The Effect of Salinity Variation on the Growth Performance, Physiological Response, and Nutrient Utilization of Seaweed Chaetomorpha linum as a Bioremediation Candidate

This study aims to analyze the effect of salinity variations on the physiological response, growth, chlorophyll synthesis, and survival rate of the seaweed Chaetomorpha linum as a bioremediation agent under controlled laboratory conditions. The study used a Completely Randomized Design (CRD) with nine salinity treatments, namely P1 (40 ppt), P2 (35 ppt), P3/control (30 ppt), P4 (25 ppt), P5 (20 ppt), P6 (15 ppt), P7 (10 ppt), P8 (5 ppt), and P9 (0 ppt), each with five replications for 30 days of maintenance (uniform initial biomass of 5 g). The parameters analyzed included absolute weight, Specific Growth Rate (SGR), Survival Rate (SR), dry biomass yield, thallus diameter, chlorophyll content, and water quality. Data were analyzed using analysis of variance (ANOVA) and continued with Duncan's test (α = 0.05). The results showed that salinity variation had a significant effect (P < 0.05) on all test parameters. Hyper-saline treatment of 40 ppt (P1) resulted in optimum performance with an absolute weight of 5.23 ± 3.61 g, SGR of 2.39 ± 1.10%/day, a survival score of 4 (Very Fresh), dry biomass yield of 8.89 ± 1.07%, and the highest chlorophyll content of 273 mg/100g. Hypo-saline conditions (P7–P9) triggered severe osmotic stress, cellular lysis, tissue bleaching, and negative growth, with the most critical/lethal condition in freshwater P9 (0 ppt). In conclusion, C. linum showed peak physiological performance at a salinity of 30–40 ppt, confirming that C. linum has great potential to be applied as a biofilter and bioremediation agent in coastal waters, open seas, and high to moderate salinity aquaculture areas

Bioremediation; C. linum; Chlorophyll; Growth Rate; Salinity

1. Pan, Y., Amenorfenyo, D. K., Dong, M., Zhang, N., Huang, X., Li, C., & Li, F. (2024). Effects of salinity on the growth, physiological and biochemical components of microalga Euchlorocystis marina. Frontiers in Marine Science, 11(May), 1–9. https://doi.org/10.3389/fmars.2024.1402071 [Google Scholar] [Crossref]

2. Tresnati, J., Yasir, I., Bestari, A. D., Yanti, A., Aprianto, R., & Tuwo, A. (2021). Effect of salinity on the growth of seaweed Gracilaria changii (Xia and Abbott, 1987). IOP Conference Series: Earth and Environmental Science, 763(1). https://doi.org/10.1088/1755-1315/763/1/012030 [Google Scholar] [Crossref]

3. Wynhorst, J., Chung, W. H., Fotedar, R., Vadiveloo, A., Moheimani, N. R., & Howieson, J. (2024). Growth and biochemical composition of green seaweed Chaetomorpha linum (O.F. Müller) Kützing (1845) cultured in a range of ionic profiles. Algal Research, 84(1845), 103769. https://doi.org/10.1016/j.algal.2024.103769 [Google Scholar] [Crossref]

4. Tsutsui, I., Miyoshi, T., Aue-umneoy, D., Songphatkaew, J., Meeanan, C., Klomkling, S., Sukchai, H., Pinphoo, P., Yamaguchi, I., Ganmanee, M., Maeno, Y., & Hamano, K. (2015). High tolerance of Chaetomorpha sp. to salinity and water temperature enables survival and growth in stagnant waters of central Thailand. International Aquatic Research, 7(1), 47–62. https://doi.org/10.1007/s40071-014-0092-4 [Google Scholar] [Crossref]

5. Aquilino, F., Paradiso, A., Trani, R., Longo, C., Pierri, C., Corriero, G., & de Pinto, M. C. (2020). Chaetomorpha linum in the bioremediation of aquaculture wastewater: Optimization of nutrient removal efficiency at the laboratory scale. Aquaculture, 523. https://doi.org/10.1016/j.aquaculture.2020.735133 [Google Scholar] [Crossref]

6. Ge, S., & Champagne, P. (2017). Cultivation of the Marine Macroalgae Chaetomorpha linum in Municipal Wastewater for Nutrient Recovery and Biomass Production. Environmental Science and Technology, 51(6), 3558–3566. https://doi.org/10.1021/acs.est.6b06039 [Google Scholar] [Crossref]

7. Mosquera-murillo, Z., & Peña-salamanca, E. J. (2016). Effect of salinity on growth of the green alga Caulerpa sertularioides (Bryopsidales, Chlorophyta) under laboratory conditions. Hidrobiológica, 26(2), 277–282. [Google Scholar] [Crossref]

8. Zailan, L. Z., Patadjai, R. S., & Balubi, A. M. (2019). Analisis Pertumbuhan Perbedaan Jenis Bibit Rumput Laut Kotoni (Kappaphycus alvarezii) Yang Dipelihara Pada Kondisi Perairan Berbeda. Media Akuatika, 4(4), 151–159. [Google Scholar] [Crossref]

9. Dengan, A., Budidaya, M., Berbeda, Y., Pesisir, D. I., Halimah, N., Harlina, H., & Kasnir, M. (2021). Dosen Program Studi Budidaya Perairan Fakultas Perikanan dan Ilmu Kelautan Universitas. 61–75. [Google Scholar] [Crossref]

10. Darmawan, A., Hambali, M., & Salam, A. R. (2020). Evaluation on Moisture Content of Eucheuma cottonii Seaweed Variety using Statistical Quality Control Approach. Industria: Jurnal Teknologi Dan Manajemen Agroindustri, 9(2), 99–108. https://doi.org/10.21776/ub.industria.2020.009.02.3 [Google Scholar] [Crossref]

