Role of trace element of the growth and Physiology of selected microalgae

The main objective of the study is primarily to determine the magnitude of selected trace elements, the concentrations of which would possibly accelerate growth resulting in larger biomass and sustained period of exponential phase for economically viable harvest. The study on the effect of three trace elements namely Cu, Mn and Zn on two species of algae,ISOChrySiS galbana Parke and Synechocystib salina Wislouch under different conditions of salinity, PH and temperature involves several combinations for each metal, from which the relative set of conditions has been adduced. The scheme of the experiments was statistically designed for interpretation of data and factors were assessed and graded according to relative importance. The methodology adopted for data interpretation is analysis of variance by split-plot design method. The thesis has been divided into five chapters. The introductory chapter explains the relevance of the research work undertaken. Chapter 11 gives a review on the work pertaining to the above mentioned three trace elements in relation to nutrition as well as on the toxic aspects about which there is an abundance of literature. Chapter Ill presents a detailed description of the material and specialised methods followed for the study. The results and conclusions of the various experiments on effect of metals on growth and other physiological activities are discussed in Chapters IV and V.

Coastal and ground water pollution in Kavaratti island, Lakshadweep sea

The tiniest Union territory of India, Lakshadweep, is an archipelago, with an area of 32 Sq. km. consisting of 12 atolls, three reefs and five submerged banks, lies between 8° and 12°30'N latitudes and 71° and 74" E longitudes. It is one of the most important and critical territories of India from economic and defence point of view. Specialised environment having typical geological set up, Lakshadweep is ecologically sensitive to even slight climatic or anthropogenic interference. Pollution of coastal seas, over exploitation and contamination of the fresh water sources are thus become great concerns to the existence of the island. Typical geological set up and interference cause threat to the ecology of the fragile environment and resources of the island as well as its resources. Marine pollution and ground water contamination are concerns in this regard. Even though attentions were made to assess the physico—chemical and bacteriological status of the marine and groundwater systems separately, an integrated approach has not been evolved. The present study with its broad objectives is attempted for an integrated assessment of microbiological, physicochemical and biological characteristics of the surrounding seawater and microbiological and physico—chemical characteristics of the ground water in Kavaratti island. The entire study has been organised in 4 chapters

Glycogen degrading enzymes and their regulation in benthic animals and estuarine fish

Alpha glucan phosphorylase plays a very significant role in glycolysis. The inhibition and activation of this enzyme have significant effect on the rate of glycolysis. The rate of glycolysis is also determined by the interconversion between the active 3 and inactive Q forms of phosphorylase by two specific enzymes called phosphorylase phosphatase and phosphorylase kinase. The allosteric properties and interconversion mechanism reported for well—studied animal muscle phosphorylases do not fall under a general pattern. Studies using purified phosphorylase from marine sources are scanty. Detailed studies using specialised tissues from more marine animals are necessary to find the factors that control the properties and activities of the enzyme. This thesis is an attempt in this direction. The thesis deals with a detailed study of the control of the phosphorylase by both allosterism and interconversion between the g and b forms from four different aquatic animals of different habitat. Phosphorylase frm the four different animal muscles were purified either partially or completely and the kinetic and control properties were studied.

Studies On The Reproduction Of Indian Whiting Sill/160 5'/Ham/1 (Forskal) (Percoidei, Sillaginidae)

From the point of view of rational exploitation and proper management of the fishery resources as well as for the development of intensive aquaculture of fishes through selective breeding, brood stock development, domestication and genetic improvement, a sound knowledge of reproductive biology and physiology of the candidate species is of great importance. In recent times, a wealth of information on maturity, spawning habits, spawning periodicity, spawning season, size at maturity and fecundity of commercially important fishes has been generated. Gametogenesis involves the transformation of Primordial germ cells in the gonads into specialised cells or gametes, namely ova in the female and sperms in male, through a series of complex morphological and cytological events. The formation of male gamete is known as spermatogenesis. In the female, the primary growth phase involving the formation of primary oocyte from oogonia is known as oogenesis, which would be followed by the secondary growth phase, in which considerable increase in the size of the oocyte occurs, due mainly to accumulation of yolk. This process is known as vitellogenesis, which would be followed by final maturation and ovulation of the ova. In the present work, basic aspects of maturation and spawning, salient features of gametogenesis and associated biochemical changes occurring during these processes in an important cultivable fish, Sillago sihama belonging to the family Sillaginidae have been investigated.

