Synthetic Studies - Literature review Example

? Synthetic studies towards the marine natural product cylindrospermopsin; the causative agent in freshwater toxic blooms Cylindrospermopsinin (C YN) is gradually being recognized as of the most global importance of the freshwater algal toxins. The rapid increase in CYN producers in temperate zones is yielding concern on the impact of this toxin to human, as well as environmental risk and health risks across the contents. Since 2000, there are several studies that have demonstrated the capacity for Cylindrospermopsin (CYN) to bio-accummulate especially in freshwater organism. This report synthesizes the current information on Cylindrospermopsin accumulation embracing information on the global distribution of Cylindrospermopsin (CYN) producers and summing-up of Cylindrospermopsin ecological and human effects. Studies carried out on bioaccumulation of Cylindrospermopsin are systematically reviewed collectively with analysis of accumulation patterns. A discussion pertaining aspects that influence bioaccumulation rates and potentials are outlined, together with detection, monitoring and risk assessments. Lastly, major gaps in the present research have been identified for future research. AREA OF STUDY This research, as well as others that have been carried out in this field seek to provided reliable information about the interconnection between cylindrospermopsin (a marine natural product) and its causative nature in freshwater toxic blooms, it anticipated to address a number of aspects such as properties of cylindrospermopsin, its distribution and detection, its impact on human health, ecological effects, patterns of toxic uptake and deposition among others. Previously, there have been several approaches used to address these aspects. This research sums up some of the descriptive data, together with information from previous studies, in an attempt to explain synthetic evidence towards the marine natural product (cylindrospermopsin) which is the causative agent in freshwater toxic blooms. It reviews as well, human health risk and environmental challenges associated with cylindrospermopsin. The study focus on Cylindrospermopsin is centered on human health risks and other environmental effects and still on bioaccumulation. This is regrettable given that Cylindrospermopsin is increasing in importance and bioaccumulation has significant impacts to human and ecological health risks (Humpage 2008). With no further research, synthetic risk assessments are roughly certain undervaluing the general risks of toxin-containing blooms. The study narrows down to effects of cylindrospermopsin in mammalian species, or their end organs and cells. It expands to toxicity model in order to show cylindrospermopsin impacts to invertebrates, bacteria, phytoplankton and protozoans as it seek to identify the substantial variability in toxicity of cylindrospermopsin in different animal models and animals of the same species. An outstanding summary of this research progress in connection to mechanism of toxicity of cylindrospermopsin . Generally, toxin exposure is characterized by delayed toxicity involving multiple organ systems mainly the kidney and liver. Toxicity is interceded by protein synthesis together with genotoxicity by DNA fragmentation. According to Weinreb (2001) it is clear that metabolic activation of cylindrospermopsin is connected to intense toxicity though the exact way on this remains oblique. Amusingly, it how cylindrospermopsin behaves, it also provides protection to exposed species (Eaglesham et al, 2001). Illustratively, cylindrospermopsin is unique to other algal toxins acting as causative agents to fresh waters toxin blooms being characterized by premature births, reduction in size and increase in mortality especially in mice pups. It is also a latent of endocrine INTRODUCTION Cylindrospermopsin (cyanobacteria, blue-green algae) are non-nucleated in nature and characterized as membrane – bound organelles without sexual reproduction but having an advanced ability to synthesize chlorophyII. The cylindrospermopsin are varied and adaptive group that inhabits a wide range of ordinary aquatic environments including severe habitats i.e. Antarctic ice shelves and volcanoes (Moore 1999). Nevertheless, they are components of phytoplankton habitants of freshwater, estuaries and marine surroundings. Of specific economic, human and environmental significance are those species of cylindrospermopsin recognized to form blooms, especially where these are connected with toxin production. Toxic blue-green blooms from marine and freshwaters are both recognized as severe human risks. The ability of cyanotoxins to cause serious health impacts has lifted them into consciousness of water managers globally. These health risks are caused as a result of activities such as swimming, drinking unsuitable treated water or taking of toxin-laden tissues mostly through ingestion from dietary supplements (Prociv 2002). In