Thondi Coast Research Articles

Evaluation of water quality and bioaccumulation of metals in commercially important fishes: a human health concern.

The present study aimed to determine the physicochemical properties of the coastal water and metal concentration in the muscle tissues of five commercially important fish species (Leiognathus equulus, Lates calcarifer, Sillago sihama, Scolopsis bimaculatus, Lutjanus fulviflamma) along Thondi coast, as well as the potential human health risks on consumption of these species were also studied. Water quality parameters, such as mean temperature (31.3 ± 1.86°C), salinity (28.35 ± 0.79‰), pH (7.95 ± 0.22), TDS (12840 ± 1.49mgL-1), TSS (310 ± 0.51mgL-1) and DO (5.99 ± 0.14mgL-1) were obtained. Various nutrients such as calcium (300.0 ± 36.05mgL-1), inorganic phosphate (0.186 ± 0.02μgL-1), magnesium (1077.6 ± 107.01mgL-1), nitrate (1.584 ± 0.31μgL-1), nitrite (1.179 ± 0.34μgL-1), silicate (29.717 ± 1.93μgL-1) and total phosphorus (0.153 ± 0.08μgL-1) were also analysed. The concentration of metals As, Cd, Cr, Cu, Pb and Zn in the muscle tissue was determined using atomic absorption spectroscopy (AAS). Arsenic, Cu and Pb were found to be highest in S. sihama; 1.2364 ± 0.12, 1.6102 ± 0.28 and 1.0103 ± 0.21μg/g respectively. Cadmium and Zn were found maximum in S. bimaculatus; 0.0876 ± 0.04 and 1.0564 ± 0.16μg/g respectively, whereas Cr was found highest in L. Calcarifer; 1.6781 ± 0.18μg/g. Compared our results with FAO/WHO/EU regulations. The estimated daily intake (EDI) specifies that there is no risk of consuming these species. However, the target hazard quotient (THQ) in As is found to be > 1 in these fish species, which implies a possible danger to consumers.

Seasonal changes in physico-chemical parameters of Thondi Coast waters, Palk Bay,South East coast, India

Seasonal changes in physico-chemical parameters of Thondi Coast waters, Palk Bay,South East coast, India

Baseline study of trace metal concentrations in abandoned, lost or otherwise discarded fishing gear along Thondi coast, Palk Bay, India

The Abandoned, Lost or otherwise Discarded Fishing Gear (ALDFG) are commonly found in the ocean these days due to the negligence of the fishermen. The present study aims to identify the discarded fishing gear sample and determine metals' absorption rate by ALDFGs. The identification of the ALDFG was done with the help of ATR-FTIR in which it was confirmed that the samples are mostly made of nylon 6. Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR) peaks such as 3435.43 cm−1, 2926.38 cm −1, 2857.74 cm−1 correspond to nylon 6. Adsorption of trace metals by Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS) confirmed the presence of elements such as Aluminium, Barium, Cadmium, Calcium, Chromium, Cobalt, Copper, Iron, Lead, Magnesium, Manganese, Nickel, Phosphorus, Potassium, Rubidium, Sodium, Strontium, Vanadium and Zinc in the identified plastic sample. The Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy (SEM-EDX) micrographs were confirmed the adsorption of elements by the surface of the sample and revealed the level of adsorption of trace metals in the abandoned, lost or otherwise discarded fishing gear.

Sources, spatial distribution, and abundance of marine debris on Thondi coast, Palk Bay, Southeast coast of India

BackgroundThe Thondi coast is rich in valuable natural marine resources and socio-economically significant activities like agriculture, aquaculture, and fishing. The area receives an excess of untreated solid and liquid waste as a result of these activities. The study focuses on the abundance, distribution, and status of the Clean-Coast Index (CCI) of marine debris from the Thondi coast, Palk Bay, Southeast coast of India. This is the first research work focused on assessing the type and quantity of marine debris on the Thondi coast.ResultsA total of 1636 marine debris items/m2 and their 4.09 concentration of the items/m2 were determined in the marine debris: plastics (77.49%), cotton swabs (8.62%), cigarette butts (10.15%), and food containers (3.73%). From the result, the CCI had ranged between 4.25 (clean) and 20.4 (extremely dirty) with a mean of 8.92 (moderate) in the Thondi coast assessed.ConclusionThis study was conducted for the first time in this region. Finally, the high CCI value of 20.4 on the coast indicated that the marine debris pollution levels were high at the time of sampling in the middle part of the Thondi coast (most of the beaches are covered with plastic) due to land-based marine debris (62.45%), sea-originated marine debris (21.14%), and unknown sources (16.41%) of the items. Our findings served as a baseline for potential evaluations of the marine environment. Input prevention should be the goal of management efforts, including proper waste management, plastic recycling, and stringent penalties for illegal waste dumping.

