Table 3.
Micro- and macroelement concentrations in algal extract samples.
| Trace Element, d.m. | Algal Extract Samples | |||||
|---|---|---|---|---|---|---|
| Macroalgae | Microalgae | |||||
| Cla | Furc | Ul | Chlo | Sp1 | Sp2 | |
| Macroelements, g kg−1 d.m. | ||||||
| Na | 220 ± 13 a,C | 277 ± 11 b,D | 517 ± 25 c,F | 27.1 ± 1.3 a,A | 136 ± 6 b,B | 458 ± 18 c,E |
| Mg | 140 ± 9 a,D | 206 ± 14 b,E | 259 ± 14 c,F | 11.7 ± 0.9 a,A | 15.5 ± 1.1 b,B | 51.0 ± 3.2 c,C |
| K | 975 ± 32 c,E | 445 ± 21 b,D | 336 ± 19 a,C | 77 ± 4 a,A | 110 ± 5 b,B | 950 ± 29 c,E |
| Ca | 40.2 ± 3.1 b,E | 68.3 ± 4.2 c,F | 18.8 ± 0.7 a,C | 2.36 ± 0.14 a,A | 7.17 ± 0.16 b,B | 29.1 ± 1.7 c,D |
| Essential microelements, d.m. | ||||||
| Cr, mg kg−1 | 0.003 ± 0.001 a,A | 0.042 ± 0.003 c,C | 0.023 ± 0.002 b,B | 0.002 ± 0.001 a,A | 0.005 ± 0.002 a,A | 0.056 ± 0.004 b,D |
| Mn, g kg−1 | 7.41 ± 0.52 c,F | 1.10 ± 0.07 b,E | 0.435 ± 0.021 a,D | 0.028 ± 0.002 a,A | 0.063 ± 0.004 b,B | 0.333 ± 0.021 c,C |
| Fe, g kg−1 | 4.34 ± 0.31 c,E | 2.66 ± 0.19 b,D | 1.09 ± 0.08 a,A | 2.25 ± 0.011 b,C | 1.37 ± 0.009 a,B | 4.73 ± 0.15 c,E |
| Co, mg kg−1 | 0.064 ± 0.005 d,D | 0.003 ± 0.001 a,A | 0.006 ± 0.001 b,B | 0.002 ± 0.001 a,A | 0.002 ± 0.001 a,A | 0.040 ± 0.003 c,C |
| Ni, mg kg−1 | 0.301 ± 0.011 c,D | 0.015 ± 0.002 b,B | 0.005 ± 0.001 a,A | nd | nd | 0.020 ± 0.001 C |
| Cu, mg kg−1 | 0.101 ± 0.009 b,D | 0.004 ± 0.001 a,A | 0.202 ± 0.013 c,E | 0.077 ± 0.003 b,C | 0.020 ± 0.002 a,B | 0.071 ± 0.005 b,C |
| Se, mg kg−1 | 0.004 ± 0.002 a,A | 0.001 ± 0.001 a,A | 0.002 ± 0.001 a,A | nd | nd | 0.004 ± 0.002 A |
| Non-essential microelements, d.m. | ||||||
| As, mg kg−1 | 0.334 ± 0.021 b,D | 0.255 ± 0.016 a,C | 0.437 ± 0.031 c,E | 0.004 ± 0.002 a,A | 0.002 ± 0.001 a,A | 0.022 ± 0.002 b,B |
| V, mg kg−1 | 0.006 ± 0.001 a,B | 0.004 ± 0.001 a,A,B | 0.004 ± 0.001 a,A,B | 0.001 ± 0.001 a,A | nd | 0.002 ± 0.001 a,A |
| Rb, mg kg−1 | 0.507 ± 0.026 c,F | 0.252 ± 0.017 b,E | 0.140 ± 0.009 a,C | 0.020 ± 0.001 b,B | 0.010 ± 0.001 a,A | 0.181 ± 0.012 c,D |
| Sr, mg kg−1 | 0.398 ± 0.014 b,E | 0.621 ± 0.035 c,F | 0.245 ± 0.011 a,C | 0.017 ± 0.002 a,A | 0.060 ± 0.003 b,B | 0.346 ± 0.019 c,D |
| Mo, mg kg−1 | nd | 0.004 ± 0.001 a,A | 0.007 ± 0.001 b,B | nd | 0.004 ± 0.001 a,A | 0.010 ± 0.001 b,C |
| Ag, mg kg−1 | 0.018 ± 0.001 a,A | 0.098 ± 0.007 c,C | 0.029 ± 0.002 b,B | nd | 0.034 ± 0.003 a,B | 0.164 ± 0.013 b,D |
| Sb, mg kg−1 | 0.046 ± 0.003 b,C | 0.005 ± 0.001 a,A | 0.163 ± 0.007 c,E | nd | 0.032 ± 0.003 a,B | 0.098 ± 0.008 b,D |
| Cs, mg kg−1 | nd | 0.001 ± 0.000 | nd | nd | nd | nd |
| Ti, mg kg−1 | nd | nd | nd | nd | nd | 0.001 ± 0.000 |
| Cd, mg kg−1 | nd | nd | nd | nd | nd | 0.001 ± 0.000 |
| Ba, mg kg−1 | 0.032 ± 0.002 b,C | 0.033 ± 0.002 b,C | 0.008 ± 0.001 a,B | 0.001 ± 0.000 a,A | 0.006 ± 0.001 b,B | 0.043 ± 0.003 c,D |
| Pb, mg kg−1 | 0.002 ± 0.001 a,A | 0.003 ± 0.001 a,b,A,B | 0.001 ± 0.000 a,A | 0.001 ± 0.000 a,A | 0.001 ± 0.000 a,A | 0.002 ± 0.001 a,A |
| Al, g kg−1 | 0.343 ± 0.018 b,B | 1.14 ± 0.01 c,C | 0.111 ± 0.009 a,A | nd | nd | 1.15 ± 0.009 C |
| Li, mg kg−1 | 0.013 ± 0.002 a,B | 0.023 ± 0.002 b,C | 0.047 ± 0.003 c,D | 0.002 ± 0.001 a,A | 0.005 ± 0.002 a,A | 0.070 ± 0.006 b,E |
Cla, Cladophora rupestris; Ul, Ulva intestinalis; Furc, Furcellaria lumbricalis; Chlo, Chlorella vulgaris; Sp1, Spirulina (Arthrospira platensis) obtained from the University of Texas; Sp2, Spirulina (Ltd. “Spila“). Data are represented as means (n = 3, replicates of analysis) ± SD. a–c for the same analytical parameters, in macro- and microalgae groups, means with different letters are significantly different (p ≤ 0.05). A–F for the same analytical parameters, in all algal samples, means with different letters are significantly different (p ≤ 0.05); nd - not determined.