Goa Coast Research Articles

Jellyfish Rhizostoma pulmo collected off Goa Coast (India) as a rich source of tryptophan containing collagen and its enhanced antioxidant potential.

The extraction of Rhizostoma pulmo discarded off the Goa coast, India resulted in obtaining remarkably higher yield of 47% (based on lyophilized weight) type I collagen. The amino acid composition showed presence of glycine, hydroxyproline and proline and other amino acids in consistent with mammalian collagens. Interestingly, it also possessed essential amino acid tryptophan that makes this collagen superior than other commercially available collagen products. The dose and time response anti-oxidant activity (DPPH assay) of jellyfish collagen showed increase in the percentage activity with its efficiency better than marine fish collagen. In the dose response, IC50 was found to be 11.0mg/ml. The percentage DPPH activity gradually increased from 47.58 to 81.11% with time 1-8h, respectively at concentration of 7mg/ml of jellyfish collagen. It was noteworthy to observe that the anti-oxidant activity remained 80% even after 24h of analysis. The EDX analysis showed presence of minerals like Cl, Na, Mg, K, Cu, Fe, Zn etc. essential for healthy bones. The mass assisted laser desorption ionization-time of flight mass spectrometric (MALDI-TOF MS) data showed several precursor peaks of different peptides which has been presented here for the first time. The finding showed higher production of tryptophan containing anti-oxidant collagen that will certainly enhance its benefit in neurotransmission and cognitive function.

Risk assessment of polycyclic aromatic hydrocarbon infested sediments along the coast of Goa, India.

Goa, a small state in India, is a tourist hotspot known for its coastline and beaches. Anthropogenic activities lead to pollution in the environment. Amongst many other pollutants, polycyclic aromatic hydrocarbons represent a major class of contaminants owing to their widespread distribution and protracted environmental persistence. No information is available about the levels of Polycyclic aromatic hydrocarbon (PAH) contamination in the sediments along the coastline of Goa. The study aimed to establish a baseline for PAH concentrations in the sediments along the shoreline to help comment on the pollution levels caused and thereby understand the risk and their impact on the marine life therein. The total concentration of PAHs along the selected sampling sites of the Goa coastline was 1.00 to 875 μg g-1. Maximum PAH concentrations were detected in the Divar island mangrove (875 μg g-1); the least was observed at Galgibaga beach (365 μg g-1). The results revealed that the sediment of the Goa coastline is heavily contaminated with PAH. Source apportionment of PAHs was analysed based on diagnostic ratios, and results exhibited that petroleum products and their combustion were primarily responsible for their generation. The results of risk quotients showed that the values are way above effect range median (ER-M), indicating these could pose a high risk to the ecosystem.

Insights into the Food and Feeding Habits of the Indian Mackerel (Rastrelliger kanagurta) from the Coast of Goa

The Indian Mackerel is a commercially important fish species and India contributes to world’s 90% of mackerel production. The present study deals with gut content analysis of the Indian Mackerel Rastrelliger kanagurta to determine the type of feed and the feeding habitat. The gonado-somatic index and gastro-somatic indices were determined to find out the spawning period and maturity of the fishes. The stomach emptiness was also calculated to estimate the fish appetite from the stomach content. The present study indicated that Diatoms formed the predominant planktonic feed followed by Dinoflagellates. A total of 25 different types of planktons were found to be preferred by Rastrelliger kanagurta. The gut content also revealed sand particles, fish scales and cnidarian spicules. Highest mean GSI and lowest GaSI were observed in the month of April. The stomach emptiness index revealed gluttonous feeding from November to March and comparatively gluttonous feeding in the month of April. From the present study it can be concluded that Rastrelliger kanagurta, though shows preference for diatoms (40.74%) and dinoflagellates (22.22%), the dietary preference is not limited to it, but they also exhibited preference for Crustaceans (except copepods) (14.81%), Cyanobacteria (7.40%), Copepods (7.40%), molluscs (3.70%) and Protists (3.70%). The present study analysed the food constituents and feeding habitat of the Indian mackerel through gut content analysis. The intensity of feeding was also compared to the size of the fishes, reproductive maturity and the spawning time.

