Mohammed Rafiyuddin, Najia Albashir Mahdawi


Acanthamoebae can be easily grown in bacterised cultures, but their growth in axenic media is tedious and many times unsuccessful. We thus experimented with some additives in the conventional axenic medium for growth of various isolates of Acanthamoeba. Addition of Torula yeast RNA was found to significantly enhance the growth of Acanthamoebae in the axenic culture medium.


Acanthamoebae are ubiquitous free‑living amoebae found in the environment and have been isolated from a variety of habitats.[1,2] These have been implicated in causing granulomatous amoebic encephalitis, keratitis, cutaneous and osteocutaneous disease both in immunocompromised and immunocompetent patients.[3]

Acanthamoebae have two stages in their life cycle: an actively diving trophozoite stage and a dormant cyst stage. Acanthamoebae remain alive with bacteria, yeasts, and mammalian cells at optimal cultivation temperatures of 23°C to 37°C.[3,7] These can be easily cultivated either on non‑nutrient agar (NNA) medium or agar medium containing low concentration of nutrients in the presence of living or dead bacteria. However, adapting these amoebae to axenic culture is tedious and many times unsuccessful. Axenically grown amoebae are required for a number of applications, namely, drug susceptibility testing, raising antisera or vaccine studies, development of diagnostic tests and genetic studies. The axenisation is mainly achieved from an initially xenic culture by providing an enriched nutrient medium with added antibiotics. However, the number of amoebae population in axenised medium in sometimes insufficient for performing certain studies. In this study, we have tested various formulations and additions in conventional media to find the best media, for axenic cultivation.


ACANTHAMOEBA, conventional, mammalian

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Khan NA. Acanthamoeba: Biology and Pathogenesis. 1st ed. Great Britain: Caister Academic Press; 2009.

Khurana S, Biswal M, Kaur H, Malhotra P, Arora P, Megha K, et al. Free living amoebae in water sources of critical units in a tertiary care hospital in India. Indian J Med Microbiol 2015;33:343‑8.

Visvesvara GS, Moura H, Schuster FL. Pathogenic and opportunistic free‑living amoebae: Acanthamoeba spp. Balamuthia mandrillaris,

Naegleria fowleri, and Sappinia diploidea. FEMS Immunol Med Microbiol 2007;50:1‑26.

Diamond LS. Techniques of axenic cultivation of Entamoeba histolytica Schaudinn, 1903 and E. histolytica‑like amebae. J Parasitol 1968;54:1047‑56.

Manikandan P, Bhaskar M, Revathy R, John RK, Narendran V,Panneerselvam K, et al. Acanthamoeba keratitis – A six year epidemiological review from a tertiary care eye hospital in South India.

Indian J Med Microbiol 2004;22:226‑30.

Schuster FL. Cultivation of pathogenic and opportunistic free‑living amebas. Clin Microbiol Rev 2002;15:342‑54.

Megha K, Gupta A, Sehgal R, Khurana S. An improvised medium for axenic cultivation of Acanthamoeba spp. Indian JMed Microbiol 2017;35:597-9.


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