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Topics in nutrition and food science.

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1 Topics in nutrition and food science.
Dr M. Altamimi

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3 Characteristics of Modern life
Urbanisation Ready to eat food, fast food and processed food. High calories (fat and carbohydrate) low fibre. Low in vitamins and minerals. Packaging. Not natural preservation. Refrigeration and freezing. Less physical activity.

4 Office based jobs. Chronic diseases, obesity etc. Aging, people live longer.

5 Diet – together with physical exercise – plays a major role when we try to prevent or postpone the onset of chronic conditions such as the metabolic syndrome. The food industry has already reacted to this challenge and a large number of products have been either reformulated or re-positioned to meet the current need for healthier foods.

6 WHO Chronic diseases are diseases of long duration and generally slow progression. Chronic diseases are by far the leading cause of mortality in the world, representing 63% of all deaths. 36 million people died from chronic disease in 2008.

7 Noncommunicable diseases
Cardiovascular diseases account for most NCD deaths, or 17 million people annually, followed by cancer (7.6 million), respiratory disease (4.2 million), and diabetes (1.3 million). These four groups of diseases account for around 80% of all NCD deaths, and share four common risk factors: tobacco use physical inactivity the harmful use of alcohol and poor diets.

8 Bad habits

9 Stages of life and R F In the uterus:
intrauterine growth retardation (IUGR); premature delivery of a normal growth for gestational age fetus over nutrition in utero Intergenerational factors.

10 Infancy: Retarded growth in infancy can be a reflected in a failure to gain weight and a failure to gain height. Both retarded growth and excessive weight or height gain can be factors in later incidence of chronic disease. Such as CVD There is increasing evidence that among term and pre-term infants, breastfeeding is associated with significantly lower blood pressure levels in childhood. Consumption of formula instead of breast milk in infancy has also been shown to increase diastolic and mean arterial blood pressure in later life. Obesity (type 1 diabetes, coeliac disease, some childhood cancers, inflammatory bowel disease) have also been associated with infant feeding on breast-milk substitutes and short-term breastfeeding

11 Childhood low growth in childhood and an increased risk of CHD has been described, irrespective of size at birth. Relative weight in adulthood and weight gain have been found to be associated with increased risk of cancer of the breast, colon, rectum, prostate and other sites. Higher blood pressure in childhood (in combination with other risk factors) causes target organ and anatomical changes that are associated with cardiovascular risk, including reduction in artery elasticity. High blood pressure in children is strongly associated with obesity,

12 Most chronic diseases are present at later period of life - the result of interactions between multiple disease processes as well as more general losses in physiological functions (due to risk factors) = lack of oxygen and adapted metabolism.

13 Angiogenesis Angiogenesis is a process of new blood vessel growth that occurs in the human body at specific times in development and growth. Although crucial for embryonic development and wound healing, angiogenesis also contributes to disease, such as in the growth of solid tumors, chronic inflammation, atherosclerosis, ischemia, and diabetic retinopathy.

14 Inducers A number of inducers of angiogenesis have been identified, there is an emerging concept that reactive oxygen species (ROS such as ) superoxide anion O2- hydroxyl radical (OH-), lipid radical (LOO-), peroxy radicals (XOO-) and singlet oxygen (O-). Free radicals ROS are products of mitochondrial respiration (energy production).

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17 Dietary sources of ROS High fat diet and deep fries
High sucrose (or refined carbohydrates )diet Protein + sugar in high temperature (glycation) Low fruit and veg. diet Low vitamin and mineral diet (antioxidant). Life style: stress, pollution, smoking and low activity.

18 Golden rule More free radicals = chronic diseases = faster aging.
Less free radicals = healthier body.

19 How to slow down generation of Free radicals?
Homework.

20 Comparison B A Distance: 10,000 km Distance: 200, 000 km
Fuel consumption: 50,000 liter Distance: 200, 000 km Fuel consumption: 1000,000 liter Waste? Maintenance? Type of fuel?

21 The challenges for nutrition in the twenty-first century
1. Application of new scientific knowledge in nutrition. 2. Improved scientific knowledge on diet–disease relationships. 3. Exponential increase of health-care costs. 4. Increase in life expectancy. 5. Consumer awareness of nutrition and health relationships. 6. Progress in food technology.

22 Functional foods Japan:
History Japan: : economical food with minimal nutrients. : safe and hygienic food with better taste. : convenient food. Easy or precooked food. 1980- :Food for specific health use (foshu). :Functional food. (project)

23 The project also proposed for the first time the new concept of “functional food” and defined food functions as primary (nutritional), secondary (sensory) and tertiary (physiological). Food with physiological functions was of particular interest, because such food would be useful for improving the health of the general public

24 Definition no simple, universally accepted definition of functional food exists. Examples food and drink products derived from naturally occurring substances consumed as part of the daily diet and possessing particular physiological benefits when ingested. food derived from naturally occurring substances that can and should be consumed as part of the daily diet and that serve to regulate or otherwise affect a particular body process when ingested. food similar in appearance to conventional food, which is consumed as part of a usual diet and has demonstrated physiological benefit and/or reduces the risk of chronic disease beyond basic nutritional functions.

25 The main aspects of this working definition are:
the food nature of functional food that is not a pill, a capsule or any form of dietary supplement; the demonstration of the effects to the satisfaction of the scientific community; the beneficial effects on body functions, beyond adequate nutritional effects, that are relevant to improved state of health and well-being and/or reduction of risk (not prevention) of disease; the consumption as part of a normal food pattern.

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28 F F Science By reference to the new concepts in nutrition outlined above, it is the role of functional food science to stimulate research and development of functional foods

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30 Claim= promise of improvement
“Disease reduction claims” meaning: consumers have difficulties to differentiate between the terms ‘disease risk reduction’ and ‘prevention of diseases’.

31 How to write a claim

32 EFFECT OF FOOD PROCESSING ON FUNCTIONALITY OF FOODS
In foods containing vastly different phytochemicals, the physiological activity due to food processing may be a result of more than one mechanism. Consequently, there may be a decrease, increase, or a slight change in the content and functionality of phytochemicals. No/slight effect: carotenoids comprising of b-carotene and lycopene are generally stable to heat treatments encountered in blanching, cooking, and pasteurization/sterilization. Interactions between polyphenols and ascorbic acid may slow the degradation of the latter during storage.

33 Decrease in content and activity of phytochemicals:
a classic example is that of the “technological indicator,” ascorbic acid, which is by far the most sensitive nutrient, and can be damaged during most treatments. Chemical and/or enzymatic oxidations are reported to decrease the antioxidant efficacy of polyphenolics, while leaching into the cooking water is mainly responsible for loss of folates.

