Abstract: Environment free of pollutants should be the concern of every individual but with industrialization and urbanization it is difficult to achieve. In view of achieving a pollution limited environment at low cost, a study was conducted on the use of bioremediation technology to remediate hydrocarbons and three heavy metals namely; copper (Cu), zinc (Zn) and iron (Fe) from a typical petroleum refinery wastewater in a closed system. Physicochemical and microbiological characteristics on the wastewater sample revealed that it was polluted with the aforementioned pollutants. Isolation and identification of microorganisms present in the wastewater sample revealed the presence of Bacillus subtilis, Micrococcus luteus, Staphylococcus aureus and Staphylococcus epidermidis. Bioremediation experiments carried out on five batch reactors with different compositions but at same environmental conditions revealed that treatment T5 (boosted with the association of Bacillus subtilis, Micrococcus luteus) gave the best result in terms of oil and grease content removal (i.e. 67% in 63 days). In addition, these microorganisms were able of reducing the concentrations of heavy metals in the sample. Treatments T5, T3 (boosted with Bacillus subtilis only) and T4 (boosted with Micrococcus luteus only) gave optimum percentage uptakes of 65, 75 and 25 for Cu, Zn and Fe respectively.
Abstract: Introduction: This work is aimed to represent the use of the OPTI-JET CS MD1 MR prototype for application of neutral electrolyzed oxidizing water (NEOW) in magnetic resonance rooms. Material and Methods: We produced and used OPTI-JET CS MD1 MR aerosolisator whereby was performed aerosolization. The presence of microorganisms before and after the aerosolisation was recorded with the help of cyclone air sampling. Colony formed units (CFU) was counted. Results: The number of microorganisms in magnetic resonance 3T room was low as expected. Nevertheless, a possible CFU reduction of 87% was recorded. Conclusions: The research has shown that the use of EOW for the air and hard surface disinfection can considerably reduce the presence of microorganisms and consequently the possibility of hospital infections. It has also demonstrated that the use of OPTI-JET CS MD1 MR is very good. With this research, we started new guidelines for aerosolization in magnetic resonance rooms. Future work: We predict that presented technique works very good but we must focus also on time capacity sensors, and new appropriate toxicological studies.
Abstract: Problem of food preservation is extremely important
for mankind. Viscous damage ("illness") of bread results from
development of Bacillus spp. bacteria. High temperature resistant
spores of this microorganism are steady against 120°C) and remain in
bread during pastries, potentially causing spoilage of the final
product. Scientists are interested in further characterization of bread
spoiling Bacillus spp. species. Our aim was to find weather yeast
Saccharomyces cerevisiae strains that are able to produce natural
antimicrobial killer factor can preserve bread illness. By diffusion
method, we showed yeast antagonistic activity against spore-forming
bacteria. Experimental technological parameters were the same as for
bakers' yeasts production on the industrial scale. Risograph test
during dough fermentation demonstrated gas production. The major
finding of the study was a clear indication of the presence of killer
yeast strain antagonistic activity against rope in bread causing
bacteria. After demonstrating antagonistic effect of S. cerevisiae on
bacteria using solid nutrient medium, we tested baked bread under
provocative conditions. We also measured formation of carbon
dioxide in the dough, dough-making duration and quality of the final
products, when using different strains of S. cerevisiae. It is
determined that the use of yeast S. cerevisiae RCAM 01730 killer
strain inhibits appearance of rope in bread. Thus, natural yeast
antimicrobial killer toxin, produced by some S. cerevisiae strains is
an anti-rope in bread protector.
Abstract: Strong anthropogenic impact has uncontrolled
consequences on the nature of the soil. Hence, up-to-date sustainable
methods of soil state improvement are essential. Investigators provide
the evidence that biochar can positively effects physical, chemical,
and biological soil properties and the abundance of mycorrhizal fungi
which are in the focus of this study. The main aim of the present
investigation is to demonstrate the effect of two types of plant growth
promoting bacteria (PGPB) inoculums along with the beech wood
biochar and mineral N additives on mycorrhizal colonization.
