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Practical 4 - Amylase Activity in Germinating BarleyIntroductionMetabolism is the biochemical processes occurring within living organisms that are necessary forthe maintenance of life which is usually categorized into two, catabolism and anabolism.Catabolism is the breakdown of substances to yield energy for vital processes whereasanabolism, on the other hand, is the synthesis of substances using energy stored.Germination takes place when the energy produced by the hydrolysis of starch or lipids stored inendosperm are mobilized to provide ATP required for growth. Amylase acts as the primaryenzyme to hydrolyze starch into glucose which is used as an energy source.The aim of this experiment is to investigate and compare the amylase activity in different stagesof barley seedling development by measuring the rate of starch hydrolysis and to identify thepresence of maltose in the hydrolysis process. The amylase activity is the highest in germinatingbarley seeds followed by germinated, then lowest in dormant barley seeds.(152 words)MethodAmylase is extracted by grinding 10 barley seeds in 10mL of buffer to make a puree afterweighing. The puree is then filtered to remove unwanted debris and the volume of amylaseextract is measured. A diluted amylase extract is prepared through five-fold dilution by adding20mL of buffer into 5mL of the amylase extract. A control extract is prepared by heating 5mL ofdiluted amylase extract for 10 minutes to denature enzymes in the extract.The amylase activity is determined by testing the reaction mixture containing 1mL of 0.5% starchsolution in 5mL of buffer with iodine at constant time intervals after the addition of 1mL ofdiluted amylase extract. The procedure is repeated by replacing diluted amylase extract with1mL of boiled control extract. The colour intensity decreases as the reaction proceeds until nocolour develops indicating the achromic point where all starch is hydrolyzed.The time taken to reach the achromic point should be within 5-20 minutes. The ratio of volumeof buffer to amylase extract is increased if the achromic point is reached in less than 5 minutesand the ratio is reduced if it exceeds 20 minutes.