Applied Biochemistry and Biotechnology

, Volume 55, Issue 2, pp 133–149 | Cite as

NH4OH-Based pretreatment for improving the nutritional quality of single-cell protein (SCP)

  • J. C. Parajó
  • V. Santos
  • H. Domínguez
  • M. Vázquez
Original Articles


The potentiality of treatments with NH4OH solutions for improving the quality of protein concentrates fromCandida utilis biomass was studied. The effects of NH4OH concentration, reaction time, and temperature on both biomass recovery and composition of processed samples (including nucleic acid and protein contents) were studied. The results obtained were used to develop empirical models providing a quantitative interpretation of the interrelationships among the variables involved. Additional discussion of the reaction selectivity is provided. Under selected conditions, 96% of nucleic acid removal was achieved with 88% protein recovery. The treated cells were high in vitro digestibility and showed an amino acid profile similar to that of untreated biomass.

Index Entries

Nucleic acids removal single-cell protein 


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  1. 1.
    Selim, M. H., Elshafei, A. M., and El-Diwany, A. I. (1991),Biores. Technol. 36, 157–160.CrossRefGoogle Scholar
  2. 2.
    Kilhberg, R. (1972),Ann. Rev. Microbiol. 26, 427–466.CrossRefGoogle Scholar
  3. 3.
    Roth, F. X. (1980),Animal Res. Dev. 12, 7–19.Google Scholar
  4. 4.
    Waslien, C. I., Calloway, D. H., and Margen, S. (1968),Am. J. Clin. Nutr. 21, 892–897.Google Scholar
  5. 5.
    Edozien, J. C., Udo, U. U., Young, V. R., and Scrimshaw, N. S. (1970),Nature 228, 180.CrossRefGoogle Scholar
  6. 6.
    FAO/WHO/UNICEF (1970), Single Cell Protein, Protein Advisory Group, Rep. 4.Google Scholar
  7. 7.
    Hedenskog, G. and Enninghaus, L. (1972),Biotechnol. Bioeng. 24, 447–457.CrossRefGoogle Scholar
  8. 8.
    Hedenskog, G. and Mogren, H. (1973),Biotechnol. Bioeng. 25, 129–142.CrossRefGoogle Scholar
  9. 9.
    Newell, K. A., Robbins, E. E., and Seeley, R. D. (1975), US Patent 3,867,255.Google Scholar
  10. 10.
    Otero, M. A. and Cabello, A. J. (1980),Biotechnol. Lett. 2, 379–384.CrossRefGoogle Scholar
  11. 11.
    Barreto, T. J., Salva, T. J. G., Baldini, V. L., Papini, R. S., and Sale, A. M. (1989),Proc. Biochem. 10, 167–171.Google Scholar
  12. 12.
    Alvarez, R. and Enriquez, A. (1988),Appl. Microbiol. Biotechnol. 20, 208–210.Google Scholar
  13. 13.
    Otero, M. A., Gonzalez, A. C., Bueno, G. E., and Garcia Revilla, J. L. (1982),Biotech. Lett. 4, 149–152.CrossRefGoogle Scholar
  14. 14.
    Gibert, E. (1986),Int. Congr. Biochem. Eng. 464-468. Google Scholar
  15. 15.
    Damodaran, S. (1986),J. Agric. Food Chem. 34, 26–30.CrossRefGoogle Scholar
  16. 16.
    Reddy, G. U., Ohshima, M., and Nishimura, T. (1990),Jpn. J. Zootech. Sci. 61, 945–951.Google Scholar
  17. 17.
    Maul, S. B., Sinskey, A.J., and Tannenbaum, S. R. (1970),Nature 228, 181.CrossRefGoogle Scholar
  18. 18.
    Cunningham, L., Catlin, B. W., and Privat de Garilhe, M. (1956),J. Am. Chem. Soc. 78, 4642–4648.CrossRefGoogle Scholar
  19. 19.
    Cunningham, L. (1958a),Ann. NY Acad. Sci. 81–82.Google Scholar
  20. 20.
    Cunningham, L. (1958b),J. Am. Chem. Soc. 80, 2546–2552.CrossRefGoogle Scholar
  21. 22.
    Alexander, M., Heppel, L. A., and Hurwitz, J. (1961),J. Biol. Chem. 236, 3014–3019.Google Scholar
  22. 22.
    Schlenk, I. and Dainko, J. L. (1965),J. Bacteriol. 89, 13–18.CrossRefGoogle Scholar
  23. 23.
    Castro, A. C., Sinskey, A. J., and Tannenbaum, S. R. (1971),Appl. Microbiol. 22, 422–427.Google Scholar
  24. 24.
    Rucka, M. and Turkiewicz, B. (1989),Appl. Biochem. Biotechnol. 22, 119–127.CrossRefGoogle Scholar
  25. 25.
    Sanchez-Montero, J. M., Sinisterra, J. V., and Ballesteros, A. (1989),Appl. Biochem. Biotech. 22, 205–214.Google Scholar
  26. 26.
    Martinez, M. C., Sanchez Montera, J. M., Sinisterra, J. V., and Ballesteros, A. (1990),Biotechnol. Appl. Biochem. 12, 643–652.Google Scholar
  27. 27.
    De Groot, A. P. and Slump, P. (1967),J. Nutrition 98, 45–56.Google Scholar
  28. 28.
    Shetty, J. K. and Kinsella, J. E. (1980),J. Agric. Food Chem. 28, 798–792.CrossRefGoogle Scholar
  29. 29.
    Lindbloom, M. (1977),Biotechnol. Bioeng. 19, 199–203.CrossRefGoogle Scholar
  30. 30.
    Herbert, D., Phipps, P. J., and Strange, R. E. (1971),Methods Microbiol. 5B, 249–300.Google Scholar
  31. 31.
    Vázquez, D., Lage, M. A., and Parajó, J. C. (1992),J. Chem. Tech. Biotechnol. 54, 63–74.Google Scholar

Copyright information

© Humana Press Inc 1995

Authors and Affiliations

  • J. C. Parajó
    • 1
  • V. Santos
    • 1
  • H. Domínguez
    • 1
  • M. Vázquez
    • 1
  1. 1.Department of Chemical EngineeringUniversity of VigoOrenseSpain

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