Objective:In this study, the aim was to isolate and identify bacterial strains in crude oil, drilling fluid and waste mud pit samples collected from the same oil field, determine the petroleum biodegradation and find the most effective bacteria in the samples in petroleum biodegradation.Methods:The contents of crude oil, drilling fluid and waste mud pit samples were enriched in appropriate conditions. Upon identification of the isolated bacteria, the incubations in petroleum containing media were performed at 150 rpm at 30°C for 7 days. Petroleum biodegradations by bacteria were measured by using colorimetric, spectrophotometric and gravimetric methods.Results:were isolated from the crude oil sample;Conclusion:In literature, no study was encountered showing biodegradation efficiencies of

The objectives of this study were to determine and compare the petroleum biodegradation efficiencies of three different bacterial consortia adapted to oil field. For this purpose, petroleum-contaminated waste mud sample was enriched in Bushnell Haas medium with 1% petroleum. Six different bacterial strains (four Gram-positive and two Gram-negative) were isolated from the enriched sample, and bacterial strains were identified with phenotypic and genotypic analyses. Each bacterial strain was evaluated in terms of biodegradation capacities by colorimetric analysis with the DCPIP redox indicator. Petroleum biodegradation efficiencies of three different consortia were investigated by gravimetric and GC-MS analyses. Consortium 1, consisting of Bacillus subtilis, Leuconostoc mesenteroides, Bacillus halotolerans, Enterococcus casseliflavus; consortium 2, consisting of Klebsiella pneumoniae and Pannonibacter phragmitetus; consortium 3, consisting of Bacillus subtilis, Leuconostoc mesenteroides, Bacillus halotolerans, Enterococcus casseliflavus, Klebsiella pneumoniae and Pannonibacter phragmitetus, were used in petroleum biodegradation. According to the results of gravimetric analysis, biodegradation of petroleum was 48%, 77% and 82% for consortium 1, consortium 2 and consortium 3, respectively. The results of GC-MS analysis revealed that removal of long-chain n-alkanes (C 23-C 32) was in the range of 35-58% by consortium 1; 56-67% by consortium 2; and 63-74% by consortium 3. It was emphasized that consortium 2 was more effective in biodegradation of petroleum than consortium 1. This study clearly demonstrated that consortium 3 is most effective in biodegradation of petroleum. This is assumed to be due to the synergistic effect between Gram-positive and Gram-negative bacterial strains. Furthermore, consortium 3 has been found to be very successful despite the shorter incubation period compared to other consortia in the literature. In this context, it is believed that the use of consortium 3 will contribute to the bioremediation of petroleum on a large scale.

Ö Z E T P seudomonas aeruginosa suşları tarafından üretilen piyosiyanin karakteristik mavi-yeşil bir fenazin pigmentidir. Çalışmanın amacı, P. aeruginosa suşlarında en yüksek piyosiyanin üretiminin belirlenmesi ve piyosiyaninin Escherichia coli, Bacillus sp., Pseudomonas aeruginosa, Candida sp. and Aspergillus niger üzerindeki antimiktobiyal etkisinin araştırılmasıdır. Bu doğrultuda, piyosiyanin P. aeruginosa kültür süpernatanından özütlendi ve saflaştırıldı, ardından spektrofotometrik olarak ölçüldü. En yüksek piyosiyanin üretiminin idrar örneğinden izole edilen P. aeruginosa A10 suşunda ve en düşük piyosiyanin üretiminin batından izole edilen P. aeruginosa A1 suşunda olduğu belirlendi. Piyosiyaninin antimikrobiyal etkisinin belirlenmesinde 'Agar Kuyu Difüzyon' yöntemi uygulandı. Böylece, piyosiyanin Bacillus sp., Escherichia coli ve Candida sp., üzerinde etkili bir antimikrobiyal ajanken, P. aeruginosa ve A. niger üzerinde antimikrobiyal etkisi görülmedi. Ardından, agar kuyu yöntemi ile piyosiyanine duyarlı olduğu belirlenen suşlara 'Tüp Seyreltme Yöntemi' kullanıldı. Azalan piyosiyanin derişimleri ile Bacillus sp. and Candida sp. suşlarının üremesinde artış gözlendi. Anahtar KelimelerPseudomonas aeruginosa, Piyosiyanin, Antimikrobiyal Aktivite. A B S T R A C TP yocyanin is the characteristic blue-green phenazine pigment produced by Pseudomonas aeruginosa strains. The aim of our study is to determine the highest amount of pyocyanin production in P. aeruginosa strains and to investigate the antimicrobial effect of pyocyanin pigment on Escherichia coli, Bacillus sp., Pseudomonas aeruginosa, Candida sp. and Aspergillus niger. For this purpose, pyocyanin was extracted from P. aeruginosa culture supernatants and purified, and then it was measured by spectrophotometrically. P. aeruginosa A10 strain isolated from urine specimen was determined as the highest amount of pyocyanin producer and P. aeruginosa A1 strain isolated from abdomen was the lowest. The 'Agar Well Diffusion' method was carried out to determine the antimicrobial effect of pyocyanin. Accordingly, pyocyanin was effective as an antimicrobial agent on Bacillus sp., Escherichia coli and Candida sp., but there was no antimicrobial effect on P. aeruginosa and A. niger. After that 'Tube Dilution Method' was used on strains, which were determined as sensitive to pyocyanin with agar well diffusion method. An increase in the intensity of Bacillus sp. and Candida sp. strains' growth with decreasing the concentration of pyocyanin was observed.

