East Coast Of Tamil Nadu Research Articles

Integrating frequency and duration in flood susceptibility assessment: a novel approach for the east coast of Tamil Nadu, India

Integrating frequency and duration in flood susceptibility assessment: a novel approach for the east coast of Tamil Nadu, India

Distribution, ecological risk assessment, and source identification of potential toxic elements (PTEs) in Muttukadu backwater sediments, Southern India

Muttukadu Backwater is a robust estuary on the east coast of Tamil Nadu is contaminated by industrial, residential, and tourism-related activity (especially boat houses). In this present research, we investigated the heavy metal pollution, spatial distribution and statistical analysis of muttukadu coastal sediments, east coast of the Bay of Bengal in south India. In this study, we present the distribution of heavy metals in backwater sediments reveals enhanced levels of Fe, Mn, Cr, Zn, Cu, Ni, Pb, and Co and the highest concentrations of these metals are found at stations 2, 4, and 8. Based on contamination indices such as CD, Igeo, and PLI, moderate contamination is clear evident. However, the present data of Cr, Cu, and Pb metals have indicated low to moderate anthropogenic influence. We have identified the metals of Cr, Cu, and Pb indicated the High habitat risks are highlighted by ecological risk assessments, and it is due to the anthropogenic factors. Cu, Mn, Zn, and Cr are sourced from anthropogenic sources, while Pb, As, Co, and Ni originate from natural sources, according to spatial distribution analysis. A significant disturbance to the aquatic environment is caused by human activity. In this present study, underscores the necessity of pre-flooded dataset for future comparative research and ecological conservation in Muttukadu Backwater and their environments.

Extended Spectrum Beta Lactamase Profile of Citrobacter Species Isolated from Various Samples in the North East Coast of Tamil Nadu, India: A Cross-sectional Study

Introduction: Citrobacter species play a significant role in causing hospital-acquired infections, especially those affecting the urinary and respiratory systems, and they are commonly present in faeces. Healthcare systems are facing a major challenge due to the rise of antibiotic-resistant Gram-negative infections resistant to antibiotics. Aim: To identify the genotypic characterisation of the resistant gene blaTEM-1 in Citrobacter spp. obtained from a range of clinical samples. This investigation seeks to provide insights into the patterns of antibiotic resistance exhibited by these bacteria. Materials and Methods: This cross-sectional study was conducted between August 2021 and February 2022. Preliminary examinations included screening as well as confirmatory tests for Extended Spectrum Beta Lactamase (ESBL) production, which were confirmed by the combination disk method and double disc synergy test. Genotypic detection of the blaTEM-1 gene was done using the Polymerase Chain Reaction (PCR) technique. Demographic parameters like gender and age were assessed. Statistical analysis was done using the Statistical Package for the Social Sciences (SPSS) Software version 21.0. Results: Citrobacter koseri (66 isolates, 54.5%) was found to be the predominant species among the Citrobacter spp., followed by Citrobacter freundii (55 isolates, 45.5%). Urine samples were the primary source of Citrobacter spp. isolates, comprising 52 isolates (43%) of the total. In this study, the prevalence of ESBL producers was reported to be 49 isolates (77.8%) identified as ESBL producers. Tigecycline demonstrated a 100% effectiveness rate, followed by Piperacillin-Tazobactam (96% sensitivity) and Amikacin (95% sensitivity). Out of the 20 Citrobacter spp. isolates that tested positive for ESBL, 15 isolates (75%) were found to be positive for blaTEM-1. Conclusion: The results of this study provide insight into the changing patterns of antibiotic resistance in Citrobacter spp., with particular emphasis on ESBL profiles. Thus, it is imperative to implement intervention techniques to reduce the ongoing selection and spread of these more resistant bacteria, as well as efficient infection-control measures to manage epidemics. These results advance the comprehension of antibiotic resistance patterns and guide initiatives to combat the increasing threat of antibiotic resistance.

