Neila Annabi-Trabelsi

By Sana Gammoudi, Ines Dahmen-Ben Moussa, Neila Annabi-Trabelsi, Habib Ayadi and Wassim Guermazi

With the demand for bioproducts that can provide benefits for biotechnology sectors like pharmaceuticals, nutraceuticals, and cosmeceuticals, the exploration of microalgal products has turned toward extremophiles. This chapter is intended to provide an insight to most important molecules from halotolerant species, the cyanobacteria Phormidium versicolor NCC-466 and Dunaliella sp. CTM20028 isolated from Sfax Solar Saltern (Sfax) and Chott El-Djerid (Tozeur), Tunisia. These microalgae have been cultured in standard medium with a salinity of 80 PSU. The in vitro antioxidant activities demonstrated that extremolyte from Dunaliella and Phormidium as, phycocaynin, lipids, and polyphenol compound presents an important antioxidant potential.

Part of the book: Antioxidants

By Sana Gammoudi, Neila Annabi-Trabelsi, Mariem Bidhi, Nouha Diwani, Amira Rekik, Hajer Khmekhem, Habib Ayadi, Wassim Guermazi and Jannet Elloumi

The saltern of Sfax is a thalasso haline paralic ecosystem were the salinity ranged from 45 to 450 PSU. The microalgae distribution of saltern showed a spatial ecological succession. The specific richness of microalgae decreased with the salinity, accounting 37, 17 and 5 species at three level of salinity from 40 to 80, 80 to 200 and 200 to 450 PSU, respectively. To better understand the behavior of the hyper-halo tolerant microalgae, three autotrophic species Halamphora sp. SB1 MK575516 (Diatom), Phormidium versicolor NCC-466 (Cyanophyceae) and Dunaliella salina (Chlorophyceae) were isolated from each level of salinity and they are grown in batch in artificial seawater at laboratory scale. Growth and metabolites synthesized by these microalgae were assessed. Salinity reacts on the physiology of these three species which possess mechanisms of resistance to more or less effective stresses and generally by the synthesis of different biomolecules such as pigments, sugars, proteins and fatty acids.

Part of the book: Progress in Microalgae Research

By Neila Annabi-Trabelsi, Mohammad Ali, Genuario Belmonte, Habib Ayadi and Wassim Guermazi

The Gulf of Gabès, located in southern Tunisia, is a distinct and ecologically significant area in the Mediterranean Sea. Unfortunately, this dynamic marine ecosystem is experiencing cultural eutrophication, a process where water enrichment with nutrients like phosphorus and nitrogen salts leads to excessive algae growth, disrupting the ecological equilibrium and degrading water quality. In the Gulf of Gabès, key sources of nutrient pollution include industrial discharges, urbanization and agriculture. Eutrophication’s effects here include harmful algal blooms, oxygen depletion, and declining water quality, upsetting the marine ecosystem’s balance and impacting both fish and aquatic life. Nutrient enrichment interacts with trace metal pollution, overfishing and climate change. Future research must acknowledge and consider the complex interactions among these variables. Efforts in the Gulf of Gabès to address eutrophication involve tighter industrial regulations, enhanced agriculture and improved wastewater management, all crucial for preserving the marine environment’s integrity and ensuring sustainability for the future.

Part of the book: Marine Ecosystems