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Editorial overview: Functional foods and nutrition
Available online at www.sciencedirect.com
ScienceDirect Editorial overview: Functional foods and nutrition Rotimi Aluko Current Opinion in Food Science 2016, 8:vii–ix For a complete overview see the Issue Available online 6th April 2016 http://dx.doi.org/10.1016/j.cofs.2016.04.001 2214-7993/# 2016 Elsevier Ltd. All rights reserved.
Rotimi Aluko
Department of Human Nutritional Sciences, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2 e-mail: [email protected] Dr. Rotimi Aluko, a Certified Food Scientist, is a Professor in the Department of Human Nutritional Sciences at the University of Manitoba, Winnipeg, Canada. In 1996, he obtained a PhD degree in Food Science from the University of Guelph, Ontario, Canada. His research program focuses on structure– function properties of food proteins as well as the development of natural food proteinderived bioactive peptides, especially for the prevention and/or management of hypertension and oxidative stress. He is the author of a text book titled ‘Functional Foods and Nutraceuticals’, which is used as a teaching reference material by several undergraduate programs. He has published 137 peer-reviewed journal articles in addition to several book chapters and two United States Patents. One of the patents provides the intellectual property for a commercial antihypertensive pea protein hydrolysate that is currently sold in Canada. From 2011 to 2012, he served as the National President of the Canadian Institute of Food Science and Technology (CIFST). He has also served (2014–2015) as Chair of the Nutraceuticals and Functional Foods Division of the Institute of Food Technologists as well as Chair of the Protein and Co-Products Division (2008– 2010) of the American Oil Chemists’ Society. He is the 2015 recipient of the CIFST William
www.sciencedirect.com
The twin topics of ‘Nutrition’ and ‘Functional Foods’ constitute an increasingly popular area of research, especially within the context of interdisciplinary research. The relationships between the two subject areas have become so close that it is sometimes difficult to determine where functional foods research end and where nutrition starts. However, what is not in doubt is that the intertwined nature of research objectives within these two subject areas has led to identification of commonly found food nutrients that play substantial roles in human health improvement. Functional foods have been traditionally defined as products that are consumed in the form of regular foods or as part of a normal diet but apart from providing nutrients for normal physiological functions, these novel foods can prevent or even treat metabolic disorders. Therefore, functional foods can be viewed as an applied subject within nutrition but as a tool to maintain or restore homeostasis in humans. The attraction of functional foods has been primarily that they are less toxic to the human body than synthetic drugs; therefore, long-term uses may have no severe negative effects. Thus the potential use of nutrients as therapeutic agents in human health is the focus of this special issue, which consists of 11 articles written by globally recognized leaders in Functional Foods and Nutrition research. Polyphenols are now recognized to possess various bioactive properties that can positively impact human health. Wu et al. provides a detailed view of the role of polyphenols in positively modulating genetic information such that cancer-causing aberrations are prevented or repaired. Through down-regulation of the cellular expression of cancer-causing signaling agents and suppression of carcinogenic genes, polyphenols can prevent cell division and metastasis while promoting apoptosis. Polyphenols also act as anticancer agents through enhanced cellular expression of tumor-suppressor genes. Plasteins are reformulated proteins mainly resulting from enzymatic or nonenzymatic packaging of already hydrolyzed peptides. The occurrence of plasteins during certain protein hydrolysis processes has long been demonstrated but their use as bioactive agents has attracted little attention. Udenigwe and Rajendran provide a detailed historical overview of plasteins with emphasis on their potential roles as metal chelating, antioxidant, antihypertensive and hypolipidemic agents. Specifically, plasteins have been shown to enhance cellular integrity in the presence of oxidative agents while the presence of hydrophobic patches promote interactions with bile acids, which serves as an effective means for fecal expulsion and reduction in blood cholesterol. Current Opinion in Food Science 2016, 8:vii–ix
viii Functional foods and nutrition
J. Eva Award for outstanding research and service contributions to the Food Industry. He currently serves as the Editor-in-Chief for the Journal of Food Biochemistry as well as an Associate Editor for Journal of Functional Foods and Current Topics in Nutraceutical Research.
