Chemical composition and antimicrobial activities of wood vinegars from carambola, coconut shells and mango against selected plant pathogenic microorganisms

ABSTRACT

Aims@#This work aimed to evaluate the antimicrobial activities of three different sources of wood vinegars obtained from pyrolysis of carambola (Averrhoa carambola), coconut shells (Cocos nucifera) and mango (Mangifera indica) and to identify their chemical composition. @*Methodology and results@#Agar well diffusion technique was employed to assay the antifungal activity of the wood vinegars against Fusarium oxysporum, Colletotrichum gleosporoides, and Pestalotiopsis microspora and disc diffusion technique for antibacterial screening against Ralstonia solanacearum. The chemical compositions of these wood vinegars were also analyzed using GC-MS by employing the headspace technique. All wood vinegars exhibited antimicrobial activity against tested pathogens. Wood vinegar from carambola exhibited the most promising antimicrobial effect followed by coconut shells and mango. The GC-MS analysis revealed the wood vinegars from coconut shells, carambola, and mango are different in the chemical composition and active compounds. Major compounds identified in coconut shells are furfural, phenol, benzofuran, acetic acid, hexanal, ethanone, and formic acid. In carambola, the main compounds are furfural, imidazole, 3-pyridinecarboxaldehyde, benzaldehyde, phenol, benzofuran, indene, acetic acid, indazole, naphthalene, cyclohexanecarboxylic acid, palmitamide, palmitic acid, heptadecanenitril, and sterylamide. Meanwhile, the main chemical compounds in the pruning of mango-based vinegar consist of toluene, furfural, imidazole, annulene, benzaldehyde, phenol, carbamic acid, acetic acid, naphthalene, heptadecanenitril, and stearylamide.@*Conclusion, significance and impact of study@#It is suggested that wood vinegar from carambola, coconut shells, and mango is a promising antimicrobial agent in plant disease control, showing good potential for inhibition of selected plant pathogenic microorganisms.