Table 2.

Effect of elevated CO₂ concentration (800 µmol mol⁻¹ for 24 d) on amino acids concentration in tea leaves.

Amino acids (mg g−1 DW)	Ambient CO2	Elevated CO2
Aspartic acid (Asp)	1.124 ± 0.013 b	1.730 ± 0.029 a
Threonine(Thr)	0.672 ± 0.005 a	0.448 ± 0.007 b
Serine(Ser)	0.593 ± 0.006 a	0.467 ± 0.007 b
Glutamic acid(Glu)	1.394 ± 0.021 a	1.812 ± 0.017 a
L-Theanine (Thea)	14.336 ± 0.571 b	22.624 ± 0.685 a
Proline (Pro)	0.535 ± 0.011 b	0.827 ± 0.009 a
Glycine(Gly)	0.224 ± 0.008 a	0.218 ± 0.005 a
Alanine(Ala)	0.448 ± 0.015 b	0.677 ± 0.022 a
Valine (Val)	0.856 ± 0.014 a	0.861 ± 0.009 a
Isoleucine (Ile)	0.433 ± 0.008 a	0.427 ± 0.014 a
Tyrosine (Tyr)	0.841 ± 0.031 a	0.863 ± 0.024 a
Phenylalanine(Phe)	0.540 ± 0.011 b	0.618 ± 0.019 a
Histidine (His)	0.224 ± 0.004 a	0.228 ± 0.006 a
Lysine (Lys)	0.448 ± 0.010 a	0.453 ± 0.014 a
Arginine (Arg)	0.672 ± 0.013 a	0.683 ± 0.009 a

Mean denoted by different letters indicate significant differences between the treatments (P < 0.05). DW, Dry weight.