Temporal evolution of shoreline changes from 1972 to 2020 along the coast between Pondicherry and Point Calimere, East Coast of Tamil Nadu, India

The aim of this study was to estimate the changes in shoreline evolution that have occurred between 1972 and 2020. The intervals of analysis were 1980, 1991, 2000, 2005, and 2020. The findings suggest that there were hotspots of erosion along the coasts of Gunduppalavadi, Thandavarayan, Kattur, and Rajamadam, while there was accretion along Cuddalore, Kothattai, Pudupattinam, and the eastern parts of Thiruppoondi. The study highlights that most of the regions from Portonova to Point Calimere are at risk from a sea level rise of 2 m, and almost all the coastal stretches are at risk from a sea level rise of 2 to 5 m. The results of the study show that the shoreline changes from 1972 to 2020 were estimated and represented as 29.84% stable, 66.74% as accretion, and 3.45% as erosion during 1980. For 1991, the nature of the coast shared 69.66% accretion and 30.34% stability. In 2000, the coast represented 35.73% stability, 62.76% accretion, and 1.51% erosion. The findings suggest that the behavioral change on the coast during 2005 was 54.80% stable, 19.31% accretion, and 25.90% erosion. In 2020, the percentage of stable, accretion, and erosion represented 56.76%, 28.88%, and 14.37%, respectively. The study provides important insights into the changes in shoreline evolution that have occurred over time and the potential risks associated with sea level rise.

Biological Control of sheath blight disease in rice using Marine Actinomycetes (Streptomycetes rochei) AMET A311 strain

The soil samples were taken from the rhizome soil of coastal sand dune plants along the Hare islands, Tuticorin, East Coast of Tamil Nadu, in order to isolate an efficient antifungal marine actinomycetes. A total of 70 actinomycetes were isolated from the samples collected. Based on colony morphology, aerial mass color, melanoid pigments, reverse side pigments, soluble pigments, spore chain morphology and spore surface, 62 of the 70 isolates were identified as distinct. Fifty isolates from the 62 distinct colony were chosen for the antifungal activity based on their capacity to endure salt concentrations over 1M. Rhizoctonia solani, a fungus pathogen, was tested against each of the 50 identified strains. Rhizoctonia solani, a fungus, was resistant to about 36% of the isolates. AMET 307, AMET 308 and AMET 307, AMET 311 and AMET 315 exhibited the highest level of antifungal activity against Rhizoctonia solani. Using 16s rRNA sequencing, this effective antifungal strain was further identified as the Streptomycetes rochei AMET 311 strain (KT334600).

SEASONAL VARIATION IN SELECTED HEAVY METAL CONCENTRATIONS IN THE NANDALAR ESTUARY EAST COAST OF TAMIL NADU-INDIA

Estuaries are dynamic environments with respect to metal speciation, as many of the physicochemical parameters that affect metal equilibria are subject to change as fresh and marine waters mix. pH, hardness, dissolved organic matter concentration, and ionic strength will all significantly affect the partitioning of copper within and between solid and solution phases. Heavy metals have been present in nature for many years, but their toxicity is increasing as a result of anthropogenic activities. There is an increase in heavy metal contamination in many inland waters as well as estuarine ecosystems nowadays. The aim of the present study is to evaluate seasonal variation in some selected heavy metal concentrations in the Nandalar estuary on the east coast of Tamil Nadu, India, during the 2020 to 2021 period. The monsoon season saw the highest appearance of followed the order of Cu (0.043mg/L) > Cr (0.027mg/L) > Zn (0.024mg/L) > Pb (0.023mg/L) > Ni (0.012mg/L) > Cd (0.007mg/L) > Hg (>0.00001mg/L) metals compared with the pre and post monsoon seasons, while present metals were higher than the Fisheries and aquatic life standard reference value. Overall, the metal of Cu (0.032 to 0.043 mg/L) was the higher concentration found to be in the Nandalar estuary. The seasonal variation analysis showed to higher content of copper was observed in Nandalar estuary, Tamil Nadu.

