Efficient preparation of liposomes encapsulating food materials using lecithins by a mechanochemical method

Characterization of Nanohybridosomes from Lipids and Spruce Homogenate Containing Extracellular Vesicles

Introduction

Lipid nanovesicles associated with bioactive phytochemicals from spruce needle homogenate (here called nano-sized hybridosomes or nanohybridosomes, NSHs) were considered.

Methods

We formed NSHs by mixing appropriate amounts of lecithin, glycerol and supernatant of isolation of extracellular vesicles from spruce needle homogenate. We visualized NSHs by light microscopy and cryogenic transmission electron microscopy and assessed them by flow cytometry, dynamic light scattering, ultraviolet-visual spectroscopy, interferometric light microscopy and liquid chromatography-mass spectrometry.

Results

We found that the particles consisted of a bilayer membrane and a fluid-like interior. Flow cytometry and interferometric light microscopy measurements showed that the majority of the particles were nano-sized. Dynamic light scattering and interferometric light microscopy measurements agreed well on the average hydrodynamic radius of the particles Rh (between 140 and 180 nm), while the concentrations of the particles were in the range between 1013 and 1014/mL indicating that NSHs present a considerable (more than 25%) of the sample which is much more than the yield of natural extracellular vesicles (EVs) from spruce needle homogenate (estimated less than 1%). Spruce specific lipids and proteins were found in hybridosomes.

Discussion

Simple and low-cost preparation method, non-demanding saving process and efficient formation procedure suggest that large-scale production of NSHs from lipids and spruce needle homogenate is feasible.

Giant multilamellar and large unilamellar lecithin vesicles for the encapsulation and oral delivery of cannabinoids

The spontaneous formation of phospholipid vesicles was explored for the production of liposomal encapsulations of bioactive compounds. Low-energy processing methods were used to produce stable large unilamellar vesicles (LUVs) and giant multilamellar vesicles (GMVs) from unrefined, deoiled soybean and sunflower lecithin dispersions. The presence of these structures was confirmed by particle size analysis, bright-field and cryogenic transmission electron microscopy. Moreover, the liposomes were determined to be in a liquid crystalline state. Through molecular modelling, these liposomes were predicted to be capable of encapsulating cannabinoids within their membrane based on their structural and chemical similarity to cholesterol. The encapsulation capacities of cannabis oil in soybean and sunflower LUVs and spontaneous GMVs were then assessed based on these models. These liposomes demonstrated high thermal and oxidative stability, making them suitable for various food applications.

Characterizations and effects of pectin-coated nanoliposome loaded with Gijavash (Froriepia subpinnata) extract on the physicochemical properties of cheese

In this study, pectin-coated nanoliposomes containing Gijavash extract were used to formulate cheese and evaluate its shelf life, physicochemical, and sensory aspects. The study used a central composite design with three independent variables to prepare the cheese. The results showed that the optimal particle size, zeta potential, encapsulation efficiency, and DPPH radical antioxidant activity were 201.22 nm, -29.33 mV, 61.87%, and 57.54%, respectively. Adding nanoliposomes with varying extract amounts improved pH and lowered acidity in fortified cheeses. Moisture and lipolysis indices also improved after applying nanoliposomes. Sensory evaluation revealed that sensory acceptance was highest in the cheese with 15% extract. The study suggests that adding pectin-coated nanoliposomes containing Gijavash extract to cheese formulations may create novel products and improve their physicochemical properties.

A nano-Liposomal formulation potentiates antioxidant, anti-inflammatory, and fibrinolytic activities of Allolobophora caliginosa coelomic fluid: formulation and characterization

BACKGROUND

Coelomic fluid, a pharmacologically active compound in earthworms, exhibits a range of biological activities, including antioxidant, anti-inflammatory, and anticancer. However, the biological activities exerted by the coelomic fluid can be restrained by its low bioavailability and stability. Liposomes are progressively utilized as an entrapment system for natural bioactive compounds with poor bioavailability and stability, which could be appropriate for coelomic fluid. Thus, the present study was designed to fabricate, characterize, and evaluate the stability of liposomal formulation for Allolobophora caliginosa coelomic fluid (ACCF) as a natural antioxidant compound.

