Chitosan-Based Anti-Oxidation Delivery Nano-Platform: Applications in the Encapsulation of DHA-Enriched Fish Oil

Drug Loading in Chitosan-Based Nanoparticles

Chitosan nanoparticles (CSNPs) are promising vehicles for targeted and controlled drug release. Recognized for their biodegradability, biocompatibility, low toxicity, and ease of production, CSNPs represent an effective approach to drug delivery. Encapsulating drugs within nanoparticles (NPs) provides numerous benefits compared to free drugs, such as increased bioavailability, minimized toxic side effects, improved delivery, and the incorporation of additional features like controlled release, imaging agents, targeted delivery, and combination therapies with multiple drugs. Keys parameters in nanomedicines are drug loading content and drug loading efficiency. Most current NP systems struggle with low drug loading, presenting a significant challenge to the field. This review summarizes recent research on developing CSNPs with high drug loading capacity, focusing on various synthesis strategies. It examines CSNP systems using different materials and drugs, providing details on their synthesis methods, drug loadings, encapsulation efficiencies, release profiles, stability, and applications in drug delivery. Additionally, the review discusses factors affecting drug loading, providing valuable guidelines for future CSNPs' development.

Microencapsulation of fish oil by spray drying, spray freeze-drying, freeze-drying, and microwave freeze-drying: Microcapsule characterization and storage stability

The objective of this paper was to evaluate the effect of spray drying (SD), spray freeze-drying (SFD), freeze-drying (FD), and microwave freeze-drying (MFD) on the characteristics of fish oil (FO) microcapsules. The physicochemical properties, morphology, fatty acid composition, and stability of the microcapsules were analyzed. The encapsulation efficiencies of microcapsules dried by SD, SFD, FD, and MFD were 86.98%, 77.79%, 63.29%, and 57.89%, respectively. SD microcapsules exhibited superior properties in terms of effective loading capacity, color, and flowability. Conversely, SFD microcapsules demonstrated improved solubility. Microencapsulation positively affected the thermal stability of FO, but the content of unsaturated fatty acids decreased. The findings from the storage experiment indicated that the oxidative stability of SD fish oil microcapsules was marginally lower compared to microcapsules produced through three alternative drying techniques, all of which were based on the FD concept. The comparison of various drying methods and their effects on the quality of FO microcapsules offers valuable insights that can serve as a foundation for the industrial production of high-quality microcapsules.

High oxidative stability of a complex fish liver oil nano-capsules in response to long-term storage, and to hyperthermal and sunlight exposure

BACKGROUND

In this study, a biocompatible nano-carrying platform using chitosan (ChI) and chondroitin sulfate (ChS) was developed for the encapsulation of cobia liver oil (CBLO) to prevent its oxidation and improve its absorption. An ionic gelation method was applied to encapsulate CBLO with different weight ratios (from 1.0 to 1.5) to obtain ChS-ChI nano-capsules (ChS-ChI@CBLO NCs).

RESULTS

Morphological observations of the nano-capsules revealed a spherical shape and diameter around 267-381 nm. The maximum loading capacity (LC) and encapsulation efficiency (EE) for ChS-ChI@CBLO NCs estimated by thermogravimetric analysis (TGA) and derivative thermogravimetric (DTG) analysis were 25.7% and 56.2%, respectively. The structural stability of ChS-ChI@CBLO NCs was confirmed through differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analysis; moreover DSC also further confirmed the oxidative stability of ChS-ChI@CBLO NCs. Fourier-transform infrared (FTIR) spectra confirmed the excellent stability of ChS-ChI@CBLO NCs against high temperature and sunlight exposure. Biocompatibility analysis also verified the non-toxicity of ChS-ChI@CBLO NCs, further indicating safety and potential application in complex-nutritional supplements.

CONCLUSION

Nano-degree of ChS-ChI@CBLO NCs has a loading capacity and encapsulation efficiency of around 16.5 ~ 25.7% and 33.4 ~ 56.2%, respectively, for encapsulation of CBLO. Characterization results also indicate that ChS-ChI@CBLO NCs display high oxidative stability against long-term, hyperthermal, and sunlight exposure. Bioassay results confirm that the ChS-ChI@CBLO NCs are safe and non-toxic. This study demonstrates that nano-capsules are also beneficial in preventing sensitive compounds from metamorphosis, and are non-toxic. These materials are suitable for use in the food and pharmaceutical industries. © 2023 Society of Chemical Industry.

