Viability and morphological changes of Acanthamoeba spp. cysts after treatment with Effective microorganisms (EM)
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Acanthamoeba is a free-living opportunistic protozoan parasite that is found in diverse environments. It can cause keratitis, mostly related to inappropriate use of contact lenses, as well as life threatening diseases including encephalitis, disseminated sinusitis, and skin ulcers. This study investigated morphological changes and fine structures of the cyst form of Acanthamoeba spp. after treatment with effective microorganisms (EM™) using light and scanning electron microscopies. Acanthamoeba cysts treated with 1:2, 1:4, 1:6, and undiluted EM™ showed higher percentages of non-viable cysts than those treated with 1:8, 1:10, 1:100, 1:200, and 1:400 EM™ and at 5 days post-treatment developed from cystic stage to trophozoite stage. Acanthamoeba cysts treated at concentrations of 1:2, 1:4, 1:6, and undiluted EM™ exhibited cytoplasmic clumping and shrinkage of amoeba cells away from cyst walls. The effective EM™ concentration lethal to Acanthamoeba spp. cyst could provide information to monitor the environmental control system.
KeywordsAcanthamoeba spp. Effective microorganisms Viability and morphological changes
We gratefully acknowledge the help and support provided by the staff of the Department of Parasitology, Faculty of Medicine, Siriraj Hospital, Mahidol University. This work was partially supported for publication by the China Medical Board, Faculty of Public Health, Mahidol University, Bangkok, Thailand (Usa Lek-Uthai).
- EM Technology (1998) Effective microorganisms for a sustainable agriculture and environment, EM Tech ProductGoogle Scholar
- Fowler M, Carter RF (1965) Acute pyogenic meningitis probably due to Acanthamoeba spp. a preliminary report. Br Med J 5464:740–742Google Scholar
- Higa T, James P (1994) Beneficial and effective microorganisms for a sustainable agriculture and environment. International Nature Farming Research Center, Atami, Japan, p 7Google Scholar
- Sangakkara UR (2002) The technology of effective microorganisms-case studies of application. Royal Agricultural College, Cirencester, UKGoogle Scholar
- Szymanski N, Patterson RA (2003) Effective microorganisms (EM) and wastewater systems in future directions for on-site systems: best management practice. In: Patterson RA, Jones MJ (eds) Proceedings of on-site’03 conference. Armidale, NSW, Australia, Lanfax Laboratories, pp 347–354Google Scholar
- Visvesvara GS (1980) Free-living pathogenic amoebae. In: Lennette EH, Balows A, Hausler WJ, Truant JP (eds) Manual of clinical microbiology, 3rd edn. American Society for Microbiology, Washington, D.C, pp 704–708Google Scholar