Biological Activity Of Microorganisms Research Articles

Soil Health in an Integrated Production System in a Brazilian Semiarid Region

Soil health is directly related to sustainable development goals (SDGs) and can be affected by inadequate management practices. In this work, soil edaphic respiration and changes in microbial biomass promoted by cover crops in an integrated crop–livestock system (ICLS) were evaluated using soil health indicators with the respirometry method. The design was completely randomized in a 3 × 6 factorial arrangement, and multivariate principal components analysis (PCA) was performed according to MANOVA. Edaphic respiration was determined based on the respirometry technique. The results showed that edaphic soil respiration was significant in the nine evaluation periods, demonstrating the importance of grass cover in edaphic respiration arising from the biological activity of microorganisms, which is directly related to the amount of soil organic carbon. The cover crops increased soil organic matter and consequently microbial respiratory activity.

Microbial bioremediation: Effective Strategy for Removal of Pollutants from Contaminated Industrial Water of Textile Mills Plants. An Overview

Bioremediation is a process used to treat contaminated water by altering environmental conditions to stimulate growth of microorganisms and degrade the target pollutants. Microbial bioremediation uses microorganisms to break down contaminants by using them as a food source. These toxic compounds are metabolized by enzymes of microorganisms. The industrial water contaminated by heavy metals and other pollutants are common throughout the world. Many strategies are developed to encourage the degradation of pollutants from such affected sites. Bioremediation as one feasible way to be used. It is a technology that employs living microorganisms such as bacteria and fungi to remove harmful contaminants from the polluted environment. The basis of bioremediation is that microorganisms remove substances from the environment to carry out their growth and metabolism. The microorganisms used in this strategy can be both indigenous and non-indigenous. These microorganisms take part in the degradation, immobilization, and detoxification of various harmful chemical wastes and contaminants. Microorganisms which perform the function of bioremediation are known as bio-remediators or bio-reformers. The treatment of contaminated water by the conventional method is found to be unfeasible due to its high cost and generates secondary pollutants. Therefore, bioremediation is not effective only for the degradation of pollutants but it can also be used to clean unwanted substances in industrial water and raw materials form industrial waste through the biological activities of microorganisms. Microbial growth depends on several environmental factors such as pH, temperature, and nutrients. The practice bio-stimulation that involves the addition of nutrients to the contamination site enhances the growth of microbes that assist in bioremediation. One of the main nutrients is molasses, in Iraq we used a natural material (dates extracts) in bioremediation of industrial water of textile mills plants.

A Very Large-Scale Integration Global Routing Optimization Model for Hybrid Physarum Bionetworks

Interconnection of billion transistors in a single layer of a die with the advent of the nanometer regime imposes a great challenge to handle the increased complexity, particularly in the global routing of the Very Large-Scale Integration (VLSI) physical design phase which involves distinct optimization in the computation of overall interconnect wire-length. In classical graph theory, the VLSI global routing problem can be mapped as a Rectilinear Steiner Minimal Tree (RSMT) Problem, which in itself is an NP-complete problem. The use of metaheuristics in solving this problem plays a major role where Ant Colony Optimization (ACO) and Particle Swarm Optimization (PSO) proved to be efficient algorithms. Both algorithms face certain limitations and inconsistencies in determining maximum optimization. A new optimization algorithm with insight from the biological activity of microorganisms has been proposed in this paper which is based on the behavior of the unicellular organism Physarum Polycephalum aiming at minimizing the wire length of VLSI interconnects. The paper further explores a new hybridization technique employing the use of Physarum BioNetwork and Particle Swarm Optimization together where PSO generate better possible Steiner’s in the initial stage for the final process using Physarum BioNetwork to ensure better convergence. Complexity analysis of the proposed algorithm has been performed and the simulation results achieved greater efficiency when compared with the conventional PSO algorithm and available industry benchmark over-optimizing Global Routing problem in VLSI design.

