Development of novel biopolymer-based dendritic nanocomplexes for encapsulation of phenolic bioactive compounds: A proof-of-concept study

Apple pectin-based active films to preserve oil: Effects of naturally branched phytoglycogen-curcumin host

Pectin has excellent film-forming properties, but its functional properties need to be enhanced. Therefore, we constructed naturally branched phytoglycogen (PG) nanoparticles to solubilize curcumin (CCM) and further enhance the properties of apple pectin-based active films. The size of the PG spherical particles ranged from 30 to 100 nm with some aggregates. The branch density of the PG was 6.02 %. These PG nanoparticles increased the solubility of CCM nearly 1742-fold and a nanosized phytoglycogen-curcumin (PG-CCM) host was formed via hydrogen bonding and hydrophobic interaction. This host promoted the formation of pectin-based films with a dense structure and increased their tensile strength to 23.51 MPa. The coefficient to water vapor permeability, oxygen permeability and carbon dioxide permeability were all decreased indicating their barrier performance were improved. Among them, the oxygen permeability coefficient decreased most, from 1.14 × 10-7 g·m-1·s-1 to 0.8 × 10-7 g·m-1·s-1. Also, the transmittance of the active film at 280 nm and 660 nm decreased to 0.65 % and 72.10 %. Antioxidant and antibacterial properties were significantly enhanced (P < 0.05). And the results showed this film was an excellent oil packaging material. The active film incorporating PG-CCM host can replace heat-sealed plastic bags/pouch made from polyethylene and polypropylene synthetic plastics, and solve the problem that plastic packaging is difficult to degrade and cannot be squeezed clean. This provides a new conceptual framework for developing pectin-based active films by incorporating of PG and CCM.

Post pH-driven encapsulation of polyphenols in next-generation foods: principles, formation and applications

To meet the needs of a growing global population (∼10 billion by 2050), there is an urgent demand for sustainable, healthy, delicious, and affordable next-generation foods. Natural polyphenols, which are abundant in edible plants, have emerged as promising food additives due to their potential health benefits. However, incorporating polyphenols into food products presents various challenges, including issues related to crystallization, low water-solubility, limited bioavailability, and chemical instability. pH-driven or pH-shifting approaches have been proposed to incorporate polyphenols into the delivery systems. Nevertheless, it is unclear whether they can be generally used for the encapsulation of polyphenols into next-generation foods. Here, we highlight a post pH-driven (PPD) approach as a viable solution. The PPD approach inherits several advantages, such as simplicity, speed, and environmental friendliness, as it eliminates the need for heat, organic solvents, and complex equipment. Moreover, the PPD approach can be widely applied to different polyphenols and food systems, enhancing its versatility while also potentially contributing to reducing food waste. This review article aims to accelerate the implementation of the PPD approach in the development of polyphenol-fortified next-generation foods by providing a comprehensive understanding of its fundamental principles, encapsulation techniques, and potential applications in plant-based foods.

Dendrimers and Derivatives as Multifunctional Nanotherapeutics for Alzheimer's Disease

Alzheimer's disease (AD) is the most prevalent form of dementia. It affects more than 30 million people worldwide and costs over US$ 1.3 trillion annually. AD is characterized by the brain accumulation of amyloid β peptide in fibrillar structures and the accumulation of hyperphosphorylated tau aggregates in neurons, both leading to toxicity and neuronal death. At present, there are only seven drugs approved for the treatment of AD, of which only two can slow down cognitive decline. Moreover, their use is only recommended for the early stages of AD, meaning that the major portion of AD patients still have no disease-modifying treatment options. Therefore, there is an urgent need to develop efficient therapies for AD. In this context, nanobiomaterials, and dendrimers in particular, offer the possibility of developing multifunctional and multitargeted therapies. Due to their intrinsic characteristics, dendrimers are first-in-class macromolecules for drug delivery. They have a globular, well-defined, and hyperbranched structure, controllable nanosize and multivalency, which allows them to act as efficient and versatile nanocarriers of different therapeutic molecules. In addition, different types of dendrimers display antioxidant, anti-inflammatory, anti-bacterial, anti-viral, anti-prion, and most importantly for the AD field, anti-amyloidogenic properties. Therefore, dendrimers can not only be excellent nanocarriers, but also be used as drugs per se. Here, the outstanding properties of dendrimers and derivatives that make them excellent AD nanotherapeutics are reviewed and critically discussed. The biological properties of several dendritic structures (dendrimers, derivatives, and dendrimer-like polymers) that enable them to be used as drugs for AD treatment will be pointed out and the chemical and structural characteristics behind those properties will be analysed. The reported use of these nanomaterials as nanocarriers in AD preclinical research is also presented. Finally, future perspectives and challenges that need to be overcome to make their use in the clinic a reality are discussed.

