Bioreactors & Downstream Processing | Biotechnology: Principles and Processes | Class 12 Biology

Hello everyone, this is Taneja Gupta and let's move on to the next topic recombinant DNA technology That is what We will talk about three steps. The first step is the insertion of recombinant DNA. or you can say recombinant and the second next step is what obtaining the gene product and the last one is downstream processing See, I've already told you recombinant DNA technology completed in six steps I have already discussed the first three steps. and the last three steps I will discuss in this video So let's go through them one by one. First, we take this step. insertion of recombinant DNA See, I've already told you that DNA is isolated and fused with vector So what do we have a recombinant means we have a recombinant plasmid or you can say vector Now what do we have to do? We have to take this DNA. and enter it in the host cell such a host cell which does not have a plasmid select the plasmid-free host cell and insert this plasmid in it I have already told you that host cell easily Does not accept any product or any DNA So the host cell needs to be competent. means it should be made in such a way that host cell can easily Accept it How can we develop competence? we can treat it with bivalent cation or with chilling treatment apart from it We can also opt for micro-injection. as well as we can go for the biolistic gun I have already discussed through which we insert it in the host as soon as any recombinant is inserted into it we call it transformed cell now which Is there any resistance activity? ampicillin Tetracycline won't be there As I have already told you foreign DNA has entered So it is inactive. now only ampicillin Is there any resistance activity? based on this transformed and non-transformed cells What can we do we can differentiate because non-transformed cells will not grow in the presence of ampicillin and the transformed cell will grow in the presence of ampicillin after that from this transformed cell we can isolate recombinant as well as non-recombinant we can isolate both of them recombinant plasmid-transformed cell Actually, we need this combination. recombinant transformed cell we need non-recombinant transformed cell We can distinguish between the two. I have already told you about this in my previous video I will share the link in the description box You can go through that one. so you can understand it very well I am not going to discuss this detail. so overall What is being done in this step? recombinant is being entered into host cell after entering the host cell What will it do? It will increase its number. along with the host cell as it increases its number Its product will also start What will happen? the specific product of DNA which we have to cultivate on a large scale We need it. second step obtaining gene product We are obtaining the gene product. from DNA, but we have to Scale it up to a large scale. to scale it up host cell must be grown on a large scale large scale It has to be grown on a large scale. to make it grow We take a container. which is a very large size we call it bioreactor or we call it fermentor What do we call it? bioreactor and fermenter in the second step we are talking about bioreactor How does this bioreactor work? in this bioreactor There are some main parts. First of all in bioreactor There is a culture medium. culture medium What does it do? It provides nutrition. to host cell what it provides nutrition vitamins many hormones so that This cell can grow. Overall, you could say whatever the need of the host cell the second part is inoculum What is inoculum? We take culture medium We have to put the host cell. so that the host cell can grow so the small amount small amount of this host cell host cell is called inoculum for example curd formation We do curd formation at home We take a small amount of curd. and put it in milk in the morning a small amount of curd We call it inoculum. in which some living bacteria grow later and convert whole milk in yogurt so here as well We call it inoculum. The third thing is stirrer in the bioreactor diagram stirrer It moves. because of which It provides nutrients. nutrients to host cell if it moves entire culture medium will be homogenized not just one side It provides nutrients. by keeping the homogenized mixture Nutrients will be readily available. as well as oxygen oxygen will be properly available apart from this form breaker due to agitation formation begins Formation creates a problem in bacterial cell growth So this is the form breaker. flat plate-like structure which reduces the form This is the steam inlet which is for sterilization so that no other microorganism can grow there This is the pH control. through which pH as well as temperature is controlled cultural growth is added and it is agitated so that Culture can grow in a universal and homogenized form Fine So here it grows like this now on a large scale There are two types of growth. Let's see what those are. See these bioreactors are of two types of culture medium One is the batch culture. and another is the continuous culture OK batch and continuous two types of bioreactors in batch in one go culture medium with that inoculum is added in a bioreactor and let it grow until all the nutrients are utilized and the cells reach their maximum number as soon as it reaches It is taken out and the gene product is isolated this entire bioreactor is emptied and a new culture medium and inoculum is added It is prepared. fresh It will work in one batch. Then it is taken out. This is the batch culture. whereas continuous culture What is it? that process is continuous going on What is continuous culture? See What is it? this bioreactor has an inlet and an outlet through this inlet continuous culture medium and with that inoculum both of them provide fresh This entire culture is growing and with that this used medium is taken out which is such a medium which has no nutrients left The medium that was used is removed. as well as this living cell which we also refer to culture cell OK The main thing is This medium has been removed. and the culture cell grows so it gets a fresh medium every time so it never reaches a saturation point that after this it cannot grow It is continuously growing. and continuously producing new cells which means the cells under this condition are always in log phase or we call it the exponential phase OK If I want to tell you in a simple way summarized form There are three phases in cells This is called the lag phase. This is the log phase. and this is the stationary phase Which one is it? This is the stationary phase. OK in the lag phase The cells are fresh. and there is a lot of division in the stationary phase It is heading toward decline. towards death and in the lag phase The division is just starting. so in the log phase We obtain the greatest amount of gene product. so this is why in the continuous culture We get a lot of yield. We obtain a large amount of gene product. Therefore, we prefer continuous culture. So I hope this will be clear to you What is batch culture? And what is continuous culture? OK Now we have a cell. which has grown on a large scale and it has produced a product on a large scale and all the product is inside this bioreactor inside this bioreactor There are all the cells. and also the product which means There are a lot of cells. inside this bioreactor So now we take the third step. that is the downstream processing What is this actually? It is the processing. of product isolation OK What is done here? the culture cells OK these culture cells are very agitated so that these cells can burst And what happens with this? The product is released. OK It is greatly agitated. The cells are taken. It is agitated. and the product is removed as soon as the product is there It is isolated once again. and purified OK so that no other contamination is present as soon as it is purified Now what do we do here? We mix the preservative. What do we mix? We mix the preservative so that it can extend its shelf life so that it may survive for a long time so after mixing the preservative What is done at last? Packaging is done. It is packed. after packaging What is the next step? The product is packed. It is brought to the market. but no before bringing the product to the market What is being done? It has been tested. testing means The quality is checked. whether the quality of the product is not reaching that level It has been properly tested. and if there is any error then it is corrected and if it is fully satisfied then it is brought to the market and it is sold in the market Understood. Let me tell you again in a summarized form What happened? We have a cultured cell. We have a product inside the cell. Now we will break down the cell. and remove the product we will isolate and purify Then we will mix the preservative. and extend the product's shelf life Then, finally, we will do the packaging. and before going to the market We will carry out the testing. that means from the production to the market from the product to the market that all comes under the downstream processing Understood. I hope these three steps It will be clear to you and if you will watch the previous videos then the complete recombinant DNA technology It will be clear to all of you if you still have any doubt Please enter your query in the comment box. And thank you so much, guys, for watching this video.