Background: The genus Psychotria and Palicourea are reported as a source of alkaloids and
iridoids, which exhibit biological activities. This study aimed to evaluate antiproliferative and anticholinesterase
activities and quantification of the alkaloids of seven species among the genus found in
Mato Grosso do Sul region in Brazil.
Methods: Concentrations of alkaloids were measured spectrophotometrically. The extracts were submitted
to antiproliferative activity against ten cell lines. The anticholinesterase activity of the extracts
was developed using brain structures of male Wistar rats: cerebral cortex, hippocampus, hypothalamus
and striatum by the Ellman method.
Results: Alkaloids from Psychotria and Palicourea species were quantified which showed values of
47.6 to 21.9 μg/g. Regarding the antiproliferative potential, Palicourea crocea demonstrated selectivity
against the 786-0 cell line (GI50: 22.87 μg/mL). Psychotria leiocarpa inhibited cell growth against
OVCAR-3 (GI50: 3.28 μg/mL), K-562 (GI50: 5.26 μg/mL), HaCaT (GI50: 27.20 μg/mL), PC-3 (GI50:
34.92 μg/mL), MCF-7 (GI50: 35.80 μg/mL) and P. capillacea showed activity against OVCAR-3 (GI50:
2.33 μg/ml) and U251 (GI50: 16.66 μg/ml). The effect of acetylcholinesterase inhibition was more effective
in the hippocampus, demonstrating inhibition for Paliourea crocea, Psychotria deflexa,
P. brachybotrya and P. leiocarpa of 70%, 57%, 50% and 40%, respectively, followed by P.
poeppigiana and P. capillacea, inhibiting 21%, compared to the control.
Conclusion: Herein, the present work showed for the first time, anticholinesterasic and antiproliferative
activities of extracts of Palicourea and Psychotria seem to be mainly associated with the levels of
alkaloids in the leaves of these species.