Naturally Occurring Exosome Vesicles as Potential Delivery Vehicle for Bioactive Compounds

Various kinds of vesicles have been produced from plant, animal and inorganic materials for use as delivery vehicles especially in functional food formulation. However, major drawbacks associated with most of them include issues with sustainability, safety, biocompatibility, biorecognition, stability, bioavailability, bioadhesion, generation of reactive species, inefficient encapsulation and protection, and inability to release the bioactive compounds at target regions of the gastrointestinal tract. The use of vesicles innately formed in plant and animal cells as delivery agents would potentially solve most problems associated with the existing nanodelivery systems. Underutilized vesicles, known as exosomes, exist in plant and animal cells, where they play roles in cell communication and nutrient delivery. To date, exosomes have proven to be stable, biocompatible and able to withstand the activity of digestive enzymes until they reach their target locations. However, there is a need to explore better ways of inducing exosome production, to elucidate their physiological roles, and understand their biogenesis in plants, to discover sustainable methods of isolation of high yields of the vesicles. There is also a need to clarify the digestibility and interaction of the exosomes with blood and gastrointestinal fluids. This review highlights the isolation techniques and delivery potential of exosomes, and equally presents research gaps for enhancing the use of the natural vesicles for delivery purposes

First- and second-generation valorisation of wastes and residues occurring in the food supply chain

Despite the high potential to increase sustainability of food systems, wastes and by-products occurring in the food supply chain are currently only partially valorised at different value-added levels. First-generation valorisation strategies that aim at utilisation of complete material streams for production of animal feed, energy, compost and/or specific consumer applications are already widely implemented and experience further dissemination and/or development (e.g. biohydrogen/biohythane production) – either in the form of single processes or as part of cascade utilisations. Second-generation valorisation strategies comprise various forms of fractionised utilisation of material streams. They rely on integration of adapted recovery and conversion procedures for specific components in order to obtain sequentially different classes of products, e.g. fine chemicals, commodity products and biofuels. Such advanced strategies are particularly suitable for wastes and by-products occurring during industrial food processing. Valorisation of food by-products for functional food is an emerging trend

Ribulose-1,5-bisphosphate carboxylase as a sustainable and promising plant source of bioactive peptides for food applications

Background Plant proteins are well-known precursors of bioactive peptides. In translating the peptides into functional foods, the protein sources need to be sustainable and readily available. Ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) is the major enzyme in photosynthesis and photorespiration in plants and some other organisms, and is known to be the most abundant protein on earth. Therefore, RuBisCO is an attractive and sustainable source of bioactive peptides. Scope and approach This review discusses the structure, function, composition and technology for plant RuBisCO extraction, as well as the fractionation and known bioactivities of its enzymatic hydrolysate and peptides. Feasibility of industrial scale up and practical application of the RuBisCO peptides in food were also considered. Key findings and conclusions Several processes are available for extraction of the RuBisCO subunits and some are simple, fast and adaptable for industrial scale production. Work is however needed on recovery of high protein yields with high purity. Most studies reported that peptides, mostly from the large subunit, from enzymatic hydrolysis of spinach or alfalfa RuBisCO possess antihypertensive, opioid-like, secretagogue and food intake stimulating, antioxidant and antimicrobial activities. These properties demonstrate that RuBisCO can be utilized as a sustainable source of peptides with multiple bioactivities for formulation of functional foods

Towards the management of hypertension: Modulation of the renin-angiotensin system by food protein hydrolysates and peptides

In response to the side effects of antihypertensive drugs, dietary and lifestyle modification approaches have become alternative strategies for prevention and modulation of mild hypertension. Moreover, the use of low molecular size bioactive peptides (BAPs) as antihypertensive agents has gained particular attention as a result of the safety, low cost, and consumer preference for natural health products compared to drugs. BAPs are produced by enzymatic hydrolysis of food proteins followed by post-hydrolysis processing to fractionate the active peptides. Antihypertensive BAPs exert their effect mostly by modulating the renin-angiotensin system pathway leading to decrease in vasoactive peptides with concomitant reduction of elevated blood pressure associated with hypertension in animal models and humans. This review revisits the prevalence of hypertension and the molecular basis of activity, bioavailability and safety of BAPS as well as contradictions and controversies on the use of peptides as antihypertensive agents

Chemometric Analysis of the Amino Acid Requirements of Antioxidant Food Protein Hydrolysates

The contributions of individual amino acid residues or groups of amino acids to antioxidant activities of some food protein hydrolysates were investigated using partial least squares (PLS) regression method. PLS models were computed with amino acid composition and 3-z scale descriptors in the X-matrix and antioxidant activities of the samples in the Y-matrix; models were validated by cross-validation and permutation tests. Based on coefficients of the resulting models, it was observed that sulfur-containing (SCAA), acidic and hydrophobic amino acids had strong positive effects on scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and H2O2 radicals in addition to ferric reducing antioxidant power. For superoxide radicals, only lysine and leucine showed strong positive contributions while SCAA had strong negative contributions to scavenging by the protein hydrolysates. In contrast, positively-charged amino acids strongly contributed negatively to ferric reducing antioxidant power and scavenging of DPPH and H2O2 radicals. Therefore, food protein hydrolysates containing appropriate amounts of amino acids with strong contribution properties could be potential candidates for use as potent antioxidant agents. We conclude that information presented in this work could support the development of low cost methods that will efficiently generate potent antioxidant peptide mixtures from food proteins without the need for costly peptide purification

