Antimicrobial activity of several Brazilian medicinal plants against phytopathogenic bacteria

Abstract

What is currently raised as a new approach in the management of plant diseases is the development and formulation of plant based biopesticides. The objective of present study is to evaluate the antibacterial activity of aqueous extracts of twelve species belonging to seven families collected from the Northeast of Brazil against four economically important phytopathogenic bacteria. Antibacterial activities of the aqueous extracts were studied by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Twelve aqueous extracts of twelve species were evaluated. Only three extracts were not active against Ralstonia solanacearum and other three extracts were not active against Xanthomonas campestris pv. campestris. Anadenanthera colubrina var. cebil, Croton pedicellatus and Eugenia brejoensis presented a broad spectrum of the inhibitory effect (MIC 3.12 to 12.5 mg/mL). According to these results, we conclude that the flora in the northeast of Brazil can be regarded as a rich source of plants with antibacterial activity. Therefore, further screening of other plant species, identifying active fractions or metabolites and in vivo application of active extracts are warranted.

ANALYSIS CHEMICAL COMPOUNDS AND ANTIMICROBIAL ACTIVITY OF RED ONION (Allium cepa L.) BULB SKIN EXTRACT

“…It was also reported that phenol as the chemical compound can inhibit the growth of Salmonella thypi and Escherichia coli 23,25 . Cell membrane damage has been reported to have occurred as a result of interacting with plant chemical compounds, for example in phenol compounds have several working mechanisms, including membrane disruption, protein binding, inhibiting protein synthesis, inhibiting enzymes, cell wall destruction, disulfide bridge formation and intercalation with the cell wall and/or DNA 27,28 .…”

“…Alkaloids have intercalation with the cell wall and/or DNA working mechanism 27 . The triterpenoid compound has a membrane disruption mechanism 27,29 .…”

“…Alkaloids have intercalation with the cell wall and/or DNA working mechanism 27 . The triterpenoid compound has a membrane disruption mechanism 27,29 . Antifungal Activity of Extract of Outer Layers of Onion Bulbs (Allium cepa L.) for Candida albicans (CA) ATCC 10231 can be seen in Figure 3.…”

Isolation of active antiphytopathogen compound from extracts of Anadenanthera colubrina var. cebil (Griseb.) Altschul

“…Antibacterial activity, Minimum inhibitory concentrations (MIC) and minimum bactericidal concentration (MBC), in mg.ml -1 , of preparative fractions against selected plant pathogenic bacterial. Given the importance of developing a biopesticide, several studies have been carried out, in search of this objective, thus, a screening carried out by Silva et al [11] with several plants of medicinal importance against several phytopathogens pointed to A. colubrina as an important source of antimicrobial compounds. From this result, a bioguided purification approach was carried out, starting with an extraction following the eluotropic order of solvents and using an in vitro anti-phytopathogenic bioassay.…”

“…cebil (Griseb.) Altschul, popularly known as Angico, belonging to this family, it is widely used in folk medicine because it is related to the antimicrobial properties of its leaves [10,11] . This work aimed to conduct a bioguided study on organic extracts of A. colubrina var.…”