Search

The environment plays a major role in determining the abundance of fishes in a particular region and it helps to predict the probable fishing zone. This environment variables includes temperature, salinity, pH, TSS, DO (Dissolved Oxygen), chlorophyll a, b and c, primary productivity, gross and net, nutrients, phosphate, nitrate and ammonia. These parameters were estimated using standard procedures. These parameters in a particular fishing zone varies from season to season. This seasonal variations of these parameters and its relationship with each other are studied in Ennore, (Lattitude, 80°19’31"E, and Longitude, 13°14’51"N). an industrially polluted area along Chennai coast. Factor analysis is done to remove the redundant highly correlated variables from the data, replacing the entire data with uncorrelated variables. During the post monsoon season, the 4 components extracted by factor analysis indicates that the nutrient, nitrate, chlorophyll b, TSS and dissolved oxygen are important variables deciding the photosynthetic activity, in summer season, 3 components were extracted and the variables that decide photosynthetic activity includes nutrient nitrate, temperature and nutrient ammonia. In pre-monsoon season, 5 components were extracted by factor analysis and the deciding variables include pH, chlorophyll, c, chlorophyll a, chlorophyll b and salinity. In monsoon season, 3 components were extracted and the deciding variables include TSS, DO and temperature for the photosynthetic activity to take place. The eigen values worked out in all the 4 seasons are above 1 and are reliable. The eigen value is highest in the post monsoon component tested, 4.39 and the least eigen value, 1.05 is in the pre monsoon season. Pre monsoon season among all seasons shows highest percentage of cumulative variance. In the post monsoon season, the variables N-Nitrate, chlorophyll b, TSS and DO in the components 1, 2, 3 & 4 decide the growth of phytoplankton with 12% loss of information. In the summer season, the variables, N-Nit, temp., and N-amm., in the components 1, 2 and 3 are the deciding factors for the growth of phytoplankton with 26% loss of information. In the post monsoon season, the variables, pH, chlorophyll c, chlorophyll a, chlorophyll b and salinity in the components, 1, 2, 3, 4 and 5 respectively decides the phytoplankton growth with 11% loss of information. In the monsoon season, the variables, TSS, DO and salinity in the components 1, 2 and 3 decide the growth of phytoplankton with 22% loss of information. These variables are representative of all original 11 variables and the components are not linearly correlated with each other. The size of the data from 11 variables can be reduced to three components by using factor analysis with the principal components extraction.

The knowledge of hydrographic variables is very important in determining the abundant availability of fishes in a particular region. The study site selected includes an industrially polluted area, Ennore and Chennai fisheries harbour region. The hydrographic variables selected for study includes temperature, salinity, pH, dissolved oxygen, chlorophyll a, b and c, primary productivity, gross and net and the nutrients, phosphate, ammonia and nitrate. The important hydrographic variables and its effect on the region and that influence the fish abundance throughout the year are discussed. At Ennore, the salinity level was maximum during the month of July, 37.00 ppt at a lowest temperature of 27.00 °C and at a highest temperature of 31.00 °C in the month of Sept’09, the salinity level was 32.00 ppt. At Chennai fisheries harbour, the lowest temperature recorded was 26.40 ºC at Jan’09 and the highest temperature was 30.0 ºC at April’09, lowest salinity level was 26.80 ppt at Feb’09 and highest salinity level was 38.50 ppt at July’09. The variations among months and from 2 different locations viz. Ennore and Chennai Fisheries harbour were studied during the entire year. The interaction effects between the two locations were also studied. Temperature, salinity, chlorophyll a, b and c primary productivity, gross and net are non significant p0.05 at Ennore and at Chennai Fisheries harbour location. The response optimization of the different hydrographic variables viz. temperature, 28.14 °C, salinity, 30.80 ppt, pH, 6.37, dissolved oxygen, 3.12 ml/l, and total soluble solids, 0.40 mg/l for a predicted response of chlorophyll a of 3.35mg/m3 at Ennore and at Chennai Fisheries harbour region the hydrographic variables viz. temperature, 30.00 °C, salinity, 26.80 ppt, pH, 6.38 dissolved oxygen, 2.86 ml/l and total soluble solids of 0.40 mg/l for a predicted chlorophyll a response of 1.88mg/m3 were worked out.

