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Understanding fish reproduction biology, particularly sexual maturity, the reproductive cycle, and fecundity, is useful for managing fisheries. The reproduction of Giuris margaritaceus in Limboto Lake is regrettably unknown. Over a year, fish specimens (N = 662) were gathered. They ranged in length from 6.5 to 20.9 cm (mean SD 10.9±2.5). Fecundity varied from 30,057 to 61,920. The first sexual maturity of male and female fish occurred at different sizes, 11.2 cm and 10.3 cm, respectively. This information is needed to determine this fish's lowest acceptable harvest length under the management aim to enter all-female fish for reproduction at least once. We estimated the reproductive of G. margaritaceus cycle using the size of the oocytes, histological analysis of the ovaries, and monthly mean GSI. These techniques produced the same reliable conclusion: G. margaritaceus can spawn yearly, with maximal between September and October. Based on this finding, spawners of G. margaritaceus can be kept from entering the reproductive stock between September and October. Future efforts to fine-tune fishing efforts for the effective management of G. margaritaceus may be aided by the study's findings. [ABSTRACT FROM AUTHOR]

Local communities have extensively utilized different components of mangrove (Sonneratia caseolaris) plants in traditional medicine. These plants are known for their secondary metabolites, including steroids, triterpenoids, saponins, and flavonoids. S. caseolaris grows in Ujung Pangkah waters in Gresik, East Java, Indonesia, and is known for its proximity to environmental waste. It is believed that environmental factors at this site may contribute to the presence of characteristic bioactive compounds in the plant. In this study, the toxicity, bioactive constituents, and pharmacokinetic potentials of the aqueous extracts of the leaves of S. caseolaris were investigated. S. caseolaris leaves were extracted with methanol, distilled water, and three mineral water products produced and distributed in Indonesia. The toxicity of the aqueous S. caseolaris leaf extracts was tested by determining the LC50 using Artemia salina Leach and a 2,5-diphenyl-2H-tetrazolium bromide (MTT) assay with TIG-1-20 lung fibroblasts. None of the aqueous S. caseolaris leaf extracts were categorized as toxic substances based on the LC50 and MTT assays. The six compounds detected by liquid chromatography high-resolution mass spectrometry (LC–HRMS) in a previous study were analyzed using quantitative structure-activity relationship (QSAR) and absorption, distribution, metabolism, excretion, and toxicity (ADMET) methods. Bis(3,5,5- trimethylhexyl) phthalate and bis(2-ethylhexyl) phthalate were identified as component from S. caesolaris and are known plasticizers. These compounds were suspected to be carcinogenic substances based on QSAR and ADMET analyses, indicating that the environment of S. caseolaris may be a site of plastic waste. [ABSTRACT FROM AUTHOR]

Intraspecific sexual dimorphism between males and females is tied to sexual selection, such as body features and color patterns. Sexual selection pressure in the genus Giuris may occur in either or both sexes. The present study aimed to analyze the sexual dimorphism of Hulu'u fish (Giuris sp. Limboto) from Limboto Lake, Gorontalo Province, North Sulawesi. 272 individuals of Giuris sp. from Lake Limboto, were used with a male to female ratio of 1:1. The mean total length (TL) of male and female fish was 11.5± 2.1 and 12.2± 2.8cm, respectively. A total of 17 morphometric characters were analyzed using the morphometric truss method (dividing using TL) and analyzed by Z-test. Characters with significant differences between males and females were then analyzed using principal component analysis (PCA). The study found that male fish have longer fin sizes than females, including the length of the first dorsal, pectoral, pelvic, anal and caudal fin. In addition, male fish have longer heads than female fish. PCA analysis of the first principal component (C1) consisted of several characteristics: the length of the first dorsal, pectoral, and caudal fin length. The characteristics of head length, pelvic fin length, and anal fin length are associated with the second principal component (C2). The first and second main components could explain 78.3% of the data diversity. Furthermore, the male individuals had a conical genital papillae shape, contrasting with female individuals with bulbous genital papillae shape. In conclusion, males and females of Giuris sp. from Lake Limboto can be distinguished by their fins, heads, and papillae. [ABSTRACT FROM AUTHOR]