Late Quaternary variations in the Oxygen Minimum Zone linked to monsoon shifts as seen in the sediment of the outer continental shelf of the eastern Arabian Sea

Multiproxy records of benthic foraminifera, pteropods, and total organic carbon (TOC) are reported from the late Pleistocene-Holocene interval of Core SK291/GC17, located off the coast of Goa (water depth 182 m), eastern Arabian Sea. Findings help unravel significant shifts in monsoon behavior and associated changes in the Oxygen Minimum Zone (OMZ). During the Younger Dryas (11900–11,600 cal yr BP) and ~ 11,600 to 9400 cal yr BP, the coast was closer to the studied core location because of the low eustatic sea level. This interval shows a higher abundance of benthic foraminifera preferring oxic bottom water condition over the suboxic group. At ~8000 cal yr BP, the decreased abundance of pteropod species Limacina trochiformis as well as lower values of TOC suggest the presence of a dry phase of the monsoon. The interval from ~7800 to 6400 cal yr BP was deposited under favorable bottom water conditions, as documented by a higher number of species (S), Information Function (Hs) and species richness of the benthic foraminiferal assemblage. The middle Holocene (~ 6200 to 4200 cal yr BP) interval is marked by a significant increase in the number of epipelagic pteropods caused by higher surface productivity and by a decreasing abundance of mesopelagic pteropods caused by the shoaling and intensification of the OMZ. The oxic group decreased drastically while the dysoxic group of benthic foraminifera increased during this interval due to the intensified OMZ. After ~4200 cal yr BP, the oxic assemblages of benthic foraminifera and pteropods suggest low productivity coinciding with the 4.2 ka dry event observed in the Indian monsoon records. The intervals with oxic assemblages of benthic foraminifera align with Bond events. Further the oxic assemblages show high frequency cycles centered at 692, 440 and 358 yr driven by solar variability, while Uvigerina peregrina , a benthic foraminifer sensitive to OMZ variability, shows high frequency cycles of 403 and 745 yr. • OMZ history of the eastern Arabian Sea during ~13,000 to 3400 cal yr BP • Winter monsoon was relatively stronger during the Younger Dryas cold interval. • The OMZ intensified and shoaled during ~6200 to 4200 cal yr BP. • Pteropod data indicates presence of a dry phase of the monsoon after ~4200 cal yr BP.

A 51 ka sedimentary sequence in a seamount basin, Eastern Arabian Sea: Records for paleoceanographic and paleoclimate conditions

• Mineral magnetic parameters reveal the state of ocean ventilation and anoxia during the last 51 ka. • The MIS 3 monsoonal intensity regulated changes in detrital influx in the EAS. • Enhanced ocean-reducing conditions were reported during the Heinrich and deglaciation periods. A 5.4 m thick sediment core at ∼ 517 m water depth from a seamount basin off the Goa coast in the Eastern Arabian Sea (EAS) is examined for the mineral magnetic, carbonate and organic carbon variability. The 51 ka BP dated record is represented by Marine Isotope Stages (MIS) 3 to 1 under varying rates of sedimentation from 1.9 to 5.2 cm/ka. Comparison with records from adjacent cores for OC, TN, and CaCO 3 , this study indicates strong coupling of the seamount basin sedimentation with paleo-oceanographic conditions governed by southwest (SW) monsoon. The mineral magnetic parameters assigned three zones of variable paleo-oceanographic-paleoclimatic conditions marked by the interplay of high coercivity (oxidative) and low coercivity (reducing) mineralogy, that can be attributed to various factors including ocean ventilation governed by bottom water inflow of oxygen-depleted Sub-Antarctic Mode Waters and Antarctic Intermediate Water flows (SAMW-AAIW). This study emphasizes the significance of seamount basins as faithful recorders of long-term thermocline changes along with strong coupling to paleoceanographic conditions.

Seasonal variations in the water quality and antibiotic resistance of microbial pollution indicators in the Mandovi and Zuari estuaries, Goa, India.

