Cyanobacteria have been known as a potential extracellular-polysaccharide (EPS) producer. The objective of this study was to screen the marine cyanobacteria as potential antidiabetic agents. The present investigation was designed to determine the antidiabetic activity of EPS, intracellular-polysaccharide (IPS) and biomass extracts from marine cyanobacteria isolates. 10 cyanobacteria isolates were cultivated in IMK medium, at 25 o C for 21 days. The morphology of cells was identified by a light microscope. EPS and IPS were separated by ethanol precipitation method and their antidiabetic activity was analyzed by the inhibition of α-glucosidase activity method. Results of morphology identification of 10 cyanobacteria isolates consist of Oscillatoria limnetica, Oscillatoria sp., Leptolyngbya sp., Pseudanabaena sp., Lyngbya sp. and Phormidium sp., Coelastrella sp., Aphanothece sp. and Synechococcus sp., and Chroococcus sp. Almost all of EPS from marine cyanobacteria isolates were potential as inhibitor of α-glucosidase, except for Oscillatoria limnetica and Phormidium sp. isolates. The highest activity in α-glucosidase inhibition was detected in Pseudanabaena sp. (14.02%) and Chroococcus sp. (13.0%) isolates.

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Plastic wastes and petrochemical-based polymer materials have become a serious problem to the environment due to the characteristics of these materials that are difficult to degrade in nature. Polyhydroxyalkanoates (PHA) is one type of biodegradable plastics that have a great potential to replace the widely-used hydrocarbon plastics since it will decompose completely into carbon dioxide and water after burial for several months in the soil. PHA can be produced by microorganisms such as bacteria and algae through a fermentation process. The objective of this research is to obtain bacteria that can produce PHA. Screening was carried out by two sequential steps, qualitative and followed by quantitative methods. An amount of 29 bacteria strains isolated from Indonesians soil were screened for this purpose. The qualitative screening was conducted by growing the bacteria in a specific medium containing Nile red dye. The results showed that 19 strains were positive, generated pink to orange colonies under UV light at 235 nm. It was also confirmed by fluorescence microscope. The quantitative screening was performed by measuring the intracellular materials (predicted as PHA) of the bacterial cells by gravimetric method. The results indicated that the highest average of PHA content was 52.9%, 35.6% and 35.4 of dried cell weight, respectively for the Burkholderia sp B73, Bacillus sp B58, Bacillus toyonensis B50 and Staphylococcus cohni B66.

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Priatni S, Ratnaningrum D, Kosasih W, Sriendah E, Srikandace Y, Rosmalina T, Pudjiraharti S. 2018. Protein and fatty acidprofile of marine fishes from Java Sea, Indonesia. Biodiversitas 19: 1737-1742. Indonesia is the second largest producer of capturefisheries products in the world and the most capture fisheries production comes from marine fisheries. Marine fish is a source of protein,amino acid, saturated and unsaturated fatty acids, which are important components of diet. The objective of the study was to investigatethe protein and fatty acids profile of nine marine fish samples from Java Sea of Indramayu West Java, Indonesia. The analysis datashowed that the total protein content of fish samples ranged from 61.07% (Pampus argenteus) to 86.56% (Tetraodontidae). Meanwhile,total lipid content of fish samples ranged from 1.73% (Tetraodontidae) to 9.82% (Leiognathus equulus). The concentration of α-AminoNitrogen (AN) of fish protein hydrolysate was ranging from 31 mM (Nemipterus hexodon) to 69 mM (Mystacoleucus padangensis)and% Degree of Hydrolysis (DH) was ranging from 9.33% to 20.39%. The molecular weight of protein fish samples had similar profilesprimarily for almost all samples, which could be observed from a typical band with the weight around 49 kDa. The saturated fatty acid(Ʃ SFA) compositions of fish species ranged from 1094.03-4233.03 μg/g. Oleic acid (MUFA) content of all fish species ranged from257.91-1216.06 μg/g. However, only three fish species contain of Poly Unsaturated Fatty Acid (PUFA) linoleic acid as the following;Selaroides leptolepis (171.36 μg/g), Oxyeleotris marmorata (249.40μg/g) and Tetraodontidae (140.35 μg/g). The highest SFA contentwas found in S. leptolepis with palmitic acid (C16:0) as the dominant saturated fatty acid (2320.88 μg/g). S. leptolepis also containedhigh oleic acid (1216.06 μg/g) and linoleic acid (171.36 μg/g).