Fermentation and diet diversity: Biochemical and functional properties of fermented mango (Mangifera Indica L) pulp flour

Processing of plant foods has been in practice over a long period of time for various reasons; ranging from optimization of product quality, such as improvement in flavour, texture, nutrient density, and bioavailability as well as reduction in viscosity, bulkiness, and antinutritional factors/toxins or for improvement of functional properties for use in other food systems. Indigenous food fermentation is one of the oldest ‘food biotechnological processes’ dependent on the biological activity of microorganisms from which the development of fermented foods is achieved in the cultural history of human beings. Mango (Mangifera indica) is a tropical fruit plant that contains high levels of nutrients, fibre, macronutrients, micronutrients, and minerals as well as abundant bioactive compounds such as antioxidants and polyphenols reported to be an alternative to enhance body immunity. This study is to process fermented mango pulp flour and the effects of the period of fermentation time on the chemical composition and selected functional properties of mango pulp flours were examined. The fermentation time ranged from 0-72 h with Flour of the unfermented (0hr) Mango serving as control. Fermentation for 24hr to 72hrs significantly increased (p<0.05) crude protein and total ash in the flours. Ether extract and carbohydrates significantly decreased (p<0.05) in the flours with an increase in fermentation time. Significant (p<0.05) reduction in Bulk density, swelling index, and water absorption capacity occurred in the flour with fermentation. There was a significant (P<0.05) increase in Vitamin C and beta–carotene content of the fermented samples and this was constant as fermentation progressed across all the samples. Therefore, fermented mango flours have a great potential to be developed into healthy foods since antioxidants have the ability to improve immunity and anti-inflammatory response.

Large scale mapping of soil organic carbon concentration with 3D machine learning and satellite observations

Canada has extensive forests and peatlands that play key roles in global carbon cycle. Canadian soils and peatlands are assumed to store approximately 20% of the world’s soil carbon stock. However, the spatial and vertical distributions of the soil organic carbon (SOC) concentration in Canada have not been systematically investigated. SOC concentration, expressed in g C kg−1 soil, affects the chemical and physical properties of the soil, such as water infiltration ability, moisture holding capacity, nutrient availability, and the biological activity of microorganisms. In this study, we tested a three dimensional (3D) machine learning approach and 40 spatial predictors derived from 20 years of optical and microwave satellite observations to estimate the spatial and vertical distributions of SOC concentration in Canada in six depth intervals up to 1 m. A quantile regression forest method was used to build an uncertainty map showing 80% of prediction intervals. Results showed that a random forest model associated with 25 covariates was successful in capturing 83% of spatial and vertical SOC variation over the country. Soil depth was the most important covariate to predict SOC concentration, followed by surface temperature and elevation. The SOC concentration in forested areas was highest in the top layers (0–5 cm), but soils located in peatlands showed higher C concentration in all soil depths. Among the terrestrial ecozones of Canada, Pacific Maritime and the Hudson Plain mostly covered by forest trees and peatlands, respectively, show highest SOC concentration, while the lowest concentration are observed in the Prairies and Mixed Wood Plain ecosystems that are the agricultural areas of the country. This study provides a deeper understanding of the major factors controlling SOC concentration in Canada and shows potential areas with high carbon reserves, which are crucial in view of the ongoing climate change. In addition, the presented methodological framework has great potential to be used in future soil carbon storage inventories using satellite observations. Mapping SOC concentration and associated uncertainties in Canada are fundamental to detect trends of gains or losses in SOC linked to recent and future national or global policy decisions related to soil quality and carbon sequestration.

Foamed Glassy Phosphate Materials for Biosorbents

The paper considers the applications of foamed glassy phosphate materials as carriers of biologically active substances. One of the advantages of phosphate materials is their ability to effectively support the life of microorganisms. This feature of phosphate glassy materials opens up the prospects for the application of microorganism strains - destructors of oil products to their foamed samples, that is, the creation of biosorbents for purification of water and soil from hydrocarbon contamination. The advantages of a biosorbent are explained by the high biological activity of microorganisms on the surface of foamed glassy phosphates and the possibility of active development of microorganisms with the simultaneous destruction of petrochemical contaminants. The use of biosorbent eliminates the problem of its utilization and regeneration, thus it is suitable for repeated use. The formation of porous glassy phosphate materials on the surface by the method of molecular layering of monolayer coatings allows obtaining chemically modified composite materials, which improves their performance characteristics such as strengthening the material structure with a simultaneous increase in the catalytic activity of biochemical processes.

