performance of DMY under the protection of the TS/CTS coating.

Suppression of palmitic acid-induced hepatic oxidative injury by neohesperidin-loaded pectin-chitosan decorated nanoliposomes

The biological activity of neohesperidin (NH, a flavanone glycoside) is limited due to instability in the physiological environment. Thus, the current study aimed to explore the protective effect of NH-loaded pectin-chitosan decorated liposomes (P-CH-NH-NL) against palmitic acid (PA)-induced hepatic oxidative injury in L02 cells. The particles were characterized using DLS, TEM, HPLC, DSC, and cellular uptake study. Then, the protective effect of NH-loaded liposomal systems (NH-NLs) against PA-induced oxidative injury was evaluated in terms of cell viability study, intracellular ROS, superoxide ions (O₂^-), MMP, and cellular GSH determination. Our results exhibited that NH-NLs significantly lessened the PA-induced hepatic oxidative injury in L02 cells via decreasing ROS and O₂^- generation, reducing MMP collapse, and attenuating GSH reduction, whereas the free NH samples were ineffective. Furthermore, the coated NH-NLs were more effective than that of uncoated nanoliposome. Overall, our study confirmed that P-CH-NH-NL was capable of reducing PA-induced hepatic oxidative injury. Therefore, the pectin-chitosan decorated nanoliposome can be considered as an efficient delivery system for enhancing cellular uptake of lipophilic compound with controlled release and greater biological activity.

Build-Up of a 3D Organogel Network within the Bilayer Shell of Nanoliposomes. A Novel Delivery System for Vitamin D3: Preparation, Characterization, and Physicochemical Stability

The inherent thermodynamic instability of liposomes during production and storage has limited their widespread applications. Therefore, a novel structure of food-grade nanoliposomes stabilized by a 3D organogel network within the bilayer shell was developed through the extrusion process and successfully applied to encapsulate vitamin D₃. A huge flocculation and a significant reduction of zeta potential (-17 mV) were observed in control nanoliposomes (without the organogel shell) after 2 months of storage at 4 °C, while the sample with a gelled bilayer showed excellent stability with a particle diameter of 105 nm and a high negative zeta potential (-63.4 mV), even after 3 months. The development of spherical vesicles was confirmed by TEM. Interestingly, the gelled bilayer shell led to improved stability against osmotically active divalent salt ions. Electron paramagnetic resonance confirmed the higher rigidity of the shell bilayer upon gelation. The novel liposome offered a dramatic increase in encapsulation efficiency and loading of vitamin D₃ compared to those of control.

A review on chemical and physical modifications of phytosterols and their influence on bioavailability and safety

Phytosterols have been shown to lower cholesterol levels and to have antioxidant, anti-inflammatory and other biological activities. However, the high melting point and poor solubility limit their bioavailability and practical application. It is advantageous to modify phytosterols chemically and physically. This article reviews and discusses the chemical and physical modifications of phytosterols, as well as their effects on the bioavailability and possible toxicity in vivo. The current research on chemical modifications is mainly focused on esterification to increase the oil solubility and water solubility. For physical modifications (mainly microencapsulation), there are biopolymer-based, surfactant-based and lipid-based nanocarriers. Both chemical and physical modifications of phytosterols can effectively increase the absorption and bioavailability. The safety of modified phytosterols is also an important issue. Phytosterol esters are generally considered to be safe. However, phytosterol oxides, which may be produced during the synthesis of phytosterol esters, have shown toxicity in animal models. The toxicity of nanocarriers also needs further studies.

Encapsulation of oyster protein hydrolysates in nanoliposomes: Vesicle characteristics, storage stability, in vitro release, and gastrointestinal digestion