Oxidized of chitosan with different molecular weights for potential antifungal and plant growth regulator applications

The application of Chitosan (CS) in drug delivery systems, plant growth promotion, antibacterial potentiality and plant defense is significantly limited by its inability to dissolve in neutral solutions. In this work, CS with different molecular weights (Mw) has been oxidized, yielding five kinds of oxidized chitosan (OCS 1-5) with solubilities in neutral solutions. The results obtained from Fourier Transform Infrared Spectroscopy clearly showed the successful oxidation of the hydroxyl group to form aldehyde and carboxyl groups. And the CS derivatives showed the wrinkled and lamellar structures on the surface of OCS. The results of antifungal activity against Fusarium graminearum showed that the OCS dissolved in 2 % (V/V) acetic acid exhibited better performance of almost complete inhibition of mycelial growth compared with CS at the concentration of 500 μg/mL. Among the five OCS, OCS-4 exhibited the best antifungal effect and had the lowest EC50 value of 581.68 μg/mL in samples. OCS-4 displayed superior promoting effect on seed germination with a germination potential of 62.2 % at a concentration of 3 g/L and a germination rate of 74.5 %. Additionally, the other four OCS also showed excellent antifungal activity with dose-dependent manners. These results indicated that the OCS had excellent antifungal potential in agricultural production.

Anti-obesity potential of a yogurt functionalized with a CLNA-rich pomegranate oil

Pomegranate oil is rich in conjugated linolenic acids, compounds which have attracted attention due to their potential applicability in obesity management as they are capable of modulating leptin and adiponectin secretion and regulate fatty acids storage and glucose metabolism. Among the possible bioactive foodstuffs capable of delivering these bioactive compounds yogurts have shown potential. Thus, the purpose of this work was to develop functional yogurts through the addition of pomegranate oil either in its free or encapsulated (used as a protective strategy against oxidation and gastrointestinal tract passage) forms. To that end, the pomegranate oil (free and encapsulated) was incorporated in yogurt and the functional yogurt capacity to modulate hepatic lipid accumulation, adipocyte metabolism (in terms of lipolysis, and adipokines secretion) and immune response was evaluated. The results obtained showed that the pomegranate oil's incorporation led to an improvement in the yogurts' nutritional values, with a reduction in its atherogenic and thrombogenic indexes (more than 78% for atherogenic and 76% for thrombogenic index) and an enhancement of its hypocholesterolemic/hypercholesterolemic ratio (more than 62%) when compared to the control yogurt. Furthermore, data also showed for the first time how these functional yogurts promoted modulation of metabolic processes post GIT as they were capable of reducing by 40% triglycerides accumulation in steatosis-induced Hep G2 cells and by 30 % in differentiated adipocytes. Moreover, samples also showed a capacity to modulate the leptin and adiponectin secretion (56 % of increase in adiponectin) and reduce the IL-6 secretion (ca 44%) and TNF-α (ca 12%) in LPS-stimulated cells. Thus, the CLNA-rich yogurt here developed showed potential as a viable nutraceutical alternative for obesity management.

Effect of Docosahexaenoic Acid Encapsulation with Whey Proteins on Rat Growth and Tissue Endocannabinoid Profile

Modifying the food structure allows a nutrient to be delivered differently, which can modify not only its digestion process but also its subsequent metabolism. In this study, rats received 3 g of omelette daily containing docosahexaenoic acid (DHA) as crude oil or previously encapsulated with whey proteins, whereas a control group received a DHA-free omelette. The results showed that DHA encapsulation markedly induced a different feeding behaviour so animals ate more and grew faster. Then, after four weeks, endocannabinoids and other N-acyl ethanolamides were quantified in plasma, brain, and heart. DHA supplementation strongly reduced endocannabinoid derivatives from omega-6 fatty acids. However, DHA encapsulation had no particular effect, other than a great increase in the content of DHA-derived docosahexaenoyl ethanolamide in the heart. While DHA supplementation has indeed shown an effect on cannabinoid profiles, its physiological effect appears to be mediated more through more efficient digestion of DHA oil droplets in the case of DHA encapsulation. Thus, the greater release of DHA and other dietary cannabinoids present may have activated the cannabinoid system differently, possibly more locally along the gastrointestinal tract. However, further studies are needed to evaluate the synergy between DHA encapsulation, fasting, hormones regulating food intake, and animal growth.

