Utilization of Nanotechnology to Improve the Application and Bioavailability of Phytochemicals Derived from Waste Streams

Isolation of Extracellular Vesicles from Agri-Food Wastes: A Novel Perspective in the Valorization of Agri-Food Wastes and By-Products

Agri-food wastes generated by industrial food processing are valorized through the extraction of biomolecules to obtain value-added products useful for various industrial applications. In the present review, we describe the valuable by-products and bioactive molecules that can be obtained from agricultural wastes and propose extracellular vesicles (EVs) as innovative nutraceutical and therapeutic compounds that could be derived from agriculture residues. To support this idea, we described the general features and roles of EVs and focused on plant-derived extracellular vesicles (PDEVs) that are considered natural carriers of bioactive molecules and are involved in intercellular communication between diverse kingdoms of life. Consistently, PDEVs exert beneficial effects (anti-inflammatory, anti-tumor, and immune-modulatory) on mammalian cells. Although this research field is currently in its infancy, in the near future, the isolation of EVs and their use as nutraceutical tools could represent a new and innovative way to valorize waste from the agri-food industry in an ecofriendly way.

Application of inulin for the formulation and delivery of bioactive molecules and live cells

Inulin is a fructan biosynthesized mainly in plants of the Asteraceae family. It is also found in edible vegetables and fruits such as onion, garlic, leek, and banana. For the industrial production of inulin, chicory and Jerusalem artichoke are the main raw material. Inulin is used in the food, pharmaceutical, cosmetic as well biotechnological industries. It has a GRAS status and exhibits prebiotic properties. Inulin can be used as a wall material in the encapsulation process of drugs and other bioactive compounds and the development of their delivery systems. In the review, the use of inulin for the encapsulation of probiotics, essential and fatty oils, antioxidant compounds, natural colorant and other bioactive compounds is presented. The encapsulation techniques, materials and the properties of final products suitable for the delivery into food are discussed. Research limitations are also highlighted.

Resource-Efficient Use of Residues from Medicinal and Aromatic Plants for Production of Secondary Plant Metabolites

Although people's interest in green and healthy plant-based products and natural active ingredients in the cosmetic, pharmaceutical, and food industries is steadily increasing, medicinal and aromatic plants (MAPs) represent a niche crop type.It is possible to increase cultivation and sales of MAPs, by utilizing plant components that are usually discarded. This chapter provides an overview of studies concerning material flows and methods used for sustainable production of valuable metabolites from MAPs between 2018 and 2023. Additionally, it describes new developments and strategies for extraction and isolation, as well as innovative applications. In order to use these valuable resources almost completely, a systematic recycling of the plant material is recommended. This would be a profitable way to increase sustainability in the cultivation and usage of MAPs and provide new opportunities for extraction in plant science.

Enhancement of the bioavailability of phenolic compounds from fruit and vegetable waste by liposomal nanocarriers

Fruits and vegetables are one of the most consumed and processed commodities globally and comprise abundant phenolic compounds, one of the main nutraceuticals in the food industry. Comparably elevated rates of these compounds are found in waste (peel, seeds, leaf, stem, etc.) in the food processing industry. They are being investigated for their potential use in functional foods. However, phenolic compounds' low bioavailability limits their application, which can be approached by loading the phenolic compounds into an encapsulation system such as liposomal carriers. This review aims to elucidate the recent trend in extracting phenolic compounds from the waste stream and the means to load them in stable liposomes. Furthermore, the application of these liposomes with only natural extracts in food matrices is also presented. Many studies have indicated that liposomes can be a proper candidate for encapsulating and delivering phenolic compounds and as a means to increase their bioavailability.

