MORPHO-MOLECULAR IDENTIFICATION OF A NOVEL ASPERGILLUS SPP. AND ITS CULTURAL OPTIMIZATION FOR LIPASES PRODUCTION

Abstract

Different lipid rich products were used to obtain oil degrading fungal isolates. The isolates were codified for referral to our culture bank and compared for their lipolytic potential. Amongst the isolates, MBL-1412 isolated from the cooked “sliced cicer arietinum” (Channa Daal) was found to be a potent hyper-producer and was optimized for lipase production under solid state fermentation. Initial systematic treatment based upon micrometric data and consultation with the standard monographs and fungus ended up with its identification as Aspergillus sp. The identification confirmed that the fungus belongs to genus Aspergillus, by DNA barcoding marker like 18S rRNA gene sequence.Later, the sequence was registered with accession no. KM924434 in the public nucleotide library (genbank) of NCBI. Fungal culture was maintained on 2% potato dextrose agar (PDA) during the study. Diverse substrates of agricultural byproducts under varied incubation temperature, time interval, inoculum level and different pH of diluent were used as parameters of optimization for hyperproduction of lipases. Different carbon and nitrogen sources as additives of culture medium were applied for enhancement of lipase production. Almond meal (10g) with inoculum level @1.5 mL after 48 h of time course at 50ºC and 6 pH were selected to be the best eco-cultural conditions for optimal lipases production by Aspergillus sp. MBL-1412. Supplementary additives of nitrogen and carbon sources to the basal substrate improved lipases production appreciably. Ammonium chloride (1%) as inorganic nitrogen source, nutrient broth (0.8%) as organic nitrogen source and starch (0.8%) as carbon source were found as best media additives for enhanced extracellular lipases yield.