dc.description.abstract | Bacterial wilt disease caused by Ralstonia solanacearum is a major constraining
factor in the production of tomatoes in Kenya, leading to an overreliance on
synthetic pesticides. As a result, there is increased research on bio-pesticides as
safer alternatives. The present study, therefore, characterized and evaluated in
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European Journal of Applied Sciences (EJAS) Vol. 10, Issue 2, April-2022
Services for Science and Education – United Kingdom
vitro antibacterial activity of essential oils from Tithonia diversifolia leaves and
flowers against R. solanacearum. Hydrodistilled essential oils were characterized
through Gas Chromatography-Mass spectrometry (GC-MS) while functional groups
were confirmed using Fourier Transform Infrared Spectroscopy (FT-IR).
Antibacterial activity was performed using the disc diffusion method and minimum
inhibitory concentration evaluated using broth dilution. Hydrodistilled leaves of T.
diversifolia yielded 0.18 + 0.08 % (v/w); 0.10 + 0.07 % w/w as compared to 0.15 +
0.09 % (v/w); 0.08 + 0.03 % w/w in the leaves . GC-MS profiling revealed the major
compounds were (Z,Z,Z)-9,12,15- Octadecatrienoic acid ethyl ester(18%), palmitic
acid (16%), spathulenol (12%), Cis- 9,12,15- Octadecatrienoic acid (8.14%),
tetrateracontane (6%) and 1-Octen-3yl-acetate (5.22%) in the leaves ad α-linolenic
acid trimethylester(33%), Z,Z Hexadecadienoic acid(26%), octadecanoic acid
trimethylester (9%), palmitelaidic acid (8.49%), Germacrene D(5.45%), azelaic
acid (5.02%) and caryophyllene oxide (5.00%) in the flowers. Antibacterial activity
showed that T. diversifolia essential oils had mean inhibition zones of 12.61+ 0.22
mm and 11.82 + 0.76 mm from the leaves and flowers respectively, in comparison
to metham sodium which gave inhibition zone of 25.78 ±0.29 mm (p = 0.001). Based
on the results, this study gives credence to T. diversifolia essential oils as viable
antibacterial agents. | en_US |
dc.subject | Vitro, Antibacterial, Activity, Essential Oils, Tithonia, Diversifolia, Leaves, Flowers, Against, Ralstonia, Solanacearum | en_US |