Peptides with angiotensin-I converting enzyme (ACE) inhibitory activity have received considerable interest due to their potential as antihypertensive agents and consumer concern over the safety of synthetic drugs. The objective of this study was to isolate ACE inhibitory (ACEI) peptides from Caulerpa lentillifera (known commonly as sea grape) protein hydrolysate. In this study, short-chain peptides were obtained after hydrolysis by various enzymes and subsequently by ultrafiltration. Thermolysin hydrolysate showed the highest ACEI activity. Bioassay-guided fractionation was performed using reversed-phase high performance liquid chromatography (RP-HPLC) to uncover the fraction 9 with the highest ACE inhibitory activity from thermolysin hydrolysate. Peptides in this fraction were further identified using liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis coupled with de novo sequencing, which gave two oligopeptides, FDGIP (FP-5) and AIDPVRA (AA-7). The identities and activities of these two peptides were further confirmed using synthetic peptides. Their IC50 values were determined as 58.89 ± 0.68 µM and 65.76 ± 0.92 µM, respectively. Moreover, the inhibition kinetics revealed that both FP-5 and AA-7 are competitive inhibitors. These activities were further explained using molecular docking simulation. The present study is the first report about ACEI peptides derived from Caulerpa lentillifera and it shows the potential for preventing hypertension and for functional food development.

Kopasanda (Chromolaena odorata L.) R.M King and H. Rob were classified as blossoming bush species in the Asteraceae family. An empirical study showed that kopasanda (C. odorata L.) leaf had been used by the embankment farmers at South Sulawesi Province to eradicate Vibriosis which caused death for tiger prawn (P.monodon Fabr.). The objective of research was to understand the bioactive compound that was contained within kopasanda (C. odorata L.) leaf extract and its antibacterial activity against V. harveyi. Result of

Shrimp, Penaeus monodon (Fabricius) and Penaeus merguiensis (de Man), culture on East Java is described with special attention to the differences in production characteristics between areas and districts. Traditionally, tambak culture developed along the North coast of East Java where the majority of modern tambaks are still located. The practice never developed extensively on Madura's Island. With the exception of the latter, intensification, startingin 1984‐1987, touched all areas. In 1991, the combined production of P monodon and P. merguiensis reached 35 000 Mt, representing a value of US$ 220 × 106. The following year, a decline in total production was noted, mainly caused by a diminished production of intensive farms. Possible causes for this production drop are explored.

Dunaliella salina is a type of marine microalgae. The objective of this research were investigated the effect of D. salina to inhibit the growth of E. tarda. The method used in this study was examined antibacterial activity of D. salina using disc diffusion and co culture test. The secondary metabolite compound in D. salina was tested using phytochemical screening and FTIR methods. The results obtained D. salina extracted using n-hexane showed the best activity for inhibiting the growth of E. tarda. Minimum concentration of 100 mg.L -1 crude extract can inhibit E. tarda with a total of bacterial colonies 137x10 11 CFU.mL -1 . The phytochemical test results showed that D. salina extract using n-hexane contained flavonoids, saponins, alkaloids, terpenoids and phenols. The FTIR analysis showed phenol and carotene compounds are one of the secondary metabolites that can be used as antibacterial. It can be concluded that the extract has strong antibacterial activity against E. tarda and potentially as antibacterial in aquaculture.

Aim: The present study was conducted to investigate the efficacy of different doses of Bangkal (Nauclea subdita) leaf extract on hematological and histological changes in kidney and liver of catfish (Pangasius hypophthalmus) infected by Aeromonas hydrophila. Materials and Methods: Catfish were experimentally infected with A. hydrophila at a dose of 108 cells/mL through intraperitoneal injection, and the hematological and histological changes in the kidney and liver of catfish against the pathogen were observed. Results: Not all concentrations of N. subdita caused a toxic effect in striped catfish. The clinical symptoms of catfish after infection with A. hydrophila and treatment with N. subdita leaf extract included morphological and behavioral changes. N. subdita leaf extract reduced mortality caused by A. hydrophila. Treatment with N. subdita leaf extract was effective in reducing the inflammation by decreasing the activity of neutrophils, monocytes, and lymphocytes. The Hb and Ht levels of catfish significantly decreased after exposure to 108 cells/mL of A. hydrophila and increased significantly after N. subdita treatment. Necrosis percentages in the kidney and liver also decrease after N. subdita treatment. Conclusion: The results indicate that N. subdita leaf extract stimulates the immunity and increases the resistance of catfish to A. hydrophila. N. subdita leaf extract may be used as a potential source for future drug development and food applications.