Experiment has been set up in laboratory conditions with containers
filled with arable soil from the protection zone of the main water
source “Brezova nad Svitavou”. Lactuca sativa (lettuce) has been
selected as a model plant. Based on the obtained data, it can be
concluded that mycorrhizal colonization increased as the result of
combined influence of biochar and PGPB inoculums amendment. In
addition, correlation analyses showed that the numbers of main
groups of cultivated bacteria were dependent on the degree of
mycorrhizal colonization.
Abstract: Strong anthropogenic impact has uncontrolled
consequences on the nature of the soil. Hence, up-to-date sustainable
methods of soil state improvement are essential. Investigators provide
the evidence that biochar can positively effects physical, chemical,
and biological soil properties and the abundance of mycorrhizal fungi
which are in the focus of this study. The main aim of the present
investigation is to demonstrate the effect of two types of plant growth
promoting bacteria (PGPB) inoculums along with the beech wood
biochar and mineral N additives on mycorrhizal colonization.
Experiment has been set up in laboratory conditions with containers
filled with arable soil from the protection zone of the main water
source “Brezova nad Svitavou”. Lactuca sativa (lettuce) has been
selected as a model plant. Based on the obtained data, it can be
concluded that mycorrhizal colonization increased as the result of
combined influence of biochar and PGPB inoculums amendment. In
addition, correlation analyses showed that the numbers of main
groups of cultivated bacteria were dependent on the degree of
mycorrhizal colonization.
Abstract: The development of composite materials and the
related design and manufacturing technologies is one of the most
important advances in the history of materials. Composites are
multifunctional materials having unprecedented mechanical and
physical properties that can be tailored to meet the requirements of a
particular application. Some composites also exhibit great resistance
to high-temperature corrosion, oxidation, and wear. Polymers are
widely used indoors and outdoors, therefore they are exposed to a
chemical environment which may include atmospheric oxygen, acidic
fumes, acidic rain, moisture heat and thermal shock, ultra-violet light,
high energy radiation, etc. Different polymers are affected differently
by these factors even though the amorphous polymers are more
sensitive. Ageing is also important and it is defined as the process of
deterioration of engineering materials resulting from the combined
effects of atmospheric radiation, heat, oxygen, water, microorganisms
and other atmospheric factors.
Abstract: The application of cold Radio-Frequency (RF) plasma
in the conservation of cultural heritage became important in the last
decades due to the positive results obtained in decontamination
treatments. This paper presents an equipment especially designed for cold RF
plasma application on paper documents, developed within a research
project. The equipment consists in two modules: the first one is
designed for decontamination and cleaning treatments of any type of
paper supports, while the second one can be used for coating friable
papers with adequate polymers, for protection purposes. All these
operations are carried out in cold radio-frequency plasma, working in
gaseous nitrogen, at low pressure. In order to optimize the equipment parameters ancient paper
samples infested with microorganisms have been treated in nitrogen
plasma and the decontamination effects, as well as changes in surface
properties (color, pH) were assessed. The microbiological analysis
revealed complete decontamination at 6 minutes treatment duration;
only minor modifications of the surface pH were found and the
colorimetric analysis showed a slight yellowing of the support.
Abstract: Batch production plants provide a wide range of
scheduling problems. In pharmaceutical industries a batch process
is usually described by a recipe, consisting of an ordering of tasks
to produce the desired product. In this research work we focused
on pharmaceutical production processes requiring the culture of
a microorganism population (i.e. bacteria, yeasts or antibiotics).
Several sources of uncertainty may influence the yield of the culture
processes, including (i) low performance and quality of the cultured
microorganism population or (ii) microbial contamination. For
these reasons, robustness is a valuable property for the considered
application context. In particular, a robust schedule will not collapse
immediately when a cell of microorganisms has to be thrown away
due to a microbial contamination. Indeed, a robust schedule should
change locally in small proportions and the overall performance
measure (i.e. makespan, lateness) should change a little if at all.
