Environmental stress stability of microencapsules based on liposomes decorated with chitosan and sodium alginate

Curcumin-loaded proliposomes via glycerol-infused: Mechanism, stability and antioxidant activities

Liposome systems are highly advantageous for encapsulating curcumin with improved solubility and bioactivity. However, the conventional preparation of curcumin-loaded nanoliposomes is often hindered by the complex synthesis process, specialized equipment and the use of toxic organic solvents. This study presents a simple and green method for preparing curcumin-loaded nanoliposomes. Proliposomes were initially prepared by dissolving phospholipids in glycerol at a temperature exceeding the phase transition temperature (Tm) of the phospholipids. Differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR) analyses revealed that glycerol reduces the Tm value by disrupting hydrogen bonds with phospholipids. Curcumin was incorporated into the proliposomes through direct heating (15 mg/6 g proliposomes, stirred at 90 °C for 15 min), followed by hydration at room temperature to produce stable curcumin-loaded nanoliposomes. The resulting nanoliposomes exhibited high resilience to pH, ionic strength and heat treatment, with the encapsulation efficiency of 98.04 % for curcumin. During simulated digestion, the curcumin-loaded nanoliposomes exhibited exceptional gastrointestinal stability and increased the bioaccessibility of curcumin to 52.19 %. Compared to free curcumin, curcumin-loaded nanoliposomes mitigated oxidative stress in Lo-2 cells and displayed superior antioxidant activity. This study offers a green and efficient approach for synthesizing curcumin-loaded nanoliposomes and provides the novel insights on the nutrient delivery systems.

Fucoidan and chitosan electrostatically coated nanoliposomes enhance physicochemical stability and bioavailability of rutin

Rutin, a promising bioactive hydrophobic compound, suffers from poor physicochemical stability, resulting in low bioavailability. Herein, we used positively charged chitosan and negatively charged fucoidan as biopolymers coating rutin-nanoliposome (RNL) via electrostatic layer-by-layer self-assembly approach to prepare fucoidan/chitosan-coated rutin-nanoliposome (FC-RNL). The FC-RNL exhibited the encapsulation efficiency of 77.01% for rutin, with the particle size of 346 nm and a zeta potential of -33.5 mV under the optimized conditions (lecithin to rutin ratio of 10, 0.05 wt% fucoidan and 0.20 wt% chitosan). The results of Fourier transform infrared, X-ray diffraction, and transmission electron microscopy suggested that fucoidan/chitosan-coated nanoliposome could effectively load rutin. The coating of fucoidan and chitosan not only improved the retention rate of rutin (> 85 %) under thermal, oxidative and UV-light conditions, but also showed excellent stability over a wide pH range (pH 3.0-11.0) and high ionic strength (400 mM NaCl). In addition, FC-RNL was more stable than C-RNL and RNL at 4 °C for 5-week storage. In vitro simulated digestion indicated that FC-RNL significantly controlled the rutin release, and preserved 6.86 % and 50.47 % of rutin at the end of simulated gastric and intestinal digestion, respectively. Furthermore, FC-RNL exhibited satisfactory biocompatibility, and cellular uptake studies demonstrated that FC-RNL displayed the highest Rh123 uptake efficiency reaching approximately 189 %. This study provides an effective fucoidan/chitosan-coated nanoliposome carrier for the delivery of hydrophobic bioactive compounds within the functional food industry.

Preparation of sodium alginate and chitosan modified curcumin liposomes and study on the formation of protein corona

Curcumin (CUR) is a polyphenolic compound extracted from plants with a wide range of pharmacological activities. However, the low stability and bioavailability limits its practical application. This work utilized the chitosan (CH) and sodium alginate (SA) to modify the surface of the liposome to improve the stability of curcumin. Studies on the adsorption of pepsin to the surface of liposomes and the formation of protein coronas (PCs) were also carried out to investigate the in vivo behavior of the sodium alginate and chitosan modified curcumin liposomes (SA-CH-LPs). The result shown that the average particle size of SA-CH-LPs was around 220.7 ± 1.68 nm. X-ray Diffractometer (XRD) and differential scanning calorimeter (DSC) confirmed the successful preparation of SA-CH-LPs and illustrated their crystalline characteristics. The cytotoxicity of SA-CH-LPs was determined by CCK-8 assay and the results showed that the cell viability was above 80 % at different concentrations. In vitro results showed that the bioaccessibility of SA-CH-LPs (87.9 %) was better than curcumin liposomes (LPs) (66.4 %), and could better resist to catabolic degradation in the gastrointestinal environment. This work could provide the feasibility for improving the stability and bioaccessibility of the curcumin liposome, as well as given the preliminary evidence for investigation of the interaction with enzyme during the in vivo digestion process for the further application in food.