Enzymatically hydrolyzed sodium caseinate nanoparticles efficiently enhancing the solubility, stability, and antioxidant and anti-biofilm activities of hydrophobic Tanshinone IIA

Enzymatic hydrolysis has been validated as an appropriate strategy for improving the properties of natural protein. Here, we used enzymatic hydrolysis sodium caseinate (Eh NaCas) as a nano-carrier for enhancing the solubility, stability, and antioxidant and anti-biofilm activities of hydrophobic encapsulants. Tanshinone IIA (TA) was loaded into the hydrophobic regions of Eh NaCas by self-assembly, and the encapsulation efficiency could reach 96.54 ± 0.14% under an optimized host-guest ratio. After Eh NaCas packed, the TA-loaded Eh NaCas nanoparticles (Eh NaCas@TA) showed regular spheres, uniform particle size distribution and more optimal drug release. Moreover, the solubility of TA in aqueous solution increased over 2.4 × 10⁵ times, and the TA guest molecules displayed excellent stability under light and other harsh environments. Interestingly, the vehicle protein and TA exhibited synergistic antioxidant effects. Furthermore, Eh NaCas@TA forcefully restrained the growth and destroyed the biofilm construction of Streptococcus mutans compared to free TA, showing positive antibacterial activity. The establishment of these results demonstrated the feasibility and functionality of edible protein hydrolysates as nano-carriers for loading natural plant hydrophobic extracts.

Eugenol nanoemulsion inactivates Listeria monocytogenes, Salmonella Enteritidis, and Escherichia coli O157:H7 on cantaloupes without affecting rind color

Listeria monocytogenes, Salmonella Enteritidis, and Escherichia coli O157:H7 are the major foodborne pathogens that have been implicated in outbreaks related to consumption of contaminated cantaloupes. Current chlorine-based decontamination strategies are not completely effective for inactivating the aforementioned pathogens on cantaloupes, especially in the presence of organic matter. This study investigated the efficacy of eugenol nanoemulsion (EGNE) wash treatments in inactivating L. monocytogenes, Salmonella spp., and E. coli O157:H7 on the surface of cantaloupes. In addition, the efficacy of EGNE in inhibiting the growth of the three pathogens on cantaloupes during refrigerated and room temperature storage of 5 days was investigated. Moreover, the effect of EGNE wash treatment on cantaloupe color was assessed using a Miniscan® XE Plus. The EGNE was prepared with either Tween 80 (TW) or a combination of Gum arabic and Lecithin (GA) as emulsifiers. The cantaloupe rind was washed with EGNE (0.3, 0.6, and 1.25%), in presence or absence of 5% organic load, for 1, 5, or 10 min at 25°C. Enumeration of surviving pathogens on cantaloupe was performed by serial dilution and plating on Oxford, XLD or SMA agar followed by incubation at 37°C for 24–48 h. EGNE-GA and EGNE-TW wash significantly reduced all three pathogens by at least 3.5 log CFU/cm2 as early as 5 min after treatment. EGNE-GA at 1.25% inactivated L. monocytogenes, E. coli O157:H7 and S. Enteritidis on cantaloupes to below the detectable limit within 5 and 10 min of treatment, respectively (~4 log CFU/cm2, P &lt; 0.05). EGNE treatments significantly reduced the survival of L. monocytogenes, S. Enteritidis, and E. coli O157:H7 on cantaloupe by at least 6 log CFU/cm2 at day 5 of storage at 25 and 4°C (P &lt; 0.05). Presence of organic matter did not modulate the antimicrobial efficacy of nanoemulsion treatments (P &gt; 0.05). EGNE treatments did not affect the rind color of cantaloupes (P &gt; 0.05). In conclusion, eugenol nanoemulsions could potentially be used as a natural sanitizer to inactivate foodborne pathogens on cantaloupes. Further investigations in an industry setting are warranted.

