Environmental Science
D. Pringgenies; W. Ari Setyati; F. Feliatra; D. Ariyanto
Abstract
BACKGROUND AND OBJECTIVES: Mangroves are known to contain tannins, flavonoids, and quinones, which have the potential to be antibacterial, effective even against multidrug-resistant bacteria. Mangroves also have antifungal and antiviral properties. Although, mangroves are known for their use as medicinal ...
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BACKGROUND AND OBJECTIVES: Mangroves are known to contain tannins, flavonoids, and quinones, which have the potential to be antibacterial, effective even against multidrug-resistant bacteria. Mangroves also have antifungal and antiviral properties. Although, mangroves are known for their use as medicinal ingredients, information regarding symbiont bacteria’s antibacterial and antifungal potential is still scarce. Therefore, this study aimed to examine symbiont bacteria in the fruit and leaves of Xylocarpus granatum as additional raw materials for anti-acne cosmetic creams and moisturisers.METHODS: Symbiont bacteria were isolated using the pour plate method through Zobell 2216E and incubated for 2 x 24 hours at 27.5 Celcius degree. Afterwards, 13 isolates were successfully isolated and characterised based on their morphology. Further, everal tests were conducted, including the antibacterial test, antifungal test, molecular identification, and gas chromatography-mass spectrometry. The pathogenic bacteria used in the antibacterial test were Staphylococcus aureus, Vibrio harveyi, and Vibrio alginolyticusFINDINGS: The antibacterial test results showed that eight isolates were capable of producing an inhibition zone against S. aureus, seven isolates were positive for antibacterial activity against Vibrio harveyi, and 10 isolates were positive for antibacterial activity against Vibrio alginolyticus. The pathogenic fungi used in the antifungal test were Malassezia furfur and Candida albicans. The antifungal test results demonstrated that six isolates could produce inhibition zones against Malassezia furfur and Candida albicans. Furthermore, molecular identification was carried out on six potential isolates based on the antibacterial and antifungal tests, which were X2.52, X1.65, X1.64, X1.53, X1.54, and X1.63. The molecular identification results revealed the occurrence of four species in the Xylocarpus granatum mangroves, namely, Sinomicrobium oceani, Proteus mirabilis, Pseudomonas khazarica, and Alcaligenes aquatilis.CONCLUSION: The study found that the mangrove symbiont bacteria had antibacterial and antifungal potential. The compound with the highest concentration in six isolates was 9-octadecenoic acid, methyl ester. This type of content has antibacterial potential and is also predicted to have antifungal potential.
Environmental Science
G. Manjarrez Paba; R. Baldiris Ávila; D. Baena Baldiris
Abstract
BACKGROUND AND OBJECTIVES:The objective of this study isto present a description of the main characteristics of azo dyes and the different treatment methods used to remove them from water. There is a special emphasis given to the benefits associated with biological treatment, predominantly those related ...
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BACKGROUND AND OBJECTIVES:The objective of this study isto present a description of the main characteristics of azo dyes and the different treatment methods used to remove them from water. There is a special emphasis given to the benefits associated with biological treatment, predominantly those related to the use of bacteria, which has to do with its competitive advantages over other microorganisms in the dye degradation processes.METHODS: The topic to be addressed was first defined through workshops with the research group. The literature review was carried out following several inclusion/exclusion criteria: the year of publication, as the selection was limited to studies published between 2010 and 2020, the focus of the investigation, which had to be related to the efficiency of different techniques for the remediation of ecosystems contaminated with azo dyes and, lastly, that the studies also discussed the use of environmental bacteria in dye degradation processes.FINDING: The efficiency of bacteria to degrade azo dyes ranges from 63-100%, the most efficient being: Marinobacter sp, Sphingobacterium sp, Enterococcus faecalis, Enterococcus casseliflavus. The bacteria that, reportedly, have greater efficiency for simultaneously removing the dye-metal complex are Bacillus circulans and Acinetobacter junii.CONCLUSION: Traditional strategies for the treatment of effluents contaminated with azo dyes are limited to physical and chemical processes that have a high energy and economic cost. For these reasons, current challenges are focused on the use of environmental bacteria capable of transforming dyes into less toxic compounds.