Nanolipsome Modified with Inulin and Pea Protein Isolate Improve the Thermal Stability and Slow the Release of Anthocyanin at Simulated In Vitro Digestion and Hot Cocoa Beverage

Anthocyanin (ACN) is a natural pigment with various biological activities, but their stability is compromised by external environmental factors, which limits their practical application in food processing. To enhance the stability of anthocyanin, double-layer-modified anthocyanin nanoliposomes (ACN-NLs) were prepared in this study using pea protein isolate (PPI) and inulin (IN) through layer-by-layer assembly in this study. The preparation conditions of unmodified, single-modified, and double-layer-modified nanoliposomes (ACN-NLs, PPI-ACN-NLs, and IN-PPI-ACN-NLs) were optimized via analysis of their average particle size, zeta potential, and encapsulation efficiency (EE). In addition, the structure of the nanoliposomes was characterized via transmission electron microscopy (TEM) and a Fourier transform infrared (FTIR) spectrometer. Furthermore, the thermal stability of nanoliposomes in hot cocoa and their release behavior during in vitro simulated digestion were evaluated. The results indicated that the optimal formulation for IN-PPI-ACN-NLs was 6% PPI and 2% IN. Under these conditions, the IN-PPI-ACN-NLs had a particle size of 270.2 ± 0.66 nm, a zeta potential of -15.76 ± 0.81 mV, and a high EE of 88.6 ± 0.71%. TEM analysis revealed that IN-PPI-ACN-NLs exhibited a spherical core-shell structure, while FTIR confirmed the interaction between ACNs and the encapsulating materials (PPI and IN). Compared with unmodified or monolayer-modified nanoliposomes, IN-PPI-ACN-NLs exhibited thermal stability in beverage systems and enhanced DPPH radical scavenging activity. During in vitro digestion, IN-PPI-ACN-NLs demonstrated a sustained-release effect and improved the digestive stability of ACN. These properties make it a promising functional additive for applications in the food and pharmaceutical industry.

Stability enhancement of proanthocyanidin-loaded liposomes via surface decoration with oxidized konjac glucomannan

The stability enhancement of proanthocyanidin-loaded liposomes (PC-Lip) via surface decoration with oxidized konjac glucomannan (OKGM) was investigated. The encapsulation efficiency and drug loading capacity of OKGM-coated PC-Lip (OKGM-PC-Lip) rose significantly. The average size and PDI of OKGM-PC-Lip increased, while the zeta potential decreased compared to those of PC-Lip. PC-Lip membrane fluidity reduced after coating with OKGM. The morphology of OKGM-PC-Lip showed that OKGM "halo layer" was formed on the liposome surface. Hydrogen bonding played an indispensable role in the combination between OKGM and PC-Lip, and the phase transition temperature of PC-Lip slightly increased after coating with OKGM. The retention rate of OKGM-PC-Lip was higher than that of PC-Lip at extreme pH. In vitro release, no significant difference in cumulative release was detected between OKGM-PC-Lip and PC-Lip at gastric stage, while the cumulative release rate of OKGM-PC-Lip was remarkably lower than that of PC-Lip at intestinal stage. The antioxidant activity of OKGM-PC-Lip was notably higher than that of PC-Lip. These results suggested that the resistance of PC-Lip to external influences was fruitfully enhanced after coating with OKGM. Compared with other polysaccharides, OKGM-coated liposomes may be more promising and advantageous in functional foods due to the polysaccharide's benefits to human health.

Engineering marine phospholipid nanoliposomes via glycerol-infused proliposomes: Mechanisms, strategies, and versatile applications in scalable food-grade nanoliposome production

This study presents a novel approach using polyol-based proliposome to produce marine phospholipids nanoliposomes. Proliposomes were formulated by blending glycerol with phospholipids across varying mass ratios (2:1 to 1:10) at room temperature. Analysis employing polarized light microscopy, FTIR, and DSC revealed that glycerol disrupted the stacked acyl groups within phospholipids, lowering the phase transition temperature (Tm). Krill oil phospholipids (KOP) proliposomes exhibited superior performance in nanoliposomes formation, with a mean diameter of 125.60 ± 3.97 nm, attributed to the decreased Tm (-7.64 and 7.00 °C) compared to soybean phospholipids, along with a correspondingly higher absolute zeta potential (-39.77 ± 1.18 mV). The resulting KOP proliposomes demonstrated liposomes formation stability over six months and under various environmental stresses (dilution, thermal, ionic strength, pH), coupled with in vitro absorption exceeding 90 %. This investigation elucidates the mechanism behind glycerol-formulated proliposomes and proposes innovative strategies for scalable, solvent-free nanoliposome production with implications for functional foods and pharmaceutical applications.

Ceftazidime and Usnic Acid Encapsulated in Chitosan-Coated Liposomes for Oral Administration against Colorectal Cancer-Inducing Escherichia coli

Escherichia coli has been associated with the induction of colorectal cancer (CRC). Thus, combined therapy incorporating usnic acid (UA) and antibiotics such as ceftazidime (CAZ), co-encapsulated in liposomes, could be an alternative. Coating the liposomes with chitosan (Chi) could facilitate the oral administration of this nanocarrier. Liposomes were prepared using the lipid film hydration method, followed by sonication and chitosan coating via the drip technique. Characterization included particle size, polydispersity index, zeta potential, pH, encapsulation efficiency, and physicochemical analyses. The minimum inhibitory concentration and minimum bactericidal concentration were determined against E. coli ATCC 25922, NCTC 13846, and H10407 using the microdilution method. Antibiofilm assays were conducted using the crystal violet method. The liposomes exhibited sizes ranging from 116.5 ± 5.3 to 240.3 ± 3.5 nm and zeta potentials between +16.4 ± 0.6 and +28 ± 0.8 mV. The encapsulation efficiencies were 51.5 ± 0.2% for CAZ and 99.94 ± 0.1% for UA. Lipo-CAZ-Chi and Lipo-UA-Chi exhibited antibacterial activity, inhibited biofilm formation, and preformed biofilms of E. coli. The Lipo-CAZ-UA-Chi and Lipo-CAZ-Chi + Lipo-UA-Chi formulations showed enhanced activities, potentially due to co-encapsulation or combination effects. These findings suggest potential for in vivo oral administration in future antibacterial and antibiofilm therapies against CRC-inducing bacteria.