Heavy metal pollutants and their spatial distribution in surface sediments from Thondi coast, Palk Bay, South India

BackgroundThe concentration of heavy metals and their spatial distribution in surface sediments collected from the Thondi coast, Palk Bay, South India were analysed in this study. The sediment grain size, pH, EC, and major elements (Fe, and Al), heavy metal concentrations (Mn, Cr, Zn, Cd, Ni, Cu, and Pb) were determined and the values for the geoaccumulation index (Igeo), enrichment factor (EF), potential contamination index (Cp), potential ecological risk index (RI), contamination factor (CF), modified contamination degree (mCd), degree of contamination (Cd), and potential contamination factors (Cp) were calculated based on their background values to determine the pollution level of the study area. Multivariate analysis such as Pearson’s correlation coefficient, principal component analysis/factor analysis (PCA/FA), cluster analysis, and regression analysis are a versatile method for identifying heavy metal sources and determining the relationship between pollutants in marine sediment.ResultsThe pollution indices, namely EF, CF, Cd, mCd, CP, RI, and Igeo, revealed that the heavy metal contamination was due to Cd, while a moderate level of contamination was caused by Cu, Zn, Pb, and Cr. The principal component analysis and correlation matrix analysis showed a strong positive loading for Cd due to its high level of contamination in the study area. Anthropogenic inputs such as municipal wastewater, domestic sewage discharge, fishing harbour activities, and industrial and aquaculture wastes led to the increased Cd concentration in the study area. Moreover, the pollution load index revealed that the sediments were polluted by heavy metals.ConclusionThe findings of this study revealed that the increased concentration of heavy metals in the study area increases the toxicity in the marine environment, thus affecting the ecosystem.

Seasonal variation of heavy metals in seagrasses along Thondi coast, Palk Bay, India.

The present study deals with the bioaccumulation of heavy metals in different seagrass species (Syringodium isoetifolium, Halodule pinifolia, Cymodocea serrulata, Halophila ovalis) along Thondi coast and decaying seagrass offshore. Heavy metal concentrations in the seagrass samples were analysed during the period of April 2019 to March 2020 using atomic absorption spectrophotometry. Among the heavy metals assayed, the level of manganese was higher (15.62 ± 1.02 mg/kg) and chromium was the least metal observed (0.002 mg/kg). One-way ANOVA revealed significantly higher level of heavy metals in summer season, while it gradually decreased through pre-monsoon to monsoon season (P < 0.05). Cadmium and chromium were observed to be below detectable levels in the seagrass species. S. isoetifolium was found to bioaccumulate higher levels of heavy metals than the other seagrass species studied. Elucidation of heavy metal levels in the dead and decayed seagrass offshore revealed a higher level of heavy metals than live seagrass species.

Ecology and Occurrence of Pugilina (Hemifusus) cochlidium and Pugilina erecta (Gastropoda: Melongenidae) from Thondi coast , Palk strait in Tamil Nadu

The environment is a selective force of an organism and its population. Knowledge of the environmental parameters of study area is thus an essential prerequisite to understand the composition of animal’s inhabitants and their distribution. In the present study the Ecology and Occurrence of two species of Pugilina (Hemifusus) cochlidium and Pugilina erecta along the coast of Thondi are influenced by the environmental factors with less significance. As these animals are bottom living, they were not much affected by changes in the environmental factors. In the present study the maximum temperature was recorded during summer season and the minimum during monsoon. The changes in the temperature have been proved to have meager influence in the distribution of these two species as the temperature variation was not sufficient enough to affect their distribution.Keywords: Pugilina (Hemifusus) cochlidium, Pugilina erecta, temperature, monsoon, distribution.

