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1.
BackgroundAcidithiobacillus ferrooxidans is a facultative anaerobe that depends on ferrous ion oxidation as well as reduced sulfur oxidation to obtain energy and is widely applied in metallurgy, environmental protection, and soil remediation. With the accumulation of experimental data, metabolic mechanisms, kinetic models, and several databases have been established. However, scattered data are not conducive to understanding A. ferrooxidans that necessitates updated information informed by systems biology.ResultsHere, we constructed a knowledgebase of iron metabolism of A. ferrooxidans (KIMAf) system by integrating public databases and reviewing the literature, including the database of bioleaching substrates (DBS), the database of bioleaching metallic ion-related proteins (MIRP), the A. ferrooxidans bioinformation database (Af-info), and the database for dynamics model of bioleaching (DDMB). The DBS and MIRP incorporate common bioleaching substrates and metal ion-related proteins. Af-info and DDMB integrate nucleotide, gene, protein, and kinetic model information. Statistical analysis was performed to elucidate the distribution of isolated A. ferrooxidans strains, evolutionary and metabolic advances, and the development of bioleaching models.ConclusionsThis comprehensive system provides researchers with a platform of available iron metabolism-related resources of A. ferrooxidans and facilitates its application.How to citeZhou Z, Ma W, Liu Y, et al. Potential application of a knowledgebase of iron metabolism of Acidithiobacillus ferrooxidans as an alternative platform. Electron J Biotechnol 2021;51; https://doi.org/10.1016/j.ejbt.2021.04.003  相似文献   

2.
BackgroundTraditional methods of obtaining arsenic have disadvantages such as high cost and high energy consumption. Realgar is one of the most abundant arsenic sulphide minerals and usually treated as waste in industry. The aim of the present study was to screen an arsenic tolerant bacterium used for bioleaching arsenic from realgar.ResultsAn acidophilic iron-oxidizing bacterium BYQ-12 was isolated from Wudalianchi volcanic lake in northeast China. BYQ-12 was a motile, rod-shaped gram-negative bacterium with an optimum growth at 30°C and pH 2.5. 16S rDNA phylogeny showed that BYQ-12 was a new strain of Acidithiobacillus ferrooxidans. The inhibitory concentrations (ICs) of arsenite and arsenate were 32 and 64 mM, respectively. A significant second-order model was established using a Box–Behnken design of response surface methodology (BBD-RSM) and it estimated that a maximum arsenic bioleaching rate (73.97%) could be obtained when the pulp concentration, pH and initial ferrous ion concentration were set at optimized values of 0.95% w/v, 1.74 and 3.68 g/L, respectively. SEM, EDS and XRD analyses also revealed that there was direct bioleaching besides indirect electrochemical leaching in the arsenic bioleaching system.ConclusionFrom this work we were successful in isolating an acidophilic, arsenic tolerant ferrous iron-oxidizing bacterium. The BBD-RSM analysis showed that maximum arsenic bioleaching rate obtained under optimum conditions, and the most effective factor for arsenic leaching was initial ferrous ion concentration. These revealed that BYQ-12 could be used for bioleaching of arsenic from arsenical minerals.  相似文献   

3.
BackgroundRemoval of dyes from wastewater by microorganisms through adsorption, degradation, or accumulation has been investigated. Biological methods used for dye treatment are generally always effective and environmentally friendly. In this study, biosorption of the Fast Black K salt azo dye by the bacterium Rhodopseudomonas palustris 51ATA was studied spectrophotometrically, at various pH (2–10), temperatures (25°C, 35°C, and 45°C) and dye concentrations (25–400 mg L-1).ResultsThe bacterial strain showed extremely good dye-removing potential at various dye concentrations. IR studies at different temperatures showed that the dye was adsorbed on the bacterial surface at lower temperatures. Characteristics of the adsorption process were investigated by Scatchard analysis at 25°C and 35°C. Scatchard analysis of the equilibrium binding data for the dye on this bacterium gave rise to linear plots, indicating that the Langmuir model could be applied. The regression coefficients obtained for the dye from the Freundlich and Langmuir models were significant and divergence from the Scatchard plot was observed.ConclusionThe adsorption behavior of the dye on this bacterium was expressed by the Langmuir, Freundlich, and Temkin isotherms. The adsorption data with respect to various temperatures provided an excellent fit to the Freundlich isotherm. However, when the Langmuir and Temkin isotherm models were applied to these data, a good fit was only obtained for the dye at lower temperatures, thus indicating that the biosorption ability of R. palustris 51ATA is dependent on temperature, pH, and dye concentration.How to cite: Öztürk A, Bayol E, Abdullah MI. Characterization of the biosorption of fast black azo dye K salt by the bacterium Rhodopseudomonas palustris 51ATA strain. Electron J Biotechnol 2020;46. https://doi.org/10.1016/j.ejbt.2020.05.002.  相似文献   