Liposomes decorated with β-conglycinin and glycinin: Construction, structure and in vitro digestive stability

Liposomes were modified with different proportions of β-conglycinin (7S) and glycinin (11S) to form Lip-7S and Lip-11S. The morphology, interaction and in vitro simulated digestion of liposomes were studied. The particle size of Lip-7S was smaller than that of Lip-11S. When the values of Lip-7S and Lip-11S were 1:1 and 1:0.75, respectively, the ζ-potential had the maximum absolute value and the dispersion of the system was good. The results of multispectral analysis showed that hydrogen-bond and hydrophobic interaction dominated protein-modified liposomes, the protein structure adsorbed on the surface of liposomes changed, the content of α-helix decreased, and the structure of protein-modified liposomes became denser. The surface hydrophobicity and micropolarity of liposomes decreased with the increase of protein ratio, and tended to be stable after Lip-7S (1:1) and Lip-11S (1:0.75). Differential scanning calorimetry showed that Lip-7S had higher phase transition temperature (≥170.5 °C) and better rigid structure. During simulated digestion, Lip-7S (22.5 %) released less Morin than Lip (40.6 %) and Lip-11S (26.2 %), and effectively delayed the release of FFAs. The environmental stability of liposomes was effectively improved by protein modification, and 7S had better modification effect than 11S. This provides a theoretical basis for 7S and 11S modified liposomes, and also provides a data reference for searching for new materials for stabilization of liposomes.

Chondroitin sulfate and chitosan-coated liposomes as a novel delivery system for betanin: Preparation, characterization and in vitro digestion behavior

Betanin, a water-soluble pigment known for its high bioactivity, is hindered by pH and temperature sensitivity, weak ionic strength, and low bioavailability. In this study, nanoliposome (NPS), chitosan-coated NPS (CNPS), and chondroitin sulfate-chitosan bilayer-modified nanoliposomes (SCNPS) were prepared based on a layer-by-layer electrostatic interaction method for betanin encapsulation. The increase of polymer layers from NPS to SCNPS led to a monotonic increment from 223.57 to 522.33 nm in size, from -27.73 to 16.70 mV in negative charge and from 0.22 to 0.35 in polydispersity index. The chemical stability against pH (ranging from 2 to 10), ionic type (KCl, CaCl2, ALCl3) and ionic strength (100, 500 mM) significantly impacted the appearance and particle size of the double-layered nanoliposome. In vitro digestion experiment showed that SCNPS displayed higher stability and slower betanin release compared to NPS and CNPS. This study demonstrates that betanin can be efficiently encapsulated by SCNPS with improved stability and bioavailability.

Stability and cytotoxicity of biopolymer-coated liposomes for use in the oral cavity

This study investigates the stability and cytotoxicity of biopolymer-coated liposomes for use in the oral cavity. Liposomes (3 mM and 6 mM) were prepared by the thin film method and hydrated with phosphate buffer (PB) or glycerol phosphate buffer (G-PB). For coating, liposomes were added to a biopolymer solution of opposite charge. Particle stability was evaluated by measuring the size, polydispersity index, and zeta potential for up to 60 weeks. In vitro interaction of fluorescent-labelled biopolymer-coated liposomes and dysplastic oral keratinocytes was analyzed by confocal microscopy. Potential cytotoxicity was assessed in dysplastic oral keratinocytes by cell proliferation and cell viability. All three biopolymers showed good coating abilities for both concentrations and hydration media. The alginate coated liposomes in PB, 3 mM chitosan-coated liposomes in PB, and chitosan-coated liposomes in G-PB were stable for up to 60 weeks. In vitro studies demonstrated low cytotoxicity for all coated liposomes and non-specific cellular uptake of biopolymer-coated liposomes, independent of biopolymer, surface charge, lipid concentration and hydration media. All three formulations demonstrated low cytotoxicity and were considered safe. Alginate- and chitosan-coated liposomes demonstrated good stability over time and may be promising agents for use in the oral cavity and should be investigated further.

Encapsulation of Hydrophobic Apigenin into Small Unilamellar Liposomes Coated with Chitosan Through Ethanol Injection and Spray Drying

Despite the multiple health benefits, natural flavonoid apigenin has poor aqueous solubility that restricts its delivery in foods. This study investigated the potential of spray-dried chitosan-coated liposomes prepared from scalable methods for the food industry as the delivery carriers for apigenin. Apigenin-loaded small unilamellar liposomes produced from ethanol injection had an encapsulation efficiency of 74.88 ± 5.31%. They were electrostatically stabilised via chitosan coating (0.25% w/v) and spray-dried. Spray-dried chitosan-coated apigenin liposomes (SCAL) exhibited the following powder characteristics: yield 66.62 ± 3.08%, moisture content 4.33 ± 0.56%, water activity 0.2242 ± 0.0548, particle size 10.97 ± 1.55 μm, nearly spherical morphology with wrinkles and dents under microscopic observation. Compared with the unencapsulated apigenin, SCAL demonstrated improved aqueous solubility (10.22 ± 0.18 mg/L), higher antioxidant capacity, and stability against simulated gastrointestinal digestion. The chitosan coating gave a slower in-vitro release of apigenin in SCAL (77.0 ± 6.2%) than that of uncoated apigenin liposomes (94.0 ± 5.3%) at 12 h. The apigenin release kinetics from SCAL could be represented by the Korsmeyer-Peppas model (R2 = 0.971). These findings suggest that SCAL could be a promising delivery system of apigenin for functional food applications.

