Bioavailability, bioactivity and impact on health of dietary flavonoids and related compounds: an update

Abstract

There is substantial interest in the role of plant secondary metabolites as protective dietary agents. In particular, the involvement of flavonoids and related compounds has become a major topic in human nutrition research. Evidence from epidemiological and human intervention studies is emerging regarding the protective effects of various (poly)phenol-rich foods against several chronic diseases, including neurodegeneration, cancer and cardiovascular diseases. In recent years, the use of HPLC-MS for the analysis of flavonoids and related compounds in foods and biological samples has significantly enhanced our understanding of (poly)phenol bioavailability. These advancements have also led to improvements in the available food composition and metabolomic databases, and consequently in the development of biomarkers of (poly)phenol intake to use in epidemiological studies. Efforts to create adequate standardised materials and well-matched controls to use in randomised controlled trials have also improved the quality of the available data. In vitro investigations using physiologically achievable concentrations of (poly)phenol metabolites and catabolites with appropriate model test systems have provided new and interesting insights on potential mechanisms of actions. This article will summarise recent findings on the bioavailability and biological activity of (poly)phenols, focusing on the epidemiological and clinical evidence of beneficial effects of flavonoids and related compounds on urinary tract infections, cognitive function and age-related cognitive decline, cancer and cardiovascular disease.

Berries and anthocyanins: promising functional food ingredients with postprandial glycaemia-lowering effects

“…Unabsorbed anthocyanins reaching the large intestine may be converted to other metabolites by resident colonic bacteria, followed by absorption or excretion in the faeces (42,63,64) . Microbiota can degrade anthocyanins to phenolic acids and aldehydes by splitting the C-ring and modifying the remaining A and B-rings (62) . Some of the main metabolites of microbiota degradation are gallic acid, vanillic acid, homovanilic acid, protocatechuic acid (PCA), syringic acid and 4-hydroxybenzoic acid (55,(65)(66)(67)(68) .…”

Phenolic compounds, bioactive content and antioxidant capacity of the fruits of mulberry (Morus spp.) germplasm in Turkey

“…White mulberries, which are rich in flavonoids, are also known as an important nutritional source for protecting the immune system (Butt et al 2008). Previous studies had revealed that phenolic compounds having a protective effect in coronary heart disease and some types of cancer are also anti-aging owing to their antioxidant characteristics instrumental in eliminating free radicals (Rodriguez-Mateos et al 2014). Because of its high phytochemical content, the black mulberry fruit has been used in folk medicine from old times against several disorders such as nausea, vomiting, digestive disorders, diabetes, hypertension, coughs, anaemia, arthritis, mouth sores, gingival diseases, fever, and fatigue (Gungor and Sengul 2008).…”

Polyphenols and brain health

“…resveratrol) found in grapes, wine, peanuts. For further details of the structures and occurrence of these compounds readers should consult Rodriguez-Mateos (Rodriguez-Mateos et al, 2014), along with the ever expanding Phenol-Explorer database which includes comprehensive information of the polyphenol content of foods (Neveu et al, 2010).…”