Vol. 5(2) May 2010
Recovery of Hydrogen and Methane from Wastewater using
a Two-Stage UASB System
Pisutpaisal Nipon, Tanikkul Pinanong and Boonyawanich Sirione
Abstract: Biological
hydrogen and methane production from a sucrose-containing synthetic wastewater was
setup in a two stage up-flow anaerobic sludge blanket (UASB) system. Thermally pretreated
UASB granule was used as an inoculated seed in a 1 L hydrogenogenic reactor (first
stage) whereas non thermally pretreated UASB granule was used as the inoculated
seed in a 1.5 L methanogenic reactor (second stage). All experiments were conducted
under the room temperature (30±3oC) and fixed influent pH of 5.5 for the hydrogenogenic
reactor and that of 7.0 for the methananogenic reactor. The hydrogenogenic reactor
was operated at varied hydraulic retention time (HRT) and organic loading rates
(ORL) whereas the methanogenic reactor was operated at fixed hydraulic retention
time of 12 hr and OLR dependent on the COD effluent from the hydrogenogenic reactor.
In the hydrogenogenic stage, hydrogen productivity, production rate and COD removal
efficiency of 21.87 mM g-1 COD, 1.8 L d-1 and 49.23% were optimally achieved at
operational condition of HRT 6 h with OLR of 6.5 g COD d-1. Methane productivity,
production rate and COD removal efficiency of 96.00 mM g-1 COD, 2.9 L d-1 and 87.40%,
respectively were observed in the methanogenic stage. Overall performance of combined
two stage system is 90% with respect to COD removal efficiency.
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Isolation of a Novel Bacteria Bacillus pantothenticus
8063, Capable of Natural Rubber Latex Degradation
Cherian Elizabeth and Jayachandran K.
Abstract: In an
attempt to select a potent rubber degrading strain, several bacterial strains were
isolated. After the primary screening, the selected 50 strains were identified of
which the dominant strains were Pseudomonas sp. and Bacillus sp.. The bacterial
strains were subjected to grow on mineral salt latex medium as well as mineral salt
latex agar medium. Of these, the bacterial isolate Bacillus pantothenticus could
grow well on the agar medium, was also found to reduce the latex content of the
mineral salt latex medium considerably. Scanning Electron Micrographs of the rubber
surface proved its ability to grow on latex. This organism was selected for further
studies in the biodegradation of natural rubber latex.
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Regeneration Studies using Nodal Explant in Balanites
aegyptiaca (L.) Del. -An Endangered Medicinal Plant
Kamble Kaveri M. and Srinath Rao
Abstract: In vitro
studies were initiated for developing an efficient protocol callus induction and
direct regeneration using different explants of Balanites aegyptiaca (L.) Del. Callus
induction and direct regeneration of shoots was observed on MS basal medium supplemented
with various concentrations of auxins and cytokinins. Callus induction was higher
in leaf explants compared with other explants. Leaf explant produced maximum amount
of callus on MS medium supplemented with 1.0 mg/l 2, 4-D + 1.0 mg/l BAP compared
to other combinations used. Multiple shoots were induced from nodal explants on
MS medium fortified with 1.5 mg/l BAP (10 ± 2 per culture) and subsequent rhizogenesis
was achieved on MS + 0.5 mg/l IBA.
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Studies of Antimicrobial Activity of Turmeric (Curcuma
Longa L.) Leaves and Rhizomes collected during Plant Growth Phases
Shirgurkar M. V. and Thengane S. R.
Abstract: Turmeric
is the processed underground rhizome used as spice, herbal medicines, dying agent
and cosmetics. The leaves and rhizomes of this plant were collected at periodic
intervals. These samples were air dried, powdered and extracted with MeOH and EtOH.
Antibacterial activity of these extracts was determined against three different
index microbes, gram-positive cocci, gram-negative rod and cocci using well diffusion
method with appropriate controls. Antimicrobial activity of the 4-month-old leaves
was found to be the maximum while that of mature and fresh rhizomes was the maximum
against both gram-positive and Gram-negative bacteria.
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Protective Role of the Apigenin against Tinidazole
Induced Genotoxic Damage in Cultured Human Lymphocytes
Siddique Yasir Hasan and Afzal Mohammad
Abstract Tinidazole has been reported mutagenic in various
test systems, besides having anti-protozoal properties. In the present study the
effect of apigenin was studied against the genotoxic doses tinidazole using chromosomal
aberrations and sister chromatid exchanges as a parameter in cultured human peripheral
blood lymphocytes. A significant dose dependent decrease in chromosomal aberration
and sister chromatid exchange was observed when the tinidazole genotoxic doses treatments
were given along with the non-genotoxic doses of apigenin. The results suggest a
protective role of apigenin against the tinidazole genotoxic doses.
