 Dear students, the experiment which we are going to perform today is regarding the extraction of hydrolytic crude enzymes from microbes. So before we start our experiment, I would like to give you a very brief introduction regarding enzymes. Enzymes are basically globular protein in nature and they are made up of amino acids. Amino acids are the building blocks of enzymes. There are different types of enzymes on different categories, paste, like the two major categories of enzymes are intracellular enzymes and extracellular enzymes. Intracellular enzymes are those enzymes which produce inside the cell, whereas the extracellular enzymes are those enzymes which produce outside the cell. So let me first introduce with the chemical apparatus which we will use in this experiment. Here we have the vegetative culture of bacterial microbes which we will use as inoculum. In this class, I have 100 ml of fermentation media. So in very first step what we will do is that we will take 1 ml of this inoculum and we will transfer it into fermentation media with the help of micropipers. Let's begin with the experiment. We are now done with the inoculation in a sterilized environment. Now we will simply put our flask into a shaking incubator at 200 rpm, 37 degree centigrade per 48 hours. So now we will put our inoculated media in shaking incubator for 48 hours at 200 rpm and 37 degree centigrade. As 48 hours has been completed, now we will take out our flask from the shaking incubator and will pour our inoculated media into different falcon of 15 ml capacity for centrifugation. Now let's move toward the next step which is centrifugation. So students, I have taken 10 ml of inoculated media in these two different falcons of 15 ml capacity for centrifugation. Now I will put these falcons in centrifugation machine. As centrifugation has been started, we will wait for the completion of centrifugation time. As the centrifugation time has been completed, now we will take out our falcons from centrifugation machine. Let's discuss the results. Here in this tube you can see at the bottom there is a white milky color pellet. As in the very beginning of experiment I have told you that there are two types of enzymes. One is extracellular and the second one is intracellular. So at the bottom you can see there is a pellet. In case of intracellular enzyme, the enzyme will be present in the pellet which is present at the bottom of this tube whereas in case of extracellular enzyme, the enzyme will be in the supernatant.