Phenolic Glycosides and Bioactive Mangifera Indica L. Kernel Extract As Neuroprotective Agents Against LPS-induced Alzheimer's Disease in Rats

The seed kernel wastes generated during the consumption and processing of Mangifera indica L. are generally discarded although their remarkable nutritional phytoconstituents. Aqueous methanol kernel extract was subjected to chromatographic and spectroscopic analyses for the isolation of predominant phenolic com-pounds. In addition, they were quantitatively estimated through HPLC. The isolates were characterized as gallic acid, mangiferin, isomangiferin, and 1,2,3,4,6-penta-O-galloyl-,B-glucose and quantified as 37.48, 40.41, 33.29, and 69.07 mg/g extract, respectively. For the first time, the extract, as well as isomangiferin and pentagalloyl glucose were orally administered for 7 consecutive days in a lipopolysaccharide-induced-neuro-infiammatory Alzheimer's disease mouse model for assessment of memory and cognitive performance. Iso-mangiferin (50 mg/kg) and pentagalloyl glucose (30 mg/kg) increased spatial recognition in the object recognition test by 45.34% and 47.62%, respectively, compared to Alzheimer's mice. Besides, they significantly improved the working memory (% alteration in the Y-maze test). Assessment of the mean amyloid ,B-42 con-centrations revealed a significant reduction in animals treated with 50 & 100 mg/kg kernel extract (40.3 & 65.8%), 50 mg/kg isomangiferin (67.5%), and 30 mg/kg pentagalloyl glucose (57.25%) compared to the amne-sic mice (increased by 276% compared to control). Also, a significant decrease for the same samples in acetyl-cholinesterase levels by 32.28%, 53.14%, 62.41%, and 57.9%, respectively, were detected compared to the Alzheimer's mice (increased by 88.75% compared to control). The neuroprotective effect of mango kernel extract and the isolates support their beneficial effects in restoring cognitive capabilities through anti-amy-loid and anticholinesterase activities. (c) 2023 SAAB. Published by Elsevier B.V. All rights reserved.