African eggplant (Solanum anguivi Lam.) fruit with bioactive polyphenolic compounds exerts in vitro antioxidant properties and inhibits Ca(2+)-induced mitochondrial swelling.
OBJECTIVE
To evaluate the antioxidant and radical scavenging activities of Solanum anguivi fruit (SAG) and its possible effect on mitochondrial permeability transition pore as well as mitochondrial membrane potential (ΔΨm) isolated from rat liver.


METHODS
Antioxidant activity of SAG was assayed by using 2,2-diphenyl-1-picrylhydrazyl (DPPH), reducing power, iron chelation and ability to inhibit lipid peroxidation in both liver and brain homogenate of rats. Also, the effect of SAG on mitochondrial membrane potential and mitochondrial swelling were determined. Identification and quantification of bioactive polyphenolics was done by HPLC-DAD.


RESULTS
SAG exhibited potent and concentration dependent free radical-scavenging activity (IC50/DPPH=275.03±7.8 μg/mL). Reductive and iron chelation abilities also increase with increase in SAG concentration. SAG also inhibited peroxidation of cerebral and hepatic lipids subjected to iron oxidative assault. SAG protected against Ca(2+) (110 μmol/L)-induced mitochondrial swelling and maintained the ΔΨm. HPLC analysis revealed the presence of gallic acid [(17.54±0.04) mg/g], chlorogenic acid (21.90±0.02 mg/g), caffeic acid (16.64±0.01 mg/g), rutin [(14.71±0.03) mg/g] and quercetin [(7.39±0.05) mg/g].


CONCLUSIONS
These effects could be attributed to the bioactive polyphenolic compounds present in the extract. Our results suggest that SAG extract is a potential source of natural antioxidants that may be used not only in pharmaceutical and food industry but also in the treatment of diseases associated with oxidative stress.
Department of Biochemistry, Adekunle Ajasin University, Akungba, Ondo State, Nigeria; Department of Biochemistry, University of Ado Ekiti, Ekiti State, Nigeria; Postgraduate Programme in Biochemical Toxicology, Department of Chemistry, CCNE, Federal University of Santa Maria, Campus Camobi, Santa Maria, RS, 97105-900, Brazil. Electronic address: sola_eleko@yahoo.com.
Olusola Olalekan
OO
Elekofehinti
Jean Paul
JP
Kamdem
Aline Augusti
AA
Bolingon
Margareth Linde
ML
Athayde
Seeger Rodrigo
SR
Lopes
Emily Pansera
EP
Waczuk
Ige Joseph
IJ
Kade
Isaac Gbadura
IG
Adanlawo
Joao Batista Teixeira
JB
Rocha
D000818:Animals; D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism / Q000494:pharmacology*; D005638:Fruit / Q000737:chemistry*; D007502:Iron Chelating Agents / Q000737:chemistry / Q000494:pharmacology; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008930:Mitochondria, Liver / Q000187:drug effects / Q000378:metabolism; D033681:Mitochondrial Membrane Transport Proteins / Q000378:metabolism; D000083162:Mitochondrial Permeability Transition Pore; D008933:Mitochondrial Swelling / Q000187:drug effects*; D010084:Oxidation-Reduction / Q000187:drug effects; D010539:Permeability / Q000187:drug effects; D010636:Phenols / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D059808:Polyphenols / Q000737:chemistry / Q000494:pharmacology*; D051381:Rats; D032322:Solanum / Q000737:chemistry*
D000975:Antioxidants; D007502:Iron Chelating Agents; D033681:Mitochondrial Membrane Transport Proteins; D000083162:Mitochondrial Permeability Transition Pore; D010636:Phenols; D010936:Plant Extracts; D059808:Polyphenols; D002118:Calcium
Antioxidant activity; HPLC; MPTP; Mitochondrial swelling; Oxidative stress; Polyphenolic compounds; Solanum anguivi fruit