Background: Phycocyanin is an algae-derived protein, which binds to pigment for harvesting light. It has been reported in various different species, including that of red algae, dinoflagellates, and cryptophyta. Importantly, phycocyanin has enormous applications, including cosmetic colorant, food additive, biotechnology, diagnostics, fluorescence detection probe, an anticancer agent, anti-inflammatory, immune enhancer, etc. In addition, several different algae were utilized for the isolation of cyano-phycocyanin (C-PC), but most of the purification methods consist of several steps of crude extraction.Aim: To isolate C-PC from a new source of microalgae with better purity level and to evaluate its antimicrobial, algicidal, and antiradical activities.Methods: Biological activity, permeability, pharmacokinetics, and toxicity profile of C-PC were predicted by in silico studies. C-PC was purified and isolated by using ammonium sulphate precipitation, ion-exchange chromatography and gel-filtration chromatography. C-PC was characterized by SDS-PAGE and elution profile (purity ratio) analysis. Antimicrobial and algicial activities of C-PC were evaluated by the microtitre plate based assays. Antiradical activity of C-PC was evaluated by DPPH- and ABTS*+ radical scavenging assays.Conclusion: C-PC was extracted from Oscillatoria minima for the first time, followedby its quantitative as well qualitative evaluation, indicating a new alternative source ofthis important protein. Furthermore, the antimicrobial, algicidal, and antiradical activities of the isolated C-PC extract have been demonstrated by both in silico as well as in vitro methods.