The length-weight relationship and the relative condition factor of yellowfin tuna Thunnus albacares collected on the Parangipettai coast, southeast coast of India was studied. Logarithmic equations did not show any significant difference in the regression coefficient for males, females, and indeterminates of T. albacares. The exponent ‘b’ values were less than 3 (b > 3) and expressed as 2.78 for males, 2.82 for females, and 1.79 for indeterminates. The relative condition factor (Kn) decreased with the increasing of fork length, which showed seasonal fluctuations during the study period. The Kn values were found to be higher in the post-monsoon than in pre-monsoon season. The Kn value obtained from the present study is 1, which indicates a good health condition of fish, while the values less than 1 predict an unhealthy condition of fish. The Kn values fluctuated between 0.97 and 1.60 for both sexes, and it is clearly evident that the health condition of T. albacares caught along the Parangipettai coast is good and the site is a good environment for their survival.

Members of the pennellid genus Lernaeenicus Lesueur, 1824 (Copepoda, Siphonostomatoida) have frequently been recorded from commercially important fishes collected along the coasts of India. Marine fish hosts from landing centres at Nagapattinam and Parangipettai Tamil Nadu, southeast coast of India, were examined for parasitic copepods between January 2011 and December 2013. A total of nine species including three unidentified species of Lernaeenicus were recorded: (1) L. alatus Rangnekar, 1962 from the Indo-Pacific king mackerel Scomberomorus guttatus (Bloch & Schneider, 1801), (2) L. anchoviellae Sebastian & George, 1964 from the golden trevally Gnathanodon speciosus (Forsskål, 1775), (3) L. hemirhamphi Kirtisinghe, 1932 from the blue-barred halfbeak Hemiramphus far (Forsskål, 1775), Lutke’s halfbeak H. lutkei Valenciennes in Cuvier & Valenciennes, 1847a and the ribbon halfbeak Euleptorhamphus viridis (van Hasselt, 1823b), (4) L. polynemi Bassett-Smith, 1898 from the fourfinger threadfin Eleutheronema tetradactylum (Shaw, 1804), (5) L. seeri Kirtisinghe, 1934 from the wahoo Acanthocybium solandri (Cuvier in Cuvier & Valenciennes, 1832), (6) L. stromatei Gnanamuthu, 1953 from the black pomfret Parastromateus niger (Bloch, 1795), (7) Lernaeenicus sp. 1 from the Indian anchovy Stolephorus indicus (van Hasselt, 1823a) and the rainbow sardine Dussumieria acuta Valenciennes in Cuvier & Valenciennes, 1847b, (8) Lernaeenicus sp. 2 from the goldspot mullet Chelon parsia (Hamilton, 1822), and (9) Lernaeenicus sp. 3 from the flathead grey mullet Mugil cephalus Linnaeus, 1758. Four pennellid species (L. hemirhamphi, L. polynemi, L. seeri and L. stromatei) were studied for their seasonal occurrence including prevalence and mean intensity, both of which were high in postmonsoon (2011) and low in premonsoon (2013) seasons. A checklist is provided for the Indian species of Lernaeenicus.

Elicitors are the agents that stimulate the defense responses of plants, and accumulate specialized metabolites in plant tissue culture. This study investigated the elicitor-feeding response of H. pinifolia suspension cell cultures (SCC) for metabolomics analysis and screening of specialized compounds against Candida albicans. Methyl jasmonate (MeJA) was used as an elicitor, and treatment of SCC at a concentration of 20 µM MeJA resulted in the maximum rosmarinic acid (RA) accumulation (117 mg/g dry weight), with transcript levels of RA biosynthetic genes HpPAL, HpC4H, and Hp4CL being 4.2, 2.5, and 3.7-fold higher, respectively, than the controls. GC-MS-based metabolomics analysis revealed a total of 47 metabolites, including 30 organic acids, six amino acids, six flavonoids, two sugars, two plant growth regulators, and one vitamin, which were significantly different between control and MeJA-treated cells. Furthermore, five phenolic acids were discovered at higher concentrations, including p-anisic acid, p-coumaric acid, caffeic acid, vanillic acid, and rosmarinic acid, and were purified and structurally elucidated for alternative antifungal screening against C. albicans and the evaluation of ADMET properties. The results from antifungal screening revealed that RA at MIC of 31.25 mg/L exhibited the lowest growth percentage of C. albicans (1.99%), with higher inhibition of isocitrate lyase 1 (ICL 1) enzyme (93.1%), followed by p-anisic acid (86.2%) and caffeic acid (85.1%), respectively. The drug likeliness and ADMET properties of RA exhibited promising results, with a bioactivity score of 0.57, 0.15, and 0.24 for nuclear receptor ligand, protease inhibitor, and enzyme inhibitor, respectively. Therefore, MeJA appears to have a significant effect on enhanced RA accumulation in H. pinifoia cells with phenylpropanoid transcript expression, and acts as an ICL1 inhibitor of C. albicans.

A new sandperch is described from 3 specimens from off Parangipettai, southeastern India. It can be separated from its congeners in having a combination of dorsal-fin rays V, 21‒22; anal-fin rays I, 17‒18; pectoral-fin rays 17‒18; pored lateral-line scales 53‒54; median predorsal scales 7; transverse scale rows 4/13; gill rakers on 1st gill arch 15‒17; single row of stout teeth on vomer; no teeth on palatine; 3 pairs of enlarged canines at front of lower jaw; opercle uniformly dark brownish; blade-like patch on cheek, the patch orange dorsally and reddish ventrally, fading entirely in preservative; dorsal fins light grayish with 2 rows of spots; a whitish longitudinal band just above lateral axis of body; dorsal surface of body with 8 irregular blackish saddles and lower half with 7 reddish bars and black dots on upper half of each bar; lower half of anal fin reddish; caudal fin grayish with upper and lower portion darker and vertical rows of orange dots on yellowish bands. The new species is most similar to Parapercis somaliensis and Parapercis kentingensis morphologically and genetically, but differs in coloration, serrations on the opercle, and body proportions. The establishment of the new species is also supported by DNA barcoding analysis.

The study assessed the seasonal and inter-annual variability of new production in the northern Indian Ocean (NIO) utilizing MODIS-Aqua satellite data during 2011–2020. The generated new production images are based on sea surface temperature (SST) and chlorophyll-a data, processed and analysed using the developed and validated empirical algorithm using in-situ datasets. The analysis focused on the Arabian Sea (AS) and Bay of Bengal (BoB), examining the seasonal changes. Data processing involved two approaches: first, using only SST, and second, incorporating chlorophyll-a data along with SST. The findings reveal higher new production uptake in the northern region during the winter, contrasting with the southern region, where uptake rates peak in the summer. Both AS and BoB generally exhibit lower productivity in the spring. The AS exhibits greater productivity than the BoB. This is mainly due to higher production in the summer (1.8 µmol N m⁻²d⁻¹) and winter (1.7 µmol N m⁻²d⁻¹), along with stronger downward fluxes associated with the deep mixed layer.