Nitrile and amide bioconversion have received increasing attention due to their ability to provide a range of commercially important chemicals. The experiment was conducted to investigate the potential of bacterial isolate GLB5 to convert methyl cyanide and phenyl cyanide. The samples were collected from various industrial waste. Selection of isolates to utilize Â these substrates as a sole source of energy, carbon and nitrogen was conducted on 96 whell microtitter plates, based on the growth ability using INT (Iodo nitrotetrazolium chloride) reagent. Based on the growth Â pattern, it showed that the bacterial isolate GLB5 grew well and it was capable of utilizing Â methyl and phenyl cyanide compound as the sole source of carbon and nitrogen. Â The isolate GLB5 was isolated from industrial waste of Batik factory in Cirebon, and Â identified as Rhodococcus pyridinovorans. Bioconversion of methyl cyanide using whole cells of R. pyridinovorans GLB5 showed that ethanamide (C2H5NO) and ethanoic acid (C2H4O2) were detected. Formation of ethanamide and ethanoic acid as the product of bioconversion, indicated that the nitrile hydratase and amidase enzymes Â involved in the bioconversion process. Phenyl carboxamide (C7H7NO) as the product of phenyl cyanide bioconversion was also detected, Â although Â in Â low Â concentration. In this study, R. pyridinovorans GLB5 was capable of completely converting 300 mM methyl cyanide to Â± Â 140 mM ethanoic acid in relatively short times (<60 minutes).
Dibenzothiophen (DBT) adalah salah satu senyawa Hidrokarbon Aromatik Polisiklik yangÃ‚Â dikenal beracun di lingkungan. Sebagian besar PAH bersifat karsinogenik dan persistenÃ‚Â di lingkungan. Teknik Biostimulation digunakan untuk mengisolasi bakteri indigen dariÃ‚Â Muara Baru yang mampu mendegradasi DBT. Tujuan utama dari penelitian ini untukÃ‚Â mengisolasi dan meneliti bakteri laut yang dipilih untuk mendegradasi senyawa DBT.Ã‚Â Hasil penelitian menunjukkan bahwa bakteri isolat M4 (Sphingomonas paucimobilis)Ã‚Â dapat tumbuh optimal pada 30 oC dengan 1,6 X 109 sel / ml dan waktu penggandaanÃ‚Â (td) adalah 6 jam. Pertumbuhan Sphingomonas paucimobilis pada konsentrasi 2%Ã‚Â NaCl adalah 2,6 X 109 dengan Waktu penggandaan 11 jam. Proses biodegradasi DBTÃ‚Â menunjukkan bahwa Km dan Vmaks untuk KNO3 adalah 0,0307 jam-1 dan 12,27 mglt-1 h-1. KNOÃ‚Â 3 dan NH4NO3 adalah sumber yang cocok dari nitrogen untuk mempercepatÃ‚Â kecepatan biodegradasi Sphingomonas paucimobilis. Efisiensi degradasi mereka adalahÃ‚Â 62,5% dan 57,6%.
Indonesia sebagai negara tropis memiliki biodiversitas yang sangat tinggi. Keanekaragaman hayati ini diperkirakan mencerminkan keanekaragaman kimiawi sekaligus keragaman genetik yang dapat dimanfaatkan untuk mencari biokatalis baru. Enam isolat bakteri yaitu GLB5, LP3, TPIK, MICC, 23A2, dan 23A2 telah diisolasi dari berbagai limbah industri dan mempunyai potensi sebagai pendegradasi nitril.ÃÂ Pengucilan, identifikasi dan purifikasi gen penyandi enzim nitrilase dari keenam isolat bakteri tersebutÃÂ telah dilakukan. Dari kegiatan penelitian ini 3 isolat bakteri unggulan, yaitu GLB5, LP3, dan TPIK teridentifikasi sebagai Rhodococcus pyridinivorans, sedangkanÃÂ MICC teridentifikasi sebagai Bacillus substilis, 23A2 teridentifikasi sebagai Brevibacillus brevis, dan 26A2 teridentifikasi sebagai Microbacterium oxydans. Peta untaian basa nukleutida dari gen penyandi enzim nitrilase dari ketiga isolat yaitu GLB5, LP3, dan TPIK telah terpetakan dengan ukuran gen nitrilase sebesar 960 bp. Hasil analisis dengan BLASTN memperlihatkan bahwa fragmen gen nitrilase yang diamplifikasi dengan primer Nit1101F dan Nit1101R mempunyai homologi yang tinggi terhadap Rhodococcus rhodochrous strain tg1-A6 nitrilase gen dengan persentase kesamaan sebesar 96% .ÃÂ Kata Kunci: Gen, isolasi, nitril, degradasi, enzimÃÂ