Encapsulation and antibacterial studies of goji berry and garlic extract in the biodegradable chitosan

As known, the chitosan is a biodegradable biopolymer with antibacterial properties, therefore it is used in the fields of pharmacy, medical, wastewater treatment, biotechnology, cosmetics, textiles, and agriculture. Apart from these, the chitosan has an important place in the food industry with its widespread use. In this research article, the chitosan were encapsulated with the taurine and garlic extracts by the spray dryer. The CSA and CSB compounds synthesized as final products were analyzed by Fourier transformed infrared spectroscopy (FTIR) and High Performance Liquid Chromatography (HPLC). The effect of the encapsulation process on the molecular weight of the polymer structure was investigated using the cryoscopy method. The compound CSA represents 1/2 encapsulation of chitosan with taurine and increased garlic extracts, respectively, while CSB represents 1/1 encapsulation of chitosan with increased taurine and fixed garlic extracts. The % antioxidant activity of the final products was determined by DDPH method. The inhibition zone and surface activity proporties of the CSA and CSB were carried out against Listeria monocytogenes, Staphylococcus aureus, E. coli, and Salmonella bacteria. The results obtained as a result of the analyzes were evaluated, and optimum values were determined for use in food packaging.

Amoxicillin-docosahexaenoic acid encapsulated chitosan-alginate nanoparticles as a delivery system with enhanced biocidal activities against Helicobacter pylori and improved ulcer healing

Encapsulation of amoxicillin (AMX) for drug delivery against Helicobacter pylori infection and aspirin-induced ulcers in rat's stomachs was performed using docosahexaenoic acid (DHA)-loaded chitosan/alginate (CA) nanoparticles (NPs) developed by ionotropic gelation method. The physicochemical analyses of the composite NPs were performed by scanning electron microscopy, Fourier transform infrared spectroscopy, zeta potential, X-ray diffraction, and atomic force microscopy. The encapsulation efficiency of AMX was increased to 76% by incorporating DHA, which resulted in a reduction in the particle size. The formed CA-DHA-AMX NPs effectively adhered to the bacteria and rat gastric mucosa. Their antibacterial properties were more potent than those of the single AMX and CA-DHA NPs as demonstrated by the in vivo assay. The composite NPs attained higher mucoadhesive potential during food intake than during fasting (p = 0.029). At 10 and 20 mg/kg AMX, the CA-AMX-DHA showed more potent activities against H. pylori than the CA-AMX, CA-DHA, and single AMX. The in vivo study showed that the effective dose of AMX was lower when DHA was included, indicating better drug delivery and stability of the encapsulated AMX. Both mucosal thickening and ulcer index were significantly higher in the groups receiving CA-DHA-AMX than in the groups receiving CA-AMX and single AMX. The presence of DHA declines the pro-inflammatory cytokines including IL-1β, IL-6, and IL-17A. The synergistic effects of AMX and the CA-DHA formulation increased the biocidal activities against H. pylori infection and improved ulcer healing properties.

Enzymatic Formation of Protectin Dx and Its Production by Whole-Cell Reaction Using Recombinant Lipoxygenases

In the human body, docosahexaenoic acid (DHA) contained in fish oil is converted to trace amounts of specialized pro-resolving mediators (SPMs) as the principal bioactive metabolites for their pharmacological effects. Protectin Dx (PDX), an SPM, is an important medicinal compound with biological activities such as modulation of endogenous antioxidant systems, inflammation pro-resolving action, and inhibition of influenza virus replication. Although it can be biotechnologically synthesized from DHA, it has not yet been produced quantitatively. Here, we found that 15S-lipoxygenase from Burkholderia thailandensis (BT 15SLOX) converted 10S-hydroxydocosahexaenoic acid (10S-HDHA) to PDX using enzymatic reactions, which was confirmed by LC-MS/MS and NMR analyses. Thus, whole-cell reactions of Escherichia coli cells expressing BT 15SLOX were performed in flasks to produce PDX from lipase-treated DHA-enriched fish oil along with E. coli cells expressing Mus musculus (mouse) 8S-lipoxygenase (MO 8SLOX) that converted DHA to 10S-HDHA. First, 1 mM DHA (DHA-enriched fish oil hydrolysate, DFOH) was obtained from 455 mg/L DHA-enriched fish oil by lipase for 1 h. Second, E. coli cells expressing MO 8SLOX converted 1 mM DHA in DFOH to 0.43 mM 10S-HDHA for 6 h. Finally, E. coli cells expressing BT 15SLOX converted 0.43 mM 10S-HDHA in MO 8SLOX-treated DFOH to 0.30 mM (108 mg/L) PDX for 5 h. Consequently, DHA-enriched fish oil at 455 mg/L was converted to 108 mg/L PDX after a total of 12 h (conversion yield: 24% (w/w); productivity: 4.5 mg/L/h). This study is the first report on the quantitative production of PDX via biotechnological approaches.