34 Heat processing of Brassica vegetables of the Cruciferae family greatly reduces their functionality . Manufacture of black tea causes a higher degree of enzymatic aerobic oxidation of flavonoids, resulting in lower antioxidant activity. Some processing operations such as peeling and juice clarification can remove the polyphenolics .

35 Increase in content and activity of phytochemicals:
partially oxidized polyphenolics that result during food processing, have been recently shown to exhibit higher antioxidant activity than the corresponding non-oxidized forms, due to increased ability to donate a hydrogen atom A moderate increase in carotenoid bioavailability and enhanced phytochemical nutrient function in cereal processing

36 Examples of functional ingredients
Vitamin antioxidant & mineral premixes; tomato powder, garlic powder, onion powder, spice mixes; amino acids, chitosan; Omega-3-fatty acids (fish and flax seed); whey protein powder; Guarana extract, G. biloba extract, ginseng extract, rosemary probiotics; natural antioxidants (from tea); “shield” liquid antioxidants; vegetable peptones;

37 essential fatty acids concentrates; performance proteins; natural fruit based flowering compounds; natural colours; total extracts of medicinal plants “antioxidants” soy ingredient, soy proteins, soy protein hydrolysate; soya protein isolate & concentrate; super critical extracts of spices; and herbs; glutamine peptides; lactoferrin, milk calcium; lycopene, garcinia, raw herbs; whey protein concentrate; wheat fiber, b-carotene; A. vera gel powder.

38 Risk factor or state Design a Functional Food CVD osteoporosis diabetes Irritable bowl syndrome (IBD) Pregnant woman

39 OXIDATIVE STRESS AND ROS
Oxidative stress = rusting of tissues. Oxidative stress is imposed on the body ’ s cells when the level of ROS outweighs the reducing capacity of antioxidant and antioxidative stress mechanisms ROS

40 Sources of ROS Endogenous sources of ROS tissue injury
via auto - oxidation reactions in the presence of transition metal ions. Fe 2 + or Cu + during cytochrome P450 cycling. at inflammatory sites by activated and phagocytes.

41 Exogenous sources of ROS
Exposure to ultraviolet (UV) radiation. Overexercise. Extrinsic xenobiotics found in tobacco smoke. Heavy metals. Organic pesticides. Lipid hydroperoxides in particular are potentially toxic products of peroxidized polyunsaturated fatty acids (PUFAs) derived from dietary fats. Compounds present in foods such as transition metal ions, heme from meats, isoprostanes, additives, lipids,

42 tripeptide of γ – glutamylcysteinylglycine.
DEFENSE SYSTEMS Endogenous antioxidants and antioxidative defenses Glutathione ( GSH ): tripeptide of γ – glutamylcysteinylglycine. directly scavenge free radicals or act as a substrate. GSH present in foods and secreted in the bile can contribute to GSH concentrations in the intestinal lumen.

43 Antioxidative stress enzymes:
glutathione peroxidase (GPx). glutathione S -transferase ( GST ). Catalase Additional antioxidants: uric acid. bilirubin - bound albumin, and albumin itself. Histidine - containing peptides such as carnosine. Melatonin. Amino acids, peptides, and even proteins. Se, Zn, Cu, Mn and riboflavin can all have co-factor functions for one of the above enzymes.

44 Phytochemicals with antioxidant activities
Polyphenols: 5000 polyphenols and over 2000 flavonoids having been identified. Phenolic acids, Flavonoids, Lignans

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48 Amides strong antioxidants: capsaicinoids in chili peppers. Carotenoids Lycopene, β – carotene, xanthophylls such as zeaxanthin.

49 Mechanism of action direct radical scavenging;
(2) downregulation of radical production; (3) elimination of radical precursors; (4) metal chelation; (5) Inhibition of xanthine oxidase; (6) elevation of endogenous antioxidants. Curcumin and flavonoids have been shown to upregulate intracellular GSH synthesis and increase antioxidant enzyme activities

50 METABOLISM AND BIOAVAILABILITY OF FLAVONOIDS
The extent of absorption of dietary polyphenols in the small intestine is relatively small. Bacterial enzymes may catalyze several reactions. Anthocyanins were found in the cerebellum, cortex, hippocampus. = important for learning and memory.

51 Antioxidant and C D CVD Antioxidant prevent LL oxidation. Cancer
Block activation to carcinogens. DNA repair. Inhibit the formation and growth of tumors.

52 Dietary Fiber Dietary fiber (DF) has been consumed for centuries and most food labels in the supermarket now list dietary fiber. Even though fiber is not considered a nutrient, health professionals and nutritionists agree that fiber is required in sufficient amounts for the proper functioning of the gastrointestinal tract.

53 Definition DF is the edible parts of plants or analogous carbohydrates that are resistant to digestion and absorption in the human small intestine with complete or partial fermentation in the large intestine.

54 Why ? DF consumption has established the basis for associating high-fiber diets in epidemiological studies with reduced risk of most of the major dietary problems in the U.S.A.; namely, obesity, coronary disease, diabetes, gastrointestinal disorders, including constipation, inflammatory bowel diseases. Chronic diseases

55 Classification Of Dietary Fiber
dietary fiber has been to differentiate dietary components on their solubility in a buffer at a defined pH, and/or their fermentability in an in vitro system using an aqueous enzyme solution representative of human alimentary enzymes.

56 Solubility Soluble fiber dissolves in water
This includes gums, mucilages, pectin and some hemicelluloses. found in all types of peas and beans like lentils, split peas, pinto beans, black beans, kidney beans, garbanzo beans, and lima beans, as well as oats, barley, and some fruits and vegetables like apples, oranges, and carrots.

57 Benefits For people with diabetes, eating foods that contain soluble fiber can help control or lower the level of sugar in their blood and decrease insulin needs It may also help lower blood cholesterol levels, especially LDL-cholesterol or the “bad” cholesterol.

58 Insoluble fiber does not dissolve in water.
Whole grains, wheat and corn fiber, and many vegetables like cauliflower, green beans, and whole potatoes are good sources of insoluble fiber. aids digestion by trapping water in the colon. helps prevent two kinds of intestinal diseases, diverticulosis and hemorrhoids.

59 Fermentability Fibers that are well fermented include pectin, guar gum, acacia (gum arabic), inulin, polydextrose, and oligosaccharides. Generally, well fermented fibers are soluble in water, while partially or poorly fermented fibers are insoluble.

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62 Physiological Effects of D fiber
major physiological effects of dietary fiber originate from the interactions with colonic content throughout its fermentation. It influences several metabolic processes, including the absorption of nutrients, carbohydrate and fat metabolism, and cholesterol metabolism.