In this research work we formulated a constraint programming
optimization (COP) model for the robust planning of antibiotics
production. We developed a discrete-time model with a multi-criteria
objective, ordering the different criteria and performing a
lexicographic optimization. A feasible solution of the proposed
COP model is a schedule of a given set of tasks onto available
resources. The schedule has to satisfy tasks precedence constraints,
resource capacity constraints and time constraints. In particular
time constraints model tasks duedates and resource availability
time windows constraints. To improve the schedule robustness, we
modeled the concept of (a, b) super-solutions, where (a, b) are input
parameters of the COP model. An (a, b) super-solution is one in
which if a variables (i.e. the completion times of a culture tasks)
lose their values (i.e. cultures are contaminated), the solution can be
repaired by assigning these variables values with a new values (i.e.
the completion times of a backup culture tasks) and at most b other
variables (i.e. delaying the completion of at most b other tasks).
The efficiency and applicability of the proposed model is
demonstrated by solving instances taken from a real-life
pharmaceutical company. Computational results showed that
the determined super-solutions are near-optimal.
Abstract: Application of biochar to arable soils represents a new
approach to restore soil health and quality. Many studies reported the
positive effect of biochar application on soil fertility and
development of soil microbial community. Moreover biochar may
affect the soil water retention, but this effect has not been sufficiently
described yet. Therefore this study deals with the influence of
biochar application on: microbial activities in soil, availability of
mineral nitrogen in soil for microorganisms, mineral nitrogen
retention and plant production. To demonstrate the effect of biochar
addition on the above parameters, the pot experiment was realized.
As a model crop, Lactuca sativa L. was used and cultivated from
December 10th 2014 till March 22th 2015 in climate chamber in
thoroughly homogenized arable soil with and without addition of
biochar. Five variants of experiment (V1 – V5) with different regime
of irrigation were prepared. Variants V1 – V2 were fertilized by
mineral nitrogen, V3 – V4 by biochar and V5 was a control. The
significant differences were found only in plant production and
mineral nitrogen retention. The highest content of mineral nitrogen
in soil was detected in V1 and V2, about 250 % in comparison with
the other variants. The positive effect of biochar application on soil
fertility, mineral nitrogen availability was not found. On the other
hand results of plant production indicate the possible positive effect
of biochar application on soil water retention.
Abstract: Present work deals with the possible use of fertigation
in agriculture and its impact on the availability of mineral nitrogen
(Nmin) in topsoil and subsoil horizons. The aim of the present study is
to demonstrate the effect of the organic matter presence in fertigation
on microbial transformation and availability of mineral nitrogen
forms. The main investigation reason is the potential use of pretreated
waste water, as a source of organic carbon (Corg) and residual
nutrients (Nmin) for fertigation. Laboratory experiment has been
conducted to demonstrate the effect of the arable land fertilization
method on the Nmin availability in different depths of the soil with
the usage of model experimental containers filled with soil from
topsoil and podsoil horizons that were taken from the precise area.
Tufted hairgrass (Deschampsia caespitosa) has been chosen as a
model plant. The water source protection zone Brezova nad Svitavou
has been a research area where significant underground reservoirs of
drinking water of the highest quality are located. From the second
half of the last century local sources of drinking water show
nitrogenous compounds increase that get here almost only from
arable lands. Therefore, an attention of the following text focuses on
the fate of mineral nitrogen in the complex plant-soil. Research
results show that the fertigation application with Corg in a
combination with mineral fertilizer can reduce the amount of Nmin
leached from topsoil horizon of agricultural soils. In addition, some
plants biomass production reduces may occur.
