 In this module we will just link our recover and purification steps with our missing item in our previous modules, because as I told you in a recovering process sometimes we have to crystallize our product before drawing. So sometimes when we crystallize that based upon different chemical nature, so then you can say that the crystallization is the established methods used in the initial recovery of the organic acids and the amino acids and more widely used for the final purification of diverse range of products. As an example of the citric acid, when we produce the citric acid during the fermentation process the filter broth is treated with calcium hydroxide. So that the relatively insoluble calcium crystals will be precipitated from the solution. So the concept of recovering the metabolite directly from an unfiltered fermentation broth is of considerable interest because of its simplicity. So that when we use this crystallization process that actually reduce the purification and recovery and purification steps, so ultimately when we reduce the recovery and purification step that automatically effect our product cost. So as concerned the concept of recovering the metabolite directly from an unfiltered fermentation broth is of considerable interest because of its due to simplicity. The reduction in the process stage and the potential of the cost saving as I have already told you. So as concerned the Rofler et al in 1984 the use of number of techniques for the institute recovery of the fermentation product as compared to the crystallization. So the first is the vacuum and the flash fermentation for the recovery of ethanol from the fermentation broth. So that is another approach. The third is the extractive fermentation liquid, liquid and phase aqueous from the recovery of organic acids and the toxin produced by clostridium techni like process organisms. So as concerned then is the adsorption for the recovery of ethanol and cyclohexamide these depending upon the nature of the different products. So as concerned the ion exchange and chromatographic technique. So the ion exchange in the extraction of the salicylic acid and the antibiotics is mostly used. So the other method is when we use we have to remove some salt from our product then the dialysis is the possible techniques. So the dialysis of the fermentation in the selective recovery of the lactic acids, salicylic acid and cyclohexene like products. So these are the different possible other measures which we can apply during the purification steps of different products as you have seen in this module.