The two adjacent estuaries of the rivers Mandovi and Zuari, along the Goa coast in the central west coast of India, are a large complex aquatic system hosting diverse natural habitats. The water quality in these habitats is affected by various anthropogenic activities as they are extensively used for transportation, fisheries and various recreational activities. In the present study, changes in the water quality and levels of microbial pollution during the pre-monsoon, monsoon and post-monsoon seasons were determined. The water quality index was estimated based on the parameters: temperature, salinity, pH, dissolved oxygen, biochemical oxygen demand and nutrients. The seasonal changes in the microbial pollution load were also assessed based on the abundance of pollution indicator organisms and their resistivity towards multiple antibiotics. Results show that the water quality index status was 'poor' in the pre-monsoon and post-monsoon seasons and it was 'good' only in the monsoon period. Levels of pollution indicator organisms determined show that the counts were the highest in the pre-monsoon season, which reduced in the monsoon and further declined during the post-monsoon season. However, the estimated multiple antibiotic resistance (MAR) index suggests that bacterial isolates in monsoonal water and sediment samples have maximum resistance towards antibiotics. This shows that, though the basic water quality improved during the monsoon, possibly due to substantial dilution, the increased terrestrial inputs brought harmful pathogens into these estuarine waters, which may be of potential health risk. Understanding the ecological status of the estuarine habitats is important for successful environmental management and sustainable development.

Acetylcholinesterase Inhibition of Marine Fish (Rastrelliger kanagurta) by Organophosphorus Pesticides as Biomarker of Neurotoxicants

This paper evaluated the inhibitory effects of various phosphorothioates (Ethyl parathion and Chlorpyriphos) and phosphates (DDVP, Monocrotophos and Phosphamidon) on acetylcholinesterase (AChE) of marine Mackerel fish (Rastrelliger kanagurta) from the Goa coast. The characteristics of the AChE enzymes isolated from different tissues of the fishes for their affinity towards the substrate were determined by the Michaelis Menten constants. The pseudocholinesterase activity was also measured in the muscle tissues in terms of Butyryl-cholinesterase (BChE) activity of the fish. The AChE activity was found to be predominant in the Brain, gills, liver and muscle tissues. However, no significant BChE activity was observed in the muscle tissue. Among the five organophosphorus pesticides, DDVP was found to be most toxic with least I50 values (0.99±0.04nM) followed by Chlorpyriphos (I50, 24.59±2.86 nM), Ethyl Parathion (I50, 183.21±11.68 nM), Monocrotophos (I50, 13536.93±1292.94 nM) and Phosphamidon (I50, 21433.1±2651.96 nM) in the decreasing order. The I50 values of all other pesticides decreased considerably with respect to DDVP. The relative neurotoxicity of the pesticides decreased by an order of magnitude in the case of Chlorpyriphos followed by Ethyl Parathion by an order of magnitude whereas in the case of Monocrotophos and Phosphamidon the toxicity decreased significantly by an order of magnitude. The variation in the muscle AChE inhibition by the organophosphorus pesticides can be attributed to the sensitivity of the enzyme for each of the pesticides as observed by the bimolecular inhibition constants (KII). The muscle AChE inhibition of Rastrelliger kanagurta can be used as biomarker for bio- monitoring of neurotoxic contaminants in the marine environment.

Occurrence of thraustochytrids: the fungoid protists vis-a-vis marine macroalgae (seaweeds) along the coast of Goa, India

Abstract Thraustochytrids are fungoid protists ubiquitous in the marine environment and found to be associated with decaying macroalgae. Not much is known about their association with living macroalgae. Hence in the present study, different macroalgal samples were collected from various beaches of Goa to examine the presence of thraustochytrids during a four-year-long study. Brown, red and green algae were found to be substrata of thraustochytrids. Thraustochytrids were isolated on pine pollen baiting from 17 to 58% of the specimens. Thraustochytrids isolated from various macroalgae belonged to the genera Oblongichytrium, Schizochytrium, Ulkenia, and Thraustochytrium. Labyrinthula sp. was also found once on the green alga Bryopsis hypnoides. These were generally found during dry seasons rather than in monsoons. The seasonal occurrence of thraustochytrids was found to be associated with temporal variation in macroalgal diversity. The statistical analysis supported individual or interactive effects of both factors viz, seasons and macroalgal diversity, on the occurrence of thraustochytrids. Thraustochytrids were also isolated from seawater adjoining macroalgae and from estuarine water at all times of the year. Oblongichytrium sp. was isolated from the green alga Ulva compressa and Anjuna seawater samples at the same time, thus indicating that thraustochytrids from seawater could inhabit the macroalgae.

