Biodegradation of aliphatic and aromatic hydrocarbons using the filamentous fungus Penicillium sp. CHY-2 and characterization of its manganese peroxidase activity

The aim of this work was to study the potential of the non-lignolytic filamentous fungus Penicillium sp. CHY-2, isolated from Antarctic soil, for the biodegradation of eight different aliphatic and aromatic hydrocarbons such as octane, decane, dodecane, ethylbenzene, butylbenzene, naphthalene, acenaphthene, and benzo[a]pyrene. Among all the compounds, CHY-2 showed the highest level of degradation for decane (49.0%), followed by butylbenzene (42.0%) and dodecane (33.0%), and lower levels of degradation for naphthalene (15.0%), acenaphthene (10.0%), octane (8.0%), ethylbenzene (4.0%), and benzo[a]pyrene (2.0%) at 20 °C. The addition of carbon sources such as glucose (5 g L−1) and Tween-80 (5 g L−1) enhanced decane degradation by about 1.8-fold and 1.61-fold respectively at 20 °C. The metabolites produced during the degradation of decane were identified by gas chromatography-mass spectrometry (GC-MS). Furthermore, the enzyme manganese peroxidase (MnP) from CHY-2 was purified. MnP was found to consist of monomers with a molecular mass of 36 kDa. The purified MnP had an optimum pH of 5.0 and temperature of 30 °C. The Km and Vmax values of MnP towards Mn2+ were 1.31 μM and 185.19 μM min−1 respectively. These results indicated that the strain CHY-2 can be used for the degradation of hydrocarbons and could have promising applications in treatment of hydrocarbon contaminated sites

Isolation and characterization of a biosurfactant-producing heavy metal resistant Rahnella sp. RM isolated from chromium-contaminated soil

Objective of the study was to isolate heavy metal resistant bacteria from chromium-contaminated subsurface soil and investigate biosurfactant production and heavy metal bioremediation. Based on 16S rRNA gene sequence and phylogenetic analysis, the isolate was identified as Rahnella sp. RM. The biosurfactant production by heavy metal resistant Rahnella sp. RM was optimized using Box- Behnken design (BBD). The maximum emulsification activity was obtained 66% at 6% soybean meal in pH 7.0 and 33.5°C. The biosurfactant was characterized using Field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FT-IR) and matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF). The highest metal removal rates using the biosurfactant were found 74.3, 72.5, and 70.1%, respectively, at the 100 mg/L amended flasks at 48 h. This study indicated the biosurfactant from heavy metal resistant Rahnella sp. RM could be used as a potential tool to remediate the metals in contaminated environments

Iatrogenic Hepatic Pneumovenogram

Accidental air entry during central venous catheterization is a preventable iatrogenic complication that can cause venous air embolism (VAE). Many cases of VAE are subclinical with no adverse outcome and thus go unreported. Usually, when symptoms are present, they are nonspecific, and a high index of clinical suspicion of possible VAE is required to prompt investigations and initiate appropriate therapy. Occasionally large embolism can lead to life-threatening acute cor pulmonale, asystole, sudden death, and arterial air embolism in the presence of shunt or patent foramen ovale. This paper discusses VAE during emergency central line placement and the diagnostic dilemma that it can be created in critically ill patients. All necessary precautions have to be strictly followed to prevent this iatrogenic complication

Emerging contaminants of high concern for the environment: Current trends and future research

Wastewater is contaminated water that must be treated before it may be transferred into other rivers and lakes in order to prevent further groundwater pollution. Over the last decade, research has been conducted on a wide variety of contaminants, but the emerging contaminants are those caused primarily by micropollutants, endocrine disruptors (EDs), pesticides, pharmaceuticals, hormones, and toxins, as well as industrially-related synthetic dyes and dye-containing hazardous pollutants. Most emerging pollutants did not have established guidelines, but even at low concentrations they could have harmful effects on humans and aquatic organisms. In order to combat the above ecological threats, huge efforts have been done with a view to boosting the effectiveness of remediation procedures or developing new techniques for the detection, quantification and efficiency of the samples. The increase of interest in biotechnology and environmental engineering gives an opportunity for the development of more innovative ways to water treatment remediation. The purpose of this article is to provide an overview of emerging sources of contaminants, detection technologies, and treatment strategies. The goal of this review is to evaluate adsorption as a method for treating emerging pollutants, as well as sophisticated and cost-effective approaches for treating emerging contaminants

