Abstract:
Expanding of the spectrum of transition metal coordination complexes and their application as regulators of the biosynthetic process in fungi allows highlighting the compounds with important biological properties able to increase the amylases synthesis. The influence of some heterometallic coordination compounds of Ba(II), Sr(II), Ca(II) with Co(II) and polydentate ligand on the amylolytic activity of the fungal strain Aspergillus niger CNMN FD 06 - producer of amylases was evaluated. The stimulatory effect of the coordination compounds of Ba(II) and Sr(II) in the concentration of 5 mg/L and the reduction of the cultivation cycle by 24 hours (from 6 to 5 days) were established. Thus, the coordination compound of barium [Ba(L)3-μ-(NCS)2-Co(NCS)2] in the optimal concentration intensified the biosynthesis of exocellular amylases in the micromycete Aspergillus niger CNMN FD 06, the enzymatic activity on 5th day of cultivation being by 35.6% higher than maximal value of the control established in the 6th day of cultivation (100.50 u/ml, compared to 73.77 u/ml in the control). The compound [Sr(L)3] [Co(SCN)4] showed a similar effect, the amilolytic activity exceeding the maximal value of the control by 51.0% (111.42 u/ml compared to 73.77 u/ml).