Exploring the Diversity of Red Microalgae for Exopolysaccharide Production

Abstract

Microalgae constitute a remarkable biological diversity but a limited number of them have been the object of study for their ability to produce exoplysaccharides (EPS). Among them, the red marine microalgae Porphyridium or Rhodella produce sulphated EPS, exhibiting some biological activities with potential interest in the pharmaceutical and cosmetic industries. EPS from Porphyridium and Rhodella being relatively similar in their composition, it has long been considered that all the red microalgae produced similar EPS and no attention was paid to other red microalgae. The objective of our work was then to explore the diversity of red microalgae for the production of EPS, focusing in this first step on the screening of the strains for their ability to produce EPS and preliminary structural characterization. The study was conducted with 11 microalgae strains belonging to the proteorhodophytina subphylum. All microalgae were able to produce EPS, released in the culture medium (strains belonging to Porphyridiophyceae and Rhodellophyceae classes) or remaining bound to the cells (strains from Stylonematophyceae class). The analysis of monosaccharides composition was found significantly different, with for instance high levels of glucuronic acids in the EPS from C. japonica and N. cyanea, but also strong differences in the sulphation degrees of polymers (between 1.2 and 28.7% eq. SO4).

Tailored Fabrication of Plasmonic Film Light Filters for Enhanced Microalgal Growth and Biomass Composition

“…Haxo and others have extensively characterized the photosynthetic action spectra of different microalgal species to study the effect of the preferential absorption of light at different wavelengths of the electromagnetic spectrum on algal growth [ 22 ]. The primary groups of microalgae, based on preferential light absorption, include cyanophyta (blue-green microalgae) like Arthrospira platensis (Spirulina) and Crocosphaera subtropica , chlorophyta (green microalgae like Chlorella vulgaris and Chlamydomonas reinhardtii ), and rhodophyta (red algae) like Porphyridium cruentum and Flintiella sanguinaria , among others [ 22 , 23 , 24 , 25 ]. The preferential light wavelengths for each microalga of this group are documented in the literature.…”

Enhanced growth and metabolite production from a novel strain of Porphyridium sp

“…Drira et al [ 16 ] found an average growth rate and a doubling time of 0.055 day −1 and 12.6 days, respectively, for Porphyridium sordidum cultured in Pm medium. However, because these parameters are not usually computed and because it is highly influenced by culture conditions as salinity and light availability, it is exceedingly challenging to compare results from one study to another [ 68 ]. The growth rate of Porphyridium sp.…”

Antioxidant and Anticancer Potential of Extracellular Polysaccharide from Porphyridium aerugineum (Rhodophyta)

“…Among the numerous metabolites synthesized by microalgae that exhibit biological activities are sulphated polysaccharides (sPS). Rich and sustainable source of sPS are various species of red microalgae [4]. The cells of red microalgae are encased in a matrix of these polysaccharides.…”

“…Indeed, sEPS produced by red microalgae have been the subject of a growing number of publications regarding their physicochemical properties as well as their biological activities, such as antioxidant, anti-inflammatory, antiviral, antifungal, antibacterial, anticancer, immunomodulatory, antiaging, etc. [4,8,9]. The great potential of sEPS from marine microalgae, including red microalgae, to be used as nutraceuticals, therapeutic agents or cosmetics, are approached in the review article by [10].…”