Development of Oil Bioremediation Research on Marine Environment in Indonesia

Indonesian marine environment is one of the most vulnerable waters from oil pollution in the world. Therefore, a hard effort to minimize oil pollution impact is really needed. Physical and chemical approaches have been already popular to combat oil pollution; one of the other promising techniques is bioremediation, the use of microorganism to detoxify or remove pollutants. Research and application of bioremediation on soil environment has been started in Indonesia; however, in marine environment it is still need to be studied due to more complicated aspects and also difficulties. Development of bioremediation study on marine environment in Indonesia has been started from enumeration, isolation and identification of oil degrading (hydrocarbonoclastic) bacteria. Researches on taxonomic and functional genes have been conducted. Biostimulation and bioaugmentation studies are ongoing research which conducted from laboratory scale and microcosm scale to field experiment (sand column). To have a manual or guidelines on conducting bioremediation in marine environment is not easy and still many steps have to be done. Several aspects concerning with this study such as the diversity of polluted sites characteristic, oils characteristic, oceanographic conditions and engineering has to be studied comprehensively

OPTIMIZATION BACTERIAL DENSITY AND FERTILIZER DOSAGE FOR BIOREMEDIATION OF OIL CONTAMINATED SANDY BEACH: A CASE OF CILACAP, INDONESIA

Bioremediation, involving biostimulation and/or bioaugmentation, is a promising method to overcome oil spills in Cilacap coastal waters. Cilacap coastal area has high risk on oil pollution. This study investigated the stimulatory effect of nitrogen concentration, bacterial density and the composition of bacterial culture in enhancing oil degradation in this area. The applications of 4 different concentrations of Slow Release Fertilizer (SRF) and 2 different densities of bacterial cells in the form of single (RCO/B/08_008) and mixed culture were employed in microcosm experiments for 28 days. The efficacy of combining bacterial culture and fertilizer application in various concentrations was also tested. Oil degradation, bacterial growth and environmental parameters were monitored periodically during the experiments. The results showed that oil degradation rate was more influenced by nutrient concentration (biostimulation) than bacterial number or culture composition (bioaugmentation) added. The efficacy of biostimulation in degrading oil was better than that of bioaugmentation. Biostimulation increased oil degradation up to 6.4 times higher than the control. The optimum of fertilizer concentration added was 7.5 mg N/g (C:N ratio of 1,000:75), which increased depletion rate both in biostimulation-only and the combination of biostimulation with bioaugmentation up to 6.4 and 7.5 times higher than the control, respectively. It is suggested that bioremediation of oil-contaminated sandy beach in Cilacap would be optimal by employing a combination of Slow Release Fertilizer at concentration having C/N ratio = 1,000 : 75 and RCO/B/08_008 culture at density of 0.5 x 108 cells/mL (100% homology with Alcanivorax sp. TE-9)

Optimization Bacterial Density and Fertilizer Dosage for Bioremediation of Oil Contaminated Sandy Beach: a Case of Cilacap, Indonesia

Bioremediation, involving biostimulation and/or bioaugmentation, is a promising method to overcome oil spills in Cilacap coastal waters. Cilacap coastal area has high risk on oil pollution. This study investigated the stimulatory effect of nitrogen concentration, bacterial density and the composition of bacterial culture in enhancing oil degradation in this area. The applications of 4 different concentrations of Slow Release Fertilizer (SRF) and 2 different densities of bacterial cells in the form of single (RCO/B/08_008) and mixed culture were employed in microcosm experiments for 28 days. The efficacy of combining bacterial culture and fertilizer application in various concentrations was also tested. Oil degradation, bacterial growth and environmental parameters were monitored periodically during the experiments. The results showed that oil degradation rate was more influenced by nutrient concentration (biostimulation) than bacterial number or culture composition (bioaugmentation) added. The efficacy of biostimulation in degrading oil was better than that of bioaugmentation. Biostimulation increased oil degradation up to 6.4 times higher than the control. The optimum of fertilizer concentration added was 7.5 mg N/g (C:N ratio of 1,000:75), which increased depletion rate both in biostimulation-only and the combination of biostimulation with bioaugmentation up to 6.4 and 7.5 times higher than the control, respectively. It is suggested that bioremediation of oil-contaminated sandy beach in Cilacap would be optimal by employing a combination of Slow Release Fertilizer at concentration having C/N ratio = 1,000 : 75 and RCO/B/08_008 culture at density of 0.5 x 108 cells/mL (100% homology with Alcanivorax sp. TE-9)

Optimization bacterial density and fertilizer dosage for bioremediation of oil contaminated sandy beach: a case of cilacap, indonesia

