Abstract:
The fruits of Luffa echinata /800 gm) were extracted with
chloroform 13X48 hours) at room temperature. The chloroform
extracts yielded a deep green solid mass (40 gm) on removal of
the solvent. The chloroform extract was fractionated with nhexane.
The n-hexane insoluble part gave a green solid Mass L /30
gm). On decolourization with activated charcoal Mass L yielded a
yellowish solid mass (2S gm) which was noted as Mass L1•
Mass L1 showed the presence of at least six compounds on TLC
plates. Column chromatographic separation of Mass LIon silica
gel with CC14 : EtOAc 11:1) as eluant gave one pure compound A1,a
mixture of two compunds (A2 &: A3) and a fraction which on
concentration gave a crystalline solid. /compound A4). Compound
A2 and compound A3 were separated from the mixture by preparative
TLC. The mother liquor on removal of compound A4 gave a solid
mass, (Mass L2). Mass L2 on further chromatography gave two more
pure compounds, compound AS and compound A6,
Compound AI' A2,A3, A4 and
extensive use of UV, IR, IH NMR,
AS were characterized by
13C NMR and mass spectral
analyses. The compounds are datiscacin(37)/a cucurbitacin-20-
acetate ester darivative) ,(AI' yield 0;013%), cucurbitacin B(41),
(A2, yield 0.266%), isocucurbitacin B(421, (A3, yield 0,109%),3-
sitosterol glucoside(43l, (A4, yield 0.047%) and 2-0-3-Dglucopyranosyl
cucurbitacin B(44), (AS' yield 0.936%). UV and IR
spectra of compound A6 suggested it to be cucurbitacin S
glucoside(4S), (A6, yield 0.043%) but remains to be confirmed.
123
The present investigation has led to the isolation of three
more compounds namely datiscacin(37), 2-0-B-D-glucopyranosyl
cucurbitacin B(44) and cucurbitacin S glucoside(45) besides
cucurbitacin B(41),isocucurbitacin B(42)and a-sitosterol
glucoside(43) from Luffa echinata. Of course the structure of
cucurbitacin S glucoside requires to be more regorously
established.
The ethanol extract of the plant Luffa echinata shows potent
-.~
activity against spasmogen induced contraction in gtil~~~~pig
ileum, poor activity on guinea-pig atria and poor activity
against oxytocin induced contraction in rat uterus.
