Current Nutrition & Food Science - Volume 7, Issue 3, 2011

Dietary lipids are traditionally known for playing a significant role in the development of nutritional-related diseases such as obesity, hyperlipidemia, diabetes, cardiovascular disorders, hypertension or cancer. However, the current concept on lipids and health is changing in the last years towards the clear distinction of individual lipids, since a generalization cannot be stated about dietary lipids as precursors of pathologies. This is because evidences suggest that diverse lipids ingested at specific doses are involved in the prevention and improvement of the management of several diseases. As example, especial attention has been paid to the bioactivity of individual short, medium chain and branched fatty acid as well as conjugated linoleic acid isomers that can be found in milk and dairy products, which are foodstuffs of damaged image due to the traditional consideration of milk fat as unhealthy fat. Other minor lipid compounds with biological activity, such as phospholipids (PLs) are also part of the fat globule membrane of milk fat. PLs are well recognized as important contributors to beneficial effects in human health, being involved in major cell functions such as cell growth, death, senescence, adhesion, migration or cell integrity. Therefore, the analysis of the mechanisms of how dietary PLs are involved in cell functions and their relation to the development or prevention of nutritional-related diseases is under continuous study. On the other hand, lipids can act as bioactive compounds by an indirect way, due to its role as delivery systems of bioactive ingredients. Thus, bioactive compounds such as fatty acids, phenols or vitamins, are examples of bioactive molecules that can be bonded to traditional lipids such as triacylglycerols, PLs, fatty acids or sterols, in order to enhance the handling of bioactive substances for inclusion in foods, or improve its bioavailability and transport to different tissues. This special issue explores some recent advances on bioactive lipids, giving emphasis on 1) the recent findings of those components of the dairy fat traditionally considered to a minor extent; 2) the physiological function, molecular action and genomic bases of dietary PLs and their bioactivity in chronic diseases; and 3) the potential of lipids as delivery systems of bioactive ingredients for inclusion in foods.

Nutritional-related diseases such as obesity, hyperlipidemia, type 2 diabetes, cardiovascular disorders, hypertension or cancer are increasingly prevalent in industrialized countries. Dietary lipids have been found to play a significant role in the prevention and improvement of the management of several of these chronic diseases. Closely to 10% of the intake of total dietary lipids correspond to phospholipids (PLs), which have been recognized as important contributors to their beneficial effects in human health. Bioactive PLs have essential roles as signaling and regulatory molecules, being involved in major cell functions such as cell growth, death, senescence, adhesion, migration or cell integrity. The analysis of the mechanisms of how PLs are involved in these varied cell functions is necessary for understanding and profiting from bioactive PLs action. This review explores the genomic bases of the physiological functions and molecular actions of bioactive PLs, and their effect in the development of chronic diseases.

Current information about the nutritional composition of milk fat is required for the consumer and therefore essential for the successful development of dairy industries as well as marketing their products. The progress in the knowledge concerning some milk fat components that possess biological properties and health benefits beyond their nutritional significance, has a growing interest in the dairy industry to design and formulate products that incorporate specific bioactive components derived from milk. In the last two decades, special attention has been paid to the fatty acid (FA) composition on all short, medium chain and branched fatty acid as well as linoleic conjugated acid (CLA) in milk and dairy products. Trans monounsaturated fatty acids profiles from dairy fat have gained increasing relevance because they may have metabolic properties distinct from those of other origins, hydrogenation reaction for instance. Other minor lipid compounds with biological activity, phospholipids and cholesterol are part of the fat globule membrane. This review summarizes the current knowledge in milk fat research with a brief overview of the importance of dairy lipids as biological molecules with emphasis on the different bioactive compounds present in this fraction.

Delivery systems in the form of lipids have been mainly developed for drugs in the pharmaceutical field, but lipids as delivery systems for bioactive ingredients can be extended to the functional food and nutraceutical fields. Lipid delivery systems may have considerable benefit by enhancing the transport of important bioactive molecules to different tissues, as well as improving the oral bioavailability of poorly water-soluble compounds. On the other hand, formation of lipid delivery systems leads to the lipophilization of compounds, which enhances the lipophile/hydrophile balance of molecules. Furthermore, mutual activity when the carrier used is another biologically active compound is of interest for lipid delivery systems. This review focuses on lipids as delivery systems of carrier-linked bioactive ingredients, namely triacylglycerols, phospholipids, fatty acids and fatty alcohols, sterols and alkylglycerols, as well as their inherent biological activity. The influence on the chemical stability, bioactivity, bioavailability or organ selectivity is addressed. In addition, the impact of lipophilization on other specific effects such as antioxidant will be described. Lipid delivery systems as carriers of bioactive fatty acids, phenolic compounds and vitamins will be the main examples illustrated.

Dysfunctions of the gastrointestinal tract are thought to be related to disturbances or aberrancies of the intestinal microbiota. Nowadays probiotics may represent a solution of choice to balance gut microbiota although they have not been selected for specific subpopulations or disease groups. Since probiotic health benefits are strain specific, it is likely that strains can be selected, aimed at particular groups of patients. Probiotic bacteria have been usually used to treat and prevent some gastrointestinal disturbances such as irritable bowel diseases (IBD) or syndrome (IBS), or diarrhoea and new evidences support the use of probiotics in the prevention and treatment of a number of diseases including atopic diseases, immune disorders, obesity, and diabetes., although new extra-intestinal applications are getting interest of the industry and consumers. This review comprises the current and potential applications of probiotics to improve human health.