Community Composition and Ex Situ Cultivation of Fungi Associated with UNESCO Heritage Monuments in the Bay of Naples

The Bay of Naples, Italy, is renowned for its archaeological heritage. However, this heritage is threatened by the combination of weathering and the biological activity of microorganisms. Fungi are among the major agents of microbial deterioration of cultural heritage since they can cause cracks and lesions in monuments due to the penetrating force of their hyphae. Such biodeterioration may weaken the stone structures and threaten the longevity of these culturally important monuments. To address this, we collected, identified, and maintained in culture filamentous fungi that colonize the external surface of monuments at five important archaeological sites near Naples, namely Cuma, Ercolano, Nola, Oplonti, and Pompei. We isolated a total of 27 fungal taxa, all of which can be cultivated in the laboratory, and form a part of our reference collection. Many of the described fungal taxa we found belong to groups that are involved in stone biodeterioration and can thus be considered as model organisms for in vitro studies. These results emphasize the importance of identifying and cultivating fungal stock cultures for non-invasive studies on biodeterioration. Our newly developed reference collection represents a useful resource that is available to other researchers to rapidly identify potentially hazardous fungi on other monuments.

Aggregation kinetics of binary systems containing kaolinite and Pseudomonas putida induced by different 1:1 electrolytes: specific ion effects

Background The interactions between colloidal particles in the binary systems or mixture colloids containing clay minerals and bacteria have important influences on formations and stabilities of soil aggregates, transportations of soil water, as well as biological activities of microorganisms. How the interfacial reaction of metal ions affects their interaction therefore becomes an important scientific issue. Methods Dynamic light scattering studies on the aggregation kinetics of mixture colloids containing kaolinite and Pseudomonas putida (P. putida) were conducted in this study. Results Aggregation could be observed between kaolinite and kaolinite, between kaolinite and P. putida when P. putida content was less than 33.3%. Additionally, aggregation rates decreased with increasing P. putida content. The critical coagulation concentrations and activation energies indicated that there were strong specific ion effects on the aggregation of mixture colloids. Most importantly, the activation energy increased sharply with increasing P. putida content, which might result from the lower Hamaker constant of P. putida compared with that of kaolinite. Contributions (1) Strong specific ion effects on mixture colloids aggregation of kaolinite-P. putida were observed; (2) the aggregation behavior of mixture colloids was determined by the average effects of mixture colloids, rather than the specific component. This finding provides an important methodological guide for further studies on the colloidal aggregation behavior of mixture systems with organic and inorganic materials.

Characteristics of the resistance of microorganisms to antimicrobial drugs

The resistance of microorganisms to antimicrobial drugs is an important problem of medicine. The aim – to study forming of the resistance to decamethoxine® (DCM®), decaminum (DC) and properties of microorganisms. In the study, a quantitative assessment of antimicrobial drugs was performed based on the activity index of the drug (AID), which shows the ratio of the working concentration of antiseptic to its minimum active concentration for a specific agent. The first indicator for determining the AID is derived from the instructions for the use of the drug, the relevant directories. Minimum inactivation concentration (MIC) values was determined experimentally in strains of the corresponding species that did not have contact with medicinal products. Microbiological studies on diphtheria rods, Staphylococcus albus and S. aureus, clinical strains of Candida albicans, which possessed typical tinctorial, morphologic, and cultural properties were carried out in this work. The effective concentrations of medicinal antimicrobial drugs decamethoxine®, decaminum, levorinum, nystatin were determined by means of the method of double serial dilutions. Conditions were defined for the formation of resistant forms of microorganisms (nutrient medium, microbial load, concentration of drugs). There was analyzed the resistance of Staphylococci, Corynebacterium diphtheria, Candida albicans drugs and the monitoring of the resistance of microorganisms to decamethoxine®, decaminum, levorinum, nystatin was carried out. According to the results of experimental study on the nutrient medium the slow forming of resistance in Staphylococci, C.diphtheria, C.albicans to DCM and DC were found. These studies showed a lack of cross-resistance of clinical strains of C.albicans to antimycotics DCM® and DC, on the one hand, and levorinum and nystatin on the other. Resistant to DCM of C.albicans were found to be susceptible to decaminum (3,9 μg/ml), levorinum (0,12 μg/ml) and nystatin (1,9 μg/ml). While forming the resistance to antimicrobial drugs changes of morphology with the formation of polymorphic cells have been established in microorganisms. The loss of biological activity of microorganisms due to changes in the activity of microbial cell enzymes during the formation of resistance was determined. The expediency of using DCM®, decaminum, levorinum, nystatin for prevention, treatment, overcoming of resistance in resistant variants of microorganisms to DCM®, decaminum.