Phytoplankton is the major food of zooplankton and small pelagic occurring along the Chennai coast. The distribution of phytoplankton vary from place to place and the occurrence of different species decides the biodiversity of the ecosystem. This paper describes the occurrence and the characteristics of most common phyto organisms along the Chennai coast using primer 6.0 software. The phytoplankton distribution consists of dissolved volume, Ceratium species, Navicula, Bidulphia, Nitzschia, Gyrosigma and Chlorella during the year’2011. The occurrence of the phytoplankton, Chaetoceros, 38.01%, followed by Thalasirrothrix is 11.95%, Nitzschia is 8.94%, Navicula, 8.19%, Gyrosigma is 7.22%, Bidulphia is 6.57%, Coscinodiscus, 5.85%, Pleurosigma, 5.81%, Ceratium species, 4.58%, Chlorella is 2.74% and dissolved volume is 0.03% of the total phytoplankton distribution. The primer graphs for eclidean distance of different months for different species of phytoplankton were drawn. From the bray Curtis similarity graph it is evidenced that the distribution of phytoplankton component. Chaetocerus is far from the other species since its occurrence is more during the month of Jan’11. From the similarity graph, it is found that Chaetoceros and Coscinodiscus are closely related, Ceratium species and Pleurosigma are closely related, Navicula and Bidulphia are closely related. The occurrence of Chlorella is not closely related to any species. Bubble plots displays the individuals species abundances in relation to the overall community pattern. Funnel graphs are drawn for the number of phytoplankton. As the temperature increases during the summer month the phytoplankton decreases. The environmental variables, temperature, pH, salinity, TSS, TDS, dissolved oxygen, chlorophyll a, b and c, primary productivity, gross and net, nutrients, phosphate and ammonia vary significantly with the phytoplankton occurrence. The correlation coefficient of occurrence of Ceratium-Nitzschia (0.78), Ceratium- Thalassirothrix-(0.98), Ceratium- Pleurosigma (0.90), Navicula-Bidulphia (0.57), Navi cula-Nitzscia (0.10), Navicula -Gyrosigma (0.95), Navicula- Chaetoceros (0.93), Navicula- Coscinodiscus (0.57), Navicula-Pleurosigma (0.19), Bidulphia-Nitzschia (0.50), Bidulphia - Gyrosigma (0.31), Bidulphia- Chaetoceros (0.25), Bidulphia- Coscinodiscus (0.94), Nitzschia-Thalassirothrix (0.82), Nitzschia-Coscinodiscus (0.34), Nitzschia-Pleuro -sigma (0.64), Gyrosigma-Chaetoceros (0.99), Gyrosigma- Coscinodiscus (0.33), Gyro sigma-Pleurosigma (0.26), Chaetoceros-Coscinodiscus (0.26), Chaetoceros –Pleurosigma (0.30), Gyrosigma-Chlorella (0.09), Chaetoceros-Chlorella (0.05). The species richness, d varies from 0-2.40, Pielous’s index of evenness (J') varies from 0-0.97, Shannon–Wiener’s diversity index (H'), 0-2.32, simpson’s dominance index, , 0-0.9. The species richness, species evenness, species diversity and dominance index are all significant at p  0.05. The correlation between the environmental variables and the phytoplankton species distribution were worked out.

The beach litter survey of the selected beaches of Tamilnadu viz. Marina, (lat 13°055’N and long 80°28’E), Besant nagar (lat 12°99’N, long 80°27E) and Thiruvanmiyur (lat 12°97’N and long 80°26´E) were done in the year 2014. Beach litter survey was done mainly to quantify as well as to know the distribution pattern of different types of litter in all the selected beaches surveyed. The different types of litters surveyed in the year 2014 from Jan-Dec includes nylon/ HDP ropes/fishnet pieces (A), plastics covers, sachets, containers of creams, oil, ointments(B), chappals, foot wear (other than leather items)(C), glass bottles, electric bulbs, CFL bulbs (source of Hg) (D), waste (TV, Computer hard- wares, mobile phone handsets charges)(E) and Thermo col, PUF insulators of AC/Fridge, Styrofoam, etc. (F). Among the total litter distribution item C, chappals, footwear (other than leather items) is the highest (4000g/m2) followed by item B, plastics covers, sachets containers of creams, ointments, oil, (2525 g/m2), item F, thermocol, PUF insulators of AC/Fridge, stryrofoam, (1310g/m2), item D, glass bottles, electric bulbs, CFL bulbs (sources of Hg), (1125g/m2) and item A, nylon, HDP ropes and fishnet pieces, 1075 g/m2. In Marina Beach, in post monsoon season (Jan’14 to Mar’14) the item C is more than in A followed by B,D,F and E in summer season(Apr’14 to June’14) the litter distribution is more in C followed by F, B, D, A & E. In pre monsoon season (July’14 to Sep’14) the item B is more followed by C, F, A, D and E in monsoon season, (Oct’ 14 to Dec’14) the item B is followed by F,C, A, E and D. In Besant nagar beach in post monsoon season, (Jan’14 to Mar’14) the item C is more followed by D, A, B, F and E in summer season (April’ 14 to June’14) the item C is more followed by B,F,A,D and E in pre monsoon season, the item B is more followed by C,F,A,D and E in monsoon season, the item F is followed by B, A, C, D and E. In Thiruvanmiyur beach in post monsoon season(Jan’14 to Mar’14) the item C is more followed by B, A, F, D and E, in summer season, (Apr’14 to June’ 14) the item B is more followed by C,F,A,D and E in pre monsoon season, (July’14 to Sep’14) the item B is more followed by F,A,D,C and E in monsoon season, (Oct’14 to Dec’14) the item D is more followed by B,C,F, A and E. In marina beach, the PCA analysis of the beach litter for 12 consecutive months showed that the 2 components extracted had a variance of 49.02% with an eigen value of 2.45 and 25.63%, cumulative variance of 74.65% with an eigen value of 1.28. In Besant nagar beach, the PCA analysis showed that the 2 components extracted had a variance of 43.51% with an eigen value of 2.18 and 32.73% with an eigen value of 1.64 and the cumulative variance of 76.23%. In Thiruvanmiyur beach, the 2 PCA components extracted had a variance of 55.51% with an eigen value of 2.78 and 30.58% with an eigen value of 1.53 and the cumulative variance of 86.09%.

