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Sediment geochemistry of the Jakarta region, a densely populated tropical coast, is studied — with particular focus on rivers discharging to Jakarta Bay. Weathering volcanics in the river catchment area control the composition of major elements, As, Cr and in part Cu. In contrast, Zn, Ni, Pb and partly Cu are affected by anthropogenic sources, mainly in central Jakarta City. The data reflect a high variability of local emission sources, among which metal processing industries, fertilizers or untreated animal waste may be important. In particular, the role of street dusts is emphasized. Locally, heavy metals reach levels considered to have adverse biological effects. River discharge leads to anthropogenic enrichment of heavy metals in the coastal sediments. Element data also show geogenic effects on the composition of the coastal sediments, such as mixing of detrital silicates with biogenic carbonates as well as suspended particulate matter from the ocean.

The Jakarta Bay Ecosystem is located in the vicinity of the megacity Jakarta, the capital city of Indonesia. Surrounding rivers and canals, carrying solid and fluid waste from households and several industrial areas, flow into the bay. Therefore, the levels of selected trace hazardous elements in water, surface sediments and animal tissues were determined. Samples were collected from two different seasons. The spatial distribution pattern of trace elements in sediment and water as well as the seasonal variation of the contamination were assessed. Quality assessment of sediment using the effects range median (ERM) showed that the concentrations of Hg, Cu and Cr at some stations exceeded the recommended values. Moreover, the concentrations of several trace hazardous elements in the sediments exceeded previously reported toxicity thresholds for benthic species.

The determination of pollution status is an important process of environmental quality monitoring especially in strategic waters for coastal areas, such as in Lampung Bay. An effective and sensitive Water Quality Index (WQI) method is needed, to accurately determine the environmental pollution status. This study aimed to compare the sensitivity of Storage and Retrieval of Water Quality data System (STORET) and Pollution Index (PI) as a WQI method, a case study from Lampung Bay coastal waters, Indonesia. Water quality analysis i.e. Dissolve Oxygen (DO), pH, salinity, nitrite, nitrate, phosphate and ammonia was conducted spatially (three zones of Lampung Bay; river mouth, aquaculture and bay area) and seasonally (April and October 2015). The study found that nitrate and phosphate values were exceeded the limits of water quality standard (Indonesia Ministry of Environment Decree No. 51/2004) for marine organisms. However it may still support the aquaculture activities. The two WQI methods produced different pollution status of Lampung bay. STORET was found to be more sensitive method. Pollution Index method revealed a status of moderately polluted while STORET showed heavily polluted status. Therefore, this study suggest the use of STORET index, compare to Pollution Index, in an assessment of pollution status at watershed area.

Previously designed endpoint PCR has been adapted for use with real time PCR to detect the presence of Salmonella typhimurium and Salmonella enteritidis in fish. Optimization of a standard curve in the presence of herring sperm DNA as background matrix indicated that the real time PCR highly efficient with the Pearson coefficient of determination (R2) value = 0.99937 and slope (M) value = -3.44. An enrichment method (overnight culture) significantly increased (p

Penelitian ini dilaksanakan untuk mengamati efektivitas karboksimetil kitosan (KMK) sebagai bahan pengkelat alami dan Na2 EDTA sebagai bahan pengkelat sintetis logam berat merkuri (Hg) pada ikan lele. Ikan lele yang digunakan adalah jenis lele dumbo yang diperoleh dari Bogor. Ikan dipelihara dalam kolam berukuran 380 x 150 x 60 cm 3. Air kolam sebanyak 570 L yang berisi 200 ekor ikan lele dipapar dengan Hg 60–90 ppb secara bertahap selama 1 bulan dan penggantian air kolam dilakukan setiap minggu. Sebelum pemaparan dengan Hg dilakukan, ikan lele dikondisikan pada kolam percobaan selama 1 minggu. Pada minggu ke dua ikan dipapar merkuri 60 ppb, kemudian konsentrasi merkuri dinaikkan 15 ppb setiap minggu sampai dengan minggu ke empat. Pemaparan dihentikan setelah minggu ke empat. Setelah itu ikan dipanen kemudian difilet dan dikelat dengan cara direndam dalam larutan KMK dan Na 2EDTA masing-masing pada konsentrasi 0; 0,5; 1,0; dan 1,5% selama 0, 30, 60, dan 90 menit. Perendaman dalam air digunakan sebagai kontrol terhadap perlakuan tersebut. Setiap perlakuan diulang sebanyak 3 kali. Pengamatan yang dilakukan meliputi kandungan awal dan kandungan akhir Hg setelah perlakuan perendaman. Analisis dilakukan menggunakan instrumen AAS (Perkin Elmer tipe Aanalyst800). Hasil pengamatan menunjukkan bahwa perendaman dalam KMK dan Na 2 EDTA 0,5% selama 30 menit memberikan hasil yang terbaik, dan tidak ada perbedaan antara KMK dan Na2EDTA dalam fungsinya sebagai absorben logam berat.

Penelitian aplikasi ekstrak daun jambu biji (Psidium guajava) untuk menghambat kemunduran mutu pindang tongkol (Scomber australasicus CV) telah dilakukan. Pada penelitian ini digunakan 4 konsentrasi ekstrak daun jambu (0, 3, 6, dan 9%) sebagai larutan perebus pada pengolahan pindang tongkol. Perubahan mutu ikan pindang diamati setiap 24 jam secara organoleptik, kimia (TVB, TBA) dan mikrobiologi (TPC, kapang), sedangkan pengamatan terhadap perubahan asam lemak dilakukan pada ikan pindang dengan perlakuan terbaik. Hasil penelitian menunjukkan bahwa penggunaan ekstrak daun jambu sebagai larutan perebus pada pemindangan ikan tongkol mampu menghambat peningkatan kadar TBA dan menekan oksidasi asam lemak tidak jenuh, tetapi tidak mampu menghambat peningkatan kadar TVB dan pertumbuhan mikroorganisme selama penyimpanan pada suhu ruang. Meskipun penggunaan ekstrak daun jambu menyebabkan warna pindang cenderung menjadi lebih gelap (kecoklatan), pindang tongkol yang direbus dengan ekstrak daun jambu mempunyai intensitas bau dan rasa tengik yang sangat rendah dan tekstur yang lebih baik bila disbanding kontrol. Perlakuan ekstrak daun jambu yang paling efektif sebagai pengawet pindang tongkol dengan nilai sensori terbaik adalah perlakuan ekstrak daun jambu pada konsentrasi 9%.