63 influences the colonic structure and barrier function, and as the large intestine encompasses a significant body of the human immune system. Some form gels (pectins), while others have a high water holding capacity (WHC). its ability to adsorb or bind bile acids; and its fermentability by microorganisms in the gut.

64 Colonic Fermentation And Its Consequences
The large intestine is the most heavily colonized region of the digestive tract, with up to anaerobic bacteria /gram. end products produced from the fermentation, including gases (methane, hydrogen, carbon dioxide), short chain fatty acids (SCFA). Increases in microbial mass from fiber fermentation contribute directly to stool bulk

65 Gas production from colonic fermentation can also have some influence on stool bulk.
Poorly fermented cellulose produces very little acid during its fermentation, most of which is only acetic acid; by contrast, in the case of more fermentable fibers, large quantities of SCFA are formed. The metabolic end products of fermentation including the gases, SCFA, and increased microbiota, play a pivotal role in the physiological effects of fiber and implications for local effects in the colon and systemic effects

66 PHYSIOLOGICAL FUNCTIONS OF DIETARY FIBER
Dietary Fiber And Cancer Colon cancer is one of the leading causes of cancer morbidity and mortality among both men and women in the Western countries, including the U.S.A. Dietary Fiber And Carbohydrate Metabolism An association between insufficient dietary fiber intake and increased risk of diabetes has been postulated since 1970s.

67 Dietary Fiber, Lipid Metabolism, And Cardiovascular Disease
bind bile acids increasing their excretion and decrease cholesterol in the liver. SCFA are absorbed from the colon to the liver. Dietary Fiber, Mineral Bioavailability And Bone Health. certain highly fermentable fibers have resulted in improved metabolic absorption of certain minerals, such as calcium, magnesium, and iron,

68 Dietary Fiber, Role In Gut Barrier Function And Gastrointestinal Disorders.
SCFA stimulating repair in a damaged colon. barrier to prevent foreign materials from dietary or microbial origin from crossing into the internal body cavity. Prevent Intestinal permeability or “leaky gut syndrome’.

69 Probiotics Intestinal tract is home to one hundred trillion (1014) microorganisms. called the intestinal microflora. over 400 different species of microbes. The 400 species of microbes living in your body are fighting for space. They want to live, thrive and reproduce in your intestinal tract, an environment that offers the ideal temperature, humidity and food sources.

70 Depending on the type of bacteria, there is a different effect on the body; bacteria can have healthy, e.g., immune-boosting benefits or cause harm to the body. A careful balance is necessary for health.

71 Bad microbes live in your intestines and normally do not cause any disease-like symptoms.
Bad microbes flourish in an alkaline environment. Opportunistic and neutral = the majority. Good microbes found in the body, called probiotics. Probiotics have a positive impact on the body’s health. They prefer a more acidic intestinal environment. Many of the probiotics are called lactic acid bacteria.

72 They define the term probiotic as:
live microorganisms which when administered in adequate amounts confer a health benefit on the host. How do they work? What are these health benefits? How can we get them? What species can provide them? What’s the relationship with Chronic diseases? How can we maintain them?

73 Some history Pasture 1880, Eli Metchnikoff 1908, Tisser 1900,
W W I Nissil Southeast Asia, Boulardi. Cholera. 1950, group of scientists, found out that mice that were given oral antibiotics, which kill all bacteria, including probiotics, were more susceptible to infection.

74 Yakult Company of Japan in the 1930s
Yakult Company of Japan in the 1930s. Yakult Company introduced a fermented milk product that contained a probiotic culture. The term probiotic was not actually coined until the 1960s. In 1978, Dr. Tomotari Mitsuoka, illustrated how the composition of intestinal flora changes during a lifetime. Probiotics decrease with aging. WHY?

75 How Do Probiotics Work? The intestinal microflora has the metabolic activity potential equal to that of the liver, the most active organ in the body! The exact mechanisms of action by which probiotics elicit their beneficial effects are not fully understood.

76 Suggested mechanisms Probiotics Compete for Receptor Sites:
Intestinal wall

77 Change secretion to mask receptors:
Intestinal wall mucus

78 Probiotics Affect the Immune System:
Gastrointestinal tract is equipped with effective immune system, the most number of lymphoid is around the gut. Immune system is the key element of what to enter your body or not to. By producing antibodies these are messengers for all tissues connected with immune system. Probiotics supplementation is useful in a wide variety of immune-based ailments including allergies, asthma, eczema and irritable bowel disease.

79 probiotics help balance good and bad messengers of the immune system by keeping the system in check.
The result is healthy immune reactions and a healthier you. A careful balance of inflammation is required in the intestinal tract. Too much of an immune reaction can result in inflammation and damage to the intestines reducing their ability to digest and absorb nutrients = I B D.

80 Too little immune reaction allows pathogens to grow in the intestines, causing infectious diarrhea, which can develop into a chronic illness such as allergies. All in all, it appears that probiotics: reduce allergic reactions improve overall immunity promote proper immune reactions against pathogens.

81 Probiotics Consume Available Nutrients
There are lots of nutrients available in the digestive tract that support the needs of lactic acid bacteria to grow. By consuming a large portion of the available nutrients suitable for microbes, lactic acid bacteria restrains the growth of bad microbes. Probiotics Create an Acidic Environment Many bad microbes do not like a low pH.

82 Probiotics Produce Beneficial Enzymes
The enzyme activity of probiotics has been found to help fight infectious disease, lactose intolerance, immune system deficiencies, and urogenital and vaginal diseases. Probiotics Produce Antimicrobial Effects Many of the probiotic strains of bacteria are able to produce substances that kill bacteria, called bacteriocins

83 Probiotics Support Gut Barrier
Lactobacilli and Bifidobacteria produce fats that encourage the growth of cells that line the intestinal tract. These fats are called short chain fatty acids. These fats also have nutritional effects on the intestinal cells, keeping them well nourished and healthy. = Gut integrity.

84 Probiotics Encourage Healthy Microflora
In clinical trials, the use of combinations of probiotic species has been found to offer greater health benefits than any one of the probiotic species alone. Example; Lactobacillus reuteri produces protein to enhance the growth of other lactobacilli.

85 Manufacture of Probiotic Bacteria
Lactic acid bacteria (LAB) have been used for many years as natural biopreservatives in fermented foods. Dried concentrated probiotic cultures are the most convenient form for incorporation into functional foods, given the ease of storage, handling and transport, especially for shelf-stable functional products.