Heavy metals accumulation in seagrasses collected from Palk Bay, South-eastern India

Metals such as Cd, Pb, Cu and Zn were analysed in five seagrass species from five locations of the Palk Bay coast of south-eastern India. The maximum Cd concentration (2.83 ± 0.08 μg g−1) was recorded in Syringodium isoetifolium on the Mallipattinam coast in the post-monsoon season, and the Cu (29.54 ± 1.03 μg g−1) in Enhalus acoroides of the Thondi coast during monsoon season. The maximum concentrations of Pb (3.12 ± 0.14 μg g−1) and Zn (52.66 ± 0.88 μg g−1) were observed in S. isoetifolium and Cymodoceae rotundata on the Devipattinam and Karangadu coasts, respectively, during the monsoon season. The metal concentrations obtained in different seagrass species varied significantly among species, and no clear monsoon season had a clear effect on the accumulation of heavy metals in the investigated seagrass species. S. isoetifolium has higher capacity for Cd and Pb accumulation than other tested seagrass species.

Metals accumulation in edible marine algae collected from Thondi coast of Palk Bay, Southeastern India

This study aimed to monitor the concentrations of metals including Cd, Pb, Cu and Zn in commercially important and commonly edible brown, red and green algal species collected from Thondi coast, southeast India. Green seaweed Chaetomorpha linum contained higher (Cd 8.51 mg kg−1, Pb 5.24 mg kg−1, Cu 15.38 mg kg−1, and Zn 22.34 mg kg−1) concentrations of metals than other tested seaweed samples. The concentrations of metals significantly varied within and between the investigated species of seaweed samples (P < 0.05). It was revealed that Cd, Pb, Cu and Zn metals were present in the species of seaweeds at different concentration. The residual levels of metals were less than the maximum allowable levels specified for human consumption compared to PTWIs, JECFA, FAO/WHO, FSSAI and EC. This study suggested that exposure to the analysed metals (Cd, Pb, Cu and Zn) through seaweeds consumption does not raise serious health effects to consumers and it is safe for human consumption.

Isolation, identification and characterization of the bioluminescent bacteria isolated from the blue swimmer crab Portunus pelagicus along Thondi Coast and virulence studies at high temperatures

The current study was conducted to isolate the marine bioluminescent bacteria from the blue swimmer crab Portunus pelagicus along the Thondi Coast. Morphological, biochemical and molecular characterization techniques including 16S rRNA gene sequencing and phylogenetic analyses confirmed that the isolated strain was Vibrio harveyi. Experiments were further carried out at different temperatures and various time intervals and the results revealed a significant effects of high temperature and extended time duration on elimination of V. harveyi. Hence, high temperature treatments could facilitate the suppression of V. harveyi from sea food and thereby, preventing food borne infections during human consumption.

Three New distributional records of Pen Shells (Bivalvia: Pinnidae) from Seagrass beds of Palk Bay Area in Tamil Nadu

The new occurrence of Three species of bivalves from Pinnidae family is recorded for the first time from Palk Bay area based on a live and dead shells collected from the Intertidal area . All the three species are under the family of Pinnidae, Pinna bicolor, Pinna deltodes and Pinna incurva . In seagrass bed of Thondi Coast, all the species of Pen shells Pinna bicolor, Pinna deltodes and Pinna incurva were embedded in muddy sand and found associated with seagrasses at inter-tidal area. It was also found buried in hard substratum associated with living zoanthids and soft coral. The collected specimens were identified as, (1) Pinna bicolor, (2) Pinna deltodes and (3) Pinna Incurva by using both morphometric and meristic characters. The paper described the taxonomic status and the description of the three species of bivalves collected from Palk Bay areas.

Abnormal Starfish, Pentaceraster regulus from Thondi, East Coast of India

Starfish Pentaceraster regulus was collected from Thondi coast, this species usually have 5 arms. An unusual, abnormal sea star, P. regulus was found with only 4 arms. Then it was length, weight arm’s length were measured and tabulated.

In vitro antiplasmodial activity of marine sponge Clathria vulpina extract against chloroquine sensitive Plasmodium falciparum