Health of an ecosystem is very much important as we depend on its goods and services for our existence. Because of this, we need to continuously monitor its health for human benefit and for identifying areas for improvement of our natural systems. The present study tries to assess the condition of a coastal ecosystem within the Vembanad Lake, Kerala, India, using key water quality parameters at micro-level. Principal component analysis identified the minimum required water quality dataset for further analysis and was scored using linear scoring functions. The weighted additive method was used to integrate the individual scores to arrive at a final score representing the ecosystem health. Spline interpolation was applied to develop the ecosystem health map of the study area. Using this method, 35.8% area of the aquatic ecosystem studied was characterized as good, 32.2% as moderate, 26.2% as fair and 5.8% as poor. The assessment results can help the policymakers/managers to make appropriate decisions for the better management of the coastal ecosystems studied. Moreover, this methodology can be replicated for the assessment of coastal regions with similar ecosystem characteristics.

Reduction of graphene oxide (GO) can be used to improve the physical and electronic characteristics of rGO through de-oxygenation and restoration of π-conjugation. Here, the gradual and controllable thermal reduction of GO film formed by drop-casting method was carried out at low temperatures (100 − 350 °C) in ambient conditions with simultaneous electrical measurements. The conductivity of GO film depended on the level of reduction. Electrical measurements show a decrease and then an increase in electrical current after > 150 °C with a maximum change of five orders in current at 300 °C in comparison to GO. The role of functional groups on the evolution of electrical conductance during reduction has been investigated by correlating the FTIR spectroscopy and electrical conductivity. It is shown that the changes in conductivity is governed by two processes, first process is mainly associated with water and OH groups desorption and second process is mainly associated with restored graphene sp2 network. The process, therefore, lends itself to the production of conductive reduced GO suitable for many applications including flexible electronics, TCO layer in solar cells, gas and temperature sensors.

A bloom of the planktonic dinoflagellate, Ornithocercus magnificus was reported for the first time in the surface waters of the off Kochi coastal region with an evidently higher density of 1.7 x 106 cells L-1 on 18.12.2019. No conspicuous colouration of the surface waters was noticed even with the higher abundance of (1.7 x 106 cells L-1) observed near the barmouth area (6-7 m). The tracking on the occurrence of this genus in this region from 2013 to 2019 revealed their occurrence only during three times over the six years, i.e. the post monsoon season of 2013 and 2014 and during pre-monsoon of 2016. The SST of the three stations of the post monsoon season was compared for the last three years from 2017 to 2019, and an evident variation in the SST distribution was noticed in this region. The SST in 2019 was 2.1°C higher than that observed during 2017. The occurrence of Ornithocercus magnificus showed a positive correlation with SST (rs =0.425, p

Recently, polymer based biomaterials are utilized in medical fields including surgical sutures, drug delivery devices, tissue supports and implants for interior bone fixation. However, polymer based implants leads to the formation of bio-films that are highly susceptible to microbial adhesion. In this study, we have fabricated Chitosan/Polyvinyl alcohol/Graphene oxide/Hydroxyapatite/gold films for potential orthopedic application. Graphene oxide/Hydroxyapatite/gold nanocomposite (GO/HAP/Au) was synthesized by simple hydrothermal method and GO/HAP/Au nanocomposite incorporated polymeric film was fabricated using gel casting method. The morphology, phase composition, crystalline structure and chemical state of the nanocomposite were characterized using as XRD, HR-TEM, FE-SEM and FT-IR. The bio-films were found to be biocompatible with mouse mesenchymal cells and it enhanced osteoblast differentiation as evidenced by more alkaline phosphatase activity at the cellular level. Hence, these results suggested that the developed nanocomposites films are osteogenic potential for treating bone and bone-related diseases. Antibacterial analysis of the films shows high inhibition zones against Gram positive and Gram Negative bacteria (Escherichia coli, streptococcus mutans, Staphylococcus aureus and Pseudomonas aeruginosa). Thus, the obtained nanocomposites bio-films are highly biocompatible and it can be used for bone regeneration application.