The suitability of surface waters from small west-flowing rivers for drinking, irrigation, and aquatic life from a global biodiversity hotspot (Western Ghats, India).

The present study provides surface water types and water quality indices (WQI) for 70 large coastal rivers of the Western Ghats (WG). Irrespective of seasons and lithology, concentration of cations (Ca2+ > Na+ > Mg2+ > K+) and anions (HCO3- > Cl- >SO42- > NO3- > PO43-) follow a typical trend all along the coast. The WG rivers can broadly be classified as calcium-bicarbonate-chloride (Ca2+-HCO3--Cl-) type. Pearson correlation analysis of major ions demonstrates natural sources influence on the riverine water composition across the WG region. Gibbs plot suggests water composition of these rivers is the result of the interaction of rock and precipitation. It means that ionic contributions from precipitation and chemical weathering of rock-forming minerals largely determine surface water quality. This biodiversity hotspot is facing high population pressure and anthropogenic activities. Despite it, quantitatively, all the physical parameters and chemical constituents are within the permissible limits of the World Health Organization (WHO) and Bureau of Indian Standards (BIS), thus making it suitable for drinking and domestic purposes. About 86% of the surface water samples are found to be suitable for irrigation (KR < 1) in non-monsoon seasons. Rivers near to Goa coast are only found unsuitable (KR > 1) for irrigation exclusively during non-monsoon seasons. From the majority of the calculated indices, it may be inferred that the river waters draining from the WG region are suitable for irrigation. Overall, the calculated WQI for studied rivers showed excellent to good water quality for drinking, agriculture, and aquatic life in monsoon seasons, which are then ranked from good to marginal in non-monsoon seasons.

Status of Coastal Marine Biodiversity of Goa and Challenges for Sustainable Management - An Overview

Degradation of marine and coastal ecosystem can be seen everywhere and Goa is no exception. Biodiversity provide important services to mankind and needs to be protected. Goa is endowed with varied microhabitats along its 105 long coast line. These habitats are home to diverse forms of life about which little is known. The coastal waters serve as nursery to fishes and other animals which are exploited commercially. The present communication reviews the current status on the taxonomic knowledge of the coastal biodiversity of Goa. The coastal water of Goa abound in flora and fauna. The information on major fauna and flora of Goa is sufficiently available. There is, however, some lacunae in our knowledge on invertebrate subgroups, such as sponges, octocorals, ctenophores, and tunicates and minor phyla. The biodiversity of specialized ecosystems continued to be inadequately known and remains a challenge to specialists from Goa coast. Threat to coastal and marine biodiversity due to climate change and environmental degradation are intensifying with time. The anthropogenic activities are causing damage to pristine coastal ecosystems. The loss of biodiversity will be felt in greater strength by future generation. The present knowledge on coastal biodiversity warrants continued taxonomic research in the least-studied or unknown groups of hot spot areas in the light of existing threats to marine biodiversity. It is suggested that further research on new species occurrences in the least studied groups should be continued to update the data and improve our knowledge. The appropriate measures will be required to protect the rich biodiversity resources of Goa.

Assessment of microplastic pollution in the aquatic ecosystems – An indian perspective

Microplastics (MPs) are ubiquitous in the aquatic environment due to plastic waste proliferation in diverse sectors. The recent years have witnessed exponential growth in the number of studies focusing on their occurrence, distribution and toxicity in several parts of India. The overarching aim of this article is to evaluate the sources, abundance, and characteristics of MPs reported in the sediments, water, and biota of the aquatic ecosystems in India. The review revealed that while the MPs from land-based sources such as littering, domestic sewage, and industrial runoff were carried by rivers and streams, MPs from other sources including marine litter and accidental spillages during shipping directly enter the aquatic environment. The unique hydrodynamic conditions during the southwest and northeast monsoons were found to influence the abundance and distribution of MPs in the Indian aquatic ecosystems. Although the seaward flushing and monsoonal flux were reported to increase the abundance of MPs, the reversal of the winds and currents during the NE monsoon was observed to oppose the drift of MPs towards the Goa coast. The reported higher concentrations of MPs in the beach sediments collected from the high tide line (1323 ​± ​1228 ​mg/m2) as compared to that of low tide line (178 ​± ​261 ​mg/m2) along the southeast coast of India also emphasize the tidal influence. While the shape and type of MPs can help in determining their sources, their size and colour might influence their ingestion in aquatic biota and also indicate the amount of degradation. The variability in the characteristics of MPs observed between different studies could also be a factor of difference in the sampling and analysis techniques adopted. Although the general practice of degutting before consumption could lower the risk of MPs transfer from fish, popular delicacies of dried fish and shrimps could be potential sources of human ingestion. Since the research was mostly confined to the southern coasts of India and some urban recreational beaches, the MP pollution on other coastal regions of India remains largely unexplored. Moreover, with very few studies reporting on the MP pollution in the freshwater ecosystems, the wide network of rivers and enclosed water bodies could also be the major focus of future research.