In this study, oyster protein hydrolysates (OPH) were obtained from oyster meat by hydrolysis using animal complex proteases and then encapsulated in nanoliposomes. The physicochemical properties, stability, and digestive characteristics of OPH-loaded nanoliposomes were evaluated. The average size and zeta potential ranged from 95.64 to 102.39 nm and from -47.36 to -36.43 mV, respectively. Liposomes containing 4 mg/mL OPH had the highest encapsulation efficiency (74.53%). Fourier transform infrared spectroscopy analysis showed that effective ionic complexation and hydrogen bonding existed between phospholipid and peptides. The liposomes exhibited the highest stability when stored at 4 °C. Liposomal encapsulation may protect the antioxidant peptides in OPH during storage and simulated digestion. The nanoliposomes were not hydrolyzed and the structural integrity was maintained in gastric digestion, but exhibited lower stability in the intestinal phase. A prolonged release of OPH from nanoliposomes was also observed as compared with free OPH. Liposome containing protein hydrolysates may be used as a formula in functional foods. PRACTICAL APPLICATION: This study provides some useful information on the application of oyster protein hydrolysates or peptides in functional foods. The incorporation into liposomes may protect the hydrolysates against harsh conditions during storage and digestion, and also prolong the release time.

Galactosamine-modified PEG-PLA/TPGS micelles for the oral delivery of curcumin

In this study, galactosamine-modified poly(ethylene glycol)-poly(lactide) (Gal-PEG-PLA) polymers were synthesized and Gal-PEG-PLA/D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) micelles named as GPP micelles were designed to promote the oral absorption of a hydrophobic drug, curcumin (CUR). CUR-loaded Gal-PEG-PLA/TPGS micelles (CUR@GPP micelles) were fabricated using the thin-film dispersion method. CUR@GPP micelles had a size of about 100 nm, a near-neutral zeta potential, drug loading (DL) of 14.6%, and sustained release properties. GPP micelles with high Gal density (GPP3 micelles) were superior in facilitating uptake in epithelial cells and improving intestinal permeation. In situ intestinal absorption studies suggested that the jejunum and ileum were the best absorption segments in the intestinal tract. Additionally, biodistribution results revealed that GPP3 micelles could be remarkably taken up by the jejunum and ileum. Pharmacokinetics revealed that the maximum plasma concentration (C_max) and the area under the plasma concentration-time curve from 0 to 24 h (AUC_0-24) for CUR@GPP3 micelles were both significantly increased, and that the relative bioavailability of CUR@GPP3 micelles to CUR-loaded mPEG-PLA/TPGS micelles (CUR@PP micelles) was 258.8%. Furthermore, CUR-loaded micelles could reduce damage to the liver and intestinal tissues. This study highlights the importance of Gal content in the design of targeting nanocarrier Gal-modified micelles, which have broad prospects for oral delivery of hydrophobic drugs. Therefore, they could serve as a promising candidate for targeted delivery to the liver.

Novel γ-cyclodextrin-metal-organic frameworks for encapsulation of curcumin with improved loading capacity, physicochemical stability and controlled release properties

A safe and biodegradable γ-cyclodextrin-metal-organic-frameworks (γ-CD-MOFs) was successfully synthesized by using an improved hydrothermal method. In this study, curcumin (Cur) was chosen for testing the encapsulation stability and release performance of γ-CD-MOFs. Results of the crystal structure measurement indicated that the encapsulated curcumin within γ-CD-MOFs via van der Waals forces, hydrophobic interactions and hydrogen bonding was failed to disturb the inherent microtopography and crystallinity of γ-CD-MOFs. Compared to individual γ-CD, the γ-CD-MOFs exhibited improved loading capacity, physicochemical stability as well as controlled-release property in simulated digestion, and hence can be regarded as effective carriers for curcumin. Curcumin-loaded γ-CD-MOFs with a Cur : γ-CD-MOFs mass ratio of 2:3 (Cur-CD-MOFs/3), which showed the highest encapsulation efficiency (67.31 ± 2.25%), improved physicochemical stability and controlled-release performance, was selected for further research and industrialization. Our results demonstrate that γ-CD-MOFs can be regarded as a promising novel carrier for the delivery of curcumin or other hydrophobic nutraceuticals.

