Antioxidant and Cytoprotective Properties of Cyanobacteria: Potential for Biotechnological Applications

Abstract

Antioxidant compounds from cyanobacteria may constitute a natural alternative to current synthetic antioxidants, which contain preservatives and suspected toxicity. In this work, we evaluate the antioxidant potential of cyanobacterial strains of distinct species/genus isolated from freshwater (n = 6), soil (n = 1) and wastewater (n = 1) environments. Lyophilized biomass obtained from in-vitro cultures of those strains was extracted with ethanol and methanol. The antioxidant potential was evaluated by chemical (DPPH scavenging method, β-carotene bleaching assay, determination of total phenolic and total flavonoid compounds) and biological (H2O2-exposed HEK293T cell line model) approach. Some strains showed high yields of antioxidant activity by the DPPH assay (up to 10.7% IP/20.7 TE μg/mL) and by the β-carotene bleaching assay (up to 828.94 AAC), as well as significant content in phenolic (123.16 mg EAG/g DW) and flavonoid (900.60 mg EQR/g DW) compounds. Normalization of data in a “per cell” or “per cell volume” base might facilitate the comparison between strains. Additionally, most of the cyanobacterial extracts conferred some degree of protection to HEK293T cells against the H2O2-induced cytotoxicity. Freshwater Aphanizomenon gracile (LMECYA 009) and Aphanizomenon flos-aquae (LMECYA 088), terrestrial Nostoc (LMECYA 291) and wastewater Planktothrix mougeotii (LEGE 06224) seem to be promising strains for further investigation on cyanobacteria antioxidant potential.

Naturally Occurring Functional Ingredient from Filamentous Thermophilic Cyanobacterium Leptolyngbya sp. KC45: Phytochemical Characterizations and Their Multiple Bioactivities

“…SI-SM [ 41 ], the methanolic and ethanolic extracts of Leptolyngbya sp. LMECYA 173 [ 8 ], and the diethyl ether extracts of Leptolyngbya sp. DEEL-3 [ 15 ], can effectively neutralize the DPPH free radical to a more stable form by providing IC 50 values of 0.08–50.0 mg/mL.…”

“…Many of the secondary metabolites produced by cyanobacteria are powerful antioxidants that may neutralize reactive oxygen species (ROS). These include polyphenols such as phenolic acids and flavonoids, as well as pigments such as chlorophylls and carotenoids [ 8 ]. Due to the higher yields and the use of non-arable land in cultivation, cyanobacteria are said to be superior and an excellent source of health-promoting bioactive compounds compared with other edible plants [ 4 ].…”

“…[ 9 ]. The phytochemical profiling of cyanobacteria is rather similar to that of medicinal plants and other types of algae; in particular, it is predominately made up of pigments and polyphenols [ 8 ]. In fact, a wide variety of bioactivities have been described for these compounds.…”

Novel Active Food Packaging Films Based on Whey Protein Incorporated with Seaweed Extract: Development, Characterization, and Application in Fresh Poultry Meat

“…Its initiated by the formation of free peroxyl radicals, which will react with unsaturated fatty acids, forming lipid hydroperoxides. Antioxidant compounds may inhibit lipid oxidation of the unsaturated fats by prevent the formation of free peroxyl radicals and the formation of lipid hydroperoxides [51][52][53].…”

The 6th Iberian and 2nd Ibero-American Cyanotoxin Congress CIC2019

“…The most fascinating characteristic of cyanobacteria is probably their capacity to produce not only a vast number of harmful compounds, but also high concentrations of antioxidants, cytoprotectors, pigments, and other biotechnologically interesting chemicals [ 19 ]. The biochemistry of these organisms remains quite unknown, but several new potentially useful molecules have been recently identified and named [ 20 ], and the list of beneficial activities continues to grow [ 21 ].…”