Diversity of mollusca in selected coastal wetlands of Nagapattinam district in the East Coast of Tamil Nadu, Southern India

Diversity of mollusca in selected coastal wetlands of Nagapattinam district in the East Coast of Tamil Nadu, Southern India

Ancient Anchors showing Maritime History (Based on Tamil University Museum Evidence)

Anchors made of stone, wood or metal played a significant role in marine history. They have been used as protection material for ships in ports and as a means of establishing maritime relations with other countries. A variety of anchors used in passenger ships, cargo ships, and warships around the world have been discovered by marine researchers. Stone anchors were initially introduced in India and iron anchors after the arrival of the Europeans. Since then iron anchors have been developed and used in various parts of India. Ancient stone anchors and later iron anchors have been found especially on the east coast of Tamil Nadu. Such anchors are a testament to man’s maritime ability and knowledge in ancient times. Such anchors are on display at the Tamil University Museum, Thanjavur. In that sense this article describes the maritime technique and maritime history that the Tamils knew for commercial purposes in ancient times.

Assessment of Seasonal Variation (2020 to 2021) in Physico-Chemical Parameters of Nandalar Estuary in East Coast of Tamil Nadu, India

Estuaries are defined as the areas between rivers and the ocean that have unique ecological characteristics, a wealth of flora and fauna, and are essential to both biodiversity and hydrological processes. Aquatic ecosystems depend on their biological traits as well as their physical and chemical qualities. The objective of the current study was to identify seasonal variations in the physico-chemical parameters of Tamil Nadu's Nandalar Estuary. The physico-chemical characteristics of the Nandalar Estuary were recorded which have an impact on the estuarine environment. Future analyses of the ecological, biological, and cultural elements of estuarine species as well as the allowable limit of fisheries and aquatic life would benefit from preliminary data on the physico-chemical parameters in this Nandalar estuary area.

Human health risk assessment for fluoride and nitrate contamination in the groundwater: a case study from the east coast of Tamil Nadu and Puducherry, India

Human health risk assessment for fluoride and nitrate contamination in the groundwater: a case study from the east coast of Tamil Nadu and Puducherry, India

Impact of hydrogeochemical processes and its evolution in controlling groundwater chemistry along the east coast of Tamil Nadu and Puducherry, India.

The present study area falls beside the coastal zone of Tamil Nadu, and Puducherry is characterized by varied geological formations that mostly contain groundwater resources that are primarily utilized for domestic, agricultural, industrial, and other utilities. The study aims to differentiate various hydrogeochemical processes responsible for disparities in water chemistry. Groundwater samples were collected from 66 sites during the two major seasons: pre-monsoon and post-monsoon. The analytical data were separated into terrain vice and utilized for preparing graphical plots as well as mathematical calculations to obtain the existing relationship among chemical constituents and water quality. The Ca-HCO3, Na-Cl, Ca-Na-HCO3, mixed Ca-Mg-Cl, Ca-Cl, and Na-HCO3 are the main hydrochemical facies observed from the groundwater samples. The ionic relationship among the samples indicates the control of direct and reverse ion exchange in the concentration of Ca2+, Mg2+, Na+, and K+ in groundwater. Moreover, silicate weathering contributes more in comparison with carbonate and evaporite dissolution. Gibbs plots reveal that water-rock interaction and evaporation processes are the main mechanisms controlling the water chemistry. The saturation index of different mineral phases indicates groundwater to be oversaturated with silicate mineral phases irrespective of the terrain. Statistical methods like correlation and principal component analysis were also performed to differentiate the specific association and possible source of the dissolved constituent in the groundwater. The study concludes the influence of multiple processes such as silicate weathering, direct and reverse ion exchange, secondary dissolution, saline water intrusion, and anthropogenic sources as the main reasons responsible for variation in groundwater chemistry.