ObjectiveTo explore the antiplasmodial potential of marine sponge Clathria vulpina (C. vulpina) against chloroquine sensitive Plasmodium falciparum (P. falciparum). MethodsThe marine sponge C. vulpina was collected from Thondi coast, authenticated and subjected for extraction by soaking in ethanol:water mixture (3:1 ratio). The percentage of extract was calculated. Filter sterilized extracts (100, 50, 25, 12.5, 6.25, 3.125 μg/mL) were screened for antiplasmodial activity against chloroquine sensitive P. falciparum. The extract was also tested for its hemolytic activity. ResultsThe percentage yield of extract of C. vulpina was found to be 4.8%. The crude extract of C. vulpina showed excellent antiplasmodial activity (IC50=14.75 μg/mL) which was highly comparable to the positive control chloroquine (IC50=7 μg/mL). Statistical analysis reveals that the significant antiplasmodial activity (P<0.05) was observed between the concentrations and the time of exposure. The chemical injury to erythrocytes was also carried out, which showed that there were no morphological changes in erythrocytes by the ethanolic extracts of sponges after 48 h of incubation. The extract showed slight hemolytic activity which almost equal to chloroquine at 100 μg/mL concentration (1.023%). ConclusionsThe marine sponge C. vulpina can be used as a putative antiplasmodial drug after completing successful clinical trials.

In vitro antiplasmodial activity of marine sponge Stylissa carteri associated bacteria against Plasmodium falciparum

ObjectiveTo identify the possible antiplasmodial drugs from bacteria associated with marine sponge Stylissa carteri (S. carteri). MethodsThe S. carteri samples were collected from Thondi coast and subjected for enumeration and isolation of associated bacteria. Filter sterilized extracts (100, 50, 25, 12.5, 6.25 and 3.125 μ g/mL) from isolated bacterial strains were screened for antiplasmodial activity against Plasmodium falciparum (P. falciparum) and potential extracts were also screened for biochemical constituents. ResultsTwelve samples of S. carteri were collected and subjected for enumeration and isolation of associated bacteria. The count of bacterial strains were maximum in November 2007 (34 × 104 CFU/g) and the average count was maximum during the monsoon season (203 × 103 CFU/g). Thirty two morphologically different bacterial strains were isolated from S. carteri and the ethyl acetate bacterial extracts were screened for antiplasmodial activity against P. falciparum. The antiplasmodial activity of a strain THB17 (IC50 20.56 μ g/mL) extract is highly comparable with the positive control chloroquine (IC50 19.59 μ g/mL) and 13 bacterial extracts which showed IC50 value of more than 100 μ g/mL. Statistical analysis reveals that, significant in vitro antiplasmodial activity (P<0.05) was observed between the concentrations and time of exposure. The chemical injury to erythrocytes showed no morphological changes in erythrocytes by the ethyl acetate extract of bacterial strains after 48 h of incubation. The in vitro antiplasmodial activity might be due to the presence of reducing sugars and alkaloids in the ethyl acetate extracts of bacterial strains. ConclusionsThe ethyl acetate extract of THB17 possesses lead compounds for the development of antiplasmodial drugs.

In vitro antiplasmodial activity of Clathria vulpina sponge associated bacteria against Plasmodium falciparum

ObjectiveTo identify the possible antiplasmodial drugs from bacteria associated with marine sponge Clathria vulpina (C. vulpina). MethodsThe C. vulpina samples were collected from Thondi coast and subjected to enumeration and isolation of associated bacteria. Filtered and sterilized extracts (100, 50, 25, 12.5, 6.25 and 3.125 μg/mL) from isolated bacterial strains were screened for antiplasmodial activity against Plasmodium falciparum. Potential extracts were also screened for biochemical constituents. ResultsThirty one bacterial strains were isolated from twelve sponge samples collected from Thondi coast and screened for antiplasmodial assay. The count of bacterial strains were maximum in November 2007 (19×104 CFU/g) and the average count was maximum during the monsoon season (110×103 CFU/g). The antiplasmodial activity of strain THB15 was highly comparable (IC50 = 20.73 μg/mL) with the positive control chloroquine (IC50 = 19.59 μg/mL) and 21 bacterial strains showed IC50 value of more than 100 μg/mL. Statistical analysis reveals that, significant in vitro antiplasmodial activity (P<0.05) was observed between the concentrations and time of exposure. The chemical injury to erythrocytes showed no morphological changes in erythrocytes by the ethyl acetate extract of bacterial strains after 48 h of incubation. The in vitro antiplasmodial activity might be due to the presence of sugars and alkaloids in the ethyl acetate extracts of bacterial strains. ConclusionThe ethyl acetate extract of THB15 possesses lead compounds for the development of antiplasmodial drugs.

