title: Pretreatment of coconut mill effluent using celite-immobilized hydrolytic enzyme preparation from Staphylococcus pasteuri and its impact on anaerobic digestion.
abstract: Biological treatment of oil and grease (O&G)-containing industrial effluents has long been a challenging issue. Practically feasible avenues to bring down their O&G load and enhance treatability are desired. In one such endeavour, the partially purified lipase from Staphylococcus pasteuri COM-4A was immobilized on celite carrier and applied for the enzymatic hydrolysis of unsterilized coconut oil mill effluent. In batch hydrolysis experiments, optimum conditions of 1% (w/v) immobilized lipase beads, one in four effluent dilution, and a contact time of 30 h resulted in 46% and 24% increase in volatile fatty acids and long-chain fatty acids and a concomitant 52% and 32% decrease in O&G and chemical oxygen demand (COD) levels, respectively. Batch anaerobic biodegradation trials with this prehydrolyzed effluent showed 89%, 91%, and 90% decrease in COD, proteins, and reducing sugars, respectively. These results were validated in a hybrid stirred tank--upflow anaerobic sludge blanket reactor. Average COD and O&G reductions effected by the hybrid reactor were found to be 89% and 88%, whereas that by the control reactor without enzymatic hydrolysis were only 60% and 47%, respectively. A maximum of 0.86 L methane gas was generated by the hybrid reactor per gram of VS added. Hence, this celite-immobilized crude lipase, sourced from a native laboratory isolate, seems to be a workable alternative to commercial enzyme preparations for the management of lipid-rich industrial effluents.
authors.affiliation: Dept. of Biotechnology, Kumaraguru College of Technology, Coimbatore, 641049, Tamilnadu, India.
authors.forename: Palanisamy
authors.initials: P
authors.lastname: Kanmani
authors.affiliation: Dept. of Biotechnology, Kumaraguru College of Technology, Coimbatore, 641049, Tamilnadu, India.
authors.forename: Kuppamuthu
authors.initials: K
authors.lastname: Kumaresan
authors.affiliation: Dept. of Biotechnology, Kumaraguru College of Technology, Coimbatore, 641049, Tamilnadu, India.
authors.forename: Jeyaseelan
authors.initials: J
authors.lastname: Aravind
mesh_terms: D000693:Anaerobiosis; D001673:Biodegradation, Environmental; D019149:Bioreactors; D003059:Cocos / Q000737:chemistry*; D007692:Diatomaceous Earth / Q000737:chemistry*; D004800:Enzymes, Immobilized / Q000378:metabolism*; D005232:Fatty Acids, Volatile / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D008049:Lipase / Q000378:metabolism; D008697:Methane / Q000378:metabolism; D012722:Sewage / Q000382:microbiology; D013210:Staphylococcus / Q000201:enzymology*; D013696:Temperature; D014865:Waste Disposal, Fluid
chemical_list: D004800:Enzymes, Immobilized; D005232:Fatty Acids, Volatile; D012722:Sewage; D007692:Diatomaceous Earth; D008049:Lipase; D008697:Methane
keywords: UASB reactor; chemical oxygen demand; methane generation; oil and grease