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<title>DRS at CSIR-National Institute of Oceanography</title>
<link>https://drs.nio.res.in:443/drs</link>
<description>The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material.</description>
<pubDate xmlns="http://apache.org/cocoon/i18n/2.1">Mon, 13 Apr 2026 20:10:36 GMT</pubDate>
<dc:date>2026-04-13T20:10:36Z</dc:date>
<item>
<title>Phenanthrene-induced proteomic adaptations in marine Pseudomonas oleovorans: insights into PAH biodegradation mechanisms Available to Purchase</title>
<link>http://drs.nio.res.in/drs/handle/2264/9637</link>
<description>Phenanthrene-induced proteomic adaptations in marine Pseudomonas oleovorans: insights into PAH biodegradation mechanisms Available to Purchase
Bhatawadekar V.C; Damare S.R.
Environmental context Polycyclic aromatic hydrocarbons (PAHs) are toxic, persistent organic pollutants widely introduced into marine environments through oil spills, industrial effluents and incomplete combustion processes. Owing to their hydrophobic nature, PAHs readily accumulate in sediments and biota, posing serious ecological risks associated with their carcinogenic and mutagenic properties. In this study, we show that indigenous microbial assemblages contribute directly to PAH transformation in marine systems and underscore their relevance to intrinsic biogeochemical attenuation and environmentally compatible remediation approaches. Rationale Polycyclic aromatic hydrocarbons (PAHs) are persistent organic contaminants whose chemical stability and toxicity pose risks in marine environments. Phenanthrene (Phe) is used as a model PAH to elucidate transformation mechanisms relevant to more complex and carcinogenic compounds. Although microbial degradation of PAHs is recognised as a key attenuation process, chemically resolved evidence linking enzymatic activity to transformation intermediates in marine systems remains limited. This study investigates Phe degradation by a marine Pseudomonas oleovorans strain, integrating proteomic and metabolite analyses to resolve dominant degradation pathways. Methodology Pseudomonas oleovorans strain NIOSV8 was incubated in Luria�Bertani broth (LB) amended with Phe (100 mg L?1) for 48 h. Phe removal was quantified over time. Protein expression profiles under control and Phe-amended conditions were analysed using liquid chromatography�mass spectrometry (LC-MS) quadrupole time of flight (QToF)-based shotgun proteomics. Differentially expressed proteins were used to infer active metabolic pathways. Degradation intermediates were identified using gas chromatography�mass spectrometry (GC-MS) to validate proteomic interpretations. Results Approximately 55% of Phe was degraded within 48 h. Proteomic analysis identified 5902 proteins across all conditions, with 2486 proteins detected exclusively in Phe-amended cultures, indicating metabolic reprogramming. Enzymes associated with aromatic hydrocarbon transformation were enriched, particularly salicylate hydroxylase and catechol 2,3-dioxygenase-related proteins, consistent with a salicylate�catechol degradation sequence. Multiple oxidoreductases and dehydrogenases involved in xenobiotic metabolism were also upregulated. GC-MS analysis detected intermediates such as 1-naphthol and 8-methyl-1-naphthoic acid, which support the oxidative transformation of Phe to salicylate-related compounds. Discussion The combined proteomic and metabolite evidence demonstrates that Phe degradation proceeds by a salicylate-mediated pathway. The induction of oxidoreductases highlights oxidative reactions in PAH transformation and the maintenance of redox balance. Changes in energy metabolism indicate that Phe degradation is a metabolically demanding process. These findings provide mechanistic insight into microbial PAH transformation and contaminant fate in marine environments and sediments.
IF2024=2.3
</description>
<pubDate>Thu, 01 Jan 2026 00:00:00 GMT</pubDate>
<guid isPermaLink="false">http://drs.nio.res.in/drs/handle/2264/9637</guid>
<dc:date>2026-01-01T00:00:00Z</dc:date>
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<item>
<title>Copepod communities and trophic guilds: Patterns of structuring in tropical coastal waters off Southwest India</title>
<link>http://drs.nio.res.in/drs/handle/2264/9633</link>
<description>Copepod communities and trophic guilds: Patterns of structuring in tropical coastal waters off Southwest India
Swetha, R. A.; Madhu, N.V.; Praveena, S.; Muraleedharan, K.R.; Mohammed,H.S. E.; Jithin P.E.; Arya,K.S.