Diabetic and cancer, as an examples of degenerative diseases in human may arise as consequences of free radicals, i.e. highly reactive molecules. The reactiveness of free radicals can be constrained by a substance, known as antioxidant. Mangroves that inhabitant of highly dynamic waters of estuary is likely have defend activity by produce some substances those known as bioactive compounds that may have potency of antioxidant. The quality and quantity of bioactive compounds may affected by extraction method. This study aims to evaluate antioxidant potency of Sonneratia caseolaris leaf with three diferent length time (24, 48 and 72 hours) of maceration by applying of DPPD (1,1-diphenyl-β-picryl hydrazyl) method. Result based on 50% of inhibition concentration (IC50) value suggest that the best maceration time is 24 hours (IC50 was 6.35 ppm), following by 72 and 48 hours (IC50 were 11.5 and 17.4 ppm, respectively). In addition, overall of different maceration time show IC value lowe than 50 ppm, indicate that Sonneatia caseolaris leaf have very strong potential of antioxidant activity.

Oceanographic factor influences the number of fish catch in Bali Strait, in which global phenomena such as El-Nino Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD) also have a role in influencing the migration of fish. This research aims to analysis annual variation of Sea Surface Temperature (SST) and Sea Surface Chlorophyll-a (SSC) in Bali Strait, and its effect on fish catch. The method applied a quantitative descriptive with correlation analysis and spatial analysis using Geographical Information System. The analysis described a significant impact of oceanographic parameters on pelagic fish catch. SST described a negative correlation, in which the higher the SST, the lower the catch and vice versa. There was a time lag between SST and catch when the upwelling process occurs which was followed by an increase in SSC concentration and catch. SSC has a significant impact on the number of fish catch which describes a positive correlation, and it illustrated a time interval between the highest concentration of SSC and the period of fishing peak season. The intensity of upwelling refers to the variability of SST by physical and dynamic processes of water, which also affected by the ENSO and the Indian Ocean Dipole IOD. [ABSTRACT FROM AUTHOR]

Corals in the genus Porites are among the most dominant scleractinian corals in the coral reef ecosystems yet highly vulnerable to climate change impacts and diseases. In the Kondang Merak and Sempu Strait waters of Indian Ocean, it has been reported that more than 45% of the corals were infected with Pink Line Syndrome (PLS). The objectives of this study are to isolate, morphologically and molecularly characterize, and identify the PLS associated bacteria that infected Porites lutea coral. The sampling was performed at the Kondang Merak waters in June 2018 by snorkeling during low tide. In order to isolate and purify the dominant bacterial colony, quadrants streak-plating technique was performed using ZoBell marine agar culture media. 16S rRNA sequencing and BLAST homology were performed for the molecular identification of the bacterial colony. Results showed that the bacterial colony associated with PLS was of Bacillus cereus, which was closely related to Bacillus pseudomycoides, Bacillus toyonensis and Bacillus thuringensis with 97% similarity. The occurrence of B. cereus bacterium in the PLS infected P. lutea demonstrated that this opportunistic pathogen might be responsible for the PLS in the P. lutea coral. [ABSTRACT FROM AUTHOR]

Oil spillage accidents can cause severe short-term effects to marine organisms and may lead to devastating long-term impact to marine environments. This study determined the influence of water accommodated fractions (WAFs) of diesel oil, chemically enhanced WAFs (CEWAFs) of diesel oil and oil dispersant (IPAC-OCD) to the toxicity of green algae, Tetraselmis chuii, and marine diatom, Chaetocheros calcitrans. Both the phytoplankton species were exposed to different concentrations of WAFs, CEWAFs and dispersant (0%, 5%, 10%, 20%, 40%, 80%). All of the toxicants significantly reduced the growth of phytoplankton, however, the level of response varied by solution and species. The dispersant has the highest impact among all the chemicals studied. The dispersant is very highly toxic to C. calcitrans, but still practically non-toxic to T. chuii. Even though, WAFs have higher impact to T. chuii than C. calcitrans, the chemicals are practically non-toxic to both phytoplankton species and, moreover, in short-term exposure, low concentration of WAFs may stimulate the growth of C. calcitrans. However, the mixture of diesel oil WAFs and dispersant cause synergistic toxicity to C. calcitrans that increases the WAFs toxicity. This finding implies that the dispersant application to mitigate the oil spills may negatively impact the marine phytoplankton. [ABSTRACT FROM AUTHOR]