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Isolation and Detection of MTBE Degrading Bacteria  [PDF]
A. Mesdaghinia,S. Rezaie,M. Shariat,S. Nasseri
Pakistan Journal of Biological Sciences , 2005,
Abstract: This research was carried out to isolate and identify degrading microorganisms of MTBE in the soil samples taken from the adjacent ground of lead-free gasoline storage tanks as well as from drainage water of MTBE and gasoline storage tanks. Water and soil samples were prepared and microorganisms were inoculated and then harvested from mineral salt media. After several passages within 200 days, microorganisms capable of using MTBE as carbon and energy source were isolated. Isolated microorganisms inoculated in common culture media including R2A agar and BHI were identified as Pseudomonas putida, Comamonas, Alcaligenes, Bacillus and Micrococcus by specific kit of epi.
Hydrocarbon Degrading Bacteria: Isolation and Identification
Lies Indah Sutiknowati
Makara Seri Sains , 2007,
Abstract: There is little information how to identify hydrocarbon degrading bacteria for bioremediation of marine oil spills. We have used gravel which contaminated oil mousse from Beach Simulator Tank, in Marine Biotechnology Institute, Kamaishi, Japan, and grown on enrichment culture. Biostimulation with nutrients (N and P) was done to analyze biodegradation of hydrocarbon compounds: Naphthalene, Phenanthrene, Trichlorodibenzofuran and Benzo[a]pyrene. Community of bacteria from enrichment culture was determined by DGGE. Isolating and screening the bacteria on inorganic medium contain hydrocarbon compounds and determination of bacteria by DAPI (number of cells) and CFU. DNA was extracted from colonies of bacteria and sequence determination of the 16S rDNA was amplified by primers U515f and U1492r. Twenty nine strains had been sequence and have similarity about 90-99% to their closest taxa by homology Blast search and few of them have suspected as new species.
Extraction and Characterization of Oil Degrading Bacteria  [PDF]
Khalida Khan,M. Naeem,M. Javed Arshed,M. Asif
Journal of Applied Sciences , 2006,
Abstract: The present study was conducted to determine the isolation, identification and characterization of efficient oil degrading bacterial strains and to study the effect of different concentration of crude oil on the growth of bacterial strain. Two samples soil and water were collected from the crude oil contaminated areas for the isolation and characterization of efficient crude oil degrading strains. Sub culturing technique was employed to isolate 43 numerically dominant bacteria that had the ability to grow on 1.0% crude oil on nutrient agar plates. The isolates were then subjected to different concentrations of crude oil on nutrient agar, mineral salt agar media containing Phosphorous, Nitrogen and trace elements with glucose (PNTG) and without glucose (PER). These isolates showed rich growth on nutrient agar media along with crude oil. Out of 43 isolates 7 were able to grow up to 2.0% crude oil and were named as AA-1 to AA-7. These strains were also able to grow on mineral salt agar media with and without glucose but with different susceptibility to different concentrations of crude oil. Finally 3 prospective strains AA-1, AA-2 and AA-3 were selected for further studies. These strains exhibited good growth in PNTG containing 1.0% crude oil as evident by increase in Optical Density (OD) after every 24 h for five days. These isolated strains were identified by morphological and biochemical tests and were found to belong to genus Bacillus. These strains were subjected to shake flask transformation of crude oil in mineral salt media (PNTG) with glucose for 15 days. Marked change in crude oil colour was observed for these isolates, indicating their biodegradative ability. These isolated strains were able to use crude oil as the sole source of carbon and energy even under stressed environmental conditions. Thus these strains have bright potential for biodegradation of crude oil resulting in clean up of oil spills.