METHODS

The ACCF-liposomes were developed with a subsequent characterization of their physicochemical attributes. The physical stability, ACCF release behavior, and gastrointestinal stability were evaluated in vitro. The biological activities of ACCF and its liposomal formulation were also determined.

RESULTS

The liposomal formulation of ACCF had a steady characteristic absorption band at 201 nm and a transmittance of 99.20 ± 0.10%. Its average hydrodynamic particle size was 98 nm, with a PDI of 0.29 ± 0.04 and a negative zeta potential (-38.66 ± 0.33mV). TEM further confirmed the formation of vesicular, spherical nano-liposomes with unilamellar configuration. Additionally, a remarkable entrapment efficiency percent (77.58 ± 0.82%) with a permeability rate equal to 3.20 ± 0.31% and a high retention rate (54.16 ± 2.20%) for ACCF-liposomes were observed. The Fourier transform infrared spectroscopy (FTIR) result demonstrated that ACCF successfully entrapped inside liposomes. The ACCF-liposomes exhibited a slow and controlled ACCF release in vitro. Regarding stability studies, the liposomal formulation enhanced the stability of ACCF during storage and at different pH. Furthermore, ACCF-liposomes are highly stable in intestinal digestion conditions comparable to gastric digestion. The current study disclosed that liposomal formulation potentiates the biological activities of ACCF, especially antioxidant, anti-inflammatory, and thrombolytic activities.

CONCLUSION

These promising results offer a novel approach to increasing the bioaccessibility of ACCF, which may be crucial for the development of pharmaceuticals and nutraceutical-enriched functional foods.

Liposomes with Caffeic Acid: Morphological and Structural Characterisation, Their Properties and Stability in Time

Medical and pharmaceutical research has shown that liposomes are very efficient in transporting drugs to targets. In this study, we prepared six liposome formulas, three in which we entrapped caffeic acid (CA), and three with only phospholipids and without CA. Determination of entrapment efficiency (EE) showed that regardless of the phospholipids used, the percentage of CA entrapment was up to 76%. The characterization of the liposomes was performed using Dynamic Light Scattering (DLS), Atomic Force Microscopy (AFM), zeta potential and polydispersity and showed that about 75–99% of the liposomes had dimensions between 40 ± 0.55–500 ± 1.45 nm. The size and zeta potential of liposomes were influenced by the type of phospholipid used to obtain them. CA release from liposomes was performed using a six-cell Franz diffusion system, and it was observed that the release of entrapped CA occurs gradually, the highest amount occurring in the first eight hours (over 80%), after which the release is much reduced. Additionally, the time stability of the obtained liposomes was analysed using univariate and multivariate statistical analysis. Therefore, liposomes offer great potential in CA entrapment.

Formulation of chitosan coated nanoliposomes for the oral delivery of colistin sulfate: in vitro characterization, 99mTc-radiolabeling and in vivo biodistribution studies

Colistin sulfate is a very important antibiotic for the treatment of multidrug-resistant Gram-negative infections. Unfortunately, it has low oral bioavailability and several side effects following parenteral administration. The present study aims to develop chitosan-coated colistin nanoliposomes to improve the stability in the gastrointestinal tract and to enhance the oral delivery of colistin. The chitosan-coated colistin nanoliposomes were obtained via thin-film evaporation and electrostatic deposition methods using either Span 60, Tween 65 or Tween 80 as surfactants with different cholesterol: surfactant: soya lecithin ratios. The influence of systems variables was further characterized by vesicle size analysis, zeta potential (ZP), poly dispersibility index (PDI), and also their entrapment efficiency percentage (EE %) was evaluated. Various systems were formed with vesicle sizes in the nano-range, 155.64 ± 12.53 nm to 315.64 ± 15.90 nm, and EE % of 45.2 ± 2.9% to 81.8 ± 2.9%. Moreover, the ZP value of the prepared nanoliposomes switched from a negative to a positive value after chitosan coating. To track the released colistin in vivo, technetium 99m (^99mTc) was incorporated into the optimum system (S-3) system via direct coupling with colistin. Chitosan-coated ^99mTc-colistin nanoliposome, ^99mTc-colistin suspension, and ^99mTc-chitosan-coated nanoliposomes (placebo) were administered orally into bacterial infection (Escherichia coli) bearing mice. The biodistribution results showed that chitosan-coated nanoliposome significantly enhanced the bioavailability of colistin compared to colistin suspension (the commercially available). Moreover, the system effectively improved the localization of colistin at the infected muscle. In conclusion, this approach offers a promising tool for enhanced oral delivery of colistin.