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Determination of Genome Size of Bhim Kol (Musa balbisiana)
Zaman M. and Konwar B.K.
Abstract Musa balbisiana is perhaps one of the progenitors
of the commercial banana. It is widely distributed in North East India. Economic
importances of this plant as well as morphological traits were studied. DNA from
M. balbisiana was isolated and restriction digestion was done to check the purity
and clean nature of the DNA sample. Mostly, the genome size is determined by using
flow cytometry but genome size can also be determined by microscope, which is the
easiest and less expensive method than the flow cytometry. The genome size of the
plant was determined approximately 0.62 pg per haploid set of chromosome (1.24 pg
/ 2C). Among, the Musa species the genome size of M.balbisiana is the smallest.
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Assessment of Aqueous Extracts of Selected Nepali
High Altitude Medicinal and Aromatic Herbs as Antimicrobial Agents against Selected
Gram-Negative and Gram-Positive Opportunistic Pathogens
Dixit S.M., Upadhyaya J., Dulal P., Poudel S., Dhakal A., Gautam P., Malla D., Manandhar
A., Pandey S., Shrestha P. and Pokhrel B. M.
Abstract Research in medicinal and aromatic herbal extracts
against representative gram-negative and gram-positive widely occurring bacterial
pathogens was carried out. Results of Growth Kinetic Broth Assay (GKBA), using Escherichia
coli (TUTH strain) and Enterococcus faecalis (TUTH strain) as target bacteria indicated
that a number of herbal extracts were able to affect growth of both bacterial strains
at two different growth periods 4h and 7h. Out of 22 herbal extracts assessed for
growth inhibitory activity against E. coli at both time points, 10 extracts showed
significantly different (p<0.05) absorbance values under spectroscopic measurements
compared to controls. This value was less when same extracts were assessed against
E. faecalis, with 6 extracts inhibiting growth significantly (p<0.05). Interestingly,
growths promoting activities, rather than growth inhibitory activities towards the
bacterial strains were also exhibited by certain herbal extracts at different time
points indicating prebiotic-like functionality of those herbs.
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Homology Modeling and Structure based Validation of
Mtb-Ddla of M.Tuberculosis
Kasturi K. and Suresh Kumar C.
Abstract: Mycobacterium
tuberculosis (Mtb), the main causative organism of Tuberculosis (TB), is a successful
pathogen that overcomes the numerous challenges presented by the immune system of
the host. TB remains one of the world's greatest causes of mortality and morbidity,
with approximately 8 million new infections and 2 million deaths per year. More
adults die due to TB every year than AIDS and malaria together. In the last 40 years
few anti-TB drugs have been developed, while the drug-resistance problem is increasing;
there is thus a pressing need to develop new anti-TB drugs active against both the
acute and chronic growth phases of the mycobacterium. D-alanine-D-alanine ligase
(ddla) is a key enzyme involved in the synthesis of peptidoglycan membrane. As an
anti-TB drug target, Mtb–ddla has been well validated. A homology model of ddla
has been constructed using the X-ray structures of S.aureus ddla (PDB code: 2I80)
as template, by comparative protein modeling principles. The resulting model has
the correct stereochemistry as assessed from the Ramachandran plot. The structurally
and functionally important residues (active site) of Mtb–ddla have been identified
using the S.aureus ddla crystal structure. Selective and specific Mtb–ddla inhibitors
can be designed using the homology model, by the structure-based drug design approaches.
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Effect of Growth Regulators on Micropropagation of
Rauvolfia Serpentina (L.) Benth
Harisaranraj R., Suresh K.* and Saravana Babu S.
Abstract: Rauvolfia
serpentina (L.) Benth. called Sarpagandha (the snake root) in Hindi, belongs to
family Apocynaceae. This plant is listed in earliest Ayurvedic medicinal text the
Charaka Samhita (c. 700 B.C.) and has been used since in olden days for the treatment
of mental illness and insomnia. The roots of R. serpentina contain numerous alkaloids.
Its indiscriminate use and poor method of conventional propagation have led this
species to be included in the list of endangered plants. Thus a need arises to generate
an efficient protocol for cloning of R. serpentina in order to regenerate propagules
to replenish depleting forests and meeting the demand of commercial cultivation.