Sustainability in a changing world: integrating human health and wellbeing, urbanisation, and ecosystem services

There is an urgent need to address interlinked sustainability issues in a world challenged by inequality, finite resources and unprecedented changes across Earth’s systems. As Future Earth Fellows, based on our collective expertise in a diverse range of sustainability issues, here we identify a specific need to recognise and respond appropriately to the nexus between human health and wellbeing, urbanisation, and ecosystem services (the ‘WUE nexus’). This nexus is a priority area for research, policy and practice. In particular, it provides a useful pathway to meet the challenges of successful implementation of the Sustainable Development Goals (SDGs). In this brief, we present the following policy recommendations:1. By emphasising urban-rural linkages, foster an integrated approach to ensure food security, food safety, and health promotion;2. Secure resilient livelihoods for all, in particular for vulnerable groups; and3. Integrate co-production of knowledge in science for decision-making, including the co-design of implementation frameworks, and the adoption of a nexus approach.<br/

Food matrix interaction and bioavailability of bioactive peptides : Two faces of the same coin?

Several peptides derived from food protein digestion possess regulatory functions that can lead to health promotion. Such peptides can be used as nutraceuticals and their inclusion as active components of functional food products is increasingly gaining attention. However, physiological evidence to support health benefits is available only in some cases. Low bioavailability of peptides is a major factor that limits their application and often attributed to their selective intestinal uptake and physiological instability when consumed orally. Peptides are notably reactive due to their nucleophilic moieties. This makes them highly susceptible to undergoing structural changes and reactions with the food matrix during product development. Such interactions can reduce the bioaccessibility and bioavailability of peptides, and can also alter their biological activities when measured using in vitro assays. Food matrix-peptide interactions can result in the generation of new compounds, which may be bioactive or undesirable. Moving forward, it is important to select friendly processing methods and less reactive matrices when producing peptides to preserve their structures and improve their bioaccessibility, bioavailability and use in products designed for disease prevention and management

The Role of Food Peptides in Lipid Metabolism during Dyslipidemia and Associated Health Conditions

Animal and human clinical studies have demonstrated the ability of dietary food proteins to modulate endogenous lipid levels during abnormal lipid metabolism (dyslipidemia). Considering the susceptibility of proteins to gastric proteolytic activities, the hypolipidemic functions of proteins are possibly due, in part, to their peptide fragments. Food-derived peptides may directly modulate abnormal lipid metabolism in cell cultures and animal models of dyslipidemia. The peptides are thought to act by perturbing intestinal absorption of dietary cholesterol and enterohepatic bile acid circulation, and by inhibiting lipogenic enzymatic activities and gene expression in hepatocytes and adipocytes. Recent evidence indicates that the hypolipidemic activities of some peptides are due to activation of hepatic lipogenic transcription factors. However, detailed molecular mechanisms and structural requirements of peptides for these activities are yet to be elucidated. As hypolipidemic peptides can be released during enzymatic food processing, future studies can explore the prospects of combating metabolic syndrome and associated complications using peptide-rich functional food and nutraceutical products

Anti-Diabetic Properties of Hydrolysates from Egg White Proteins Using Immobilized Enzymes Followed by in vitro Gastrointestinal Digestion

Background and Objective: Enzyme-assisted hydrolysis of the proteins from food sources is an effective way to generate peptides with various bioactive properties. Furthermore, enzyme immobilization is a way to recycle enzymes for the future uses. The objective of this study was to investigate the effects of neutrase and thermolysin immobilization on the enzyme properties and in vitro anti-diabetic properties of intestinal digests achieved by the simulated digestion of egg white protein hydrolysates. Material and Methods: Neutrase and thermolysin were immobilized on cellulose-coated magnetite nanoparticles. Then, enzyme activity, thermal resistance, reusability and optimum conditions of the egg white protein hydrolysis were assessed. Egg white protein hydrolysates were then digested in vitro and inhibitory activities of the intestinal digests against dipeptidyl peptidase IV (DPP-IV) and α-glucosidase were investigated. Results and Conclusion: Enzymes immobilization resulted in increases in the thermal stabilities of them. Optimum temperatures for the egg white protein hydrolysis increased by 4.0 and 3.2 °C for neutrase and thermolysin, respectively. Digests from the hydrolysates of free neutrase effectively inhibited DPP-IV and α-glucosidase by 17.9 and 29.7%, respectively. These values for the hydrolysates released by the free thermolysin were higher (37.2 and 35.1%, respectively). The enzyme immobilization resulted in a 4.4% decrease in DPP-IV inhibitory activities of the digests for the hydrolysates from neutrase and a 28.6% decrease for those from thermolysin. Decreases in α-glucosidase inhibition due to the immobilization included 9.8% for neutrase and 12.2% for thermolysin for the digests from the hydrolysates. Based on the results from the current study, hydrolysates from the egg white proteins achieved by the free and immobilized neutrase and thermolysin can be used in formulations of the functional foods and nutraceuticals with multifunctional properties