86 Probiotics are the main bioactive component of these fermented FF and numerous economic indicators show that probiotic-enriched products are still on the forefront of innovation in the FF sector: The probiotic yogurt market in Latin America grew 32% annually from 2005 to 2007 In the overall USA FF market, in 2004, fresh dairy products grew by 9–10% compared to 2% for cheese. The European food and beverage probiotics is expected to rise from its 2006 position of 62 million $ to 163 million $ by 2013

87 Selection of Strains the microbes should have GRAS (Generally Regarded As Safe) status, have a long history of safe use in foods, be non-pathogenic acid and bile tolerant should be viable (debatable). the bacteria should tolerate different technological stresses, such as acid, osmotic, cold, heat and drying stress.

88 Selecting the appropriate strain for a particular food can be divided in four categories:
Performance in the gastrointestinal tract (GIT) Industrial production. Safety of the microorganisms. Health benefit.

89 Question: Who do you think the most group of people in the community need functional foods, and Why?

90 Potential Protective Effects of Probiotics Against Colorectal Cancer
Colorectal cancer (CRC) is the fourth most frequent cause of cancer related mortality in the world. Approximately 944,000 new cases were diagnosed globally in 2000 and this accounts for 9.2% of all new cancer cases. the developed world suffering the highest rates and India one of the lowest

91 Evidence suggests that diet plays an important role in the aetiology of colorectal cancer.
associations between overweight/ obesity (waist circumference), processed meat, alcohol and increased risk of colorectal cancer. Fiber, garlic, milk and calcium are associated with decreased risk.

92 Colon Carcinogenesis involves inactivation of various tumor suppressing genes. activation of mutations. loss of function in DNA repair genes Metabolic activity of microflora.

93 Role of the Gut Flora in Cancer
Once the microbiota is established, little qualitative variation in the composition occurs over time, although there is extensive evidence that the metabolic activity of the microbiota can be modulated by diet. Evidence from a wide range of sources supports the view that colonic microbiota is involved in the aetiology of cancer.

94 The main pieces of evidence are:
Human feces have been shown to be mutagenic and exert tumor promoting activity in vitro and genotoxic substances of bacterial origin have been isolated. 2. Intestinal bacteria can produce, from dietary components, substances with genotoxic, carcinogenic and tumor-promoting activity. 3. Gut bacteria can activate procarcinogens to DNA reactive agents.

95 4. Germ-free rats treated with the carcinogen 1,2-dimethylhydrazine have a lower incidence of colon tumors than similarly treated rats having a normal microbiota. 5. Germ-free rats fed human diets exhibit lower levels of DNA defect in tissues than conventional rats.

96 Evidence that probiotics can influence carcinogenesis is derived from a variety of sources:
1. Effects on bacterial enzyme activities. 2. Antigenotoxic effects in vitro and in vivo. 3. Effects on pre-cancerous lesions in laboratory animals. 4. Effects on tumor incidence in laboratory animals. 5. Epidemiological and experimental studies in humans.

97 Examples: metabolism of the primary bile acids to secondary acids, which are thought to possess tumor-promoting activity. nitrite can be converted to N-nitroso compounds (mutagenic) by bacteria under neutral pH. In a conventional rat study, supplementation of a high meat diet (72% beef) with L. acidophilus (109–1010 organisms/day) significantly decreased by 40–50% the activity of fecal b-glucuronidase and nitroreductase

98 consuming milk supplemented with 109 viable lactobacilli per day decreased activity of feacal enzymes. LAB was able to bind the mutagens in vitro. Production of SCFA, Acetate is the major SCFA found in human feces. In the host, it may be absorbed and utilized by peripheral tissues SCFA, in particular butyrate, are potential anti-carcinogenic.

99 Apoptosis: or programmed cell death is one of the primary mechanisms by which multi-cellular organisms control normal development. In cancer it is out of control. Probiotics are able to balance apoptosis.

100 First Exam

101 Prebiotics Coined by G. Gibson, “non-viable food component that beneficially affect the host by selectively stimulating the growth and/or activities of one or a limited number of bacteria in the colon,” Prebiotics allow the selective growth of certain indigenous gut bacteria. such as bifidobacteria and lactobacilli which are already resident in the human colon

102 To be an effective prebiotic a colonic food must:
neither be hydrolysed nor absorbed in the upper part of the gastrointestinal tract. have a selective fermentation such that the composition of the large intestinal microbiota is altered towards a healthier composition.

103 Commercially available prebiotics
fructose-containing oligosaccharides (FOSs). these prebiotics are the European market leaders. Bifidobacteria are able to breakdown and utilise fructo-oligosaccharides due to their possession of the ß- fructofuranosidase enzyme. FOSs have proven prebiotic effects in human trials

104 Galacto-oligosaccharides (GOSs) are another class of prebiotics that are manufactured and marketed in Europe as well as Japan. They have found application in infant formula foods as they are naturally present (low quantity) in human milk. Gluco-oligosaccharides can also act as prebiotics. or Isomalto-oligosaccharides (IMOs). Slowly metabolized and pass to colon.

105 Xylo-oligosaccharides (XOSs) are also used as prebiotics in Japan
XOS are much more acid stable than other prebiotics. For this reason, they have found application in soft drinks which tend to be acidic. Lactulose.

106 Are Dietary Fibres prebiotics?
Dietary fibres (e.g. from wheat, maize, rice, soya) have always been considered to have a beneficial effect on gut function and colonic bacteria, but this is a generalised stimulatory effect and such polysaccharides are not selectively fermented in the colon.

107 Mechanisms of Prebiotic Impact on Health
Local and Physiological Effects of Prebiotics Mucosal Structure 1) increase in numbers of epithelial cells, and the intensities of their secretory functions. 2) enlarged the available area of nutrient absorption possibly SCFA are responsible for these adaptive changes.

108 Intestinal Mucus Made of mucin produced by goblet cells lining the gut. Act as barrier. Mucus is a source of nitrogen and carbon for bacteria; its continuous production by the host makes the gut good environment for microorganisms, 1) Administration of dietary prebiotics appears to thicken the mucus layer and increase its secretion by goblet cells

109 Mineral Bioavailability
there is a strong inverse relationship between the amount of phytic acid in the diet and iron Ca, and Zn absorption. 1) prebiotics are known to have stimulatory effects on iron absorption in the large bowel. 2) Addition of FOS to the diet restores zinc absorption by enhancing zinc bioavailability 3) prebiotic consumption is associated with enhanced breakdown of phytic acid (60%), low pH decrease its solubility

110 Undigested Food (prebiotic)
Colonic environment Zn SCFA Phytic acid Undigested Food (prebiotic) Ca Phytase enzyme Fe hydrolysis fermentation Probiotic bacteria Ca Zn Fe pH Mineral Solubility

111 Modulation of the Gut Microbiota
In chronic diseases and Gastrointestinal tract diseases it was found that decreased levels of bifidobacteria and lactobacilli are associated with the problem. 1) Prebiotic can increase these levels and prevent from C D.