4.
BackgroundChia seeds are gaining increasing interest among food producers and consumers because of their prohealth properties.ResultsThe aim of this work was to evaluate the potential of chia seeds to act as acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitors. The highest inhibitory activity against AChE and BChE was observed for colored seed ethanol extracts. A positive correlation was found between the presence of quercetin and isoquercetin as well as protocatechuic, hydroxybenzoic, and coumaric acids and the activity of extracts as AChE and BChE inhibitors. It has also been shown that grain fragmentation affects the increase in the activity of seeds against cholinesterases (ChE). Furthermore, seeds have been shown to be a source of substances that inhibit microbial growth.ConclusionsIt was found that the chia seed extracts are rich in polyphenols and inhibit the activity of ChEs; therefore, their use can be considered in further research in the field of treatment and prevention of neurodegenerative diseases.How to cite: Kobus-Cisowska J, Szymanowska D, Maciejewska P, et al. In vitro screening for acetylcholinesterase and butyrylcholinoesterase inhibition and antimicrobial activity of chia seeds (Salvia hispanica). Electron J Biotechnol 2019;37. https://doi.org/10.1016/j.ejbt.2018.10.002  相似文献   

5.
Azotobacter vinelandii is a gram-negative soil bacterium that produces two biopolymers of biotechnological interest, alginate and poly(3-hydroxybutyrate), and it has been widely studied because of its capability to fix nitrogen even in the presence of oxygen. This bacterium is characterized by its high respiration rates, which are almost 10-fold higher than those of Escherichia coli and are a disadvantage for fermentation processes. On the other hand, several works have demonstrated that adequate control of the oxygen supply in A. vinelandii cultivations determines the yields and physicochemical characteristics of alginate and poly(3-hydroxybutyrate).Here, we summarize a review of the characteristics of A. vinelandii related to its respiration systems, as well as some of the most important findings on the oxygen consumption rates as a function of the cultivation parameters and biopolymer production.How to cite: Castillo T, García A, Padilla-Córdova C, et al. Respiration in Azotobacter vinelandii and its relationship with the synthesis of biopolymers. Electron J Biotechnol 2020;48. https://doi.org/10.1016/j.ejbt.2020.08.001  相似文献   

6.
BackgroundFermentation strategies for bioethanol production that use flocculating Saccharomyces cerevisiae yeast need to account for the mechanism by which inhibitory compounds, generated in the hydrolysis of lignocellulosic materials, are tolerated and detoxified by a yeast floc.ResultsDiffusion coefficients and first-order kinetic bioconversion rate coefficients were measured for three fermentation inhibitory compounds (furfural, hydroxymethylfurfural, and vanillin) in self-aggregated flocs of S. cerevisiae NRRL Y-265. Thièle-type moduli and internal effectiveness factors were obtained by simulating a simple steady-state spherical floc model.ConclusionsThe obtained values for the Thiéle moduli and internal effectiveness factors showed that the bioconversion rate of the inhibitory compounds is the dominant phenomenon over mass transfer inside the flocs.How to cite: Landaeta R, Acevedo F, Aroca G. Effective diffusion coefficients and bioconversion rates of inhibitory compounds in flocs of Saccharomyces cerevisiae. Electron J Biotechnol 2019;42. https://doi.org/10.1016/j.rjbt.2019.08.001  相似文献   

