Aquatic Life Sciences

Nur Afidatul Himma

Parasitic infections in marine fish pose economic and public health risks, particularly when zoonotic species are involved. Ribbonfish (Trichiurus lepturus), a commercially important species in Indonesia, is highly susceptible to endoparasites that may reduce fish quality and threaten human consumers. This study aimed to identify the types, prevalence, and intensity of endoparasites infecting ribbonfish landed at Paciran (Lamongan) and Tamperan (Pacitan). A total of 56 fish samples were examined through necropsy and microscopic observation of internal organs. Two nematode species, Anisakis sp. and Camallanus sp., were detected in the intestine, stomach, and muscle tissues. Prevalence was 0.2% at Paciran and 0.4% at Tamperan, while intensity reached 1.3 and 1.9 ind/individual, respectively. Infected fish were typically larger, with body weights ranging from 100–400 g and lengths of 60–80 cm, and often contained undigested small fish and crustaceans that may serve as intermediate hosts. Although infection levels were classified as low, the detection of zoonotic Anisakis sp. underscores the need for continued monitoring to prevent potential health risks and safeguard fishery resources.

Aquatic Life Sciences

Muh Yusril AL Tulus, Diana Maulianawati

Shrimp aquaculture depends on stable water quality, but fluctuations often reduce growth and survival, making optimal conditions essential for sustainable Penaeus monodon culture. This study aimed to evaluate key water quality parameters in two shrimp ponds and assess their suitability against established aquaculture standards. Field measurements and laboratory analyses were conducted over ten weeks across three sampling stations in each pond. Parameters measured included pH, temperature, salinity, dissolved oxygen (DO), nitrate, nitrite, ammonia, phosphate, and water hardness. Results showed that pH ranged from 7.29–7.80, temperature from 31.40–32.00 °C, salinity from 17.30–17.88 ppt, and DO from 5.29–5.87 mg/L, all within acceptable limits (SNI 8038.1:2014). Nutrient concentrations varied, with nitrate (0–0.4 mg/L), nitrite (0–0.4 mg/L), ammonia (0.1–0.4 mg/L), and phosphate (0–0.5 mg/L), where ammonia occasionally exceeded the safe threshold of 0.1 mg/L. Water hardness ranged from 0.17–0.43 mg/L CaCO₃, below the reference limit of 100 mg/L CaCO₃. Overall, the ponds provided suitable conditions for shrimp growth, but elevated nutrient levels at certain periods indicate the need for improved feed and waste management. Maintaining balanced water quality is essential to optimizing shrimp health, enhancing productivity, and ensuring the sustainability of aquaculture practices.

Aquatic Life Sciences

Zahrina Hibatul Azizah

Bacterial infections caused by Aeromonas hydrophila are a major problem in freshwater aquaculture, often leading to high mortality and economic losses. Plant-based alternatives are needed to reduce dependence on synthetic antibiotics and mitigate antimicrobial resistance. This study evaluated the therapeutic efficacy of Crinum asiaticum leaf extract against A. hydrophila infection in juvenile common carp (Cyprinus carpio; 7–9 cm, ±80 g). Fish were immersed in extract solutions at concentrations of 20 mL (P1), 40 mL (P2), and 60 mL (P3) per 36 L of water for a single 45-minute treatment. The experiment followed a Completely Randomized Design (CRD) with three treatments and three replicates. Clinical signs, feeding response, startle reflex, survival rate, and water quality were monitored for 14 days. More than half of the infected fish developed dropsy, exophthalmia, and hemorrhages within 72 hours. Fish treated with 20 mL extract recovered fastest, achieving complete lesion resolution and a 90% survival rate. In contrast, P2 and P3 showed prolonged symptoms and only 10% survival, likely due to physiological stress and mild toxicity caused by higher concentrations that may irritate gill tissues. Water quality remained within optimal ranges throughout the trial. The superior therapeutic performance of the 20 mL concentration is likely attributable to the synergistic action of alkaloids and flavonoids at moderate levels, which enhance antimicrobial activity without inducing stress. These findings indicate that 20 mL is the most effective and safest concentration for immersion therapy, reinforcing the potential of C. asiaticum as a natural treatment for sustainable freshwater aquaculture.

Aquatic Life Sciences

Abduljaleel K, P S Prakash, Manjula KT, Mini PV

Mangrove ecosystems, distributed across tropical and subtropical coastlines, are globally recognized for their exceptional biodiversity and multifunctional ecological roles. They sustain coastal fisheries by serving as breeding and nursery habitats, support diverse terrestrial and aquatic fauna, enhance shoreline stability through wave attenuation and erosion control, and improve water quality via nutrient recycling and pollutant filtration. Mangroves are also among the most efficient blue carbon sinks, contributing significantly to climate-change mitigation. From a socio-economic perspective, they provide timber and non-timber resources, support artisanal fisheries, enable ecotourism-based livelihoods, and hold high potential for carbon-credit revenue and bioprospecting. The review synthesizes evidence from 135 studies published between 1990 and 2024, retrieved from Web of Science, Scopus, Google Scholar, and institutional repositories, based on their relevance to mangrove ecology, ecosystem services, and community-level economic benefits. Only peer-reviewed articles, technical reports, and case studies with clear methodological descriptions were included. The synthesis reveals that the ecological and economic functions of mangroves are strongly interdependent, with degradation of habitat quality directly reducing fisheries productivity, carbon storage efficiency, and livelihood security. The review highlights the urgent need for integrated management approaches, including hydrological restoration, community-based conservation, and policy-supported payment-for-ecosystem-services mechanisms, to enhance ecosystem resilience under accelerating anthropogenic and climate pressures.

Aquatic Life Sciences

Erlando Fatiranes, Santhy Wisuda Sidauruk, Bustari Hasan

Fish stomach is a by-product of the fishing industry that has potential as a natural source of pepsin enzyme, particularly from catfish (Clarias sp.). This study aimed to characterize crude pepsin extracted from catfish stomachs. The extraction was carried out by homogenizing the stomach with 10 mM Tris-HCl buffer (pH 7.5), followed by centrifugation at 10,000 g for 15 min at 4°C. The obtained pepsinogen was activated using 3 N HCl at pH 2 and neutralized to pH 2.75 with 2 N NaHCO₃. Enzyme activity was determined using the hemoglobin assay at 280 nm, and protein concentration was measured by the Bradford method at 595 nm. The crude pepsin showed an activity of 33.50 ± 0.87 U/mL, protein concentration of 0.358 ± 0.005 mg/mL, total activity of 1,608 ± 41.57 U, and specific activity of 93.52 U/mg. The enzyme exhibited optimal activity at 50°C and pH 4, with relative activity toward NaCl, ZnCl₂, and FeCl₃ of 81.08%, 49.10%, and 128.15%, respectively, indicating Fe³⁺ acted as an activator. These results demonstrate that catfish stomachs can serve as a potential halal-compatible pepsin source, supporting enzymology advancement and fish waste valorization.

Aquatic Life Sciences