Pathogenic microorganism delays wound-healing process by causing infection. In recent years, researchers have developed various kinds of photo-active nanomaterials with enhanced antibacterial prope...

A study was conducted for a period of two years from 2017 to 2018 to assess the health of Tuticorin Bay, south-east coast of India. Water and sediment quality parameters, total clam density, heavy metal content in the sediment and clam tissue samples from four sites were used as the criteria for health assessment. High values of parameters like salinity (38.3±5.04 ppt) and ammonia (0.09±0.04 mg l-1) were observed at the station close to the thermal power station and high nitrite (0.688±0.13 µg l-1) and total suspended solids (380.3±0.04 mgl-1) were observed at the station close to Koramballam freshwater creek. Most of the water quality variables were within the standard limit prescribed for aquaculture activities. The organic matter content in the sediment of the bay ranged from 0.26 to 5.17%. Comparatively low heavy metal concentration was observed both in the sediment and clam tissue samples. The metals were found accumulated in the order of Fe>Mn> Pb>Cu>Ni>Cd in the sediment samples and in the order Fe>Pb>Mn>Cu>Cd>Ni in clam tissue samples. The estimated levels were also within the permissible limits for most of the metals. The study indicated that Tuticorin Bay is suitable for mariculture activities. Keywords: Clam density, Heavy metal concentration, Tuticorin Bay, Water and sediment quality parameters

Restoration of Rhizophora mucronata stand in the Gurupura Estuary resulted in improved water and sediment quality parameters. Monthly monitoring from 2011 to 2016 indicates that the restored mangroves grew to a height of 61.49 ± 5.76 cm. Principal component analysis (PCA) showed that increased duration of salinity in the estuary aided the growth of barnacles in planted mangroves which reduced survival by 10%. The United States Environmental Protection Agency ratings revealed that natural mangrove site in Shambavi River exhibit the maximum good water quality rating though dissolved inorganic phosphorous was rated highest due to non-point pollution sources. The pH, salinity, dissolved oxygen, silicate, phosphate, ammonia, and rainfall demonstrated significant seasonal differences (P 0.001). Mangrove roots and biomes aided in accumulation of clay and significant difference (P 0.001) was observed yearly. Land use management, efficient waste disposal system along with restoration of diverse mangroves can improve the water quality of estuarine ecosystem.

Wound healing is a complex multistep process. Wound healing materials should have good antibacterial activity against wound infection causing microbes. Curcumin has effective antimicrobial activity, anti-inflammatory and antioxidant property. Titanium dioxide (TiO2) is a biocompatible, nontoxic material used for many biomedical applications. The Usage of curcumin tagged TiO2 nanoparticles for wound healing activity is promising due to the properties of both curcumin and TiO2. We have synthesized curcumin tagged TiO2 nanoparticles. The synthesized materials are characterized with XRD, FTIR and TEM. TiO2-Cur nanocomposite was incorporated into poly vinyl alcohol (PVA) and sodium alginate (SA) patch. The PVA/SA/TiO2-Cur patch was prepared by gel casting method. Antibacterial efficiency of PVA/SA/TiO2-Cur patch was analyzed. Further, in vivo studies conducted on Wister rats confirmed the enhanced wound healing property of the PVA/SA/TiO2-Cur patch. Our results suggest that this could be an ideal biomaterial for wound dressing applications.

Infection and colony formation by microbes has been a negative consequence in wound care. Graphene oxide (GO) has a large surface area and it is biocompatible. Zinc oxide (ZnO) exhibits antimicrobial activity against various infectious microbes. In GO/ZnO nanocomposite, ZnO nanoparticle is homogeneously supported on the GO sheet. It controls the infection in wound area and promotes angiogenesis. The synthesized nanocomposite was characterized using XRD, FTIR, Raman Spectroscopy, UV-DRS, FESEM with EDS, TEM and ICP-OES. Antibacterial activity was studied using the well diffusion method, growth curve, death kinetics, sensitivity coefficient, biofilm inhibition and colony counting method. Reactive oxygen species assay (ROS), lactate dehydrogenase leakage assay (LDH) and DNA fragmentation studies were done to analyze the mechanism of inhibition of nanocomposite against bacteria. A hemolytic study was done to confirm the blood biocompatibility of the nanocomposites. The mechanism of bacterial inhibition is by the production of ROS, loss of membrane integrity, not by DNA fragmentation. The nanocomposites enhanced its antibacterial activity in the presence of visible light compared to dark conditions.

