Effect of Light Intensity and Quality on Growth Rate and Composition of Chlorella vulgaris
Abstract
:1. Introduction
2. Materials and Methods
2.1. Microalga Cultivation
2.1.1. Cultivation of C. vulgaris in the Greenhouse Environment
2.1.2. Cultivation of C. vulgaris in a Closed Laboratory Bioreactor
2.1.3. Culture Medium
2.2. Measurements
2.3. Nutrient Composition Analyses
2.4. Algal Growth Kinetic Model as a Function of Light Intensity
2.5. Statistical Analysis
3. Results
3.1. Growth Rate of C. vulgaris in the Greenhouse
3.2. Composition of C. vulgaris in the Greenhouse
3.3. Growth rate of C. vulgaris in the Closed Bioreactor
3.4. Composition of C. vulgaris in the Closed Bioreactor
3.5. Algal Growth Kinetic Model as a Function of Light Intensity
4. Discussion
4.1. Effect of Light Intensity on the Growth Rate of C. vulgaris
4.2. Effect of Light Intensity on Composition of C. vulgaris
4.2.1. Experiments in the Greenhouse
4.2.2. Experiments in the Closed Bioreactor—Effect of Wavelength and Artificial Irradiation
5. Conclusions
Author Contributions
Funding
Conflicts of Interest
References
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Growth Rate (in d−1) and Productivity (in g L−1 d−1) | Solar Irradiance | ||
---|---|---|---|
100% | 50% | 25% | |
June | |||
μexp | 0.329 ± 0.030 a | 0.252 ± 0.022 b | 0.181 ± 0.020 c |
Pb | 0.022 ± 0.001 a | 0.015 ± 0.002 b | 0.011 ± 0.000 c |
Pl | 0.006 ± 0.000 a | 0.003 ± 0.000 b | 0.002 ± 0.000 c |
Pp | 0.005 ± 0.000 a | 0.004 ± 0.000 b | 0.003 ± 0.000 c |
September | |||
μexp | 0.293 ± 0.033 a | 0.221 ± 0.022 b | 0.169 ± 0.020 c |
Pb | 0.018 ± 0.001 a | 0.014 ± 0.001 b | 0.010 ± 0.001 c |
Pl | 0.004 ± 0.000 a | 0.003 ± 0.000 b | 0.002 ± 0.000 c |
Pp | 0.005 ± 0.000 a | 0.004 ± 0.000 b | 0.003 ± 0.000 c |
Solar Irradiance | Moisture | Lipids | Proteins | Ash | Fiber | NFE |
---|---|---|---|---|---|---|
June | ||||||
100% | 7.925 ± 0.263 a | 25.567 ± 0.301 a | 23.735 ± 0.371 a | 12.275 ± 0.411 a | 9.425 ± 0.275 a | 21.073 ± 0.483 c |
50% | 7.950 ± 0.311 a | 22.279 ± 0.157 b | 23.606 ± 0.817 a | 12.375 ± 0.299 a | 9.325 ± 0.189 a | 24.466 ± 0.990 b |
25% | 8.050 ± 0.191 a | 19.456 ± 0.342 c | 23.801 ± 0.651 a | 12.275 ± 0.359 a | 9.225 ± 0.320 a | 27.193 ± 0.730 a |
September | ||||||
100% | 7.725 ± 0.171 a | 24.716 ± 0.200 a | 27.634 ± 0.520 a | 12.125 ± 0.330 a | 9.250 ± 0.208 a | 18.550 ± 0.488 c |
50% | 7.975 ± 0.171 a | 21.300 ± 0.269 b | 27.563 ± 0.878 a | 12.338 ± 0.229 a | 9.300 ± 0.365 a | 21.524 ± 1.200 b |
25% | 8.000 ± 0.082 a | 17.292 ± 0.267 c | 27.121 ± 0.794 a | 12.275 ± 0.386 a | 9.475 ± 0.206 a | 25.837 ± 0.681 a |