Abstract: Mobil Producing Nigeria Unlimited (MPNU), a
subsidiary of ExxonMobil and the highest crude oil & condensate
producer in Nigeria has its operational base and an oil terminal, the
Qua Iboe terminal (QIT) located at Ibeno, Nigeria. Other oil
companies like Network Exploration and Production Nigeria Ltd,
Frontier Oil Ltd; Shell Petroleum Development Company Ltd; Elf
Petroleum Nigeria Ltd and Nigerian Agip Energy, a subsidiary of the
Italian ENI E&P operate onshore, on the continental shelf and in deep
offshore of the Atlantic Ocean, respectively with the coastal waters of
Ibeno, Nigeria as the nearest shoreline. This study was designed to
delineate the oil-polluted sites in Ibeno, Nigeria using
microbiological and physico-chemical characterization of soils,
sediments and ground and surface water samples from the study area.
Results obtained revealed that there have been significant recent
hydrocarbon inputs into this environment as observed from the high
counts of hydrocarbonoclastic microorganisms in excess of 1% at all
the stations sampled. Moreover, high concentrations of THC, BTEX
and heavy metals contents in all the samples analyzed corroborate the
high recent crude oil input into the study area. The results also
showed that the pollution of the different environmental media
sampled were of varying degrees, following the trend: ground water
> surface water > sediments > soils.
Abstract: Microbes have been used to solve environmental
problems for many years. The role of microorganism to sequester,
precipitate or alter the oxidation state of various heavy metals has
been extensively studied. Treatment using microorganism interacts
with toxic metal are very diverse. The purpose of this research is to
remove the mercury using Pseudomonas putida (P. putida), pure
culture ATTC 49128 at optimum growth parameters such as
techniques of culture, acclimatization time and speed of incubator
shaker. Thus, in this study, the optimum growth parameters of P.
putida were obtained to achieve the maximum of mercury removal.
Based on the optimum parameters of P. putida for specific growth
rate, the removal of two different mercury concentration, 1 ppm and
4 ppm were studied. From mercury nitrate solution, a mercuryresistant
bacterial strain which is able to reduce from ionic mercury
to metallic mercury was used to reduce ionic mercury. The overall
levels of mercury removal in this study were between 80% and 89%.
The information obtained in this study is of fundamental for
understanding of the survival of P. putida ATTC 49128 in mercury
solution. Thus, microbial mercury removal is a potential
bioremediation for wastewater especially in petrochemical industries
in Malaysia.
Abstract: Lignocellolusic material is a substance that is resistant to be degraded by microorganisms or hydrolysis enzymes. To be used as materials for biofuel production, it needs pretreatment process to improve efficiency of hydrolysis. In this work, chemical pretreatments on rice straw using three diluted organic acids, including acetic acid, citric acid, oxalic acid, were optimized. Using Response Surface Methodology (RSM), the effect of three pretreatment parameters, acid concentration, treatment time, and reaction temperature, on pretreatment efficiency were statistically evaluated. The results indicated that dilute oxalic acid pretreatment led to the highest enhancement of enzymatic saccharification by commercial cellulase and yielded sugar up to 10.67 mg/ml when using 5.04% oxalic acid at 137.11 oC for 30.01 min. Compared to other acid pretreatment by acetic acid, citric acid, and hydrochloric acid, the maximum sugar yields are 7.07, 6.30, and 8.53 mg/ml, respectively. Here, it was demonstrated that organic acids can be used for pretreatment of lignocellulosic materials to enhance of hydrolysis process, which could be integrated to other applications for various biorefinery processes.
Abstract: Essential oils have a significant antimicrobial activity.
These oils can successfully replace the antibiotics. So, the
microorganisms show their inefficiencies resistant for the antibiotics.
For this reason, we study the physicochemical analysis and
antimicrobial activity of the essential oil of Daucus carota. The
extraction is done by steam distillation of water which brought us a
very significant return of 4.65%. The analysis of the essential oil is
performed by GC / MS and has allowed us to identify 32 compounds
in the oil of D. carota flowering tops of Bouira. Three of which are in
the majority are the α-Pinene (22.3%), the carotol (21.7%) and the
limonene (15.8%).