7.
BackgroundPyruvic acid (PA), a vital α-oxocarboxylic acid, plays an important role in energy and carbon metabolism. The oleaginous yeast Yarrowia lipolytica (Y. lipolytica) has considerable potential for the production of PA. An increased NaCl concentration reportedly increases the biomass and PA yield of Y. lipolytica.ResultsTo increase the yield of PA, the NaCl-tolerant Y. lipolytica A4 mutant was produced using the atmospheric and room temperature plasma method of mutation. The A4 mutant showed growth on medium containing 160 g/L NaCl. The PA yield of the A4 mutant reached 97.2 g/L at 120 h (0.795 g/g glycerol) in a 20-L fermenter with glycerol as the sole carbon source, which was 28.9% higher than that of the parental strain.ConclusionThe PA yield from Y. lipolytica can be improved by increasing its NaCl tolerance.How to cite: Yuan W, Lin X, Zhong S, et al. Enhanced pyruvic acid yield in an osmotic stress-resistant mutant of Yarrowia lipolytica. Electron J Biotechnol 2020;44. https://doi.org/10.1016/j.ejbt.2020.01.002.  相似文献   

8.
BackgroundThe potential waste canola oil-degrading ability of the cold-adapted Antarctic bacterial strain Rhodococcus sp. AQ5-07 was evaluated. Globally, increasing waste from food industries generates serious anthropogenic environmental risks that can threaten terrestrial and aquatic organisms and communities. The removal of oils such as canola oil from the environment and wastewater using biological approaches is desirable as the thermal process of oil degradation is expensive and ineffective.ResultsRhodococcus sp. AQ5-07 was found to have high canola oil-degrading ability. Physico-cultural conditions influencing its activity were studied using one-factor-at-a-time (OFAT) and statistical optimisation approaches. Considerable degradation (78.60%) of 3% oil was achieved by this bacterium when incubated with 1.0 g/L ammonium sulphate, 0.3 g/L yeast extract, pH 7.5 and 10% inoculum at 10°C over a 72-h incubation period. Optimisation of the medium conditions using response surface methodology (RSM) resulted in a 9.01% increase in oil degradation (87.61%) when supplemented with 3.5% canola oil, 1.05 g/L ammonium sulphate, 0.28g/L yeast extract, pH 7.5 and 10% inoculum at 12.5°C over the same incubation period. The bacterium was able to tolerate an oil concentration of up to 4.0%, after which decreased bacterial growth and oil degradation were observed.ConclusionsThese features make this strain worthy of examination for practical bioremediation of lipid-rich contaminated sites. This is the first report of any waste catering oil degradation by bacteria originating from Antarctica.How to cite: Ibrahim S, Zahri KNM, Convey P, et al. Optimisation of biodegradation conditions for waste canola oil by cold-adapted Rhodococcus sp. AQ5-07 from Antarctica. Electron J Biotechnol 2020;48. https://doi.org/10.1016/j.ejbt.2020.07.005  相似文献   

9.
Backgroundγ-Aminobutyric acid (GABA) bypasses the TCA cycle via GABA shunt, suggesting a relationship with respiration. However, little is known about its role in seed germination under salt conditions.ResultsIn this study, exogenous GABA was shown to have almost no influence on mungbean seed germination, except 0.1 mM at 10 h, while it completely alleviated the inhibition of germination by salt treatment. Seed respiration was significantly inhibited by 0.1 and 0.5 mM GABA, but was evidently enhanced under salt treatment, whereas both were promoted by 1 mM GABA alone or with salt treatment. Mitochondrial respiration also showed a similar trend at 0.1 mM GABA. Moreover, proteomic analysis further showed that 43 annotated proteins were affected by exogenous GABA, even 0.1 mM under salt treatment, including complexes of the mitochondrial respiratory chain.ConclusionsOur study provides new evidence that GABA may act as a signal molecule in regulating respiration of mungbean seed germination in response to salt stress.How to citeJi J, Shi S, Chen W, et al. Effects of exogenous γ-Aminobutyric acid on the regulation of respiration and protein expression in germinating seeds of mungbean (Vigna radiata) under salt conditions. Electron J Biotechnol 2020;47. https://doi.org/10.1016/j.ejbt.2020.05.005  相似文献   

