The Molecular Nutrition of Fats

Vinood Patel, Vinood B. Patel

• Publisher: Academic Press
• Year: 2018
• Print ISBN: 9780128112977
• eBook ISBN: 9780128112984
• Topic: Technology & Engineering
• Subtopic: Food Science
• Index: Technology & Engineering

The Molecular Nutrition of Fats presents the nutritional and molecular aspects of fats by assessing their dietary components, their structural and metabolic effects on the cell, and their role in health and disease. Subject areas include molecular mechanisms, membranes, polymorphisms, SNPs, genomic wide analysis, genotypes, gene expression, genetic modifications and other aspects. The book is divided into three sections, providing information on the general and introductory aspects, the molecular biology of the cell, and the genetic machinery and its function. Topics discussed include lipid-related molecules, dietary lipids and lipid metabolism, high fat diets, choline, cholesterol, membranes, trans-and saturated fatty acids, and lipid rafts. Other sections provide comprehensive discussions on G protein-coupled receptors, micro RNA, transcriptomics, transcriptional factors, cholesterol, triacylglycerols, beta-oxidation, cholesteryl ester transfer, beta-oxidation, lysosomes, lipid droplets, insulin mTOR signaling and ligands, and more. - Summarizes molecular nutrition in health as related to fats - Discusses the impact of fats on cancer, heart disease, dementia, and respiratory and intestinal disease - Includes preclinical, clinical and population studies - Covers the genome, the whole body and whole communities - Includes key facts, a mini dictionary of terms and summary points

Section I

General and Introductory Aspects

Outline

Chapter 1. Classes, Nomenclature, and Functions of Lipids and Lipid-Related Molecules and the Dietary Lipids

Chapter 2. Lipid Metabolism: An Overview

Chapter 3. Absorption of Dietary Fat and Its Metabolism in Enterocytes

Chapter 4. Dietary Lipids and Enteric Infection in Rodent Models

Chapter 5. An Overview of Cholesterol Absorption

Chapter 6. Role of Cholesterol in Maintaining Asymmetric Distribution of Phosphatidylserine in Plasma Membranes

Chapter 7. Subcellular Organelles: Lipid Droplets and the Multifunctional Roles

Chapter 8. Lipid Pathway in Liver Cells and Its Modulation by Dietary Extracts

Chapter 9. C-Reactive Protein and Fatty Acids: Public Health Concerns and Implications

Chapter 10. Glycemic Index Meal Feeding and Lipid Profiling

Chapter 11. Fatty Acids, Gut Bacteria, and Immune Cell Function

Chapter 12. Adipose Tissue and Peritoneal Dialysis

Chapter 13. Molecular Nutrition Fats: Lipoprotein(a)

Chapter 14. Trans Fat Intake and Behavior

Chapter 1

Classes, Nomenclature, and Functions of Lipids and Lipid-Related Molecules and the Dietary Lipids

Daniel Gyamfi, Enoch Ofori Awuah, and Stephen Owusu Department of Medical Diagnostics, College of Health Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana

Abstract

This chapter focuses on the classes, nomenclature, and functions of lipids and lipid-related molecules as well as dietary qualities of lipids. Lipids are important biological molecules. They are generally classified into simple, conjugated, and derived lipids, usually because of their structural composition. Their nomenclature remains unique and diverse, with IUPAC-IUB verdict being central in their naming. Lipids play enormous functions in plants and animals from being protective, precursors for other molecules, high-energy stores, and contributing to overall reproductive health. The main lipid constituents in diets include triacylglycerols, esterified cholesterol, and phospholipids. Lipids essentially cannot be avoided in nature.

Keywords

Cholesterol; Classes; Dietary lipids; Fatty acids; Functions; Glycolipids; Lipids; Nomenclature; Phospholipids; Triacylglycerols

1. Introduction

The term lipids represents structurally diverse compounds with different chemical and physical properties. Thus, lipids are a unique category of compounds that are soluble in solvents such as chloroform and ether, and do not generally dissolve in water. Carbon and hydrogen form the chunk of most lipid structures. They may also contain oxygen, nitrogen, phosphorus, sulfur, and other elements (Rodrigo and Alfonso, 2013). Lipids are increasingly becoming important biological molecules for research because of their important roles that are very critical to both animals and plants (Oresic, 2009). This chapter focuses on the classes, nomenclature, and functions of lipids as well as an input on dietary lipids.

2. Classification

Lipids are grouped into different classes, which stem from their structural composition (Fahy et al., 2011). Generally, they are classified as simple lipids, conjugated or compound lipids, and finally derived or precursor lipids (Arneson and Brickell, 2007) (Fig. 1.1). Another classification puts lipids into saponifiable and nonsaponifiable lipids (Jain, 2005). They may also be classified as acyl lipids and isoprenoid lipids (Fahy et al., 2005). These classifications will be considered, and some individual classes explored.

Simple lipids comprise all lipid esters that do not have any other constituents apart from fatty acids and alcohols. Examples of simple lipids include triacylglycerols (fats and oils) and waxes (Arneson and Brickell, 2007; Fahy et al., 2011). Conjugated lipids comprise all lipid esters that possess additional groups together with fatty acids and alcohols ( Fahy et al., 2005; 2011). They include phospholipids and glycolipids. Derived lipids are lipids that are obtained when simple or conjugated lipids are hydrolyzed (Arneson and Brickell, 2007). Fatty acids, steroids, terpenes, carotenoids, and mono and diglycerides are among this category of lipids.

Some lipids are hydrolyzable by heat, alkalis, and other solutions. Such lipids are called saponifiable lipids. The end products from the process are usually fatty acids and glycerol. Triacylglycerols and phospholipids are examples of such lipids. On the other hand, some lipids are not hydrolyzable. Terpenes and steroids are nonsaponifiable lipids.

Lipids that contain fatty acids as the main nonpolar group are referred to as acyl lipids ( Fahy et al., 2005; 2011). Examples are triacylglycerol, phospholipids, waxes, eicosanoids, and sphingomyelins. Lipids that contain five carbon isoprene units are called isoprenoids. They include lipid vitamins, carotenoids, ubiquinones, and plastoquinones.

2.1. Simple Lipids

2.1.1. Triacylglycerol

Lipids that contain three molecules of fatty acids and a molecule of glycerol are called triacylglycerols. They are usually called oils when liquid or fats when solid at room temperature. This property occurs as a result of length of fatty acid chains attached to the glycerol unit and the degree of saturation (Jain, 2005; Brandt, 2012). Those that are oils are composed of short-chain unsaturated triacylglycerols, whereas the solids are composed of long-chain unsaturated triacylglycerols (Pokorny and Dostalova, 2009).

Figure 1.1 Classification of lipids.Lipids generally are grouped into simple, conjugated, and derived lipids. Simple lipids consist of fatty acids and alcohol, whereas conjugated lipids have additional molecules together with what the simple lipids contain. Derived lipids are lipids obtained upon hydrolysis of simple or compound lipids.

They are not usually associated with membranes, however, they constitute the largest proportion of storage fats that are present in plants and animals (Jain, 2005). They may contain one type of fatty acid. In this case, they are considered as simple triacylglycerols. This means the three fatty acids attached to the glycerol are the same. They c...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Contributors
• Section I. General and Introductory Aspects
• Section II. Molecular Biology of the Cell
• Section III. Genetic Machinery and Its Function
• Index