Amino add fermentation

In this chapter we consider amino acid production by fermentation and by chemo-enzymatic methods. We first consider the stereochemistry of amino adds and the importance of chirality in chemical synthesis. General approaches to amino add fermentation and recovery of amino adds from fermentation broths are then dealt with, followed by a detailed consideration of the production of L-phenylalanine by direct fermentation. Later in this chapter, chemo-enzymatic methods of amino acid... 

We can differentiate between three possible methods of amino add fermentation ... 

Batch fermentation is the most widely used method of amino add production. Here the fermentation is a dosed culture system which contains an initial, limited amount of nutrient. After the seed inoculum has been introduced the cells start to grow at the expense of the nutrients that are available. A short adaptation time is usually necessary (lag phase) before cells enter the logarithmic growth phase (exponential phase). Nutrients soon become limited and they enter the stationary phase in which growth has (almost) ceased. In amino add fermentations, production of the amino add normally starts in the early logarithmic phase and continues through the stationary phase. 

Give possible reasons for selecting each of the following operating conditions for a hypothetical amino add fermentation. 

SAQ 8.7 The product value at 100% capadty will now be (total cost of production + 7 to 15% ROD, ie 16.04 to 1654 + 1.12 to 2.48. So the minimum product value will be 17.16 per kg of L-phenylalanine and the maximum product value 19.02 per kg of L-phenylalanine. It is rattier difficult to say whether this fictitious process would survive or could compete. Actual data are absolutely necessary. On the other hand this exercise gives us a better understanding of process economics and can also be used to compare a fermentative process for the production of amino adds with, for example, a chemo-enzymatic process. Calculate the return on investment over a 15 year period for an amino add fermentation, based on the following data and assumptions. Production capadty = 500 tonnes per annum Selling price of product = 50 kg Cost price of product = 24.5 kg 1 Capital = 40 million Taxes = 50%. Assumptions Cost of dealer discount, distribution and freight = 20% total sales Startup costs = 10% of capital Working capital = 25% of net sales Administration plus R and D costs = 12.5% of net sales. 

Calculate the return on investment over a 15 year period for an amino add fermentation, based on the foUowing data and assumptions. 

Kinoshita S, Udaka S, Shimono M. (1957). Studies on the amino add fermentation. Part 1. Production of L-glutamic acid by various microorganisms. J Gen Appl Microbiol, 50, 193-205. 

Nara T, Samejkna H, Kinoshita S. (1964). Effect of penicillin on amino add fermentation. Agric Biol Chem, 28, 120-124. 

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