The anti-campylobacter activity of eugenol and its potential for poultry meat safety: A review

Poultry is one of the fastest growing industries due to advantages in land use, rapid production and advances in feed technology. The rising trend in the consumption of poultry meat over the last 50 years has also increased concerns about food safety. Campylobacter jejuniis the leading bacterial cause of gastroenteritis, the foremost cause of foodborne deaths. Despite significant progress in food safety methology, the genusCampylobacter remains a common foodborne pathogen in poultry. Increasing consumer demands for natural products require the discovery of new antimicrobials to ensure the safety of poultry meat. Recent studies have revealed that eugenol acts with antimicrobial activity on a wide variety of foodborne microorganisms. Eugenol is generally recognized as safe and is a promising preservative for the food industry. However, specific applications of eugenol need to be identified and validated to clarify the role of the food preservative in poultry meat safety.

Antimicrobial effects of thymol-loaded phytoglycogen/zein nanocomplexes against foodborne pathogens on fresh produce

In this study, thymol-loaded hydrophobically modified phytoglycogen/zein nanocomplexes with a particle size around 100 nm were developed for improving microbial safety of fresh produce. The antimicrobial activities, including the determination of minimum inhibitory and bactericidal concentration, growth kinetic curves, and inhibition zone of the nanocomplexes against foodborne pathogens (Listeria monocytogenes, Salmonella enteritidis, and Escherichia coli) were evaluated. The results showed that the antimicrobial activities of the nanocomplexes were significantly stronger than that of free thymol control (without encapsulation), and the antimicrobial efficacy remained unchanged after storage at 4 °C for 60 days. The morphological results from atomic force microscope revealed that small micellar blebs were formed at the surface of bacteria after treatment with nanocomplexes and the gradual disappearance of the cell boundary indicated the occurrence of cytolysis. The potential applications of this nanocomplex as disinfectant agent in wash water were evaluated on different types of fresh produce (lettuce, cantaloupe, and strawberries). Notably, the nanocomplexes also demonstrated efficacy in biofilm removal. Findings from this study clearly demonstrated that the thymol-loaded nanocomplexes hold promising potential for the disinfection of fresh produce to improve their microbial safety and quality.

Facile formation of injectable quaternized chitosan/tannic acid hydrogels with antibacterial and ROS scavenging capabilities for diabetic wound healing

The wound healing process of the diabetic wound is often hindered by excessive oxygen free radicals and infection. An ideal wound dressing should possess great reactive oxygen species (ROS) scavenging property and considerable antibacterial ability. In this study, we facilely constructed a novel hydrogel dressing with excellent ROS scavenging property and outstanding antibacterial performance by introducing tannic acid (TA) into quaternized chitosan (QCS) matrix. Attributing to the suitable physical crosslinking between TA and QCS, this QCS/TA hydrogel was endowed with injectable and self-healing properties, which could avoid the various external squeezing on the irregular shape by wound dressing. The results showed that it could promote coagulation, suppress inflammation and expedite collagen deposition in the skin defect model of diabetic rats. This study provides a facile and convenient method for constructing injectable hydrogel dressing, which has application potentials in the clinical management of diabetic wounds.

Encapsulation of phenolic compounds within food-grade carriers and delivery systems by pH-driven method: a systematic review

In comparison to conventional encapsulation methods of phenolic compounds (PCs), pH-driven method is green, simple and requires low energy consumption. It has a huge potential for industrial applications, and can overcome more effectively the aqueous solubility, stability and bioavailability issues related to PCs by changing pH to induce the encapsulation of PCs. This review aims to shed light on the use of pH-driven method for encapsulating PCs. The preparation steps and principles governing pH-driven method using various carriers and delivery systems are provided. A comparison of pH-driven with other methods is also presented. To circumvent the drawbacks of pH-driven method, improvement strategies are proposed. The essence of pH-driven method relies simultaneously on alkalization and acidification to bind PCs and carriers. It is used for the development of nanoemulsions, liposomes, edible films, nanoparticles, nanogels and functional foods. As a result of pH-driven method, PCs-loaded carriers may have smaller size, high encapsulation efficiency, more sustained-release and good bioavailability, due mainly to effects of pH change on the structure and properties of PCs as well as carriers. Finally, modification of wall materials and type of acidifier are considered as efficient approaches to improve the pH-driven method.