The introduction of glycemic index concept means that contributions of various dietary carbohydrates to obesity and diabetes can be scientifically evaluated. Since excess calories are a known causative factor for various chronic diseases, dietary agents that reduce or prevent total carbohydrate digestion are valuable health-promoting tools. As reviewed by Amoako and Awika, polyphenolic compounds possess ability to interact with amylose through hydrophobic interactions, which produce less digestible nutrient complexes. However, the presence of multiple hydroxyl groups on polyphenols can also contribute to increased interaction with sugars (also polyhydroxyl compounds) through hydrogen bond formation. The presence of multiple hydrogen bonds maintains a cohesive polyphenol–starch complex that is less digestible by gastrointestinal carbohydrases. By reducing carbohydrate digestion rate, dietary polyphenols could be used to regulate blood glucose levels with potential health benefits for obese or diabetic people. Peptides may also function as anti-diabetic agents as illustrated by the detailed review of Nongonierma and FitzGerald. These peptides work by inhibiting dipeptidyl peptidase IV (DPP-IV), an enzyme that breaks down incretins and cause reduced insulin production, which contributes to diabetes development. Their review provides information on the types and positions of amino acids that enhance peptide potency against DPP-IV with scientific evidence on the in vitro and in vivo effects. Uncontrolled oxidative stress contributes to development of an inflammatory state that provides an environment for the pathogenesis of chronic diseases. The review by Gu and Wu provides detailed information on the potential role of food protein-derived peptides as antioxidative and antiinflammatory agents for the prevention of cardiovascular diseases (CVD). As an antioxidant, the peptides prevent vascular remodeling and endothelial dysfunction to ameliorate hypertensive conditions. Similarly, antioxidant peptides ameliorate diabetes by interfering with mitochondrial superoxide production. Gu and Wu also reviewed scientific information relating to the anti-inflammatory activity of peptides through modulation of cytokine production. In a similarly detailed review, Zhang and Tsao reported the ability of polyphenolic compounds to act as antioxidant and anti-inflammatory agents. In addition to the structural information on several potentially bioactive polyphenols, Zhang and Tsao reviewed in vitro and in vivo evidence that support the role of polyphenolic compounds as free radical scavengers, electron donators and attenuators of pro-inflammatory cytokine production. Consumption of high protein diets was once a popular fad against metabolic syndrome, especially in North America. But in the review of Wojcik et al., scientific evidence for the health benefits of high protein diets is contradictory. For example, no substantial benefit with respect to obesity was associated with high protein diets; in fact weight gain was observed in several human trials. Similarly while some studies showed beneficial effects of high protein diet in reducing insulin resistance, others showed that consumption of animal proteins in particular had negative effects. By contrast, high protein diets seem to reduce blood lipids, especially triglycerides while beneficial effects on blood pressure reduction have been reported. The negative effect on blood lipids may be a contributing factor to the reduced incidence of non-alcoholic fatty liver disease associated with high protein diets. Karboune and Khodaei provided a review of the properties and potential health effects of dietary polysaccharides, especially as prebiotics. Lack of gastrointestinal upper tract digestion of the prebiotic polysaccharides makes
Current Opinion in Food Science 2016, 8:vii–ix
www.sciencedirect.com
Editorial overview Aluko ix
them available as foods for the growth and multiplication of colon microbiota, specifically those that impart health benefits. But the polysaccharides can also perform as anticancer and hypocholesterolemic agents through their ability to reduce galectin-3 expression and prevent cholesterol reabsorption, respectively in the gastrointestinal tract. The phytochemical effects of Morinda citrifolia (‘Noni’) plant was reviewed by Ahmad et al. with evidence indicating potential uses as an anti-cancer agent through immune-potentiating activities. Antioxidant and antibacterial activities are also potential applications of various parts of the Noni plant. Samad and Ismail provided a detailed review of the applications of vinegar as a potential therapeutic agent for the prevention and treatment of human chronic diseases, including cardiovascular disorders, obesity, cancer and microbial infections. The potency of vinegar may be attributed to the acetic acid as well as the presence of polyphenolic compounds such as chlorogenic acid, gallic acid and caffeic acid. CVD modulation was also examined through a detailed review by Bhullar and Udenigwe who discussed current evidence
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on the therapeutic potential of resveratrol. While the wide variations in resveratrol doses during human clinical trials make comparisons difficult, the overall trend suggests beneficial effects as a cardioprotective agent. This is because in various human trials, oral administration of resveratrol led to lower blood pressure, reduced intensity of atherosclerosis and reduced risk of secondary myocardial infarction. These extensive reviews provide detailed information on the structural and functional properties of various foodderived bioactive compounds with emphasis on possible mechanisms of action. This issue contains a diversity of article topics ranging from proteins and peptides to polysaccharides and polyphenols in combination with varied bioactive properties such as antioxidant, anti-inflammatory, antidiabetic, anti-cancer, antihypertensive and antiobesity. Therefore, this issue could be viewed as an authoritative source of useful health promotion information for functional food and nutrition researchers as well policy makers and even the general public.
