Eco-friendly bio-larvicidal and antimicrobial activity of isolated bioactive compound from Kurthia gibsonii (Bacillales)

Abstract

The targeted organisms include mosquito vectors, bacterial pathogens and non-targeted organisms. Preliminary mosquito larvicidal activity was conducted using cell-free supernatants (CFSs) from 11 gut bacteria. Among them, the bacterium SS11 exhibited promising results and was identified as Kurthia gibsonii based on its 16S rRNA sequence (1350 bp). The diethyl ether extract (DEE) of K. gibsonii demonstrated significant larvicidal effects, with LC50 values of 5.59 µL/mL and 8.59 µL/mL for 3rd instar larvae of Aedes aegypti and 2nd instar larvae of Anopheles stephensi, respectively. Analysis of the DEE using FT-IR, and GC-MS revealed the presence of 16 functional groups, and 7 bioactive compounds, respectively. A molecular docking study identified GC-MS compounds against odorant receptors from A. aegypti and odorant-binding proteins from A. stephensi was performed to assess the interaction and binding affinity. Overall, these findings suggest that the bioactive compounds 2, 4, 6-tribromoaniline from the DEE of K. gibsonii hold potential as an environmentally compatible alternative for biocontrol purposes, and compounds 9-tricosene and didecyl phthalate can be used for mosquito traps.

Graphical Abstract

Keywords:

• Mosquito-larvicidal activity
• molecular docking
• in-vitro assay
• FTIR
• GC-MS
• 2D-electrophoresis

Acknowledgements

We thank Periyar University for the extended facility, and special thanks are due to the UGC, New Delhi, for the grant of BSR-Faculty Fellowship to PP (F.18-1/2011 (BSR), 26.06.2018).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the UGC, New Delhi, for the grant of BSR-Faculty Fellowship.