Plant, Algae, and Environment

Plant, Algae, and Environment

Effects of Zinc on Some Physiological and Biochemical Parameters of Dunaliella salina

Document Type : Original Article

Authors
Seyed Mehdi Razavi
Leila Bakhshi
Maryam Mosavi
Alireza Ghasemian
Mina Khodayari
Department of Biology, University of Mohaghegh Ardabili,West Azerbaijan, Iran
10.48308/pae.2026.244255.1142
Abstract
Recently, the use of algae as food and medicinal sources has gained significant attention. Heavy metals are recognized as major environmental pollutants due to their inherent toxicity. Because of their non-biodegradability and environmental persistence, these pollutants pose serious risks to both ecosystems and the health of living organisms. Algae have recently attracted considerable interest as valuable sources of food and bioactive compounds. Zinc (Zn) serves as a critical micronutrient in algal cells, contributing to enzymatic activity, photosynthetic processes, and overall cellular metabolism.This study evaluated the effects of different Zn concentrations (0.03, 0.06, 0.09, 0.25, and 0.5 μg/mL) on the physiological and biochemical characteristics of Dunaliella salina using a completely randomized design with three replications. The results showed that 0.03 μg/mL Zn significantly enhanced photochemical efficiency (50.76%), chlorophyll a (154.5%), chlorophyll b (88.88%), protein content (13.86%), soluble sugars (89.47%), and catalase activity (71.42%) compared with the control. In contrast, the highest carotenoid accumulation (92.85%) was observed at 0.5 μg/mL Zn. Proline, total amino acids, ascorbate peroxidase, and polyphenol oxidase increased progressively with Zn concentration, reaching maximum values at 0.5 μg/mL and exceeding the control by 68.18%, 88.88%, 88.46%, and 90.38%, respectively. Zinc also affected carbohydrate metabolism in a biphasic manner, causing an initial increase followed by a decline in soluble sugar levels. Overall, the findings indicate that Zn enhances photosynthetic performance, antioxidant defense, and metabolic activity in D. salina, while the species exhibits high sensitivity to changes in Zn availability. These characteristics highlight its potential as a reliable bioindicator for monitoring heavy-metal contamination in aquatic environments. These adaptive responses also may hold significance for biotechnological applications, such as the production of valuable secondary metabolites or the utilization of algae in heavy metal bioremediation strategies.
Keywords
Dunaliella salina
Zn strees
Antioxidant defense
Heavy metal bioremediation
 Aebi, H. (1984) ‘Catalase in vitro’, Methods in Enzymology, 105, pp. 121–126. https://doi.org/10.1016/S0076-6879(84)05016-3.
Alirahimi, N., Kordenaeej, A., Rezaei, A. and Talei, D. (2022) ‘Changes in growth, beta-carotene production, traits, and protein banding patterns in Dunaliella salina microalgae in the presence of colchicine’, Journal of Marine Science and Technology, 20(4), pp. 86–94. https://doi.org/10.22113/jmst.2016.38962.
Bates, L.S., Waldren, R.P. and Teare, I.D. (1973) ‘Rapid determination of free proline for water-stress studies’, Plant and Soil, 39(1), pp. 205–207. https://doi.org/10.1007/BF00018060.
Bradford, M.M. (1976) ‘A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding’, Analytical Biochemistry, 72(1–2), pp. 248–254. https://doi.org/10.1006/abio.1976.9999.
Broadley, M.R., White, P.J., Hammond, J.P., Zelko, I. and Lux, A. (2007) ‘Zn in plants’, New Phytologist, 173(4), pp. 677–702. https://doi.org/10.1111/j.1469-8137.2007.01996.x.
Cakmak, I. (2000) ‘Possible roles of Zn in protecting plant cells from damage by reactive oxygen species’, New Phytologist, 146(2), pp. 185–205. https://doi.org/10.1046/j.1469-8137.2000.00630.x.
Dubois, M., Gilles, K.A., Hamilton, J.K., Rebers, P.A. and Smith, F. (1956) ‘Colorimetric method for determination of sugars and related substances’, Analytical Chemistry, 28(3), pp. 350–356. https://doi.org/10.1021/ac60111a017.
Elleuch, J., Hmani, R., Drira, M., Michaud, P., Fendri, I. and Abdelkafi, S. (2021) ‘Zinc biosorption by Dunaliella sp. AL-1: Mechanism and effects on cell metabolism’, Science of the Total Environment, 773, 145024. https://doi.org/10.1016/j.scitotenv.2021.145024.
Folgar, S., Torres, E., Pérez-Rama, M., Cid, A., Herrero, C. and Abalde, J. (2009) ‘Dunaliella salina as a marine microalga highly tolerant to, but a poor remover of, cadmium’, Journal of Hazardous Materials, 165(1–3), pp. 486–493. https://doi.org/10.1016/j.jhazmat.2008.10.004.