Bioremediation, involving biostimulation and/or bioaugmentation, is a promising method to overcome oil spills in Cilacap coastal waters. Cilacap coastal area has high risk on oil pollution. This study investigated the stimulatory effect of nitrogen concentration, bacterial density and the composition of bacterial culture in enhancing oil degradation in this area. The applications of 4 different concentrations of Slow Release Fertilizer (SRF) and 2 different densities of bacterial cells in the form of single (RCO/B/08_008) and mixed culture were employed in microcosm experiments for 28 days. The efficacy of combining bacterial culture and fertilizer application in various concentrations was also tested. Oil degradation, bacterial growth and environmental parameters were monitored periodically during the experiments. The results showed that oil degradation rate was more influenced by nutrient concentration (biostimulation) than bacterial number or culture composition (bioaugmentation) added. The efficacy of biostimulation in degrading oil was better than that of bioaugmentation. Biostimulation increased oil degradation up to 6.4 times higher than the control. The optimum of fertilizer concentration added was 7.5 mg N/g (C:N ratio of 1,000:75), which increased depletion rate both in biostimulation-only and the combination of biostimulation with bioaugmentation up to 6.4 and 7.5 times higher than the control, respectively. It is suggested that bioremediation of oil-contaminated sandy beach in Cilacap would be optimal by employing a combination of Slow Release Fertilizer at concentration having C/N ratio = 1,000 : 75 and RCO/B/08_008 culture at density of 0.5 x 108 cells/mL (100% homology with Alcanivorax sp. TE-9)

The Efficacy of Bioaugmentation on Remediating Oil Contaminated Sandy Beach Using Mesocosm Approach (Efikasi Tehnik Bioaugmentasi dalam Memulihkan Pantai Berpasir Tercemar Minyak Menggunakan Pendekatan Mesokosm)

Bioremediation is basically consists of two approaches, biostimulation and bioaugmentation. The efficacy of bioaugmentation for combating oil pollution in field application is still argued. The purpose of study was to evaluate the efficacy of bioaugmentation and to compare the affectivity of single strain and consortium application in remediating oil polluted sandy beach. Experimental study in a field has been conducted with two (2) treatments and one (1) control in three different plots. The treatmens were introduction of a single strain (Alcanivorax sp TE-9) and a consortium (Alcanivorax sp. TE-9, Pseudomonas balearica st 101 and RCO/B/08-015) cultures into oil contaminated sediment. The experiment in mesocosm approach was taken place in Cilacap coast. Arabian light crude oil was used in the concentration of 100.000 mg.kg-1 sediment. Changes of oil concentration, bacterial density and pore water quality have been monitored periodically for 3 months. The result showed that oil degradation percentage and bacterial growth in both treatments were higher than in control. After 3 months, the percentage of oil degradation experiment in control, single strain and formulated consortium treatments were observed at 60.4%, 74.5% and 73.5%. It proves that bioaugmentation tehnique can enhance significantly oil biodegradation in sandy beach. The applications of bacteria in single or consortium culture give no different impact on their affectivity for bioremediation in Cilacap sandy beach. By data extrapolation it can be predicted that both of treatments able to reduce remediation time from 210 days into 135–137 days. Bioaugmentation can be proposed as a good solution for finalizing oil removing in Cilacap sandy beach when oil spilled occurred in this environment. Keywords: Bioremediation, bioaugmentation, oil, sandy beach, Alcanivorax, mesocosm, Cilacap   Bioremediasi pada dasarnya terdiri dari dua pendekatan yaitu biostimulasi dan bioaugmentasi. Teknik bioaugmentasi  dalam menanggulangi pencemaran minyak di lapangan masih diperdebatkan efektivitasnya. Penelitian ini bertujuan untuk mengevaluasi efikasi tehnik bioaugmentasi serta membandingkan efektivitas kultur tunggal dan konsorsium  dalam memulihkan pantai berpasir tercemar minyak. Studi eksperimental di lapangan telah dilakukan dengan menggunakan dua perlakuan dan satu kontrol di tiga plot berbeda, Perlakuannya adalah penambahan bakteri kultur tunggal (Alcanivorax sp TE-9) dan bakteri konsorsium (Alcanivorax sp. TE-9, Pseudomonas balearica st 101 dan RCO/B/08-015) ke dalam sedimen yang tercemar minyak. Eksperimen dengan pendekatan mesokosm dilakukan di pantai Cilacap. Minyak mentah ringan Arabia dengan konsentrasi 100.000 mg.kg-1 sedimen digunakan sebagai bahan cemaran. Perubahan konsentrasi minyak, kepadatan bakteri dan parameter lingkungan diamati secara periodik selama 3 bulan percobaan. Hasil penelitian menunjukkan bahwa persentase degradasi minyak dan densitas bakteri di sedimen perlakuan lebih tinggi daripada kontrolnya. Setelah 3 bulan eksperimen, persentase degradasi minyak pada kontrol, perlakuan kultur tunggal dan konsorsium masing-masing teramati 60.4%, 74.5% and 73.5%. Hal ini membuktikan bahwa tehnik bioaugmentasi secara signifikan mampu meningkatkan biodegradasi minyak di pantai berpasir. Pemberian mikroba dalam bentuk kultur tunggal ataupun konsorsium mempunyai efektivitas yang tidak berbeda untuk proses bioremediasi di pantai berpasir Cilacap.  Dengan ekstrapolasi data dapat diduga bahwa kedua perlakuan bioaugmentasi ini mampu mempercepat waktu pemulihan lingkungan dari 210 hari ke 135-137 hari. Bioaugmentasi dapat diusulkan sebagai solusi yang cukup baik untuk menghilangkan minyak pada tahap akhir pembersihan pantai berpasir Cilacap, jika terjadi tumpahan minyak di lingkungan ini. Kata kunci: single strain, consortium, bioaugmentation, oil, bioremediation, sandy beach,  Alcanivorax, Cilaca