Recent Advances in Nanotechnology with Nano-Phytochemicals: Molecular Mechanisms and Clinical Implications in Cancer Progression

Biocompatible nanoparticles (NPs) containing polymers, lipids (liposomes and micelles), dendrimers, ferritin, carbon nanotubes, quantum dots, ceramic, magnetic materials, and gold/silver have contributed to imaging diagnosis and targeted cancer therapy. However, only some NP drugs, including Doxil^® (liposome-encapsulated doxorubicin), Abraxane^® (albumin-bound paclitaxel), and Oncaspar^® (PEG-Asparaginase), have emerged on the pharmaceutical market to date. By contrast, several phytochemicals that were found to be effective in cultured cancer cells and animal studies have not shown significant efficacy in humans due to poor bioavailability and absorption, rapid clearance, resistance, and toxicity. Research to overcome these drawbacks by using phytochemical NPs remains in the early stages of clinical translation. Thus, in the current review, we discuss the progress in nanotechnology, research milestones, the molecular mechanisms of phytochemicals encapsulated in NPs, and clinical implications. Several challenges that must be overcome and future research perspectives are also described.

Comprehensive Survey on Nanobiomaterials for Bone Tissue Engineering Applications

One of the most important ideas ever produced by the application of materials science to the medical field is the notion of biomaterials. The nanostructured biomaterials play a crucial role in the development of new treatment strategies including not only the replacement of tissues and organs, but also repair and regeneration. They are designed to interact with damaged or injured tissues to induce regeneration, or as a forest for the production of laboratory tissues, so they must be micro-environmentally sensitive. The existing materials have many limitations, including impaired cell attachment, proliferation, and toxicity. Nanotechnology may open new avenues to bone tissue engineering by forming new assemblies similar in size and shape to the existing hierarchical bone structure. Organic and inorganic nanobiomaterials are increasingly used for bone tissue engineering applications because they may allow to overcome some of the current restrictions entailed by bone regeneration methods. This review covers the applications of different organic and inorganic nanobiomaterials in the field of hard tissue engineering.

Growth-Inhibitory Effect of Chitosan-Coated Liposomes Encapsulating Curcumin on MCF-7 Breast Cancer Cells

Current anticancer drugs exhibit limited efficacy and initiate severe side effects. As such, identifying bioactive anticancer agents that can surpass these limitations is a necessity. One such agent, curcumin, is a polyphenolic compound derived from turmeric, and has been widely investigated for its potential anti-inflammatory and anticancer effects over the last 40 years. However, the poor bioavailability of curcumin, caused by its low absorption, limits its clinical use. In order to solve this issue, in this study, curcumin was encapsulated in chitosan-coated nanoliposomes derived from three natural lecithin sources. Liposomal formulations were all in the nanometric scale (around 120 nm) and negatively charged (around -40 mV). Among the three lecithins, salmon lecithin presented the highest growth-inhibitory effect on MCF-7 cells (two times lower growth than the control group for 12 µM of curcumin and four times lower for 20 µM of curcumin). The soya and rapeseed lecithins showed a similar growth-inhibitory effect on the tumor cells. Moreover, coating nanoliposomes with chitosan enabled a higher loading efficiency of curcumin (88% for coated liposomes compared to 65% for the non-coated liposomes) and a stronger growth-inhibitory effect on MCF-7 breast cancer cells.