Bioactive Metabolites and Biomarkers from Rhizophoraceae mangroves- A Chemotaxonomic Approach

Mangroves are specialised ecosystems developed along estuarine sea coasts and river mouths in tropical and subtropical regions of the world, mainly in the intertidal zone. Hence, the ecosystem and its biological components is under the influence of both marine and freshwater conditions and has developed a set of physiological adaptations to overcome problems of anoxia, salinity and frequent tidal inundations. This has led to the assemblage of a wide variety of plant and animal species of special adaptations suited to the ecosystem. The path of photosynthesis in mangroves is different from other glycophytes. There are modifications or alterations in other physiological processes such as carbohydrate metabolism or polyphenol synthesis. As they survive under extreme conditions of salinity, temperature, tides and anoxic soil conditions they may have chemical compounds, which protect them from these destructive elements. Mangroves are necessarily tolerant of high salt levels and have mechanisms to take up water despite strong osmotic potentials. Some also take up salts, but excrete them through specialised glands in the leaves. Others transfer salts into senescent leaves or store them in the bark or the wood. Still others simply become increasingly conservative in their water use as water salinity increases. A usual transportation or biosynthetic path as other plants cannot be expected in mangrove plants. In India, the states like West Bengal, Orissa, Andhra Pradesh, Tamil Nadu, Andaman and Nicobar Islands, Kerala, Goa, Maharashtra, and Gujarat occupy vast area of mangroves. Kerala has only 6 km2 total mangrove area with Rhizophora apiculata, Rhizophora mucronata, Bruguiera gymnorrhiza, Bruguiera cylindrica, Avicennia officinalis, Sonneratia caseolaris, Sonneratia apetala and Kandelia candal, as the important species present, most of which belong to the family Rhizophoraceae.Rhizophoraceae mangroves are ranked as “major elements of mangroves” as they give the real shape of this unique and interesting ecosystem and these mangrove species most productive and typical characteristic ecosystem of World renowned. It was found that the Rhizophoraceae mangrove extracts exhibit several bioactive properties. Various parts of these mangroves are used in ethnomedicinal practices. Even though extracts from these mangroves possess therapeutic activity against humans, animal and plant pathogens, the specific metabolites responsible for these bioactivities remains to be elucidated. Various parts of these mangroves are used in ethnomedicinal practices. There is a gap of information towards the chemistry of Rhizophoraceae mangroves from Kerala. Thorough phytochemical investigation can achieve the validity of ethnomedicines as well as apply the use of mangrove plants in the development of new drugs. Such studies can pave a firm base for their use in biomarker and chemotaxonomic studies as well as for the better management of the existing mangrove ecosystem. In this study, the various chemical parameters including minerals, biochemical components, bioactive and biomarker molecules were used to classify and assess the possible potentials of the mangrove plants of the true mangrove family Rhizophoraceae from Kochi.

Biomarker Geochemistry of Core Sediments in the Mangrove Ecosystems along Northern Kerala Coast

Mangroves are diverse group of trees, palms, shrubs, and ferns that share a common ability to live in waterlogged saline soils exposed to regular flooding, and are highly specialised plants which have developed unusual adaptations to the unique environmental conditions. They are sites of accumulation and preservation of both allochthonous and autochthonous organic matter owing to their strategic loction at the interface between land and sea and prevailing reducing environment. They are among the most productive ecosystems and are efficient carbon sinks with most of the carbon stored in sediments.Mangrove ecosystems play a significant role in global carbon cycle and hence the knowledge on the processes controlling the delivery of organic matter to coastal sediments, and how these signatures are preserved in the sediment is a prerequisite for the understanding of biogeochemical cycles. The evaluation of nature and sources of organic matter can be accomplished by the determination of biochemical constituents like carbohydrates, proteins and lipids. When characterised at molecular level, lipids provide valuable information about the sources of organic matter, even though they account only small fraction of organic matter. They are useful for the paleo-environmental reconstruction because of their low reactivity, high preservation potential and high source specificity relative to other organic class of compounds. The application of recent analytical techniques has produced a wealth of useful information but has also indicated the gaps in our knowledge on cycling of organic matter in the coastal ecosystems. The quantity and quality of organic matter preserved in sediments vary depending up on the nature of material delivered to the sediment and on the depositional environment. The input from both autochthonous and allochthonous sources sharpens the complexity of biogeochemistry of mangrove ecosystem and hence bulk sedimentary parameters are not completely successful in evaluating the sources of organic matter in mangrove sediments. An effective tool for the source characterisation of organic matter in coastal ecosystems is biomarker approach. Biomarkers are chemical "signatures" present in environmental samples whose structural information can be linked to its biological precursor. The usefulness of molecular biomarkers depends on high taxonomic specificity, potential for preservation, recalcitrant against geochemical changes, easily analysable in environmental samples and should have a limited number of well-defined sources.