Glucose glutamic acid

Another problem is the cahbration of BOD-sensor to enable the comparison with the conventional BOD. For cahbrating a BOD-sensor, a glucose-glutamic acid standard solution (the so-called GGA-standard), which is also used as standard solution for the BODj-method [71], or aqueous solutions of glucose or glycerol with a defined BODj [43,54] are used. 

Fig. 110. Measuring curves of BOD sensors containing different microorganisms. Glucose-glutamic acid (GGA) standard solutions were used as BOD reference.

A glucose-glutamic acid solution (150 ppm glucose and 150 ppm glutamate GGA solution) equivalent to a BOD5 value of 220 ppm was prepared for calibration of BOD values. BOD standard solution (5 pL) which was treated with pure oxygen gas was dropped onto the hole of the chip. After 20 min bioluminescence from the well was measured. 

Response curves of Bacillus subtilis- and THchosporon cutaneum-based sensors to glucose-glutamic acid standard solution containing 22 mg/L biochemical oxygen demand (BOD). Reproduced from (420] with permission from Springer-Verlag. 

The extracellular accumulation of peptides containing glutamic acid which occurs when Staph, aureus is incubated with glucose, glutamic acid, and either cysteine or alanine is not easily followed on an accurate quantitative basis. The action of chloramphenicol and aureomycin on the formation of these peptides has been studied and, although no clear-cut results have been obtained, it is certain that the formation is not as sensitive as protein formation is to these antibiotics. Chloramphenicol at 100 Mg./ml. is without significant effect on the formation of these peptides, while aureomycin produces a significant inhibition at 100 Mg-/ml. but not at 1 ng./ml. 

Grown on glucose, glutamic acid medium fatty acid composition affected by medium Authors cited give fatty acid composition on other media. 

In Cosmetics. Amino acids and their derivatives occur in skin protein, and they exhibit a controlling or buffering effect of pH variation in skin and a bactericidal effect (216). Serine is one component of skin care cream or lotion. Ai-Acylglutamic acid triethanolamine monosalt is used for shampoo. Glucose glutamate is a moisturizing compound for hair and skin (234). 

Freeze-drying is a relatively gentle way of removing water from proteins in solution. However, this process can promote the inactivation of some protein types, and specific excipients (cryopro-tectants) are usually added to the product in order to minimize such inactivation. Commonly used cryoprotectants include carbohydrates (such as glucose and sucrose), proteins (such as HSA), and amino acids (such as lysine, arginine or glutamic acid). Alcohols/polyols have also found some application as cryoprotectants. 

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