A hybrid 3D-printed aspirin-laden liposome composite scaffold for bone tissue engineering

Bone defects are some of the most difficult injuries to treat in clinical medicine. Evidence from cellular and animal studies suggests that aspirin exhibits protective effects on bone by promoting both the survival of osteoblast precursor stem cells and osteoblast differentiation. However, acquired resistance to aspirin and its cytotoxicity significantly limit its therapeutic application. Controlled release systems have been confirmed to promote the efficacy of certain drugs for bone regeneration. Additionally, the controlled release of a high dose of drug allows for lower dosing over an extended period. In this way, nano-liposomal encapsulation of aspirin can be used to reduce the cytotoxicity of the overall dose. Using a series of osteogenic experiments, this study found that an aspirin-laden liposome delivery system (Asp@Lipo) obviously promoted osteogenesis and immunomodulation of human mesenchymal stem cells (hMSCs). We also studied the in vitro capacity of polycaprolactone (PCL)-based bioactive composite (PCL-Asp@Lipo) scaffolds to facilitate cell proliferation and osteoblast differentiation. Compared to a common scaffold, ALP assays, immunofluorescence and calcium mineralisation studies revealed that the PCL-Asp@Lipo scaffolds enhanced the osteogenic differentiation of hMSCs. Subsequently, along with the cells, PCL and PCL-Asp@Lipo scaffolds were both implanted subcutaneously into nude mice for estimation of osteo-inductivity after 6 weeks, the PCL-Asp@Lipo composite scaffold exhibited more osteogenic activity than the bare PCL scaffold. This approach has potential applications in bone tissue repair and regenerative medicine.

Evaluation of Physicochemical and Antioxidant Properties of Yogurt Enriched by Olive Leaf Phenolics within Nanoliposomes

Olive leaf extract is a rich source of phenolic compounds and oleuropein which is well-known regarding its antioxidant and antimicrobial attributes. However, the mentioned phenolic compounds will lose their beneficial properties during storage and induce undesirable aftertaste in food products. In this study, olive leaf extract-bearing nanoliposomes were produced via the ethanol injection method and using phosphatidyl choline plus cholesterol as the reagents for the wall material. Later, the prepared nanocarriers were examined in regard to their zeta potential, stability, encapsulation efficiency, and particle size. Moreover, the prepared nanoliposome-loaded yogurt samples were examined considering syneresis, antioxidant activity, pH, acidity, color, and sensorial properties. The mean particle size of the fabricated nanoliposomes was in the range of 25-158 nm. Also, the entire formulation had a negative charge. The encapsulation efficiency was between 70.7 to 88.2%. Besides, the application of nanoliposomes in yogurt improved the antioxidant activity, and unlike the yogurt with nonencapsulated olive extract, no significant changes in color and sensorial attributes were observed and even the syneresis rate was minimized. To conclude, olive leaf phenolics can be entrapped within nanoliposomes with a considerable encapsulation efficiency for application in food products like yogurt to increase their nutritional value and public acceptance.

The Positive Role of Curcumin-Loaded Salmon Nanoliposomes on the Culture of Primary Cortical Neurons

Curcumin (diferuloylmethane) is a natural bioactive compound with many health-promoting benefits. However, its poor water solubility and bioavailability has limited curcumin’s biomedical application. In the present study, we encapsulated curcumin into liposomes, formed from natural sources (salmon lecithin), and characterized its encapsulation efficiency and release profile. The proposed natural carriers increased the solubility and the bioavailability of curcumin. In addition, various physico-chemical properties of the developed soft nanocarriers with and without curcumin were studied. Nanoliposome-encapsulated curcumin increased the viability and network formation in the culture of primary cortical neurons and decreased the rate of apoptosis.

