Vol. 21(7) July 2017
Microbial fuel cell construction and comparative study
using different electrodes materials
Singh Samatha
The generation of renewable energy from waste water has
been demonstrated using a simple batch Microbial Fuel Cell (MFC) with different
industrial waste water. In the preliminary experiments, cheap copper electrodes
were used for anode and cathode chamber with Shewanella putrfaciens bacteria. The
efficiency obtained here is about 46%. In order to achieve better efficiencies,
construction of MFC is changed and copper electrodes are replaced with graphite
electrodes for their good ability of bio film formation. Two runs were conducted
with pharmaceutical waste and sewage waste for 15 days.
A fuel cell can be constructed with the environment in mind as well as keeping cost
down using cheap materials for construction without affecting the efficiency of
MFC. It is shown that mediator less MFCs are as efficient as normal MFC. In all
operating experiments, the MFCs are able to achieve high biological oxygen demand
(BOD) and chemical oxygen demand (COD) reduction of 85% and 82.5% with pharmaceutical
waste water and sewage waste water respectively. In both the cases Shewanella putrfaciens
are used as electron carriers for the transfer of electrons from bio film to electrodes.
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Degradation of Cypermethrin pesticide by using Indigenous
Bacteria isolated from pesticide contaminated Soil
Pawar A.S.* and Mali G.V.
Cypermethrin is a synthetic pyrethroid pesticide widely
used to control pests in cotton, fruits, and vegetable crops. In recent years, its
use has increased in the agricultural field for crop protection. It is genotoxic,
neurotoxic, immune-toxic and carcinogenic to mammals including humans. It adversely
affects the central nervous system and causes allergic skin reactions and eye irritation.
Problems arising due to toxicity and carcinogenicity are causing concerns for human
health, environment and ecosystem.
Bioremediation is solution for this problem. Therefore, the present work aimed with
the biodegradation of cypermethrin by using indigenous bacteria isolated from contaminated
soil. It describes the biodegradation of cypermethrin by bacterial isolate IK2a
which degrades cypermethrin into nontoxic metabolites like 2-propenoic acid[(4 methylphenyl)],
benzoic acid and chlorine. It was confirmed by the FTIR and GCMS analysis.
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Antibacterial and antioxidant activity of essential
oils of Ocimum basilicum leaves
Kavitha M.
The present study was designed to evaluate the antibacterial
activity against five bacterial pathogens and antioxidant activity of essential
oils from the leaves of Ocimum basilicum. Agar well diffusion was used to determine
the zone of inhibition and broth microdilution was used to determine the minimal
inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). The
antioxidant activity was ascertained using 2,2-Diphenyl-1-picryl hydrazyl (DPPH)
free radical scavenging assay.
The essential oils exhibited a great potential of antibacterial activity against
Staphylococcus aureus with the zone of inhibition of 21.5 mm when compared with
standard antibiotic with zone of inhibition of 19.5 mm. MIC and MBC values were
12.5 and 25 mg ml-1 respectively. The essential oils presented slightly high antioxidant
activity (IC50 = 28 µg ml-1) compared to gallic acid, a standard compound (IC50
= 25 µg ml-1). The results revealed that the essential oil of Ocimu basilicum could
be used as a source of natural antioxidant and antibacterial agent.
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Microwave accelerated solvent extraction of turmeric
oleoresin
Aniesrani Delfiya D.S.
Turmeric oleoresin can be obtained by the solvent extraction
of the ground turmeric powder with organic solvents like acetone, ethylene dichloride,
ethanol etc. One of the major drawbacks of solvent extraction is the lengthy extraction
time which results in consumption of more solvent and heat energy. Microwave heating
of turmeric powder prior to the solvent extraction can reduce the extraction time
and solvent requirement. In this study, the effect of various microwave exposure
times viz. 0, 1, 2, 3, 4, 5 and 6 min of turmeric powder on curcumin recovery, total
volatiles and non-volatiles of turmeric oleoresin was assessed. It was found that
dry turmeric powder irradiated in microwaves for 4 min recorded higher curcumin
(70.54 per cent) and oleoresin recovery (0.143 g/g of turmeric powder).