Monthly investigations conducted during 2020 - 2021 in the nearshore waters (NSW; &lt;30?m depth) off Cochin and the Cochin Estuary (CE), along the southwest coast of India, aimed to elucidate the dynamics of mesozooplankton (MZ) community, with particular emphasis on copepod assemblages. Despite their close geographical proximity, the two systems exhibited pronounced differences in hydrographic regimes and biological responses. The CE, a tropical microtidal estuary, shaped by diurnal tidal oscillations and monsoonal river discharge, exhibited highly dynamic hydrography, while the NSW remained relatively stable although under the influence of seasonally occurring coastal upwelling, freshwater influx, and large-scale circulation in the eastern Arabian Sea. These contrasting forcings were reflected in phytoplankton growth patterns, with the CE sustaining higher but more variable chlorophyll a concentrations (6.16?�?5.22?mg?m?3) compared to the NSW (1.29?�?1.14?mg?m?3). Correspondingly, MZ biomass and abundance in the CE showed strong temporal variability, including a marked decline during the summer monsoon (SM) driven by freshwater influx, stratification, and salinity dilution. Copepods consistently dominated both the MZ communities in both systems (80% of total MZ), emphasizing their ecological resilience and trophodynamic significance. Bestiolina similis was a persistent and characteristic copepod in the NSW, regardless of season, reflecting its affinity for euhaline conditions, but its abundance declined in the CE during the SM period, indicating an intolerance to mesohaline environments. In contrast, during winter monsoon (WM) and spring inter monsoon (SIM), both systems supported higher abundance of euhaline copepod taxa such as Canthocalanus pauper, Nannocalanus minor and Corycaeus catus. Feeding guild analysis further revealed a sustained predominance of herbivorous copepods, particularly B. similis and Acrocalanus spp., in both enviornments, closely coupled with phytoplankton availability. Omnivorous and carnivorous copepods appeared episodically, especially in the NSW, where their dynamics were largely modulated by transient hydrographic fluctuations and prey variability.
IF2024=2.6
</description>
<pubDate>Thu, 01 Jan 2026 00:00:00 GMT</pubDate>
<guid isPermaLink="false">http://drs.nio.res.in/drs/handle/2264/9633</guid>
<dc:date>2026-01-01T00:00:00Z</dc:date>
</item>
<item>
<title>Thermal desiccation and expression of HSP90 and osmotic avoidance protein genes in an acorn barnacle, Amphibalanus amphitrite</title>
<link>http://drs.nio.res.in/drs/handle/2264/9631</link>
<description>Thermal desiccation and expression of HSP90 and osmotic avoidance protein genes in an acorn barnacle, Amphibalanus amphitrite
Sekhar, B.; Desai,D.V.