Environmental Science
J. Petersen; C.P. Colon; J.L. Joyner
Abstract
Plumb Beach, Brooklyn, New York in USA is an important horseshoe crab breeding and nursery ground that has experienced substantial anthropogenic influence, including pollution, erosion and subsequent restoration. Since little is known about the relationship between sediment microbial communities and ...
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Plumb Beach, Brooklyn, New York in USA is an important horseshoe crab breeding and nursery ground that has experienced substantial anthropogenic influence, including pollution, erosion and subsequent restoration. Since little is known about the relationship between sediment microbial communities and juvenile horseshoe crab survival, next generation sequencing was used to characterize and compare the sediment microbiome of three distinct areas of Plumb Beach:- a tidal creek with abundant juveniles, East Beach with moderate number of juveniles, and West Beach- a highly disturbed area where juvenile crabs are rarely seen. The microbiome of juvenile crab intestinal content (both dissected gut content and fecal flush content) from the tidal creek site was also examined. The results showed that in our 2017 survey, the overall dominant sediment orders at all beach sites were Vibrionales (30%), Flavobacteriales (22%) and Alteromonadales (21%). Although alpha diversity was similar among the three beach sites, Bray-Curtis distances assessed by Permanova revealed significant differences in Beta diversity, with a unique microbial assemblage found in the tidal creek. Both crab gut and fecal flush samples did not sequence well, showing low species diversity and very high variability. This study is the first to use next generation sequencing to characterize Plumb Beach sediment microbes and the first attempt to examine the gut microbiome of juvenile horseshoe crabs. This information will contribute to understanding the relationships between sediment microbial assemblages and juvenile crab populations within this important urban habitat.
Environmental Science
P. Bhuyar; M.H. Rahim; S. Sundararaju; G.P. Maniam; N. Govindan
Abstract
Seaweeds can produce variety of bioactive components for the benefits of humans. Malaysia is one of the countries to produce red seaweeds, which are popular secondary metabolites. Kappaphycus species, largest tropical red algae exhibit the high growth rate. It was reported that its biomass can grow double ...
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Seaweeds can produce variety of bioactive components for the benefits of humans. Malaysia is one of the countries to produce red seaweeds, which are popular secondary metabolites. Kappaphycus species, largest tropical red algae exhibit the high growth rate. It was reported that its biomass can grow double in just 15 to 30 days. Therefore, this investigation emphasized on two extraction methods such as hot water and ethanolic Soxhlet extraction to extract the bioactive compounds from Kappaphycus alvarezii. Both of theseextractions were screened to produce antimicrobial and antioxidants compounds. Total phenolic content and ferric reducing assays were employed to quantify antioxidant properties. Whereas, the disc diffusion assays were used to study antibacterial activity. The results reported the highest phenolic content for ethanolic extract (20.25 ± 0.03 mg gallic acid equivalents per gram of extract). On the other hand, the value of phenolic content was slightly decreased 19.1 ± 0.81 mg gallic acid equivalents per gram of extract for the hot water extract. It was also found that both the extracts were potentially capable of balancing reactive oxygen species. Disc diffusion assay results indicated that the extract of red alga K. alvarezi were more efficient against B. cereus. Among the fatty acids determined levoglucosenone and 4-Pyridinemethanol were present in high percentages in hot water extract whereas Hexamethyl- cyclotrisiloxane followed by 1, 2, 5- Thiadiazole-3-carboxamide, 4-[(2-chloroethyl) amino]-N-(2-hydroxyethyl) were present in ethanolic extract of K. alvarezi. The present study concluded that, hot water extracts of K. alvarezii can be used for large scale production of bioactive compounds utilizing an easily available potential seaweed. Future research of red seaweed will be highly important for pharmaceutical and medicinal field as well as a homogenizer in milk products, toothpaste and jellies in other industrial applications.
