Total Phenolic Content, Biomass Composition, and Antioxidant Activity of Selected Marine Microalgal Species with Potential as Aquaculture Feed

Abstract

There has been growing interest in microalgal biomolecules for health and cosmetics, as well as in the use of microalgae as aquaculture feed due to the need to replace fishmeal and fish oil with sustainable yet equally nutritious alternatives. Aim of this study is to evaluate the potential of five marine microalgal species, namely Chlorella minutissima, Dunaliella salina, Isochrysis galbana, Nannochloropsis oculata and Tisochrysis lutea, for the co-production of antioxidants and aquaculture feed. Batch cultivation was performed under saturating light intensity and continuous aeration. Freeze-dried biomass was extracted sequentially with water and methanol and evaluated for phenolic content and antioxidant activity, as well as proximate composition and fatty acid profile. Methanolic extracts of C. minutissima presented the highest phenolic content, measured with the Folin–Ciocalteu assay, and antioxidant activity. However, HPLC and LC-MS showed the presence of non-pigment compounds only in T. lutea. Total phenolic content and antioxidant activity were correlated to chlorophyll content. N. oculata and T. lutea were rich in eicosapentaenoic acid and docosahexaenoic acid, respectively, as well as in protein. In conclusion, N. oculata and T. lutea are suitable candidates for further optimization, while the data presented suggest that pigment effects on the Folin–Ciocalteu method require reconsideration.

Therapeutic effect of marine bioactive substances against periodontitis based on in vitro, in vivo, and clinical studies

“…Nannochloropsis oculata, one of the green microalgae, has been explored for functional food, nutraceutical, pharmacological agents, and aquaculture feed application (Andriopoulos et al, 2022;Hussein et al, 2020;Samarakoon et al, 2013). Therefore, Revianti et al investigated whether N. oculata extract shows a pharmacological effect on periodontitis using an A. actinomycetemcomitans-infected periodontitis rat model (Revianti et al, 2020).…”

Peningkatan Kadar Fenolik Total dari Chlorella sp. Menggunakan Cekaman Radiasi Ultraviolet-B

“…Pemanenan biomassa dilakukan setelah Chlorella sp. memasuki fase stasioner, yaitu 1 hari setelah puncak pertumbuhan (Andriopoulos et al, 2022). Sampel mikroalga yang telah diberikan larutan aluminium sulfat dihomogenkan selama 30 menit, kemudian wadah kaca ditutup dengan plastic wrap dan didiamkan selama 1 malam.…”

Extraction and Characterization of Bioactive Compounds from Diverse Marine Microalgae and Their Potential Antioxidant Activities

“…Previous research has systematically characterized these compounds in diverse marine microalgal strains, and unveiled their presence and potential applications, including from Chlorella minutissima, Isochrysis galbana, Nannochloropsis oculata, Tisochrysis lutea, and Dunaliella salina. [8] It is worth noting, however, that a subset of phenolics, specifically the bound phenolics, present a unique challenge in their study due to their interactions with various cell wall components like polysaccharides and proteins, which render them non-extractable without prior hydrolysis. Although bound phenolics are hypothesized to exhibit a more sustainable activity profile compared to their free counterparts, their binding properties imped comprehensive research efforts and add an extra layer of complexity to their study.…”

“…Phenolics, a category encompassing phenolic acids, flavonoids, and lignans, stand out as some of the most pivotal secondary metabolites derived from marine microalgae. Previous research has systematically characterized these compounds in diverse marine microalgal strains, and unveiled their presence and potential applications, including from Chlorella minutissima , Isochrysis galbana , Nannochloropsis oculata , Tisochrysis lutea , and Dunaliella salina [8] . It is worth noting, however, that a subset of phenolics, specifically the bound phenolics, present a unique challenge in their study due to their interactions with various cell wall components like polysaccharides and proteins, which render them non‐extractable without prior hydrolysis.…”