Efficacy of Amendments in TPH Removal during Bioremediation of Agricultural Crude Oil-polluted Soil

This study identified the efficacy of different amendments as biostimulants in bioremediation. This experiment was carried out for 4 weeks in the laboratory. One kilogram of pristine soil was spiked with one liter of crude oil in earthen pots, to each pot 10 grams of amendments were added and mixed thoroughly. The amendments used were poultry dropping (C-PD), cow dung (D-CD), N.P.K (E), and a control (A and B) setup undergoing natural attenuation. The microcosms’ initial physicochemical characteristics such as total organic nitrogen, pH, temperature, total organic carbon, total petroleum hydrocarbon (TPH), and polyaromatic hydrocarbon (PAH). The microbial enumeration was done for total heterotrophic bacteria (THB) and hydrocarbon utilizing bacteria (HUB). The molecular characterization of the pristine soil (A) and contaminated soil (B) was also done using the shotgun analysis. The THB of A and B was 1.3 x 107 and 2.1 x 102 while the HUB was 1.63 x 105 and 1.1 x 101on day 1 respectively. The THB of treatments during bioremediation at week 2 was 1.75 x 108, 1.89 x 108, 1.5 x 108 and 2.2 x 108 while at week 4, the THB was 1.90 x 108, 2.1 x 108, 2.20 x 108 and 2.25 x 108 while the HUB at week 2 was 1.20 x 105, 3.0 x 105, 2.5 x 105 and 1.98 x 105 while at week 4, the HUB was 2.0 x 106, 2.19 x 106, 2.46 x 106 and 2.1 x 106 for B, PD, CD ,and N.P.K respectively. The molecular characterization of A and B showed there was a higher microbial diversity in the contaminated soil than in the pristine soil. This study has shown that cow dung is more effective in the bioremediation of total petroleum hydrocarbon, and polyaromatic hydrocarbon in crude oil-contaminated soil.

Evaluation of Bacterial Biofilm as Biosensor for Detecting Phenol, Catechol, and 1,2-dihydroxynaphthalene

Monitoring of water quality from the presence of polyaromatic hydrocarbon (PAHs) compounds and its derivates are important for keeping the healthy aquatic environment. Some of those derivates are phenol and several related compounds sharing simmilar structures. This reseach aimed for the detection of those phenol and several similar compounds monitoring due to PAHs degradation. Three identified bacterial isolates of Pseudomonas aeruginosa, Staphylococcus sciuri, and Bacillus amyloliquifaciens were selected based on their phenol degradation characters. On physiological properties all three isolates were observed to degrade several hydrophobic substances such as for naphthalene and anthracene. Yet, genetic analysis indicated that the phenolic degradating oxygenase gene was detected only in the P. aeruginosa and S. sciuri. Applying those isolates for biofilm as biosensor showed a sufficient analytical performance such as their limit of detection between 0.1-0.5 μM.

Benzodithiophene Fused Cyclopentannulated Aromatics via a Palladium-Catalyzed Cyclopentannulation and Scholl Cyclodehydrogenation Strategy

We report the synthesis of a new class of cyclopenta-fused polyaromatic hydrocarbon (CP-PAH) incorporating fused benzodithiophene subunits. These CP-PAHs were prepared utilizing a two-step process involving a palladium catalyzed cyclopentannulation followed by a Scholl cyclodehydrogenation. This work broadens the scope of annulation chemistry by employing 1,2-bis(5-hexylthiophen-3-yl)ethyne and dibromoaryl derivatives based on anthracene, pyrene and perylene to give 4,4',4'',4'''-(cyclopenta[hi]aceanthrylene-1,2,6,7-tetrayl)tetrakis(2-hexylthiophene) , 4,4',4'',4'''-(dicyclopenta[cd,jk]pyrene-1,2,6,7-tetrayl)tetrakis(2-hexylthiophene) and 1,2,7,8-tetrakis(5-hexylthiophen-3-yl)-1,2,7,8-tetrahydrodicyclopenta[cd,lm]perylene. Scholl cyclodehydrogenation of the pendant thiophene units provided access to the -extended polyaromatic systems 2,5,11,14-tetrahexylrubiceno[5,4-b:6,7-b':12,11-b'':13,14-b''']tetrathiophene, 2,5,11,14-tetrahexyldithieno-[4,5:6,7]indeno[1,2,3-cd]dithieno[4,5:6,7]indeno-[1,2,3-jk]pyrenes, and 2,9,12,19-tetrahexyldithieno[4,5:6,7]indaceno[1,2,3-cd]dithieno[4,5:6,7]indaceno[1,2,3-lm]perylene that possess helicene-like fragments. The anthracene-based CP-PAH was contorted owing to [5]helicene-like arrangements while the pyrene and perylene-based systems were essentially planar. The fully conjugated small molecules give low optical gaps (1.7 - 2.1 eV) with broad light absorption. The HOMO and LUMO energies of the CP-PAHs were found to be in the range of -5.48 to -5.05 eV and -3.48 to -3.14 eV, respectively. Finally, the anthracene-based CP-PAH was found to be a p-type semiconductor when tested in an organic field effect transistor.

