Phenolic Profile and Antioxidant Activity of Crude Extracts from Microalgae and Cyanobacteria Strains

Abstract

Aqueous and methanolic extracts of several microalgae (Ankistrodesmus sp., Spirogyra sp., Euglena cantabrica, and Caespitella pascheri) and cyanobacteria (Nostoc sp., Nostoc commune, Nodularia spumigena, Leptolyngbya protospira, Phormidiochaete sp., and Arthrospira platensis) were screened for their radical scavenging activity against the stable radical 1,1-diphenyl-2-picrylhydrazyl. Despite the fact that water was a more efficient solvent to extract greater amount of extractable substances, it seems that methanol was more efficient to extract a selected group of compounds with a higher antioxidant activity. In addition, the identification of 4 simple phenolics (gallic, syringic, protocatechuic, and chlorogenic acids) and the flavonoids (+) catechin and (-) epicatechin was carried out by using reverse phase high performance liquid chromatography. The strain Euglena cantabrica showed the highest concentration of phenolic compounds, particularly gallic and protocatechuic acids (5.87 and 2.97 mg per gram of dried biomass, resp.). Aqueous and methanolic extracts of microalgae Euglena cantabrica also exhibited the highest antioxidant activity, probably due to the presence of the high contents of phenolics.

Functional Composition, Nutritional Properties, and Biological Activities of MoroccanSpirulinaMicroalga

“…A chromatographic separation method (HPLC-DAD/MS) was developed for simultaneous identi cation and quanti cation of phenolic acids and avonoids in Spirulina reported to possess vital nutritional and biological activities [68]. A total of twenty phenolic acid and avonoid compounds were properly identi ed and quanti ed compared with phenolic standards (retention times, mass spectra, and their fragmentations) within 30 min.…”

Antioxidant Properties of Popular Turmeric(Curcuma longa)Varieties from Bangladesh

“…Free radicals have been implicated in the aetiology of several human ailments. Antioxidant activities of several therapeutic compounds like ascorbic acids possess significant properties which could ameliorate the effects seen [31]. Turmeric and its constituents have been credited to have many therapeutic benefits where antioxidants are believed to play the major therapeutic role related to the beneficial effects [26].…”

Effects of flask configuration on biofilm growth and metabolites of intertidal Cyanobacteria isolated from a mangrove forest

“…CBE were initially solubilized in 10% methanol (MeOH) at 10 mg ml −1 (Jerez‐Martel et al . ). Aliquots of 50 μ l of CBE or solvent (negative control) and 30 μ l of 3·3 × strength MH broth were added to the appropriate microtitre wells.…”

“…After 12-18 h, the microbial cultures were harvested and the turbidity adjusted to 10 6 CFU per ml. CBE were initially solubilized in 10% methanol (MeOH) at 10 mg ml À1(Jerez-Martel et al 2017). Aliquots of 50 ll of CBE or solvent (negative control…”