Table 3. Effect of medium components on the cytidine assay.
| Compound | Concentration (mM) | % absorbance | Compound | Concentration (g/L) | % absorbance | Compound | Concentration (mM) | % absorbance |
|---|---|---|---|---|---|---|---|---|
| Mineral salts | Nutritional components | Amino acids | ||||||
| NaCl | 10 | 99.1 | Wort extract | 25 | 126.9 | Aspartic acid | 2 | 2 |
| ZnCl2 | 10 | 213.2 | Tryptone | 10 | 77.3 | Cysteine | 2 | 0 |
| CoCl2 | 10 | 127.5 | Yeast extract | 5 | 85.5 | Glutamate | 2 | 61.6 |
| FeCl3 | 10 | 92.4 | Beef powder | 5 | 112 | Histidine | 2 | 0 |
| CuCl2 | 10 | 101.8 | Lactose | 10 | 86.8 | Isoleucine | 2 | 16.6 |
| CaSO4 | 10 | 91.9 | Maltose | 10 | 110.3 | Leucine | 2 | 87.7 |
| MnSO4 | 10 | 83.2 | Sucrose | 10 | 90.5 | Lysine | 2 | 23.4 |
| Na2SO4 | 10 | 85.9 | D-glucose | 10 | 102.1 | Methionine | 2 | 0 |
| FeSO4 | 10 | 109.7 | D-xylose | 10 | 98.9 | Phenylalanine | 2 | 2.23 |
| CuSO4 | 10 | 87.9 | L-arabinose | 10 | 97.4 | Tryptophan | 2 | 5.8 |
| Sodium acetate | 10 | 115.6 | D-Mannitol | 10 | 89.7 | Tyrosine | 2 | 63.5 |
| NaHCO3 | 10 | 99.1 | D-Sorbitol | 10 | 88.1 | Valine | 2 | 17.3 |
| NaNO2 | 10 | 96.4 | Urea | 10 | 96.8 | |||
| Citric acid | 10 | 81.8 | Betaine | 10 | 64.4 | |||
| Sodium citrate | 10 | 88.6 | ||||||
| Calcium carbonate | 10 | 89.9 |
Note: Values reported in the table were the average of three parallel determinations. The absorbance was reported as a percentage of that obtained with cytidine, (2 mM) dissolved in water, i.e., ((absorbance with cytidine + test compound)/absorbance with cytidine alone) × 100%. A value of 100 means no interference; a value of 0 means total interference, i.e., no color formation at all, and values greater than 100 mean the test compound enhances the absorbance of the solution.