Fig 1.
Mass spectra of norharman (A) and harman (B).
Table 1.
Concentration of β-carboline alkaloids (μg/l ± SD) determined by GC-MS in cell-free filtrates of C. coronatus.
Fig 2.
The total ion current (TIC) of harman and norharman extracted from MM (pink) and LB (black) post-incubation media.
Fig 3.
Effect of topical application of harman and norharman on pupation of Galleria mellonella larvae.
1H- harman 750 ppm, 2H- harman 1000 ppm, 3H- harman 1250 ppm. 1N- norharman 750 ppm, 2N- norharman 1000 ppm, 3N- norharman 1250 ppm. The day of administration of the alkaloids (final larval instar day 3) is marked with the arrow. In the 2H sample, 5% of the larvae died. In the remaining groups, all insects passed into the pupal stage.
Fig 4.
Effect of ingestion diet treated with harman and norharman on pupation of Galleria mellonella larvae.
1H- harman 750 ppm, 2H- harman 1000 ppm, 3H- harman 1250 ppm. 1N- norharman 750 ppm, 2N- norharman 1000 ppm, 3N- norharman 1250 ppm. The day of administration of the alkaloids (final larval instar day 3) is marked with the arrow. In the control, 1H and 1N groups, all larvae passed into the pupal stage. In the 2H, 3H, 2N and 3N groups, respectively 80%, 85%, 90% and 85% of larvae passed into the pupal stage.
Fig 5.
Effect of topical harman and norharman application on the adult molt of Galleria mellonella pupae.
1H- harman 750 ppm, 2H- harman 1000 ppm, 3H- harman 1250 ppm. 1N- norharman 750 ppm, 2N- norharman 1000 ppm, 3N- norharman 1250 ppm. Insects received alkaloids on the third day of the final larval instar. In controls and 2N groups, all pupae became adults. In the 1H, 2H, 3H, 1N, and 3N groups, respectively 97%, 95%, 95%, 95% and 95% of pupae became adults.
Fig 6.
Effect of ingestion of harman and norharman with the diet on adult molt of Galleria mellonella pupae.
1H- harman 750 ppm, 2H- harman 1000 ppm, 3H- harman 1250 ppm. 1N- norharman 750 ppm, 2N- norharman 1000 ppm, 3N- norharman 1250 ppm. Insects received alkaloids on the third day of the final larval instar. In control groups, all pupae became adults. In the 1H, 2H, 3H, 1N, 2N and 3N groups, respectively, 90%, 90%, 80%, 90%, 90% and 75% of pupae became adults.
Fig 7.
Serotonin concentration in heads of G. mellonella larvae treated with harman and norharman.
A- One hour after topical application of alkaloids. B- 24 hours after topical application of alkaloids. C- 24 hours after ingestion of food mixed with alkaloids. statistically significant differences as compared to control was marked with the same letters, P≤0.05.
Fig 8.
Effect of harman and norharman on MAO-A concentration in G. mellonella larvae heads.
Data are expressed as mean ± SD. A- One hour after topical application of alkaloids. B- 24 hours after topical application of alkaloids. C- 24 hours after ingestion of food mixed with alkaloids. statistically significant differences as compared to control was marked with the same letters, P≤0.05.
Fig 9.
Effect of harman and norharman on MAO-A and MAO-B activity in the heads of G. mellonella larvae.
Data are expressed as mean ± SD; empty bars- MAO-A activity; hatched bars- MAO-B activity. Data are presented as a percentage of the activity, control was taken as 100%. A-larvae after one hour from topical application. B- larvae after 24 hours from topical application. C- larvae after 24 hours from application with food. statistically significant differences as compared to control was marked with the same letters, P≤0.05.