Contribution of Gut Bacteria to Liver Pathobiology  [PDF]
Gakuhei Son,Michael Kremer,Ian N. Hines
Gastroenterology Research and Practice , 2010, DOI: 10.1155/2010/453563
Abstract: Emerging evidence suggests a strong interaction between the gut microbiota and health and disease. The interactions of the gut microbiota and the liver have only recently been investigated in detail. Receiving approximately 70% of its blood supply from the intestinal venous outflow, the liver represents the first line of defense against gut-derived antigens and is equipped with a broad array of immune cells (i.e., macrophages, lymphocytes, natural killer cells, and dendritic cells) to accomplish this function. In the setting of tissue injury, whereby the liver is otherwise damaged (e.g., viral infection, toxin exposure, ischemic tissue damage, etc.), these same immune cell populations and their interactions with the infiltrating gut bacteria likely contribute to and promote these pathologies. The following paper will highlight recent studies investigating the relationship between the gut microbiota, liver biology, and pathobiology. Defining these connections will likely provide new targets for therapy or prevention of a wide variety of acute and chronic liver pathologies. 1. Introduction Receiving approximately 70% of its blood supply from the portal vein which is the direct venous outflow of the intestine, the liver is continually exposed to gut-derived factors including bacteria and bacterial components. To combat this influx, the liver contains a large number of resident immune cells including macrophages (i.e., the Kupffer cell), lymphocytes, natural killer cells, dendritic cells, and B cells. Together, these immune cell populations in conjunction with other nonparenchymal cells including endothelial cells and stellate cells orchestrate a controlled and organized response to these potentially highly inflammatory factors. However, when normal liver physiology is disrupted and inflammatory cells are activated, gut-derived factors likely augment or exacerbate certain liver diseases leading to enhanced tissue damage and propagation of inflammation. Thus, understanding the mechanisms both of control and of activation by gut-derived factors as well as the functionality of the gut barrier are critical to the development of new therapeutic modalities to treat or prevent acute and chronic liver diseases such as viral hepatitis, alcoholic liver disease, and/or liver cancer. The current paper will provide an overview of gut bacterial populations, gut barrier function, and the potential interactions of gut bacteria with acute and chronic liver disease. 2. The Gut Microbiome The human intestine provides residence to bacteria, a number which dwarfs the total
Isolation and Identification of Quercetin Degrading Bacteria from Human Fecal Microbes  [PDF]
Zhichao Zhang, Xichun Peng, Shaoting Li, Ning Zhang, Yong wang, Hua Wei
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0090531
Abstract: Quercetin has a wide range of biological properties. The gut microflora can often modulate its biological activity and their potential health effects. There still is a lack of information about gut bacteria involving in this process. The strains of gut microbes from human feces that can transform quercetin were isolated and identified by in vitro fermentation. The results showed that Escherichia coli, Stretococcus lutetiensis, Lactobacillus acidophilus, Weissella confusa, Enterococcus gilvus, Clostridium perfringens and Bacteroides fragilis have the various ability of degrading quercetin. Among them, C. perfringens and B. fragilis were discovered to have the strongest ability of degrading quercetin. Additionally, quercetin can't inhibit the growth of C. perfringens. In conclusion, many species of gut microbiota can degrade quercetin, but their ability are different.
