African Journal of
Pharmacy and Pharmacology

  • Abbreviation: Afr. J. Pharm. Pharmacol.
  • Language: English
  • ISSN: 1996-0816
  • DOI: 10.5897/AJPP
  • Start Year: 2007
  • Published Articles: 2293

Full Length Research Paper

Antioxidant and antibacterial constituents from Morus nigra

Ofentse Mazimba1*, Runner R. T. Majinda1 and Daniel Motlhanka2
1Department of Chemistry, University of Botswana, Private Bag 00704, Gaborone, Botswana. 2Department of Basic Sciences, Botswana College of Agriculture, Private Bag 0027, Gaborone, Botswana.
Email: [email protected]

  •  Accepted: 30 May 2011
  •  Published: 30 June 2011

Abstract

The objective of this study was to isolate and characterize the constituents of the localMorus nigra L. (Black mulberry), to compare its constituents with other studied Mulberries and to evaluate its anti-oxidative and anti-bacterial activities. The isolated compounds were identified by comparison of spectral data (UV, IR, MS and NMR) with literature values. The stem bark and wood of M. nigra yielded a stilbenoid oxyresveratrol 1, a 2-arylbenzofuran moracin M2, four isoprenylated flavonoids; cyclomorusin 3, morusin 4, kuwanon C5 and a derivative of kuwanon C6, two tritepenes; betulinic acid 7, α-amyrin acetate 8 and a steroidal saponin β-sitosterol-3-O-β-D-glucoside 9. The phenolic isolates showed moderate DPPH radical scavenging activity (EC50 = 23-135 µgml-1) compared to ascorbic acid (EC50 = 41 µgml-1) after 30 min. Compounds 1, 2 and 4 to 6 showed activities against Staphylococcus aureus,Bacillus subtilisMicrococus flavusStreptococcus faecalisSalmonella abony,Pseudomonas aeruginosa.

 

Key words: Morus nigra, antioxidant, antibacterial, oxyresveratrol, isoprenylated flavonoids.