http://nopr.niscpr.res.in/handle/123456789/63492 2026-10-09T19:58:57Z http://nopr.niscpr.res.in/handle/123456789/63504 Title: Heavy metals contamination in coastal waters of South Vietnam Authors: Le, H P; Ho, V T; Le, T D; Nguyen, H T; Pham, H N; Tran, T L V; Trinh, D H N; Vu, T A; Nguyen, P U V; Dao, V H Abstract: The study was conducted to estimate the spatial and temporal variations, pollution levels, and potential sources of some heavy metals in the south coastal areas of Vietnam, using data obtained from the national monitoring stations from 2015 to 2021. The concentrations of As, Cr, Cu, Fe, Mn, Pb, and Zn in surface and bottom water samples at seven monitoring sites were analysed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) for heavy metal pollution indexing. Results indicated that concentrations of almost all the heavy metals (As, Cr, Cu, Pb, Mn, and Zn) were lower than the threshold limits. In exception, Fe concentrations were 1.0 – 12.8 fold higher than the standard level of seawater quality in Vietnam. The highest concentrations of Fe, Cu, Mn, Pb, and Zn were observed in Dinh An and Rach Gia sites, which may be due to the influence of strong discharges from local rivers. The Contamination Factor (CF) and Contamination Degree (CD) values were far below 1, indicating that the seawater in these sites is at a low contamination level. The principal component analysis indicated that heavy metal concentrations in Ganh Rai, Dinh An, Rach Gia, and Ha Tien sites might be affected by natural factors; while it might also be caused by anthropogenic activities in Nha Trang, Phan Thiet, and Song Doc sites. Page(s): 171-181 2024-02-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/63503 Title: Biodegradation of Low Density Polyethylene (LDPE) using marine bacteria isolated from tropical beaches of megacity Mumbai Authors: Fulke, A B; Khade, K; Sasidharan, A K Abstract: Plastics, although as useful and versatile as they are, have led to major environmental pollution. Its resistance to degradation has caused a major global threat to the environment. Plastic waste is disposed of in landfills causing soil pollution, incinerated releasing toxic fumes and causing air pollution, and dumped in the ocean causing a wide range of problems like entanglement and ingestion by marine creatures. Since the introduction of plastic, microorganism, though incapable of degrading it, is known to associate with its surface. Marine ecosystem is one such environment where the disposal of a large amount of plastic waste is found, and microorganisms are known to be associated with it. Hence, the marine environment can serve as a potential source for indigenous plastic-degrading microorganisms. In the following study, plastic pieces rooted deep in sediments from seven recreational beaches in Mumbai were collected for the isolation of possible plastic degrading bacteria associated with the surface of the collected plastic pieces. Altogether, nine isolates were isolated after three months of incubation of collected samples in a medium containing no carbon source. On identification by 16S rRNA sequencing, isolates were confirmed to be Pseudomonas, Bacillus and Lysinibacillus. The NCBI accession numbers were obtained for all the isolates. For further experimentation, only four Pseudomonas isolates (Strains ABFPD01, ABFPD02, ABFPD03 and ABFPD05) and one each isolate of Bacillus and Lysinibacillus were used. In the weight loss experiment, the ABFPD02 & ABFPD03 strains of Pseudomonas degraded 11 % of pre-weighed polyethylene strips in 2 months incubation period. The marine environment needs to be studied extensively for more potential microorganisms for plastic degradation. Page(s): 182-188 2024-02-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/63502 Title: Antibacterial activity and biogenesis of silver and zinc nanoparticles by Streptomyces sp. strain ANB 1 isolated from marine water of Port Blair, India Authors: Hassan, N; Kumari, A; Saha, P; Rao, K V Bhaskara Abstract: The uncontrolled and random misuse of commercial antibiotics has led to the ever-increasing rise in drug resistant bacteria. There is still a lag between the development of novel drugs and the emergence of drug resistant microorganisms. Thus, multi-drug resistant microorganisms pose a serious threat to the human race. The marine environment has a great biodiversity and is largely unexplored. It has proved to be an excellent source for isolating microorganisms that produce secondary metabolites with unique properties. In the present study, the focus was to appraise the hostile behavior of marine environment and isolate actinomycetes, which are capable of having antibacterial activity and also to synthesise metallic nanoparticles. Biogenic metal nanoparticles bear immense potential as an alternative to conventional antibiotics. Out of 15 actinobacterial isolates, ANB 1 identified as Streptomyces sp. strain ANB 1 showed the most efficient antagonistic activity against the clinical pathogens Klebsiella sp., Proteus sp., Escherichia coli, Pseudomonas sp. and Bacillus sp. The inhibition zones varied in diameter from 5 – 20 mm. Further, Streptomyces sp. strain ANB 1 successfully synthesised silver and zinc nanoparticles, which were characterised by the formation of characteristic peaks in the UV-Vis spectrophotometer. The nanoparticles thus produced bear immense potential as an alternative to treat multi-drug resistant pathogens. Page(s): 189-197 2024-02-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/63501 Title: Optimization of packing and transportation of the fingerlings of cobia (Rachycentron Canadum (Linnaeus, 1766)) and silver pompano (Trachinotus blochii (Lacepède, 1801)) Authors: Jayakumar, R; Tamilmani, G; Sakthivel, M; Rameshkumar, P; Anikuttan, K K; Sankar, M; Johnson, B; Rao, G H; Thomas, T; Krishnaveni, N; Moulitharan, N; Mercy, A A; Nazar, A K A Abstract: In mariculture, often the locations of fish hatcheries and farming are distantly situated, and hence, there is a need to transport the seeds/seedlings to a longer distance with maximum survival rate. In the present study, length and weight of fingerlings, duration of starvation, packing density, water volume, water temperature and oxygen level in the packing bags were standardized to ensure maximum survival during transportation. The cobia fingerlings with mean length and weight of 48±12 mm and 3.0±1.0 g, respectively were transported for a duration 48 h at 25 °C with 100 % survival at a packing density of 2.5 fingerlings per litre (L) (7.5±2.5 g/L). Similarly, silver pompano fingerlings with mean length and weight of 24±0.48 mm and 0.6±0.08 g, respectively were transported for a duration of 48 h at 25 °C with 100 % survival at a packing density of 18.75 fingerlings/L (11.25±1.9 g/L). Experiments on bulk transportation of pompano fingerlings in 1000 litres capacity HDPE tanks containing 600 litres of seawater with continuous aeration using oxygen cylinders fitted in a transportation vessel revealed that the silver pompano fingerlings can be transported for a duration of 48 h at 25 °C and 5 – 6 ppm dissolved oxygen concentration with 100 % survival at a packing density of 8.3 fingerlings/L (4.98±0.8 g/L). Page(s): 198-204 2024-02-01T00:00:00Z