An unusual 4-methyl sterol present in abyssal sediments from the north-east Atlantic Ocean

Authors

  • V.L.C.S. Santos Instituto de Química, UFBA Campus, Universitário de Ondina Salvador, 40170 290 Salvador, Bahia, Brazil
  • D.S.M. Billett Southampton Oceanography Centre, Empress Dock, Southampton SO14 3ZH, UK
  • G.A. Wolff Oceanography Laboratories, Department of Earth Sciences, University of Liverpool, Liverpool L69 3BX, UK

Keywords:

4α-Methyl-5α-(H)-cholestan-3β-ol, Porcupine Abyssal Plain

Abstract

Four undisturbed sediment cores were collected from the Porcupine Abyssal Plain, an area in the north-east Atlantic ocean (48°N,16°W) characterised by seasonal surface phytoplankton blooms which lead to the pulsed input of organic matter to the benthos of which holothurians are considered to be the dominant biomass. In order to investigate the geochemistry of sedimentary organic matter in the deep ocean, these sediments were analysed for sterols by gas chromatography and mass spectrophotometry. Ten sterols were detected in the surficial sediments (Z-cholesta-5,22-dien-3β-ol, E-cholesta-5,22-dien-3β-ol, cholest-5-en-3β-ol, 5α(H)-cholestan-3β-ol, 24-methylcholesta-5,22-dien-3β-ol, 4α-methyl-5α(H)-cholestan-3β-ol, 24-ethylcholesta-5,22-dien-3β-ol, 24-ethylcholest-5-en-3β-ol, 5α(H)-24-ethyl-cholestan-3β-ol, 4α,23,24-trimethyl-5α-cholest-22-en-3β-ol) which decreased rapidly in concentration with increasing sediment depth. The prominent sterol of almost all surficial samples was 4α-methyl-5α-(H)-cholestan-3β-ol, the predominant sterol in two out of four samples. The exact reason for the abundance of this unusual compound in marine sediments is still not clear. However, two possible explanations for its high concentration are: (i) a contribution from one or several species of dinoflagellate (or possibly other algae) that were present in the phytoplankton bloom, which occurred in surface waters some two months prior to sampling; and (ii) a contribution to the sediment by benthic invertebrates (from faecal material), specifically holothurians. The total sterol concentration rapidly decreased with depth in the sediments and in the deeper sections of all of the cores, only cholest-5-en-3β-ol and 24-ethyl-cholest-5-en-3β-ol were detected.

References

Ballantine, J.A., Lavis, A. and Morris, R.J. 1979. Sterols of phytoplankton — effects of illumination and growth stage. Phytochemistry, 18: 1449–1466.

Barnett, P.R., Watson, J. and Cornnelly, D. 1984. A multiple corer for taking virtually undisturbed samples from shelf, bathyal and abyssal sediments. Oceanol. Acta, 7: 401–408.

Barrett, S.M., Volkman, J.K., Dunstan, G.A. and LeRoi, J.M. 1995. Sterols of 14 species of marine diatoms (Bacillariophyta). J. Phycol., 31: 360–369.

Balsam, W.L. and McCoy, F.W. Jr. 1987. Extractable and bound neutral lipids in some lacustrine sediments. Org. Geochem., 6: 223–236.

Billett, D.S.M., Lampitt, R.S., Rice, A.L. and Mantoura, R.F.C. 1983. Seasonal sedimentation of phytoplankton to the deep-sea benthos. Nature, 302: 520–522.

Billett, D.S.M. 1991. Deep-sea holothurians. Oceanogr. Mar. Biol. Annu. Rev., 29: 259–317.

Bouvier, P., Rohmer, M., Benveniste, P. and Ourisson, G. 1976. Δ8(14) steroids in the bacterium Methylococcus capsulatus. Biochem. J., 159: 267–271.

Brault, M. and Simoneit, B.R.T. 1988. Steroid and triterpenoid distribution in Bransfield Strait sediments: hydrothermally enhanced diagnetic transformation. Org. Geochem., 13: 697–705.

Cremer, M., Grousset, F., Faugeres, J.C., Gonthier, D. and Gonthier, E. 1992. Sediment flux pattern in the northeastern Atlantic: variability since the last Interglacial. Mar. Geol., 104: 31–53.

Gagosian, R.B. 1976. A detailed vertical profile of sterols in Sargasso Sea. Limnol. Oceanogr., 21: 702–710.

Gagosian, R.B. and Nigrelli, G.E. 1979. The transport and budget of sterols in the western North Atlantic Ocean. Limnol. Oceanogr., 28: 838–849.

