Effect of heavy metal pollution on growth, carotenoid content and bacterial flora in the gut of Perna viridis (L.) in in situ condition

The soft tissue of females of Perna viridis showed highest concentration of Fe, Mn, Cu, Zn, Cd, Pb, Co, Ni and Hg followed by males and indeterminates . The Hg was not detected in different sexes during May. The biomagnificati on of all heavy metals was maximum in gonad. In general, the order of metal accumulation in the soft tissue of Perna viridis was Fe > Co > Zn > Ph > N i > Cu > Mn > Cd > Hg. The definite correlation between biomagnification of different heavy metals in whole animal or its different organs could not b e observed with that of their concentrations in sediment. However, the conc entration of all heavy metals was higher in soft tissue or its different or gans than sea water. The concentration of total carotenoids and unsaponifia ble carotenoid were higher in females followed by males and indeterminates. Both types of carotenoids in gonads had higher concentration than other bo dy organs. In general, the total count of pathogenic bacteria was maximum i n the gut of females followed by indeterminates and males. The percentage r eduction of pathogenic bacteria after five days of starvation ranged from 2 8.92 to 42.81 in the least reduction category to 61.59 to 75.25 for the hig hest reduction category.