Metabolit sekunder dan primer
Metabolit sekunder dan primer
Berdasarkan
pembentukan:
Metabolit
Primer
— Fundamental Building Block
— Digunakan
langsung tanaman/tumbuhan utk pertumbuhan
— Ex. karbohidrat, protein, lemak, Asam nukleat
Metabolit
Sekunder
— Tidak penting atau esensial untuk
perkembangan/eksistensi makhluk hidup
— Misal terpenoid, alkaloid, flavonoid
Carbohydrates
— Carbohydrates
are the sugars made up of glucose and its isomers
— Carbohydrates
come in many different sizes:
— Monosaccharides
made up of one sugar unit (glucose or fructose)
— Disaccharides
made up of two sugar units (sucrose is a glucose and a fructose)
— Polysaccharides
are polymers made up of more than two sugar units
Polysaccharides
— Structural
polysaccharides are used to support plants
— Storage
polysaccharides are used to store energy for later use by the plant
Structural Polysaccharides
— The
most common structural polysaccharide in plants is cellulose. It makes up 40 to 60% of the cell wall. It is also the most common polymer on earth
— Cellulose
is extremely strong due to its chemical organization. It is made of a long chain of beta-glucose
molecules – 100 to 15,000 glucose molecules
Gluey Polysaccharides
— Pectins
are mainly polymers of galacturonic acid.
— Hemicelluloses
are highly variable and are not related to cellulose.
— Grass
hemicelluloses are high in xylose, with small amounts of arabinose, galactose,
and urionic acids. But pea family
(Fabaceae) hemicelluloses are high in arabinose, galactose and urionic acid,
but low in xylose.
— Some
of the most interesting hemicelluloses are not actually used structurally, but
rather are exuded from stems, leaves, roots, or fruits in a sticky mixture
called a gum
Enzymes
— Enzymes
catalyze biochemical reactions. Most
proteins in living cells are enzymes.
— Pure
enzymes that maintain their activity when removed from plants are commercially
important to us.
Oils
— Oils
occur in all parts of a plant, but are most common in seeds. Some seeds have so much oil that it can be
commercially harvested. The most
commonly used oils are cotton, sesame, safflower, sunflower, olive, coconut,
peanut, corn, castor bean, canola, and soybean oils.
— The
most common seed oil fatty acids are oleic acid (one double bond), linoleic
acid (two double bonds), and linolenic acid (three double bonds). Linoleic and linolenic are essential fatty
acids – we can’t make them ourselves.
Waxes
— Waxes
are complex mixtures of fatty acids linked to long-chain alcohols. Waxes comprise the outermost layer of leaves,
fruits, and herbaceous stems and are called EPICUTICULAR waxes. Waxes embedded in the cuticle of the plant
are cuticular waxes. Cutin is another
wax in the cuticle and it makes up most of the cuticle. Suberin is a similar wax that is found in
cork cells in bark and in plant roots.
Both help prevent water loss by the plant.
— Structures
of waxes vary depending on which plant produced them.
— Waxes
are usually harder and more water repellant than other fats.
Metabolite Sekunder?
Mengapa
dibentuk metabolit sekunder?
— Metabolisme primer akan membentu metabolit primer
— Metabolisme sekunder membentuk metabolit
sekunder
— Metabolit intermediet: reaksi yang
terletak antara met primer dan sekunder
dan menghasilkan energi untuk berlangsungnya suatu reaksi.
— Metabolit sekunder merupakan suatu bentuk
untuk survival/pertahanan diri.
— Tanaman tidak dapat berpindah tempat. Misal
tanaman pada lahan yang tercemar, agar tetap survive maka akan membentuk
metabolit sekunder.
— Uk Misal; pada tanaman tembakau dapat
membentuk asam salisilat sebagai antibodi. Bila tembakau terkena virus maka
produksi asam salisilat akan tinggi dan dalam tembakau dapat melakukan proses
metilasi pada as salisilat menjadi metil salisilat.
— Misal; tanaman membentuk suatu phytoaleksin
Functions of Secondary Compounds
— The
most common roles for secondary compounds in plants are ecological roles that
govern interactions between plants and other organisms.
— Many
secondary compounds are brightly colored pigments like anthocyanin that color
flowers red and blue. These attract
pollinators and fruit and seed dispersers.
— Nicotine
and other toxic compounds may protect the plant from herbivores and microbes.