Picrate paper test kit for the semiÃ¢â¬âquantitative determination of cyanogenic potential was developed in thisexperiment. The method is relatively simple, easy to use and might be applicable in the field by unskilled person.Paper test was attached on tubes containing sample (100 mg) in aquadest (0,5 mL) and then was immediatelycovered tightly and incubated overnight at room temperature. The colour of picrate paper test changed graduallytowards reddish brown, and its colour was compared with standart colour chart which included 0-800 ppm cyanidethat was also developed in this study. The reddish brown colour of paper test was correlated with cyanideconcentration on the sample. In order to obtain a more accurate detection of cyanogenic compound the paper testwas eluted with 5 mL water or aquadest and the absorbance was measured at 510 nm.Keywords: cyanogenic potential, picrate paper test, semi-quantitative method, simple method, cassava (Manihotesculenta Cranz)
ABSTRACTIsolation of Bacteria Degrading Phenanthrene in Batanta- Salawati Districts Raja AmpatPapua. Polycyclic aromatic hydrocarbons (PAHs) are important environmental contaminantsin soil and water. These compounds have a potential risk to human health, as many of them arecarsinogenic and toxic to marine organisms such as diatome, gasthrophode, mussel, and fish.Phenanthrene is one of the hazardous hydrocarbon compounds. The purpose of this researchwas to characterize microbial strains from Batanta-Salawati Raja Ampat Papua Island and theirability to remove phenanthrene. Two isolates were identified at their physiological characteristicsbased on salinity tolerance, pH tolerance and the composition of nitrogen base. Molecularidentification based on 16S rRNA gene sequences indicated that bacteria had the highestsimilarity with Rhodobacteraceae bacterium F9 and Roseobacter sp. RW 37.Rhodobacteraceae bacterium F9 could grow optimum on ONR7a media with 5% salinity andat pH of 5-7,5 while Roseobacter sp. RW 37 could grow optimum on ONR7a media with 2%salinity and at pH of 6,2-7,5.Key words: Phenanthrene, physiological characteristic, molecular identification, Raja Ampat
ABSTRACTScreening of Nitrile and Protein-Degrading Marine Bacteria Isolated from Sponge in TernateSea Water. Thirty three marine bacteria have been isolated from marine sponge in Ternate byenrichment culture. Screening bacteria-degrading nitrile was done by microtitter plate methodbased on growth ability tested by Iodonitrotetazolium chloride. Product of nitrile degradationwas determined by Gas Chromatography (GC) and the potential bacteria-degrading proteinwas also screened by using selected media which contained casein. The results showed thattwenty one isolates were able to show the clearing zone in selected media. Five isolatescapable of utilizing acetamide as the sole source of carbon and nitrogen. Acetate and ammoniaproduced for hydrolysis acetonitrile by using resting cell of Lysobacter sp.Key words: Nitrile, bacterium, sponge, Ternate
Potential nitrile degrading microbes have been isolated from marine sponge, marine water and soil in Enggano Island. Nitrilase enzyme has a function in degrading nitrile compund. Nitrilases are important industrial enzymes because of their ability to produce biologically active to degrade enantiomers, such as S-(+)-1-(4â-isobutylphenyl) propionic acid (S-(+)-ibuprofen) and R-(-) mandelic acid. Mandelic acids, which are important as pharmaceutical intermediates, can be produced in enantiomerically pure form by the hydrolysis of their corresponding nitrile. The aim of the study was to explore the diversity of nitrile degrading bacteria in Enggano Island, and their ability to utilize nitrile as a substrate growth. Screening of such microbes were carried out by using microtitter plate method based on growth ability tested by INT (Iodonitrotetrazoliumchloride). Degradation product was determined by High Performance Liquid Chromatography (HPLC). Seventy nine bacteria were able to grow on acetamide, acetonitrile, benzonitrile, adiponitrile, mandelonitrile, succinonitrile, lactonitrile, dan benzilcyanide as the sole source of carbon and nitrogen. Two isolates, YIM 56238 and PO69, have shown to enantioselectively hydrolyze racemic mandelonitrile to mandelic acid. Based on 16S rRNA gene identification, these bacteria have the highest sequence similarity to Microccous endophyticus strain YIM 56238 and Rhodococcus pyridinivorans strain PO69.
