Investigation of polysaccharide extracts from Iranian and French strains of Agaricus subrufescens against enzymes involved in Alzheimer's disease / Investigación de extractos de polisacáridos de cepas iraníes y francesas de Agaricus subrufescens contra enzimas relevantes para la enfermedad de Alzheimer

In this work, the inhibitory activity of a wide range of polysaccharide extracts from two Iranian and French strains of Agaricus subrufescens were evaluated toward acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Among them, two extracts S9 and S'7 obtained from Iranian and French strains under different extraction conditions showed selective AChE inhibitory activity with IC50 values of 154.63 and 145.43 µg/mL, respectively. It should be noted that all extracts from both strains demonstrated no BChE inhibitory activity. S9 and S'7 were also tested for their effect on amyloid beta (Aß) aggregation, antioxidant activity, and neuroprotectivity. Their activity against Aß aggregation was comparable to that of donepezil as the reference drug but they induced moderate antioxidant activity by DPPH radical scavenging activity and negligible neuroprotectivity against Aß-induced damage.

En este trabajo, se evaluó la actividad inhibitoria de acetilcolinesterasa (AChE) y butirilcolinesterasa (BChE) para varios extractos de polisacáridos de dos cepas iraníes y francesas de Agaricus subrufescens. Los extractos más potentes mostraron valores de IC50 de 154,63 y 145 µg/ml para las cepas iraní (S9) y francesa (S'7), respectivamente, las cuales se obtuvieron de diferentes condiciones de extracción; sin embargo, todos los extractos no mostraron actividad inhibitoria de BChE. Además, S9 y S'7 se probaron para determinar su efecto sobre la agregación de beta-amiloide (Aß), así como su actividad antioxidante y neuroprotectora. Su actividad inhibitoria de la agregación de Aß fue comparable con donepezil, fármaco de referencia, pero indujeron una actividad antioxidante moderada, medida mediante la captación de radicales DPPH, y una neuroprotectora insignificante contra el daño inducido por Aß.

A phylogenetic and morphological overview of sections Bohusia, Sanguinolenti, and allied sections within Agaricus subg. Pseudochitonia with three new species from France, Iran, and Portugal.

The genus Agaricus was recently rearranged to accommodate numerous tropical taxa. Accordingly, the genus was split into six subgenera and 22 sections of which 12 are included in A. subg. Pseudochitonia. Preliminary data indicated that three putative new species belong to this subgenus. Our objectives were to describe these species, to determine to which sections they belong, and to experience the interest of some traditional traits in this new context. We morphologically described Agaricus coniferarum from France and Portugal, Agaricus iranicus from Iran, and Agaricus lusitanicus from Portugal. Multi-gene phylogenetic analyses based on ITS, LSU, and tef1 sequence data of representatives of the 12 sections clearly indicated that A. coniferarum and A. lusitanicus are placed in Agaricus sect. Bohusia, while A. iranicus is in A. sect. Sanguinolenti. Incidentally, we replaced the illegitimate name Agaricus magnivelaris by Agaricus fiardianus. In a phylogenetic tree, based on all available ITS sequence data and focussing on six related sections, we examined the phylogenetic distribution of various characters. The intensity of red discolouration when the sporocarp is rubbed or cut appeared as a phylogenetically weak informative trait. We propose a determination key leading to a group of three hardly distinguishable sections (Bohusia, Nigrobrunnescentes, and Sanguinolenti).