Environmental Science
M. Samimi; M. Shahriari Moghadam
Abstract
phenol and phenolic compounds are among the most recognized environmental pollutants which exist in industrial wastewater and enter the biological cycles due to the solubility in water. Bioremediation is one of the cost-effective and Eco-friendly methods for phenol removal. In this study, the most effective ...
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phenol and phenolic compounds are among the most recognized environmental pollutants which exist in industrial wastewater and enter the biological cycles due to the solubility in water. Bioremediation is one of the cost-effective and Eco-friendly methods for phenol removal. In this study, the most effective phenol-degrading bacterial strain was isolated and identified from the shores of the Oman Sea by 16S rDNA. The optimal conditions of various factors, such as pH, temperature, carbon to nitrogen ratio and salinity for the phenol biodegradation, were determined using the experimental design based on Taguchi method with L9 array (34). Ability of the isolated strain (Halomonas elongata strain O-CH1) in degradation of different phenol concentrations was analyzed. The optimum operating conditions for phenol removal were determined in pH value of 8, temperature of 35 ˚C, carbon to nitrogen ratio of 100:30 (g/L) and salinity of 35 (g/L). In these conditions, 97% of the phenol was removed from the mediums. According to the optimization results, salinity and pH were the most influential factors in the biodegradation of phenol. The O-CH1 was able to grow and degrade phenol at concentrations of 250 mg/L to 1500 mg/L. Considering the high potential of this strain for phenol degradation, determining the optimal conditions for the biodegradation and its efficacy at high concentrations of phenol, the findings in this study can be used in the biological treatment of phenolic wastewater.
Environmental Science
A. Mostafa; M. Khalafallah; S. AboSedera; H. Fathy; A. Higazy
Abstract
Chamomile is one of the most wide spread medicinal plant cultivated in Egypt. This work aimed at enhancement of blossoms and oil production of chamomile plants via biofertilization with PGPRs under organic farming system. In this study, 6 bacterial strains were applied using two different inoculation ...
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Chamomile is one of the most wide spread medicinal plant cultivated in Egypt. This work aimed at enhancement of blossoms and oil production of chamomile plants via biofertilization with PGPRs under organic farming system. In this study, 6 bacterial strains were applied using two different inoculation techniques. The first application method was throughout soaking the roots of seedlings in the bacterial suspension before transplanting. The second technique was by adding the bacterial inocula to soil 2 weeks after transplantation. The results showed that root dipping method displayed high impact on the yield of chamomile blossoms and essential oil percentage. Furthermore, the soil application of the bacterial inocula didn’t show any significant impact in this respect. Where Paenibacillus polymyxa, Bacillus subtilis, Serratia plymuthica and Streptomyces subrutilus increased the dry weight of chamomile blossoms compared to the control, essential oil content increased significantly in case of Serratia plymuthica, Stenotrophomonas rhizophyla and Bacillus subtilis. The current results also indicated that bacterial strains produced the highest indole-3-acetic acid and gibberellic acid resulted in the highest yield of both flowers and essential oil.
Environmental Science
A.S. Deshpande; R. Kumari; A. Prem Rajan
Abstract
A multitude of microbes are involved in the solubilisation of minerals and metals as this approach offers numerous advantages over traditional methods. This strategy is preferred as it is eco-friendly and economical, thus overcoming the drawbacks of the traditional approach of pyrometallurgy. Many different ...
