Zinc Affects Differently Growth, Photosynthesis, Antioxidant Enzyme Activities and Phytochelatin Synthase Expression of Four Marine Diatoms

Table 1

Growth rate, maximum cell density, chlorophyll a and c contents, total Chl, Chl a/Chl c ratio in Amphora acutiuscula, Amphora coffeaeformis, Nitzschia palea, and Entomoneis paludosa grown in ASW (control) or in the presence of Zn 20 μM added to ASW.

Species	A. acutiuscula		A. coffeaeformis		N. palea		E. paludosa
	Control	Zn 20 μM	Control	Zn 20 μM	Control	Zn 20 μM	Control	Zn 20 μM
Growth rate (day^−1)	1.210 ± 0.074^a	1.281 ± 0.014^a	1.198 ± 0.192^a	0.957 ± 0.108^a	0.258 ± 0.028^a	0.405 ± 0.069^b	0.630 ± 0.430^a	0.020 ± 0.017^b
Maximum cell density (10^3 cells mL^−1)	591± 8^a	498 ± 5^b	617 ± 4^a	480 ± 4^b	1308 ± 133^a	627 ± 8^b	298 ± 14^a	48 ± 1^b
Chl a (μg 10^−6 cells)	3.22 ± 0.20^a	2.72 ± 0.20^b	1.10 ± 0.03^a	0.87 ± 0.03^b	1.03 ± 0.05^a	1.42 ± 0.01^b	2.79 ± 0.36^a	2.27 ± 0.10^a
Chl c (μg 10^−6 cells)	0.32 ±  0.01^a	0.37 ± 0.03^b	0.13 ± 0.01^a	0.11 ± 0.01^a	0.21 ± 0.02^a	0.29 ± 0.01^b	0.34 ± 0.06^a	0.37 ± 0.03^a
Total Chl (μg 10^−6 cells)	3.54 ± 0.21^a	3.09 ± 0.09^a	1.24 ± 0.04^a	0.97 ± 0.03^b	1.23 ± 0.07^a	1.71 ± 0.22^a	3.13 ± 0.42^a	2.64 ± 0.13^a
Chl a/Chl c	10.09 ± 0.40^a	7.52 ± 0.75^b	8.30 ± 0.14^a	8.07 ± 0.09^a	4.96 ± 0.12^a	4.89 ± 0.22^a	8.2 ± 0.40^a	6.13 ± 0.15^a

Meanvalues±SE (n = 3–5). Significant different data are indicated with different superscripted letters (Tukey Test, 𝑃≤0.05).