Phylogenic diversity of bacteria associated with potentially toxic cyanobacteria Microcystis aeruginosa: a synthesis on its bloom dynamics.

The occurrence of toxic bloom-forming cyanobacteria, Microcystis aeruginosa, has been frequently reported worldwide. These colony forming toxic cyanobacteria harbour a wide range of heterotrophic bacterial communities. The present study has attempted to understand the bloom dynamics of M.

Patterns and variability in the microplastic contamination along the southwest coast of India with emphasis on submarine groundwater discharge sites.

Beach sediments of the southwest coast of India were analysed to estimate the microplastic contamination with emphasis on the submarine groundwater discharge (SGD) zones. Both SGD and non-SGD sites were assessed for abundance, morphotype and polymer type of microplastics. Microplastic load was 230.

Observed evidence for the impact of coastal currents on the recurrent Noctiluca scintillans blooms in the northwest Indian Ocean coast.

Recently, South Eastern Arabian Sea (SEAS) experiences recurrent winter blooms of green Noctiluca scintillans with serious ecological consequences. Here, the analysis of green N. scintillans blooms in SEAS for the past three consecutive years (2018-2021) is presented.

Role of mesoscale eddies in the sustenance of high biological productivity in North Eastern Arabian Sea during the winter-spring transition period.

Convective mixing, mesoscale eddies and regenerated production sustain an above-average biological productivity in the North East Arabian Sea (NEAS) during the winter-spring transition period. Satellite-derived long-term data sets on Chlorophyll-a (Chl-a), Sea Surface Height Anomaly (SSHA), Sea Surface Temperature (SST) and Okubo-Weiss parameterization show existence of number of mesoscale eddies, propagating and non-propagating, that contribute to the regional production. The dominance of Eddy Kinetic Energy (EKE) over the Available Potential Energy (APE) in the core depth and the diameter (120km) of the observed eddy being wider than the Rossby Radius of Deformation (RRD, 55 km), it is suggested that the baroclinic instability is a possible mechanism for the eddy formation.

Sundarbanxylogranins A-E, five new limonoids from the Sundarban Mangrove, Xylocarpus granatum.

Five new limonoids, named sundarbanxylogranins A-E (1-5), were isolated from the seeds of an Indian mangrove, Xylocarpus granatum, collected from mangrove swamps of the Sundarbans, India. The structures of these limonoids were established by HRESIMS and NMR spectroscopic data. Sundarbanxylogranin A (1) is a rare limonoid containing a bicyclo[5.