Microbial Biofilm of Plastic in Tropical Marine Environment and their Potential for Bioremediation of Plastic Waste

Plastic debris has become a global problem due to its widespread distribution and accumulation in the marine environment. Indigenous bacteria in the marine environment are able to quickly contaminate plastic surface and assemble to form successional plastisphere-specific bacterial. The formation of microbial biofilms on the plastic surface can indirectly initiate the degradation of plastic polymers. The environmental conditions of the tropical region make the growth of microbial biofilms become faster. However, the study on the biodiversity of microorganisms in marine plastic debris is limited to the northern hemisphere, which includes subtropical and temperate regions. This review provides current studies of biodiversity and community structure of plastisphere in tropical environments, including bacteria and microalgae, and their potential to degrade the plastic polymer. A systematic literature search has been conducted using Scopus with different combinations of keywords. In addition, Google Scholar databases were also used to find more studies on some specific topics, including plastic degrading organisms. The climate-associated areas have been grouped according to the latitude of the study site into tropical, subtropical, and temperate latitudes. The microorganisms analyzed in this review are only bacteria, actinobacteria, and microalgae

HYDROCARBONOCLASTIC BACTERIA FROM JAKARTA BAY AND SERIBU ISLANDS

Jakarta Bay has been known as one of the most polluted marine environment in Indonesia, with no exception by oil. Seribu Islands waters, located in the north of Jakarta Bay may have been impacted by this polluted condition.It’s sometimes also hit by oil spillage from pipe leakage. The purpose of this study is to isolate and identify hydrocarbonoclastic bacteria (oil and Polyaromatic Hydrocarbon degrading bacteria) from Jakarta Bay and Seribu Island waters. The bacteria were isolated from water and sediment/sand. Isolation was prepared by enriched samples in SWP medium with Arabian Light Crude Oil (ALCO). Screening for PAH degrading bacteria has been completed by using sublimation plate method in ONR7a medium and screening for oil degrading bacteria were conducted by using oil plated method with the same medium. Bacteria identifications were done based on l6sRNA gene. The results were analyzed using BLAST and showed that 131 potential hydrocarbonoclastic bacteria have been isolated from Jakarta Bay and Seribu Island waters. Most of them were oil degrading bacteria (41.98%) and the rest were PAH degrading bacteria. Oil pollution level may impact the number of strain of hydrocarbonoclastic bacteria isolated. Among the hydrocarbonoclastic bacteria isolated from Jakarta Bay and Seribu Islands, Alcanivorax, Marinobacter, Achromobacter and Bacillus were common hydrocarbonoclastic genera in Jakarta Bay and its surrounding waters. Alcanivorax spp. is important oil and PAH-degrader found not only in temperate waters, but in tropical waters as well

ORGANIC MATTER AND NUTRIENT PROFILE OF THE TWO-CURRENT-REGULATED-ZONE IN THE SOUTHWESTERN SUMATRAN WATERS (SSW)

The Indian Ocean is influenced by monsoon systems which alter the ocean’s physical and chemical properties. Specifically, the southwestern Sumatran waters in the eastern Indian Ocean are considered a dual current regulated zone i.e. affected by South Equatorial Counter Current (SECC) and South Java Current (SJC). This area is considered as having an important role in the transfer of organic matter or the biological pump. However, the information about this area is minimal, especially in terms of organic matter and nutrient profile. This study will update the recent information about the area, including the profile of particulate organic matter (POM), macro-nutrients, total suspended solids (TSS), macromolecule-degradingbacteria, and soft bottom macrobenthic organisms sampled from 26 stations in both the SECC-regulated zone and the SJC-regulated zone. The physical profile is typical of tropical watersand both zones have a distinct profile of organic matter and nutrients. The particulate organic carbon (POC), particulate organic nitrogen (PON), and TSS of the SECC-regulated zone can be considered higher than those of the SJC-regulated zone. This region is categorized as mesotrophic waters, especially from the surface up to 100 m. The production of nutrients and organic matter in the water column in this area contribute significantly to the abundance of heterotrophic bacteria and benthic organisms