Improved membrane stability of alginate-chitosan microcapsules by crosslinking with tannic acid

OBJECTIVE

The insufficient stability of alginate-chitosan (ALG-CS) microcapsules in biorelevant media limits their applications in the biomedical field. Attempts were made to improve the membrane stability of ALG-CS microcapsules by noncovalent crosslinking with tannic acid.

RESULTS

The membrane stability of ALG-CS microcapsules in culture medium and serum was significantly improved by crosslinking with tannic acid. Moreover, the reason for the significant improvement in membrane stability had been demonstrated to be that the stability of chitosan-tannic acid (CS-TA) polyelectrolyte complexes was less affected by the competitive binding of those weak acid ions such as HCO₃^-. In addition, the optimal conditions for preparing alginate-chitosan-tannic acid (ALG-CS-TA) microcapsules were tannic acid concentration of 0.5% (w/v) and pH = 7.

CONCLUSION

The study provides a novel approach for improving the stability of the ALG-CS microcapsules in biorelevant media to expand their scope of application in the biological field.

Synthesis and characterization of fucoidan/chitosan-coated nanoliposomes for enhanced stability and oral bioavailability of hydrophilic catechin and hydrophobic juglone

This study aimed to improve the thermodynamic performance of nanoliposomes (NLs) using fucoidan (F) as the second-layer coating biopolymer along with chitosan (CS), to control the delivery and bioavailability of catechin (C) and juglone (J). The stabilized liposomal carrier of F/CS-conjugated JC-NL (F-CS-JC-NL) was developed with optimum concentrations of CS (0.09 wt%) and F (0.10 wt%), with the highest encapsulation efficiency of juglone (95.47%) and catechin (90.88%). Physicochemical characterization revealed that F-CS-JC-NL disclosed improved stability under different pH and ionic strengths, with the maximum juglone/catechin retention under thermal, oxidative and storage conditions. In vitro digestion revealed that NL double-coating (F-CS-JC-NL) significantly reduced compound leakage in the gastrointestinal tract, providing a controlled release and better bioavailability of juglone/catechin compared to CS-JC-NL and JC-NL. Conclusively, this study provides a novel NL-based delivery carrier with enhanced physicochemical stability and controlled release that might have promising use in delivering functional ingredients.

Preparation, characterization, and evaluation of flaxseed oil liposomes coated with chitosan and pea protein isolate hydrolysates

The effect of layer-by-layer coating of liposomes with chitosan and pea protein isolate hydrolysates (PPIH) was evaluated. Traditional flaxseed oil liposomes (FL Lipo) were used as a model for comparison to liposomes coated with chitosan and PPIH (FL LipoCP). The potential of PPIH as a coating material was evaluated. Additionally, the influence of chitosan and PPIH on vesicle size and zeta potential of liposomes was investigated. The chitosan layer of liposomes exhibited a loose structure. After the second layer of coating with PPIH, chitosan molecules were rearranged on the liposome surface, leading to a more compact and dense shell structure of liposomes. Electrostatic interactions, hydrogen bonds, and hydrophobic interactions favored the stability of FL LipoCP. Compared to FL Lipo, FL LipoCP displayed higher oxidation stability during storage and a slower release of flaxseed oil during in vitro digestion.

TPGS decorated NLC shift gefitinib from portal absorption into lymphatic delivery: Intracellular trafficking, biodistribution and bioavailability studies

Lymphatic drug delivery (LDD) is an attractive option for the prevention and treatment of cancer metastasis. This study aims to develop TPGS decorated nanostructure lipid carrier gefitinib loaded (TPGS-NLC-GEF). Biocompatibility and cytotoxicity were studied using erythrocytes and A549 cell lines. Furthermore, cellular uptake of the prepared TPGS-NLC was studied using 5-carboxyfluorescein (5-CF). Pharmacokinetic, biodistribution, and chylomicron-block flow studies were performed using male Wister Albino rats to investigate the influence of TPGS-NLC on plasma concentration-time profile, organ deposition, and LDD of GEF. The present results indicated that the prepared TPGS-NLC and TPGS-NLC-GEF formulation had a particle size range of 268 and 288 nm with a negative zeta-potential value of - 29.3 and - 26.5 mV, respectively. The in-vitro release showed burst drug release followed by sustained release. In addition, the biosafety in the term of the hemocompatibility study showed that the prepared formulation was safe at the therapeutic level. Additionally, an in-vitro cytotoxicity study showed that the TPGS-NLC was able to enhance the activity of GEF against the A549 cell line. The cellular uptake study showed the ability of TPGS-NLC to enhance 5-CF internalization by 12.6-fold compared to the 5-CF solution. Furthermore, the in-vivo study showed that TPGS-NLC was able to enhance GEF bioavailability (1.5-fold) through lymphatic system which was confirmed via the indirect chylomicron-block flow method. The tissue distribution study showed the ability of lipid nanoparticles to enhance lung drug deposition by 5.8-fold compared to a GEF suspension. This study concluded that GEF-NLC-GEF is an encouraging approach for the treatment of metastatic lung cancer through lymphatic delivery, enhanced bioavailability, and reduced systemic toxicity.