The growing production and widespread use of nanomaterials are a severe concern to human health. Typically, titanium dioxide (TiO2) incorporated reduced graphene oxide (RGO), and graphene oxide (GO) has grown considerably due to their wide range of applications in nanomedicine. They are used in wound healing, drug delivery, tissue engineering and biosensor. In this work, RGO/TiO2 nanocomposite was synthesized by varying the TiO2 concentration, and the toxicity assessment was done using the zebrafish embryo model. Further, the obtained RGO/TiO2 nanocomposites were characterized through SEM, TEM, XRD, XPS, FTIR, UV and Raman analysis. The RGO/TiO2 nanocomposite is found to be biocompatible. Zebrafish body length, heartbeat count and survival percentage were carefully measured in sets of controlled experiments. Especially, the RGO/TiO2 nanocomposite showed very low toxicity to the zebra fish embryos at lower concentration of 30 μg ml. Also, the toxicity of the nanocomposites increases with increase in the concentration up to 1.0 mg mL−1. RGO/TiO2 nanocomposite at higher concentration generates reactive oxygen species (ROS) and causes teratogenicity and cardiotoxicity. The results showed that the toxicity effect of RGO/TiO2 is concentration dependent. The outcomes of present work contribute to the use of the RGO/TiO2 composites in nanomedicine.

Epizootic ulcerative syndrome (EUS), primarily caused by the water moldAphanomyces invadans,is an OIE-notifiable disease, having potential impacts on fisheries. We report EUS epizootics among estuarine fishes of Kerala, India, during 2018, under post-flood conditions 3 decades after its primary outbreak. Six fish species (Mugil cephalus,Platycephalussp.,Scatophagus argus, Ariussp.,Planiliza macrolepisandEpinephelus malabaricus) were infected, including the first confirmed natural case inE. malabaricusandP. macrolepis. Salinity, surface temperature, dissolved oxygen and pH of resident water during the epizootic were Aeromonas veronii,Shewanella putrefaciens,Vibrio vulnificusandV. parahaemolyticus) in tissues of affected fish indicates that EUS-infected fish may pose a public health hazard if not handled properly. Lack of clinical evidence in the region during the last 3 decades, a high number of affected fishes, including 2 new fish species, the severity of skin lesions and very low water salinity (A. invadans. Phylogenetic analysis based on the internal transcribed spacer region of the rRNA gene showed that the same clone of pathogen has spread across different continents regardless of fish species and ecotypes (fresh/estuarine environments). Altogether, the present study provides baseline data which can be applied in EUS management strategies within brackish-water ecosystems. We recommend strict surveillance and development of sound biosecurity measures against the disease.

Microplastic pollution and the impacts they generate on the marine ecosystem and its biota is a major global concern of recent decades. The present study was conducted to evaluate the spatio-temporal distribution of microplastics in the surface waters, sediments, and their subsequent ingestion by the commercially important fishes of Alappuzha Mud banks, a transient ecosystem formed in the littoral zones of the southwest coast of India exclusively during the Indian summer monsoon. Sampling conducted over three periods, Pre-mud bank (Pre-MB), Mud bank (MB), and Post mud bank (Post-MB) extending over three depths (2 m, 5 m and 18 m), along the semi-circular patch of mudbanks revealed marked spatio-temporal variability in microplastic distribution. In both surface water and sediments, microplastic concentration was comparatively high during MB than in Pre-MB and Post-MB periods. Spatially, during MB, the microplastic concentration was high at 5 m where the dampening of waves occurred concomitant to the thick fluid mud formation. In contrast, during Post-MB, with the subsequent dissipation of MB's and less wave dampening, the microplastics aggregated at 5 m were transported to both inshore (2 m) and offshore (18 m), thus raising their concentration at these depths. Likewise, the microplastic ingestion was more in fishes caught during MB (41%) than Post-MB (30%) and Pre-MB (29%) periods indicating increased uptake corresponding to the higher incidences in their ambient environment. Microplastic ingestion was more among pelagic planktivores, S. gibbosa (38%), A. chacunda (20%) and R. kanagurta (13%) compared to the demersal fishes. White coloured fragments of size 1–5 mm of polypropylene were the dominant microplastic in the surface waters, sediment and fishes analysed. The present study indicates the critical role of wind speed, rainfall, wave patterns, and the fluid muddy environment in regulating the microplastics distribution in a transient ecosystem formed along the southwest coast of India.

A study was conducted to evaluate the phytoplankton community structure and its relationship with selected physicochemical variables in the inshore waters of Tuticorin during January to December 2008. Water and plankton samples from the surface waters at two depths (5m and 10m) were collected on board the research vessel Cadalmin-IV. Standard methods were followed for phytoplankton identification, enumeration and estimation of physicochemical variables. The present study recorded 69 species of phytoplankton with 85.5% dominance of diatoms followed by 14.5% of dinoflagellates. The overall density of phytoplankton was comparatively higher at 10 m with a mean of 2.14x104 ±0.4x104 cells L-1 and 3.37x104 ±0.9x104 cells L-1 at 5 m and 10 m depth respectively. The analysis indicated that 10 m depth, especially during the monsoon season, is rich in diversity of algal species than at the same depth during post-monsoon. It is confirmed that the population density of phytoplankton is more influenced by seasonal fluctuation of the physicochemical variables especially due to the effect of northeast monsoon in the inshore waters of Tuticorin.

