In many Western diets, the role of plants has been reduced in favour of more animal-based products and this is now being cited more widely as being the cause of increases in the incidence of diseases such as cancer and cardiovascular disease. This important book covers the biochemistry and nutritional importance of a wide range of phytonutrients, including all the major macronutrients as well as the micronutrients and 'non-essential' nutrients.Phytonutrients is divided into three parts. The first deals with the role of plants in the human diet. Part II, representing the major part of the book covers in turn each of the major phytonutrient groups. Chapters include: non-lipid micronutrients, lipids and steroids, carotenoids, phenolics, vitamins C, E, folate/vitamin B12, phytoestrogens, other phytonutrients and minerals, and anti-nutritional factors. The final part of the book covers the methods used to manipulate levels of phytonutrients in the diet, such as fortification, supplementation and the use of genetically modified plants.Phytonutrients is an essential purchase for nutritionists, food scientists and plant biochemists, particularly those dealing with nutrients from plants, and their use in the human diet.

Preface xiContributors xiiAbbreviations xv1 Plant foods and health 1Judith ButtrissIntroduction 1Historical changes in the plant content of the human diet 1Changing composition of dietary constituents in the past 50 years 5Plants - nutrients and other constituents 6A summary of the evidence linking plant food intake and health 6Coronary heart disease and stroke 9Fruits and vegetables 9Pulses and nuts 13Cereals 15Antioxidant nutrients 17Other bioactive substances 18Antioxidant hypothesis 20Phytosterols and -stanols 20Conclusions for coronary heart disease and stroke 21Cancer 21Fruit and vegetables 21Legumes and nuts 26Foods containing fibre 26Vitamins 26Other plant-derived substances 28Conclusions for cancer 28Type 2 diabetes 29Age-related macular degeneration and cataract 29Age-related cognitive decline 30Chronic obstructive pulmonary disease 31Osteoporosis and bone health 31Plant foods and health: overall conclusions 32Recommendations and current policy on plant food intake 33Fruit and vegetables 33Wholegrain foods 35Current consumption patterns 35Conclusions 39Acknowledgement 402 Carbohydrates and lipids 52Andrew Salter and Gregory TuckerIntroduction 52Major carbohydrates 53Sugars 54Polysaccharides 55Starch 55Cell wall polymers 58Biosynthesis of cell wall polymers 60Cell wall turnover 62Nutritional benefits of plant carbohydrates 64Major sources of dietary fibre within the diet and recommended intakes 64Definition and measurement of dietary fibre 65Physiological effects of dietary fibre 66Lipids 68Synthesis of fatty acids in plants 69Synthesis of glycerolipids in plants 70Modification of plant lipids 73Fatty acid composition of plant foods 76Vegetables 76Cereals 77Fruit 77Oil seeds 77Dietary lipids and human health 79Phytosterols 803 Carotenoids 89Úrsula Flores-Perez and Manuel Rodriguez-ConcepcionIntroduction 89Structure, biosynthesis and function of plant carotenoids 90Dietary sources and health benefits 93Absorption and bioavailability of dietary carotenoids 97Carotenoid type 98Food matrix 98Carotenoid metabolism in humans 99Meeting the dietary demand and consequences for imbalance 101Acknowledgements 1024 Polyphenols 110David Vauzour, Katerina Vafeiadou and Jeremy P. E. SpencerIntroduction 110Polyphenol structure 110Phenolic acids and stilbenes 110Flavonoids 113Biosynthetic routes within the plant 115Shikimic precursor and benzoic acid biosynthesis 115Cinnamic acid biosynthesis 115Stilbene biosynthesis 119Flavonoid biosynthesis 119Major sources within the diet 121Phenolic acids and stilbenes 121Flavonoids 121Flavonols 121Flavanones 122Flavanols 123Flavones 123Anthocyanins 123Isoflavones 123Metabolic fate of dietary polyphenols 124Gastrointestinal tract metabolism 124Colonic metabolism 