Assessment of heavy metals and radionuclides (238U, 232Th and 40K) concentration of beach sands collected from East Coast of Tamilnadu, India with multivariate statistical approach

ABSTRACT This paper discusses the relation between the heavy metal and radionuclide activity concentration in beach sand samples collected from East Coast of Tamilnadu. The elemental composition in beach sands is determined by EDXRF technique. The mean concentrations of elements followed in the order of Si > Ca > Fe > Al > Mg > K > Ti > Mn > Zr > Sr > Zn > Pb > Ni > Cu > Cd > Co in the study area. A NaI(Tl) gamma-ray spectrometer has been used to determine activity concentration of 238U, 232Th and 40K in sand samples. The measured activity in the sand samples ranged from 3.0 to 1766.8 Bqkg−1, 3.0 to 8326.88 Bqkg−1 and 11 to 1434.9 Bqkg−1 for 238U, 232Th and 40K, respectively. The measured natural radioactivity concentration was compared with worldwide average values as reported by UNSCEAR. The interrelation between the natural radioactivity and heavy metal concentration is determined using Pearson correlation coefficient, factor and cluster analysis for finding existing relation between them. The results showed that there is a significant relation of heavy metals for heavy minerals which can contribute radioactivity concentration based on the correlation and factor analysis.

Spatial and heavy metal assessment in beach sands of east coast of Tamil Nadu, India

Beach sand samples were collected from the East Coast of Tamil Nadu and the concentration of major and trace elements in them were determined using the Energy-dispersive X-ray Fluorescence (EDXRF) technique. The concentration of elements such as Mg, Al, Si, K, Ca, Ti, Fe, Cr, Mn, Co, Ni, Cu, Zn, Pb, Cd, Zr & Sr was determined to assess the contamination status and the degree of pollution level. The abundance of elements in the samples was found to occur in the order: Si > Ca > Fe > Al > Mg > K > Ti > Mn > Zr > Sr > Zn > Pb > Ni > Cd > Cu > Co. The mean concentration of the elements in the beach sand was compared with those in the Earth's Crust, Sandstones, and Ultrabasic Rocks to see if there were any anomalies. The assessment of pollution was carried out by computing the Enrichment factor (EF). The enrichment factor of Fe & Mn indicates that they are possibly from the anthropogenic sources. XRD analysis was carried out to study the influence of heavy metals in the sand samples collected from the study area. SEM-EDX analysis was utilized to reveal the morphology and elemental composition of the selected sand samples. The distribution of metal concentration in the study area was identified by plotting the spatial map. The inter-relationship between the elements was analyzed using the Pearson Correlation Matrix to differentiate between the origin of metals namely anthropogenic or geogenic sources.

Antioxidant status of selected sea weeds of Manamelkudi coast, Pudukkottai district

Manamelkudi, located along the Palk Strait of East coast of Tamil Nadu serve as treasure houses for valuable marine resources like sea grass and sea weeds. A study was undertaken at Agricultural College & Research Institute, Kudumiyanmalai during 2016-17 to evaluate the nutritional composition of the seaweeds in order to use them as potential food ingredients. Sea weed samples were collected from Manamelkudi village of Pudukkotai district and were identified as Gracilaria salicornia (C.Agardh) Dawson and Gracilaria edulis (S.G. Gmel.) P.C. Silva Gracilariaceae at Botanical Survey of India, Coimbatore. The samples were washed in sea and fresh water to remove associated organisms and other extraneous matters. The sea weeds were dried, powdered and used for assessing the antioxidant status. G. edulis showed higher activities of enzymic antioxidants superoxide dismutase (312.03 U/g) and catalase (50.1U/g) when compared to G. salicornia (SOD:266.27U/g and CAT:37.1U/g). Maximum levels of the non-enzymic antioxidants, (total phenol and flavonoid) was found in G. edulis when compared to G. salicornia (5.8 and 3.43mg/g; 5.23 and 3.3mg/g respectively). The extent of lipid peroxidation assessed revealed 70.5 and 32.1 percent inhibition by the ethanolic extract of G. edulis and G. salicornia respectively. The results were comparable with that of the standard antioxidant BHT. Phytochemical analysis revealed the presence of alkaloids, carbohydrates, saponins, proteins, aminoacids, phytosterols, phenolic compounds, flavonoids, terpenoids and tannins except saponins and terpenoids in G. salicornia. Thus it can be concluded from the present investigation that both the seaweeds are potentially rich in natural antioxidants and could be used as nutrient supplements in food industry.