Food-grade phytosome vesicles for nanoencapsulation of labile C-glucosylated xanthones and dihydrochalcones present in a plant extract matrix-Effect of process conditions and stability assessment

Phytosomes consist of a phytochemical bound to the hydrophilic choline head of a phospholipid. Their use in food products is gaining interest. However, literature on the use of food-grade solvents, crude plant extracts as opposed to pure compounds, and unrefined phospholipids to prepare phytosomes is limited. Furthermore, studies on compound stability are lacking. This study aimed to develop nano-phytosome vesicles prepared from inexpensive food-grade ingredients to improve the stability of polyphenolic compounds. Cyclopia subternata extract (CSE) was selected as a source of phenolic compounds. It contains substantial quantities of C-glucosyl xanthones, benzophenones, and dihydrochalcones, compounds largely neglected to date. The effect of process conditions on the complexation of CSE polyphenols with minimally refined food-grade fat-free soybean lecithin (PC) was studied. The PC:CSE ratio, sonication time, and reaction temperature were varied. This resulted in phytosomes ranging in vesicle size (113.7-312.7 nm), polydispersity index (0.31-0.48), and zeta potential (-55.0 to -38.9 mV). Variation was also observed in the yield (93.5%-96.0%), encapsulation efficiency (3.7%-79.0%), and loading capacity (LC, 1.3%-14.7%). Vesicle size and LC could be tailored by adjusting the sonication time and PC:CSE ratio, respectively. Chemical interaction between the lipid and the phenolic compounds was confirmed with nuclear magnetic resonance. Phytosomal formulation protected the compounds against degradation when freeze-dried samples were stored at 25 and 40°C for 6 months at low relative humidity. The study provided valuable information on the importance of specific process parameters in producing food-grade phytosomes with improved phenolic stability.

Next-generation meat preservation: integrating nano-natural substances to tackle hurdles and opportunities

The increasing global meat demand raises concerns regarding the spoilage of meat caused by microbial invasion and oxidative decomposition. Natural substances, as a gift from nature to humanity, possess broad-spectrum bioactivity and have been utilized for meat preservation. However, their limited stability, solubility, and availability hinder their further development. To address this predicament, advanced organic nanocarriers provide an effective shelter for the formation of nano-natural substances (NNS). This review comprehensively presents various natural substances derived from plants, animals, and microorganisms, along with the challenges they face. Subsequently, the potential of organic nanocarriers is explored, highlighting their distinct features and applicability, in addressing these challenges. The review methodically examines the application of NNS in meat preservation, with a focus on their pathways of action and preservation mechanisms. Furthermore, the outlook and future trends for NNS applications in meat preservation are concluded. The theory and practice summary of NNS is expected to serve as a catalyst for advancements that enhance meat security, promote human health, and contribute to sustainable development.

Structural characterization and stability of glycated bovine serum albumin-kaempferol nanocomplexes

Kaempferol (Kae), a flavonoid is endowed with various functions. However, due to its poor water solubility and stability, its application in the food and pharmaceutical fields remains elusive. Emerging reports have emphasized the importance of bovine serum albumin (BSA), and glycosylated BSA (GBSA) prepared in the nature deep eutectic solvent system as drug delivery system carriers. In our study, ultraviolet and fluorescence spectra revealed the higher interactions of BSA and GBSA with Kae. Through analysis of Z-average diameter, zeta-potential, polydispersity index (PDI), encapsulation efficiency (EE), loading capacity (LC) of BSA-Kae nanocomplexes (NPs) and GBSA-Kae NPs, GBSA-Kae NPs showed a higher absolute value of zeta-potential and lower PDI, while its EE and LC were also higher. Structural characterization and stability analysis revealed that GBSA-Kae NPs had more stable properties. This study laid the theoretical foundation for improving the solubility and stability of Kae during its delivery and transport.

Microbial Lipid Based Biorefinery Concepts: A Review of Status and Prospects

The use of lignocellulosic biomass as a raw material for the production of lipids has gained increasing attention, especially in recent years when the use of food in the production of biofuels has become a current technology. Thus, the competition for raw materials for both uses has brought the need to create technological alternatives to reduce this competition that could generate a reduction in the volume of food offered and a consequent commercial increase in the value of food. Furthermore, the use of microbial oils has been studied in many industrial branches, from the generation of renewable energy to the obtainment of several value-added products in the pharmaceutical and food industries. Thus, this review provides an overview of the feasibility and challenges observed in the production of microbial lipids through the use of lignocellulosic biomass in a biorefinery. Topics covered include biorefining technology, the microbial oil market, oily microorganisms, mechanisms involved in lipid-producing microbial metabolism, strain development, processes, lignocellulosic lipids, technical drawbacks, and lipid recovery.

