Evidence map›Paper›PMID 41667765›Full record

ArticleWorld journal of microbiology & biotechnology2026

Structural characterization and free radical scavenging potential of phycocyanin isolated from the rice-field cyanobacterium Dolichospermum spiroides HKAR-23.

Sapana Jha, Varsha K Singh, Ashish P Singh, Rajeshwar P Sinha

Abstract read
PubMed Publisher
In one paragraph

Article in World journal of microbiology & biotechnology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

4 authors.

Sapana JhaLaboratory of Photobiology and Molecular Microbiology, Department of Botany, Institute of Science, Banaras Hindu University, Varanasi, 221005, India.ORCID http://orcid.org/0009-0002-0847-4385
Varsha K SinghLaboratory of Photobiology and Molecular Microbiology, Department of Botany, Institute of Science, Banaras Hindu University, Varanasi, 221005, India.ORCID http://orcid.org/0000-0002-7856-9614
Ashish P SinghLaboratory of Photobiology and Molecular Microbiology, Department of Botany, Institute of Science, Banaras Hindu University, Varanasi, 221005, India.ORCID http://orcid.org/0000-0003-1093-4213
Rajeshwar P SinhaLaboratory of Photobiology and Molecular Microbiology, Department of Botany, Institute of Science, Banaras Hindu University, Varanasi, 221005, India. rpsinhabhu@gmail.com.ORCID http://orcid.org/0000-0002-0112-6161

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Phycocyanin (PC), a water-soluble pigment-protein complex, is well known for its wide range of biological functions. PC is composed of two polypeptide subunits, α and β, each covalently linked to linear tetrapyrrole chromophores (phycocyanobilins). These chromophores are responsible for its intense blue color and fluorescence properties, making PC an important marker in biochemical and biomedical research. This study provides comprehensive insight into the structural features and potent antioxidant (free radical scavenging) activity of PC extracted from the rice-field cyanobacterium Dolichospermum spiroides HKAR-23. The purification process involved successive steps of ammonium sulfate precipitation, dialysis, and ultracentrifugation, resulting in a pure (cosmetic grade) and stable pigment. This study further highlights the establishment of an effective and simplified protocol for purifying and recovering PC using sucrose-gradient ultracentrifugation. The characteristic spectral features of PC were confirmed using UV-VIS absorption spectrophotometry. Further structural and physicochemical characterization was performed using a range of analytical techniques, including nuclear magnetic resonance (NMR) spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX) analysis, and thermogravimetric analysis (TGA). The findings suggest that PC derived from Dolichospermum spiroides HKAR-23 exhibits a stable amorphous structure. The antioxidant potential of the purified PC was evaluated using DPPH, ABTS, SRSA, and FRAP assays, all of which revealed a strong, dose-dependent free radical scavenging activity. The IC50 values of PC were 83.2 µg mL− 1, 133.8 µg mL− 1, and 109 µg mL− 1 for the DPPH, ABTS, and SRSA assays, respectively. The high purity and preserved structural integrity of PC contributed to its potent antioxidant activity. These findings highlight PC as a promising natural bioactive compound with potential applications in the nutraceutical, pharmaceutical, and cosmetic industries.

Indexed as

CyanobacteriaFree Radical ScavengersPhycocyaninAntioxidantsBiphenyl CompoundsOryzaAntioxidantsBiphenyl CompoundsFree Radical ScavengersPhycocyaninAntioxidant activityCyanobacteriaPhycocyaninPurificationThermogravimetric analysis

Identifiers

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.