Penggunaan Marka DNA dalam Seleksi Induk Ikan Kerapu Macan (Epinephelus fuscoguttatus) yang Tahan Terhadap Bakteri Vibrio alginolyticus

The objective of the present study was to use selected RAPD markers (Primer UBC-122 and YNZ-22) in parental selection to the bacterial Vibrio alginolyticus resistance in Tiger groupers (Epinephelus fuscoguttatus).  Eighteen fish parent samples were challenged with Vibrio alginolyticus and parental selection was examined by a PCR-RAPD method.   The results showed that from 18 fish samples, primer YNZ-22 generated 18 fragments while primer UBC-122 generated 8 fragments only (KHP, KB, HB, PB, MKH, MH, K and MK).  In addition, the average number of fragments from each samples generated from primer-YNZ was higher (3,2) than from UBC-122 (2,3). This indicates that primer YNZ-22 is better than primer UBC-122 to use in parental selection to the Vibrio alginolyticus resistance in Tiger groupers.  From the parental selection, five fish parents (KHP, PB, MH, K and  MK) were selected for their high resistance to the bacterial Vibrio alginolyticus

Effects of Salinity and Bioflocculation during Euglena sp. Harvest on the Production of Lipid, Chlorophyll, and Carotenoid with Skeletonema sp. as a Bioflocculant

Euglena sp. is a freshwater microalga that produces useful metabolites in its biomass. The cultivation with oxidative stress treatments, such as salinity, plays a major role in maintaining the optimal cellular metabolic rate for the optimized growth of Euglena sp. for the production of lipids for biodiesel as well as carotenoids and chlorophyll, which are cell defense pigments that are beneficial for health. A bioflocculation method that uses microalgal flocculants, such as Skeletonema sp., is an alternative harvesting technique that is cost and energy saving. The effect of salinity and bioflocculation treatment on freshwater microalgae has not been widely studied. Therefore, this research determined the effect mechanism of salinity and bioflocculation in the production of lipids, chlorophyll, and carotenoids in Euglena sp. with Skeletonema sp. as a bioflocculant. In this research, the cultivation of Euglena sp. was carried out in Cramer–Myers medium for seven days under salinity treatments of 5, 10, 20, and 0 g/L, and the cultivation of Skeletonema sp. was performed for eight days in F/2 medium with modified silicate removal. Bioflocculation was performed by mixing Euglena sp. and Skeletonema sp. at ratios of 1:1, 1:0.5, and 1:0.25. The research results showed that salinity treatment, in general, succeeded in increasing the growth and production of lipid, chlorophyll, and carotenoid metabolites. The addition of Skeletonema sp. to the culture of Euglena sp. increased the precipitation percentage. A high mixing ratio increased the lipid level but decreased those of chlorophyll and carotenoid metabolites

THE EFFECT OF VITAMIN C AND AEROMONAS VACCINE ON THE IMMUNE RESPONSE AND DISEASE RESISTANCE OF GROUPER (Epinephelus fuscoguttatus)

We evaluated the effectiveness of vitamin C and Aeromonas salmonicida vaccine in grouper (Epinephelus fuscoguttatus) for increasing immune responses and protection against A .salmonicida. The vitamin C used was polyethoxylated ascorbic and tocopherol. The vaccine was prepared from formalin-killed cells and concentrated extracellular products of a single isolate A. salmonicida. Bath immersion vitamin C and vaccine trials were conducted for 60 min. Fish used had a mean weight 25 g. Control groupers were injected with tryptic soy broth. The results showed that vitamin C enhanced phagocytic activity in head kidney leucocytes of grouper 7, 14, 28 and 36 days after treatments. A significant different of the antibody titre was found between control fish and the treated fish at 42 days after treatments. In addition, at day 42, Relative Percent Survival (RPS) for control group was 53.3 %, vitamin C-treated group was 80.0 % and vaccinated group was 90.0 %. The results of this study suggest that bath immersion of vitamin C provided an increasing of phagocytic activity (non-specific immune responses), titre antibody (specific immune responses) and protection against A. salmonicida infection in grouper. A. salmonicida vaccine also en-hanced titre antibody and protection against A. salmonicida infection in grouper

Effect of chlorophyll in alginate-based edible film in inhibiting spoilage of fish snacks

Edible films are environmentally biodegradable materials used for food packaging. The edible green alga Caulerpa racemosa has antimicrobial properties; however, its chlorophyll-based bioactive compounds can be damaged when heated so it is prepared in microcapsules. Our research evaluated the effect of Caulerpa microcapsules on an alginate-based edible film on film properties and food spoilage. The microcapsules were used at concentrations of 0%, 0.5%, 1%, and 1.5%. The edible film was measured for film properties, total phenolic content (TPC), antioxidant activity (DPPH), functional group (FTIR) and microstructure (SEM). Food spoilage was evaluated on a popular fish-based product (fish bubble snacks). Bacterial strains of Escherichia coli and Staphylococcus aureus were used to evaluate antimicrobial effectiveness of the edible films. The addition of Caulerpa microcapsules had no significant negative effect on physical properties of the alginate-based film, while the smoother and more homogenous surface should enhance the barrier properties of the film. The slow and evenly distributed release of active compounds from the microcapsules increased resistance to Rhizopus sp. and significantly reduced the proliferation of E. coli but not S. aureus on coated fish snacks. Caulerpa racemosa can be used to enhance the effectiveness of alginate-based films in delaying spoilage and could extend product shelf-life

DNA Barcoding of Freshwater and Diadromous Taxa in Wallacea

Barcodes for Maros karst and Luwuk Banggai in 202