Selected publications for last five years:

  1. Uzunova, K., Vasileva, A., Kambourova, M., Ivanova, V., Spasova, D., Mandeva, R., Derekova, A., Tonkova, A. (2001). Production and properties of a bacterial thermostable exo-inulinase. Z. Naturforsch. 56c, 1022-1028.
  1. Kambourova, M., Tangney, M., Priest, F.G. (2001). Regulation of polyglutamic acid synthesis by glutamate in Bacillus licheniformis and Bacillus subtilis. Appl. Environ. Microbiol. 67 (2), 1004-1007.
  1. Uzunova, K., Vassileva, A., Ivanova, V., Spasova, D., Tonkova, A. (2002). Thermostable exo-inulinase production by semicontinuous cultivation of membrane-immobilized Bacillus sp. 11 cells. Process Biochemistry 37, 863-868.
  1. Samuneva, B., Kadiyska, E., Djambaski, P., Dobreva, E., Bojadjieva, I., Kabaivanova, L. (2002). Sol-gel Synthesis of Glassy Hybrid Matrices for Cell Immobilization. Glass Science and Technology, 75-C2, p. 434-437.
  1. Kambourova, M., Kirilova, N., Mandeva, R., Derekova, A. (2003). Purification and properties of thermostable lipase from a thermophilic Bacillus stearothermophilus MC 7. J. Mol. Catal. B, 22, 307-313.
  1. Vassileva, A., Burhan, N., Beschkov, V., Spasova, D., Radoevska, S., Ivanоva, V.,

Tonkova, A. (2003). Cyclodextrin glucantransferase production by free and agar gel immobilized cells of Bacillus circulans ATTC 21783. Process Biochem., 38, 1585-1591.

  1. Groudieva, T., Kambourova, M., Yusef, H., Royter, M., Grote, R., Trinks, H., Antranikian, G. (2004). Diversity and cold-active hydrolytic enzymes of culturable bacteria associated with Arctic sea ice, Spitzbergen. Extremophiles v.8, No 6, 475-488.
  1. Kabaivanova, L., Dobreva, E., Dimitrov, P., Emanuilova, E. (2005). Immobilization of cells with nitrilase activity from a thermophilic bacterial strain. J. Ind. Microbiol. Biotechnol. 32,7-11.
  1. Vassileva, A., Beschkov, V., Ivanova, V., Tonkova, A. (2005). Continuous cyclodextrin glucanoransferase production by free and immobilized cells of Bacillus circulans ATCC 21783 in bioreactors. Process Biochem., 40, 3290-3295.
  1. Chernev, G., Samuneva, B., Djambaski, P., Salvado I.M., Fernandes, M.H., Kabaivanova, L. (2005). Silica Nanocomposites containing Polyacrylamide gel. Glass Technol. 46/2 p.175-178.
  1. Chernev, G., Samuneva, B., Djambaski, P., Salvado, L.M.M., Kabaivanova, L., Dobreva, E., Emanuilova, E. (2005). Whole living cell entrapment in nanomaterials for 4- cyanopyridine biodegradation XIII Intern. Workshop Bioencaps, Kingstone, Ontario (Canada) June 24-26, 57–60.
  2. Derekova, A., Sjoholm, C., Mandeva, R., Michailova, L., Kambourova, M. (2006). Biosynthesis of a thermostable gellan lyase by newly isolated and characterized strain of Geobacillus stearothermophilus 98. Extremophiles v. 10, No 4, 321-326.
  1. Kambourova, M., Mandeva, R., Fiume, I., Maurelli, L., Rossi, M., Morana, A. (2006). Hydrolysis of xylan at high temperature by co-action of the xylanase from Anoxybacillus flavithermus BC and the beta-xylosidase/alpha-arabinosidase from Sulfolobus solfataricus Oalpha. J. Appl. Microbiol. (in press).
  1. Tonkova, A. (2006). Microbial starch converting enzymes of the α-amylase family. In: Microbial Biotechnology in Horticulture (Ray, R.C. and Ward, O.P., eds.), v. 1, pp.421-472. Sci Publ. Inc., Enfield, NH, USA.
  1. Kabaivanova, L., Dobreva, E., Emanuilova, E., Chernev, E., Samuneva, B., Solvado, I. (2006).Synthesis, structure and application of new hybrid nanomaterials for cell immobilization. Minerva Biotechnologica 18.

Main achievements

A moderate thermophilic bacterial strain Bacillus sp. UG-5B with benzonitrilase activity was isolated from polluted industrial waters. The benzonitrile degradation was realized via nitrilase pathway. Due to the high enzyme thermostability of free or immobilized cells as well as the broad substrate specificity, the isolated strain, Bacillus sp. UG-5B could have a potential application in chemical synthesis or various detoxification processes.

An effective synthesis of cyclodextrin glucanotransferase was realized by magnetic biocatalysts containing cells of Bacillus circulans ATCC 21783 and enzyme with a high specific activity was obtained.

New obligate alkalophilic Bacillus strains were isolated from Bulgarian habitats and successfully used for cyclodextrin glucanotransferase production.

A new isolated bacterial strain representing novel species, Anoxybacillus rupiensis, was isolated from Bulgarian hot spring.

The originally isolated from Bulgarian hot spring Bacillus stearothermophilus strain was described as the only producer of thermostable gellan lyase reported up to now. Its thermostability determines the possibility for running industrial processes at temperature higher than 60°C in which temperature gellan is soluble.