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12.
BackgroundBioremoval of phenolic compounds using fungi and bacteria has been studied extensively; nevertheless, trinitrophenol bioremediation using modified Oscillatoria cyanobacteria has been barely studied in the literature.ResultsAmong the effective parameters of bioremediation, algal concentration (3.18 g·L−1), trinitrophenol concentration (1301 mg·L−1), and reaction time (3.75 d) were screened by statistical analysis. Oscillatoria cyanobacteria were modified by starch/nZVI and starch/graphene oxide in a bubble column bioreactor, and their bioremoval efficiency was investigated. Modifiers, namely, starch/zero-valent iron and starch/GO, increased trinitrophenol bioremoval efficiency by more than 10% and 12%, respectively, as compared to the use of Oscillatoria cyanobacteria alone.ConclusionsIt was found that starch/nano zero-valent iron and starch/GO could be applied to improve the removal rate of phenolic compounds from the aqueous solution.How to cite: Bavandi R, Emtyazjoo M, Saravi HN, et al. Study of nano-structure zero-valent iron and graphene-oxid capability onbioremoval of trinitrophenol from wastewater in a bubble column bioreactor. Electron J Biotechnol 2019;39. https://doi.org/10.1016/j.ejbt.2019.02.003.  相似文献   

13.
BackgroundRosemary (Rosmarinus officinalis) contains active substances that have desirable properties for industrial and herbal medicine applications, e.g., essential oils (1.5–2.5%), tannins, flavonoids, triterpenes, saponins, resins, phytosterols, rosmarinic acid and many others. The aim of this study was to determine the influence of rosemary extract and 20% rapeseed oil substitution for animal fat on storage changes and inhibition of cholinesterases in liver pâté.ResultsPreliminary research showed that rosemary extract exhibited antioxidative activity in the system of accelerated Rancimat and Oxidograph tests. Then, rosemary extract was used as an ingredient in liver pâté. During the experiment, meat samples were refrigerated and tested on days 1, 5, 8, 12 and 15 after production. The study proved that the substitution of 20% of animal fat with rapeseed oil decreased the content of saturated acids and increased the content of monoenic fatty acids by approximately 5% and polyene fatty acids by 40%.ConclusionsIn addition to antioxidative activity, the rosemary extract affected the health-promoting value of the samples, which inhibited cholinesterase activity during the entire storage period. The extract inhibited AChE more than BChE.How to cite: Bilska A, Kobus-Cisowska J, Kmiecik D, et al. Cholinesterase inhibitory activity, antioxidative potential and microbial stability of innovative liver pâté fortified with rosemary extract (Rosmarinus officinalis). Electron J Biotechnol 2019;40. https://doi.org/10.1016/j.ejbt.2019.03.007  相似文献   

14.
BackgroundThe harmful effects of type 2 diabetes mellitus and its complications have become a major global public health problem. In this study, the effects of Momordica charantia saponins (MCS) on lipid metabolism, oxidative stress, and insulin signaling pathway in type 2 diabetic rats were investigated.ResultsMCS could attenuate the tendency of weight loss of the model rats. It could also improve glucose tolerance; reduce fasting blood glucose, nonesterified fatty acid, triglyceride, and total cholesterol; and increase the insulin content and insulin sensitivity index of the rats. The activity of superoxide dismutase and catalase increased, and the content of malondialdehyde decreased in the liver and pancreas tissues of rats in MCS-treated groups significantly. In addition, the expression of p-IRS-1 (Y612) and p-Akt (S473) increased, and the expression of p-IRS-1 (S307) decreased in the liver tissues and pancreas tissues of rats in MCS-treated groups significantly.ConclusionMCS has an antidiabetic effect, which may be related to its improving the lipid metabolism disorder, reducing oxidative stress level, and regulating the insulin signaling pathway.How to cite: Jiang S, Xu L, Xu X, et al. Anti-diabetic effect of Momordica charantia saponins in rats induced by high-fat diet combined with STZ. Electron J Biotechnol 2020;43. https://doi.org/10.1016/j.ejbt.2019.12.001.  相似文献   