Bioactive polymeric formulations for wound healing

Ricinoleic acid (RA) has potential to promote wound healing because of its analgesic and anti-inflammatory properties. This study investigates the synthesis and characterization of RA liposomes infused in a hydrogel for topical application. Lecithin liposomes containing RA were prepared and incorporated into a chitosan solution and were subsequently cross-linked with dialdehyde β-cyclodextrin (Di-β-CD). Chitosan/Di-β-CD concentrations and reaction temperatures were varied to alter gelation time, water content, and mechanical properties of the hydrogel in an effort to obtain a wide range of RA release profiles. Hydrogel cross-linking was confirmed by spectroscopy, and liposome and carrier hydrogel morphology via microscopy. Chitosan, Di-β-CD, and liposome concentrations within the formulation affected the extent of matrix swelling, mechanical strength, and pore and overall morphology. Higher cross-linking density of the hydrogel led to lower water uptake and slower release rate of RA. Optimized formulations resulted in a burst release of RA followed by a steady release pattern accounting for 80% of the encapsulated RA over a period of 48 hours. However, RA concentrations above 0.1 mg/mL were found to be cytotoxic to fibroblast cultures in vitro because of the oily nature of RA. These formulations promoted wound healing when used to treat full thickness skin wounds (2 cm²) in Wister male rats. The wound contraction rates were significantly higher compared to a commercially available topical cream after a time period of 21 days. Histopathological analysis of the RA-liposomal chitosan hydrogel group showed that the epidermis, dermis, and subcutaneous skin layers displayed an accelerated yet normal healing compared to control group.

Lipid nanoparticles assessment by flow cytometry

BACKGROUND

Liposomes are promising carriers for drugs and bioactive compounds. Size and structure are their crucial parameters. Thus, it is essential to assess individual vesicles as prepared. Currently available techniques fail to measure liposome's size and structure simultaneously, with a high throughput. To solve this problem, we have developed a novel, flow cytometric method quantifying liposomes.

METHODS

Firstly, the following fluorescent staining combinations were tested: DiD/TO, Rh123/DiD, Syto9/DiD. Further, chosen fluorochromes were used to compare three populations of vesicles: raw (R), obtained by thin film hydration and extruded ones (populations E10 and E21). Dynamic light scattering (DLS) was used for determination of average diameter and size distribution of nanocarriers. Structural differences between the raw and the extruded liposomes, as well as additional information concerning vesicles size were acquired employing atomic force microscopy (AFM).

RESULTS

DLS analysis indicated that, three distinct populations of vesicles were obtained. Liposomes were characterized by mean diameter of 323nm, 220nm and 170nm for population R, E10 and E21 respectively. All the populations were stable and revealed zeta potential of -29mV. AFM confirmed that raw and extruded liposomes were differed in structure.

CONCLUSIONS AND GENERAL SIGNIFICANCE

DiD/TO was the optimal fluorochrome combination that enabled to resolve distinctly the sub-populations of liposomes. Results obtained by flow cytometry were in a good agreement with those from DLS and AFM. It was proved that, flow cytometry, when proper fluorescent dyes are used, is an adequate method for liposomes assessment. The proposed method enables fast and reliable analysis of liposomes in their native environment.

Functional food microstructures for macronutrient release and delivery

There is a need to understand the role of fat, protein and carbohydrate in human health, and also how foods containing and/or structured using these macronutrients can be designed so that they can have a positive impact on health. This may include a reduction in fat, salt or sugar, the protection and targeted release of micronutrients or active ingredients from/to particular parts of the digestive system, improvement of gastrointestinal health or satiety enhancing properties. Such foods can be designed with various macro- and microstructures that will impact on macronutrient release and delivery. These include simple and double emulsions, the use of Pickering particles and shells, nanoparticles, liposomes, gelled networks, fluid gels and gel particles, foams, self-assembled structures, and encapsulated systems. In order to design foods that deliver these benefits understanding of how these structures behave in the gastrointestinal tract is also required, which should involve utilising both in vitro and in vivo studies. This review aims to draw together research in these areas, by focusing on the current state of the art, but also exciting possibilities for future research and food development.

Rice phytochemicals concentrated by molecular distillation process and their use as co-surfactant in water dispersion