Improving shikonin solubility and stability by encapsulation in natural surfactant-coated shikonin nanoparticles

It is significant to develop a colloidal delivery system to improve the water solubility, stability, and bioavailability of shikonin, which is a hydrophobic plant polyphenol with a variety of physiological activities. In this study, three kinds of natural surfactants (saponin, sophorolipid, and rhamnolipid) were used to prepare shikonin nanoparticles by the pH-driven method. The physicochemical and structural properties of the shikonin nanoparticles were characterized, including particle size, zeta potential, and morphology. The encapsulation efficiencies of shikonin nanoparticles coated with saponin and sophorolipid were 97.6% and 97.3%, respectively, which were much higher than that of rhamnolipid-coated shikonin nanoparticles (19.0%). Shikonin nanoparticles coated with saponin and sophorolipid showed good resistance to heat and light and maintained long-term stability during storage. Moreover, shikonin nanoparticles coated with saponin and sophorolipid improved their in vitro-bioavailability. PRACTICAL APPLICATION: These article results are of great importance for improving the stability and bioavailability of shikonin in functional foods, dietary supplements, or pharmaceutical preparations. Moreover, this study provided theoretical and practical guides for further research of shikonin nanoparticles and may promote the development of natural colloidal delivery systems.

Modifying the Stability and Surface Characteristic of Anthocyanin Compounds Incorporated in the Nanoliposome by Chitosan Biopolymer

In this study, a novel approach was investigated to improve the stability of anthocyanin compounds (AC) by encapsulating them in nanoliposomes resulting from rapeseed lecithin alongside chitosan coating. The results indicate that the particle size, electrophoretic mobility, encapsulation efficiency, and membrane fluidity of nanoliposomes containing anthocyanin compounds were 132.41 nm, -3.26 µm·cm/V·S, 42.57%, and 3.41, respectively, which changed into 188.95 nm, +4.80 µm·cm/V·S, 61.15%, and 2.39 after coating with chitosan, respectively. The results also suggest improved physical and chemical stability of nanoliposomes after coating with chitosan. TEM images demonstrate the produced particles were spherical and had a nanoscale, where the existence of a chitosan layer around the nanoparticles was visible. Shear rheological tests illustrate that the flow behavior of nanoliposomes was altered from Newtonian to shear thinning following chitosan incorporation. Further, chitosan diminished the surface area of the hysteresis loop (thixotropic behavior). The oscillatory rheological tests also show the presence of chitosan led to the improved mechanical stability of nanoliposomes. The results of the present study demonstrate that chitosan coating remarkably improved encapsulation efficiency, as well as the physical and mechanical stability of nanoliposomes. Thus, coating AC-nanoliposomes with chitosan is a promising approach for effective loading of AC and enhancing their stability to apply in the pharmaceutic and food industries.

Alginate-Chitosan Coated Nanoliposomes as Effective Delivery Systems for Bamboo Leaf Flavonoids: Characterization, In Vitro Release, Skin Permeation and Anti-Senescence Activity

The use of bamboo leaf flavonoids (BLF) as functional food and cosmetic ingredients is limited by low bioavailability and difficulty in being absorbed by the intestine or skin. The aim of this study was to prepare BLF-loaded alginate-chitosan coated nanoliposomes (AL-CH-BLF-Lip) to overcome these challenges. The nanocarriers were characterized by dynamic light scattering, high performance liquid chromatography, Fourier transform infrared spectroscopy and differential scanning calorimetry. The biological activity was analyzed by in vitro antioxidant activity, transdermal absorption, cytotoxicity and AAPH induced HaCaT cell senescence model. The results showed that the size of nanocarriers ranged from 152.13 to 228.90 nm and had a low polydispersity index (0.25−0.36). Chitosan (CH) and alginate (AL) were successfully coated on BLF-loaded nanoliposomes (BLF-Lip), the encapsulation efficiency of BLF-Lip, BLF-loaded chitosan coated nanoliposomes (CH-BLF-Lip) and AL-CH-BLF-Lip were 71.31%, 78.77% and 82.74%, respectively. In addition, BLF-Lip, CH-BLF-Lip and AL-CH-BLF-Lip showed better in vitro release and free radical scavenging ability compared with naked BLF. In particular, the skin permeability of BLF-Lip, CH-BLF-Lip, and AL-CH-BLF-Lip increased 2.1, 2.4 and 2.9 times after 24 h, respectively. Furthermore, the use of nanoliposomes could significantly improve the anti-senescence activity of BLF (p < 0.01). Conclusively, alginate-chitosan coated nanoliposomes are promising delivery systems for BLF that can be used in functional foods and cosmetics.

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.

Construction of biopolymer-based nanoencapsulation of functional food ingredients using the pH-driven method: a review

Biopolymer-based nanoencapsulation presents great performance in the delivery of functional food ingredients. In recent years, the pH-driven method has received considerable attention due to its unique characteristics of low energy and organic solvent-free during the construction of biopolymer-based nanoencapsulation. This review summarized the fundamental knowledge of pH-driven biopolymer-based nanoencapsulation. The principle of the pH-driven method is the protonation reaction of functional food ingredients that change with pH. The stability of functional food ingredients in an alkaline environment is a prerequisite for the adoption of this method. pH regulator is also an important influencing factor. Different coating materials used to the pH-driven nanoencapsulation were discussed, including single and composite materials, mainly focusing on proteins. Besides, the application evaluations of pH-driven nanoencapsulation in food were analyzed. The future development trends will be the influence of pH regulators on the carrier, the design of new non-protein-based carriers, the quantification of driving forces, the absorption mechanism of encapsulated nutrients, and the molecular interaction between the wall material and the intestinal mucosa. In conclusion, pH-driven biopolymer-based nanoencapsulation of functional food ingredients will have broad prospects for development.

