Indian Journal of Biotechnology Vol. 4, April 2005, pp. 293-294 Extracellular lipases from anaerobic microorganisms of Antarctic Pramod W Ramteke*, Babu Joseph and M Kuddus Department of Biotechnology, Allahabad Agricultural Institute – Deemed University, Allahabad 211 007, India Received 24 March 2004; revised 9 June 2004; accepted 25 June 2004 Anaerobic microorganisms of Antarctic were investigated for production of extracellular lipases. Of 137 anaerobic strains studied, 49 (35.7%) strains showed lipolytic activity. Amongst the strains studied, 64 were psychrophiles (29 strict, 35 facultative) and 73 psychrotrophs (31 strict, 42 facultative). Of lipase producing psychrophiles, 9 (31.0%) were strict and 11 (31.4%) facultative anaerobes, whereas amongst lipase producing psychrotrophs, 13 (41.9%) were strict and 16 (38.0%) facultative anaerobes. Keywords: Antarctica, anaerobe, lipase IPC Code: Int. Cl. 7 A01N63/02; C12N9/16, 9/20 Lipases (triacylglecerol acylhydrolases, EC: 3:1.1.3) are hydrolases acting on the carboxyl ester bonds present in acylglycerols to liberate organic acids and glycerol. Many microorganisms such as bacteria, yeast and fungi are known to secrete lipases during growth on hydrophobic substrates. Lipases have generated considerable interest due to their industrial applications in detergent industries, flavour development in food processing industries, processing of fats and oils, application in organic synthesis, production of optically active compounds, polymer synthesis, and intramolecular esterification 1,2 . Numerous organisms, particularly bacteria, yeast, unicellular algae and fungi have been found successfully colonizing cold environments, the most abundant environment on the surface of our planet 3 . Despite extremely harsh climatic conditions, Antarctica continent is also enriched and dominated by a variety of microorganisms 4-6 , which could be potential source of cold adapted enzymes. When a target enzyme type, one with commercial potential, has been established, extensive screening of bacterial isolates can be initiated. Examples may include lipases and proteases as they have the broadest applicability 7 . Lipases produced by psychrophilic Antarctic bacteria have been investigated 8,9 . The Indian effort to understand the Antarctic microbiology is limited to isolation and characterization of the microbes from the maritime Antarctic water, soil and sediments from the area of old Indian station “Dakshin Gangotri” 10,11 . However, to the best of our knowledge, lipases isolated from Antarctica anaerobes are not reported in India. Therefore, anaerobes obtained from Antarctica were screened for extracellular lipase production. Thirty-two soil samples were collected from the vicinity of Indian station “Maitri” of the Schirmacher Oasis (Queen Maud Land/Dakshin Gangotri hill ranges), 70 km away from Princess Astrid coast of Antarctica between the inland and shelf ice occupying an area of 35 Km 2 , situated between the geographical coordinates 70º45'12" to 70º46'30" S latitude and 11º22'44" to 11º54'00" E longitude. During the sampling period (January to February 1999), the average soil temperature was in the range of –3 to 3ºC. Most of the soil samples were collected under the mat of mosses and edges of lakes. For collection of soil samples, about 22-30 cm of surface soil was cleared with sterile spatula, and the underlying soil was collected and transferred to sterile sealed polythene bags. Viable anaerobes were obtained by following standard microbiological methods using anaerobic agar (BBL, India) media (pH 7.0 ± 0.2). All the soil samples were plated in triplicate after appropriate dilutions to determine anaerobic population both at room temperature 26±2ºC as well as at freezing temperature (4ºC) and were incubated in anaerobic jars (E. Merck). Lipase activity was detected by Tween 80-agar method 12 . Nutrient agar medium (BBL India) was supplemented with CaCl 2 .2H 2 O, 0.01%. Tween 80, sterilized for 20 min at 120ºC was added to the molten agar medium at 45ºC to give a final concentration of 1%. The medium was shaken until the Tween 80 had dissolved completely and then the isolates were streaked on to the petriplates. The plates were incubated at 4ºC for 3-7 days under anaerobic condition. An opaque halo zone occurring around the colonies indicated the positive test. __________________ *Author for correspondence: Tel: 91-532-2684296. Fax: 91-532-2684593/2684394 E-mail: pwramteke@yahoo.com