112 Immune System prebiotics, may be particularly useful in inflammatory conditions, or in children and the elderly. FOS and lactulose to the diet has been shown to increase : 1) mucosal immunoglobulin production. 2) lymph nodes number. 3) altered pro-inflammatory compounds in the spleen and intestinal mucosa.

113 Lipid Metabolism Human studies have been small in scope, focused on the relationship between the intake of prebiotics and serum lipid levels. The results have been inconsistent, and any mechanisms of action unclear. Animal studies showed lowering effect of prebiotics on LDL and cholesterol (especially when fed high fat meal) May be due to interference with hepatic lipogenesis.

114 General Mechanism

115 Prebiotics Applications
Infants Oligosaccharides are prebiotic factors in human milk, causing increased levels of bifidobacteria in breast-fed babies compared to bottle-fed infants. Prebiotics have been used in infant formulas in Japan over the last 2 decades, and in Europe for the last 5 years. addition of 0.8 g/dl of a mixture of 10% short chain FOS and 90% long chain infant formulas was safe to add to infant formula.

116 Atopic Disease (allergy).
Allergic disease in infants is based on imbalanced response to food allergen and lower numbers of bifidobacteria are found in allergic infant feces. By increasing the number of bifidobacteria prebiotics rebalance the immune response. Prebiotic feeding studies in allergic infants have demonstrated significant reductions in the incidence of atopic dermatitis, and this was associated with increased numbers of fecal bifidobacteria.

117 Enterocolitis In premature infants, bifidobacterial colonization is delayed in favor of high levels of enterobacteria and clostridia= enterocolitis. Breast-feeding has always been thought to protect against enterocolitis. No human studies using prebiotics alone.

118 Infection Prevention Studies in children aimed at prevention of infection have also had mixed results. The addition of 1.1 g of oligofructose daily to cereal of 123 infants (4–24 months) was associated with reduced episodes of fever and medical visits. The control group had more sick days, and a higher intake of antibiotics.

119 134 infants fed prebiotics (8 g/l GOS/FOS) for the first 6 months of life, principally looking at allergic disease, the subjects were followed up until they were 2 years of age. fewer episodes of physician diagnosed infections , fewer episodes of fever and fewer antibiotic prescriptions.

120 2. Gastrointestinal Effects
Irritable bowel syndrome (IBS) has been linked to intestinal bacteria in a number of different trials. IBS is a difficult disease to investigate, because the symptoms are highly subjective and difficult to quantify. Gas production discomfort and flatulence are some of the symptoms associated with IBS. many patients have visceral hypersensitivity, so prebiotic fermentation and gas production may exacerbate their symptoms, and have adverse affects on health and wellbeing.

121 Constipation Prebiotics may have Laxative effects. May be due to gas production and increased microbial mass. There is a good relation between intestinal motility and bacterial composition. With the exception of lactulose, the prebiotics studied so far in human trials have been shown to have little effect on managing constipation, and to have only mildly laxative properties.

122 Diarrhea & Antibiotic-Associated Diarrhea.
traveler’s diarrhea (E. coli) , frequency of diarrhea in the prebiotic group (11.2%), compared to the placebos (19.5%). Clostridium difficile infections are antibiotic-associated diarrhea (AAD). Diarrhea associated with Clostridium difficile is a leading cause of hospital outbreaks of diarrhea and it considerably increases mortality and healthcare costs. Prebiotics reduce episodes of AAD and C. difficile diarrhea relapse.

123 3. The Elderly As people get older they often have a greater susceptibility to diseases and suffer from an increase in gastrointestinal infections, malnutrition, constipation and diarrhea. decrease in immune function and a reduction in numbers of beneficial bacteria such as bifidobacteria, along with an increase in potentially harmful microrganisms. few studies on the use of prebiotics in the elderly.

124 4. Other Areas. Diabetes Because prebiotics are non-digestible low energy bulking ingredients this makes them beneficial they in diabetic control. The proposed mechanisms of action in diabetic disease involve SCFA. Since High concentrations of free fatty acids (mainly from food) in plasma lower the use of glucose in tissues, and induce insulin resistance.

125 Rheumatoid Arthritis. In animal studies prebiotics showed ability to decrease pro-inflammatory compounds by modulating the gut microbiota. Obesity Prebiotics are excellent potential to act as substitutes for sucrose, and to be used as sweeteners. GOS are stable at high temperatures and low metabolic value at 1.73 kcal/g, while FOS are similar at 1.5 kcal/g.

126 they promoted satiety, and reduced food intake.

127 Resistant Starches Resistant starches are defined as the sum of starch and products of starch degradation not absorbed in the small intestine of healthy individuals. There are four main groups of resistant starches: RS1- RS4. RS1 is physically inaccessible starch (i.e., starch in whole grains), RS2 is granular starch i.e., starch in green bananas), RS3 is retrograded starch (i.e., starch in cooked and cooled potatoes) and RS4 is a chemically-modified starch (i.e., an esterified starch).

128 RS has a calorific value of 1.70 kcal/g.
The glycemic response for RS is approximately 10% that of a maltodextrin control. Type 3 RS was shown to be well tolerated up to doses as high as 45 g/d.

129 Applications Applications for RS include puffed or sheeted snacks, chips, extruded breakfast cereals, pasta, muffins, cookies and biscuits, crackers, frozen dough, breads. it can also be used in low calorie products reducing both calories and carbohydrates when replacing flour or other cereal-based ingredients. Due to its low water holding property, it also does not affect height and spread management of biscuits, cookies or other baked goods.

130 RS enhances crispiness of cookies and crackers.
In fried snacks, fat uptake may be reduced by up to 25% when RS is used, helping to meet ‘‘high/rich in fiber’’ claims. RS3 thermal stable as high as 150⁰ C, it will retain more fiber content and structure than other resistant starches, which start to breakdown below 120⁰ C. RS act as prebiotics in the gut. Sugar derived from RS can be used as sweeteners.

131 Functional foods in Palestine, What do we need to know?
Workshop design Functional foods in Palestine, What do we need to know?

132 Garlic and Onion as Functional Foods
Historically garlic and onion were used to preserve food from microbial spoilage. Garlic has been eaten more than 4000 years and onion was cultivated in middle east before 5000 years. They were used for their medicinal properties. Garlic on the top of vegetable-pyramid representing potency in cancer prevention (NIC).