This study investigated the effects of evaporating temperature during molecular distillation (MD) process employed to deodorizer distillate (DD) on the retention of rice phytochemicals in the unevaporated fraction (UMDs), which were then further used as co-surfactants in the fabrication of water-dispersible vesicles. The pilot-scale MD unit was operated at 120, 140 or 160 °C and 0.1 Pa to concentrate rice phytosterols from 1540.8 mg in 100 g DD to 3990.2-4904.8 mg in 100 g UMDs by evaporating out free fatty acids. Although γ-oryzanol content was increased from 598.9 mg in 100 g DD to 870.0-1018.1 mg in 100 g UMDs when the temperature was raised to 160 °C, such high temperature decreased tocols from 2185.7 mg in 100 g DD to 850.5 mg in 100 g UMDs and antioxidant capacity of UMDs measured as 2,2-diphenyl-1-picrylhydrazyl scavenging capacity. The UMD obtained after distillation at 140 °C was used as co-surfactant with soy lecithin, sucrose palmitate or polyoxyethylene sorbitan monooleate (Tween 80) to fabricate vesicles in pH 7.0 phosphate buffered saline (PBS). This study showed potential use of the UMD as a source of rice phytochemicals and a co-surfactant when used with Tween80 in small vesicle fabrication. The fabricated Tween 80/UMD vesicles in PBS had the size range of 200-300 nm and were stable within a temperature range of 4 to 37 °C for 96 h.

An efficient liposome based method for antioxidants encapsulation

Apigenin is an antioxidant that has shown a preventive activity against different cancer and cardiovascular disorders. In this study, we encapsulate apigenin with liposome to tackle the issue of its poor bioavailability and low stability. Apigenin loaded liposomes are fabricated with food-grade rapeseed lecithin in an aqueous medium in absence of any organic solvent. The liposome particle characteristics, such as particle size and polydispersity are optimised by tuning ultrasonic processing parameters. In addition, to measure the liposome encapsulation efficiency accurately, we establish a unique high-performance liquid chromatography technique in which an alkaline buffer mobile phase is used to prevent apigenin precipitation in the column;. salt is added to separate lipid particles from the aqeuous phase. Our results demonstrate that apigenin encapsulation efficiency is nearly 98% that is remarkably higher than any other reported value for encapsulation of this compound. In addition, the average particle size of these liposomes is 158.9 ± 6.1 nm that is suitable for the formulation of many food products, such as fortified fruit juice. The encapsulation method developed in this study, therefore have a high potential for the production of innovative, functional foods or nutraceutical products.

Liposome encapsulation of curcumin: physico-chemical characterizations and effects on MCF7 cancer cell proliferation

The role of curcumin (diferuloylmethane), for cancer treatment has been an area of growing interest. However, due to its low absorption, the poor bioavailability of curcumin limits its clinical use. In this study, we reported an approach of encapsulation a curcumin by nanoliposome to achieve an improved bioavailability of a poorly absorbed hydrophobic compound. We demonstrated that liposomal preparations to deliver curcumin increase its bioavailability. Liposomes composed of salmon's lecithin also improved curcumin bioavailability compared to those constituted of rapeseed and soya lecithins. A real-time label-free cell analysis system based on real-time cell impedance monitoring was used to investigate the in vitro cytotoxicity of liposomal preparations.

Cytotoxic effects of fucoidan nanoparticles against osteosarcoma

In this study, we analyzed the size-dependent bioactivities of fucoidan by comparing the cytotoxic effects of native fucoidan and fucoidan lipid nanoparticles on osteosarcoma in vitro and in vivo. In vitro experiments indicated that nanoparticle fucoidan induced apoptosis of an osteosarcoma cell line more efficiently than native fucoidan. The more potent effects of nanoparticle fucoidan, relative to native fucoidan, were confirmed in vivo using a xenograft osteosarcoma model. Caco-2 cell transport studies showed that permeation of nanoparticle fucoidan was higher than native fucoidan. The higher bioactivity and superior bioavailability of nanoparticle fucoidan could potentially be utilized to develop novel therapies for osteosarcoma.

Preparation and characterization of nanoliposomes entrapping medium-chain fatty acids and vitamin C by lyophilization

The complex nanoliposomes encapsulating both a hydrophilic drug vitamin C (vit C) and hydrophobic drug medium-chain fatty acids (MCFAs) was prepared by combining double emulsion method with dynamic high pressure microfluidization. The complex nanoliposomes was further freeze-dried under −86 °C for 48 h with sucrose at the sucrose/lipids ratio of 2:1(w/w) in order to enhance its stability. The freeze-dried complex nanoliposomes under the suitable conditions exhibited high entrapment efficiency of MCFAs (44.26 ± 3.34)%, relatively high entrapment efficiency of vit C (62.25 ± 3.43)%, low average size diameter (110.4 ± 7.28) nm and good storage stability at 4 °C for 60 days with slight changes in mean particle diameter and drug entrapment efficiencies. The results of transmission electron microscopy of freeze-dried complex nanoliposomes also showed that the freeze-dried samples with sucrose were stable without great increase in their particle sizes and without destroying their spherical shape. The results indicated that sucrose presented well protection effects in MCFAs-vit C complex nanoliposomes, suggesting the possibility of further usage in commercial liposomes.

