Phenolic composition, antioxidant activity, anticholinesterase potential and modulatory effects of aqueous extracts of some seaweeds on β-amyloid aggregation and disaggregation

Pharmaceutical Biology

Anthony I. Okoh¹  Tosin A. Olasehinde²  Ademola O. Olaniran³ 

[1] Department of Biochemistry and Microbiology, Applied and Environmental Microbiology Research Group (AEMREG), University of Fort Hare, Alice, South Africa;SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, South Africa;Department of Biochemistry and Microbiology, Applied and Environmental Microbiology Research Group (AEMREG), University of Fort Hare, Alice, South Africa;SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, South Africa;Food Technology Department, Nutrition and Toxicology Division, Federal Institute of Industrial Research Oshodi, Lagos, Nigeria;Discipline of Microbiology, School of Life Sciences, College of Agriculture, Engineering and Science, University of Kwazulu-Natal, Durban, South Afric;

关键词: Alzheimer’s disease;    cholinesterases;    β-amyloid peptide;   

DOI  :  10.1080/13880209.2019.1634741

来源: Taylor & Francis

【 摘 要 】

Context: Seaweeds contain bioactive compounds with different biological activities. They are used as functional ingredients for the development of therapeutic agents to combat degenerative diseases.Objective: This study investigated the phenolic composition, antioxidant activity, cholinesterase inhibitory and anti-amyloidogenic activities of aqueous extracts of Gracilaria beckeri (J.Agardh) Papenfuss (Gracilariaceae) (RED-AQ), Ecklonia maxima (Osbeck) Papenfuss (Lessoniaceae) (ECK-AQ), Ulva rigida (C.Agardh) Linnaeus (Ulvaceae) (URL-AQ) and Gelidium pristoides (Turner) Kützing (Gelidiaceae) (GEL-AQ).Materials and methods: Phenolic composition of the seaweed extracts was determined using liquid chromatography mass spectrometry. Radical scavenging and metal chelating activities were assessed in vitro. The effect of the extracts (21–84 µg/mL) on acetylcholinesterase and butyrylcholinesterase activities were also investigated using an in vitro colorimetric assay. Transmission electron microscope and thioflavin-T fluorescence assay were used to examine the anti-amyloidogenic activities of the extracts.Results: Phloroglucinol, catechin, epicatechin 3-glucoside were identified in the extracts. ECK-AQ (IC50=30.42 and 280.47 µg/mL) exhibited the highest OH• scavenging and metal chelating activities, while RED-AQ (41.23 and 334.45 µg/mL) exhibited the lowest. Similarly, ECK-AQ (IC50 = 49.41 and 52.11 µg/mL) exhibited higher inhibitory effects on acetylcholinesterase and butyrylcholinesterase activities, while RED-AQ (64.56 and 63.03 µg/mL) showed the least activities. Rapid formation of β-amyloid (Aβ1-42) fibrils and aggregates was observed in electron micrographs of the control after 72 and 96 h. The reduction of Aβ1-42 aggregates occurred after co-treatment with the seaweed extracts.Discussion and conclusion: ECK-AQ, GEL-AQ, URL-AQ and RED-AQ may possess neuroprotective potential and could be explored for the management of Alzheimer’s disease.

【 授权许可】

CC BY