Genetic variability among _Coleus sp_ studied by RAPD banding pattern analysis

Genetic improvement of the medicinal plants depends upon the existence, nature and extent of the genetic variability available for manipulation. Genetic analysis with RAPD markers has been extensively used to determine genetic diversity among _Coleus sp_ and to identify the best quality for human consumption for its medicinal purpose. The objectives of the present study were to assess molecular variation among _C.amboinicus_, _C.aromaticus_ and _C.forskohlii_. and to determine the level of genetic similarity among them. We performed random amplification of polymorphic DNA (RAPD) analysis on three strains of _Coleus sp_. Random primers were used for the PCR. Electrophoresis on denaturing acrylamide gels improved RAPD reproducibility and increased the band number. The primer OPW 6 and OPW 7 gave reproducible results and the band profiles

Microbially-induced Carbonate Precipitation for Immobilization of Toxic Metals

Rapid urbanization and industrialization resulting from growing populations contribute to environmental pollution by toxic metals and radionuclides which pose a threat to the environment and to human health. To combat this threat, it is important to develop remediation technologies based on natural processes that are sustainable. In recent years, a biomineralization process involving ureolytic microorganisms that leads to calcium carbonate precipitation has been found to be effective in immobilizing toxic metal pollutants. The advantage of using ureolytic organisms for bioremediating metal pollution in soil is their ability to immobilize toxic metals efficiently by precipitation or coprecipitation, independent of metal valence state and toxicity and the redox potential. This review summarizes current understanding of the ability of ureolytic microorganisms for carbonate biomineralization and applications of this process for toxic metal bioremediation. Microbial metal carbonate precipitation may also be relevant to detoxification of contaminated process streams and effluents as well as the production of novel carbonate biominerals and biorecovery of metals and radionuclides that form insoluble carbonates.</p

Utilization of Waste Peels for Enhanced Production of Bioplastics by Enterococcus fecium - A Green Initiative

From ancient times, plastics have become a part and parcel of human life. Though it has become indispensable, yet disposal has created a problem and has become an environmental concern. The introduction of bioplastics is thought to be a solution to address the problem. However, isolation and characterization of microbes with bioplastic production potential are being investigated. Several sources were sought after to screen for PHB producing bacteria and in such attempt, we have initiated to isolate bacteria producing PHB from curd sample. Such bacteria was cultured and identified through 16SrRNA sequencing. To replace expensive conventional media, peels of banana and beet roots were used to culture the bacterium without any chemical supplementation. This has been reported for the first time. The PHB produced by the bacterium was extracted following standard protocol and was confirmed by GC-MS analysis. The bioplastic film was prepared using PHB powder extracted and biodegradation and solubility study was conducted. Hence, utilization of waste vegetable and fruit peels serve as carbon source enhancing the bacterial growth, leading to the production of PHB in nitrogen-deficient condition. In future, the waste peels could be utilized as medium for PHB production, which also addresses the problem of pollution

Bioremediation of heavy metals using an endophytic bacterium Paenibacillus sp. RM isolated from the roots of Tridax procumbens

The aim of the present study was to assess the bioremediation potential of endophytic bacteria isolated from roots of Tridax procumbens plant. Five bacterial endophytes were isolated and subsequently tested for minimal inhibitory concentration (MIC) against different heavy metals. Amongst the five isolates, strain RM exhibited the highest resistance to copper (750 mg/l), followed by zinc (500 mg/l), lead (450 mg/l), and arsenic (400 mg/l). Phylogenetic analysis of the 16S rDNA sequence suggested that strain RM was a member of genus Paneibacillus. Strain RM also had the capacity to produce secondary metabolites, indole acetic acid, siderophores, 1-aminocyclopropane-1-carboxylate (ACC) deaminase, and biosurfactant and solubilize phosphate. The growth kinetics of strain RM was altered slightly in the presence of metal stress. Temperature and pH influenced the metal removal rate. The results suggest that strain RM can survive under the high concentration of heavy metals and has been identified as a potential candidate for application in bioremediation of heavy metals in contaminated environments