Chitosan-coated niosome as an efficient curcumin carrier to cross the blood-brain barrier: an animal study

This study aims to improve the curcumin bio-stability and brain permeability by loading in bare niosome (BN) and chitosan-coated niosome (ChN). Span 60, tween 60, and cholesterol were optimized as niosome shell components to attain the highest encapsulation efficiency (EE), besides the lowest particle size, using the mixture design method. The resulting optimized BN had a mean diameter of 80 ± 0.2 nm and surface charge of -31 ± 0.1 mv, which changed to 85 ± 0.15 nm and 35 ± 0.12 mv, respectively, after applying the chitosan layer. The EE% in bare niosome were about 80 ± 0.2, which changed to 82 ± 0.21 in ChN. The optimized formulation displayed sustained release, following the Hixson-Crowell model.Wistar rats were subjected to intraperitoneal injection (i.p.) of BN and ChN to evaluate the blood-brain barrier permeability of the curcumin. In this regard, ChN significantly increased curcumin concentration in different parts of the liver, plasma, and central nervous system (cerebral cortex, cerebellum, and stratum), compared with BN. Altogether, our results showed that ChN could be used as a promising delivery system for the treatment of some neurological diseases such as Alzheimer^'s.

Colonic Delivery of Celastrol-Loaded Layer-by-Layer Liposomes with Pectin/Trimethylated Chitosan Coating to Enhance Its Anti-Ulcerative Colitis Effects

Herein, a flexible oral colon-targeting delivery system, mediated by electrostatic layer-by-layer alternate deposition with pectin-trimethyl chitosan (TMC) onto liposomes-loading celastrol (Cel/PT-LbL Lipo), was fabricated to enhance anti-UC efficacy. Along with layer-by-layer coating, Cel/Lipo exhibited surface charge reversal, a slight increase in particle size, and a sustained drug release profile in a simulative gastrointestinal tract medium. Based on its bilayer coating of polysaccharides, Cel/PT-LbL Lipo alleviated cytotoxicity of celastrol in colon epithelial NCM460 cells. Due to the strong mucoadhesion of TMC with mucin, PT-LbL Lipo benefited colon localization and prolonged retention ability of its payloads. Ultimately, Cel/PT-LbL Lipo significantly mitigated colitis symptoms and accelerated colitis repair in DSS-treated mice by regulating the levels of pro-inflammatory factors related to the TLR4/MyD88/NF-κB signaling pathway. Collectively, this study demonstrates that the pectin/trimethylated chitosan coating may allow for Cel/PT-LbL Lipo to function as a more beneficial therapeutic strategy for UC treatment.

Curcumin Modulates 1,2-dibehenoyl-sn-glycero-3-phosphocholine (DBPC) Liposomes: Chitosan Oligosaccharide Lactate Influences Membrane Fluidity But Does Not Alter Phase Transition Temperature of DBPC Liposomes

1,2-dibehenoyl-sn-glycero-3-phosphocholine (DBPC) is one of the important phospholipids found in cell membrane but not studied well. Importance of curcumin as a dietary supplement and for its medicinal properites is getting widely recoginsed. The present study for the first time explores the effect of curcumin on properties of DBPC liposomes by monitoring the fluorescence properties of curcumin. The phase transition temperature (Tm) of DBPC is assessed which confirms increase in curcumin concentration causes a slight drop in the Tm value. Chitosan is being applied for various drug delivery uses. The study establishes new insight on effect of chitosan oligosaccharide lactate on DBPC liposomes. It is found that in the absence of chitosan oligosaccharide lactate, curcumin partitions more strongly in the liquids crystalline phase than in the solid gel phase, however, the opposite result is obtained with the presence of chitosan oligosaccharide lactate which penetrates into the DBPC liposomes membranes at higher temperature, blocking thus the passage of curcumin into the lipid bilayer. However, addition of chitosan oligosaccharide lactate had no effect on the Tm. Fluorescence quenching study of curcumin establishes that the location of curcumin to be in the hydrophobic cavity of DBPC membrane.

Coating of betanin and carvone Co-loaded nanoliposomes with synthesized cationic inulin: A strategy for enhancing the stability and bioavailability

Betanin (BET) and carvone (CAR) as antioxidant and antibacterial compounds were co-loaded in the coated nanoliposomes (NLPs) with cationic inulin to improve their stability and bioavailability. A cationic inulin was successfully synthesized and used for surface coating of the NLPs. The zeta potential, particle size, and PDI values of the coated NLPs were 21.70 ± 7.00 mV, 143.5 ± 15.2 nm, and 0.35 ± 0.03 respectively. The encapsulation efficiency values of the coated NLPs for BE and CAR were 86.1 ± 3.9 and 77.2 ± 5.2 %, respectively. Electron microscopy results showed that the coated NLPs had spherical and core-shell structures. The slowest sustained release profile in the simulated gastrointestinal condition was obtained for the coated NLPs. The physical and oxidative stability of NLPs, as well as the physical stability of loaded compounds were improved by surface coating. In conclusion, the developed nanocarrier is a suitable platform to use all benefits of BET and CAR in the food industry.

Selective antibacterial activities and storage stability of curcumin-loaded nanoliposomes prepared from bovine milk phospholipid and cholesterol

Present study prepared curcumin-loaded nanoliposomes using bovine milk, krill phospholipids and cholesterol; and investigated the effects of cholesterol on membrane characteristics, storage stability and antibacterial properties of the curcumin nanoliposomes. Bovine milk phospholipids which have higher saturation than krill phospholipids resulted in formation of curcumin-loaded nanoliposomes with higher encapsulation efficiency (84.78%), larger absolute value of zeta potential and vesicle size (size: 159.15 ± 5.27 nm, zeta potential: -28.3 ± 0.62 mV). Cholesterol helps to formation of a more hydrophobic, compact and tighter bilayer membrane structure which improved the storage stability of nanoliposomes under alkaline (66.25 ± 0.46%), heat (43.25 ± 0.69%) and sunlight (49.44 ± 1.78%) conditions. In addition, curcumin-loaded nanoliposomes can effectively target infectious bacteria which secrete pore-forming toxins such as Staphylococcus aureus by causing the bacterial cell wall to lysis. Findings from present work can guide future development of novel antibacterial agents for use in food preservation.