Abstract: Paraffinic oils were submitted to microbial action. The
microorganisms consisted of bacteria of the genera Pseudomonas sp.
and Bacillus lincheniforms. The alterations in interfacial tension were
determined using a tensometer and applying the hanging drop
technique at room temperature (299 K ±275 K). The alteration in the
constitution of the paraffins was evaluated by means of gas
chromatography. The microbial activity was observed to reduce
interfacial tension by 54 to 78%, as well as consuming the paraffins
C19 to C29 and producing paraffins C36 to C44. The LIFirr technique
made it possible to determine the microbial action quickly.
Abstract: We assessed the ecology of the organic and mineral soil
layers of laurel-leaved (BB-1) and Cryptomeria japonica (BB-2 and Pw)
forests in the Kasugayama Hill Primeval Forest (Nara, Japan). The soil
respiration rate was higher in the deeper horizons (F and H) of organic
layers than in those of mineral soil layers, suggesting organic layers
may be where active microbial metabolism occurs. Respiration rates in
the soil of BB-1, BB-2 and Pw forests were closely similar at 5 and 10°C.
However, the soil respiration rate increased in proportion to
temperatures of 15°C or above. We therefore consider the activity of
soil microorganisms to markedly decrease at temperatures below 10°C.
At a temperature of 15°C or above, the soil respiration rate in the BB-1
organic layers was higher than in those of the BB-2 and Pw organic
layers, due to differences in forest vegetation that appeared to
influence several salient soil properties, particularly pH and the carbon
(C) and nitrogen (N) content of the F and H horizons.
Abstract: Fructo-oligosaccharides (FOS) are produced from
sucrose by Aureobasidium pullulans in yields between 40-60%
(w/w). To increase the amount of FOS it is necessary to remove the
small, non-prebiotic sugars, present. Two methods for producing
high-purity FOS have been developed: the use of microorganisms
able to consume small saccharides; and the use of continuous
chromatography to separate sugars: simulated moving bed (SMB). It
is herein proposed the combination of both methods. The aim of this
study is to optimize the composition of the fermentative broth (in
terms of salts and sugars) that will be further purified by SMB. A
yield of 0.63 gFOS.gSucrose^-1 was obtained with A. pullulans using low
amounts of salts in the initial fermentative broth. By removing the
small sugars, Saccharomyces cerevisiae and Zymomonas mobilis
increased the percentage of FOS from around 56.0% to 83% (w/w) in
average, losing only 10% (w/w) of FOS during the recovery process.
Abstract: The effect of the inclusion of thyme and rosemary
essential oils into chitosan films, as well as the microbiological and
physical properties when storing chitosan film with and without the
mentioned inclusion was studied. The film forming solution was
prepared by dissolving chitosan (2%, w/v), polysorbate 80 (4% w/w
CH) and glycerol (16% w/w CH) in aqueous lactic acid solutions
(control). The thyme (TEO) and rosemary (REO) essential oils (EOs)
were included 1:1 w/w (EOs:CH) on their combination 50/50
(TEO:REO). The films were stored at temperatures of 5, 20, 33°C
and a relative humidity of 75% during four weeks. The films with
essential oil inclusion did not show an antimicrobial activity against
strains. This behavior could be explained because the chitosan only
inhibits the growth of microorganisms in direct contact with the
active sites. However, the inhibition capacity of TEO was higher than
the REO and a synergic effect between TEO:REO was found for S.
enteritidis strains in the chitosan solution.
Some physical properties were modified by the inclusion of
essential oils. The addition of essential oils does not affect the
mechanical properties (tensile strength, elongation at break, puncture
deformation), the water solubility, the swelling index nor the DSC
behavior. However, the essential oil inclusion can significantly
decrease the thickness, the moisture content, and the L* value of
films whereas the b* value increased due to molecular interactions
between the polymeric matrix, the loosing of the structure, and the
chemical modifications. On the other hand, the temperature and time
of storage changed some physical properties on the chitosan films.