Amphiphilic polymeric nanoparticles encapsulating curcumin: Antioxidant, anti-inflammatory and biocompatibility studies

Oxidative stress and inflammation are two related processes common to many diseases. Curcumin is a natural compound with both antioxidant and anti-inflammatory properties, among others, that is recently being used as a natural occurring product alternative to traditional drugs. However, it has a hydrophobic nature that compromises its solubility in physiological fluids and its circulation time and also presents cytotoxicity problems in its free form, limiting the range of concentrations to be used. In order to overcome these drawbacks and taking advantage of the benefits of nanotechnology, the aim of this work is the development of curcumin loaded polymeric nanoparticles that can provide a controlled release of the drug and enlarge their application in the treatment of inflammatory and oxidative stress related diseases. Specifically, the vehicle is a bioactive terpolymer based on a α-tocopheryl methacrylate, 1-vinyl-2-pyrrolidone and N-vinylcaprolactam. Nanoparticles were obtained by nanoprecipitation and characterized in terms of size, morphology, stability, encapsulation efficiency and drug release. In vitro cellular assays were performed in human articular chondrocyte and RAW 264.7 cultures to assess cytotoxicity, cellular uptake, antioxidant and anti-inflammatory properties. The radical scavenging activity of the systems was confirmed by the DPPH test and the quantification of cellular reactive oxygen species. The anti-inflammatory potential of these systems was demonstrated by the reduction of different pro-inflammatory factors such as IL-8, MCP and MIP in chondrocytes; and nitric oxide, IL-6, TNF-α and MCP-1, among others, in RAW 264.7. Finally, the in vivo biocompatibility was confirmed in a rat model by subcutaneously injecting the nanoparticle dispersions. The reduction of curcumin toxicity and the antioxidant, anti-inflammatory and biocompatibility properties open the door to deeper in vitro and in vivo research on these curcumin loaded polymeric nanoparticles to treat inflammation and oxidative stress based diseases.

Nanostructured Pimpinella anisum essential oil as novel green food preservative against fungal infestation, aflatoxin B1 contamination and deterioration of nutritional qualities

Application of synthetic preservatives to control the contamination of stored food commodities with aflatoxin B₁ causing considerable loss in nutritional value is a major challenge. However, employment of essential oils for protecting food commodities is much limited due to high volatility, and increased susceptibility to oxidation. Therefore, objective of the present investigation was encapsulation of Pimpinella anisum essential oil in chitosan nanobiopolymer (CS-PAEO-Nm) to improve its bioefficacy, and sensorial suitability for application in food system. The synthesized CS-PAEO-Nm was characterized through SEM, FTIR, and XRD and evaluated for improved biological activity. The CS-PAEO-Nm exhibited improved antifungal (minimum inhibitory concentration = 0.08 μL/mL) and antiaflatoxigenic (minimum aflatoxin inhibitory concentration = 0.07 μL/mL) activities. CS-PAEO-Nm treatment significantly inhibited ergosterol, enhanced leakage of ions and induced impairment in defense enzymes (p < 0.05). In situ minerals and macronutrient preservation, and acceptable sensorial characteristics suggested possible recommendation of nanoencapsulated PAEO as potential safe green food preservative.

Stability and release performance of curcumin-loaded liposomes with varying content of hydrogenated phospholipids

The aim of this study was to substitute part of soybean phospholipid (SPC) with hydrogenated soybean phospholipid (HSPC) in curcumin-loaded liposomes (Cur-LP), in order to further enhance stability and release performances of curcumin. When the SPC/HSPC mass ratio changed from 10:0 to 5:5, vesicle size, encapsulation efficiency and alkali resistance of curcumin increased, although a small decrease in centrifugal stability was observed. Salt stability became worse as more HSPC was used (3:7 and 0:10). Owing storage at 4 °C and 25 °C, Cur-LP at a SPC/HSPC mass ratio of 5:5 performed well considering vesicle size, lipid oxidation and curcumin retention. These vesicles displayed also the best sustained-release performance in simulated digestion, attributed to the tighter lipid packing in membranes as indicated by fluorescence probes, DSC and FTIR. This study can guide the development of a Cur-LP product with improved shelf-life stability by using HSPC.

Enhanced exosome-mediated delivery of black bean phytochemicals (Phaseolus vulgaris L.) for cancer treatment applications

Exosomes are a subpopulation of membrane-derived cellular vesicles (30-150 nm) that play an important role in intercellular communication. Because of their natural function as nanocarriers, several applications have been developed for these nanovesicles, including drug delivery. Here we loaded saponins and flavonoids obtained from a black bean extract (Phaseolus vulgaris L.) with antiproliferative activity into exosomes extracted from different cell lines to induce an enhanced response in vitro. We demonstrated that exosomes can be loaded with at least three different phytochemicals in a one-step process to deliver these compounds to recipient cells. Moreover, we found that the bioactivity of the exosomal extract is greater than those observed in other formulations of the same extract. Our results suggest that exosomes are a promising alternative for improved delivery of complex mixtures of bioactive compounds, such as plant extracts. Therefore, future applications for these nanovesicles may include the development of new products for human use with enhanced nutraceutical properties.

