Conclusion and future work

Conclusion

We can conclude that, earthworm and mealworm are ineffective in inhibiting the growth of bacteria in planktonic state. However, we have statistically significant results to show that earthworm and mealworm can prevent the dispersal of established biofilms of E. coli and S. epidermidis as well as P. fluorescens and inhibit the formation of biofilm of E. coli and S. epidermidis. Additionally, earthworm has shown to be the more effective extract compared to mealworm as it is more effective in both dispersing established biofilm as well as inhibiting the formation of biofilm.

Limitations

Some limitations faced in our experiment is the low efficiency of the extracts in removing the formed biofilm. However, it is effective in inhibiting the formation of the biofilm. Also, different batches and ages of mealworm will affect the effectiveness in dispersing established biofilm and inhibiting the formation of biofilm.

Discussions

There are no studies done on effect of earthworm and mealworm on formation of biofilm or formed biofilm. However, there were studies done on the effect of maggot excretion and secretion (ES) on biofilm. It was found that as little as 0.2μg of ES prevented S. aureus biofilm formation and 2 μg of ES rapidly degraded biofilms (van der Plas et.al, 2007)

Application

Biofilm consist of both microbes and their extracellular products, usually polysaccharides. These results in biofouling, a process whereby there are biological desposits when biofilm adhere to surfaces. Biofilm formation causes problems in many branches of industry, such as in industrial water systems and the medical and process industries, resulting in losses in industries and risks to human health. (Mattila-Sandholm & Wirtanen, 2009)

Earthworm and mealworms are easily accessible and readily available. We also have statistically significant results prove that they are effective against biofilm. Hence, they are a viable solution for utilisation in affected industries to remove established biofilms/inhibiting biofilm formation because of the affordability and effectiveness. However, it should be sterilised thoroughly before use.

Future work

Time may be varied to see how changing the time will affect the inhibitory effect of the extract on the biofilms. Also, the amount of extract may be varied to find the optimum amount of extract to inhibit the formation of biofilm as well as the dispersal of established biofilm. We may also experiment our extracts on other strains of bacteria that form biofilm to see if they are a universal solution to combat biofilm.