Large amount of lignocellulosic waste are generated through forestry and agricultural practices, which pose environmental pollution and can be converted into various different 'value added' products. Bioconversion of lignocellulosic waste by marine cyanobacteria could make a significant contribution to the production of organic chemicals. Cyanobacteria which are phototrophs and show high flexibility to varied environment because of their trophic independence to carbon and even nitrogen in a number of cases and play potential role in biodegradation. Thus biodegradation of P. juliflora using marine cyanobacterium O. laetevirens, result in release of phenolic compounds which were detected using phenol estimation followed by spectral analysis, TLC, HPLC,GC-MS and FTIR. The results clearly showed the presence of catechin like compound without any noticeable impurities in the extract of degraded P. juliflora when compared with control P. juliflora alone.