Surface decoration of neohesperidin-loaded nanoliposome using chitosan and pectin for improving stability and controlled release

The aim of this study was to improve the physicochemical stability of neohesperidin (NH) using nanoliposomal encapsulation in association with surface decoration strategy employing chitosan (CH) and pectin (P). Different nanoliposomal systems, i.e. NH-loaded nanoliposome (NH-NL), CH-coated NH-NL (CH-NH-NL), and P-coated CH-NH-NL (P-CH-NH-NL) were characterized through DLS, HPLC, TEM, and FTIR. The results confirmed good encapsulation efficiency (>90%) and successful layer formation with nano-sized and spherical carrier. Both CH-NL and P-CH-NL exhibited better physicochemical stability than NL under storage, thermal, pH, ionic, UV, oxidative, and serum conditions. In vitro mucin adsorption study revealed that CH-NL (60%) was more effective in mucoadhesion followed by P-CH-NL (46%) and NL (41%). Furthermore, P-CH-NL showed better performance in NH retention under different food simulants compared to CH-NH-NL and NH-NL, in which the release was mainly governed by the diffusion process. Thus, the P-CH conjugated nanoliposome could be a promising nano-carrier for neohesperidin.

Preparation and evaluation of a Rubropunctatin-loaded liposome anticancer drug carrier

Rubropunctatin is a naturally occurring constituent of polyketide compounds that has great potential in the development of cancer-assisted chemotherapy. However, it has certain shortcomings such as water insolubility and photo instability that limit its clinical application. In this study, we constructed a Rubropunctatin-loaded liposome (R-Liposome) anticancer drug carrier for the first time. The results indicate that R-Liposome is water soluble, has spherical morphology, great homogeneity and dispersibility with high encapsulation efficiency (EE%, 90 ± 3.5%) and loading rate (LR%, 5.60 ± 2.5%) values. Moreover, the carrier improves the photostability, storage and pH stabilities of Rubropunctatin. The R-Liposome also prolongs the release of Rubropunctatin, enhances the anticancer activity of Rubropunctatin and encourages the mechanism of Rubropunctatin to promote apoptosis. Therefore, liposomal nanoparticles have great potential as drug delivery vehicles of Rubropunctatin for cancer treatment.

Mechanism and Improved Dissolution of Glycyrrhetinic Acid Solid Dispersion by Alkalizers

The purpose of this study was to increase the dissolution of glycyrrhetinic acid (GA) by preparing ternary solid dispersion (TSD) systems containing alkalizers, and to explore the modulating mechanism of alkalizers in solid dispersion systems. GA TSDs were prepared by hot melt extrusion (HME) with Kollidon^® VA64 as the carrier and L-arginine/meglumine as the alkalizers. The in vitro release of the TSD was investigated with a dissolution test, and the dissociation constant (pKa) was used to describe the ionization degree of the drug in different pH buffers. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD), Fourier Transform Infrared Spectroscopy (FTIR), Raman spectra, X-ray photoelectron spectroscopy (XPS), and a molecular model were used for solid-state characterizations and to study the dissolution mechanism of the TSDs. It was evident that the dissolution of GA significantly increased as a result of the TSD compared to the pure drug and binary solid dispersion. SEM, DSC, and XPRD data showed that GA transformed into an amorphous form in TSD. As illustrated by FTIR, Raman, XPS, and molecular docking, high binding energy ion-pair complexes formed between GA and the alkalizers during the process of HME. These can destroy the H-bond between GA molecules. Further, intermolecular H-bonds formed between the alkalizers and Kollidon^® VA64, which can increase the wettability of the drug. Our results will significantly improve the solubility and dissolution of GA. In addition, the lower pKa value of TSD indicates that higher ionization is beneficial to the dissolution of the drug. This study should facilitate further developments of TSDs containing alkalizers to improve the dissolution of weakly acidic drugs and gain a richer understanding of the mechanism of dissolution.