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Removal of Pb(II), Cd(II) and Zn(II) ions using a
new poly (1,3-cyclohexylene oxalate) polymer
Khalili Fawwaz*, Alregeb Faten and Sweileh Bassam Sweileh
A new polyoxalate polymer was synthesized by condensation
of 1,3-cyclohexandiol and oxalyl chloride in dry chloroform at 0-5oC. The polymer
was characterized by inherent viscosity, FT-IR, 1H-NMR, 13C-NMR, thermal analysis
and SEM. The removal characteristics of the polymer towards Pb(II), Cd(II) and Zn(II)
ions were studied by batch equilibrium technique as a function of pH, temperature,
metal concentration and contact time and as well as by column technique. The isothermal
characteristics, thermodynamics and kinetics data of the metal ions onto the polymer
were also investigated.
Langmuir, Freundlich and Dubinin-Radushkevich (D-R) adsorption models were applied
to describe the experimental data. The polymer showed high metal ion uptake towards
Pb(II) and Zn(II), but lower uptake one toward Cd(II). However, the polymer was
found to selectively adsorb Pb(II) and Zn(II) in the concentration variation isotherm
experiments. The metal-loaded polymer was regenerated by 0.10 M HNO3 which is more
efficient than 0.10 M EDTA.
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Allelopathic activity of Patrinia scabiosifolia and
Patrinia rupestris
Zorikova Olga, Manyakhin Artem,* Koldaev Vladimir, Moiseenko Larisa and Litvinova
Ekaterina
The focus of the research is allelopathic activity of
Patrinia scabiosifolia and Patrinia rupestris. Secondary metabolites of higher plants
which regulate growth are of interest as the basis for possible agents to be used
in crop production. In order to study the phytogenic field, soil samples were selected.
Gramineous and forb plant association soil was used as control. Cucumber seeds (Cucumis
sativus) were used as test culture to identify the allelopathic activity of the
phytopathogenic field. The activity of allelopathic substances contained in leaves,
inflorescences, stems and rhizomes of P. scabiosifolia and P. rupestris was monitored
by bioassays method, observing the impact of water extracts of plant material of
certain plant parts upon the growth of seedlings of the test cultures.
The results were analyzed by methods of mathematical statistics using Statistica
6.0. The bioassays of soil samples showed pronounced phyto-activity of the samples
tested which owes to secretions of parts of the donor plants. The results obtained
may be used for commercialization of P. scabiosifolia and P. rupestris material
as a source of biologically active substances possessing sedative and adaptogenic
properties, as well as in crop production. Metabolites of P. rupestris manifest
an inhibitory action with maximum impact on the test crop caused by generative parts
and leaves whereas the stem and underground parts show significantly smaller effect.
Metabolites of parts of P. scabiosifolia did not have a meaningful impact on germination
of test cultures and had a stimulating effect on the development of seedlings which
was most pronounced in cases of extracts of leaves and generative parts.
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Existing biological nitrogen removal processes and
current scope of advancement
Magdum Sandip* and Kalyanraman V.
In India, to achieve the stringent norms of total nitrogen
less than 10 mg/l in sewage treatment plant is a big challenge for the public -
private facilities and organizations. After successful implementation of this norm
the pollutant burden from rivers and natural water bodies certainly reduces. The
use of conventional biological nitrogen removal (BNR) processes for new treatment
facility development or retrofitting is also an energy and cost intensive practice.
The process technologies offered by current market such as MLE, MBBR, IFAS and SBR
are still in with downside of higher footprint, multi tank reactors, heavy instrumentation
for IR and RAS which ultimately incur higher capital and operating cost. The current
market need and lack of sustainable nitrogen removal applications, trigger to review
the of all available efficient biological nitrogen removal processes. This review
will gives an overall scenario of past and current biological nitrogen removal process
technologies with showing possible scope and way forward towards more energy neutral
nitrogen removal technologies.
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