Introduction of marine-derived Streptomyces sp. UTMC 1334 as a source of pyrrole derivatives with anti-acetylcholinesterase activity.

AIM: Alzheimer's disease (AD) is the most common cause of dementia. The acetylcholinesterase (AChE) inhibitors are the most viable therapeutic target for its symptomatic treatment. The present study was aimed at exploring anti-AChE metabolite producing marine Actinobacteria.

METHODS AND RESULTS: Of 220 isolates, 34 Actinobacteria extracts were tested for the presence of AChE inhibitors. The obtained results showed that bacterial strain UTMC 1334, inhibited AChE activity in a dose-dependent manner (IC50  = 0·36 ± 0·019 mg ml-1 ). Based on anti-oxidant and cytotoxicity studies, the most potent extract was able to scavenge DPPH radicals with an IC50 value of 45·67 μg ml-1 with the least cytotoxicity. The GC-MS analysis demonstrated that the mentioned activities could be related to pyrrole-derived compounds as were found the predominant constituents in the extract. The most active extract belonged to the strain that shows 99·41% similarity with Streptomyces lateritius based on 16S rRNA gene sequencing.

CONCLUSIONS: Our results show anti-AChE activity is prevalent in marine Actinobacteria, and even in rather comparable prevalence with the antibiotics.

SIGNIFICANCE AND IMPACT OF THE STUDY: This study highlights that exploring new lead anti-AChE compounds may result in discovering novel adjuvant candidates with potency in the treatment of cognitive diseases such as AD.