The stake net fishery of Panambukad in the main channel area of Vemband Lake, Kerala was studied during the first fortnight of August 2014. The observations indicated that the average catch including the marine debris ranged from 1.04 to 2.04 kg net-1 day-1 with an average of 1.34 kg net-1 day-1. The percentage of marine debris in the stake nets ranged from 42.68 to 73.4%. Plastic items formed 97% by weight and 99% by number of the total marine litter. The observed litter stuff was categorized as per UNEP system of classification of marine litter where, they are first identified based on their material composition (litter codeeg. PL) and then by their form (RL classes). Items found in the collection included plastic covers (PL07, RL15), metal cap (ME02, RL01), plastic bottle (PL02, RL02), fishing net (PL20, RL05), plastic cup and food containers (PL06, RL09), thermocol (FP 04, RL13), rubber sheet (RB05, RL28), plastic sacks (PL24, RL23), diaper (OT02, RL18) etc. Among them, plastic covers were most dominant and their average number and weight net-1 day-1 was 28 nos and 985 g respectively. The study also showed positive signs of decline in plastic bottles as a major litter item due to its targeted collection by recycling industry within a span of three years. In a survey conducted among the stake net fishers, there was consensus on the view that plastic litter in Vembanad Lake has increased during the last 10 years and this has affected the resources and the fishery. The stakeholders also expressed their willingness to pay for restoration of the fishery resources of the lake. The study recommends the need to establish proper solid waste management systems in coastal villages, to reduce the use of plastics, and provide facilities for disposal of litter which gets collected in stake nets and to increase the awareness among the public about the impacts of marine debris on ecosystem and resources.

Targeted drug delivery is an advanced method that increases the concentration of drug in the specific targeted area in the body. It improves efficacy of treatment and reduces the side effects in drug administration. The use of nanoparticles enhances the bioavailability, in vivo stability, intestinal absorption, solubility, sustained and targeted delivery. Quercetin (Q) is an anticancer agent used in cancer models due to its antioxidant and antitumor properties. Folic acid (FA) is the ligand used to activate receptor mediated endocytosis for targeted delivery of Quercetin. Polydopamine (PD) is pH sensitive and also inhibits angiogenesis. The quinones of PD serves as anchoring points for FA conjugation. In this work, honeycomb structured Nickel oxide (NiO) nanoparticles loaded with quercetin, surface modified with FA and PD was synthesized to target triple negative breast cancer cells. NiO was characterized by XRD, FTIR, Raman Spectroscopy, BET analysis and Zeta Potential. The honeycomb structure was confirmed by SEM. NiO size and morphology was analyzed by TEM. The porous structure of NiO enabled the efficient loading of Quercetin. Hemolysis analysis showed NiO has good hemocompatibility. The drug release profile confirmed a pH sensitive and controlled delivery of Quercetin. The drug release profile expressed higher release at lower pH. The drug release kinetic profile unveils the primary release mechanism to be diffusion controlled. MTT assay were performed against Vero cell line and MDA-MB-231 breast cancer cell line. The nanoformulation showed reduced cytotoxicity and good biocompatibility on Vero cells and appreciable anti-cancer activity on MDA-MB-231 breast cancer cell line.

Hydroxyapatite [Ca 10 (PO 4 ) 6 (OH) 2 , HAp] is commonly used for orthopaedic and dental implant applications, because it has been an attractive bioceramics for the bone regeneration. However, its poor mechanical strength and rheological properties gives a significant challenge to the application of the HAp for the replacement of load bearing implants. The present study reveals that HAp combines with various elements like Pristine HAp and HAp+ZrO 2 during wet chemical synthesis method. Further, there are possibilities to improve its mechanical strength and osseointegration with an added advantage of antibacterial activity. These synthesized materials were analyzed using X-ray diffractometer (XRD), field emission scanning electron microscope (FESEM) with energy-dispersive spectrometer (EDS) and fourier transform infrared spectroscopy (FTIR). The morphology of Pristine HAp is rod shape with length and width of 2.98μm and 3.32μm respectively. The HAp+ZrO 2 showed rice husk shaped morphology with the particle size ranging from 271.0 nm and 612.8 nm. The synthesized HAp+ZrO 2 composite could offer more mechanical stability to the implants than the pristine HAp.

