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Methyl Jasmonate
C13H20O3
Methyl jasmonate
(MeJA) is a substance used in plant defense and is currently
being used in cancer research. Plants produce jasmonic
acid and methyl jasmonate in response to many biotic and abiotic
stresses (particularly herbivory and wounding), which build up
in the damaged parts of the plant. Jasmonates act as signalling
compounds for the production of phytoalexins. MeJa has been used
to stimulate traumatic resin duct production in lodgepole pine
trees. This can be used as a defense against many insect
attackers as a type of vaccine. Phytoalexins, once ingested by
the attacker
(e.g., insect), can be toxic or interfere with
its
digestion and may deter the attacker from further feeding. The
jasmonate signal often spreads systemically throughout the plant
and is a major component of systemic acquired resistance.
MeJA is also a plant hormone involved in tendril (root) coiling
and seed maturation.

Our Methyl Jasmonate is the best available; manufactured
in Japan.
Sounds
like Jasmine
Indeed,
and it smells like it too! It is one of the main
odour components of jasmine (right), along with a
related molecule called Jasmone. Methyl jasmonate
(MeJA) makes up some 2-3% of jasmin oil. 10,000
blossoms are needed to give 1 gram of the oil (10-4 g
per blossom). Methyl jasmonate is also a flavour
ingredient of semi-black (oolong) and black tea. It
is an expensive odour; commercial applications in
detergents containing oxidising bleaches use the
less reactive reduced dihydro- compounds. But
there's much more to methyl jasmonate than a pretty
smell.
What do
you mean?
Methyl
jasmonate occurs widely in plants. Its biosynthesis
starts with linolenic acid and proceeds through a
number of stages involving lipoxidation, cyclisation
and b-oxidation.
What
does methyl
jasmonate do?
Plants
that come under attack by insects or damaged
mechanically produce higher levels of jasmonic acid
and methyl jasmonate, which build up in the damaged
parts of the plant. A model has been proposed in
which wounding and systemin activate a lipase enzyme
in receptor cell membranes resulting in the release
of linolenic acid (the precursor of jasmonic acid)
and activation of proteinase inhibitor genes. If
ingested by the insect, the proteinase inhibitors
can interfere with its digestive system and deter
the insect from feeding. An 18-amino acid peptide
called systemin (Ala-Val-Gln-Ser-Lys-Pro-Pro-Ser-Lys-Arg-Asp-Pro-Pro-Lys-Met-Gln-Thr-Asp)
is the polypeptide wound signalling molecule.
Jasmine
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Jasmine or Jessamine
(Jasminum) (from Arabic and Persian Yasmine, i.e. "gift from
God", via Arabic) is a genus of shrubs and vines in the olive
family (Oleaceae), with about 200 species, native to tropical and
warm temperate regions of the Old World. The majority of species
grow as climbers on other plants or on structures such as
chicken wire, gates or fences. The leaves can be either
evergreen (green all year round) or deciduous (falling leaves in
autumn).
_in_Talakona_forest_small.jpg)
Cultivation
Jasmine is widely cultivated for its flowers,
enjoyed in the garden, as house plants, and as
cut flowers. The flowers are worn by women in
their hair in southern and southeast Asia. Many
species also yield an absolute, which is used in
the production of perfumes and incense.
Consumption in China
Jasmine tisane is consumed in China, where it is
called Jasmine flower tea (茉莉花茶; pinyin: mò lì
huā chá).
Jasminum
sambac flowers are also used to make tea, which
often has a base of green tea, but sometimes an
Oolong base is used. The delicate Jasmine flower
opens only at night during the full moon and is
plucked in the morning when the tiny petals are
tightly closed. They are then stored in a cool
place until night. Between six and eight in the
evening, as the temperature cools, the petals
begin to open. Flowers and tea are "mated" in
machines that control temperature and humidity.
It takes four hours or so for the tea to absorb
the fragrance and flavour of the
Jasmine
blossoms, and for the highest grades, this
process may be repeated as many as seven times.
Because the tea has absorbed moisture from the
flowers, it must be refired to prevent spoilage.
The spent flowers may or may not be removed from
the final product, as the flowers are completely
dry and contain no aroma. Giant fans are used to
blow away and remove the petals from the denser
tea leaves. If present, they simply add visual
appeal and are no indication of the quality of
the tea.
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