126Role in human health 127Flavonoids as classical antioxidants 128Non-antioxidant activities of fl avonoids 130Interactions with cell signalling pathways 131Other potential mechanisms of action 133Conclusion 133Summary 134Acknowledgements 1345 Vitamins C and E 146David Gray, John Brameld and Gregory TuckerIntroduction 146Vitamin C: structure and chemistry 146Dietary sources of vitamin C 147Vitamin C: biosynthesis and metabolism in plants 148Vitamin C functions in plants 152Vitamin C manipulation in plants 154Absorption and transport of vitamin C in mammals 155Vitamin E: structure and chemistry 156Dietary sources of vitamin E 159Vitamin E: biosynthetic pathways 159Roles of tocochromanols in plants 161Manipulation of tocochromanol concentration 162Absorption and transport of vitamin E in mammals 164Antioxidant functions of vitamin E 1646 Folate 173Stéphane Ravanel and Fabrice RébeilléIntroduction 173One-carbon metabolism 174Generation and interconversion of C1-units 176Serine-glycine metabolism 176Formate activation 176Histidine catabolism 177Interconvertion of C1-substituted folates 178Utilisation of C1-units 179Methionine synthesis 179Purine ring formation 179Formylation of methionyl-tRNA 180Thymidylate synthesis 180Pantothenate synthesis 180Folate synthesis and distribution in plants 181Biosynthesis of tetrahydrofolate in plants 181Pterin branch 182pABA branch 183Assembly of the pterin, pABA and glutamate moieties 183Reduction and polyglutamylation 184Catabolism and salvage pathway 185Compartmentation and transport of folates 185Subcellular location of folates 185Folate transporters 186Folates distribution in plants 186Physiology of folate in human health and disease 188Absorption 188Transport, storage, catabolism and excretion 189Metabolic and clinical manifestations of folate deficiency 189Diagnosis of folate deficiency 190Folate bioavailability, requirements and food fortification 191Bioavailability 191Dietary intake recommendations 192Dietary sources of folate 192Food fortification 194Prospects for plant foods biofortification 1957 Phytoestrogens 203Helen WisemanIntroduction 203Biosynthesis of phytoestrogens 203Introduction 203Isoflavonoids 203Prenylated flavonoids 205Stilbenes 205Lignans 205Genetic engineering 205Isoflavonoids 206Introduction 206Dietary sources and intakes 206Metabolism and bioavailability 208Isoflavonoids and cancer prevention 211Hormone-dependent cancer prevention by isoflavonoids 211Oestrogens and risk of breast cancer 213Oestrogen receptor-mediated events 213Animal models 215Mechanisms of anticancer action of isoflavonoids 217Clinical studies 219Protection by isoflavonoids against cardiovascular disease 220Cholesterol-lowering and isoflavonoids 220Antioxidant action 222Arterial function 225Cellular effects 226Protection by isoflavonoids against osteoporosis, cognitive decline and menopausal symptoms? 226Osteoporosis 226Menopausal symptoms and cognitive decline 227Isoflavonoids: potential risks 228Lignans 229Introduction 229Production of mammalian lignans 230Cardiovascular disease 230Breast cancer prevention 230Prostate cancer prevention 230Prevention of other types of cancer 231Other health benefits 231Prenylflavonoids 231Stilbenes 233Miroestrol 235Deoxybenzoins 235Coumestans 236Phytoestrogens and human health: conclusions 2368 Plant minerals 254Martin R. Broadley and Philip J. WhiteIntroduction 254Genetic variation in plant mineral concentration 258Introduction 258Between-species genetic variation in plant mineral concentration 258Within-species genetic variation in plant mineral concentration 259Iron and zinc 260Iodine and selenium 263Calcium and magnesium 264Copper 266Has the mineral concentration of crops declined due to breeding for increased yield? 266Evidence for a decline in mineral concentration of horticultural crops 266Is there evidence for a decline in mineral concentration of staple crops? 267A case study on potatoes; a précis of White et al. (2009) 268Index 278