*Corresponding author. Tel.:#90-312-2122267; fax:#90-312-2133921.
E-mail address:ilkayer@marketweb.net.tr (I0. Erdogyan)
Biochemical Systematics and Ecology 28 (2000) 793}794
Tryptophol, a plant auxin isolated from the
marine sponge
Ircinia spinulosa
I
0
lkay Erdog
y
an
!
,
*
, Bilge S
7
ener
!
, Tatsuo Higa
"
!Department of Pharmacognosy, Faculty of Pharmacy, Gazi University, 06330 Ankara, Turkey
"Department of Biology, Chemistry and Marine Sciences, Faculty of Science, University of the Ryukyus, Nishihara, 903-0213, Okinawa, Japan
Received 23 March 1999; accepted 16 September 1999
Keywords:Tryptophol;Irsinia spinulosa; Sponge; Marine organism
1. Subject and source
A sample of the marine sponge,Ircinia spinulosa, light brown in color, was collected
from the Aegean Sea in Bodrum, Turkey, at a depth of 3 m, in August 1996. A voucher specimen is deposited in the Department of Biology, Faculty of Education, Gazi University.
2. Previous work
Tryptophol [2-(3-indolyl)-ethanol], a well-known constituent of terrestrial plants and microorganisms, has so far been isolated from tryptophan fermentations, plant
seedlings, Aspergillus niger, Agrobacterium tumefaciens, Ceratocystis spp., and
Rhi-zobiumspp. (Buckingham, 1994). We have now isolated tryptophol from the marine
sponge Ircinia spinulosa collected from the Aegean Sea. In addition to terrestrial
sources, tryptophol has been isolated as a plant auxin from the culture media of the
fungiBalansia epichloe(Clavicipitae) (Porter et al., 1985) andDreschslera nodulosum
(Sugawara and Strobel, 1987).
3. Present study
A fresh sample ofIrcinia spinulosa(300 g) was cut into small pieces and extracted
with ethanol at room temperature. The ethanolic extract was concentrated under vacuum and partitioned between ethyl acetate and water. The ethylacetate extract was
concentrated to dryness and fractionated by vacuum#ash chromatography (VFC)
over silica gel. One of the VFC fractions was subjected to centrifugal countercurrent
chromatography (CCC). The"rst CCC fraction gave three subfractions, the second of
which yielded pure tryptophol (6.5 mg) by normal phase HPLC (EtOAc :
Hep-tane/5 : 3). It was identi"ed as tryptophol by comparison with the published
spectro-scopic data given in our previous work (Erdogyan, 1998).
4. Chemotaxonomic signi5cance
Biosynthesis of tryptophol may be either through tryptophan or through
decar-boxylation and deamination reactions (Fenn et al., 1977). ForBalancia epichloe, it was
suggested that this fungus may catabolize endogenous tryptophan to regulate plant growth and 3-substituted indoles like tryptophol may be involved in the regulation of plant growth by this fungus. Tryptophol was also reported to have antibacterial
activity against gram-positive bacteria and Candida albicans (Buckingham, 1994).
Although it is a well-known compound in terrestrial plants and often reported as a by-product of indoleacetic acid metabolism in plants and microorganisms, tryp-tophol has never been reported from a marine organism before. It may be considered to be playing a similar role in regulating growth of marine organisms as in plants.
Acknowledgements
I. Erdogyan thanks the Ministry of Education of Japan (Monbusho) for a
scholar-ship.
References
Buckingham, J., 1994. Dictionary of Natural Products, Chapman & Hall Data Base. Cambridge University Press, Cambridge.
Porter, J.K., Bacon, C.W., Cutler, H.G., Arrendale, R.F., Robbins, J.D., 1985. Phytochemistry 24 (7), 1429. Sugawara, F., Strobel, G.A., 1987. Phytochemistry 26 (5), 1349.
Fenn, P., Durbin, R.D., Kuntz, J.E., 1977. Phytochemistry 16 (5), 899.
Erdogyan, I., 1998. Studies on the Chemical Constituents of Sponges from the Aegean Sea and of the Okinawan SpongeTheonella cupola. M.Sc. Thesis, Graduate School of the University of the Ryukyus, Okinawa.