In vitro antiplasmodial activity of marine sponge Clathria indica associated bacteria against Palsmodium falciparum

ObjectiveTo identify the possible antiplasmodial drugs from bacteria associated with marine sponge Clathria indica. MethodsClathria indica samples were collected from Thondi coast and subjected for enumeration and isolation of associated bacteria. Filter sterilized extracts (100, 50, 25, 12.5, 6.25 and 3.125 μg.mL−1) from isolated bacterial isolates were screened for antiplasmodial activity against Palsmodium falciparum and potential extracts were also screened for biochemical constituents. ResultsThe count of bacterial strains were maximum in November 2007 (19×104 CFU.g−1) and the average count was maximum during the monsoon season (107×103 CFU.g−1). Thirty one morphologically different bacterial isolates were isolated from Clathria indica and the ethyl acetate bacterial extracts were screened for antiplasmodial activity against Palsmodium falciparum. The antiplasmodial activity of a isolate THB23 (IC50 28.80 μg.mL−1) extract is highly comparable with the positive control chloroquine (IC50 19.59 μg.mL−1) and 17 bacterial extracts which showed IC50 value of more than 100 μg.mL−1. Statistical analysis reveals that, significant in vitro antiplasmodial activity (P<0.05) was observed between the concentrations and time of exposure. The chemical injury to erythrocytes showed no morphological changes in erythrocytes by the ethyl acetate extract of bacterial strains after 48 h of incubation. The in vitro antiplasmodial activity might be due to the presence of carbohydrates and alkaloids in the ethyl acetate extracts of bacterial isolates. ConclusionsThe ethyl acetate extracts of THB23 possesses novel compounds for the development of antiplasmodial drugs.

Association of bioluminescent bacteria from blue swimmer crab Portunus pelagicus (Linneaus, 1758)

ObjectiveTo screen the bioluminescent bacteria from Portunus pelagicus (P. pelagicus) at Thondi coast, Palk Strait, Bay of Bengal, India. MethodsPhysico-chemical parameter including atmospheric and surfacewater temperature, pH, salinity and dissolved oxygen were analyzed. The population of bioluminescent bacterium was screened in ambient water and blue swimmer crab of P. pelagicus (muscle, gill, hemolymph, shell) and colony forming unit (CFU) was calculated. ResultAtmospheric and surface water temperatures varied from 26.1 and 27.3 °C to 33.4 and 32.6 °C, respectively; salinity varied from 28.4% to 34.3%, pH varied from 7.6 to 8.6, and dissolved oxygen varied from 4.8 to 6.9 O2 ml/l. In addition, the maximum CFU value was identified (12.63 ×104 CFU/ml) during postmonsoon season and the minimum level (1.09 ×104 CFU/ml) identified during summer season. Further, based on the phenotypic characterizations the isolated strain were identified as Vibrio harveyi (V. harveyi). ConclusionsIt is concluded from that the incidence of V. harveyi infections was frequently identified with edible crab of P. pelagicus, throughout the study periods in different seasons.

In vitro antiplasmodial activity of marine sponge Hyattella intestinalis associated bacteria against Plasmodium falciparum

Objective To identify the antiplasmodial drugs from the marine sponge Hyattella intestinalis ( H. intestinalis) associated bacteria. Methods The H. intestinalis samples were collected from Thondi coast and subjected for enumeration and isolation of associated bacteria. Filter sterilized extracts (100, 50, 25, 12.5, 6.25 and 3.125μ/mL) from bacterial isolates were screened for antiplasmodial activity against P. falciparum and potential extracts were also screened for biochemical constituents. Results The count of THB isolates were maximum in November 2007 (20×10 4 CFU/g) and the average count was maximum during the monsoon season (77×10 3 CFU/g). A total of 29 bacteria were isolated based on the morphological characteristics and screened for antiplasmodial activity. The antiplasmodial activity of THB20 extract (IC 50 41.88 μ/mL) showed at two fold concentration of IC 50 value of the positive control chloroquine (IC 50 19.59 μ/mL) and 14 bacterial isolates showed IC 50 value of more than 100 μ/mL. Statistical analysis reveals that, significant in vitro antiplasmodial activity ( P<0.05) was observed between the concentrations and time of exposure. The chemical injury to erythrocytes showed no morphological changes in erythrocytes by the ethyl acetate extract of THB isolates after 48 h of incubation. The antiplasmodial activity of potential bacterial isolates might be due to the presence of sugars and alkaloids in the ethyl acetate extracts. Conclusions It is concluded from the present study that, the ethyl acetate extracts of THB20 posses novel metabolites for the development of newer antiplasmodial drugs.