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A multitude of microbes are involved in the solubilisation of minerals and metals as this approach offers numerous advantages over traditional methods. This strategy is preferred as it is eco-friendly and economical, thus overcoming the drawbacks of the traditional approach of pyrometallurgy. Many different types of bacteria are employed in the process of Bioleaching, which are collectively grouped under chemolithotrophs, as they derive their energy from inorganic compounds. Bioleaching is the mobilization of metal cations from insoluble ores by microorganisms. All chemolithotropic bacteria are extremophiles since they have the ability to survive in extreme conditions. They carry out the process of Bioleaching through three mechanisms: Indirect, contact/ direct and cooperative bioleaching. This review gives a sneak peek into the different strains of chemolithotrophs which are used in bioleaching, and some recent work in the field. It also gives an insight into the general process and mechanism of Bioleaching, the study of which will pave way for developing better and efficient industrial bioleaching operations.
Environmental Science
M. Noroozi; M.A. Amoozegar; A.A. Pourbabaei; N.S. Naghavi; Z. Nourmohammadi
Abstract
The current study was aimed at isolating and identifying the halophilic and halotolerant bacteria which can produce mercuric reductase in Gavkhuni wetland in Iran. Moreover, tracking and sequencing merA gene and kinetic properties of mercuric reductase in the selected strain were performed in this study. ...
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The current study was aimed at isolating and identifying the halophilic and halotolerant bacteria which can produce mercuric reductase in Gavkhuni wetland in Iran. Moreover, tracking and sequencing merA gene and kinetic properties of mercuric reductase in the selected strain were performed in this study. Soil samples were taken from Gavkhuni wetland and cultured in nutrient agar medium with 5% NaCl. To examine the tolerance of purified colonies to mercury, agar dilution method was administered. Similarly, the phylogenetic analysis based on 16SrRNA gene sequencing was conducted. To investigate enzyme activity of kinetic parameters, a spectrophotometer was used to measure the NADPH oxidation decrease at 340 n.m. The results showed that among the 21 halophilic and halotolerant strains isolated from Gavkhuni wetland, 4 were resistant to mercuric chloride. A strain designated MN8 was selected for further studies because it showed the highest resistance to mercury. According to phylogenetic sequencing of 16S rRNA gene and phenotypic characteristics, the strain was categorized in the Bacillus genus and nearly related to Bacillus firmus. This strain had merA gene. The mercuric reductase showed Vmax and Km values of 0.106 U/mg and 24.051 µM, respectively. Evaluation of different concentrations of NaCl at 37°C and pH=7.5 in mercuric reductase enzyme activity indicated that the enzyme shows 50% activity in concentration of 1.5 M. Optimum pH and temperature of enzyme activity were 7.5 and 35 °C, respectively. The results suggested that MN8 strain could be a proper candidate for bioremediation of mercury-contaminated environments such as industrial wastewaters.
Environmental Science
O. Calderon; H. Porter-Morgan; J. Jacob; W. Elkins
Abstract
Newtown Creek is an industrial waterway and former tidal wetland in New York City. It is one of the most polluted water bodies in the United States and was designated as a superfund site in 2010. For over a century, organic compounds, heavy metals, and other forms of industrial pollution have disrupted ...
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Newtown Creek is an industrial waterway and former tidal wetland in New York City. It is one of the most polluted water bodies in the United States and was designated as a superfund site in 2010. For over a century, organic compounds, heavy metals, and other forms of industrial pollution have disrupted the creek’s environment. The creek is also impacted by discharges from twenty combined sewer overflow pipes, which may deposit raw sewage or partially treated wastewater directly into the creek during heavy or sustained rain events. Combined sewer overflow events and associated nutrient over-enrichment at the creek drive eutrophication and subsequent hypoxia. At the current study, three sites were sampled one week apart during a dry period and a wet period, where indication of a combined sewage overflow event could be detected. 16s rRNA high-throughput sequencing from these three sites collectively yielded over 1000 species of bacteria belonging to twenty-two classes. Based on these data, it is hypothesized that differences identified in the microbiome on wet versus dry days are as a result of combined sewage overflow, street runoff, and additional fluctuations in the creek’s environment associated with rain. It was found that after a combined sewer overflows event, the levels of Gamma Proteobacteria increased while the levels of Actinobacteria decreased. However, levels of bacteria stayed relatively unchanged at a site further away from combined sewer overflows discharge. Species found in Newtown Creek include pelagic, marine, human and animal pathogens, hydrocarbonoclastic, and other environmental microbes.