Growth Rate (in d−1) and Productivity (in g L−1 d−1) | I420–520/I580–680 | |||
---|---|---|---|---|
1.30 | 0.90 | 0.60 | 0.30 | |
μexp | 0.394 ± 0.021 a | 0.346 ± 0.022 b | 0.266 ± 0.031 c | 0.183 ± 0.023 d |
Pb | 0.080 ± 0.004 a | 0.060 ± 0.001 b | 0.041 ± 0.002 c | 0.030 ± 0.002 d |
Pl | 0.010 ± 0.000 a | 0.009 ± 0.000 a | 0.008 ± 0.000 b | 0.006 ± 0.000 c |
Pp | 0.021 ± 0.000 a | 0.015 ± 0.000 b | 0.010 ± 0.000 c | 0.008 ± 0.000 d |
Light Intensity (μmol Photons m−2 s−1) | ||||
520 | 390 | 260 | 130 | |
μexp | 0.363 ± 0.023 a | 0.318 ± 0.020 b | 0.276 ± 0.011 c | 0.166 ± 0.020 d |
Pb | 0.085 ± 0.001 a | 0.054 ± 0.001 b | 0.041 ± 0.001 c | 0.032 ± 0.003 d |
Pl | 0.019 ± 0.000 a | 0.008 ± 0.000 b | 0.004 ± 0.000 c | 0.003 ± 0.000 d |
Pp | 0.022 ± 0.000 a | 0.014 ± 0.000 b | 0.010 ± 0.000 c | 0.008 ± 0.000 d |
I420–520/I580–680 | Moisture | Lipids | Proteins | Ash | Fiber | NFE |
---|---|---|---|---|---|---|
1.30 | 8.067 ± 0.252 a | 12.680 ± 0.191 d | 26.710 ± 0.274 a | 12.367 ± 0.451 a | 9.267 ± 0.252 a | 30.910 ± 0.476 a |
0.90 | 7.800 ± 0.100 a | 16.219 ± 0.655 c | 25.509 ± 0.141 b | 12.267 ± 0.252 a | 9.467 ± 0.250 a | 28.738 ± 0.725 b |
0.60 | 7.867 ± 0.351 a | 18.447 ± 0.436 b | 25.249 ± 0.304 b | 12.333 ± 0.473 a | 9.333 ± 0.255 a | 26.771 ± 0.643 b |
0.30 | 8.000 ± 0.100 a | 19.984 ± 0.439 a | 25.819 ± 0.126 b | 12.217 ± 0.225 a | 9.433 ± 0.252 a | 24.547 ± 0.839 c |
Light Intensity (in μmol Photons m−2 s−1) | ||||||
520 | 8.000 ± 0.265 a | 22.240 ± 0.305 a | 25.741 ± 0.122 a | 12.233 ± 0.306 a | 9.533 ± 0.208 a | 22.252 ± 0.469 d |
390 | 7.700 ± 0.200 a | 14.696 ± 0.307 b | 25.565 ± 0.415 a | 12.250 ± 0.391 a | 9.333 ± 0.153 a | 30.456 ± 0.643 c |
260 | 7.900 ± 0.100 a | 10.948 ± 0.306 c | 25.545 ± 0.322 a | 12.400 ± 0.400 a | 9.300 ± 0.265 a | 33.907 ± 0.221 b |
130 | 8.100 ± 0.100 a | 7.879 ± 0.288 d | 25.100 ± 0.629 a | 12.200 ± 0.300 a | 9.233 ± 0.252 a | 37.487 ± 0.840 a |
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Metsoviti, M.N.; Papapolymerou, G.; Karapanagiotidis, I.T.; Katsoulas, N. Effect of Light Intensity and Quality on Growth Rate and Composition of Chlorella vulgaris. Plants 2020, 9, 31. https://doi.org/10.3390/plants9010031
Metsoviti MN, Papapolymerou G, Karapanagiotidis IT, Katsoulas N. Effect of Light Intensity and Quality on Growth Rate and Composition of Chlorella vulgaris. Plants. 2020; 9(1):31. https://doi.org/10.3390/plants9010031
Chicago/Turabian StyleMetsoviti, Maria N., George Papapolymerou, Ioannis T. Karapanagiotidis, and Nikolaos Katsoulas. 2020. "Effect of Light Intensity and Quality on Growth Rate and Composition of Chlorella vulgaris" Plants 9, no. 1: 31. https://doi.org/10.3390/plants9010031