African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5233

Full Length Research Paper

Bacterial diversity of aMasi, a South African fermented milk product, determined by clone library and denaturing gradient gel electrophoresis analysis

  Renate Døving Osvik1, Sigmund Sperstad1,2, Eva Breines3, Ellinor Hareide3, Jacques Godfroid3,4, Zhigang Zhou5, Pengfei Ren5, Claire Geoghegan6, Wilhelm Holzapfel7 and Einar Ringø1*
  1Faculty of Biosciences, Fisheries and Economics, Norwegian College of Fishery Science, University of Tromsø, N-9037 Breivika, Norway. 2Department of Zoophysiology, Institute of Zoology, University of Kiel, Olshausenstr. 40, 24098 Kiel, Germany. 3Section of Arctic Veterinary Medicine, Department of Food Hygiene, The Norwegian School of Veterinary Science, N-9292 Tromsø, Norway. 4Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa. 5Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, P. R. China. 6Department of Zoology and Entomology, Mammal Research Institute, University of Pretoria, Pretoria, Gauteng, South Africa. 7School of Life Science, Handong Global University, Pohang, South Korea.
Email: [email protected]

  •  Accepted: 26 July 2013
  •  Published: 09 August 2013

Abstract

 

In the present study, we investigated the bacterial diversity of aMasi, a traditional South African fermented milk product, by 16S rRNA clone library and Denaturing Gradient Gel Electrophoresis (DGGE) analysis. Two hundred and eighty two clones from clone library were isolated and identified from aMasi, prepared from the milk of four cows from one herd in the EkuPindiseni Community, North West of Hluhluwe-iMfolozi Park in KwaZulu-Natal Province. The majority of the identified sequences corresponded to lactic acid bacteria (LAB), with the genus Lactococcus as major representative. The speciesLactococcus lactis accounted for 179 of the identified clones. In addition, several species of LactobacillusLeuconostoc and Enterococcus were detected. Furthermore, several clones belonging to AcinetobacterAeromonas and genera within the Enterobacteriaceaewere detected. It is important to note that human pathogens such as Klebsiella pneumoniae were identified in aMasi in the present study. Conversely, zoonotic bacteria such as Brucella abortus and Mycobacterium bovis were not detected in aMasi, although, they are present in the cattle population in the study area. Thirty (30) clones were identified as uncultured bacterial clones. Nine DGGE bands were successfully sequenced, of which four were classified as Llactis with other bands belonging to lactobacilli, Clostridium aciduriciEnterobacter sp., Acinetobacter baumannii and an un-culturable bacterium. Even though there was some discrepancy between the two culture independent methods used to study the bacteriological community in aMasi, a general conclusion can be drawn,Llactis may be considered as the dominant bacterium within a diverse bacterial community in this locally-produced dairy product.

 

Key words: South Africa, aMasi, fermented milk, microbial diversity, clone library, denaturing gradient gel electrophoresis (DGGE).