Formulation and shelf life stability of water-borne lecithin nanoparticles for potential application in dietary supplements field

ABSTRACT The objective of the present investigation is to formulate commercial soybean lecithin as nanoparticles in solvent-free aqueous system for potential supplementary applications. A mechanical method, which involved two major steps, was used for that purpose. First, lecithin submicron particles (~ 0.5 μm) have been prepared by gradual hydration of lecithin powder using mechanical agitation. Finally, the size of these particles was further reduced to < 100 nm by using high-pressure microfluidization. The physical stability (appearance, particle size distribution, ζ-potential) and the chemical stability (lipid oxidation) of the dispersions carrying lecithin nanoparticles were assessed every 15 days during the 3-month shelf life period at two different temperatures. Results showed that the final particle size of lecithin in the freshly prepared aqueous dispersion was 79.8 ± 1.0 nm and the amount of peroxide detected was 3.5 ± 0.2 meq/kg lipid. At the end of the storage period, dispersions stored at 4°C exhibited physical and chemical stability as evident from the translucent appearance, the small change in particle size (84.1 ± 1.3 nm), and the small amount of generated peroxides (4.1 ± 0.2 meq/kg lipid). On the other hand, dispersions stored at 25°C were physically stable up to 60 days. Over that period, samples became turbid and the particle size increased to 145.0 ± 1.7 nm with a bimodal distribution pattern. This behavior was due to phospholipids (PLs) degradation and hydrolysis under acidic conditions, which proceeds faster at a relatively high temperature (25°C) than at (4°C). The outcome of this investigation may help in developing water-based dispersions carrying lecithin nanoparticles for dietary supplement of PLs.

Curcumin: an anti-inflammatory molecule from a curry spice on the path to cancer treatment

Oxidative damage and inflammation have been pointed out in preclinical studies as the root cause of cancer and other chronic diseases such as diabetes, hypertension, Alzheimer's disease, etc. Epidemiological and clinical studies have suggested that cancer could be prevented or significantly reduced by treatment with anti-oxidant and anti-inflammatory drugs, therefore, curcumin, a principal component of turmeric (a curry spice) showing strong anti-oxidant and anti-inflammatory activities, might be a potential candidate for the prevention and/or treatment of cancer and other chronic diseases. However, curcumin, a highly pleiotropic molecule with an excellent safety profile targeting multiple diseases with strong evidence on the molecular level, could not achieve its optimum therapeutic outcome in past clinical trials, largely due to its low solubility and poor bioavailability. Curcumin can be developed as a therapeutic drug through improvement in formulation properties or delivery systems, enabling its enhanced absorption and cellular uptake. This review mainly focuses on the anti-inflammatory potential of curcumin and recent developments in dosage form and nanoparticulate delivery systems with the possibilities of therapeutic application of curcumin for the prevention and/or treatment of cancer.

Conventional and dense gas techniques for the production of liposomes: a review

The aim of this review paper is to compare the potential of various techniques developed for production of homogenous, stable liposomes. Traditional techniques, such as Bangham, detergent depletion, ether/ethanol injection, reverse-phase evaporation and emulsion methods, were compared with the recent advanced techniques developed for liposome formation. The major hurdles for scaling up the traditional methods are the consumption of large quantities of volatile organic solvent, the stability and homogeneity of the liposomal product, as well as the lengthy multiple steps involved. The new methods have been designed to alleviate the current issues for liposome formulation. Dense gas liposome techniques are still in their infancy, however they have remarkable advantages in reducing the use of organic solvents, providing fast, single-stage production and producing stable, uniform liposomes. Techniques such as the membrane contactor and heating methods are also promising as they eliminate the use of organic solvent, however high temperature is still required for processing.