— Other
secondary compounds like rubber and tetrahydrocannabinil (THC) from cannabis
plants have no known function in plants.
Berdasarkan
sifat:
— Metaboli/zat aktif
— Metabolit/Zat inert
Berdasarkan
reaksi/keaktifan:
— Zat aktif farmasetis
— Zat aktif farmakologik
penghambatan
karsinogenensis, anti-tumor, antivirus,anti-oksidasi (peroksidasi lipida,
lipoksigenase,oksidasi xanthin, dan oksidasi monoamin), antihipertensi ,(antibakteri
dan jamur, anti-diabetes, dan antinematoda
Keragaman
struktur metabolit sekunder
Atas dasar
struktur kimia:
— Senyawa fenolik; asam lmak, flavonoid,
antrakuinon
— Terpenoid
— Alkaloid
Atas dasar
jalur biosintesis: Jalus asam asetat, Jalur asam sikimat, Jalur asam amino
Atas dasar
sifat sensorik: Zat pahit, zat manis, zat pedas, zat berasa kelat (sepat)
Alkaloids
Alkaloids generally include alkaline substances that have nitrogen
as part of a ring structure. More than
6500 alkaloids are known and are the largest class of secondary compounds.
They are very common in certain plant families, especially: peas –
Fabaceae, sunflower – Asteraceae, poppy – Papaveraceae, tomato – Solanaceae, dogbanes – Apocynaceae, milkweeds – Asclepiadaceae, citrus –
Rutaceae.
Terpenoids
— Terpenoids
are dimers and polymers of 5 carbon precursors called isoprene units (C5
H8).
— Terpenoids
often evaporate from plants and contribute to the haze we see on hot sunny
days. They are expensive to make; they
often take 2% of the carbon fixed in photosynthesis; carbon that could otherwise
be used for sugars.
Phenolics
— Compounds
that contain a fully unsaturated six carbon ring linked to an oxygen are called
phenolics.
— Salicylic
acid (basic part of aspirin) is a simple phenol.
— Myristicin
is a more complex phenol that provides the flavor of nutmeg.
— Flavonoids
are complex phenolics. They are often
sold in health food stores as supplements to vitamin C. The most commonly available flavonoid is
rutin from buckwheat.
— Anthocyanins
are a type of flavonoid that give flowers red and blue pigments.
— Some
phenolics form polymers.
— Tannins
are astringent to the taste. They give
dryness (astringency) to dry wines. They
can also be used to tan leather. They
often give water a tea-colored look.
Tannins are common in pines and oaks.
— Lignin
is a major structural component of wood.
The exact structure of lignin is complex and not known.
Minor Secondary Metabolites
— Mustard
oil glycosides are nitrogen-sulfur containing compounds that occur in cabbage,
broccoli, horseradish, watercress and
other members of the mustard family (Brassicaceae). They give the group its characteristic taste
and odor.
— Cyanogenic
glycosides occur in several families of plants, but are especially common in
roses (Rosaceae) and peas (Fabaceae).
They are sugar containing compounds that release cyanide gas when
hydrolyzed.
— Cardiac
glycosides effect vertebrate heart rate.
Especially common in milkweeds Asclepiadaceae.
— The
parsley/carrot family Apiaceae is noted for having aromatic and poisonous 17
carbon polyacetylenes, though a few species have alkaloids like Coniium.
Metabolit
sekunder bagi tanaman sebenarnya juga toksik. Cara antisipasi?
— Akan dibentuk glukosida
— Met sekunder toksik-------glukosida (larut
air)
— Sehingga ketoksikan berkurang dan dapat
ditransport ke vakuola (bila mengekstraksi tanaman akan diperoleh banyak
glikosida)
Biosintesis
Metabolit Sekunder
— Biosintesis metabolit sekunder sangat beragam
tergantung dari goIongan senyawa yang bersangkutan. Jalur yang biasanya dilalui
dalam pembentukan metabolit sekunder ada tiga jalur, yaitu jalur asam asetat,
jalur asam sikimat, dan jalur asam mevalonat.
Keragaman
metabolit sekunder
— Faktor Luar:
Letak geografis
(iklim, suhu, jenis tanah, lingkungan), m.o patogen, sinar matahari
— Faktor dalam; genetis
— Proses: saat panen, pasca panen
Good luck uas..
!!!
Me ^_^
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