Flavounoids Flashcards
Who isolated “Vitamin P” from oranges
Albert Szent-Györgyi credited with this isolation.
What is the basic structure of flavonoids
γ-benzopyrone
Flavonoids are more common in____ plants
Higher
Largest naturally occurring phenols
Flavonoids
What is responsible for colors of flowers fruits and occasionally leaves?
Flavonoids
What gives petals their color
Anthocyanidins
Cyanidine- Red Delphinidine-Blue
Flavonoids can occur as free state and as glycosides
T or F
True
• The yellow anthochlor pigments of anthocyanadines are produced from?
chalcones and aurones.
Glycosidic flavonoids are soluble in?
Genins are soluble in??
Polar solvents
Aglycone - non polar organic
What makesflavonoids good antioxidants and what increases its antioxidant capacity
ability to chelate Fe2+ and Cu2+ and scavenge free radicals renders them very good antioxidants.
• The greater the number of hydroxyl groups the greater the antioxidant capacity of the flavonoid.
What are the types of flavonoids based on
Degree of oxidation of C ring and hydroxylation of C-3
What are the four o glycosides if flavonoids
Quercetin, Kaempferol, Myricetin, Rutin.
KuMyRuQuer
Kumerica
colourless pigments in the leaves of plants
They are building blocks of anthocyanins
• Beverages such as tea and red wine are also important sources
Flavanols
What polymethoxylated flavones are the peels of citrus fruits rich in
Tagretin Nobiletin sinensetin
TNOS
The nose
What are the three examples of flavones
Luteolin Apigenin Chrysin
LAC
Present in all the citrus fruits and responsible for bitter taste of citrus fruit peels
Flavanones
What are the three flavanones
HEN
Hesperitin
Naringenin
Eriodictyol
HEN
Predominantly found in legumes and soyabeans
Occur in mycobacterium phlei
ISO-flavonoids
What are the three iso-flavonoids
GDP
Genistein
Daidzen(phytoestrogens)
Prunetin
The 5 anthocynanides
Cyanidin Delphinidin Malvidin Pelargonidin Peonidin
Characterized by the absence of the 2nd ring of the basic structure and referred to as open chain flavonoids.
Chalkones
Eg include Phloridzin, Arbutin, Phloretin, Chalconaringenin
Also referred to as “condensed tannins”
Responsible for astringency in many foods and medicinal herbs
Proanthocynanide
are basically flavanols.
There are two chiral centers on the molecule; Carbons 2
and 3. Therefore, it has four diastereoisomers.
Flavan-3-ol
What color do flavonoids give for FeCl3 Alkalis and AlCl3 and what makes them give those colors
Blue colour with FeCl3
Yellow colour with Alkalis
Yellow colour with AlCl3
Flavonoids contain the benzopyran nucleus, and occur either as aglycones or as
glycosides.
• The aglycones are pale yellow and their glycosides are colourless.
