Isolation of Leptospirillum ferriphilum by single-layered solid medium

Abstract

According to physiological and biochemical characteristics of Leptospirillum ferriphilum, a strain of object bacteria was isolated successfully. Bacteria were enriched by selective liquid medium and plated on designed single-layered agar solid medium. Colony was cultured and bacteria were collected. The morphologies of the object bacteria were observed using crystal violet staining, scanning electron microscope(SEM) and transmission electron microscope (TEM). The result of 16S rDNA identification shows that this bacterium belongs to Leptospirillum ferriphilum and it is named as Leptospirillum ferriphilum strain D1. These results indicate that this new single-layered agar solid medium is efficient and simple for isolation of Leptospirillum ferriphilum. Additionally, physiological-biochemical characteristics show that the optimum initial pH value and its growth temperature are 1.68 and 40 °C, respectively. The culture of it is used to leach a complex concentrate chalocpyrite, the leaching efficiencies of copper and iron are 1.93% and 13.74%, respectively, and it is more effective than the A. ferrooxidans culture in the leaching of the complex concentrate chalcopyrite.

Keywords

Leptospirillum ferriphilum / isolation / purification / solid medium / bioleaching / concentrate chalcopyrite

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