Food matrix-flavonoid interactions and their effect on bioavailability

Flavonoids and the gut microbiome: a powerful duo for brain health

Flavonoids, a class of polyphenolic compounds, are widely distributed in plant-based foods and have been recognized for their potential to promote overall health and well-being. Flavonoids in fruits and vegetables offer various beneficial effects such as anti-aging, anticancer, and anti-inflammatory properties. Flavonoids have been extensively studied for their neuroprotective properties, which are attributed to their ability to cross the blood-brain barrier and interact with neural cells. Factors like gut microbiota composition, age, genetics, and diet can impact how well flavonoids are absorbed in the gut. The gut microbiota can enhance the absorption of flavonoids through enzymatic processes, making microbiota composition a key factor influenced by age, genetics, and diet. Flavonoids can modulate the gut microbiota through prebiotic and antimicrobial effects, affecting the production of beneficial microbial metabolites like short-chain fatty acids (SCFAs) such as butyrate, which play a role in brain function and health. The gut microbiome also modulates the immune system, which is critical for preventing neuroinflammation. Additionally, flavonoids can benefit mental and psychological health by influencing anti-inflammatory signaling pathways in brain cells and increasing the absorption of tyrosine and tryptophan, precursors to neurotransmitters like serotonin, dopamine, norepinephrine, adrenaline, and gamma-aminobutyric acid (GABA). The flavonoid-gut microbiome axis is a complex and multifaceted relationship that has significant implications for neurological health. This review will explore how genetic and environmental factors can impact flavonoid absorption and the positive effects of flavonoids on brain health and the gut microbiota network.

Probabilistic Modelling of the Food Matrix Effects on Curcuminoid's In Vitro Oral Bioaccessibility

The bioaccessibility of bioactive compounds plays a major role in the nutritional value of foods, but there is a lack of systematic studies assessing the effect of the food matrix on bioaccessibility. Curcuminoids are phytochemicals extracted from Curcuma longa that have captured public attention due to claimed health benefits. The aim of this study is to develop a mathematical model to predict curcuminoid's bioaccessibility in biscuits and custard based on different fibre type formulations. Bioaccessibilities for curcumin-enriched custards and biscuits were obtained through in vitro digestion, and physicochemical food properties were characterised. A strong correlation between macronutrient concentration and bioaccessibility was observed (p = 0.89) and chosen as a main explanatory variable in a Bayesian hierarchical linear regression model. Additionally, the patterns of food matrix effects on bioaccessibility were not the same in custards as in biscuits; for example, the hemicellulose content had a moderately strong positive correlation to bioaccessibility in biscuits (p = 0.66) which was non-significant in custards (p = 0.12). Using a Bayesian hierarchical approach to model these interactions resulted in an optimisation performance of r2 = 0.97 and a leave-one-out cross-validation score (LOOCV) of r2 = 0.93. This decision-support system could assist the food industry in optimising the formulation of novel food products and enable consumers to make more informed choices.

The microbiota-gut-brain-immune interface in the pathogenesis of neuroinflammatory diseases: a narrative review of the emerging literature

Importance

Research is beginning to elucidate the sophisticated mechanisms underlying the microbiota-gut-brain-immune interface, moving from primarily animal models to human studies. Findings support the dynamic relationships between the gut microbiota as an ecosystem (microbiome) within an ecosystem (host) and its intersection with the host immune and nervous systems. Adding this to the effects on epigenetic regulation of gene expression further complicates and strengthens the response. At the heart is inflammation, which manifests in a variety of pathologies including neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and Multiple Sclerosis (MS).

Observations

Generally, the research to date is limited and has focused on bacteria, likely due to the simplicity and cost-effectiveness of 16s rRNA sequencing, despite its lower resolution and inability to determine functional ability/alterations. However, this omits all other microbiota including fungi, viruses, and phages, which are emerging as key members of the human microbiome. Much of the research has been done in pre-clinical models and/or in small human studies in more developed parts of the world. The relationships observed are promising but cannot be considered reliable or generalizable at this time. Specifically, causal relationships cannot be determined currently. More research has been done in Alzheimer's disease, followed by Parkinson's disease, and then little in MS. The data for MS is encouraging despite this.

Conclusions and relevance

While the research is still nascent, the microbiota-gut-brain-immune interface may be a missing link, which has hampered our progress on understanding, let alone preventing, managing, or putting into remission neurodegenerative diseases. Relationships must first be established in humans, as animal models have been shown to poorly translate to complex human physiology and environments, especially when investigating the human gut microbiome and its relationships where animal models are often overly simplistic. Only then can robust research be conducted in humans and using mechanistic model systems.

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.