Anti-acetylcholinesterase activity and antioxidant properties of extracts and fractions of Carpolobia lutea

Pharm Biol. 2017 Dec;55(1):1875-1883. doi: 10.1080/13880209.2017.1339283.

Abstract

Context: There is an unmet need to discover new treatments for Alzheimer's disease. This study determined the anti-acetylcholinesterase (AChE) activity, DPPH free radical scavenging and antioxidant properties of Carpolobia lutea G. Don (Polygalaceae).

Objective: The objective of this study is to quantify C. lutea anti-AChE, DPPH free radical scavenging, and antioxidant activities and cell cytotoxicity.

Materials and methods: Plant stem, leaves and roots were subjected to sequential solvent extractions, and screened for anti-AChE activity across a concentration range of 0.02-200 μg/mL. Plant DPPH radical scavenging activity, reducing power, and total phenolic and flavonoid contents were determined, and cytotoxicity evaluated using human hepatocytes.

Results: Carpolobia lutea exhibited concentration-dependent anti-AChE activity. The most potent inhibitory activity for the stem was the crude ethanol extract and hexane stem fraction oil (IC50 = 140 μg/mL); for the leaves, the chloroform leaf fraction (IC50 = 60 μg/mL); and for roots, the methanol, ethyl acetate and aqueous root fractions (IC50 = 0.3-3 μg/mL). Dose-dependent free radical scavenging activity and reducing power were observed with increasing stem, leaf or root concentration. Total phenolic contents were the highest in the stem: ∼632 mg gallic acid equivalents/g for a hexane stem fraction oil. Total flavonoid content was the highest in the leaves: ∼297 mg quercetin equivalents/g for a chloroform leaf fraction. At 1 μg/mL, only the crude ethanol extract oil was significantly cytotoxic to hepatocytes.

Discussion and conclusions: Carpolobia lutea possesses anti-AChE activity and beneficial antioxidant capacity indicative of its potential development as a treatment of Alzheimer's and other diseases characterized by a cholinergic deficit.

Keywords: Alzheimer's disease; Anti-acetylcholinesterase; Carpolobia lutea; antioxidant.

Publication types

  • Comparative Study

MeSH terms

  • Acetylcholinesterase / chemistry
  • Acetylcholinesterase / metabolism
  • Animals
  • Antioxidants / adverse effects
  • Antioxidants / chemistry
  • Antioxidants / isolation & purification
  • Antioxidants / pharmacology*
  • Cell Survival / drug effects
  • Cholinesterase Inhibitors / adverse effects
  • Cholinesterase Inhibitors / chemistry
  • Cholinesterase Inhibitors / isolation & purification
  • Cholinesterase Inhibitors / pharmacology*
  • Drug Discovery*
  • Flavonoids / analysis
  • Flavonoids / isolation & purification
  • Flavonoids / pharmacology
  • Free Radical Scavengers / isolation & purification
  • Free Radical Scavengers / pharmacology
  • Hep G2 Cells
  • Hepatocytes / drug effects*
  • Humans
  • Male
  • Nerve Tissue Proteins / antagonists & inhibitors
  • Nerve Tissue Proteins / metabolism
  • Nootropic Agents / analysis
  • Nootropic Agents / chemistry
  • Nootropic Agents / isolation & purification
  • Nootropic Agents / pharmacology
  • Phenols / analysis
  • Phenols / isolation & purification
  • Phenols / pharmacology
  • Plant Extracts / adverse effects
  • Plant Extracts / chemistry
  • Plant Extracts / isolation & purification
  • Plant Extracts / pharmacology*
  • Plant Leaves / chemistry
  • Plant Oils / adverse effects
  • Plant Oils / chemistry
  • Plant Oils / isolation & purification
  • Plant Oils / pharmacology*
  • Plant Roots / chemistry
  • Plant Stems / chemistry
  • Polygalaceae / chemistry*
  • Rats, Inbred F344

Substances

  • Antioxidants
  • Cholinesterase Inhibitors
  • Flavonoids
  • Free Radical Scavengers
  • Nerve Tissue Proteins
  • Nootropic Agents
  • Phenols
  • Plant Extracts
  • Plant Oils
  • Acetylcholinesterase