Assessment of Aquifer Vulnerability Using GALDIT Model – A Case Study

Abstract With the increasing urbanization, agriculture, industrial activities along the coastal stretches of India, more and more people depend on ground water due to which there are cases of large scale decline in both quantity and quality. One of the State which is facing a critical change in its geomorphology and land use/land cover is Goa which is known for its tourism industry. Therefore, the water management will be a major issue in the years to come. A field survey conducted in parts of north Goa coast to understand the ground water availability status, quality issues and salinity conditions of ground water due to sea water intrusion. Accordingly, an attempt was made to understand the extent of seawater mixing with ground water using a model known as GALDIT Model. GALDIT is an indicator based model which assess and quantifies the significance of vulnerability to seawater intrusion due to excessive groundwater withdrawals. The system contains three significant parts: weights, ranges, and ratings. Each GALDIT factor has been evaluated with respect to the other to determine the relative importance of each factor. Accordingly indices were calculated for the selected wells (wells were selected along the coast and also perpendicular to the coast). Results obtained by GALDIT model showed that about 42% of the wells in the study area are low vulnerable and 58% of the wells are moderately vulnerable to sea water intrusion.

Marine soundscape and fish chorus in an archipelago ecosystem comprising bio-diverse tropical islands off Goa Coast, India

Many biological sources of sound in tropical coastal shallow-water marine environments remain unidentified. Characterizing the soundscape of such environments requires that all sources of biological sound be examined for their distinct patterns and specific frequency ranges. The present study identified soniferous fish in the ecosystem and measured underwater ambient sound in terms of its sound pressure levels (SPL) to quantify and characterize their contribution to the soundscape. Underwater SPLs were measured from 2012 to 2016 at a site near Grande Island Archipelago (15° 18′ N, 73° 41′ E) 18 km off the coast of the state of Goa, which lies along India’s western coast. Acoustic data were recorded using three types of methods for passive acoustic monitoring, namely a hanging hydrophone, five seabed-mounted hydrophones and an autonomous moored vertical hydrophone. Underwater visual census at the site revealed that both species richness and diversity were high indicating the Grande Island Archipelago is a bio-diverse site. The seabed-mounted hydrophones proved to be the best choice for long-term SPL measurements, although the moored arrays were more economical. Ambient sound levels underwater varied markedly over time both within a day and with the season. Long-term SPLs were above 100 dB re 1 μPa over frequencies 62.5–8000 Hz and peaked to 120–130 dB re 1 μPa between frequencies 500 Hz and 1000 Hz, corresponding to the chorus frequencies of soniferous fish at the site. High SPLs and marked temporal variations of the soundscape indicate the abundance, diversity and life activities of fish species and healthy ecological state of the bio-diverse archipelago.