Selenium (Se) is an essential element for maintenance of human health. Although it has not been confirmed an essential nutrient in higher plants, there is increasing evidence that Se is a beneficial element for plants, as an antioxidant and a promoter of plant growth. Today, the investigation is directed to elucidate the specific biochemical mechanisms that underlie this positive effect in plants. This ability of some plants to accumulate and transform Se into bioactive compounds has important implications for human nutrition and health. Because Se deficiency is a common problem worldwide, plants are an excellent source of dietary Se than can help to alleviate this problem. It is considered that the beneficial role of Se in human nutrition and health is attributed both to Se compounds and to its presence within selenoproteins; however, it is important to know which Se species are beneficial or detrimental to human nutrition. This review presents the roles of Se in plant and human nutrition; particular attention is paid to the importance of plant Se biochemistry, the strategies to increase Se density in crops by biofortification, the necessity of reaching the correct Se levels through diet and the importance of increased Se to a whole population.

Childhood overweight and obesity is a global epidemic with rising trends in both developed and developing countries. Overweight and obesity are major causes of morbidity during childhood and are important early risk factors for several adult morbidities and mortality. Although the mechanism of overweight development is not fully understood, it is confirmed that overweight occurs as a consequence of imbalance between individual energy intake and energy expenditure. Besides genetic factors, modifiable factors such as family behavior, cultural environment, personal lifestyle choices such as a sedentary lifestyle and unhealthy dietary habits influence the development of obesity resulting in an increased ‘obesogenic’ risk in specific groups of children. So far, previous intervention programs have had limited success in tackling the rising prevalence of obesity. Thus, in addition to treatment and individual approaches, prevention programs targeting the obesogenic environment could be the key strategy for controlling the epidemic of obesity. This article is aimed to present definitions as well as the epidemiology of overweight and obesity. Furthermore, it describes the current knowledge on the multifactorial etiology involving interactions among genetic background and different social and environmental factors. The article critically reviews the current body of evidence regarding the effectiveness of previous interventions to prevent the development of overweight and obesity during childhood. Finally, recommendations for future research are provided which is needed to improve and enable the prevention of obesity in children and adolescents.

The methanolic extract of Erythrina indica L. (Paltemadar) seed materials, an underutilized food legume collected from India was analyzed for antioxidant and health relevant functional properties. The methanolic extract of raw seeds contained total free phenolic content of 11.78 ± 1.17 g catechin equivalent/100 g extract DM. Encouraging levels of ferric reducing/antioxidant power (FRAP, 1213 mmol Fe[II]/mg extract), inhibition of β-carotene degradation (48.26%) and scavenging activity against DPPH (63.46%) and superoxide (44.56%) radicals were exhibited by the raw samples. Further, it also recorded 64.38% of α-amylase and 78.82% of α-glucosidase enzyme inhibition characteristics under in vitro starch digestion bioassay. Sprouting + oil-frying caused an apparent increase on the total free phenolic content and also significantly improved the antioxidant and free radical scavenging capacity of E. indica seeds, while soaking + cooking as well as open-pan roasting treatments showed diminishing effects. Moreover, inhibition of α-amylase and α- glucosidase enzyme activities was declined to 22.48 and 40.91%, respectively during sprouting + oil-frying treatment, which is more desirable for the dietary management of type II diabetic patients.

The enzymatic-HPLC quantitative method is widely used for the determination of non-digestible oligosaccharide. However, the results obtained from the method are inconsistent with some reports. In the present study, we clarified the reason that the existent enzymatic-HPLC method could not accurately measure the quantity of non-digestible oligosaccharide, and then we developed the improved enzymatic-HPLC method for accurate quantification of non-digestible oligosaccharide. When some digestible and non-digestible oligosaccharides were measured by the existent enzymatic-HPLC method, 67% of isomaltooligosaccharide (IMO) was recovered as intact form, and 91% of sucrose and 95% of lactose were recovered as intact form, respectively. This result is questionable because IMO, sucrose and lactose were clearly measured as non-digestible oligosaccharides in this method. However, IMO was readily hydrolyzed and the intact form was not detected by the improved enzymatic-HPLC method which pig small intestinal enzymes were added to the hydrolyzing process in the existent enzymatic-HPLC method. Also, sucrose and lactose were completely hydrolyzed and the intact form were not recovered. The recovery rates of intact fructooligosaccharide (FOS) and resistant maltodextrin (RMD), which are not digested by small intestinal disaccharidase, were 92.1% and 78.8%, respectively. The contradiction appears to demonstrate that thermostable α-amylase and amyloglucosidase may not be able to hydrolyze the low molecular weight oligosaccharides, although they can hydrolyze spontaneously high molecular polysaccharides. In conclusion, the present study strongly suggests that the existent enzymatic-HPLC quantitative method cannot accurately measure non-digestible oligosaccharides, and that the improved enzymatic-HPLC method is suitable for the quantity of oligosaccharides.