Identification of Petroleum Degrading Bacteria and Construction of Petroleum Degrading Agent
Xingling Tao, Yabin Zhan, Tao Jiang, Chuanjiong Hu
Open Access Library Journal (OALib Journal) , 2019, DOI: 10.4236/oalib.1105335
The aim of this study is to construct petroleum degrading agent (PDA) which can effectively degrade oil. By enrichment, domestication, and separation of culture from the soil sample of Qianjiang Guanghua Oilfield, the pure culture of three petroleum degrading bacteria G-40, G-53, and G-94 was identified from the medium supplemented with oil, which served as the sole source of carbon. The species of G-40 and G-53 were preliminarily identified and classified by morphological observation, physiological and biochemical determination, and sequence analyses of 16S rDNA. The species of G-94 was preliminarily identified and classified by morphological observation, physiological and biochemical determination, and sequence analyses of ITS rDNA. The optimal inoculation proportion of these three bacteria strains and bran proportion in composition of PDA were determined through orthogonal test. G-40, G-53, and G-94 were isolated and identified as Brevibacillus laterosporus, Tsukamurella inchonensis, and Candida tropicalis, respectively. To construct petroleum degrading agent, the optimum inoculation proportion of the three bacteria strains was A1B3C3 (G-40:G-53:G-94 = 1:4:4); and the optimum proportion of bran was D1E1F2 (soybean meal:corn flour:bran = 1:1:2). The oil removal rate of the constructed petroleum degrading agent reached to 42.32% on day 10 under the optimal proportion of bacteria inoculation and bran composition. Petroleum degrading bacteria can effectively degrade petroleum for its own growth. This study identified three petroleum degrading bacteria strains and proposed a petroleum degrading agent by studying the optimal inoculation proportion of the three bacterial strains and the accompanying bran. Our research could provide potential microbial resources for bioremediation of petroleum-contaminated soil.
Communities of microbial eukaryotes in the mammalian gut within the context of environmental eukaryotic diversity  [PDF]
Laura Wegener Parfrey,William A. Walters,Christian L. Lauber,Jose C. Clemente,Clotilde Teiling,Chinnappa Kodira,Julie Brunelle,Noah Fierer,Jack A. Gilbert
Frontiers in Microbiology , 2014, DOI: 10.3389/fmicb.2014.00298
Abstract: Eukaryotic microbes (protists) residing in the vertebrate gut influence host health and disease, but their diversity and distribution in healthy hosts is poorly understood. Protists found in the gut are typically considered parasites, but many are commensal and some are beneficial. Further, the hygiene hypothesis predicts that association with our co-evolved microbial symbionts may be important to overall health. It is therefore imperative that we understand the normal diversity of our eukaryotic gut microbiota to test for such effects and avoid eliminating commensal organisms. We assembled a dataset of healthy individuals from two populations, one with traditional, agrarian lifestyles and a second with modern, westernized lifestyles, and characterized the human eukaryotic microbiota via high-throughput sequencing. To place the human gut microbiota within a broader context our dataset also includes gut samples from diverse mammals and samples from other aquatic and terrestrial environments. We curated the SILVA ribosomal database to reflect current knowledge of eukaryotic taxonomy and employ it as a phylogenetic framework to compare eukaryotic diversity across environment. We show that adults from the non-western population harbor a diverse community of protists, and diversity in the human gut is comparable to that in other mammals. However, the eukaryotic microbiota of the western population appears depauperate. The distribution of symbionts found in mammals reflects both host phylogeny and diet. Eukaryotic microbiota in the gut are less diverse and more patchily distributed than bacteria. More broadly, we show that eukaryotic communities in the gut are less diverse than in aquatic and terrestrial habitats, and few taxa are shared across habitat types, and diversity patterns of eukaryotes are correlated with those observed for bacteria. These results outline the distribution and diversity of microbial eukaryotic communities in the mammalian gut and across environments.
Aerobic dehalogenation activities of two petroleum degrading bacteria
O Igbinosa, OS Ajisebutu, IA Okoh
African Journal of Biotechnology , 2007,
Abstract: Two petroleum degrading bacteria were screened for 2,4-dichlorophenyacetic acid (2,4-D) degrading abilities and assessed for their dechlorination potentials. The bacterial isolates were previously identified to be Corynebacterium sp. (SOGU16) and Achromobacter sp. (SOGU11). Axenic cultures of the isolates metabolise 2,4-D as the sole source of carbon and energy. The optimum pH for dioxygenase specific activities was between 7.6 and 8.0 and the optimum temperature was between 30 and 35°C. The cell-free extracts of the cultures in the 2,4-D demonstrated biological degradation of the 2,4-D compound. The observations made in this study are sufficient to conclude that the isolates obtained have reasonable potentials for application in bioremediation of both petroleum and 2, 4-D contaminated sites.