15.
BackgroundFor more than a decade, water-soluble, eco-friendly, biocompatible, and low-toxicity fluorescent nanomaterials have received considerable attention for their numerous in vivo and in vitro applications in biomedical imaging, disease diagnostics, and environmental monitoring. Owing to their tunable photoluminescence properties, carbon-based luminescent nanomaterials have shown great potential in bioimaging, photocatalysis, and biosensing among other applications.ResultsMarine environments provide excellent resources for the fabrication of these nanomaterials, because many marine organisms contain interesting trigger organic compounds that can be used as precursors. Herein, we synthesize multi-color emissive carbon dots (CDs) with an intrinsic photoluminescence quantum yield of 20.46%. These nanostructures were achieved through the one-step hydrothermal treatment of marine polysaccharide chondroitin sulfate, obtained from shark cartilage, in aqueous solution.ConclusionsWe successfully demonstrate the low toxicity of our marine resource-derived CDs in zebrafish, and provide an initial assessment of their possible use as a bioimaging agent. Notably, the newly synthesized CDs localize in the intestines of zebrafish larvae, thereby indicating their biocompatibility and potential use as in vivo dyes.How to cite: Kim KW, Choi TY, Kwon YM, et al. Simple synthesis of photoluminescent carbon dots from a marine polysaccharide found in shark cartilage. Electron J Biotechnol 2020;47. https://doi.org/10.1016/j.ejbt.2020.07.003.  相似文献   

16.
BackgroundThe intestinal bacterial community has an important role in maintaining human health. Dysbiosis is a key inducer of many chronic diseases including obesity and diabetes. Kunming mice are frequently used as a model of human disease and yet little is known about the bacterial microbiome resident to the gastrointestinal tract.ResultsWe undertook metagenomic sequencing of the luminal contents of the stomach, duodenum, jejunum, ileum, cecum, colon, and rectum of Kunming mice. Firmicutes was the dominant bacterial phylum of each intestinal tract and Lactobacillus the dominant genus. However, the bacterial composition differed among the seven intestinal tracts of Kunming mice. Compared with the small intestine, the large intestine bacterial community of Kunming mice is more stable and diverse.ConclusionsTo our knowledge, ours is the first study to systematically describe the gastrointestinal bacterial composition of Kunming mice. Our findings provide a better understanding of the bacterial composition of Kunming mice and serves as a foundation for the study of precision medicine.How to cite: Han X, Shao H, Wang Y, et al. Composition of the bacterial community in the gastrointestinal tract of Kunming mice. Electron J Biotechnol 2020;43. https://doi.org/10.1016/j.ejbt.2019.11.003  相似文献   

17.
BackgroundAgkistrodon acutus, a traditional Chinese medicine, clinically used in the treatment of rheumatism, tumor, and cardiovascular and cerebrovascular diseases. Due to the unique medicinal value and the difficulty of artificial breeding of Agkistrodon acutus, the supply of Agkistrodon acutus on the market exceeds the demand, and a large number of its adulterants are found on the market. In this study, the cytb gene sequences of Agkistrodon acutus and 9 snakes were compared and analyzed, specific primers were designed, and specific PCR methods were established to detect Agkistrodon acutus medicinal samples on the market.ResultsThis method was successfully applied to distinguish the snake from other adulterated species, and tested 18 Agkistrodon acutus samples randomly purchased from six cities. Twelve samples were counterfeit and six were genuine. The standard reference material of Agkistrodon acutus was cloned by molecular cloning and sequencing, and the gene sequence difference with other species was significant. It shows that the region could be used as the fingerprint region of the target species.ConclusionsThe proposed method can be used as a species-specific marker and can be highly distinguished from other adulterated snake species, which is helpful to effectively avoid the problem of false sale of Agkistrodon acutus.How to cite: Yingnuo L, Yanshuang W, Mingcheng Li, et al. Development of a species-specific PCR assay for authentication of Agkistrodon acutus based on mitochondrial cytochrome b gene. Electron J Biotechnol 2021;49. https://doi.org/10.1016/j.ejbt.2020.07.005  相似文献   

