Yeast Extract Promotes Cell Growth and Induces Production of Polyvinyl Alcohol-Degrading Enzymes

Table 3

Role of amino acids on DCW and PVAases.

Nitrogen source	DCW (g/L)	PVAases activity (U/mL)	Specific PVAases activity (kU/g)
Yeast extract	1.38 ± 0.03	1.97 ± 0.05	1.43 ± 0.04
AA mixture^a	1.25 ± 0.02	1.70 ± 0.04	1.36 ± 0.03
AA mixture (Ala^-)^b	1.24 ± 0.04	1.62 ± 0.06	1.31 ± 0.03
AA mixture (Val^-)^b	1.23 ± 0.04	1.64 ± 0.05	1.33 ± 0.04
AA mixture (Leu^-)^b	1.24 ± 0.02	1.69 ± 0.04	1.36 ± 0.05
AA mixture (Ile^-)^b	1.26 ± 0.04	1.66 ± 0.04	1.32 ± 0.03
AA mixture (Phe^-)^b	1.25 ± 0.02	1.64 ± 0.05	1.31 ± 0.03
AA mixture (Met^-)^b	1.25 ± 0.04	1.72 ± 0.06	1.38 ± 0.04
AA mixture (Pro^-)^b	1.24 ± 0.03	1.70 ± 0.04	1.37 ± 0.04
AA mixture (Gly^-)^b	1.20 ± 0.04	0.35 ± 0.01	0.29 ± 0.01
AA mixture (Ser^-)^b	1.21 ± 0.02	0.28 ± 0.01	0.23 ± 0.01
AA mixture (Thr^-)^b	1.21 ± 0.03	1.62 ± 0.04	1.34 ± 0.04
AA mixture (Cys^-)^b	1.22 ± 0.04	1.63 ± 0.05	1.34 ± 0.04
AA mixture (Tyr^-)^b	1.23 ± 0.02	0.55 ± 0.04	0.45 ± 0.02
AA mixture (His^-)^b	1.25 ± 0.03	1.68 ± 0.04	1.34 ± 0.03
AA mixture (Lys^-)^b	1.24 ± 0.03	1.64 ± 0.05	1.32 ± 0.04
AA mixture (Arg^-)^b	1.26 ± 0.02	1.67 ± 0.04	1.33 ± 0.03
AA mixture (Asp^-)^b	1.23 ± 0.04	1.67 ± 0.05	1.36 ± 0.04
AA mixture (Glu^-)^b	1.21 ± 0.03	1.61 ± 0.04	1.33 ± 0.04

^aAA mixture: amino acids mixture contains 17 amino acids, which were detected in yeast extract, respectively, Alanine (Ala), Valine (Val), Leucine (Leu), Isoleucine (Ile), Phenylalanine (Phe), Methionine (Met), Proline (Pro), Glycine (Gly), Serine (Ser), Threonine (Thr), Cysteine (Cys), Tyrosine (Tyr), Histidine (His), Lysine (Lys), Argnine (Arg), Aspartic (Asp), and Glutamic (Glu).
^bfree of which.