Gao, M., Ling, N., Tian, H., Guo, C. and Wang, Q. (2024) ‘Toxicity, physiological response, and biosorption mechanism of Dunaliella salina to copper, lead, and cadmium’, Frontiers in Microbiology, 15, 1374275. https://doi.org/10.3389/fmicb.2024.1374275.
Hamed, S.M., Zinta, G., Klöck, G., Asard, H., Selim, S. and AbdElgawad, H. (2017) ‘Zn-induced differential oxidative stress and antioxidant responses in Chlorella sorokiniana and Scenedesmus acuminatus’, Ecotoxicology and Environmental Safety, 140, pp. 256–263. https://doi.org/10.1016/j.ecoenv.2017.02.039.
Kabata-Pendias, A. (2011) Trace Elements in Soils and Plants. 4th edn. Boca Raton, FL: CRC Press.
Lichtenthaler, H.K. (1987) ‘Chlorophylls and carotenoids: Pigments of photosynthetic biomembranes’, Methods in Enzymology, 148, pp. 350–382. https://doi.org/10.1016/0076-6879(87)48036-1.
Massyuk, N.P. (1996) ‘Mass culture of the carotene-bearing alga Dunaliella salina Teod.’, Ukrainian Botanical Journal, 23, pp. 12–19.
Maxwell, K. and Johnson, G.N. (2000) ‘Chlorophyll fluorescence—A practical guide’, Journal of Experimental Botany, 51(345), pp. 659–668. https://doi.org/10.1093/jexbot/51.345.659.
Mayer, A.M. and Harel, E. (1979) ‘Polyphenol oxidases in plants’, Phytochemistry, 18(2), pp. 193–215. https://doi.org/10.1016/0031-9422(79)80057-6.
Mishra, A. and Jha, B. (2011) ‘Antioxidant response of the microalga Dunaliella salina under salt stress’, Botanica Marina, 54(2), pp. 195–199. https://doi.org/10.1515/BOT.2011.027.
Moore, S. and Stein, W.H. (1963) ‘Methods for amino acid analysis’, Analytical Chemistry, 35(13), pp. 1965–1970. https://doi.org/10.1021/ac60205a045.
Nagajyoti, P.C., Lee, K.D. and Sreekanth, T.V.M. (2010) ‘Heavy metals, occurrence and toxicity for plants: A review’, Environmental Chemistry Letters, 8, pp. 199–216. https://doi.org/10.1007/s10311-010-0297-8.
Nakano, Y. and Asada, K. (1981) ‘Hydrogen peroxide is scavenged by ascorbate-specific peroxidase in spinach chloroplasts’, Plant and Cell Physiology, 22(5), pp. 867–880. https://doi.org/10.1093/oxfordjournals.pcp.a076232.
Palomares, A.J., Rubio, F. and Florencio, F.J. (2004) ‘Role of carbonic anhydrase in inorganic carbon uptake by phytoplankton’, Biochemical Journal, 382(2), pp. 353–361. https://doi.org/10.1042/BJ20040484.
Pilon, M. and Várkonyi, A. (2017) ‘Plant metal homeostasis—Challenges and opportunities’, Current Opinion in Plant Biology, 38, pp. 151–159. https://doi.org/10.1016/j.pbi.2017.05.004.
Rathore, D., Singh, A.K. and Pandey, A. (2015) ‘Effect of Zn on growth and β-carotene production in Dunaliella salina’, Journal of Environmental Biology, 36(1), pp. 141–147.
Riahi, H. (2002) Algology. 2nd edn. Tehran: Alzahra University Press.
Roy, U.K., Nielsen, B.V. and Milledge, J.J. (2021) ‘Tuning Dunaliella tertiolecta for enhanced antioxidant production by modification of culture conditions’, Marine Biotechnology, 23(3), pp. 482–500. https://doi.org/10.1007/s10126-021-10039-7.
Salehipour-Bavarsad, F., Riahi, H., Hejazi, M.A. and Shariatmadari, Z. (2022) ‘Screening terrestrial and aquatic strains of Dunaliella from the eco-taxonomical perspective: A comparative study on fatty acid compositions as habitat indicators’, Journal of Applied Phycology, 34(1), pp. 461–474. https://doi.org/10.1007/s10811-021-02645-3.
Sui, Y., Mazzucchi, L., Acharya, P., Xu, Y., Morgan, G. and Harvey, P.J. (2021) ‘A comparison of β-carotene, phytoene, and amino acid production in Dunaliella salina DF15 (CCAP 19/41) and Dunaliella salina CCAP 19/30 under different light wavelengths’, Foods, 10(11), 2824. https://doi.org/10.3390/foods10112824.
Sunda, W.G. and Huntsman, S.A. (1995) ‘Effect of free metal ion concentration on the survival of the marine diatom Thalassiosira weissflogii’, Limnology and Oceanography, 40(3), pp. 512–517. https://doi.org/10.4319/lo.1995.40.3.0512.
Wang, W.-X. (2002) ‘Interactions of trace metals and different marine food chains’, Marine Ecology Progress Series, 243, pp. 295–309. https://doi.org/10.3354/meps243295.
Whittaker, R.H. and Margulis, L. (1978) ‘Protist classification and the kingdoms of organisms’, BioSystems, 10(1–2), pp. 3–18. https://doi.org/10.1016/0303-2647(78)90006-3.
Wongsnansilp, T., Juntawong, N. and Wu, Z. (2018) ‘Effects of phosphorus on the growth and chlorophyll fluorescence of a Dunaliella salina strain isolated from saline soil under nitrate limitation’, Journal of Biological Research-Bollettino della Società Italiana di Biologia Sperimentale, 91(1). https://doi.org/10.4081/jbr.2018.7541.
Xiong, Z.T. (2006) ‘Bioaccumulation and physiological effects of excess Zn in plants’, Reviews of Environmental Contamination and Toxicology, 186, pp. 67–113. https://doi.org/10.1007/0-387-32883-2-3.
Plant, Algae, and Environment
Volume 10, Issue 3
DOi
2026
Pages 37-48