Environmental Science
M. Ghiasian; A. Akhavan Sepahy; M.A. Amoozegar; S. Saadatmand; M. Shavandi
Abstract
Mud volcanoes are taken into consideration by geologists and oil industry experts have given their association with oil and gas reserves and methane greenhouse gas production in hydrosphere and atmosphere. Gomishan mud volcano phenomenon in the southeastern edge of the Caspian Sea, given its oil and ...
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Mud volcanoes are taken into consideration by geologists and oil industry experts have given their association with oil and gas reserves and methane greenhouse gas production in hydrosphere and atmosphere. Gomishan mud volcano phenomenon in the southeastern edge of the Caspian Sea, given its oil and gas resources, has been studied by some geologists in terms of geology and tectonics but not in terms of microbiology. Accordingly, it seems necessary to study this phenomenon from the perspective of microbiology in order to identify prokaryotes living in this area. Prokaryotes diversity in Mud volcano has been studied by cultivation techniques, fluorescence in situ hybridization, and denaturing gradient gel electrophoresis of PCR-amplified fragments of 16S rRNA genes. Total cell abundance in the mud volcano from 1×101-6×101per milliliter was determined by 4', 6-diamidino-2-phenylindole direct count. The detectable proportion of Archaea to Bacteria in the community by FISH was one to five. High viable counts (1 – 3 × 106) were obtained in culture media. A total of 122 isolates were obtained, 46 colonies were selected based on primarily morphological and physiological traits, and their 16S rRNA sequences were determined. The isolated genera included Halomonas (20%), Arthrobacter (5%), Kocuria (5%), Thalassobacillus (5%), Marinobacter (20%), Paracoccus (5%), Roseovarius (5%), Jeotgalicoccus (5%), Bacillus (15%), and Staphylococcus (15%). Regarding DGGE analysis, selected bands were obtained from the gels, reamplified and sequenced. Overall, 75% of the bacterial sequences were related to Rahnella and 25% related to Serratia.
Environmental Science
Q. Xie; S. Bai; Y. Li; L. Liu; S. Wang; J. Xi
Abstract
This study investigated the microbial community in a full scale anaerobic baffled reactor and sequencing batch reactor system for oil-produced water treatment in summer and winter. The community structures of fungi and bacteria were analyzed through polymerase chain reaction–denaturing gradient ...
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This study investigated the microbial community in a full scale anaerobic baffled reactor and sequencing batch reactor system for oil-produced water treatment in summer and winter. The community structures of fungi and bacteria were analyzed through polymerase chain reaction–denaturing gradient gel electrophoresis and Illumina high-throughput sequencing, respectively. Chemical oxygen demand effluent concentration achieved lower than 50 mg/L level after the system in both summer and winter, however, chemical oxygen demand removal rates after anaerobic baffled reactor treatment system were significant higher in summer than that in winter, which conformed to the microbial community diversity. Saccharomycotina, Fusarium, and Aspergillus were detected in both anaerobic baffled reactor and sequencing batch reactor during summer and winter. The fungal communities in anaerobic baffled reactor and sequencing batch reactor were shaped by seasons and treatment units, while there was no correlation between abundance of fungi and chemical oxygen demand removal rates. Compared to summer, the total amount of the dominant hydrocarbon degrading bacteria decreased by 10.2% in anaerobic baffled reactor, resulting in only around 23% of chemical oxygen demand was removed in winter. Although microbial community significantly varied in the three parallel sulfide reducing bacteria, the performance of these bioreactors had no significant difference between summer and winter.