Antioxidant properties and polyphenolic content in terrestrial cyanobacteria

Abstract

Cell-free extracts of twenty terrestrial cyanobacteria were evaluated for their antioxidant properties in terms of free-radical scavenging (DPPH and ABTS) and metal chelating activity and deoxyribose protection. Extract of Anabaena constricta was the most prominent antioxidant agent (IC 50 for DPPH activity 0.91 mg ml -1 , ABTS 0.23 mg ml -1 , deoxyribose protection 0.63 mg ml -1 and Fe ?2 -ion chelating 0.9 mg ml -1 ). The extracts of cyanobacterial species contained high quantity of total phenol and total flavonoid that were supposed to impart prominent antioxidant properties. Cyanobacterial species also showed fairly high PAL activity. We reported varied quantities of polyphenolics gallic, chlorogenic, caffeic, vanillic and ferulic acids and flavonoids rutin, quercetin and kaempferol in cyanobacterial extracts. The presence of these polyphenolics was linked with the free radical scavenging, metal chelating and antioxidative damage protecting properties of the organisms. Cyanobacteria are the most feasible, promising and alternative candidates for searching out new chemical leads for industrial applications in pharmaceuticals, neutraceuticals and biomolecules of importance. Presence of biomolecules such as polyphenolics and their connection with the prominent biological functions (e.g., antioxidant properties) make these organisms a potential source of secondary metabolites with predominant biological activities. Additionally, dominant presence of polyphenols as antioxidant agents in cyanobacterial species may reflect their adaptation strategies against abiotic stresses for their ecological success in different habitats.

Biocatalytic hydrogenation of the C=C bond in the enone unit of hydroxylated chalcones—process arising from cyanobacterial adaptations

“…Because of their phototrophic lifestyle and constant exposure to high oxygen and radical stresses, these biota have a high capability for producing plentiful efficient protective chemicals against oxidative and radical stressors and exhibit adaptive responses to oxidative stresses by stimulating their intrinsic antioxidant defence systems based on mediator compounds, including polyphenolic substances (Babić et al 2016). Previously published data indicate that the phenolic acids and flavonoids in cyanobacterial cells may be responsible for their antioxidant properties (Singh et al 2017a), and thus a higher content of phenolics in cyanobacterial species may be presumed as an adaptation strategy of these organisms against abiotic stresses in their specific habitats. Therefore, the properties of these organisms may also include functional values such as free-radical quenching, metal chelation and ROS-scavenging activity (Singh et al 2017a).…”

“…Previously published data indicate that the phenolic acids and flavonoids in cyanobacterial cells may be responsible for their antioxidant properties (Singh et al 2017a), and thus a higher content of phenolics in cyanobacterial species may be presumed as an adaptation strategy of these organisms against abiotic stresses in their specific habitats. Therefore, the properties of these organisms may also include functional values such as free-radical quenching, metal chelation and ROS-scavenging activity (Singh et al 2017a). Our evaluations are consistent with literature reports showing that metabolites such as flavonoids are involved in the defence system of cyanobacteria against adverse conditions (Singh et al 2017b).…”

“…Moreover, several inherent features of cyanobacteria, such as oxygenic photosynthesis, amenability to genetic engineering and capacity to survive in extreme habitats or under chemical stress, make them prominent cell factories for targeted biotransformations (Xue and He 2015). We hypothesise then that organisms that produce phenylpropanoids, which are also precursors of flavonoids (Goiris et al 2014; Singh et al 2017a), must possess active enzymatic pathways that enable them to transform these compounds according to cellular needs.…”

mRNA Expression and Biomarker Responses in Perch at a Biomonitoring Site in the Baltic Sea – Possible Influence of Natural Brominated Chemicals

“…This large group of compounds, many of which have probiotic properties, have been studied extensively for their role in food and health (Moon et al, 2006;Viskupciova et al, 2008). Recently, it has been shown that microalga, including cyanobacteria, contain flavonoids (Goiris et al, 2014;Singh et al, 2017). In the Baltic Sea, the blooming of microalga frequently occurs.…”

Induction of Antioxidative Activity and Antioxidant Molecules in the Halotolerant Cyanobacterium Halothece sp. PCC7418 by Temperature Shift

“…3 Recently, several reports have described the antioxidative activities and properties of extracts derived from terrestrial and freshwater cyanobacteria. [4][5][6][7] However, the relationship between the antioxidative activities and the antioxidant-generating capacities of these cyanobacterial extracts is not fully understood. Moreover, a much needed resource for antioxidants, such as extremophilic cyanobacteria, has not yet been reported.…”