Exp 5 Flashcards
“sugar ethers”; a compound that yield 1 or more sugar and a non-sugar component among the products of hydrolysis
Glycosides
functions of glycosides
- regulatory, productive, & sanitary compounds
- cardiac glycosides, laxatives, local irritants, analgesics, etc
two components of glycosides
• glycone
• aglycone (genins)
what are the components of glycone?
• sugar component
• common denominator
• inactive
what are the components of aglycone?
• non-sugar component
• basis of classification
• active
if it’s glucose, it’s called?
glucoside
if it’s fructose, it’s called?
fructoside
if it’s galactose, it’s called?
galactoside
if it’s glucoronic acid, it’s called?
glucoronide
four classifications based on glycosidic bond
C, O, N, S
classification based on aglycone portion
alcohol, aldehyde, anthraquinone, chromone, coumarin, cyanogenic, flavonoid, iridoid, isothiocyanate, phenol, saponin, steroidal, & steviol
the aglycone portion is an alcohol derivative
alcohol glycosides
source of alcohol glycosides
willow bark (salix purpurea, s. fragilis)
the aglycone portion is an aldehyde derivative
aldehyde glycosides
source of aldehyde glycosides
vanilla (vanilla planifolia, v. tahitensis)
• largest group of naturally occuring quinone pigments
• dyes, cathartics, stimulant laxative (habit-forming
anthraquine glycosides
• derivatives are often orange-red compounds that are soluble in hot water and in dilute alcohol
• gives a characteristic red, violet, green, or purple color with a base
anthraquinone glycosides
tests for anthraquinone
bontrager’s test & modified bontrager’s test
result of bontrager’s test
red coloration in the lower ammoniacal layer
result of modified bontrager’s test
pink color
sources of anthraquinone
• cascara sagrada
• frangula
• aloe vera
• rhubarb
• indian rhubarb
• senna
• chrysarobin
the aglycone portion are derivative of benzo-δ-pyrone nucleus
chromone glycosides
sources of chromone glycosides
• hypericum erectum
• japanese eurya (eurya japonica)
• cassia multijuga
the aglycone portion are derivative of benzo-α-pyrone nucleus
coumarin glycosides
sources of coumarin glycosides
• tonka bean (dipteryx odorata)
• meadowsweet (filipendula ulmaria)
• sweet clover (melilotus officinalis)
• vanilla grass (anthoxanthum odoratum)
• yields hydrocyanic acid upon hydrolysis
• often found in legumes, root crops, and grasses
• usually in plants together with hydrolytic enzymes
cyanogenic glycosides
most cyanogenic glycosides are lost after plant harvest due to what?
spontaneous hydrolysis
laetrile, thought to have anti-tumor properties
amygdalin
test for cyanogenic glycosides
guignard’s test
appearance of various shades of red within 15 mins when the tube is warmed (yellow to brick red)
guignard’s test
sources of cyanogenic glycosides
wild cherry (prunus serotina)
apricot (prunus armeniaca)
almond (prunus amygdalus)
cassava (manihot esculenta)
• phenolic plant pigments containing a benzo-y-pyrone nucleus
• anthocyanins, leucoanthocyanins, catechins, aurones, calchones
• anti-viral, anti-fungal, anti-inflammatory, and cytotoxic
flavonoid glycosides
anthocyanins on hydrolysis yield sugars and colored aglycones
anthocyanidins
the aglycone of leucoanthocyanins
leucoanthocyanidin
test for flavonoid
bate-smith & metcalf test, wilstatter “cyanidin” test
result of bate-smith & metcalf test
strong red or violet color
result wilstatter “cyanidin” test
colors range from orange to red, to crimson and magenta, and occassionaly to green or blue
examples of flavonoid glycosides
• hesperidin
• naringin
• rutin
• quercitin
the aglycone portion is an iridoid, usually bound to the glycone portion glucose
iridoid glycosides
sources of iridoid glycosides
• asterids (aucuba japonica, eucommia ulmoides) - aucubin
• catalpa (catalpa bignonioides, c. speciosa) - catalpol
• derived from the hydrolysis of glucosinolates
• anti-cancer
isothiocyanate glycosides
sulphur-containing compounds found in cruciferous plants
glucosinolates
sources of isothiocyanate glycosides
• black mustard (brassica nigra)
• white mustard (brassica alba)
the aglycone portion is a phenol group
phenol glycosides
source of phenol glycosides
bearberry (arctostaphylos uva-ursi)
• cardiac glycoside
• prominent effect on the heart muscle
steroidal glycosides
cyclopentanoperhydrophenanthrene nucleus
steroidal nucleus
cyclopentanoperhydrophenanthrene
steroidal skeleton
more common, has optimum activity, C-23, 5-membered lactone ring
cardenolide
less common, less activity, C-24, 6-membered lactone ring
bufadienolide
test for steroidal
• keller-killiani test
• liebermann-burchard test
• kedde’s test
test for 2-deoxysugars; reddish-brown which may turn blue or purple
keller-killiani test
test for unsaturated steroids and triterpenes; colors range from blue to green, red, pink, purple, or violet
liebermann-burchard test
test for unsaturated lactones; blue-violet color
kedde’s test
sources of steroidal
foxglove, grecian foxglove, convallaria, pheasant’s eye, black hellebore, dogbane, adelfa, strophantus, ouabain, squill, red squill
• the aglycone portion is a steviol
• natural sweeteners, as sub for sugar (40-300 times sweeter than sucrose)
steviol glycosides
source of steviol
stevia (stevia rebaudiana)
harmless when taken orally
saponins
two types of saponins
• steroidal (monocot families; dioscoreaceae)
• triterpenoidal (dicot; agavaceae)
steroidal/triterpenoid glycosides characterized by their ability to froth when agitated
saponin used as detergent
exert a powerful hemolytic action on RBCs and are highly toxic when injected into the bloodstream
saponin used as fish poison
contains sapotoxin which is a poisonous saponin
saponin with interesting spermicidal & molluscicidal activity
used to produce acid saponin if present are precipitated as lead salts
neutral lead acetate
used to precipitate neutral saponin
basic lead acetate
used to decompose lead precipitate
hydrogen sulfide
properties of saponin glycoside
• amorphous; soluble (H2O & alc)
• persistent froth
• hemolysis of RBC’s
• bitter, acrid taste
test for saponins
• froth test
• agar cup hemolytic test
• fehling’s test
• baryta water test
• lead acetate test
extract used for saponins physical test
gugo extract
color, odor, and taste of gugo extract
• golden yellow to orange
• odorless
• slightly bitter, acrid
sources of saponins
• licorice (glycyrrhiza glabra)
• yam (dioscorea floribuna, d. alata)
• ginseng (panax ginseng, p. quinquefolius)
• gugo (entada phaseoloides)
philippine sources
adelfa, akapulko, campanero, campanilla, gugo, kalumbibit, lukban, maguey, pistula, sabila
official usp 24/nf 19 drugs
7 usp 24
4 nf 19