Deshidratación de los lodos en lecho de secado y su influencia sobre la actividad biológica de los microorganismos

El objetivo del presente trabajo fue evaluar el efecto de la deshidratación de los lodos en lecho de secado sobre las características fisicoquímicas de estos subproductos y la actividad biológica de los microorganismos. Se determinó que después de cinco meses de secado disminuyó la concentración de carbono orgánico, los metales pesados se mantuvieron por debajo del límite permisible y el nitrógeno y fósforo total se mantuvieron constantes. Se evidenció disminución de los aerobios mesófilos, hongos y amilolíticos de siete, seis y una unidad logarítmica de UFC/g respectivamente. La presencia de microorganismos funcionales celulolíticos y solubilizadores de fosfato fue <10 UFC/g. Por otro lado, el 3 % (n=8040) de las cepas evaluadas, fueron productoras de PHA en por lo menos una de las fuentes de carbono evaluadas (sacarosa o glucosa). Los resultados demuestran que el tratamiento de deshidratación en lecho de secado permitió conservar las características fisicoquímicas de los lodos, no obstante, disminuyó la actividad biológica de los microrganismos aerobios mesófilos, amilolíticos y hongos, celulolíticos, solubilizadores de fosfato.

The changes in soil-biological processes and structure of microbial community of agrochernozems in conditions of different ways of soil cultivation

The impact of soil cultivation methods (tillage with soil overturning at a depth of 20-22 and 14-16 cm, beardless plowing and surface treatment respectively at a depth of 14-16 and 6-8 cm, and also zero or minimal tillage)) on biological activity of various ecology-trophic groups of microorganisms on agronochernozems of the Kamennaya Steppe (Voronezh oblast) using classical inoculation methods on elective media. It is shown that chernozems are highly resistant soils that are resistant to external impacts, preserving high biological activity even at the maximum mechanical treatment. Tillage with soil overturn leads to aeration of the arable horizon and the activity initiation of aerobic microorganisms of the carbon cycle, responsible for the mineralization of both complex and simple organic compounds of the soil. The contribution of microorganisms of the nitrogen cycle (nitrate-reducers and nitrogen fixers) to the overall biological activity of migratory-micellar chernozems of arable land and layland was minimal. The level of mechanical impact on the soil affects the quantitative indices and biological activity of microorganisms in the soil - the stronger the effect, the deeper layers are affected. The processes of entrance for fresh organic matter prevail over the processes of mineralization practically in all variants of the experiment, except for tillage with the soil overturn to a depth of 14-16 cm, as indicated by the values of the mineralization coefficients. The strongest humus-accumulative effect was observed in the variant with zero treatment, which is maximally approximated to such processes, occurred in a layland. Minimal soil cultivation will help to preserve the unique structure of chernozem soil, to increase the flow of fresh organic remains, to preserve the high biological diversity which is specific for natural biocenosises.

Examining the Effects of Typical Reagents for Sulfide Flotation on Bio-Oxidation Activity of Ferrous Iron Oxidizing Microorganisms

Mineral separation by froth flotation is widely used around the world for the beneficiation of sulfide ores. Flotation products (typically concentrate) are subjected to metallurgical processes for metal extractions. Bioleaching as a metallurgical procedure indicated many advantages over other traditional techniques (pyro- and hydro-metallurgy). However, organic flotation reagent residuals on the surface of minerals are effective on biological activities of microorganisms. In this work, to extensively study these effects, typical sulfide flotation collectors (Sodium ethyl-xanthate, Potassium isopropyl-xanthate, Potassium isobutyl-xanthate, Potassium amyl-xanthate, and Dithiophosphate (Aero)), and frothers (pine oil (PO) and methyl isobutyl Carbinol (MIBC)) were used in the presence of various bacteria (Acidithiobacillus ferrooxidans and Leptospirillum ferrooxidans) to investigate their effects on bio-oxidation. The results of this investigation can be used to better understand the mechanisms of bio-activities when reagent residues are on the surface of flotation products and they will feed to the bioleaching process.