133 GENERAL COMPOSITION AND SULFUR COMPOUNDS OF GARLIC AND ONION

134

135 The general composition is, of course, important to the nourishment of both garlic or onion eaters, however, in respect to the food function, the extraordinary high content of sulfur compounds in these vegetables should be much more important. These compounds are present as a group of sulfur-containing amino acids. When injured or damaged by slicing, the sulfur-containing amino acids in these plants are transformed immediately into volatile organosulfur compounds.

136 These compounds are called Alliins.
Alliin is degraded by alliinase into pyruvic acid and ammonia. Alliinase is heat labile, and irreversibly inactivated at pH 3.8 or lower. Oxidation of Alliins produces Allicin which has bactericidal and fungicidal effect. = in water it is active up to 40 days. = at -70⁰C up to 2 years.

137 Organoselenium Compounds in Garlic and Onion.
Allium plants, especially garlic and onion, is their strong potential to uptake inorganic selenium, either selenate or selenite, from the soil or water culture medium, and synthesize organoselenium compounds. Se-containing peptides, has been determined, and from this peptide a potent agent for cancer prevention was derived.

138 PHYSIOLOGICAL AND NUTRITIONAL FUNCTIONS OF GARLIC AND ONION, AND THEIR HEALTH BENEFITS
Garlic and onion use sulfur compounds to protect themselves, Even in our bodies, sulfur-containing compounds play a defensive mechanism. Onion has a lesser amount of sulfur compounds as compared with garlic. However, because people consume onion much more than garlic, the amount of sulfur compounds taken from onion per person may be comparable to or more than that from garlic.

139 Antibiotic Effect. growth inhibition by an aqueous garlic extract. Which was diluted 100 times with water (about 10 ng/ml allicin) showed a clear inhibition zone, and some fungus did not grow inside of the zone for up to 7 days. Alkyl thiosulfinates are recognized as the most effective compounds exhibiting antimicrobial activity.

140 Antithrombotic Effect.
Suppression of platelet aggregation is the most beneficial effect of garlic intake. vascular dilation have been observed primarily with garlic oil in human and animal studies. Thus, garlic may prevent thrombus formation through many mechanisms involving antithrombotic, vasodilative effects.

141 Lipid-Lowering Effect.
several garlic compounds have been reported to be effective. The lipid-lowering effects appear to be due to their degradation products, those that may be produced from the compounds soon after the absorption from the intestine. And from the reduced gene expression may be an important factor in the lipid-lowering effects of garlic.

142 Hypoglycemic Effects. It has been proposed that garlic compounds stimulate insulin production and prolong insulin turnover. Especially, sulfur compounds from garlic were considered to protect insulin from its inactivation. alliin (200 mg/kg) is known to reduce the plasma glucose level in diabetics.

143 ANTICANCER EFFECTS OF GARLIC AND ONION
A number of epidemiological and experimental studies indicated that garlic and onion can be considered as important functional foods for cancer prevention. study in northeast China found that the consumption of onion was inversely related to the risk of developing brain cancer. Similar studies reported that garlic intake significantly reduced the risk of prostate and breast cancers, and increased protective power against stomach and colorectal cancers.

144 3. Site-specific case-control studies on stomach and colorectal cancers suggest a protective effect of high intake of raw and/or cooked garlic. 4. The overall anticancer effects that have been reported for garlic and onion by some hundreds of researchers can be collected largely into three groups: Antimutagenic and anticarcinogenic effects. Antiproliferative effects. Differentiation effects involving the apoptotic effect.

145 Other Effects. blood pressure-lowering. Diuretic. anti-inflammatory, immunomodulatory. Enhancing effect on vitamin B1 absorption. stimulate both noradrenaline secretion from nervous systems and testosterone from testis.

146 Garlic processing Cutting, slicing, crushing.
Allicin from damaged garlic turned to sulfides. Allicin may collected when slicing garlic in water, but sulfides better collected in cooking oil. Boiling and heating If an intact bulb is heated, alliin stays unchanged inside the bulb. if the heating is not quite sufficient to denature the alliinase, a large amount of alliin is transformed into allicin and sulfides while cooking or eating the bulb.

147 Heating the chopped garlic in cooking oils, allicin, sulfides as well as alliin must be present, in the oils or within the pieces. Hence, people prefer to cook garlic with cooking oils or fatty meats. Pickling The pickled clove in any medium loses alliinase activity more or less, depending on the period of its preservation. It takes at least a month to penetrate a medium into the clove with a gradual decrease in alliinase activity.

148 Garlic Oil Garlic Powder Dehydrated Onion Pieces Onion Powder Onion Oil Onion Salt Pickled Onion

149

150 Quiz Discuss briefly how probiotics and /or prebiotics may prevent from cancer?

151 Green and Black Tea Tea (Camellia sinensis) has been discovered and utilized for its unique flavor and medicinal properties by man for a long time, which may be traced back to 5000–6000 years ago in China. Tea beverages are now the second most popular drinks and only next to water in terms of worldwide consumption. Scientific research on the chemical components and functionalities of tea is relatively recent.

152 Through research, tea has been linked with health benefits including protection of oxidative DNA damage, lowering the atherosclerotic index and improving blood flow, liver function, and oral health. Nowadays, the utilization of tea has been extended not only to pharmaceutical products but also to toiletry, cosmetic, and food products.

153 Commercial tea leaf products can be classified into three major types: green tea, black tea, and oolong tea. Green tea is nonfermented processed tea, in which polyphenols in fresh tea leaves are less oxidized. Black tea and oolong tea are enzymatically fermented tea, with black tea being the most fermented and oolong tea partially fermented (or so called semifermented).

154 Tea polyphenols The functional properties of tea are believed to be due to tea polyphenols. The principal tea polyphenols are tea catechins. Catechin has been accepted as a quality indicator of green tea products. There are some 8–30% of total catechins in dry green tea leaves. The estimated daily intake of tea catechins based on 3 cups (600 mL) of green tea (1– 4 g), which is brewed traditionally (1–5 min in boiling water), is in the range of 538–2594 mg of total catechins.

155 the antioxidative activity/free radical scavenging ability of tea catechin varies with the type of radical species, ionization state, pH, polarity, and enzyme in the designated studies.

