connection between monosaccharides

alpha-digestable

beta-not

mono-simple sugars

di-2

oligo-3-10

poly->10

most important

mono-glucose,fructose,galactose

di-maltose,sucrose,lactose

simplest carbohydrates

aldehydes and ketones (2+ hydroxyl groups)

used by animals to derive enery via glycolysis and the TCA cycle

building blocks for nucleic acids (ribose)

major energy containing part of plants

sugars, starch, and fiber

can be synthesized from amino acids (proteins) via gluconeogenesis

 C6H12O6 ALDEHEXOSE

major end-product of carbohydrate digestion in monogastric animals

dextrose in (corn syrup, molasses, icing sugar)

part of lactose

C6H12O6 ALDOHEXOSE

less sweet and less water soluble than glucose

major component of oligosaccharides in soybeans

cannot be converted to glucose by avians

sweetest of the sugars

C6H12O6 KETOHEXOSE

part of sucrose

naturally occuring in ripe fruit, honey and molasses

high fructose corn syrup

sweetness increases with age (fruit sweetens as it ripens)

mannose: aldohexose, exhibits non-nutritive benefits

Ribose: aldopentose (5 carbon), part of nucleic acid

xylose and arabinose-alsopentoses, combine to form arabinoxylan

dissaccharide

glucose+glucose+alpha(1-4) linkage

starch digestion end-product

found in malt (found in brewing beer)

brush border membrane enzyme maltase

dissaccharide

glucose+glucose

alpha (1-6) linkage

branching point of amylopectin

brush border membrane enzyme isomaltase

dissaccharides

Glucose and fructose

C1 linked to C2

table sugar

from sugar cane, sugar beets, maple syrup

brush border membrane enzyme sucrase

mix of glucose and fructose

 monosaccharide composition almost the same as sucrose

two types: 42% or 55% fructose

same sweetness and caloric content as sucrose

glucose and galactose

beta(1-4) linkage

simplest beta galactoside

milk sugar

brush border membrane enzyme: lactase

used in pills as a filler material

important energy source for suckling animals

lactase activity usually decreases with age

lactose--lactic acid

suckling animal may experience decrease in pH to 2-4

kills pathogenic bacteria

improved protein digestion since ability to secrete gastric HCl is not fully developed

Glucose+glucose

beta (1-4) linkage cannot be cleaved by mammalian enzymes

enzyme for hydrolysis: cellulase, from bacteria or fungi

Oligosaccharides

raffinose,stachyose,verbascose

galactose and sucrose (glucose and fructose)

soybean meal: 1.6% raffinose

5.6% stachyose

also legumes seeds

leads to flatulence and odor

problem with pet foods

oligosaccharides

mainly fructose units and some other mono..

found in artichoke, onion, harlic, bananas, chicory root

not digested by mammalian enzymes

non-nutritive sweetener for diabetics

promotes growth of lactic acid producing bacteria (bifidobacteria) and suppresses pathogeni bacteria (E. coli)

Polysaccharide-digestable

most prominent carbohydrate source in commercial animal foods/feeds

seeds 70% tubers/roots 30%

...

present as starch granules:tightly arranged residual t rupture (H bonding) cooking causes gelatinization or irreversible change to structure

...

two types of polysaccharides present in starch Amylose (helis d-glucolse and 1-4 linkages) and Amylopectin (straight chain (1-4) and alpha (1-6)brances every 25 units)

Polysaccharide

occurs in liver and muscle-storage in animals

straight chain D-glucose with alpha (1-4) and alpha (1-6) linkages but more branching than in amylopectin

Starch chopped by amylase turns to dextrins chopped by amylase to become maltose chopped by maltase to become D-Glucose

....

salivary amylase-minor role in digestion (not present in ruminants or carnivores)

pancreatic-most important enzyme in starch digestion, secretion active (requires chloride) and sensitive to changes in starch in take (resistant to breakdown), also secreted from bovine pancreas...contains bicarbonate ph 8.1-8.6 to up ph and optimize digestion ph 5-7

70-80% starch

corn, rice

wheat, oats

pet food

barley,carrots, flax seed, molasses, peas, potatoes

grinding removes physical entrapment of starch

(exposure of starch granules to amylase)

...

starch is the primary ingredient needed for extrusion of food/feeds

gives it structure and cohesion

...

Cooking greatly enhances digestibility

maillard-type browning-non-enzymatic, binds nitrogen-containing nutrients (makes mono... unavailable to aa), fructose more readily affected than glucose (toast, alfalfa haylage and soybean meal)

plant material that consists of several forms of carbohydrates

cellulose, hemicellulose, pectin (all non starch polysaccharides)

lignin-holds everything together but isnt a carbohydrate

provide rigidity in plants (structural) stems, leaves, seed, etc in cell wall.

fermented by microbes, but undigestable by mammalian enzymes

dietary fiber beta (1-4) linkage

fermetative breakdown slow due to H-bonding and tight packing of glucan chains

Most common organic compound on earth

linear chains of several hundred to over ten thousand D-glucose units

dietary fiber

beta (1-4) linkages of mono.. including glucose, xylose, arabinose and galactose

fermentability is greater than cellulose

shorter chain lenght (200 mono...) but more complex structure

about 20% of plant matter

arabinoxylan:composed of pentosans (xylose and arabinose)cereal grains: wheat, corn, barley and rye

increases viscocity of intestinal contents

more fermentable in cellulose

.....