Complexation between the Antioxidant Pterostilbene and Derivatized Cyclodextrins in the Solid State and in Aqueous Solution

Inadequate aqueous solubilities of bioactive compounds hinder their ability to be developed for medicinal applications. The potent antioxidant pterostilbene (PTB) is a case in point. The aim of this study was to use a series of modified water-soluble cyclodextrins (CDs), namely, hydroxypropyl β-CD (HPβCD), dimethylated β-CD (DIMEB), randomly methylated β-CD (RAMEB), and sulfobutyl ether β-CD sodium salt (SBECD) to prepare inclusion complexes of PTB via various solid, semi-solid, and solution-based treatments. Putative CD–PTB products generated by solid-state co-grinding, kneading, irradiation with microwaves, and the evaporative treatment of CD–PTB solutions were considered to have potential for future applications. Primary analytical methods for examining CD–PTB products included differential scanning calorimetry and Fourier transform infrared spectroscopy to detect the occurrence of binary complex formation. Phase solubility analysis was used to probe CD–PTB complexation in an aqueous solution. Complexation was evident in both the solid-state and in solution. Complex association constants (K1:1) in an aqueous solution spanned the approximate range of 15,000 to 55,000 M−1; the values increased with the CDs in the order HPβCD < DIMEB < RAMEB < SBECD. Significant PTB solubility enhancement factors were recorded at 100 mM CD concentrations, the most accurately determined values being in the range 700-fold to 1250-fold.

In Vitro-In Vivo Study of the Impact of Excipient Emulsions on the Bioavailability and Antioxidant Activity of Flavonoids: Influence of the Carrier Oil Type

The influence of the carrier oil type on the bioavailability and bioactivity of flavonoids (quercetin, kaempferol, and apigenin) was examined using in vitro digestion, in situ intestinal perfusion, and pharmacokinetic studies. Here, medium-chain triglycerides (MCTs), long-chain triglycerides (LCTs), or MCT/LCT mixtures (1:1, w/w) served as the oil phase of excipient emulsions. Overall, the bioavailability and antioxidant activity of flavonoids increased when they were coingested with excipient emulsions. The in vitro bioaccessibility of flavonoids was affected by the carrier oil: LCT (17.9-22.8%) > MCT/LCT (12.1-13.7%) > MCT (9.2-12.6%). These differences were mainly attributed to the fact that the mixed micelles formed after the digestion of LCTs had larger hydrophobic domains to solubilize more flavonoids. However, in vivo pharmacokinetic experiments showed that the flavonoid concentrations in rat serum were comparable for all carrier oils (p > 0.05). Our results assist in formulating excipient emulsions to enhance the efficacy of flavonoids.

Edible films/coatings containing bioactive ingredients with micro/nano encapsulation: A comprehensive review of their fabrications, formulas, multifunctionality and applications in food packaging

Due to the consumer's pursuit of safe, nontoxic and nutritious foods, edible and/or biodegradable materials have stood out in food packaging and preservation. In this context, the preparation and application of micro/nano encapsulated active ingredients (M/N-E-BAIs) represent a step toward reinforcing the properties of sustainable and controllable food packaging, particularly for the successful incorporation of new substances and functionalities into traditional edible films/coatings. This review, from the preparation of M/N-E-BAIs, the fabrication of edible film/coating containing M/N-E-BAIs to their characterization of multifunction and the application in food, makes a systematic summary and in-depth discussion. Food-grade polymers can encapsulate bioactive ingredients (BAIs) by chemical, physicochemical and mechanical methods, thereby forming M/N-E-BAIs with suitable sustained-release and unique biological activities. Furthermore, M/N-E-BAIs is incorporated into biopolymer substrates by solvent casting, 3D printing or electrostatic spinning to obtain novel edible films/coatings. This advanced packaging material exhibits superior physicochemical and functional properties over traditional food films/coatings. Besides, their applications in foods as active and intelligent packaging can improve food quality, prolong shelf life and monitor food corruption. Even so, there are still many challenges and limitations in formulation, preparation and application of this new packaging technology that need to be addressed in the future.