A survey of microorganism and its biological effects in the straw covered field

This study compared and determined the quantities, types and biological activities of microorganisms in the soil covered and uncovered with straw. By creating straw mulch on the soil, the number of /nitrogen fixation/ useful bacteria has increased 1.3-2.2 times more than in the uncovered field. Also the cellular depleting bacteria around 0.7 million pieces, and the number of fungal pathogen 0.17 million pieces more than in the uncovered version. The soil biological activity has decreased 0.0037-0.0009 kg. hour/ha at the beginning of planting and at the end of harvesting. It depends on the number of bacteria.Mongolian Journal of Agricultural Sciences Vol.15(2) 2015; 86-90

Investigating phase transformations in hard tissues of the human tooth during the carious process by means of Raman microspectroscopy and luminescence

Investigations of the regions of the nascent enamel carious process confirm assumptions on the formation of weak phosphates during the interaction between enamel apatite and organic acids (products of the biological activity of microorganisms). The described approach for determining regions of hard tooth tissue with an incipient carious process could form the basis for a new approach to caries diagnosis.

Nitrate and ammonium ions contents in field minibioreactors with Antarctic freshwater autotrophs

The content of nitrate and ammonium ions in aquatic environment is an important factor in the development of microorganisms colonies especially in low-nutrient environment. In this study, field experiments using small-volume minibioreactors were performed directly on the James Ross Island in Antarctica in order to describe changes in nitrate and ammonium ions contents in the Antarctic environment The ion concentrations in minibioreactors with local freshwater autotrophs was monitored for increased eutro-phication conditions. The content of nitrogen forms was determined in water samples taken from the minibioreactors regularly. Samples were taken to the laboratory of the Johann Gregor Mendel station where nitrogen content was evaluated using ion-selective electrodes. Furthermore, the freshwater autotrophs was subjected to basic taxonomic study. Closed system of the minibioreactors allowed the monitoring of nitrogen speciation changes which take place in the environment. These changes can be attributed to both the biological activity of microorganisms and external conditions. Increased eutrophication of water did not induce a rapid development of the freshwater autotrophs.

Inhibition of boric acid and sodium borate on the biological activity of microorganisms in an aerobic biofilter

The aim of this work was to study the inhibition effect of boric acid and sodium borate on the treatment of boron containing synthetic wastewater by a down flow aerobic fixed bed biofilm reactor at various chemical oxygen demand (COD)/boron ratios (0.47–20.54). The inhibitory effect of boron on activated sludge was evaluated on the basis of COD removal during the experimental period. The biofilter (effective volume=2.5 L) was filled with a ring of plastic material inoculated with acclimated activated sludge. The synthetic wastewater composed of glucose, urea, KH2PO4, MgSO4, Fe2SO4, ZnSO4·7H2O, KCl, CaCl2, and di-sodium tetraborate decahydrate or boric acid (B=100–2000 mg L−1). The biological treatment of boron containing wastewater resulted in a low treatment removal rate due to the reduced microbial activity as a result of toxic effects of high boron concentrations. The decrease in the COD removal rate by the presence of either boric acid or sodium borate was practically indistinguishable. It was observed from the experiments that about 90–95% of COD removal was possible at high COD/boron ratios.

The Influence of the Organic Matter of Sewage Sediments on Biological Activity of Microorganisms which Carry Out the Transformations of Carbon and Nitrogen Compounds

Soil microorganisms play an important role in the organic matter transformation process. The soil microorganisms also are in symbiotic relationship with plants. At the same time, soil microorganisms are sensitive to both anthropogenic and natural habitat changes. Particular characteristics of organic matter (the C:N relation, pH, the content the content of assimilated nutrients, the xenobiotics etc.) modify the biotic conditions of the soils. This particularly concerns the microorganisms which carry out the changes in the mineral and organic nitrogen compounds and the transformation of the external organic matter. The first aim of this work was to assess the influence of the sewage sediments and the manure on the phytosanitary potential of the soil environment. The second aim of this article was to estimate the number and activity of microorganisms which carry out the transformation of carbon and nitrogen compounds. This work showed the stimulating effect of the external organic matter both on the number and on the activity of most of the physiological groups. The manure mainly stimulated ammonificators, amylolitic microorganisms and Azotobacter sp. The sewage sediments mainly stimulated ammonificators, nitrifiers of I phase and cellulolytic microorganisms. The statistically significant impact of the physio-chemical soil habitat on the biological activity of the analyzed groups of microbes was also noted.