Benzodithiophene Fused Cyclopentannulated Aromatics via a Palladium-Catalyzed Cyclopentannulation and Scholl Cyclodehydrogenation Strategy

We report the synthesis of a new class of cyclopenta-fused polyaromatic hydrocarbon (CP-PAH) incorporating fused benzodithiophene subunits. These CP-PAHs were prepared utilizing a two-step process involving a palladium catalyzed cyclopentannulation followed by a Scholl cyclodehydrogenation. This work broadens the scope of annulation chemistry by employing 1,2-bis(5-hexylthiophen-3-yl)ethyne and dibromoaryl derivatives based on anthracene, pyrene and perylene to give 4,4',4'',4'''-(cyclopenta[hi]aceanthrylene-1,2,6,7-tetrayl)tetrakis(2-hexylthiophene) , 4,4',4'',4'''-(dicyclopenta[cd,jk]pyrene-1,2,6,7-tetrayl)tetrakis(2-hexylthiophene) and 1,2,7,8-tetrakis(5-hexylthiophen-3-yl)-1,2,7,8-tetrahydrodicyclopenta[cd,lm]perylene. Scholl cyclodehydrogenation of the pendant thiophene units provided access to the -extended polyaromatic systems 2,5,11,14-tetrahexylrubiceno[5,4-b:6,7-b':12,11-b'':13,14-b''']tetrathiophene, 2,5,11,14-tetrahexyldithieno-[4,5:6,7]indeno[1,2,3-cd]dithieno[4,5:6,7]indeno-[1,2,3-jk]pyrenes, and 2,9,12,19-tetrahexyldithieno[4,5:6,7]indaceno[1,2,3-cd]dithieno[4,5:6,7]indaceno[1,2,3-lm]perylene that possess helicene-like fragments. The anthracene-based CP-PAH was contorted owing to [5]helicene-like arrangements while the pyrene and perylene-based systems were essentially planar. The fully conjugated small molecules give low optical gaps (1.7 - 2.1 eV) with broad light absorption. The HOMO and LUMO energies of the CP-PAHs were found to be in the range of -5.48 to -5.05 eV and -3.48 to -3.14 eV, respectively. Finally, the anthracene-based CP-PAH was found to be a p-type semiconductor when tested in an organic field effect transistor.

Oxidation of a Mixture of Polyaromatic Hydrocarbons by a Mixed Culture of Hydrocarbon-Oxidizing Microorganisms

The possibility of biochemical oxidation of polyaromatic hydrocarbon mixtures (PAHs) by the mixed culture of hydrocarbon-oxidizing microorganisms (HOM) in a liquid medium and soil was investigated. The mixed HOM culture was represented by Pseudomonas stutzeri, Pseudomonas putida, Bacillus cereus, and Arthrobacter globiformis genera. It was shown that during HOM cultivation of the microorganisms under study in the liquid medium their number increases from 0.25·104 to 11·108 CFU/ml, which is accompanied by an increase in their oxygenase activity. All PAHs identified were subjected to oxidation from 11.3 to 100%. The results of experiments on biodegradation of PAHs under natural conditions have shown that for 60 days the total utilization of oil products in soils was on the average 65% of the initial contamination. This suggests the prospects for the use of the mixed HOM culture under study for effective biodegradation of PAHs polluting soil and waste waters.