Gagosian, R.B., Smith, S.O., Lee, C., Farrington, J.W. and Frew, M.N. 1980. “Steroid transformations in recent marine sediments”. In Advances in Organic Geochemistry, Edited by: Douglas, A.G. and Maxwell, J.R. 407–419. Oxford, , UK: Pergamon. In

Gaskell, S.J. and Eglinton, G. 1976. Sterols of a contemporary lacustrine sediment. Geochim. Cosmochim. Acta, 40: 1221–1228.

Goad, L.J. 1978. “The steroids of marine invertebrates: composition, biosynthesis and metabolites”. In Marine Natural Products, Chemical and Biological Perspectives, Edited by: Scheuer, P.J. Vol. 2, 213–318. New York: Academic Press. In

Goad, L.J. 1981. Sterol biosynthesis and metabolism in marine invertebrates. Pure Appl. Chem., 51: 837–852.

Goad, L.J. and Withers, N. 1982. Identification of 27-nor-(24R)-24-methylcholesta-5,22-dien-3β-ol and brassicasterol as the major sterols of the marine dinoflagellate Gymnodinium simplex. Lipids, 17: 853–858.

Goad, L.J., Holtz, G.G. Jr. and Beach, D.H. 1983. Identification of 24(S)-24-methylcholesta-5,22-dien-3β-ol as the major sterol of a marine Cryptophyte and a marine Prymnesiophyte. Phytochemistry, 22: 475–476.

Goad, L.J., Garneau, F.X., Simard, J.L., Apsimon, J.W. and Girard, M. 1986. Composition of the free, esterified and sulphated sterols of the sea cucumber Psolus fabricii. Comp. Biochem. Physiol., 84B: 189–196.

Huang, W.-Y. and Meinschein, W.G. 1979. Sterols as ecological indicators. Geochim. Cosmochim. Acta, 43: 739–745.

Jahnke, L.L. 1992. The effects of growth temperature on the methyl sterol and phospholipid fatty acid composition of Methylococcus capsulatus (Bath). FEMS Microbiol. Lett., : 209–212.

Jahnke, L.L., Stan-Lotter, H., Kato, K. and Hochstein, L.I. 1992. Presence of methylsterol and bacteriohopanepolyol in outermembrane preparation from Methylococcus capsulatus (Bath). J. Gen. Microbiol., 138: 1759–1766.

Lajart, M., Saliot, A. and Schimmelmann, A. 1990. Free and bound lipids in recent (1835–1987) sediments from Santa Barbara Basin. Org. Geochem., 16: 793–803.

Lampitt, R.S. 1985. Evidence for the seasonal deposition of detritus to the deep-sea floor and its subsequent resuspension. Deep Sea Res., 32: 885–897.

Lin, D.S., Ilias, A.M., Connor, W.E., Cadwell, R.S., Cony, H.T. and Daves, G.D. Jr. 1982. Composition and biosynthesis of sterols in selected marine phytoplankton. Lipids, 17: 818–824.

Morris, R.J. and Culkin, F. 1977. Marine lipids: sterols. Oceanogr. Mar. Biol. Annu. Rev., 15: 73–102.

Nicholls, P.D., Skerratt, J.H., Davidson, A., Burton, H. and McMeekin, T.A. 1991. Lipids of cultured Phaeocystis pouchetii: signatures for food-web, biogeochemical and environmental studies in Antarctica and the Southern ocean. Phytochemistry, 30: 3209–3214.

Pelzer, E.T. and Gagosian, R.B. 1989. “Organic geochemistry of aerosol over the Pacific ocean”. In Chemical Oceanography, Edited by: Riley, J.P., Chester, R. and Duce, R.A. Vol. 10, 282–338. London: Academic Press. In

Rice, A.L., Billet, D.S.M., Fry, J., John, A.W.G., Lampitt, R.S., Montoura, R.F.C. and Morris, R.J. 1986. Seasonal deposition of phytodetritus to the deep-sea floor. Proc. R. Soc. Edinburgh, 88B: 265–279.

Rice, A.L., Billet, D.S.M., Thurston, M.H. and Lampitt, R.S. 1991. The Institute of Oceanographic Sciences biology programme in the Porcupine Seabight: background and general introduction. J. Mar. Biol. Assoc. UK, 71: 281–310.

Rice, A.L. and Lambshead, P.J.D. Patch dynamics in the deep-sea benthos, the role of a heterogenous supply of organic matter. Aquatic ecology: scale pattern and process. Proceedings of the British Ecological Society/American Society of Limnology and Oceanography Symposium. April 5–8 1992. Cook: University College.

Robinson, N., Cranwell, P.A., Finlay, B.J. and Eglinton, G. 1984. Lipids of aquatic organisms as a potential contributors to lacustrine sediment. Org. Geochem., : 143–152.