Evaluation of Phytochemicals in Methanolic Extract of Hypnea musciformis (Wulf.) Lamouroux Collected from Manapad in the South East Coast of Tamil Nadu, India

The present study was carried out to evaluate the phytochemicals in the methanolic extract of Hypnea musciformis (Wulf.) Lamouroux collected from Manapad in the south east coast of Tamil Nadu, India. The phytochemical screening of methanolic extract was studied using the standard procedure by UV-Visible spectroscopic, HPLC and FTIR. The UV-Visible spectrum showed the compounds separated at the nm of 300, 350, 420, 460, 534.5, 538.5, 606.35 646 and 667.5 with the absorption 0.361, 0.249, 0.675, 4.000, 0.967, 0.098, 1.260, 2.460 and 2.571 respectively. The qualitative HPLC fingerprint profile displayed six compounds at different retention time of 1.923min, 2.140min, 2.533min, 3.017min, 3.260min and 3.525min. The result of FTIR analysis was found the presence of functional groups such as amides, phosphorus compound, alcohols, phenols and halogen compounds. Keywords: Phytochemicals, Hypnea musciformis, UV-Visible, HPLC, FTIR

Effects of physicochemical properties on heavy metal, magnetic susceptibility and natural radionuclides with statistical approach in the Chennai coastal sediment of east coast of Tamilnadu, India

The aim of the study was to determine the effects of physicochemical properties of sediment samples on the heavy metal, magnetic susceptibility, and natural radioactivity concentration. Spectroscopic techniques like energy-dispersive X-ray fluorescence, dual-frequency susceptibility meter, and gamma ray spectrometry measurements are commonly employed for the determination of heavy metals, magnetic particle, and radioactivity concentration in sediment sample collected from Pulicat Lake to Vadanemmeli, of Chennai Coast, Tamilnadu. The relations between the physical and chemical properties and studied parameters of sediment samples were mainly clarified with Pearson correlation, factor, and cluster analysis. Silt content was the most effective parameter on the studied parameter. The results are discussed and the conclusion is drawn.

The antioxidative effects of bioactive products from Sargassum polycystum C. Agardh and Sargassum duplicatum J. Agardh against inflammation and other pathological issues

The present study was aimed to determine the phenol, total flavonoids and antioxidant potentials of Sargassum polycystum C. Agardh and Sargassum duplicatum J. Agardh from south east coast of Tamil Nadu and India using DPPH, phophomolybdenum and hydrogen peroxide scavenging activity. The total phenols, total flavonoids and antioxidant activities of S. polycystum and S. duplicatum were determined. Highest phenols (33.49 and 149.52 mg GAE/g) were observed in chloroform extracts of S. polycystum and methanolic extracts of S. duplicatum. The acetone extracts of S. polycystumand S. duplicatum demonstrated maximum amount of flavonoids compared to other studied extracts. Maximum amount of phosphomolybdenum reduction was observed in acetone extracts of S. polycystum and methanolic extracts of S. duplicatum. The DPPH radical scavenging activity of different extracts of S. polycystum and S. duplicatum were as follows acetone > chloroform > Petroleum ether > methanol and acetone > chloroform > methanol >Petroleum ether respectively. The H2O2 scavenging activity of S. polycystum extracts were as follows Petroleum ether extracts of S. polycystum (67.9%) > acetone (67.3%) > chloroform (58.6%) > methanol (51.78%). Acetone extracts of S. duplicatum showed maximum inhibition (90.39%) followed by petroleum ether, chloroform and methanolic extracts (75.11, 72.37 and 54.59%) respectively. The present study results confirmed the antioxidant properties of the two selected brown seaweeds viz., S. polycytum and S. duplicatum. The total phenols, flavonoids and alkaloids may be responsible for the antioxidant activities.