Palaeobotanical and biomarker evidence for Early Permian (Artinskian) wildfire in the Rajmahal Basin, India

This study provides a combined analysis on the palynology, fossil charcoal and biomarkers of the subsurface coal deposits from a borehole RMB #2 drilled at the Dhulia Coal Block, Rajmahal Basin, India, in attempts to establish the chronology of sedimentation and to propose palaeobotanical as well as geochemical evidence for the occurrence of wildfires in these sediments. The palynological investigation suggests a Scheuringipollenites barakarensis palynoassemblage from the lower Barakar Formation, dated as Artinskian (Early Permian) in age. This assemblage reveals the dominance of Glossopteridales and sub-dominance of taxa belonging to Cordaitales and Coniferales. Fossil charcoal in sediments is usually recognized as a direct indicator for the occurrence of palaeo-wildfires. More data involving the anatomical features of fossil charcoal analyzed by Field Emission Scanning Electronic Microscope broaden our knowledge on Early Permian wildfires from the peninsula of India. The studied macroscopic charcoal fragments exhibit anatomical details such as homogenized cell walls, uniseriate simple and biseriate alternate pitting on tracheid walls and rays of varying heights pointing to a gymnospermous wood affinitity. The excellent preservation of charcoal fragments, shown by their large sizes and almost unabraded edges, suggests a parautochthonous origin. The embedded biomarker study performed for charcoal sediments and its characterization demonstrate the presence of n-alkanes, isoprenoids, terpenoids and aromatic compounds. A bimodal distribution pattern of n-alkanes with a Cmax at n-C25 is identified. Diterpenoids and pentacyclic terpenoids are identified, indicating the input of an early conifer vegetation and bacterial activity, respectively. The identified polyaromatic hydrocarbon (PAH) compounds, together with the charcoal fragments, clearly suggest that repeated wildfire events occurred during the deposition of these Artinskian sediments in the Rajmahal Basin.

PEMANFAATAN KULIT JAGUNG SEBAGAI BAHAN PEMBUATAN BIODEGRADABLE FOAM

Kemasan makanan yang digunakan sebagian besar adalah jenis kemasan sekali pakai, salah satunya adalah styrofoam. Penggunaan styrofoam yang semakin banyak dapat menyebabkan peningkatan jumlah sampah yang tidak dapat terdegradasi. Pembakaran styrofoam juga berbahaya karena menghasilkan gas berbahaya seperti styrene, polyaromatic hydrocarbon (PAHs), hydro cloro flouro carbon (HCFC), dan karbon monoksida (CO). Salah satu alternatif untuk mengurangi penggunaan styrofoam adalah menggunakan kemasan makanan yang ramah lingkungan seperti biodegradable foam (biofoam). Bahan yang digunakan dalam penelitian ini adalah limbah kulit jagung lokal Indonesia, jagung mutiara. Tujuan dari penelitian ini yaitu untuk mengetahui karakteristik biofoam yang terbuat dari kulit jagung dan persentase konsentrasi kulit jagung yang terbaik untuk pembuatan biofoam dalam penelitian ini. Metode dari penelitian ini adalah metode eksperimen dengan variasi konsentrasi kulit jagung 3%, 5%, dan 7%. Hasil biofoam yang terbaik adalah dengan konsentrasi kulit jagung 3% dengan nilai hasil uji daya serap air 13,93%, tingkat biodegradasi 6,22%, kuat tarik 2,63 N/mm2, dan kuat tekan 5,00 N/mm2.

Phenanthrene impacts zebrafish cardiomyocyte excitability by inhibiting IKr and shortening action potential duration

Air pollution is an environmental hazard that is associated with cardiovascular dysfunction. Phenanthrene is a three-ringed polyaromatic hydrocarbon that is a significant component of air pollution and crude oil and has been shown to cause cardiac dysfunction in marine fishes. We investigated the cardiotoxic effects of phenanthrene in zebrafish (Danio rerio), an animal model relevant to human cardiac electrophysiology, using whole-cell patch-clamp of ventricular cardiomyocytes. First, we show that phenanthrene significantly shortened action potential duration without altering resting membrane potential or upstroke velocity (dV/dt). L-type Ca2+ current was significantly decreased by phenanthrene, consistent with the decrease in action potential duration. Phenanthrene blocked the hERG orthologue (zfERG) native current, IKr, and accelerated IKr deactivation kinetics in a dose-dependent manner. Furthermore, we show that phenanthrene significantly inhibits the protective IKr current envelope, elicited by a paired ventricular AP-like command waveform protocol. Phenanthrene had no effect on other IK. These findings demonstrate that exposure to phenanthrene shortens action potential duration, which may reduce refractoriness and increase susceptibility to certain arrhythmia triggers, such as premature ventricular contractions. These data also reveal a previously unrecognized mechanism of polyaromatic hydrocarbon cardiotoxicity on zfERG by accelerating deactivation and decreasing IKr protective current.