Pectin:citrus fruits, apples, citrus by-products

easily and readily fermented by bacteria in colon

increases viscosity of intestinal contents more than arabinoxylan

provides rigidity to cell wass, interferes with breakdown of cellulose and is quite resistant to degradation

wood products, mature hay and straw

repeats of phenylpropanoid units

fiber degrading enzymes such as

cellulase, hemicellulase, arabinoxylanase (xylanase or pentosanase) and pectinase

breakdown of fiber or other nutrients by bacteria and release of volatile fatty acids and gasses (CO2, and CH4)

fiber ---> bacterail enzymes ---->monosaccharides----> bacteria ----->VFA+CO2+CH4

Starch (higher git digestion)

Starch-->Glucose--->ATP

Fiber (lower git fermentation)

Fiber-->bacteria-->mono...-->bacteria-->

VFA+CO2+CH4+heat--> ATP

bacteria in colon degrade fiber to various degrees

SCFA or VFA produced

acetate, propionate and butyrate

around 70%

over 90% of the fiber digestion is due to the rumen

• diluent decreasing total energy densit of diet
• assists in stimulating normal peristalsis
• provides bulk to intestinal contents to prevent constipation
• reduces gastrointestinal transit time (normal stool freqency)

moderately fermentable sources of fiber are best for pet food

indigestible fiber in pet food:beet pulp, apple/tomato pomace(solid residue after juice are extracted), peanut hulls, citrus pulp, bran of oats rice wheat (milling by-product, outer course coat of cereal grain), cellulose

guaraneed maximum crude fiber content of commercial pet food labels ranges from 3-6% of dry matter in the diet

source of carbohydrate and processing are important

source and level of dietary fiber

highly digestable:

low stool volume and well formed,firm

defecation frequency should be low

bowel movements regular and consistant

normal grown rate and body weight maintained

no need to feed excessive quantities

long term feeding=healthy skin and hair coat

classical analyzing diets and ingredients, earliest classification of chemical components in diets and ingredients

doesnt measure nutrients directly

sequenced designed to move from one analysis to another without destroying sample

economical and simple equipment

NIRS (near infrared spectroscopy)

(CP,CFat,CF, ash,NFE =100% dry matter)

level of nitrogen measured

Kjeldahl procedure (classic):hot acid digestion/sulfuric acid, distillation and titration

combustion method more common: oven temp above 950 C, pure oxygen

Proteins on average contain 16% N

100%/16%=6.25

N*6.25=CP content

uses chromatography methods to measure all aa simultaneously

about 200mg sample hydrolyzed under N2 gas in 6N HCl for 22 hours at 110  degrees C

some AA will be altered/destroyed

• sample placed in filter paper annd ether is reflued through sample
• fat (lipid) components removed by ether
• ether is evaporated, lipid components left behind

sample boiled in acidic solution followed by alkaline solution

ash content in residue is determined and ash subtracted from residue to calculate crude fiber

...

crude fiber contains parts of cellulose, hemicellulose and lignin

>>>
Van Soest Method: extraction and filtration (2 components)

Neutral detergent fiber (NDF)- hemicellulose, cellulose and lignin

Acid detergent fiber (ADF)- cellulose an dlignin

Hemicellulose = NDF-ADF

sample burned at 500 degrees C

all organic (C) compounds are removed as CO2

ash consists of al the mineral in the sample

if individual minerals are to be measured, this can be done from ash

carbohydrates (starch,sugar, oligosaccharides, pectin and hemicellulose)

may be negative especially if reedstuffs do not contain carbohydrates

NFE=100-(Protein+fat+fiber+ash+moisture) as-is basis

represents compounds containing C

OM=DM-ash

bones, bovine hides, pig skin

lots of collagen

structural

enzymes

hormones

carriers in blood

cellular regulator of genes

antibodies (immune defenses)

complex organic compounds of high molecular weight

C skeloton (51-55%)

H (6-7)

O (22-24%)

N (16-18%)

CP=%N * 100/16 = %N*6.25

yield only AA or their derivatives when hydrolyzed in acid (HCl)

Fibrous: collagen, elastin, keratin

Globular: albumins, globulins, glutelins (enzymes, hormones)

phosphoproteins

glycoproteins

liporoteins

chromoproteins

nucleoproteins

amides-urea, uric acid, allantoin

amines-decarboxylated aa, toxic and good

free aa-usually minor

alkaloids-many poisonous

nucleic acids-purines and pyrimidines

ammonium salts