In vitro antibacterial activity of traditionally used medicinal plants against Xanthomonas campestris pv. musacearum in Ethiopia

Abstract

Abstract. Yemata G, Desta B, Fetene M. 2019. In vitro antibacterial activity of traditionally used medicinal plants against Xanthomonas campestris pv. musacearum in Ethiopia. Biodiversitas 20: 555-561. In Ethiopia, traditional medicinal plants have long been used to treat human and livestock ailments. Nevertheless, studies about the use of these plant extracts to control crop diseases are scarce. Therefore, the aim of the present study was to evaluate the antibacterial activity of traditionally used medicinal plants against Xanthomonas campestris pv. musacearum (Xcm). The bioactive chemicals from leaf samples were drawn using methanol by maceration method. Total phenolic content of the extracts was determined by Folin Ciocalteau reagent. The antibacterial activity of leaf extracts was evaluated by disc diffusion method. The phytochemical analysis revealed the presence of alkaloids, flavonoids, phenolic compounds, terpenoids, tannins and saponins. Extracts with higher total phenolic content had greater antibacterial activity. The extract of each species showed antibacterial activity against Xcm on a dose dependent manner. Significant differences were recorded between species and test concentrations. The extract of Bersama abyssinica exhibited the strongest antibacterial activity at 200 mg/mL followed by Ricinus communis, Eucalyptus citriodora and Acokanthera schimperi. At lower test concentrations, extracts of E. citriodora and R. communis revealed higher antibacterial activity. Moreover, these species had lower bacteriostatic and bactericidal concentrations. The results showed the potential potency of E. citriodora and R. communis leaf extracts in controlling enset bacterial wilt. However, further studies on the identification of chemical compounds and in vivo evaluation of the extracts are recommended.

In vitro inhibition of Xanthomonas spp. by lemon-scented gum extracts

“…Studies of C. citriodora extracts on the in vitro inhibition of Xanthomonas spp. are less frequent, although Yemata et al (2019) have evaluated the effect of extracts (dry powdered leaves macerated in methanol) of this plant on X. citri pv. musacearum (causing agent of bacterial wilt in cotton) and, corroborating the results of the present work, they observed that lower concentrations of the extract also revealed greater antibacterial activity.…”

“…malvacearum (RASHID et al, 2016). In this same sense, Yemata et al (2019) evaluated the effect of C. citriodora to X. citri pv. musacearum.…”

Antibacterial Activity and Flavonoids Content of Artemisia cina Berg. ex Poljakov Ethyl Acetate Extracts

“…Each isolate in the NA slope medium was taken with an inoculating loop and diluted with physiological saline solution. The turbidity of the bacterial suspension was adjusted to the density of 0.5 McFarland standards, which equals to 1.5 × 108 CFU/ml (Sutton, 2011;Yemata et al, 2019). The bacterial suspension was then taken as much as 100 µl and evenly spread on previously prepared NA plates.…”

Antibacterial Activity and Secondary Metabolite Content of Polyploid Mutant of Artemisia cina Berg ex Poljakov

“…The value of absorbance 0.08 -0.1 equivalent to the density of 0.5 McFarland standards [16]. The bacterial population at 0.5 McFarland standards is approximately equal to 1.5 × 10 8 CFU/ml (Yemata et al, 2019). The bacterial suspension that has been adjusted their turbidity was taken as much as 100 microliters and evenly inoculated on previously prepared NA plates.…”

“…The complex mixture of secondary metabolites in plant crude extract is attributed to the role as effective modulators of related cellular processes viz immune response, mitosis, apoptosis, signal transduction, and key events affect in the pathogenic process [24,25]. Plants have a great ability to produce secondary metabolites such as phenolics, alkaloids, terpenoids, essential oils, lectins, and others [26].…”