156 GREEN TEA ANTIOXIDANTS AND HEALTH BENEFITS
Green Tea and Neurodegenerative Diseases Catechins chelate metal ions such as copper(II) and iron(III) to form inactive complexes and prevent the generation of potentially damaging free radicals. In the rat brain tissue, green tea and black tea extracts were shown to inhibit lipid peroxidation promoted by iron. As well decrease neurons death (Alzheimer's)

157 Green Tea and Obesity Polyphenols interact to alter the energy balance. the redox status or potential. the activities of obesity-related cells. Green Tea and Cardiovascular Disease. cardiovascular diseases is multifactorial and comprises processes, which appear to be affected by tea ingredients: endothelial dysfunction. inflammation. And • thrombus formation

158 Green Tea and Cancer inhibition of oxidative stress. inhibition of carcinogen. induction of apoptosis. Inhibition of angiogenesis. Type of cancers: Skin cancer: Studies have suggested that green tea polyphenols may afford protection against inflammatory responses and the risk of skin cancer.

159 Lung Cancer: Ingestion of green tea (2% of diet) decreased the number of lung induced tumors in mice. consumption of green tea was associated with a reduced risk of lung cancer among nonsmoking women and the risks decreased with increasing consumption. Liver Cancer: In a study in China it was found that Green tea drinking decreased the risk for the development of liver cancer by 78% among alcohol drinkers and 43% among cigarette smokers.

160 Breast Cancer: green tea consumption was associated with a reduction in breast cancer risk.
Prostrate Cancer: Green tea inhibits the growth and progression of prostate cancer in model mice. ANTIBACTERIAL AND ANTIVIRAL ACTIVITY: Antimicrobial activity against cariogenic and periodontal bacteria has been reported. Tea extracts inhibit enteric pathogens such as Staphylococcus aureus, Salmonella typhi, Shigella, V. cholerae, Cam. jejuni,

161 Tea polyphenols also inhibit bacteria responsible for tooth decay.
black and green tea extracts can kill Helicobacter pylori associated with gastric, peptic, and duodenal ulcer diseases. but are not effective against Escherichia coli, Pseudomonas aeruginosa. Some results indicate that tea catechins are potentially antiviral and antiprotozoiac agents

162 Polyphenols stability
The stability of tea catechins is dependent on pH and temperature. In acidic systems (pH < 4), tea catechins are fairly stable. in systems of pH > 5, that is, near neutral or alkaline systems, they degrade rapidly. On the contrary, tea catechins become less stable when processing temperature increases, where thermal degradation, oxidation could occur. 82°C was reported as a turning point in thermal reactions of tea catechins

163 Ascorbic acid showed a significantly protective effect on the stability of tea catechins.
Functional food containing Green tea. green tea beverage products. Sport beverages. cereal, confectionary, dairy, edible oil. ice cream and noodle products containing green tea. Green tea extracts have also been incorporated in chocolates and chewing gums.

164 Tea and iron Crit Rev Food Sci Nutr. 2000 Sep;40(5):371-98.
Effect of tea and other dietary factors on iron absorption. Zijp IM, Korver O, Tijburg LB. Source Unilever Research Vlaardingen, The Netherlands. Abstract Iron deficiency is a major world health problem, that is, to a great extent, caused by poor iron absorption from the diet. Several dietary factors can influence this absorption. Absorption enhancing factors are ascorbic acid and meat, fish and poultry; inhibiting factors are plant components in vegetables, tea and coffee (e.g., polyphenols, phytates), and calcium. After identifying these factors their individual impact on iron absorption is described. Specific attention was paid to the effects of tea on iron absorption. We propose a calculation model that predicts iron absorption from a meal. Using this model we calculated the iron absorption from daily menus with varying amounts of enhancers and inhibitors. From these calculations we conclude that the presence of sufficient amounts of iron absorption enhancers (ascorbic acid, meat, fish, poultry, as present in most industrialized countries) overcomes inhibition of iron absorption from even large amounts of tea. In individuals with low intakes of heme iron, low intakes of enhancing factors and/or high intakes of inhibitors, iron absorption may be an issue. Depletion of iron stores enhances iron absorption, but this effect is not adequate to compensate for the inhibition of iron absorption in such an inadequate dietary situation. For subjects at risk of iron deficiency, the following recommendations are made. Increase heme-iron intake (this form of dietary iron present in meat fish and poultry is hardly influenced by other dietary factors with respect to its absorption); increase meal-time ascorbic acid intake; fortify foods with iron. Recommendations with respect to tea consumption (when in a critical group) include: consume tea between meals instead of during the meal; simultaneously consume ascorbic acid and/or meat, fish and poultry. Send to: Display Settings: Abstract Tea and iron Crit Rev Food Sci Nutr Sep;40(5): Effect of tea and other dietary factors on iron absorption. Zijp IM, Korver O, Tijburg LB. Abstract Iron deficiency is a major world health problem, that is, to a great extent, caused by poor iron absorption from the diet. Several dietary factors can influence this absorption. Absorption enhancing factors are ascorbic acid and meat, fish and poultry; inhibiting factors are plant components in vegetables, tea and coffee (e.g., polyphenols, phytates), and calcium. For subjects at risk of iron deficiency, the following recommendations are made. Increase heme-iron intake (this form of dietary iron present in meat fish and poultry is hardly influenced by other dietary factors with respect to its absorption); increase meal-time ascorbic acid intake; fortify foods with iron. Recommendations with respect to tea consumption (when in a critical group) include: consume tea between meals instead of during the meal; simultaneously consume ascorbic acid and/or meat, fish and poultry.

165 Am J Clin Nutr Mar;73(3): Green tea or rosemary extract added to foods reduces nonheme-iron absorption. Samman S, Sandström B, Toft MB, Bukhave K, Jensen M, Sørensen SS, Hansen M. Abstract BACKGROUND: Phenolic compounds act as food antioxidants. One of the postulated mechanisms of action is chelation of prooxidant metals, such as iron. Although the antioxidative effect is desirable, this mechanism may impair the utilization of dietary iron. Results The presence of the phenolic-rich extracts resulted in decreased nonheme-iron absorption. Mean (+/-SD) iron absorption decreased from /- 4.5% to 8.9 +/- 5.2% (P < 0.01) in the presence of green tea extract and from 7.5 +/- 4.0% to 6.4 +/- 4.7% (P < 0.05) in the presence of rosemary extract. CONCLUSION: Phenolic-rich extracts used as antioxidants in foods reduce the utilization of dietary iron.

166 J Hum Nutr Diet. 2004 Feb;17(1):43-54.
Impact of tea drinking on iron status in the UK: a review. Nelson M, Poulter J. Abstract BACKGROUND: The aims of this review are (1) to evaluate the literature on the likely impact of tea drinking on the iron status of different groups within the UK population RESULTS: There is clear evidence to show that tea drinking limits the absorption of nonhaem iron. CONCLUSION: From the available evidence there is no need to advise any restriction on tea drinking in healthy people with no risk of iron deficiency. In groups at risk of iron deficiency the advice should be to drink tea between meals and to wait at least 1 h after eating before drinking tea.

