Cover Image

Antagonistic effects of Rhamnolipid biosurfactant on larval gut microbes and impact on the growth and development of the silkworm

Mani Kannan, Pattanathu Rahman, Thangarasu Arumugam, Thangaiyan Suganya, Vimalanathan Arunprasanna, Gianluca Tettamanti, Muthukalingan Krishnan


The demand for bio-based insecticides has significantly increased during the last decade due to the contamination of the environment following massive pesticide use. The present study aims at evaluating the insecticidal activity of rhamnolipid (RL) biosurfactant (from 0.01 to 1 %) orally administered to fifth instar larvae of the silkworm, Bombyx mori, a model among Lepidoptera. The bioassay showed that above 0.5% RL caused significant mortality in the larvae and pupae of B.mori. To evaluate the mode of action of RL, we carried out antibacterial activity assays against larval gut microbes of B.mori. Interestingly, a fall of the microbial population and a susceptibility of host beneficial bacterial species, like Bacillus megaterium, Bacterium IMBL3, Enterococcus mundtii and Bacillus cerus, towards RL were observed by using plate sensitive assay and agar well diffusion assay, respectively. The results of the present study confirm that RL cause the breakdown of beneficial interactions between the larval gut and microbes, leading to a high rate of larval mortality due to the digestive upset in the B. mori gut. This work provides a platform of knowledge to set up promising strategies for the biological control of insect pests.

Full Text:



Aktar, M. W., D. Sengupta and A. Chowdhury, 2009. Impact of pesticides use in agriculture: Their benefits and hazards. Interdisciplinary toxicology, 2(1): 1-7.

Awada, S. M., R. S. Spendlove and M. Awada, 2011. Microbial biosurfactants as agents for controlling pests. Google Patents.

Banat, I. M., S. K. Satpute, S. S. Cameotra, R. Patil and N. V. Nyayanit, 2014. Cost effective technologies and renewable substrates for biosurfactants’ production. Frontiers in microbiology, 5: 1-18.

Bergey, D. H., 2001. Bergey's manual® of systematic bacteriology. Springer Science & Business Media.

Bharali, P., J. Saikia, A. Ray and B. Konwar, 2013. Rhamnolipid (rl) from Pseudomonas aeruginosa obp1: A novel chemotaxis and antibacterial agent. Colloids Surfaces B: Biointerfaces, 103: 502-509.

Bharali, P., J. Saikia, A. Ray, B. Konwar and S. B:, 2013. Rhamnolipid (rl) from Pseudomonas aeruginosa obp1: A novel chemotaxis and antibacterial agent. Biointerfaces, 103: 502-509.

Boethling, R., A. Voutchkova-Kostal and P. T. Anastas, 2014. Green processes, volume 9: Designing safer chemicals. John Wiley & Sons.

Bondarenko, O., P. K. Rahman, T. J. Rahman, A. Kahru and A. Ivask, 2010. Effects of rhamnolipids from Pseudomonas aeruginosa ds10-129 on luminescent bacteria: Toxicity and modulation of cadmium bioavailability. Microbial ecology, 59(3): 588-600.

Hammer, O. J., 2001. Past: Paleontological statistics software package for education and data analysis. Palaeontologia electronica, 4, 9p.

Irfan-Maqsood, M. and M. Seddiq-Shams, 2014. Rhamnolipids: Well-characterized glycolipids with potential broad applicability as biosurfactants. Industrial biotechnology, 10(4): 285-291.

Kama, A., A. B. Shaik, C. G. Kumar, P. Mongolla, P. U. Rani, K. Krishna, S. K. Mamidyala and J. Joseph, 2012. Metabolic profiling and biological activities of bioactive compounds produced by Pseudomonas sp. Strain ictb-745 isolated from ladakh, india. Journal of microbiology biotechnology, 22(1): 69-79.

Kannan, M., K. Balakrishnan, G. Sanjeev and M. Krishnan, 2016. Assessment of electron beam irradiation induced proteomic changes and its effect on the development of silkworm, bombyx mori (bombycidae: Lepidoptera). The Journal of basic applied zoology, 73: 32-38.

Kim, S. K., Y. C. Kim, S. Lee, J. C. Kim, M. Y. Yun and I. S. Kim, 2011. Insecticidal activity of rhamnolipid isolated from Pseudomonas sp. Ep-3 against green peach aphid (Myzus persicae). Journal of agricultural food chemistry, 59(3): 934-938.

Kumar, A., S. K. Singh, C. Kant, H. Verma, D. Kumar, P. P. Singh, A. Modi, S. Droby, M. S. Kesawat and H. Alavilli, 2021. Microbial biosurfactant: A new frontier for sustainable agriculture and pharmaceutical industries. Antioxidants, 10(9): 1472.

Nirmala, X., V. Vanishree and M. Krishnan, 1999. Changes in embryonic protein profile and economic characters of bombyx mori (lepidoptera: Bombycidae) following uv irradiation. Indian journal of experimental biology, 37(6): 560-566.

Ochsner, U. A., A. Fiechter and J. Reiser, 1994. Isolation, characterization, and expression in Escherichia coli of the Pseudomonas aeruginosa rhlab genes encoding a rhamnosyltransferase involved in rhamnolipid biosurfactant synthesis. Journal of biological chemistry, 269(31): 19787-19795.

Prem Anand, A. A., S. J. Vennison, S. G. Sankar, D. I. Gilwax Prabhu, P. T. Vasan, T. Raghuraman, C. Jerome Geoffrey and S. E. Vendan, 2010. Isolation and characterization of bacteria from the gut of Bombyx mori that degrade cellulose, xylan, pectin and starch and their impact on digestion. Journal of insect science, 10(1): 107.

Sachdev, D. P. and S. S. Cameotra, 2013. Biosurfactants in agriculture. Applied microbiology biotechnology, 97(3): 1005-1016.

Silva, V. L., R. B. Lovaglio, C. J. Von Zuben and J. Contiero, 2015. Rhamnolipids: Solution against aedes aegypti? Frontiers in microbiology, 6: 88.

Singh, P. and V. Rale, 2022. Applications of microbial biosurfactants in biocontrol management. In: Biocontrol mechanisms of endophytic microorganisms. Elsevier: pp: 217-237.

Subramanian, S., P. Mohanraj and M. Muthuswamy, 2009. Newparadigm in silkworm disease management using probiotic application of streptomyces noursei. Karnataka Journal of Agricultural Sciences, 22(3): 499-501.

Vanishree, V., X. Nirmala, E. Arul and M. Krishnan, 2005. Differential sequestration of storage proteins by various fat body tissues during post-larval development in silkworm, Bombyx mori L. Invertebrate reproduction development, 48(1-3): 81-88.



  • There are currently no refbacks.

Copyright (c) 2022 Mani Kannan, Pattanathu Rahman, Thangarasu Arumugam, Thangaiyan Suganya, Vimalanathan Arunprasanna, Gianluca Tettamanti, Muthukalingan Krishnan

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.

Print ISSN: 2522-6746 : Online ISSN: 2522-6754
1. How to register 
2. How to reset password
2. How to prepare a manuscript before submission 
3. How to submit a paper 
4. How to check the review status of a paper
5. How to check the plagirisim or similarity report