ABSTRACT
A two-layer plate was developed for in situ detection of siderophore from halophilic archaea. Halophilic archaea could grow on the upper nutrient layer without addition of iron and excrete siderophore under iron-limited stress.The lower layer was the detection agar,which contained universal blue-coloured ferric-CAS complex.The presence of the siderophore was indicated by the decolorization of the blue complex, resulting in a yellow-orange halo around colonies growing on the upper nutrient layer,when the excreted siderophore penetrated from the upper nutrient layer into the lower detection agar.The results showed that the two-layer plate method was applicable to the detection of siderophore from halophilic archaea, which was more convenient and definite than former approach for halophilic archaea siderophore detection.