Backgrounds: Bacteriocin has been used widely in industry as a biopreservative agent. The objective of the present study was to investigate the potency of Bacteriocin isolated from tiger prawn Penaeus monodon and freshwater shrimp Macrobrachium rosenbergii as an anti-bacterial on fish. Methods: A total of ten candidates of probiotic bacteria consisted of five isolates from tiger shrimps (H1, H2, H3, H4, H5) and five isolates from freshwater prawns (W1, W2, W3, W4, W5) were evaluated. Bacteriocin wasBacteriocin was produced by centrifugation at a speed of 150 rpm and at 37 °C for 24 hours. The bacteriocin extract was purified by adding sulphate ammonium salt {(NH4) 2SO4} at 80% of the saturation level. Bacteriocin activity was determined using a diffusion method against pathogenic bacteria Vibrio alginolyticus, Aeromonas hydrophillaAeromonas hydrophilla and Pseudomonas stutzeri. Bacteriocins were analyzed usinganalyzedusing High Performance Liquid Chromatography (HPLC) and Fourier Transform Infra-Red (FTIR). The data were subjected to analysis of variance (ANOVA) and followed with Duncans multiple range test. Results: Bacteriocins produced by bacteria isolate H4 from tiger prawn indicated the highest bacteriocin activity againstbacteriocin activity against Pseudomonas stutzeri at stutzeri at the diameter of inhibition zone of 887.10 ± 409.24 mm 2/mL. While isolate W2 from freshwater shrimp indicated inhibition zone of 1466.96 ± 127.62 mm 2/mL. Both bacteriocins were purified by chromatography column using Sephadex LH-20. Conclusion s: This finding showed that bacterial isolates H4 and W2 have the potential to produce bacteriocins which inhibit the pathogenic bacteria. FTIR analysis showed an amide group at wave number 1652cm -1 contained in the bacteriocins of isolates H4 and W2.

Litter from the weathering of dead mangrove stems and leaves contains a lot of starch which has potential to be degraded by amylolytic bacteria into simple compounds with the help of the amylase enzyme. Amylolytic bacteria are bacteria that hydrolyze starch into simpler compounds namely glucose with the help of the amylase enzyme. This study aims to 1) isolate, identify and test sensitivity of amylolytic bacterial isolates found at the Purnama Dumai Marine Station, 2) the ability of amylolytic bacterial isolates to inhibit the growth of pathogenic bacteria (Escherichia coli, Pseudomonas aeruginosa and Vibrio alginolyticus) and 3) to determine the of amylolytic bacterial species by 16S rRNA sequence analysis. The results showed 10 bacterial isolates (TR 2, TR 6, TR 7, TR 9, TR 11, TR 13, TR 15, TR 16, TR 18 and TR 20) were able to inhibit the growth of pathogenic bacteria (E.coli, P.aeruginosa and V.alginolyticus). The sensitivity test of isolate TR 20 against E.coli was categorized into weak with inhibition zone diameter of 4.65 mm. Sensitivity of isolate TR 6 against P.aeruginosa was categorized into medium with inhibition zone diameter of 5.22 mm. Then sensitivity of isolate TR 11 against V.algynolyticus was categorized into medium with inhibition zone diameter of 5.55 mm. DNA analysis using 16S rRNA method and BLAST analysis showed similarity of each isolate. Isolate TR 6 was similar to Bacillus paramycoides strain MCCC 1A04098, isolate TR 11 was in a group of Enterobacter cloacae strain ATCC 13047 and TR 20 was in a group of Vibrio harveyi strains of NBRC 15634.

This research was conducted from April to July 2019 at the Center for Environmental Technology Laboratory (PTL), Geostech 820 Building, Serpong Region Puspitek, South Tangerang. The aim of this research was to determin growth of Chlorella vulgaris on media added with Pb at different concentrations, and to determine the ability to absorb Pb. The experimental method was conducted by using concentrations of Pb at 3 different levels consisting of 1 ppm, 5 ppm, 10 ppm in triplicate and control treatment without the addition of Pb. Each sample was analyzed by ICP-OES (Inductivly Coupled Plasma – Optical Emission Spectrometer). Data was analyzed by using ANOVA followed by LSD test. The growth of C. vulgaris biomass during the cultivation were Pb 1 ppm (10.38 g / l), k (9.10 g / l), Pb 5 ppm (8.36 g/l) and Pb 10 ppm (7.13) g/l). ANOVA test showed that different concentrations of Pb gave a very significant difference (Sig. <0.05) on the growth of C. vulgaris. Reduction in the concentration of Pb metal in culture media were Pb 10 ppm (96.8%), Pb 5 ppm (96.2%), Pb 1 ppm (90%) and there is no Pb found in control. ANOVA test results showed that C. vulgaris had a very significant effect (Sig. <0.05) on the decrease of Pb metal concentration. This shows that C. vulgaris has the capacity as bioremediation of Pb with different concentrations.

This study aims to find out that Bacillus paramycoides and Enterobacter cloacae bacteria can produce amylase enzymes and have the ability to degrade organic matter, especially mangrove litter. From this study it was found that the optimal growth of B.paramycoides and E. cloacae bacteria occurred at 12th hour. The results of measurements and calculations of absorbance values ​​at 630 10.238 x 108 cells/mL (B. paramycoides) and 12.030 x 108 cells/mL (E. cloacae) using the spectrophotometric method. Meanwhile, with the TPC method at 12 hours, the number of bacterial cells was 2.08 x 108 CFU's/ml (B. paramycoides) and 2.44 x 108 CFU's/ml (E. cloacae). The ability to produce the largest amylolytic bacterial amylase enzyme also occurred at 12 hours as much as 0.306 mg/mL (B.paramycoides) with an increase of 0.046 mg/mL and 0.243 mg/mL (E. cloacae) with an increase of 0.028 mg/mL. The bacteria that have the highest amylase enzyme ability is E.cloacae as evidenced by the diameter of the clear zone of 10.10 mm. Testing the ability of amylolytic bacteria in degrading mangrove litter was carried out by adding amylase enzyme as much as 0%, 50% and 100%. Amylolytic bacteria can degrade organic matter by hydrolyzing starch contained in mangrove litter. The most degraded starch content was in the 100% enzyme treatment, which was 1.021 mg/mL (B. paramycoides) and 1.189 mg/mL (E.cloacae).

Lactic acid bacteria (LAB) have been isolated successfully from the tiger grouper Epinephelus fuscoguttatus intestine. However, their genus or species have not been identified. Therefore, the objective of the present study was to characterize the three isolated LAB (KSBU-12C, KSBU-5Da, and KSBU-9) based on their phenotype and genotype. The LAB phenotype was examined by observing morphological features including cell morphology, spore production and motility. The physiological tests were performed in 6.5% NaCl at the  temperatures of 10 oC and 45 oC, and the biochemical tests were evaluated based on the production of enzymes catalase, oxidase and arginine dehydrolase, following  the Standard Analytical Profile Index, API 50 CH kit.  The genotype was examined based on 16S rDNA gene sequence analysis , and the products were analyzed using the BLAST (Basic Local Alignment Search Tool) NCBI database. The three isolates (KSBU-5Da, KSBU-12C, and KSBU-9) were categorized into the genus Enterococcus. 16S rDNA sequence analysis indicated that the isolates had 99% similarity to E. hirae ATCC 9790, registered in GenBank with accession number NR_075022.1. It was concluded that the three LAB isolates taken from the tiger grouper Epinephelus fuscoguttatus are E. hirae.