Response of shallow-sea benthic foraminifera to environmental changes off the coast of Goa, eastern Arabian Sea, during the last ∼6100 cal yr BP

AbstractWe have analysed a 6100-year record of benthic and planktonic foraminifera from inner neritic sediments from Core SK291/GC13, off the Goa coast, eastern Arabian Sea, to understand the response of benthic foraminifera to shallow-marine processes. The benthic foraminiferal assemblage is dominated by Nonion cf. asterizans, Ammonia beccarii, A. gaimardii and Virgulinella fragilis, which have been selected on the basis of a population of 10% or more in any three samples analysed. The planktonic foraminiferal population is sporadic and rare, with Globigerinoides ruber as the predominant species showing a variable trend. The foraminiferal proxies combined with total organic carbon (wt%) and δ13C and δ18O values of Ammonia gaimardii suggest distinct variations, indicating changes in productivity and salinity in the shallow eastern Arabian Sea. The coastal waters off Goa were relatively warmer and less saline between 6100 and 4600, or perhaps to 4200, calibrated years before the present (cal yr BP), corresponding to a stronger monsoon in South and East Asia. The shallow sea was cooler from ~4200 to 2600 cal yr BP in the study area, coinciding with a lower sea surface temperature in the northeastern Arabian Sea and an arid phase in the Indian subcontinent. From 2900 to 2600 cal yr BP the study core exhibits the impacts of short-term cold events, which have earlier been observed in the northeastern Arabian Sea, off Pakistan. During the Little Ice Age, the shallow sea off Goa was less productive.

Oil pollution in the Eastern Arabian Sea from invisible sources: A multi-technique approach

The Eastern Arabian Sea (EAS) is affected by oil pollution, as often evidenced by the presence of tarballs along the West Coast of India (WCI). Tarball samples collected during May 2017 along the Goa coast were subject to biomarker fingerprints, and the results matched with Bombay High (BH) oil fingerprints. The present study primarily aims at identifying the potential minor spill areas using Sentinel-imagery. Interestingly, repeated occurrence of oil spills detected at two locations, perfectly matched with BH platforms. The simulated Lagrangian trajectories also depict that tarball particles have originated from those detected locations. In 2017 alone, the quantity of spilled oil was estimated to be 129,392 l. However, spills detected offshore regions of Kachchh and Mangalore were found to be caused by ships. This is the first comprehensive study, tracking the oil pollution sources in the EAS through multi-technique approach - chemical, remote sensing and numerical modeling.

Late Holocene long arid phase in the Indian subcontinent as seen in shallow sediments of the eastern Arabian Sea

Multi-proxy record of benthic and planktic foraminifera, total organic carbon and carbon and oxygen isotope ratios from Core SK291/GC15, off the coast of Goa, eastern Arabian Sea reveals significant paleoceanographic and paleoclimatic turnovers during ~6000 to 1700 calibrated years before the Present (cal yr BP). Benthic foraminiferal census data was analyzed with multivariate techniques including factor and cluster analyses of highest ranked species from the studied core that enabled to identify seven biofacies. The record suggests centennial to millennial-scale changes in the surface conditions driven by monsoon-linked upwelling in the eastern Arabian Sea during the studied interval. Various benthic biofacies combined with isotope and planktic foraminiferal data suggest that depletion of dissolved oxygen and increase in organic productivity in the study area was caused by intense monsoonal upwelling since the middle Holocene. The results suggest that during 5400–4700 and 3000–2500 cal yr BP the southwest (SW) monsoon was strong leading to intense upwelling in the study area as reflected by increased Globigerina bulloides percentages. These were generally warmer intervals in the northern hemisphere. The SW monsoon significantly weakened (abrupt decrease in G. bulloides population) during 4700–3400 cal yr BP roughly coinciding with a long arid phase in the Indian subcontinent and a cold interval in Europe. Our record suggests an abrupt increase in SW monsoon intensity during ~3000 to 2500 cal yr BP, when a pronounced change in benthic biofacies is also noted that suggests a major shift in the sub-surface conditions. Our data document a prolong weak SW monsoon phase beginning at ~4600 cal yr BP, little earlier than 4.2 ka event, in the eastern Arabian Sea.

Biological activities of marine Actinobacteria isolated from West Coast of Kerala and Goa: A screening and pilot scale optimization study

Biological activities of marine Actinobacteria isolated from West Coast of Kerala and Goa: A screening and pilot scale optimization study

Characterization of a new virulent phage ϕMC1 specific to Microbulbifer strain CMC-5

