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.
Methyl
Jasmonate 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 jasmine 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._in_Talakona_forest_small_2.jpg)
_in_Talakona_forest_small.jpg)
Cultivation of Jasmine
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 of Jasmine 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.
References:
-
B.A.Vick and D.C.Zimmerman, Plant Physiol, 1984, 75, 458 (biosynthesis of MeJA)
-
G.H.Posner and E.Asirvatham, J.Org.Chem., 1985, 50, 2589 (synthesis of MeJA)
-
Synform, 1990, 8, 260 (MeJA synthesis rev.)
-
T.E.Acree et al, J.Agric.Food.Chem. 1985, 33, 425 (odour of isomers of MeJA)
-
http://www.xs4all.nl/~bacis/bnb99041.html (odour of jasmine)
-
D. M. Wang, K. Kubota and A. Kobayashi, Biosci. Biotech. Biochem., 1996, 60, 508 (MeJA in tea).
-
E.E.Farmer and C.A.Ryan, Proc.Nat.Acad.Sci. US, 1990, 87, 7713 (MeJA in interplant communication)
-
D.R.Bergey et al., Proc.Nat.Acad.Sci., US, 1996, 93, 12053 (MeJA and signalling)
-
L.Holbrook et al., Plant Physiol., 1997, 114, 419 (isomers of MeJA and activity)
-
F.Schroder, Angew.Chem.Int.Ed.Engl., 1998, 37, 1213 (review of chemical defence in plants)
-
M.W.Sabelis et al., Science, 2001, 291, 2104 (MeJA and predator attraction)
-
P.Mucha, et al., Coll.Czech.Chem.Comm., 1999, 64, 553 (synthesis and structure of systemin)
-
Y.Yukimune et al., Nature Biotechnol, 1996, 14, 1129 (MeJA in paclitaxel synthesis)
-
R.E.B.Ketchum et al., Biotechnology and Bioengineering, 1998, 62, 97 (MeJA in paclitaxel synthesis)
-
S.Meir et al., Can.J.Bot., 1996, 74, 870 (MeJA as a produce protector)
-
Flescher E (2005). "Jasmonates--a new family of anti-cancer agents". Anticancer Drugs 16 (9): 911–6. doi:10.1097/01.cad.0000176501.63680.80. PMID 16162967.