The marine intertidal zone (IZ) is ideal for deciphering the organisms� response to thermally desiccated stress during tidal emersion. The distribution of organisms across horizontal and vertical transects is plasticity of thermal adaptation potential. The acorn barnacle, Amphibalanus amphitrite inhabits the upper and mid rocky intertidal zone, often encountering episodic thermal desiccation during inter-tidal emersion. In order to survive, the desiccated organisms endure the heating effect of the rocky substratum and aerial temperature, which leads to body temperature perturbation, coma response, and differential gene expression. The intraday thermal desiccation stress response in A. amphitrite has not been studied in a way that integrates both ecological and molecular responses under natural conditions. This study observed and experimented the various factors in an intraday of monsoon environment, including aerial and substratum temperature, duration of emersion along with ecological responses such as coma response, and gene expression. This is the first study to design and standardise the primer for the gene Osmotic Avoidance protein (OA). The expression of stress genes, heat shock protein 90 (HSP90) and Osmotic Avoidance protein (OA) were carried out using Real-time qPCR among thermally desiccated Amphibalanus amphitrite inhabiting the intertidal zone of Anjuna, Goa, India. The ecological responses revealed compelling insights into the effects of thermal desiccation on barnacles. After a 4�h of exposure, a slight increase in body temperature from 30.5��C to 31��C triggered a staggering 50% increase in coma response among the barnacles. The study highlights the dynamic expression levels of HSP90 and OA, which fluctuated significantly with varying degrees of thermal and desiccation stress. Notably, we observed a sharp increase in the combined expression of HSP90 and OA after 4�h, followed by a temporary decrease at 6�h and a HSP90 resurgence at 8�h where the body temperature was the lowest. Such an upregulation of HSP90 suggests temperature-independent and prolonged aerial exposure-mediated regulation of gene expression. Moreover, the declining expression of OA from the 4th to the 8th h of aerial exposure underscores an impressive molecular regulation, suggesting an establishment of osmotolerance among the desiccated barnacles. This research underscores the resilience and adaptability of barnacles, emphasising the need for continued study in the face of climate variability. Expression patterns of HSP90 and OA provide concrete evidence of the existence of thermal and desiccation stress and tolerance mechanisms among A. amphitrite in the IZ.
IF2024=3.2
</description>
<pubDate>Thu, 01 Jan 2026 00:00:00 GMT</pubDate>
<guid isPermaLink="false">http://drs.nio.res.in/drs/handle/2264/9631</guid>
<dc:date>2026-01-01T00:00:00Z</dc:date>
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<item>
<title>Assessment of macroplastic and microplastic pollution in the beach sediments along the Murud, central west coast of India</title>
<link>http://drs.nio.res.in/drs/handle/2264/9632</link>
<description>Assessment of macroplastic and microplastic pollution in the beach sediments along the Murud, central west coast of India
Behera,A.K.; Ramadoss, D.; Kolandhasamy,P.; Subramanyam B.A.
Plastic pollution has emerged as one of the most pressing threats to marine ecosystems, particularly along densely populated and tourism-driven coasts. This study provides the first integrated assessment of macro- and microplastic pollution along the Murud coastline, Maharashtra, India, an ecologically sensitive region that hosts Olive Ridley turtle nesting grounds and migratory seabird roosting sites. Macroplastic litter was quantified through standardised video transects, while sediment samples from shoreline, mangrove, estuarine, and offshore habitats were analysed for microplastics using density separation, microscopy, and Raman spectroscopy. Results revealed high macroplastic loads across all surveyed beaches, dominated by food wrappers, single-use polybags, plastic cups, and discarded fishing gear. Based on Clean Coast Index (CCI) values, beaches were classified as either clean or dirty, with MSS 3 and MSS 4 identified as the most affected sites due to intensive household dumping and tourism pressure. Microplastics were abundant in estuarine sediments (up to 6���1.8 items g?1), with fibres as the dominant type, followed by fragments and films. Blue and transparent particles were most common, linked to fishing gear and packaging. Raman analysis identified polyethylene (PE) and polypropylene (PP) as the major polymers, along with polyester, nylon, and poly(acrylamide) from textiles and domestic waste. Risk indices indicated localised high potential ecological threats, particularly from hazardous polymers, despite relatively moderate overall pollution levels. The findings highlight the vulnerability of Murud's coastal ecosystem to plastic pollution indicating potential risk to endangered turtles, migratory birds, and associated biodiversity. Effective management strategies, including improved waste disposal, community-based awareness, and regulation of tourist activities, are urgently required to mitigate further degradation and preserve the ecological and economic value of this coastal hotspot.
IF2024=4.9
</description>
<pubDate>Thu, 01 Jan 2026 00:00:00 GMT</pubDate>
<guid isPermaLink="false">http://drs.nio.res.in/drs/handle/2264/9632</guid>
<dc:date>2026-01-01T00:00:00Z</dc:date>
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