African Journal of

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12257

Full Length Research Paper

Optimizing DNA isolation protocol for rosemary (Rosemarinus officinalis L) accessions

Zewdinesh Damtew Zigene
  • Zewdinesh Damtew Zigene
  • Wondo Genet Agricultural Research Center, Ethiopian Institute of Agricultural Research, Ethiopia.
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Bizuayehu Tesfaye Asfaw
  • Bizuayehu Tesfaye Asfaw
  • Hawassa University College of Agriculture, P. O. Box 05, Hawassa, Ethiopia.
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Tesfaye Disasa Bitima
  • Tesfaye Disasa Bitima
  • National Biotechnology Research Center, Ethiopian Institute of Agricultural Research, Holeta, Ethiopia.
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  •  Received: 29 July 2019
  •  Accepted: 13 September 2019
  •  Published: 31 October 2019


Rosemary plant is in high demand due to its application in traditional health care, food flavoring, fragrance and pharmaceutical industries. It contains high level of secondary metabolites which are responsible for its beneficial activities. Application of molecular techniques would facilitate the production of these substances and screening of accessions. The isolation of polymerase chain reaction (PCR) amplifiable genomic DNA is a pre-requisite for taking advantage of these technologies. Even though several DNA isolation protocols for plants with high level of secondary metabolites were developed, they may not permit optimal DNA extraction due to chemotypic variation within species. Extracting DNA from different rosemary accessions is a challenging task due to its high level of secondary metabolites. Therefore, this research is conducted with the aim of optimizing a reliable and rapid method suitable for extracting DNA from rosemary plants. The optimized protocol avoids the use of repeated toxic phenols, liquid nitrogen and large polypropylene tube. It is appropriate for both fresh and dry leaf samples. The quality of the obtained DNA was excellent as evident by A260/A280 ratio ranging from 1.7 to 1.89 and the concentration ranged from 195.8 to 2184 ng/µl. The success of this protocol indicated its applicability for other plants with high secondary metabolite contents.


Key words: DNA isolation, secondary metabolites, rosemary, gel electrophoresis, polymerase chain reaction (PCR) amplification.