Jumat, 19 Oktober 2012

FLAVONOIDS

     Flavonoids have a basic skeleton of 15 carbon terdiriu atomkarbon, in which two benzene rings (C6) bound to a chain of propane (C3) to form an arrangement of C6-C3-C6. This arrangement can produce three kinds of structure of flavonoid compounds. This arrangement can produce three jenisstruktur, the 1.3-diarilpropan or flavonoids, 1.2-diarilpropan or isoflavones, dan1,1-diarilpropan or neoflavon.

      Of the various types of flavonoids, flavones, flavonols, and anthocyanidins are the kind that are found in nature, so it is often stated as the main flavonoids. While the types of flavonoids in nature in limited quantities is calkon, Auron, katecin, flavanones, and leukoantosianidin.

     The number of flavonoid compounds in nature and not due to the many variations in structure, but are caused by different levels of hydroxylation, alkoksilasi, or glycosylation of the structure.

1. Biosynthesis of Flavonoids


     All variants of the flavonoid biosynthesis correlated because the groove itselfyaiut linesSikimat and acetate-malonate pathwayThe model of the biosynthesis of flavonoids has beensuggested by BirchAccording Birchthe steps of the biosynthesis of flavonoids pertamadari aC6-Cberkombinasi units with three units Cmenghasilakan -C3-C6 units (C2 + C2 + C2). C15framework that has been dihasilakan darikombinasi oxygen containing functional groups onyangdiperlukan positionA ring of the flavonoid structure derived from the polyketide route,yaitukondensasi of three units of acetate or malonate. While the B ring and three atomkarbon of the propane chain is Adari phenylpropanoid path (via shikimic.) Thereforethe basic structure of the carbon product darikombinasi biosynthesis of flavonoids between two major avenues for the aromatic ringcalled shikimic and acetate-malonate path . As a result of various perubahanyangcaused by enzymesthe third carbon atom of the propane chain can produce a variety offunctional groupssuch as double bondshydroxylcarbonyl groupsand so on.


Structure of flavonoids undergo secondary reactionssepertihidroksilasioxidation(including training carbonyl), glycosylationmethylationisoprenilasicyclizationand the other for the treatment of enzimyang present in the organismThe product of the enzymatic reactiondapatmenghasilkan flavonoid compounds with different types kerangkadasar different as shownon the classification of flavonoids klasifikasiatau above (Tukiran, 2010)
Figure 9. Principal reaction Flavonoid Biosynthesis

According biosynthesisthe formation of flavonoid started denganmemperpanjang unitsfenilpropanaid (C3-C6) derived from p-amino derivatives sinamatseperti kumarattimes kafeatacidferulic acidor asamsinapatThe experiments have also shown that calkon and flavanonesisomer are comparable also serves as an intermediate in the biosynthesis of various types of otherflavonoids.

1 komentar:

  1. My question :

    whether some types of secondary reactions such as hydroxylation, oxidation, glycosylation, methylation and cyclization experienced by the structure of flavonoids due to enzyme treatment to determine the type basic framework that will be generated on the product flavonoids?
    if so, how the process of the formation of the basic framework of diversity due reaks flavonoid-reaction of the secondary?

    BalasHapus