Synthesis and Performance Evaluation of Biodiesel from Waste Cooking Oil Using Copper Doped Zinc Oxide Nanocatalysts

Abstract

Membrane bound Borassus flabellifer peroxidase was purified bysalting-out, salting-inand DEAE -Cellulose anion exchange chromatographictechnique to apparenthomogeneity. Relativemolecularweightunderdenaturatingconditionwasaround40 kDa.The preparation had single isoenzyme as evidenced under non denaturating condition. It wasa glyco-and haemoprotein.It retained 100% activity for 120 hours at 700C. pHoptima with Benzidine, O-Dianisidine, Guaiacol and TetraMethylBenzidinewere around5.0. KineticstudiesshowedithadhigheraffinitytowardsTetraMethylBenzidinethanother threesubstrates. Gibb’s free energy changes oftheenzymeat 300C withBenzidine, o-Dianisidine,Guaiacol, andTetraMethylBenzidinewas-24,-17, -7and-50KJ/mole respectively. It obeyed Ping-Pong kinetics. The fluorescence intensities ofenzyme increased linearly as hydrogen peroxide concentration increased due to exposure ofits hydrophobic moietytotheenvironment.PeelstainingwithGuaiacolsubstantiateditas membrane bound protein. BFP was ionically interacting with stone parts of its fruit. The apparently homogeneous membrane bound peroxidase was reversibly inhibited by various aromatic alcohols and its IC50values were determined. Dixon plot clearly showed mixed type of inhibition. kivalues of peroxidase-inhibitor complexes were determined. The homogenous peroxidase had non-covalently interacting triglycerides or triglyceride esterified phytosterols. This peroxidase was interacting with acid hydrolysable low density lipoprotein but not with high density lipoprotein. This may be one of the reasonsfor its stability, catalysis in organic solvents and non consumption by human beings.Immunoprecipitation experiments (IgY) indicated that the epitope present in BFP and HRP are same. Cibacron Blue G F3A interacted with BFP.Derivitization of BFP indicated the proper positioning of lysine and tyrosine that was essential for maintaining its catalytic activity. Further studies may prove it as lipophilic enzyme. These waste stone parts may be utilized in extracting phytosterols and fatty acids which have medicinal value.