addition, cyanotoxins pose environmental health risks by exerting acute and chronic lethal and sublethal impacts to terrestrial and aquatic plants and animals. Indeed, bioaccumulation is different from environmental toxicity, although there is a direct relationship between toxin accumulation and strength of toxic effects. Bioaccumulation happens whenever the concentration in the tissue exceeds those present in the environment, and this can also result in toxin adsorption which permits the toxins to be linked with tissues of aquatic biota and biomagnifications, whereby toxin concentration are elevated via successive tropic level interactions (Bourke 1997). Most aquatic organisms face direct contact with aqueous toxins in water during algal bloom, majority of them are susceptible to ingestion of toxin laden cells through algal grazing or unintended drinking (Griffiths 2003). Hence, intake of any of the cyanotoxins is substantial. Recently, the ability for algal toxins to bioaccumulate has received much concern, specifically to accumulation in fish, or any other seafood species having either recreational or commercial significance However, most of have concentrated on hepatotoxin microcystin. Very minimal studies have been carried out on cytotoxin, cylindrospermopsin (CYN), in spite of its primarily extracellular availability which makes it specifically to be taken by a variety of aquatic organism. CONCLUSION In summary, changes in climate and pressure are likely to increase the range of cylindrospermopsin production especially in subtropical and temperate areas, most plants and animals will become vulnerable to cylindrospermopsin bioaccumulation and biomagnifications. Consequently, it will result in complementary human and ecosystem health implications. In spite of the progress in toxin detection in water, the predicament of detecting toxins that become fixed in tissues is still unsolved (Hawkins 1995). Moreover, in laboratory research, recovery and purification of cylindrospermopsin in spent culture media is still the most effective method to achieve quality toxin to work on. Though, there is commercially standardized cylindrospermopsin i.e. ELISA-based detection kits which are gradually being produced. Nevertheless, fewer laboratories are suppliers, hence future advancement of both resources maintains to be of high main concern (Hansen 1995). In this scenario, Radio-labeling of cylindrospermopsin would facilitate the research to indentify if the toxin can filter through all cell membranes and hence solve the predicament of detecting toxins that become fixed in tissues In this study, there is essence to emphasize application of environmental realistic tests concentrations’ in lab use. This report identifies that the maximum field concentration of cylindrospermopsin stand at 589 ug L, though previous studies had estimated it to be around 1.5mgL. However, in subtropical environs this figures fall below 20ug L. By comparison the two figures, cylindrospermopsin populace increase can be more at 2.6ug L. Thus further studies on synthesis of cylindrospermopsin ought to replicate this range of concentrations, as different to ecotoxicity tests whereby high nominal cylindrospermopsin concentrations have been applied (Weinreb 2001). The study has absolutely put in consideration intracellular cylindrospermopsin and hence it worth to note that treatment of water does not exclusively remove cylindrospermopsin Due to nonexistence of universal toxicity method that can identify each and every type of toxins, cyanobacteria supervision should involve MC and CYN tests. Conversely, in order to reduce costs, study for cylindrospermopsin should preferentially be carried out in the presence of anabaena and Aphanizomenon genera. Definitely, to determine this species is not a joke, Aphanizomenon flow-aquae is comparatively easy to be identified by shape that resembles its colony but this is not the case for Anabaena genus and other genus in this group that have solitary species filaments (Humpage 2008). Nevertheless, the difference between anabaena and Aphanizomenon is censured since the equivalent phenotypes for a particular class justify the presence of only one genus. Existence of cylindrospermopsin in water bodies underpins the necessity to outlaw copper sulfate in tank s holding drinking water as a reserve of degradation of soluble cylindrospermopsin. In view of the fact that cylindrospermopsin is plentiful in the extracellular fraction and that it can withstand in water for several days without change in its setting it calls for high measures to monitor cylindrospermopsin in water. Also the availability of both MC and CYN simultaneously in water confirms why we need to manage reserves for drinking water and other recreational services (Eaglesham et al, 2001). Generally, it is important to comprehend the mechanism of cylindrospermopsin excretion and the likely influence of environmental conditions on its production. 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