Preface

The last 20 years have evidenced a dramatic increase in research related to the health benefits of berries and berry bioactive compounds. Novel insights into the diverse composition and structure of berry phytochemicals, their bioavailability, metabolism and impact on the gut microbiome are among the key areas that have been avidly investigated. Additionally, research on the health benefits of edible berries, their bioactive compounds and related metabolites has also exploded, resulting in new knowledge regarding their role in chronic diseases, their molecular mode of action and their clinical significance in promoting health and preventing chronic disease. Their beneficial impact on chronic diseases such as cardiovascular disease, diabetes mellitus and cancer and their role in attenuating inflammation and impacting the gut microbiome has been documented in in vitro, in vivo and clinical studies. “Berries and Berry Bioactive Compounds in Promoting Health” reviews state-of-the-art research findings in this area. This comprehensive book, comprised of 13 chapters, brings together international experts in their corresponding fields to review the current literature, identify knowledge gaps and limitations of the current research and propose future directions. Its uniqueness lies in its approach to presenting recent and comprehensive science-based evidence on areas that have been largely and robustly researched, focusing on human intervention studies, molecular mode of action and intraindividual responses to dietary interventions.

Unique topics covered include the chemistry and analytical methods of detection of berry bioactive compounds, bioavailability, metabolism and factors that affect them, including individual variability, interaction with the gut microbiome and their role and mechanism(s) of action on chronic diseases such as cardiovascular disease, diabetes mellitus, obesity-induced inflammation, neurodegenerative diseases, cancer and wound healing.

To advance research on the health benefits of berries and their bioactive-containing compounds, the complexity of chemical structures and diversity of the bioactive compounds contained in berries necessitate sophisticated and advanced analytical methodologies. Chapter 1 presents a summary of current practices, focusing on modern analytical techniques used in the analysis of berry bioactives in foods and biological samples, with tips for quality assurance and reporting practices.

The bioavailability and metabolism of berry (poly)phenols is discussed in Chapter 2, which explores recent evidence demonstrating that contrary to previous beliefs, berry (poly)phenols are highly bioavailable as a result of the action of the gut microbiota that enable phenolic catabolites to be absorbed in substantial amounts. As a result, the complexity of the composition of the colonic microflora has been associated with inter-individual variability and the classification of subjects as non-, low- and high-producers of phenolic catabolites. Inter-individual variability is also responsible for the conflicting evidence we observe in human studies after dietary berry interventions. Chapter 3 explores and addresses factors of inter-individual variability in cardiometabolic health following berry (poly)phenol consumption from evidence from human clinical trials, reviews and meta-analyses of randomized controlled trials.

Currently, berries are being investigated as a new potential arsenal of antimicrobials and prebiotics because of their ability to selectively inhibit enteric pathogens while promoting the growth of beneficial microorganisms. The critical role of gut microbiota in berry bioactive compound metabolism and their resultant role in health, as well as the specific constituents of berries and microorganisms that support this beneficial relationship, are presented in Chapter 4.

Evidence from recent advances of the role of dietary berries in cardiovascular disease and their molecular mechanisms involved has been documented from epidemiological, clinical and animal studies. Specifically, berries have increasingly been demonstrated to exert cardiovascular-protective effects, including the beneficial modulation of vascular function (Chapter 5) by acting on multiple targets such as activating the endothelial nitric oxide signaling pathway, suppressing endothelial inflammation, modulating redox signaling, altering lipid metabolism and modifying vascular glycocalyx (Chapter 6).

Upon examining the role of berries in cognition and cognitive function with age from epidemiological as well as animal and human intervention studies, it has been documented that diets rich in berries are associated with a reduced risk of cognitive decline with age and improvements in cognitive function. This area is increasingly being explored recently, considering neurodegenerative diseases such as Alzheimer's, Parkinson's, amyotrophic lateral sclerosis and others (Chapter 7). A review of the mechanisms of several neurodegenerative diseases and the potential of berry flavonoids, in particular anthocyanins, and their metabolites in tackling the mechanisms behind the onset and the progression of neurodegenerative diseases to elucidate potential targets and new trends in the future of neurodegenerative research is also reviewed (Chapter 8).

Evidence from in vitro and in vivo studies indicates an array of beneficial effect for berries against cancer and highlights some mechanisms including reactive species scavenging and inflammasome suppression (Chapter 9). Since there is limited clinical research corroborating these findings, it is challenging to identify dietary doses and establish dietary recommendations at this time.

A review of the last 20 years of observational and clinical studies on the relationship between intake of dietary berries and type 2 diabetes mellitus (T2DM) indicate that long-term dietary berry intake is associated with a lower risk of the disease in adults, supporting the consumption of dietary berries to prevent, delay, and treat T2DM (Chapter 10).

Data on the relationship between the intake of berries and capacity to counteract obesity-induced inflammation in human intervention trials indicate that berries may help mitigate the inflammatory state in overweight/obese subjects without having a direct effect on obesity (Chapter 11). The main molecular pathways involved in the observed beneficial effects on chronic inflammation from in vitro and animal studies are explored (Chapter 12).

A recent area of research has focused on wound healing and the role of berries and berry (poly)phenols. The wound healing potential of various bioactive molecules is presented and discussed (Chapter 13).

This book is directed at researchers and scientists working in biomedical sciences and conducting research in the area of berries and their bioactive compounds; health care professionals, i.e., nutritionists, dietitians and clinicians; nutraceutical and natural food products developers (industry) and food regulators.

We would like to thank the staff at the Royal Society of Chemistry, Liv Towers, Katie Morrey and Nicki Dennis, for their professionalism and support, and the production team for their attention to detail and timely production of the book. Additional thanks go to the contributing authors for their professional collaboration, scholarly reviews and timely submission of their chapters. We also thank our families for their constant understanding and support in realizing this book.

Dorothy Klimis-Zacas PhD, FACN and Anna Rodriquez-Matteos PhD