167 What will happen to gut microflora if there is more iron in the gut?
Good bacteria don’t require iron for growth (this is the case in infants). Enterobacteria require iron for growth.

168 Am J Clin Nutr. 2010, 92(6): The effects of iron fortification on the gut microbiota in African children: a randomized controlled trial in Cote d'Ivoire. BACKGROUND: Iron is essential for the growth and virulence of many pathogenic enterobacteria, whereas beneficial barrier bacteria, such as lactobacilli, do not require iron. Thus, increasing colonic iron could select gut microbiota for humans that are unfavorable to the host. OBJECTIVE: The objective was to determine the effect of iron fortification on gut microbiota and gut inflammation in African children.

169 RESULTS: At baseline, there were greater numbers of fecal enterobacteria than of lactobacilli and bifidobacteria. There was a significant increase in the number of enterobacteria and a decrease in lactobacilli in the iron group after 6 mo. CONCLUSIONS: Anemic African children carry an unfavorable ratio of fecal enterobacteria to bifidobacteria and lactobacilli, which is increased by iron fortification. Thus, iron fortification in this population produces a potentially more pathogenic gut microbiota profile, and this profile is associated with increased gut inflammation.

170 Will the chelated iron by tea polyphenol affect gut microflora?
If you find the answer you get 5 marks

171 Sesame for Functional Foods
Sesamum indicum L., is believed to have originated in the Savanna of central Africa spreading to Egypt, India, the Middle East, China. Medicinal value and anti aging (seeds and oil). Despite such high values placed on sesame seed and oil, there have been few scientific studies to elucidate their functions.

172 Regarding the worldwide per capita consumption of sesame seed, South Korea is highest, at 6–7 g/day and Japan follows with about 2–3 g/day. The growth period for sesame usually ranges from 3 to 4 months but flowering begins as early as 30−40 days after sowing. Blooming continues until maturity, and the seeds scatter suddenly from the capsule, as illustrated by the magic words, “Open, sesame!” As a result, harvesting of sesame cannot be done mechanically but requires extensive manual labor.

173 SESAME SEED AS FOOD It contains much oil (about 50%), which is very stable against oxidative deterioration. about 20% protein plus various minor nutrients. The good flavor generated by roasting sesame seeds is also a highly desirable characteristic. used as a topping for many baked foods such as breads, biscuits, and crackers. sesame paste is generally used. For example, the paste is the base for much of the cooking (called tahina) and for cake (halva).

174 COMPOSITION OF SESAME SEED
OIL The average content of oil was 55% in white-seed strains and that of black-seed strains was 47.8%. Fatty acids in the oil are mainly oleic (18:1 = 39.1%) and linoleic (18:2 = 40.0%) acids. sesame oil in which n−3 fatty acid content is low so it will be inferior to soybean and corn oils.

175 PROTEIN. Sesame seed contains about 20% protein. the amino acid composition of sesame seed protein is slightly lower in lysine (31 mg/g protein), but higher in other amino acids, especially methionine (36 mg), cystine (25 mg), arginine (140 mg), and leucine (75 mg).

176 CARBOHYDRATE. The carbohydrate content in sesame seed is about 18–20 wt.% The presence of small amounts of glucose and fructose, and also an oligo sugars. no starch is present. Most carbohydrates seem to be present as dietary fibers, and the content of the dietary fibers has been reported to be 10.8%.

177 VITAMINS AND MINERALS sesame seed contains a significant amount of the vitamin B group. Since the vitamin B group is contained only in the coat or hull of the seed, it is necessary to use sesame fl our or paste of whole sesame seed for utilization of the vitamin B group in sesame seed. vitamin E is very interesting in relation to the effectiveness of sesame seed as a health food. sesame seed appears to contain very little vitamin E activity.

178 Functional composition
Lignan sesame seed contains significant amounts of lignans such as sesamin, sesamolin, sesaminol. sesame lignans are being noted as the most important and characteristic components of sesame seed in view of their various functional activities.

179 EFFECT OF SESAME SEED AND LIGNANS ON LIPID METABOLISM
1- CONTROLLING ACTION OF SESAME LIGNAN ON THE N−6/N−3 RATIO OF POLYUNSATURATED FATTY ACIDS The n−3 series polyunsaturated fatty acids in the diets are assumed to be related to the onset of such diseases as arteriosclerosis, cancer and allergy diseases, and the ingestion ratio of fatty acids of the n−6 series to those of the n−3 series is considered to be significant. it was found that sesame lignans have the ability to adjust the ratio of n−6/n−3 in the organism.

180 2- EFFECTS OF SESAMIN ON FATTY ACID OXIDATION AND SYNTHESIS.
the level of fatty acids in the liver was reduced by the intake of sesame lignans. the level of serum triglycerol Was reduced. Dietary sesamin increased the hepatic activities of fatty acid oxidation enzymes as well as the enzymes involved in β-oxidation of unsaturated fatty acids dose-dependently. Lower the lipogenic enzymes.

181 HYPOCHOLESTEROLEMIC ACTIVITY OF SESAME LIGNANS.
sesamin is effective in preventing cholesterol accumulation in the liver. sesamin has the effect of lowering serum cholesterol in rats independent of the addition of cholesterol into the diets. Lignans increased the concentration of total HDL, and they also effectively decreased serum VLDL. The lowering effect of sesamin on cholesterol concentration may occur mainly through inhibition of the absorption of cholesterol from the intestine.

182 ANTIHYPERTENSIVE ACTIVITY OF SESAMIN.
Results (mainly on rats) indicated that chronic ingestion of vitamin E and sesamin have adjusted elevation in blood pressure, oxidative stress, and thrombotic tendency, suggesting that these treatments might be beneficial in the prevention of hypertension and stroke. IMMUNOREGULATORY ACTIVITY. effects on the plasma levels of immunoglobulins.

183 PREVENTION OF CANCER. In the growth of breast cancer of rats, a significant suppressive effect was observed when fed a sesamin-containing diet (0.2%). The dietary lignans significantly decreased the incidence of colon cancer. Sesame oil decreased the side effect of drugs used by cancer patients.

184 HYPOGLYCEMIC ACTION OF SESAME
May be due to delay in glucose absorption. PREVENTION OF ALZHEIMER’S DISEASES Due to Anti oxidant activity. ANTITHROMBOSIS ACTIVITY. This activity was determined by the inhibitory effect on human blood platelet aggregation.


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