Polysaccharide-based porous biopolymers for enhanced bioaccessibility and bioavailability of bioactive food compounds: Challenges, advances, and opportunities

Bioactive food compounds, such as lycopene, curcumin, phytosterols, and resveratrol, have received great attention due to their potential health benefits. However, these bioactive compounds (BCs) have poor chemical stability during processing and low bioavailability after consumption. Several delivery systems have been proposed for enhancing their stability and bioavailability. Among these methods, porous biopolymers have emerged as alternative encapsulation materials, as they have superior properties like high surface area, porosity, and tunable surface chemistry to entrap BCs. This reduces the crystallinity (especially for the lipophilic ones) and particle size, and in turn, increases solubilization and bioavailability. Also, loading BCs into the porous matrix can protect them against environmental stresses such as light, heat, oxygen, and pH. This review introduces polysaccharide-based porous biopolymers for improving the bioaccessibility/bioavailability of bioactive food compounds and discusses their recent applications in the food industry. First, bioaccessibility and bioavailability are described with a special emphasis on the factors affecting them. Then, porous biopolymer fabrication methods, including supercritical carbon dioxide (SC-CO₂ ) drying, freeze-drying, and electrospinning and electrospraying, are thoroughly discussed. Finally, common polysaccharide-based biopolymers (i.e., starch, nanocellulose, alginate, and pectin) used for generating porous materials are reviewed, and their current and potential future food applications are critically discussed.

Introduction to Novel Approaches in the Valorization of Agricultural Wastes and Their Applications

Sustainable food production, waste minimization, and valorization are critical concerns for the agricultural and food industry considering their environmental, social, and economic impacts. Foods are processed to prolong shelf life, make products available out of season, produce new products, and improve nutritional value. During processing, a significant amount of waste is generated, which attracts the attention of scientists and industrialists to valorize the value-added components, including dietary fibers, proteins, and bioactive components. This special issue focuses on the latest developments in waste valorization, covering different industries and methodologies. Within the special issue, waste valorization of some specific food groups, including fruit juice wastes, honeybee byproducts, soybean processing waste, grape pomace materials, and olive mill solid waste, are evaluated. On the other hand, novel approaches to valorizing agricultural wastes and their applications, also covering the recovery of natural pigments with potential health effects, are considered. Besides, nanotechnological and microbial bioconversion methods are used to improve the bioavailability and bioactivity of phytochemicals derived from wastes. It can be concluded that there are still some challenges in waste management and valorization concerning economic, safety, sensory, consumer acceptance, and regulative aspects, and further research is required to overcome these challenges and improve the quality and quantity of value-added products obtained from agricultural wastes and byproducts.

Novel Approaches in the Valorization of Agricultural Wastes and Their Applications

Worldwide, a huge amount of agricultural food wastes and byproducts containing valuable bioactive compounds are generated, especially throughout the entire supply chain. Minimizing food wastes and byproducts is the first option to avoid environmental problems, and to help the economy and the society. Although many countries implement policies to reduce food wastes and byproducts, and different management methods are available to utilize agricultural food wastes, they are still produced annually. Nanotechnological and biotechnological approaches are recently used as novel and green applications to valorize agricultural food wastes and improve their stability and applicability. In this Review, these approaches are covered in detail with given examples. Another valorization way of consumable food waste is using it for functional food production. This Review focuses on specific examples of functional foods with food waste as an ingredient. In addition, the problems and limitations of waste management and valorization methods are investigated, considering future perspectives.

Recent advances in the aqueous applications of PEDOT

Water is ubiquitous in life - from making up the majority of the Earth's surface (by area) to over half of the human body (by weight). It stands to reason that materials are likely to contact water at some point during their lifetime. In the specific case of sensors however, there is a need to consider materials that display stable function while immersed in aqueous applications. This mini-review will discuss the most recent advances (2018 to 2021) in the application of the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) in aqueous environments. At its heart, the use of PEDOT in aqueous applications relies on nanoscale understanding and/or nanoengineered structures and properties. This enables their use in water-based settings such as within the human body or buried in agricultural soils.

