Morphological and biochemical characterization of endophytic bacteria from selected medicinal plants found at the University of Dar es Salaam, Tanzania

Abstract

Endophytic bacteria are capable of colonising internal tissues of medicinal plants, and producing secondary metabolites (biochemical compounds) of beneficial importance like the ones produced by their host plants. Though Tanzania harbours a wide species of medicinal plants with endophytic bacteria capable of producing such important bioactive substances, research on these bacteria remains scant, which limit their biotechnological applications. This work was undertaken to isolate and document endophytic bacteria from tropical almond, local avocado, banana and blue snake weed plants found at the University of Dar es Salaam, main campus. The study characterised the isolated endophytes based on morphological descriptors and biochemical assays. Furthermore, Principal coordinate analysis (PCoA), Multiple correspondence analysis (MCA), and Hierarchical cluster analysis (HCA) were utilized in assessing the morphological and biochemical relatedness of the isolated endophytic bacteria. A total of 34 bacterial isolates were obtained from root and leaf samples of four medicinal plants and were tentatively identified as belonging to seven genera: Bacillus, Lysinibacillus, Brevibacterium, Curtobacterium, Enterobacter, Microbacterium, and Pseudomonas. While PCoA (recovered from morphological data) did not show any grouping of the studied endophytic bacteria, MCA (recovered from biochemical data) and HCA (recovered from both morphological and biochemical dataset) grouped the bacteria into seven and two groups, respectively. This diversity presents opportunities for discovering novel bioactive compounds that could be utilized for various biotechnological applications. Genetic and secondary metabolites profiling of the isolates is proposed to accurately delineate them to the species or strain level.