Self-heating in a bioreactor: Coupling of heat and mass transfer with turbulent convection

A tridimensional mathematical model that considers the turbulent flow inside a bioreactor of municipal waste material (MWM) is studied. The MWM is self-heating by the biological activity of micro-organisms. The model includes the unsteady solution of the turbulent flow field inside the reactor, the energy transport in the flow and the ensuing heat and mass transfer by convection over the MWM load. The MWM is treated as a porous medium and the oxygen depletion and heat generation produced by aerobic bacteria are also included. Turbulence treatment is done with the κ–ε model. The numerical simulation shows good agreement with experimental measurements available. The results also shed light over some design criteria that can be explored in order to increase the efficiency of the process.

Controlling pH in shake flasks using polymer-based controlled-release discs with pre-determined release kinetics

BackgroundThere are significant differences in the culture conditions between small-scale screenings and large-scale fermentation processes. Production processes are usually conducted in fed-batch cultivation mode with active pH-monitoring and control. In contrast, screening experiments in shake flasks are usually conducted in batch mode without active pH-control, but with high buffer concentrations to prevent excessive pH-drifts. These differences make it difficult to compare results from screening experiments and laboratory and technical scale cultivations and, thus, complicate rational process development. In particular, the pH-value plays an important role in fermentation processes due to the narrow physiological or optimal pH-range of microorganisms. To reduce the differences between the scales and to establish a pH-control in shake flasks, a newly developed easy to use polymer-based controlled-release system is presented in this paper. This system consists of bio-compatible silicone discs embedding the alkaline reagent Na2CO3. Since the sodium carbonate is gradually released from the discs in pre-determined kinetics, it will ultimately compensate the decrease in pH caused by the biological activity of microorganisms.ResultsThe controlled-release discs presented here were successfully used to cultivate E. coli K12 and E. coli BL21 pRSET eYFP-IL6 in mineral media with glucose and glycerol as carbon (C) sources, respectively. With glucose as the C-source it was possible to reduce the required buffer concentration in shake flask cultures by 50%. Moreover, with glycerol as the C-source, no buffer was needed at all.ConclusionsThese novel polymer-based controlled-release discs allowed buffer concentrations in shake flask media to be substantially reduced or omitted, while the pH remains in the physiological range of the microorganisms during the whole cultivation time. Therefore, the controlled-release discs allow a better control of the pH, than merely using high buffer concentrations. The conditions applied here, i.e. with significantly reduced buffer concentrations, enhance the comparability of the culture conditions used in screening experiments and large-scale fermentation processes.

Key Factors Regarding Decolorization of Synthetic Anthraquinone and Azo Dyes

The factors affecting decolorization of anthraquinone dye represented by Reactive Blue 4 (RB4) and azo dye represented by Methyl Orange (MO) were studied in batch experiments under mesophilic (35 degrees C) and thermophilic (55 degrees C) anaerobic conditions. The results indicated differences in decolorization properties of the dyes with different chromophore structures. In abiotic conditions, MO could be decolorized by a physicochemical reaction when it was sterilized at 121 degrees C together with sludge cells or glucose. RB4 only showed absorption onto the cell mass. The presence of a redox mediator accelerated the decolorizing reaction when supplied together with glucose in the presence of sterilized sludge cells. In biotic conditions, the results indicated that the biological activity of microorganisms was an important factor in decolorization. The main factor involved in decolorization was the conversion of cosubstrate as electron donor, which reacted with dye as an electron acceptor in electron transfer. Redox mediators, anthraquinone-2-sulfonic acid, and anthraquinone could accelerate decolorization even if a small amount (0.2 mM) was applied. On the other hand, a high concentration of redox mediator (1.0 mM) had an inhibitory effect on decolorization especially under thermophilic conditions. In addition, the decolorization of dye was accelerated by increasing treatment temperature, as shown in biotic treatments. Based on these results, increasing the treatment temperature could be used to improve the decolorizing process of textile dye wastewater treatment, especially for recalcitrant dyes such as anthraquinone.