Current Opinion in Food Science 2016, 8:vii–ix
ScienceDirect Editorial overview: Functional foods and nutrition Rotimi Aluko Current Opinion in Food Science 2016, 8:vii–ix For a complete overview see the Issue Available online 6th April 2016 http://dx.doi.org/10.1016/j.cofs.2016.04.001 2214-7993/# 2016 Elsevier Ltd. All rights reserved.
Rotimi Aluko
Department of Human Nutritional Sciences, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2 e-mail: [email protected] Dr. Rotimi Aluko, a Certified Food Scientist, is a Professor in the Department of Human Nutritional Sciences at the University of Manitoba, Winnipeg, Canada. In 1996, he obtained a PhD degree in Food Science from the University of Guelph, Ontario, Canada. His research program focuses on structure– function properties of food proteins as well as the development of natural food proteinderived bioactive peptides, especially for the prevention and/or management of hypertension and oxidative stress. He is the author of a text book titled ‘Functional Foods and Nutraceuticals’, which is used as a teaching reference material by several undergraduate programs. He has published 137 peer-reviewed journal articles in addition to several book chapters and two United States Patents. One of the patents provides the intellectual property for a commercial antihypertensive pea protein hydrolysate that is currently sold in Canada. From 2011 to 2012, he served as the National President of the Canadian Institute of Food Science and Technology (CIFST). He has also served (2014–2015) as Chair of the Nutraceuticals and Functional Foods Division of the Institute of Food Technologists as well as Chair of the Protein and Co-Products Division (2008– 2010) of the American Oil Chemists’ Society. He is the 2015 recipient of the CIFST William
www.sciencedirect.com
The twin topics of ‘Nutrition’ and ‘Functional Foods’ constitute an increasingly popular area of research, especially within the context of interdisciplinary research. The relationships between the two subject areas have become so close that it is sometimes difficult to determine where functional foods research end and where nutrition starts. However, what is not in doubt is that the intertwined nature of research objectives within these two subject areas has led to identification of commonly found food nutrients that play substantial roles in human health improvement. Functional foods have been traditionally defined as products that are consumed in the form of regular foods or as part of a normal diet but apart from providing nutrients for normal physiological functions, these novel foods can prevent or even treat metabolic disorders. Therefore, functional foods can be viewed as an applied subject within nutrition but as a tool to maintain or restore homeostasis in humans. The attraction of functional foods has been primarily that they are less toxic to the human body than synthetic drugs; therefore, long-term uses may have no severe negative effects. Thus the potential use of nutrients as therapeutic agents in human health is the focus of this special issue, which consists of 11 articles written by globally recognized leaders in Functional Foods and Nutrition research. Polyphenols are now recognized to possess various bioactive properties that can positively impact human health. Wu et al. provides a detailed view of the role of polyphenols in positively modulating genetic information such that cancer-causing aberrations are prevented or repaired. Through down-regulation of the cellular expression of cancer-causing signaling agents and suppression of carcinogenic genes, polyphenols can prevent cell division and metastasis while promoting apoptosis. Polyphenols also act as anticancer agents through enhanced cellular expression of tumor-suppressor genes. Plasteins are reformulated proteins mainly resulting from enzymatic or nonenzymatic packaging of already hydrolyzed peptides. The occurrence of plasteins during certain protein hydrolysis processes has long been demonstrated but their use as bioactive agents has attracted little attention. Udenigwe and Rajendran provide a detailed historical overview of plasteins with emphasis on their potential roles as metal chelating, antioxidant, antihypertensive and hypolipidemic agents. Specifically, plasteins have been shown to enhance cellular integrity in the presence of oxidative agents while the presence of hydrophobic patches promote interactions with bile acids, which serves as an effective means for fecal expulsion and reduction in blood cholesterol. Current Opinion in Food Science 2016, 8:vii–ix
viii Functional foods and nutrition
J. Eva Award for outstanding research and service contributions to the Food Industry. He currently serves as the Editor-in-Chief for the Journal of Food Biochemistry as well as an Associate Editor for Journal of Functional Foods and Current Topics in Nutraceutical Research.