Microbulbifer strain CMC-5, isolated from decomposing seaweeds degrades agar, alginate, carrageenan, chitin, carboxymethyl cellulose and xylan. Using bacterial strain CMC-5 as host, a novel virulent phage, designated ϕMC1 was isolated from the coast of Goa, India. Although ϕMC1 demonstrated cross infectivity with type species of Microbulbifer such as M. agarolyticus JAMBA3T and M. celer KCTC 12973T, it did not infect M. mangrovi KCTC 23483T, M. salipalidus JCM 11542T, M. elongatus DSM 6810T and M. hydrolyticus IRE-31T. The one step growth experiment of ϕMC1 infecting bacterial strain CMC-5 at a multiplicity of infection of 0.1, revealed a latent period of 60 min and a burst size of 180. TEM analysis of ϕMC1 indicated it to be a tailless phage with an icosahedral head having a diameter of 60 ± 1.42 nm. The ds DNA of ϕMC1 was restricted by EcoRI, HindIII and SmaI whereas HaeIII, BamHI, PstI, NotI did not cleave the DNA. The molecular size of ϕMC1 DNA was analyzed by restriction digestion as well as pulsed field gel electrophoresis and was estimated at 48.5 kb. The phage infectivity was adversely affected by organic solvents demonstrating the presence of a lipid membrane. The inhibition of ϕMC1 infectivity by EDTA was abolished by addition of Ca and Mg salts.

Hemotoxic and wound healing potential of coelomic fluid of sea-star Astropecten indicus

BackgroundThe coelomic fluid of echinoderms bathes all the internal organs and is a natural reservoir of various bio-active compounds. However, coelomic fluid from Indian sea-star Astropecten indicus is not well characterized for its biochemical and pharmacological profiles. Sea-star (or starfish) Astropecten indicus was collected from the coast of Goa, India during low tides. Sea-star coelomic fluid (SCF) extracted from the sea-stars was concentrated, filtered, and assayed for various hemotoxic activities such as fibrinogenolysis, fibrinolysis, hemolysis, and effects on platelet aggregation.ResultsStudies on effects of SCF on A-549 human lung cancer cell line showed its non-cytotoxic and wound healing abilities in vitro. SCF was found to possess fibrinogen and fibrin digesting ability at a dose of 4 μg/ml within 30 min of incubation with the substrate. Additionally, SCF could hemolyze goat RBC by 50% and human RBC by only 5%. SDS-PAGE analysis showed that SCF contains various proteins and peptides. Two protein components of SCF yielded strong fibrinolytic, fibrinogenolytic, caseinolytic, and gelatinase activities as revealed by zymography. SCF enhanced the aggregation of ADP and collagen-activated platelets in a dose-dependent manner and had a specific proteolytic activity of 2.5 μg/ml in 30 min at 37 °C as assayed using azocasein as substrate.ConclusionThis study focuses on the anticoagulant, pro-platelet aggregation and cell proliferative potential of SCF in vitro and is the first report on hemotoxic and wound healing potential of coelomic fluid of Astropecten indicus.

Seasonal variations and relationships between environmental parameters and heavy metal concentrations in tissues of Crassostrea species and in its ambience from the tropical estuaries.

This study aimed to evaluate the relationship between physicochemical parameters and heavy metal (Cu, Ni, Pb, and Cd) concentrations from sediment, seawater, and its accumulation in tissues of oyster species (Crassostrea madrasensis and C. gryphoides) from the three sites (Chicalim Bay (CB), Nerul Creek (NC), Chapora Bay (ChB)) along the Goa coast (India). Results showed enrichment of Cu and Ni in sediment exceeding the effect range low (ERL) level. The higher concentrations of Cu and Ni in sediments and in suspended particulate matter (SPM) from all the study sites are indicative of severe contamination of estuarine and associated habitats. Moreover, particulate Ni (at all the sites), Cu (at NC and ChB), Pb (at NC), and Cd (at CB and NC) concentrations were recorded more than its total loadings in surface sediment. Concentration of Cu and Cd in oyster tissue was several folds higher than its concentration in ambience. Further, this study showed that the levels of metal in oysters and their ambient environment were higher during the monsoon season. Hence, the consumption of oysters needs to be considered carefully with respect to the health hazards posed by the elevated levels of metal contaminants in certain seasons. The present study concludes that metals associated with the particulate matter in water column are the main source of metal accumulation in oyster. It is also suggested that concentration of metal pollutants in coastal and estuarine water bodies should be monitored regularly to ensure the acceptable limits of metal concentrations.