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Ö ZG ünümüzde, esansiyel yağların antimikrobiyal etkilerine, özgün ve kompleks biyolojik potansiyelleri nedeniyle artan bir ilgi söz konusudur. Bu çalışmada esansiyel yağların önemi nedeniyle farklı antibiyotik direnç paternleri olan 8 farklı Pseudomonas aeruginosa suşuna karşı kekik ve biberiye yağlarının antimikrobiyal özelliklerinin araştırılması amaçlandı. Bu amaçla Kirby Bauer disk difüzyon yöntemi ile 11 antibiyotik için antibiyotik direnç analizi gerçekleştirildi. Suşlar %100 trimetoprim/sülfometaksazol ve tetrasiklin, %50 aztreonam, meropenem, imipenem dirençli olarak bulundu; diğer yandan suşlar piperasilin, seftazidim ve amikasine duyarlıdır. Esansiyel yağların antimikrobiyal potansiyellerinin belirlenmesi sonucunda, kekik yağı antimikrobiyal ajan olarak çok etkili bulundu. Fakat biberiye yağının yalnız iki P. aeruginosa suşuna etkili olduğu görüldü. Kekik yağı yüksek derişimlerde (1/2) daha etkili olarak bulunurken düşük derişimlerde (1/20) bile antimikrobiyal etki belirlendi. Literatürde esansiyel yağların çoklu ilaç dirençli P. aeruginosa üzerindeki antimikrobiyal etkinlikleri ile ilgili bazı çalışmalar olmasına rağmen bu çalışma kekik yağının 8 farklı antibiyotik grubuna dirençli olan çoklu ilaç dirençli P. aeruginosa suşuna karşı çok etkili bulunması nedeniyle diğerlerinden farklıdır. Sonuç olarak bu çalışma kekik yağının antimikrobiyal etkisi ile yakın gelecekte çoklu ilaç dirençli P. aeruginosa infeksiyonlarının tedavisi için kullanılabileceğini gösteriyor.

Objective: Fungi play an important role in the removal of hazardous organic compounds from the environment with their extracellular multiple enzyme systems. In the bioremediation processes, fungi act as a bioreactor by breaking down or are biosorbent by accumulating organic pollutants. Materials and Methods:The aim of this study was to investigate and to compare the biodegradation and biosorption capacities of different amounts of live and dead biomasses and different concentrations of culture supernatants of Aspergillus parasiticus NRRL:3386 with gravimetric, gas chromatography-mass spectrometry (GC/MS) and scanning electron microscope (SEM) analyses.Results: This study indicated that 1 g of live biomass degraded 80% of petroleum within 4-days of incubation. The cellfree culture supernatant was not as effective as the live biomass in petroleum degradation. The petroleum biosorption was achieved at over 50% by 1 g and 2.5 g; over 70% by 5 g and 7.5 g, and over 80% by 10 g of dead biomasses. The petroleum removal efficiencies of 2 g of live and 10 g of dead biomasses were over 80%. GC/MS analysis demonstrated that C 10 -C 18 n-alkanes (except C 11 and C 13 ) and C 11 , C 13 , C 19 -C 26 n-alkanes were degraded 47-77% and over 80%, respectively. The moststriking result was that C 27 -C 33 n-alkanes were efficiently degraded over 90% in a short incubation period. SEM analysis showed that gaps between fungal hyphae were clear and bright before biosorption of petroleum, whereas gaps between fungal hyphae were closed after biosorption of petroleum. Conclusion:The results clearly pointed out that A. parasiticus will make a significant contribution to advanced mycoremediation studies.