Wound healing is a complex multistep process. Wound healing materials should have good antibacterial activity against wound infection causing microbes. Curcumin has effective antimicrobial activity, anti-inflammatory and antioxidant property. Titanium dioxide (TiO

Treating infection causing microorganisms is one of the major challenges in wound healing. These may gain resistance due to the overuse of conventional antibiotics. A promising technique is antimicrobial photodynamic therapy (aPDT) used to selectively cause damage to infectious pathogenic cells via generation of reactive oxygen species (ROS). We report on biocompatable nanomaterials that can serve as potential photosensitizers for aPDT. GO/Zn(Cu)O nanocomposite was synthesized by co-precipitation method. Graphene Oxide (GO) is known for its high surface to volume ratio, excellent surface functionality and enhanced antimicrobial property. ZnO nanoparticle induces the generation of reactive oxygen species (ROS) under light irradiation and it leads to recombination of electron-hole pair. Nanocomposites of GO and Cu doped ZnO increases visible light absorption and enhances the photocatalytic property. It generates more ROS and increases the bacterial inhibition. GO/Zn(Cu)O nanocomposite was tested against Staphylococcus aureus (S. aureus), Enterococcus faecium (E. faecium), Escherichia coli (E. coli), Salmonella typhi (S. typhi), Shigella flexneri (S. flexneri) and Pseudomonas aeruginosa (P. aeruginosa) by well diffusion method, growth curve, colony count, biofilm formation under both dark and visible light condition. Reactive Oxygen Species assay (ROS), Lactate dehydrogenase leakage (LDH) assay, Protein estimation assay and membrane integrity study proves the mechanism of inhibition of bacteria. Inhibition kinetics shows the sensitivity between bacteria and GO/Zn(Cu)O nanocomposite.

The inclusion complex formation between 2-hydroxy-1-naphthoic acid (2H1NA) and β-cyclodextrin (β-CD) in liquid, solid and virtual states was investigated. The binding constant of 2H1NA:β-CD complex is estimated in liquid state using cyclic voltammetry (CV) analysis at pH 2.75. Drastic increase in the anodic peak current and peak potential with the increase in β-CD concentration is attributed to the inclusion complex formation between β-CD and 2H1NA. The diffusion coefficient, and the electron transfer rate constant (ko) of the 2H1NA:β-CD complex are also estimated using CV studies. The solid 2H1NA:β-CD complex prepared by co-precipitation method is characterized by FTIR, and NMR techniques. The estimated stabilization energies, EHOMO-ELUMO, and MEP maps of complexes infer that guest molecule prefers the orientation in which it experiences lesser steric repulsion effect and scores as a highly stable and energetically favourable. Results of computational studies, semiempirical analysis and experimental investigations correlate well with each other.

Encapsulation of N-phenyl p-phenylenediamine (NPpPDA) into β-cyclodextrin (β-CD) has been investigated by various experimental techniques as well as theoretical methods. The results of PXRD, FT-IR, NMR and SEM analysis confirm the formation of inclusion complex. Significant change occurs in the fluorescence spectral intensity of inclusion complex during the addition of Fe2+ ion as compared to other metal ions. This indicates Fe2+ chemo-sensing ability of this host-guest complex. Geometrical optimization and stability of the structure have been carried out using density functional method (DFT/B3LYP) with 6-31g (d,p) basis set. The delocalisation energy of various types of bonding interactions were investigated by Natural bond orbital (NBO) analysis. Topological parameters for bonds of interacting atoms of complex C1 have been calculated and intramolecular interactions were analysed using Atoms in molecule (AIM) theory. Both experimental as well as theoretical methods suggest that the orientation 1 is more favourable structure among the proposed two orientations. NBO results confirms the presence of strong interactions between occupied orbitals of host and vacant orbitals of NPpPDA molecule which play a key role with respect to the stability of NPpPDA:β-CD complex.

Host–guest inclusion complexation of acetanilide (AA) into the β-cyclodextrin (β-CD) nano-hydrophobic cavity has been investigated using computational technique. Two different orientation of guest (AA) into host (β-CD) are considered for the inclusion of AA in to the nanocavity through the 2 o rim of β-CD. The energy differences in the inclusion process are calculated using PM3 semi-empirical method. By the investigation of stabilization energies, it is found that the “orientation 1” in which the benzene ring of AA oriented towards 2 o rim of β-CD nanocavity is the stable complex. The conclusions obtained from the computational analysis are in good correlation with the docking analysis.

is a serious problem occurring in ponds or estuaries where fish culture is practised. A possible solution to this problem is to raise oysters in an integrated culture with fish to improve water clarity and to help remove excess nutrients. In order to determine the effects that cultured oysters have on the environment, an experimental study was performed in the Moothakunnam region of the Vembanad lake in the Ernakulam District during February-November, 2012. The study was performed in four cages (1× 1× 1 m) referred to as treatments T1, T2, T3 and T4. The four treatments used fish ( Etroplus suratensis ) and oysters (Crassostrea madrasensis) in the ratio of 1:0.3, 1:0.5, 1:0.7 and 1:0 respectively. Several parameters were measured and compared between the four treatments, and these included temperature, pH, salinity, dissolved oxygen, biochemical oxygen demand, chemical oxygen demand, total suspended solids, ammonia, nitrite, nitrate and orthophosphate. Results showed that the parameters, DO, BOD, COD, TSS, ammonia and orthophosphate varied with different treatments and months. However, the contents of nitrite and nitrate showed variation only with respect to months. The eutrophication index (E) values calculated for the four treatments were 9.45 ± 4.41, 5.25 ± 3.23, 11.32 ± 6.17 and 11.52 ± 5.45 respectively. The lower E value obtained was for T2 which supports the conclusion that oysters can control eutrophication in an integrated aquaculture system. The optimal co-cultivation proportion of fish to oysters obtained from the present study was 1:0.5.