Microencapsulation: a pragmatic approach towards delivery of probiotics in gut

Probiotics confer numerous health benefits and functional foods prepared with these microbes own largest markets. However, their viability during transit from gastrointestinal tract is a concerning issue. Microencapsulation of probiotics is a novel technique of major interest to increase their survivability in GIT and food matrices by providing a physical barrier to protect them under harsh conditions. This article contributes the knowledge regarding microencapsulation by discussing probiotic foods, different methods and approaches of microencapsulation, coating materials, their release mechanisms at the target site, and interaction with probiotics, efficiency of encapsulated probiotics, their viability assessment methods, applications in food industry, and their future perspective. In our opinion, encapsulation has significantly got importance in the field of innovative probiotic enriched functional foods development to preserve their viability and long-term survival rate until product expiration date and their passage through gastro-intestinal tract. Previous review work has targeted some aspects of microencapsulation, this article highlights different methods of probiotics encapsulation and coating materials in relation with food matrices as well as challenges faced during applications: Gut microbiota; Lactic acid bacteria; Micro-encapsulation; Stability enhancement; Cell's release, Health benefits.

Characterization and Caco-2 Cell Transport Assay of Chito-Oligosaccharides Nano-Liposomes Based on Layer-by-Layer Coated

Chito-oligosaccharides (COSs) were encapsulated by the film-ultrasonic method into three nano-liposomes, which were uncoated liposomes (COSs-Lip), chitosan-coated liposomes (CH-COSs-Lip), and sodium alginate (SA)/chitosan (CH)-coated liposomes (SA/CH-COSs-Lip). The physicochemical and structural properties, as well as the stability and digestive characteristics, of all three nano-liposomes were assessed in the current study. Thereafter, the characteristics of intestinal absorption and transport of nano-liposomes were investigated by the Caco-2 cell monolayer. All nano-liposomes showed a smaller-sized distribution with a higher encapsulation efficiency. The ζ-potential, Z-average diameter (Dz), and polydispersity index (PDI) demonstrated that the stability of the SA/CH-COSs-Lip had much better stability than COSs-Lip and CH-COSs-Lip. In addition, the transport of the nano-liposomes via the Caco-2 cell monolayer indicated a higher transmembrane transport capacity. In summary, the chitosan and sodium alginate could serve as potential delivery systems for COSs to fortify functional foods and medicines.

Electrostatic deposition assisted preparation, characterization and evaluation of chrysin liposomes for breast cancer treatment

Chrysin (CHR), a flavone found in multiple vegetables, fruits and mushrooms has been explored so far as a neurotropic, anti-inflammatory and anti-cancer biomolecule. Despite the stated therapeutic potential, low solubility and bioavailability limit its therapeutic benefit. To circumvent these drawbacks, development of chrysin liposomes (CLPs) is reported in the present investigation. The CLPs were developed by electrostatic deposition assisted film hydration method using chitosan/lecithin to protect chrysin in the nano-lipoidal shell. Developed CLPs were extensively characterized by DSC, XPRD, FE-SEM, TEM, particle size, polydispersity index, zeta potential, percent drug loading and encapsulation efficiency. These CLPs were further characterized by in vitro dissolution, in vivo bioavailability, in vitro anticancer and stability study. Suitable particle size, PDI and ZP implying stabilization of developed CLPs. The % DL and % EE was found to be 3.56 ± 0.13 and 90.5 ± 1.49 respectively. DSC and PXRD study revealed amorphous transition of CHR, which may help to increase its solubility and dissolution profile. In vivo pharmacokinetic study demonstrated more than 5-fold increase in relative bioavailability of CLPs. The in silico molecular docking study results demonstrated the electrostatic interaction between two polymers. The present study suggests that chitosan could protect and encapsulate chrysin which eventually enhances its cytotoxicity as well as bioavailability.

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.

Enhancing stability and anti-inflammatory properties of curcumin in ulcerative colitis therapy using liposomes mediated colon-specific drug delivery system

Curcumin liposomes (CUR-LPs) was identified by evaluating morphology, appearance, zeta potential, particle diameter, and drug encapsulation efficiency. The results indicated that particle diameter, surface charge and polydispersity index (PDI) of curcumin (CUR)-loaded anionic liposomes were 167 nm, -34 mV and 0.09, respectively. CUR-LPs is high stable pseudo-pH-sensitive nanoparticles system which has a favorable stability in simulated gastric fluid and slower degradation rate allowing CUR sustained release for prolonged times in simulated intestinal fluid. Within 1 h, the CUR consumption was 21.82% in simulated gastric fluid (SGF) and 27.32% in simulated intestinal fluid (SIF), respectively. CUR-LPs could attenuate clinical symptoms including weight loss, diarrhea and fecal bleeding. Especially, it could also prevent dextran sulfate sodium salt (DSS)-inducedcolon tissue damage and colon shortening, and reduce the production of malondialdehyde (MDA), colonic myeloperoxidase (MPO), Interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in animal model. Our study illustrated that liposomes (LPs) was a potential carrier to develop the colon-specific drug delivery system incorporating CUR for treating ulcerative colitis.