This could have occurred because of chemical changes, such as
swelling in the presence of high humidity air and the reacetylation of
amino groups. In the majority of cases, properties such as moisture
content, tensile strength, elongation at break, puncture deformation,
a*, b*, chrome, 7E increased whereas water resistance, swelling
index, L*, and hue angle decreased.
Abstract: This study presents an attempt to evaluate the
antioxidant potential and antimicrobial activity of methanolic extract,
and essential oils prepared from the leaves of sage (Salvia officinalis
L.). The content of polyphenol in the methanolic extracts from the
leaves of Salvia officinalis was determined spectrophotometrically,
calculated as gallic acid and catechin equivalent. The essential oils
and methanol extract were also subjected to screenings for the
evaluation of their antioxidant activities using 2, 2-diphenyl-1-
picrylhydrazyl (DPPH) test. While the plant essential oils showed
only weak antioxidant activities, its methanol extract was
considerably active in DPPH (IC50 = 37.29 μg/ml) test. Appreciable
total polyphenol content (31.25 mg/g) was also detected for the plant
methanol extract as gallic acid equivalent in the Folin–Ciocalteu test.
The plant was also screened for its antimicrobial activity and good to
moderate inhibitions were recorded for its essential oils, and
methanol extracts against most of the tested microorganisms.
The present investigation revealed that this plant had rich source
of antioxidant properties. It is for this reason that sage has found
increasing application in food formulations.
Abstract: The biosynthesis of nanoparticles by microorganisms,
on the contrary to chemical synthesis, is an environmentally-friendly
process which has low energy requirements. In this investigation, we
used the microorganism Geobacillus wiegelii, strain GWE1, an
aerobic thermophile belonging to genus Geobacillus, isolated from a
drying oven. This microorganism has the ability to reduce selenite
evidenced by the change of color from colorless to red in the culture.
Elemental analysis and composition of the particles were verified
using transmission electron microscopy and energy-dispersive X-ray
analysis. The nanoparticles have a defined spherical shape and a
selenium elemental state. Previous experiments showed that the
presence of the whole microorganism for the reduction of selenite
was not necessary. The results strongly suggested that an intracellular
NADPH/NADH-dependent reductase mediates selenium
nanoparticles synthesis under aerobic conditions. The enzyme was
purified and identified by mass spectroscopy MALDI-TOF TOF
technique. The enzyme is a 1-pyrroline-5-carboxylate dehydrogenase.
Histograms of nanoparticles sizes were obtained. Size distribution
ranged from 40-160 nm, where 70% of nanoparticles have less than
100 nm in size. Spectroscopic analysis showed that the nanoparticles
are composed of elemental selenium. To analyse the effect of pH in
size and morphology of nanoparticles, the synthesis of them was
carried out at different pHs (4.0, 5.0, 6.0, 7.0, 8.0). For
thermostability studies samples were incubated at different
temperatures (60, 80 and 100 ºC) for 1 h and 3 h. The size of all
nanoparticles was less than 100 nm at pH 4.0; over 50% of
nanoparticles have less than 100 nm at pH 5.0; at pH 6.0 and 8.0 over
90% of nanoparticles have less than 100 nm in size. At neutral pH
(7.0) nanoparticles reach a size around 120 nm and only 20% of them
were less than 100 nm. When looking at temperature effect,
nanoparticles did not show a significant difference in size when they
were incubated between 0 and 3 h at 60 ºC. Meanwhile at 80 °C the
nanoparticles suspension lost its homogeneity. A change in size was
observed from 0 h of incubation at 80ºC, observing a size range
between 40-160 nm, with 20% of them over 100 nm. Meanwhile
after 3 h of incubation at size range changed to 60-180 nm with 50%
of them over 100 nm. At 100 °C the nanoparticles aggregate forming
nanorod structures. In conclusion, these results indicate that is
possible to modulate size and shape of biologically synthesized
nanoparticles by modulating pH and temperature.