Fiber Flashcards
soluble fibers
fructans, psyllium, beta-glucans, pectins, gums, some hemicelluloses
viscous fibers
psyllium, b-glucans, pectins, gums
insoluble fibers
lignan, cellulose, some hemicellulose
cellulose found where
major component of plant cell walls. It is abundant in bran, beans, nuts, root vegetables and apples.
cellulose polymer of
glucose with b-1,4 bonds
lignans found where
They are found in the stems and seeds of fruits.
lignans made of
branched polymers of phenolic subunits
hemicellulose found where
in bran, whole grains, and nuts.
hemicelluloses made of
backbone: xylose, mannose, galactose
side chains: arabinose, glucuronic acid, galactose
acidic –> soluble
pectins found where
apples, strawberries
pectins made of
backbone: galacturonic acid
side chains: rhamnose, arabinose, xylose, fucose, and galactose
gums made where
plants secrete to seal wounds
gums made of
backbone w/ branches terminated in galacturonic acid
beta-glucans found where
oats, barley, mushrooms
beta-glucans made of
b-glucans are homopolymers of glucopyranose subunits.
fructans found wehre
asparagus, leeks, onions, garlic, tomato and banana
fructans made of
Fructan structure is fructose + glucose in 1,2 glycosidic bond, with a polyfructose chain bonded to the fructose in 1,6 bond.
which fiber really good for bacteria
gums, pectans, betaglucans
fructans = prebiotic
inulin is a
synthetic fructan
psyllium =
metamucil
soluble fibers do what
Soluble fiber delays gastric emptying, increases transit time through the GI, and decreases nutrient uptake.
viscous fibers do what
Viscous fibers delay gastric emptying, decrease mixing of food with digestive enzymes, decrease nutrient diffusion, and increases small intestine transit time.
insoluble fibers do what
Insoluble fiber decreases intestinal transit time and increases fecal bulk.
SCFAs affect immune cells by
acting as a ligand for GPR43, and by inhibiting histone deacetylases (HDAC).
