On improving bioaccessibility and targeted release of curcumin-whey protein complex microparticles in food

Delivery of encapsulated bioactive compounds within food matrices to the digestive tract: recent trends and future perspectives

Encapsulation technologies have achieved encouraging results improving the stability, bioaccessibility and absorption of bioactive compounds post-consumption. There is a bulk of published research on the gastrointestinal behavior of encapsulated bioactive food materials alone using in vitro and in vivo digestion models, but an aspect often overlooked is the impact of the food structure, which is much more complex to unravel and still not well understood. This review focuses on discussing the recent findings in the application of encapsulated bioactive components in fabricated food matrices. Studies have suggested that the integration of encapsulated bioactive compounds has been proven to have an impact on the physicochemical characteristics of the finished product in addition to the protective effect of encapsulation on the fortified bioactive compound. These products containing bioactive compounds undergo further structural reorganization during digestion, impacting the release and emptying rates of fortified bioactive compounds. Thus, by manipulation of various food structures and matrices, the release and delivery of these bioactive compounds can be altered. This knowledge provides new opportunities for designing specialized foods for specific populations.

Incorporation of curcumin-loaded solid lipid nanoparticles into yogurt: Tribo-rheological properties and dynamic in vitro digestion

The incorporation of nanostructures loaded with bioactive compounds into food matrices is a promising approach to develop new functional foods with improved nutritional, health profiles and good sensorial properties. The rheological and tribological properties of yogurt enriched with curcumin-loaded solid lipid nanoparticles (SLN) were evaluated. Also, the TCA solubility index, the bioaccessibility of curcumin and cell viability were assessed after dynamic in vitro digestion. The presence of SLN in yogurt did not affect its rheological properties; however, SLN addition increased the lubrication capability of yogurt. After in vitro digestion, yogurt with added SLN (yogurt_SLN) presented a lower TCA solubility index (22 %) than the plain yogurt (39 %). The bioaccessibility and stability of curcumin were statistically similar for yogurt_SLN (30 % and 42 %, respectively) and SLN alone (20 % and 39 %, respectively). Regarding cell viability results, the intestinal digesta filtrates of both controls (i.e., SLN alone and plain yogurt) did not affect significantly the cell viability, while the yogurt_SLN presented a possible cytotoxic effect at the concentrations tested. In general, the incorporation of SLN into yogurt seemed to promote the mouthfeel of the yogurt and did not adversely affect the bioaccessibility of curcumin. However, the interaction of SLN and yogurt matrix seemed to have a cytotoxic effect after in vitro digestion, which should be further investigated. Despite that, SLN has a high potential to be used as nanostructure in a functional food as a strategy to increase the bioactive compounds' bioaccessibility.

One-Pot Self-Assembly of Core-Shell Nanoparticles within Fibers by Coaxial Electrospinning for Intestine-Targeted Delivery of Curcumin

Nanotechniques for curcumin (Cur) encapsulation provided a potential capability to avoid limitations and improve biological activities in food and pharmaceutics. Different from multi-step encapsulation systems, in this study, zein-curcumin (Z-Cur) core-shell nanoparticles could be self-assembled within Eudragit S100 (ES100) fibers through one-pot coaxial electrospinning with Cur at an encapsulation efficiency (EE) of 96% for ES100-zein-Cur (ES100-Z-Cur) and EE of 67% for self-assembled Z-Cur. The resulting structure realized the double protection of Cur by ES100 and zein, which provided both pH responsiveness and sustained release performances. The self-assembled Z-Cur nanoparticles released from fibermats were spherical (diameter 328 nm) and had a relatively uniform distribution (polydispersity index 0.62). The spherical structures of Z-Cur nanoparticles and Z-Cur nanoparticles loaded in ES100 fibermats could be observed by transmission electron microscopy (TEM). Fourier transform infrared spectra (FTIR) and X-ray diffractometer (XRD) revealed that hydrophobic interactions occurred between the encapsulated Cur and zein, while Cur was amorphous (rather than in crystalline form). Loading in the fibermat could significantly enhance the photothermal stability of Cur. This novel one-pot system much more easily and efficiently combined nanoparticles and fibers together, offering inherent advantages such as step economy, operational simplicity, and synthetic efficiency. These core-shell biopolymer fibermats which incorporate Cur can be applied in pharmaceutical products toward the goals of sustainable and controllable intestine-targeted drug delivery.

Strategies for Improving Bioavailability, Bioactivity, and Physical-Chemical Behavior of Curcumin

Curcumin (CCM) is one of the most frequently explored plant compounds with various biological actions such as antibacterial, antiviral, antifungal, antineoplastic, and antioxidant/anti-inflammatory properties. The laboratory data and clinical trials have demonstrated that the bioavailability and bioactivity of curcumin are influenced by the feature of the curcumin molecular complex types. Curcumin has a high capacity to form molecular complexes with proteins (such as whey proteins, bovine serum albumin, β-lactoglobulin), carbohydrates, lipids, and natural compounds (e.g., resveratrol, piperine, quercetin). These complexes increase the bioactivity and bioavailability of curcumin. The current review provides these derivatization strategies for curcumin in terms of biological and physico-chemical aspects with a strong focus on different type of proteins, characterization methods, and thermodynamic features of protein–curcumin complexes, and with the aim of evaluating the best performances. The current literature review offers, taking into consideration various biological effects of the CCM, a whole approach for CCM-biomolecules interactions such as CCM-proteins, CCM-nanomaterials, and CCM-natural compounds regarding molecular strategies to improve the bioactivity as well as the bioavailability of curcumin in biological systems.