Effect of heat treatment on the structure and stability of Grass pea (Lathyrus sativus) protein isolate/Alyssum homolocarpum seed gum nanoparticles

In the present study, Grass pea protein isolate (GPPI)- Alyssum homolocarpum seed gum (AHSG) complex nanoparticles were formed through two fabrication methods and their physicochemical properties, structure and stability against sodium chloride and different pHs were investigated. Type 1 particles were formed by creating GPPI nanoparticles, and then coating them with AHSG; while Type 2 particles were fabricated through the heat treatment of GPPI-AHSG complexes at 85 °C for 15 min. The preparation methods did not influence the magnitude of electrical charges on biopolymer particles. The particle size analysis revealed that Type 2 particles had lower mean diameter (d = 360.20 nm) compared to Type 1 particles (d = 463.22 nm). Structural properties of Type 1 and Type 2 particles were determined using Fourier transform infrared (FTIR) spectroscopy, X-ray diffractometry (XRD), Differential scanning calorimetry (DSC), Atomic force microscopy (AFM), and transmission electron microscopy (TEM). Hydrogen bonding, electrostatic and hydrophobic interactions were the main driving forces contributed to the formation of both GPPI-AHSG complex particles. Assessments of morphological and structural properties also indicated that both Type 1 and 2 particles had spherical shapes and heat treatment increased the ordered intermolecular structures in biopolymer particles. Type 2 particles had higher denaturation temperature and better pH and salt stability when compared to Type 1 particles. These results indicate that thermal treatment was effective for the fabrication of stable GPPI-AHSG complex nanoparticles.

Biopolymer-liposome hybrid systems for controlled delivery of bioactive compounds: Recent advances

Conventional liposomes still face many challenges associated with the poor physical and chemical stability, considerable loss of encapsulated cargo, lack of stimulus responsiveness, and rapid elimination from blood circulation. Integration of versatile functional biopolymers has emerged as an attractive strategy to overcome the limitation of usage of liposomes. This review comprehensively summarizes the most recent studies (2015-2020) and their challenges aiming at the exploration of biopolymer-liposome hybrid systems, including surface-modified liposomes, biopolymer-incorporated liposomes, guest-in-cyclodextrin-in-liposome, liposome-in-hydrogel, liposome-in-film, and liposome-in-nanofiber. The physicochemical principles and key technical information underlying the combined strategies for the fabrication of polymeric liposomes, the advantages and limitations of each of the systems, and the stabilization mechanisms are discussed through various case studies. Special emphasis is directed toward the synergistic efficiencies of biopolymers and phospholipid bilayers on encapsulation, protection, and controlled delivery of bioactives (e.g., vitamins, carotenoids, phenolics, peptides, and other health-related compounds) for the biomedical, pharmaceutical, cosmetic, and functional food applications. The major challenges, opportunities, and possible further developments for future studies are also highlighted.

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.

Chitosan-Coating Effect on the Characteristics of Liposomes: A Focus on Bioactive Compounds and Essential Oils: A Review

In recent years, liposomes have gained increasing attention for their potential applications as drug delivery systems in the pharmaceutic, cosmetic and food industries. However, they have a tendency to aggregate and are sensitive to degradation caused by several factors, which may limit their effectiveness. A promising approach to improve liposomal stability is to modify liposomal surfaces by forming polymeric layers. Among natural polymers, chitosan has received great interest due to its biocompatibility and biodegradability. This review discussed the characteristics of this combined system, called chitosomes, in comparison to those of conventional liposomes. The coating of liposomes with chitosan or its derivatives improved liposome stability, provided sustained drug release and increased drug penetration across mucus layers. The mechanisms behind these results are highlighted in this paper. Alternative assembly of polyelectrolytes using alginate, sodium hyaluronate, or pectin with chitosan could further improve the liposomal characteristics. Chitosomal encapsulation could also ensure targeted delivery and boost the antimicrobial efficacy of essential oils (EOs). Moreover, chitosomes could be an efficient tool to overcome the major drawbacks related to the chemical properties of EOs (low water solubility, sensitivity to oxygen, light, heat, and humidity) and their poor bioavailability. Overall, chitosomes could be considered as a promising strategy to enlarge the use of liposomes.

Development of microcapsules using chitosan and alginate via W/O emulsion for the protection of hydrophilic compounds by comparing with hydrogel beads

It is a critical challenge to protect hydrophilic compounds in food or pharmaceutical applications due to their strong tendency to leak out of the capsules into the external aqueous phase. In this work, we developed an encapsulation system that can protect hydrophilic ingredients using polyelectrolyte complexes prepared with chitosan and alginate via water-in-oil (W/O) emulsion. Unlike the traditional preparation of hydrogel beads, in which one material was added dropwise to another that had an opposite charge, we prepared microcapsules by electrostatic interaction between the positively charged -NH₃⁺ groups of chitosan and the negatively charged -COO^- groups of alginate by W/O emulsion via ultrasonication, which prevented the formation of large complexes. The preparation conditions were optimized at an ultrasonic power of 375 W and alginate/chitosan ratio of 7:5, in which the alginate/chitosan microcapsules presented a good polydispersity index of 0.26 and zeta potential of -44.6 mV. The SEM and TEM images showed the microcapsule contained multiple, irregular, conglutinated spheres with a core and shell structure. High encapsulation efficiency and retention efficiency showed its potential to protect hydrophilic components from harsh environments. This method provides a simple route that can efficiently encapsulate a wide range of food or pharmaceutical hydrophilic ingredients.