Natural radioactivity concentrations and dose assessment in coastal sediments along the East Coast of Tamilnadu, India with statistical approach

The present study was conducted to determine the activity concentration of 238U, 232Th and 40K in coastal sediments samples from Poombuhar to Karaikal along East coast of Tamilnadu, India using gamma ray spectrometry. The average activity concentration for 238U, 232Th and 40K were obtained as 36.82 (Bq kg−1), 50.11(Bq kg−1) and 320.38 (Bq kg−1), respectively. These obtained results were used to calculate the radiological hazard parameters like radium equivalent activity (Raeq), absorbed gamma dose rate (DR), the annual effective dose equivalent (AEDE), Annual gonadal dose equivalent (AGDE), Activity utilization index (AUI), External hazard index (Hex), Internal hazard index (Hin), Gamma representative level index (RLI) and Excess lifetime cancer risk (ELCR). The computed radiological parameters values are compared with the internationally approved recommended values. The multivariate statistical method is used to simplify and organize large data sets to indicate natural associations between samples and variables.

Analysis of mtCOI and 18S rRNA Sequence-Based Characterization of Recently Commercialized Marine Edible Pufferfishes

The pufferfishes are considered as a serious hazard to consumers since it contains a strong marine toxin which can be lethal to human beings. However, some species of the pufferfishes have commercial value in the food industry and in the aquarium trade. Hence, the identification of pufferfishes plays a major role to find out their type. Analysis of genetic materials is the constitutional source of rapid and accurate species identification method to reveal even intra-specific difference of their phenotypic plasticity when morphological distinctiveness fails to provide intact information. In the present study, twenty marine pufferfish specimens belonging to five different commercially important species were collected from April 2016 to May 2017 from Mandapam region, east coast of Tamil Nadu. Consensus primers of two different genes (mtCOI and 18S rRNA) were employed to compare the genetic variations. Results suggest that the species within the taxa were accurately identified by mtCOI gene when compared to the 18S rRNA gene. Further, the computational analytical tools such as multiple sequence alignment, genetic distance analysis, phylogenetic analysis and motifs were used to study the genetic variation between the species. This investigation recommends the accurate identification of pufferfishes using genetic marker since these species are recently commercialized for human consumption.

Monthly variations in crustacean zooplankton abundances in Sundarapandian Pattinam and Manamelkudi in the Palk Strait, India (9-10°N, Arabian Sea)

Abstract The present investigation has been made to study the distribution of crustacean zooplankton, and its qualitative and quantitative composition, as well as for making an assessment of species abundances and of the evenness of zooplankton in two habitats along the Palk Strait, between the east coast of Tamil Nadu (India) and Sri Lanka. The sampling programme was executed from July 2005 to June 2006. The two sampling sites, Sundarapandian Pattinam (Station I) and Manamelkudi (Station II), respectively, are located in one of the most productive marine zones of the world. The various groups of crustacean zooplankton were Ostracoda, Copepoda, Amphipoda, Isopoda, Cumacea, Euphausiacea, and Decapoda. Maximum occurrences were observed during the summer and the pre-monsoon seasons, and minimum occurrences were observed during the monsoon months. The present study showed that the distribution pattern of total zooplankton fluctuated at both stations. Station II is richer in absolute abundance in comparison with Station I.