Santos, V.L.C.S. 1993. Biogeochemistry of deep-ocean sediments from Porcupine Abyssal Plain in the north-eastern Atlantic, UK: University of Liverpool. PhD thesis

Santos, V.L.C.S., Billett, D.S.M., Rice, A.L. and Wolff, G.A. 1994. The fate of organic matter in deep sea sediments from the Porcupine Abyssal Plain. I. Lipids. Deep Sea Res., 41: 787–819.

Smallwood, B.J., Bett, B.J., Smith, C.R., Gage, J.D., Patience, A., Hoover, D. and Wolff, G.A. 1999. Megafauna can control the quality of organic matter in marine sediments. Naturwissenschaften, 86: 320–324.

Smith, D.J., Eglinton, G., Morris, R.J. and Pontanem, E.L. 1982. Aspects of the steroid geochemistry of a recent diatomaceous sediment from Namibian shelf. Oceanol. Acta, 5: 365–378.

Svetashev, V.I., Levin, V.S., Lam, C.N. and Nga, D.T. 1991. Lipid and fatty acid composition of holothurians from tropical and temperate waters. Comp. Biochem. Physiol., 98B: 489–494.

Thiel, H., Pfannkuche, O., Schiiever, G., Lochte, K., Gooday, A.J., Hemlebera, C., Mantoura, R.F.C., Turley, C., Patching, J.W. and Riemann, F. 1990. Phytodetritus on the deep-sea floor in a central oceanic region of the north Atlantic. Biol. Oceanogr., 6: 203–239.

Venkatesan, M.I., Ruth, E., Steinberg, S. and Kaplan, I.R. 1987. Organic geochemistry of sediment from the continental margin off southern New England, USA. Part II. Lipids. Mar. Chem., 21: 267–299.

Volkman, J.K., Smith, D.J., Eglinton, G., Forsberg, T.E.V. and Corner, E.D.S. 1981. Sterol and fatty acid composition of four marine Haptophycean algae. J. Mar. Biol. Assoc. UK, 61: 509–527.

Volkman, J.K. 1986. A review of sterol markers for marine and terrigenous organic matter. Org. Geochem., 9: 83–99.

Volkman, J.K. and Hallegraeff, G.M. 1988. Lipids in marine diatoms of the genus Thalassiosira predominance of 24-methylenecholesterol. Phytochemistry, 27: 1389–1394.

Volkman, J.K., Farrington, J.W. and Gagosian, R.B. 1987. Marine and terrigenous lipids in coastal sediments from the Peru upwelling regions at 15°S: sterols and triterpene alcohols. Org. Geochem., 11: 463–477.

Volkman, J.K., Kearney, P. and Jeffrey, S.W. 1990. A new source of 4-methyl sterols and 5α(H)-stanols in sediments: prymnesiophyte microalgae of the genus Pavlova. Org. Geochem., 15: 489–497.

Volkman, J.K., Barrett, S.M., Blackburn, S.I., Mansour, M.P., Sikes, E.L. and Gelin, F. 1998. Microalgal biomarkers: a review of recent research developments. Org. Geochem., 29: 1163–1179.

Wakeham, S.G. 1987. Steroid geochemistry in oxygen minimum zone of the eastern North Pacific Ocean. Geochim. Cosmochim. Acta, 51: 3051–3069.

Wakeham, S.G. 1995. Lipid biomarkers for heterotrophic alteration of suspended particulate matter in oxygenated and anoxic water columns of the ocean. Deep Sea Res. (I), 42: 1749–1771.

Wakeham, S.G. and Beir, J.A. 1991. Fatty acid and sterol biomarkers as indicator of particulate matter source and alteration processes in the Black Sea. Deep Sea Res., 38: 943–968.

Wakeham, S.G., Hedges, J.I., Lee, C., Peterson, M.J. and Hernes, P.J. 1998. Compositions and transport of lipid biomarkers through the water column and surficial sediments of the equatorial Pacific Ocean. Deep Sea Res. (II), 44: 2131–2162.

Weeks, A.R., Fasham, M.J.R., Aiken, J., Read, D.S. and Bellan, I. 1993. The spatial and temporal development of the spring bloom during the JGOFS North Atlantic Bloom Experiment, 1989. J. Mar. Biol. Assoc. UK, 73: 253–282.

Weeks, A.R., Conte, M.H., Harris, R.P., Bedo, A., Bellan, I., Burkhill, P.H., Edwards, E.S., Harbour, D.S., Kennedy, H., Llewellyn, C., Mantoura, R.F.C., Morales, C.E., Pomroy, A.J. and Turley, C.M. 1993. The physical and chemical environment changes in community structure associated with bloom evolution. The Joint Global Flux Study North Atlantic Bloom Experiment. Deep Sea Res. (II), 40: 347–368.

Published

2000-01-01

Issue

Section

Research article