Screening and Application of Phthalic Acid Degrading Bacteria  [PDF]
Wenhao Li, Xiaoqiong Yang, Gaodong Li, Cheng Li, Yuhan Xu, Jingguo Sun, Changjun Wang, Shunyi Li, Xin Ma, Qin Wang, Shouwen Chen, Jun Yu, Yong Yang
Open Journal of Applied Sciences (OJAppS) , 2018, DOI: 10.4236/ojapps.2018.812047
Abstract: O-phthalic acid is a kind of important pollutant, which accumulates in the environment with the extensive use of plastics and other products. Meanwhile, phthalic acid is one of the high content of allelopathic autotoxic substances secreted by tobacco. The accumulation of phthalic acid in soil is an important cause of tobacco continuous cropping effect. In order to degrade phthalic acid accumulated in environment, the barrier effect of tobacco continuous cropping caused by phthalic acid accumulation in soil can be removed. A strain capable of degrading phthalic acid was isolated from sludge of sewage treatment plant and compared with 16 s DNA. The homology between this strain and Enterobacter sp. is 99%. The optimum growth conditions are as follows: pH7 at 30°C, 500 mg/L of o-phthalic acid, inoculation concentration ≥ 1.2% and its highest degradation rate of o-phthalic acid is 74%. The results of pot experiment showed that the degradation efficiency of o-phthalic acid in soil was about 40%, which alleviated the inhibitory effect of o-phthalic acid accumulation on tobacco growth.
Obesity as a Consequence of Gut Bacteria and Diet Interactions  [PDF]
Katerina Kotzampassi,Evangelos J. Giamarellos-Bourboulis,George Stavrou
ISRN Obesity , 2014, DOI: 10.1155/2014/651895
Abstract: Obesity is a major public health concern, caused by a combination of increased consumption of energy-dense foods and reduced physical activity, with contributions from host genetics, environment, and adipose tissue inflammation. In recent years, the gut microbiome has also been found to be implicated and augmented research in mice and humans have attributed to it both the manifestation and/or exacerbation of this major epidemic and vice versa. At the experimental level, analysis of fecal samples revealed a potential link between obesity and alterations in the gut flora (drop in Bacteroidetes and increase in Firmicutes), the specific gut microbiome being associated with the obese phenotype. Conventionally raised mice were found to have over 40% more total body fat compared with those raised under germ-free conditions, while conventionalization of germ-free mice resulted in a significant increase in total body fat. Similarly, the sparse data in humans supports the fact that fat storage is favoured by the presence of the gut microbiota, through a multifaceted mechanism. Efforts to identify new therapeutic strategies to modulate gut microbiota would be of high priority for public health, and to date, probiotics and/or prebiotics seem to be the most effective tools. 1. Introduction Obesity is a major public health concern, threatening both the industrialized and the developing countries, largely in parallel to the adoption of a “modern”/Western-type lifestyle. It results from a long-term disbalance between energy intake and expenditure, that is, increased consumption of more energy-dense, nutrient-poor foods containing high levels of sugar and saturated fats in combination with reduced physical activity [1]. However, the mechanisms underlying obesity seem to be far from the long-held belief in caloric intake and lifestyle factors. It is becoming evident that obesity and its causes are significantly more complex than previously thought, with contributions from host genetics, environment, diet and lifestyle, and systemic and adipose tissue inflammation [2]. Obesity is now characterized by a cluster of important chronic metabolic disorders, including insulin resistance, type 2 diabetes, fatty liver disease, atherosclerosis, hypertension, and hypercholesterolemia, and by a low grade of systemic inflammation [3], being the cause of exacerbation of all the above and leading to increased morbidity and mortality. Moreover, obesity is detrimental to the quality of life as a whole and implies high health costs as a consequence of its associated morbidities. In recent
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