Condensed Tannins, a Viable Solution To Meet the Need for Sustainable and Effective Multifunctionality in Food Packaging: Structure, Sources, and Properties

Condensed tannins (CT) have been the focus of increasing interest in the last years as a result of their potent biological properties, which have prompted their use in the food and feed sector as functional ingredients. The possible exploitation of these compounds as multifunctional additives for the implementation of active food packaging has also been recently appreciated. In this perspective, an overview of the structural features, accessible sources, methods of analysis, and functional properties of CT is provided, with the aim of critically emphasizing the opportunities offered by this widespread class of natural phenolic compounds for the rational design of multifunctional and sustainable food packaging materials.

A Review on Plant-Mediated Synthesis of Bimetallic Nanoparticles, Characterisation and Their Biological Applications

The study of bimetallic nanoparticles (BNPs) has constantly been expanding, especially in the last decade. The biosynthesis of BNPs mediated by natural extracts is simple, low-cost, and safe for the environment. Plant extracts contain phenolic compounds that act as reducing agents (flavonoids, terpenoids, tannins, and alkaloids) and stabilising ligands moieties (carbonyl, carboxyl, and amine groups), useful in the green synthesis of nanoparticles (NPs), and are free of toxic by-products. Noble bimetallic NPs (containing silver, gold, platinum, and palladium) have potential for biomedical applications due to their safety, stability in the biological environment, and low toxicity. They substantially impact human health (applications in medicine and pharmacy) due to the proven biological effects (catalytic, antioxidant, antibacterial, antidiabetic, antitumor, hepatoprotective, and regenerative activity). To the best of our knowledge, there are no review papers in the literature on the synthesis and characterisation of plant-mediated BNPs and their pharmacological potential. Thus, an effort has been made to provide a clear perspective on the synthesis of BNPs and the antioxidant, antibacterial, anticancer, antidiabetic, and size/shape-dependent applications of BNPs. Furthermore, we discussed the factors that influence BNPs biosyntheses such as pH, temperature, time, metal ion concentration, and plant extract.

Jabuticaba (Myrciaria jaboticaba) Peel as a Sustainable Source of Anthocyanins and Ellagitannins Delivered by Phospholipid Vesicles for Alleviating Oxidative Stress in Human Keratinocytes

The Brazilian berry scientifically known as jabuticaba is a fruit covered by a dark purple peel that is still rich in bioactives, especially polyphenols. Considering that, this work was aimed at obtaining an extract from the peel of jabuticaba fruits, identifying its main components, loading it in phospholipid vesicles specifically tailored for skin delivery and evaluating their biological efficacy. The extract was obtained by pressurized hot water extraction (PHWE), which is considered an easy and low dissipative method, and it was rich in polyphenolic compounds, especially flavonoids (ortho-diphenols and condensed tannins), anthocyanins (cyanidin 3-O-glucoside and delphinidin 3-O-glucoside) and gallic acid, which were responsible for the high antioxidant activity detected using different colorimetric methods (DPPH, FRAP, CUPRAC and metal chelation). To improve the stability and extract effectiveness, it was incorporated into ultradeformable phospholipid vesicles (transfersomes) that were modified by adding two different polymers (hydroxyethyl cellulose and sodium hyaluronate), thus obtaining HEcellulose-transfersomes and hyaluronan-transfersomes. Transfersomes without polymers were the smallest, as the addition of the polymer led to the formation of larger vesicles that were more stable in storage. The incorporation of the extract in the vesicles promoted their beneficial activities as they were capable, to a greater extent than the solution used as reference, of counteracting the toxic effect of hydrogen peroxide and even of speeding up the healing of a wound performed in a cell monolayer, especially when vesicles were enriched with polymers. Given that, polymer enriched vesicles may represent a good strategy to produce cosmetical and cosmeceutical products with beneficial properties for skin.