Dietary Fiber And Polyunsaturated FA Flashcards
Can fiber be digested by mammalian digestive enzymes
No
– but microbes in ruminants can break these down
What is the best method for detection of fiber?
Chemical
What are soluble fiber types? And what are their sources?
Pectin -fruit and veg
Gums -oat
Mucilages -legumes
Hemicelluloses -psyllium husks
What are insoluble fiber types?
Hemicelluloses
Cellulose
Modified cellulose
Lignin (woody plants)
Dietary fiber is broken down into short chain fatty acids and gas by???
Bacteria
What are the short chain fatty acids? Where are they used as an energy source?
Butyrate, propionate, and acetate
Cells lining the large intestine
Short chain fatty acids produce a _______ environment and promote water and electrolyte absorption
Acidic
Canine gets __________ % energy from short chain fatty acids
<10
What type of fibers are rapidly fermented?
Water soluble –> viscous gels
Readily fermented in large intestine
Bind minerals (cations)
Tend to bind digestive enzymes
Slow nutrient absorption
What are the slowly fermented fibers?
Insoluble in water (eg cellulose, soybean or peanut hulls)
Resistant to bacterial fermentation and do not bind digestive enzymes or minerals
Weight loss foods should contain (high or low) amounts of fiber?
High
Eg . Cellulose Guar gum Pectin Psyllium husks Beet pulp
What is a non-digestible food that benefits the host by selectively stimulating/inhibiting activity of bacteria
Prebiotics
What are dietary sources of prebiotics?
Soybean
Insulin
Raw oat
Unrefined wheat and barley uu
Fiber can be used therapeutically for what diseases?
Obesity Diabetes mellitus Hyperlipidemia Normalize intestinal motility Trichobezoars Colitis Constipation
When treating constipation with fiber you must ensure the patient is adequately ___________
Hydrated
T/F: crude fiber = total dietary fiber
True
What is thee difference between facilitative and functional lipids?
Facilitative
- palatability and texture
- dense calorie source, stored as energy
- promote fat soluble vitamin absorption
Functional
- cell regulation or metabolism
- esssential (linolenic acid, a-linolenic acid, arachidonic, eicosaphentanoic, and docosahezenoic)
A fatty acid with one double bond is called?
Monosaturated
A fatty acid with multiple double bonds is called?
Polyunsaturated
How do mammals synthesize fatty acids?
Glucose and/or amino acids -> acetyl CoA -> saturated fatty acids
Are enzymes for lipid biosynthesis more active when consuming at low fat diet OR when consuming high fat diets
Low fat diets (eg herbivores)
In a high fat diet (eg cats and dogs) fats are directly used and stored
Where do cats get arachadonic acids?
From spiders!! Jk
From animal tissues -> cats do not have the enzymes to synthesize
Linolenic acid can by synthesized into eicosapentaenoic acid and docosahexaenoic acid, if you supply linolenic acid will it be sufficient to supply EPA and DHA needs?
Only about 10% of linolenic acid is made into EPA
If you need EPA you should supply directly (kittens and puppies require this)
Fish oils
Linolenic acid if sound in _________________ that are extruded from epidermal keratinocytes
Phospholipid ceramides
What is the function of linolenic acid?
Enhance cell adhesion and make a water barrier to the epidermis
What is the function of alpha-linolenic acid ??
Contribute to water barrier
Sparing effect on linolenic acid
What is the function of arachidonic acid?
Is 20-25% of Fatty acid of cell membrane phospholipids of skin and tissues
Works in the COX pathway as a receptor for ecosanoids –> inflammatory process
What is a competitive substitute for arachidonic acid
Eicosapentaenoic acid
What are clinical signs of essential fatty acid deficiency?
Poor growth and weight gain
Cutaneous changes
Infertility and poor wound healing
T/F: n-3 PUFA are more effective in inhibiting n-6 PUFA metabolism than vice versa
True
What is a 20 carbon fatty acid that is synthesized locally in response to their immediate environment
Ecosanoids
What are products of cyclooxygenase?
Prostaglandins and thromboxanes
What are products of lipoxygenase
Leukotrienes
What are the potential clinical benefits of ecosanoids
Immune response-> regulated production and biological function of cytokines
N-3 PUFA generally reduced immune reactivity and are mediated through changes in eicosandoid production
What is a good source of n-3 and n-6 PUFA?
Supplant
Natural fish oil concentrate
Is flaxseed oil a good source of ecosanoids for cats?
Nope, cannot make flaxseed oil into n-3 therefore not a good source of ecosanoids
