Screening and identification of thermophilic microorganisms that produce extracellular lipase from Hulu Langat Hot Spring / Ummul Hanan Mohamad

Lipolytic thermophilic bacteria was successfully isolated from Hulu Langat hot spring water. Molecular biological technique based on 16SRNA analysis revealed that the isolated bacteria species was Bacillus subtilis. Selective isolation of bacteria from hotspring water is performed using Rhodamine-B Tween 80 agar in which lipase producer is identified based on presence of orange fluorescence halos around colonies when plate is irradiated with UV light. Further characterisation of isolated bacteria is performed based on the colony characteristics on media as well as Gram staining. Bacillus subtilis isolated from hotspring appeared as clear looking colony with reddish tint. It was irregular in shaped, flat, mucoid and big. It was also motile and catalase positive. Under Gram staining, it was arranged in chains and was big long rods. The isolated lipase producer grew best at 55°C at alkaline pH of 8.1.