11. Handayani, M., Nuzapril, M., Setya, D., & Putri, A. S. (2024). Screening of Active Compounds from Sargassum Seaweed Collected from Lampung Bay. 532–539. [Google Scholar] [Crossref]

12. Ajiningrum, P. S. (2019). Total Chlorophyll Pigment Content of Avicennia marina Leaves at Different Developmental Stages. STIGMA: Jurnal Matematika Dan Ilmu Pengetahuan Alam Unipa, 11(02), 52–59. https://doi.org/10.36456/stigma.vol11.no02.a1734 [Google Scholar] [Crossref]

13. Astija, Suleman, S. M., Bialangi, M. S., Indri Febriani, V., & Afiat, N. (2023). Biophotomicrograph, an Alternative Technique for Measuring Micro-Sized Biological Objects. International Journal of Innovative Science and Research Technology (Vol. 8, Issue 8). www.ijisrt.com [Google Scholar] [Crossref]

14. Standar Nasional Indonesia. (2010). Produksi rumput laut kotoni (Eucheuma cottonii) - Bagian 2: Metode long-line. Badan Standar Indonesia SNI 7579.2:2010, 2, 1–9. [Google Scholar] [Crossref]

15. Sorce, C., Persiano Leporatti, M., & Lenzi, M. (2018). Growth and physiological features of Chaetomorpha linum (Müller) Kütz. in high density mats. Marine Pollution Bulletin, 129(2), 772–781. https://doi.org/10.1016/j.marpolbul.2017.10.071 [Google Scholar] [Crossref]

16. Xing, R., Ma, W., Shao, Y., Cao, X., Chen, L., & Jiang, A. (2019). Factors that affect the growth and photosynthesis of the filamentous green algae, Chaetomorpha valida, in static sea cucumber aquaculture ponds with high salinity and high pH. PeerJ, 2019(2). https://doi.org/10.7717/peerj.6468 [Google Scholar] [Crossref]

17. Kladchenko, E. S., Lavrichenko, D. S., Bogacheva, E. A., & Chelebieva, E. S. (2025). Effects of hyposalinity stress on the physiological state of the marine microalgae Coccomyxa parasitica. Regional Studies in Marine Science, 90. https://doi.org/10.1016/j.rsma.2025.104443 [Google Scholar] [Crossref]

18. Gibson, V. L., Richards Donà, A., & Smith, C. M. (2023). Measuring tissue water potential in marine macroalgae via an updated Chardakov method. AoB PLANTS (Vol. 15, Issue 5). https://doi.org/10.1093/aobpla/plad055 [Google Scholar] [Crossref]

19. Rybak, A. S. (2018). Species of Ulva (Ulvophyceae, Chlorophyta) as indicators of salinity. Ecological Indicators (Vol. 85, pp. 253–261). https://doi.org/10.1016/j.ecolind.2017.10.061 [Google Scholar] [Crossref]

20. Xu, Y., & Lin, J. (2008). Effect of temperature, salinity, and light intensity on the growth of the green macroalga, chaetomorpha linum. Journal of the World Aquaculture Society, 39(6), 847–851. https://doi.org/10.1111/j.1749-7345.2008.00223.x [Google Scholar] [Crossref]

21. Gambichler, V., Zuccarello, G. C., & Karsten, U. (2021). Physiological responses to salt stress by native and introduced red algae in New Zealand. Algae, 36(2), 137–146. https://doi.org/10.4490/algae.2021.36.6.10 [Google Scholar] [Crossref]

22. Chelebieva, E. S., Lavrichenko, D. S., Bogacheva, E. A., Rylkova, O. A., Meger, Y. V., & Kladchenko, E. S. (2025). Cellular responses of the green parasitic microalga Coccomyxa parasitica to osmotic stress. Ecologica Montenegrina, 91, 105–116. https://doi.org/10.37828/em.2025.91.12 [Google Scholar] [Crossref]

23. Kazir, M., Abuhassira, Y., Robin, A., Nahor, O., Luo, J., Israel, A., Golberg, A., & Livney, Y. D. (2019). Extraction of proteins from two marine macroalgae, Ulva sp. and Gracilaria sp., for food application, and evaluating digestibility, amino acid composition and antioxidant properties of the protein concentrates. Food Hydrocolloids, 87, 194–203. https://doi.org/10.1016/j.foodhyd.2018.07.047 [Google Scholar] [Crossref]

24. Romanenko, E. A., Romanenko, P. A., Babenko, L. M., & Kosakovskaya, I. V. (2017). Salt stress effects on growth and photosynthetic pigments' content in algoculture of Acutodesmus dimorphus (Chlorophyta). International Journal on Algae, 19(3), 271–282. https://doi.org/10.1615/InterJAlgae.v19.i3.70 [Google Scholar] [Crossref]

25. Chen, B., & Zou, D. (2015). Altered seawater salinity levels affected growth and photosynthesis of Ulva fasciata (Ulvales, Chlorophyta) germlings. Acta Oceanologica Sinica, 34(8), 108–113. https://doi.org/10.1007/s13131-015-0654-3 [Google Scholar] [Crossref]

• Assessment of the Role of Artificial Intelligence in Repositioning TVET for Economic Development in Nigeria
• Teachers’ Use of Assure Model Instructional Design on Learners’ Problem Solving Efficacy in Secondary Schools in Bungoma County, Kenya
• “E-Booksan Ang Kaalaman”: Development, Validation, and Utilization of Electronic Book in Academic Performance of Grade 9 Students in Social Studies
• Analyzing EFL University Students’ Academic Speaking Skills Through Self-Recorded Video Presentation
• Major Findings of The Study on Total Quality Management in Teachers’ Education Institutions (TEIs) In Assam – An Evaluative Study