18.
BackgroundAmmonium stress is a prime limiting phenomenon that occurs during methane formation from poultry manure. It is caused by elevated ammonium nitrogen concentrations that result from substrate decomposition. The amounts of methane formed depend on the activity of methanogenic microbes.ResultsDuring the research reported in this paper, the response of a mesophilic consortium inhabiting a biogas reactor to rising load of poultry manure was investigated. The taxonomic composition of bacterial population was mostly typical, however syntrophic bacteria were not detected. This absence resulted in limitation of succession of some methanogenic microorganisms, especially obligate hydrogenotrophs. The methanogenic activity of the consortium was totally dependent on the activity of Methanosaeta. Inhibition of methanoganesis was noticed at ammonium nitrogen concentration of 3.68 g/L, total cessation occurred at 5.45 g/L. Significant amounts of acetic acid in the fermentation pulp accompanied the inhibition.ConclusionsThe effectiveness of the consortium was totally dependent on the metabolic activity of the acetoclastic Methanoseata genus and lack of SAOB did not allow hydrogenotrophic methanogens to propagate and lead to cessation of biogas production at an elevated ammonium concentration at which acetoclastic methanogens were inhibited.How to cite: Świątek M, Lewicki A, Szymanowska D, et al. The effect of introduction of chicken manure on the biodiversity and performance of an anaerobic digester. Electron J Biotechnol 2019;37. https://doi.org/10.1016/j.ejbt.2018.11.002.  相似文献   

19.
BackgroundWheat is one of the most important crops cultivated all over the world. New high-yielding cultivars that are more resistant to fungal diseases have been permanently developed. The present study aimed at the possibility of accelerating the process of breeding new cultivars, resistant to eyespot, by using doubled haploids (DH) system supported by marker-assisted selection.ResultsTwo highly resistant breeding lines (KBP 0916 and KBH 4942/05) carrying Pch1 gene were crossed with the elite wheat genotypes. Hybrid plants of early generations were analyzed using endopeptidase EpD1 and two SSR markers linked to the Pch1 locus. Selected homozygous and heterozygous genotypes for the Pch1-linked EpD1b allele were used to produce haploid plants. Molecular analyses were performed on haploids to identify plants possessing Pch1 gene. Chromosome doubling was performed only on haploid plants with Pch1 gene. Finally, 65 DH lines carrying eyespot resistance gene Pch1 and 30 lines without this gene were chosen for the eyespot resistance phenotyping in a field experiment.ConclusionsResults of the experiment confirmed higher resistance to eyespot of the genotypes with Pch1 in comparison to those without this gene. This indicates the efficiency of selection at the haploid level.How to cite: Wiśniewska H, Majka M, Kwiatek M, et al. Production of wheat doubled haploids resistant to eyespot supported by marker-assisted selection. Electron J Biotechnol 2019;37. https://doi.org/10.1016/j.ejbt.2018.10.003  相似文献   

20.
BackgroundAPETALA3 (AP3) has significant roles in petal and stamen development in accordance with the classical ABC model.ResultsThe AP3 homolog, CDM19, from Chrysanthemum morifolium cv. Jinba was cloned and sequenced. Sequence and phylogenetic analyses revealed that CDM19 is of DEF/AP3 lineage possessing the characteristic MIKC-type II structure. Expression analysis showed that CDM19 was transcribed in petals and stamens of ray and disc florets with weak expression in the carpels. Ectopic expression of CDM19 in Arabidopsis wild-type background altered carpel development resulting in multi-carpel siliques. CDM19 could only partially rescue the Arabidopsis ap3–3 mutant.ConclusionsOur results suggest that CDM19 may partially be involved in petal and stamen development in addition to having novel function in carpel development.How to cite: Githeng’u SK, Ding L, Zhao K, et al. Ectopic expression of Chrysanthemum CDM19 in Arabidopsis reveals a novel function in carpel development. Electron J Biotechnol 2020;45. https://doi.org/10.1016/j.ejbt.2020.03.001.  相似文献   

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