Digestion of curcumin-fortified yogurt in short/long gastric residence times using a near-real dynamic in vitro human stomach

A dynamic in vitro human stomach (DIVHS), simulating the anatomical structures, peristalsis, and biochemical environments of a real stomach as practically as possible, was applied to mimic the gastric pH and emptying during yogurt digestion in short/long gastric residence times. The influences of peristalsis, dilution, and proteolysis on digesta viscosity were quantified respectively, indicating the dominant role of proteolysis and dilution. After incorporating curcumin-whey protein microparticles with targeted-release formula in yogurt, the peak curcumin release during intestinal digestion reached 43% at 120 min in the short gastric residence time and 16% at 180 min in the long gastric residence time. The change in the maximum curcumin release depended on the gastric emptying kinetics in each residence time. This emptying-kinetics dependence was reflected by the slower microparticle disintegration and proteolysis in the long gastric residence time. The dynamic reproduction of realistic gastric conditions using DIVHS helps revealing controlled release from foods.

Effects of carboxymethyl cellulose/pectin coating combined with ultrasound pretreatment before drying on quality of turmeric (Curcuma longa L.)

Turmeric is an herb with multiple bioactive substances and health benefits. Drying is one of the most important steps of its processing and sales. In order to obtain high-quality turmeric products, we used five different pretreatment methods to treat turmeric prior to pulse-spouted microwave vacuum drying (PSMVD), including carboxymethyl cellulose coating (CMC), pectin coating (P), ultrasound (US) and their combination (CMCUS or PUS). The effect of different pretreatments on the drying kinetics, quality attributes and microstructure of turmeric were evaluated. Results showed that the US pretreatment had the shortest drying time (60 min), while coating treatment did not significantly affect drying rate. Dried turmeric with coating pretreatment had lower rehydration ratio and water adsorption capacity compared with individual ultrasound treatment. Carboxymethyl cellulose coating protected bioactive substances better than pectin coating. Moreover, CMCUS pretreatment showed significantly lower total color change, higher curcumin content, total phenols and flavonoid content as well as antioxidant capacity in all dried samples. Microstructure observation showed that the polysaccharide coating covering the surface of turmeric might reduce the degradation of bioactive compounds. Therefore, the CMCUS pretreatment before PSMVD of turmeric was recommended due to the efficiency and quality protections.

Sulphated glucuronomannan tetramer and hexamer from Sargassum thunbergii exhibit anti-human cytomegalovirus activity by blocking viral entry

Human cytomegalovirus (HCMV) remains a major public health burden worldwide. The anti-HCMV activity of glucuronomannan oligosaccharides (Gs) and sulphated glucuronomannan oligosaccharides (SGs) was investigated. Among these Gs and SGs, G4S1 and G6S1 (higher sulphated glucuronomannan tetramer and hexamer) showed satisfactory anti-HCMV activity starting at 50 μg/mL and 10 μg/mL, respectively. The results of the morphology, western blotting, qPCR and TCID50 assay showed that they prevented lytic cytopathic changes, inhibited the expression of IE1/2 and UL44, and reduced the UL123 copy number and virus titre significantly. It was interesting to note that degree of sulphation and polymerization was more important for anti-HCMV activity. Moreover, the anti-HCMV activities of G4S1 and G6S1 were stable when stored at 4 °C, -20 °C, and -80 °C for at least three months and mainly occurred in the early stage of HCMV infection through the negative charge of the sulphate groups and the interaction between SGs and the host cells.

Improving Curcumin Bioavailability: Current Strategies and Future Perspectives

Curcumin possesses a plethora of interesting pharmacological effects. Unfortunately, it is also characterized by problematic drug delivery and scarce bioavailability, representing the main problem related to the use of this compound. Poor absorption, fast metabolism, and rapid systemic clearance are the most important factors contributing to low curcumin levels in plasma and tissues. Accordingly, to overcome these issues, numerous strategies have been proposed and are investigated in this article. Due to advances in the drug delivery field, we describe here the most promising strategies for increasing curcumin bioavailability, including the use of adjuvant, complexed/encapsulated curcumin, specific curcumin formulations, and curcumin nanoparticles. We analyze current strategies, already available in the market, and the most advanced technologies that can offer a future perspective for effective curcumin formulations. We focus the attention on the effectiveness of curcumin-based formulations in clinical trials, providing a comprehensive summary. Clinical trial results, employing various delivery methods for curcumin, showed that improved bioavailability corresponds to increased therapeutic efficacy. Furthermore, advances in the field of nanoparticles hold great promise for developing curcumin-based complexes as effective therapeutic agents. Summarizing, suitable delivery methods for this polyphenol will ensure the possibility of using curcumin-derived formulations in clinical practice as preventive and disease-modifying therapeutics.