The supramolecular assembly of 1-hydroxy-2-naphthoic acid (1H2NA) with β-CD has been investigated by UV-visible and fluorescence spectroscopy. The stoichiometry and binding constant of inclusion complex was estimated using the Benesi–Hildebrand plot derived from the excitation and emission spectral data at 303 K. The estimated ΔG indicated that the inclusion is an exergonic and spontaneous process. The mechanism of complexation was investigated and confirmed by FTIR spectroscopy, semiempirical, and molecular docking studies. During the investigation of complexation, significant increase in the fluorescence intensity for the variation of β-CD concentration was observed. Based on this phenomena the chemosensory power of 1H2NA: β-CD complex was investigated thoroughly for various metal ions and we found the emission of complex showed a drastic increase in the intensity for Cr3+ and the fluorescence intensity enhanced to >50 out of all the metal ions studied. The order of change of fluorescence intensities fo...

The Indian marine environment, consisting of adjoining coastal areas and the exclusive economic zone (EEZ), directly sustains useful habitats and supports the livelihood of 3.9 million fishers. The average marine fisheries production of the country during the period 2010–2015 has been estimated at 3.36 million tons consisting of approximately 667 different fish species inhabiting the neritic zone that depend on the productivity of marine ecosystem and in turn are influenced by the reactive nitrogen (Nr) available in the system. During the past three decades significant advances have been made in industry, agriculture, fisheries, and other sectors and these have resulted in the release of Nr influencing the N-cycle in the coastal and marine ecosystems. Nitrogen assessment of the surface waters carried out in the EEZ and adjoining areas during the years 1998–2007 revealed that the annual concentrations (μM) of NO 2 ranged from 0 to 0.4, 0 to 0.6, and 0 to 0.7 in the Arabian Sea, Bay of Bengal, and Andaman Sea, respectively. The corresponding values for NO 3 (μM) were 0–2.5, 0–3, and 0–3.5, respectively. Nr transfer to the marine environment also influences eutrophication, algal blooms, changes in the ecological processes and habitats affecting ecosystem health. In this chapter, the present status of Nr assessment in the coastal and marine ecosystems in the country has been reviewed, its interaction with marine aquaculture listed, and the need for future research thrusts, especially on prediction of the extent and direction of impacts of altered nitrogen fluxes on the coastal and marine resources including diversity of faunal and floral community structure is discussed.

Practice of starter culture is an age old practice but without any scientific basis. With the awareness of need of microbial inoculations for regulation of fermentation process for quality production of desired quality foods innovative development have taken place. Development of new strains for elite strain which can improve the quality, stability, flavor, texture and phage resistant starter cultures are raised on a variety of medium depending organism as well as product to be developed. The starter culture are classified based on their composition growth requirement and methods of propagation. These starter cultures are preserved by different methods they can be available all the time. Though commercial strains are available their isolation and subsequent improvement through different genetical methods are desirable to get a novel strains with unique properties of commercial importance. Among different microorganisms such as lactic acid bacteria, yeast (Saccharomyce cerevisae, Penicillium camembertii, P. roquefortii) and Rhyzopus (R. oryzae, R. sojae) are extensively used for this purpose. Perfection in the preparation, storage and propagation need to be improved. Mixed starters with symbiotic activity have to be formulated.

An increasing number of deaths and injuries are reported in recent years for small children and physically challenged persons left in unattended parked vehicles when the surrounding air temperatures are warmer. Thermal abatement measures such as tinted windows and circulation fans have generally proved insufficient in reducing peak temperatures to a safe level. Due to prolonged time periods, the body temperature gets elevated so that injuries and deaths occurs for the children left alone in the vehicles . The solution for the problem is the design of a car safety seat using thermoelectric cooler that offers protection to the occupant temporarily. To maintain the temperature of the body for a limited time within acceptable range, thermoelectric cooling and forced air convection are featured by thermoelectric cooled seat. Thermoelectric cooling systems have been developed for the temperature control of sensitive electronic equipment, green applications and it is used to heat rejection. A seat occupant sensor and thermistor will detect an unsafe temperature rise for small child and activate the alarms and cooling systems. Thermoelectric coolers maintain the cabin air temperature up to 2hrs below the threshold in parked vehicles.