INFLUENCE OF BIOTIC STRESS ON THE CONTENT OF PROTOBERBERINE ALKALOIDS IN THE SUSPENSION CULTURE OF <i>THALICTRUMMINUS</i> L. CELLS
We studied the effect of biotic stress on the biosynthesis of protoberberine alkaloids in a suspension culture of Thalictrum cells minus L. The growth of the cell culture under these cultivation conditions was continued for 3 weeks. The cell mass by this time reached 17,6±0,9 g/l, the content of protoberberine alkaloids in the culture fluid 19,7±0,1 mg/l. This amounted to 90,7±0,5 % of all protoberberine alkaloids, the rest was contained in the cells. Aspergillus niger fungi and an unidentified fungus isolated after contamination served as elicitors. Live mycelium was infected at 0 (start of culture growth) and 10 days (mid-growth cycle) of suspension culture cultivation. The alkaloids were evaluated in the first three days after infection and by the 17<sup>th</sup> day of cell culture growth, which corresponded to the subculture cycle. After infection on day 0 of cultivation, differences from control were observed on the second and third day after infection. A decrease in the content of alkaloids by 1,8-3,1 times after infection with Aspergillus niger and on the second day by 2,5 times after infection with an unidentified fungus.By the third day, after infection with an unidentified fungus, on the contrary, there was an increase of 1,9 times. After infection on the 10th day of cultivation, there were no changes in alkaloids in the case of an unidentified fungus. After infection with Aspergillus niger, a quick reaction was noted during the first two hours and intensifying during the first day (induction phase of stress). During this time, there was an increase in the content of alkaloids in 2 and 3 times, respectively. The next phase of stress adaptation was accompanied by a decrease in the content of alkaloids to the control level (second and third days) and even lower by the 17<sup>th</sup> day of cultivation. Thus, the sensitivity of the Thalictrum minus cell culture to Aspergillus niger infection was revealed. The duration of the induction phase of the stress reaction (from two to 24 hours) and stress adaptation from two to 17 days were revealed. The optimal age for detecting a stress reaction was 10 days of culturing a suspension culture of Thalictrum minus L. cells.