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Macrobenthic community being used as marine health indictor vis-à-vis to anthropogenic disturbance since their characteristic of life cycle (reproductive mode, sedentary, energy transfer, sensitive-resistance species, indicator organism etc.). Therefore, the present study was chosen in Vizag port waters have been subject to a variety of anthropogenic pressure in the last two decades. The purpose of this study was to assess the ecological status of the port environment through biotic indices like AZTI 's Marine Biotic Index (AMBI) and Multivariate-AMBI Index (M-AMBI) which have been successfully validated geographically and anthropogenically stressed habitats. The result revealed that the inner harbor (IHC, Iron ore Q1 & Iron ore Q7) stations are heavily disturbed while the outer harbor fall between undisturbed and moderately disturbed status. It was observed that the reduced tidal action inside the harbor determines the health status indicating that the Iron ore transporting areas are at high risk with respect to benthic population.

The ubiquity and high bioavailability of microplastics have an unknown risk on the marine environment. Biomonitoring should be used to investigate biotic impacts of microplastic exposure. While many studies have used mussels as indicators for marine microplastic pollution, a robust and clear justification for their selection as indicator species is still lacking. Here, we review published literature from field investigations and laboratory experiments on microplastics in mussels and critically discuss the suitability and challenges of mussels as bioindicator for microplastic pollution. Mussels are suitable bioindicator for microplastic pollution because of their wide distribution, vital ecological niches, susceptibility to microplastic uptake and close connection with marine predators and human health. Field investigations highlight a wide occurrence of microplastics in mussels from all over the world, yet their abundance varies enormously. Problematically, these studies are not comparable due to the lack of a standardized approach, as well as temporal and spatial variability. Interestingly, microplastic abundance in field-collected mussels is closely related to human activity, and there is evidence for a positive and quantitative correlation between microplastics in mussels and surrounding waters. Laboratory studies collectively demonstrate that mussels may be good model organisms in revealing microplastic uptake, accumulation and toxicity. Consequently, we propose the use of mussels as target species to monitor microplastics and call for a uniform, efficient and economical approach that is suitable for a future large-scale monitoring program.

Objective: To isolate and characterize the antibacterial compounds from starfish Stellaster equestris (S. equestris). Methods: The starfish S. equestris was collected from Mudasalodai, southeast coast of India. The whole body was extracted with high polar and medium polar solvents such as methanol and ethanol. The antibacterial activity has been tested against human bacterial pathogens using standard disc diffusion method. Results: The present investigation exhibited that the crude methanol extract showed the maximum zone inhibition [(9.7±0.3) mm] against Escherichia coli (E. coli) and Vibrio parahaemolyticus at 100% concentration and minimum was Staphylococcus aureus [(4.0±0.6) mm]. The crude ethanol extract showed maximum zone of inhibition in E. coli [(9.70±0.33) mm] and the lowest concentration exhibited the minimum inhibition activity against all bacterial pathogens. The fractions showed the maximum inhibition zone in Klebsiella oxytoca (5.00±0.82 mm), Salmonella typhi (S. typhi) (5.00±0.82) and Staphylococcus aureus [(3.0±2.3) mm]. One way ANOVA analysis of antibacterial activity showed no significant difference at 0.05% level (P>0.05). The crude ethanol extract showed the minimum inhibitory concentration against E. coli (100%), Klebsiella pneumoniae (75%), S. typhi (100%) and Vibrio cholerae (100%). The fraction exhibited the minimum inhibitory concentration against Klebsiella pneumonia, Proteus mirabilis, S. typhi, Staphylococcus aureus and Vibrio cholerae at 100% whereas E. coli was at 75% concentration. No bacterial growth was observed against Klebsiella oxytoca at 100% concentration. Conclusions: The result of the present study indicates that the crude and fractions of starfish S. equestris have remarkable antimicrobial activities against human bacterial pathogens. Further fraction has been characterised by using GC-MS and 1 H and 13 NMR spectroscopy analysis.