Morpho-anatomical, and chemical characterization of some calcareous Mediterranean red algae species

Abstract

Climatic changes are anticipated to have a detrimental effect on calcifying marine species. Calcareous red algae may be especially vulnerable to seasonal variations since they are common and essential biologically, but there is little research on the morpho-anatomical, and chemical characterization of such species. This study conducted the seasonal investigation of the three dominant Mediterranean calcified red algae. Morphological and 18S rRNA analysis confirmed the identification of collected species as Corallina officinalis, Jania rubens, and Amphiroa rigida. In general, C. officinalis was represented in the four seasons and flourishing maximum in autumn (70% of total species individuals). While J. rubens species was represented in winter, autumn, and spring and completely absent in summer. A. rigida was abundant only in the summer season by 40%. A full morphological and anatomical description of these species were examined, and their chemical compositions (carbohydrate, protein, lipid, pigments, and elements content) were assessed in different seasons, where carbohydrates were the dominant accumulates followed by proteins and lipids. Pearson correlation analysis confirmed a positive correlation between salinity level and nitrogenous nutrients of the seawater with the pigment contents (phycobiliproteins, carotenoids, and chlorophyll a) of the studied seaweeds. The results proved that calcified red algae were able to deposit a mixture of calcium carbonates such as calcite, vaterite, calcium oxalate, calcite-III I calcium carbonate, and aragonite in variable forms depending on the species.

Unveiling the Potential of Algal Extracts as Promising Antibacterial and Antibiofilm Agents against Multidrug-Resistant Pseudomonas aeruginosa: In Vitro and In Silico Studies including Molecular Docking

“…These extracts have demonstrated positive antibacterial activity against diverse strains of pathogens [ 18 , 38 ]. The variance in bioactive compounds can be attributed to factors such as the solvent type, extraction method, and the season during which the algae were collected [ 39 , 40 ]. Our own findings revealed that the methanol extract of A. platensis and the acetone extract of P. scopulorum exhibited no antimicrobial activity.…”

Macroalgae Bioplastics: A Sustainable Shift to Mitigate the Ecological Impact of Petroleum-Based Plastics

“…Red algae, or Rhodophyta, are diverse eukaryotic organisms that inhabit freshwater lakes and marine environments, showcasing a distinctive red color from phycoerythrin, carotenoids, and chlorophyll a pigment [95]. Their starch and galactan sulfate polymer content positions red algae as a viable feedstock for bioplastic production [96].…”

Exploring the Prospects of Fermenting/Co-Fermenting Marine Biomass for Enhanced Bioethanol Production

“…Macroalgae and phytoplankton are predominant contributors to marine primary production [44,45]. Despite once being considered predecessors of land plants, algae lack the characteristic plant structures such as stems, leaves, and roots.…”

“…Macroalgae have a complex lifecycle displaying annual and perennial life histories, alternation of generation, as well as asexual and sexual reproduction. They are a rich source of bioactive compounds, including polysaccharides, proteins, lipids, vitamins, minerals, and secondary metabolites [45]. The composition of these bioactive compounds varies among different species, as well as based on growth factors such as environmental conditions, growth stage, and geographical location [89,90].…”