The introduction of glycemic index concept means that contributions of various dietary carbohydrates to obesity and diabetes can be scientifically evaluated. Since excess calories are a known causative factor for various chronic diseases, dietary agents that reduce or prevent total carbohydrate digestion are valuable health-promoting tools. As reviewed by Amoako and Awika, polyphenolic compounds possess ability to interact with amylose through hydrophobic interactions, which produce less digestible nutrient complexes. However, the presence of multiple hydroxyl groups on polyphenols can also contribute to increased interaction with sugars (also polyhydroxyl compounds) through hydrogen bond formation. The presence of multiple hydrogen bonds maintains a cohesive polyphenol–starch complex that is less digestible by gastrointestinal carbohydrases. By reducing carbohydrate digestion rate, dietary polyphenols could be used to regulate blood glucose levels with potential health benefits for obese or diabetic people. Peptides may also function as anti-diabetic agents as illustrated by the detailed review of Nongonierma and FitzGerald. These peptides work by inhibiting dipeptidyl peptidase IV (DPP-IV), an enzyme that breaks down incretins and cause reduced insulin production, which contributes to diabetes development. Their review provides information on the types and positions of amino acids that enhance peptide potency against DPP-IV with scientific evidence on the in vitro and in vivo effects. Uncontrolled oxidative stress contributes to development of an inflammatory state that provides an environment for the pathogenesis of chronic diseases. The review by Gu and Wu provides detailed information on the potential role of food protein-derived peptides as antioxidative and antiinflammatory agents for the prevention of cardiovascular diseases (CVD). As an antioxidant, the peptides prevent vascular remodeling and endothelial dysfunction to ameliorate hypertensive conditions. Similarly, antioxidant peptides ameliorate diabetes by interfering with mitochondrial superoxide production. Gu and Wu also reviewed scientific information relating to the anti-inflammatory activity of peptides through modulation of cytokine production. In a similarly detailed review, Zhang and Tsao reported the ability of polyphenolic compounds to act as antioxidant and anti-inflammatory agents. In addition to the structural information on several potentially bioactive polyphenols, Zhang and Tsao reviewed in vitro and in vivo evidence that support the role of polyphenolic compounds as free radical scavengers, electron donators and attenuators of pro-inflammatory cytokine production. Consumption of high protein diets was once a popular fad against metabolic syndrome, especially in North America. But in the review of Wojcik et al., scientific evidence for the health benefits of high protein diets is contradictory. For example, no substantial benefit with respect to obesity was associated with high protein diets; in fact weight gain was observed in several human trials. Similarly while some studies showed beneficial effects of high protein diet in reducing insulin resistance, others showed that consumption of animal proteins in particular had negative effects. By contrast, high protein diets seem to reduce blood lipids, especially triglycerides while beneficial effects on blood pressure reduction have been reported. The negative effect on blood lipids may be a contributing factor to the reduced incidence of non-alcoholic fatty liver disease associated with high protein diets. Karboune and Khodaei provided a review of the properties and potential health effects of dietary polysaccharides, especially as prebiotics. Lack of gastrointestinal upper tract digestion of the prebiotic polysaccharides makes
Current Opinion in Food Science 2016, 8:vii–ix
www.sciencedirect.com
Editorial overview Aluko ix
them available as foods for the growth and multiplication of colon microbiota, specifically those that impart health benefits. But the polysaccharides can also perform as anticancer and hypocholesterolemic agents through their ability to reduce galectin-3 expression and prevent cholesterol reabsorption, respectively in the gastrointestinal tract. The phytochemical effects of Morinda citrifolia (‘Noni’) plant was reviewed by Ahmad et al. with evidence indicating potential uses as an anti-cancer agent through immune-potentiating activities. Antioxidant and antibacterial activities are also potential applications of various parts of the Noni plant. Samad and Ismail provided a detailed review of the applications of vinegar as a potential therapeutic agent for the prevention and treatment of human chronic diseases, including cardiovascular disorders, obesity, cancer and microbial infections. The potency of vinegar may be attributed to the acetic acid as well as the presence of polyphenolic compounds such as chlorogenic acid, gallic acid and caffeic acid. CVD modulation was also examined through a detailed review by Bhullar and Udenigwe who discussed current evidence
www.sciencedirect.com
on the therapeutic potential of resveratrol. While the wide variations in resveratrol doses during human clinical trials make comparisons difficult, the overall trend suggests beneficial effects as a cardioprotective agent. This is because in various human trials, oral administration of resveratrol led to lower blood pressure, reduced intensity of atherosclerosis and reduced risk of secondary myocardial infarction. These extensive reviews provide detailed information on the structural and functional properties of various foodderived bioactive compounds with emphasis on possible mechanisms of action. This issue contains a diversity of article topics ranging from proteins and peptides to polysaccharides and polyphenols in combination with varied bioactive properties such as antioxidant, anti-inflammatory, antidiabetic, anti-cancer, antihypertensive and antiobesity. Therefore, this issue could be viewed as an authoritative source of useful health promotion information for functional food and nutrition researchers as well policy makers and even the general public.
Current Opinion in Food Science 2016, 8:vii–ix