Immobilized microalgae Chlorella pyrenoidosa was applied initially to nutrient and heavy metal removal of wastewater. Immobilized microalgae using alginate was then developed for aquaculture application, such as controlling fish water culture quality to uptake concentration of ammonium, nitrate and to increase the oxygen level in water. During immobilization, algal cell maintain their respiratory and photosynthetic activities as that cell in the normal condition. The objective of this research was to examine the role of C. pyrenoidosa immobile on controlling the water quality by measuring ammonium, nitrate, and dissolved oxygen content. Five aquariums consisted of 40 litres of water were filled with 20 Nile Tilapia (Oreothromis niloticus) with the average weight between 1.6 and 1.7 g. The immobile algae cell were packaged in two nillon porus bag (pore size was 2x3 mm in diameter) and each immobile cell had 4 millimeter in diameter. Each aquarium was added with 3000, 4000, 5000, and 6000 of immobile cell. The treatment had 2 replicates. The results showed that the aquarium filled with 4000 beads of immobile cell gave the best result. The ammonium content on the water decrease 6,626 ppm/day, nitrate content on the water decreased 13.99 ppm/ day, soluble oxygen raised 0.766 per day and fish biomass raised 1.56 g/fish for 15 days.
Biosurfactants are the surface-active molecules synthesized by microorganisms. The microbial surfactant were interesting because of the biodegradable and have many application in industry. With the advantage of environmental compatibility, the demand for biosurfactants has beensteadily increasing and may eventually replace their chemically synthesized counterparts. Marine biosurfactants produced by some marine microorganisms have been paid more attention particularly for the bioremediation of the sea polluted by crude oil. The aim of this research isto screening microorganisms that produce biosurfactant from Pulau Laki, Kepulauan Seribu, Jakarta. The isolate which produce biosurfactant showed by clear ring zone on ONR7a crude oil medium. Three isolates were identified their characteristics based on the composition of nitrogenbase. Molecular identification based on 16S rRNA gene sequences indicated that bacteria had the highest similarity with Marinobacter satoriniensis strain NKSGI, Paracoccus sp and Pseudomonas sp.
Nitriles are widely manufactured and extensively used by chemical industries as synthesis intermediates. Although these compounds are generally highly toxic, due to their cyano functional group, they can be used by some microorganisms as carbon and/or nitrogen sources. Nitrilase catalyzes the direct cleavage of nitriles to the corresponding acids and ammonia, where as nitrile-hydratase catalyzes the hydratation of nitriles to amides. Applications of these nitrile-converting enzymes are now increasingly recognized for the production of several pharmaceutically important compounds and fine chemicals. By virtue of their capability to eliminate highly toxic nitriles, the enzymes also play a significant role in protecting the environment. Accordingly, it is very important to find microorganisms that have a great capacity to utilize or degrade nitriles. Recently, a bacterial isolate TPIK which shows high nitrile degrading activity has been isolated. The strain was isolated from tailing pond of gold mine activity by selective enrichment methods. TPIK was shown to be capable of degrading high concentrations of nitrile (up to approx. 1 M acetonitrile). Colonies of TPIK are light orange in colour and have irregularly round wrinkles. The cells of TPIK are non-spore-forming, non motile and Gram-positive, but are Gram-variable in old cultures. The cells are rods and brached fillaments during the early growth phase and then fragmented into short rods and cocci. The taxonomic position of TPIK was clarified using molecular genetic methods. The phylogenetic tree showed that bacterial isolate TPIK falls within an evolutionary radiation comprising Rhodococcus species and is most closely related to the type strain of Rhodococcus pyridinivorans, sharing 99% 16S rDNA similarity. To the best of our knowledge, this was the first time that Rhodococcus pyridinivorans has been described as containing nitrile-degrading enzymes. Usually, this bacterial strain has been studied for its ability to degrade carcinogenic compounds, like pyridine.