The present study reveals the development of an efficient and simple process for
large-scale clonal micropropagation of selected plants of R. serpentina and their
successful field establishment. In vitro shoot multiplication from nodal explants
of Rauvolfia serpentina was standardized by using MS) medium13 supplemented with
a cytokinin (BA or Kin). Inclusion of NAA in the culture medium along with BA promoted
a higher rate of shoot multiplication. The mean number of shoots per explant after
4 weeks of culture was maximum (5.21) on the MS medium supplemented with 2.0 mg
l-1 BA and 0.25 mg l-1 NAA. The elongated shoots rooted within 7-8 days in ½ strength
MS medium supplemented with 0.25 mg l-1 of NAA and 2% (w/v) sucrose. About 85% of
the rooted plantlets survived acclimatization and transfer to the greenhouse. The
present study paves a way for conservation and propagation of this important medicinal
plant.
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Somaclonal Variations in an Endangered and Medicinally
Important Cucurbit, Citrullus Colosynthis (L.) Schrad
Shasthree T. and Mallaiah B.
Abstract: Somaclonal
variations were studied in in vitro regenerated plants of an endangered cucurbit,
Citrullus colosynthis (L.) commonly known as ‘bitter apple’. It is a medicinally
important plant used as a antirheumatic, anthelminthic and its exractive ‘colosynth’
is a very strong laxative. Roots are used in urinary diseases, mammalitis and opthalmia.
Its exract cucurbitacin glucosides inhibit growth of human breast cancer.
During in vitro mutagenesis and regeneration studies,
a number of somaclones have been isolated and characterized. Regenerated plants
from R0 are scored for the identification of variant plants in R1 and R2 generation.
During these studies a number of variations in habit, leaf and tendrillar character,
floral somaclones like androecious, gynoecious, andro monoecious and andro gynoecious
were isolated. Variation in fruit number, sizes, colours and seed coat colours were
also screened.
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Polyphenol Analysis and Antitumor activity of Crude
Extracts from Tegmen of Artocarpus Heterophyllus
Rajendran Nanda Kumar and Ramakrishnan Jayapradha
Abstract: Artocarpus
heterophyllus are rich sources of the isoprenylated phenolic compounds including
flavonoids. In this study, crude extracts from the tegmen of A. heterophyllus were
tested in vitro for their antitumor activity. Total polyphenol content of the extracts
ranged from 97.33 to 117.75 mg gallic acid equivalent (GAE) /g extract depending
on the solvent used and extraction time applied. Among the three solvent extracts,
methanol extract showed maximum polyphenol content at 2 hr extraction time followed
by ethanol and butanol respectively. The methanolic extract showed maximum cytotoxicity
on HEp2 cells up to 1:4 dilutions. Cytotoxic changes observed was cell aggregation,
cell rounding and cell death. The overall result indicates the promising baseline
information for the potential uses of crude extract from the tegmen of A. heterophyllus
as an antitumor agent.
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A Mathematical Model for Ethanol Fermentation by Mutant
Neurospora Crassa
Shanmuga Prakash M.
Abstract: The fermentation
kinetics of ethanol by Neurospora crassa was studied in a batch system. A simple
model was proposed using the logistic equation for growth, the Luedeking–Piret equation
for ethanol production and Luedeking–Piret-like equation for cellulose consumption.
The model appeared to provide a reasonable description for each parameter during
the growth phase. The production of ethanol was growth-associated.
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Differences in Biochemical and Electrophoretic Properties
of Lactobacillus Plantarum on Adaptation to GIT Conditions with Functional Pproperties
Agrawal Renu, Vanaja G., Gotcheva Velitchka and Angelov Angel
Abstract: The lactic
acid bacteria Lactobacillus Plantarum(LB) was initially isolated from Bulgarian
pickle. The culture strain has been adapted to GIT conditions (like tolerance to
low acid, pH 2.0) and high bile salt concentration (4%) and was coded as LBcfr.
It was also studied for the antimicrobial properties and antibiotic resistance.
Antagonistic property was found against toxic food pathogens like Klebsiella sp.,
Citrobacter sp., S. typhi, L. mono-cytogens, S. paratyphi, Shigella sp., Pseudomonas
sp., S. aureus, E.coli and L. greyii. The adapted strain (LBcfr) not only had higher
antimicrobial activity than the parent strain (LB) but was also found active against
additional toxic food pathogens like S.typhi, L. monocytogens, S.paratyphi, S. aureus
and L. greyii. The presence of S- layer protein at 30, 60 and 70 KD and good adherence
property (as tested by different solvents) in LBcfr culture strain makes it a potential
probiotic strain. It also had high antioxidant activity (47.60%) as assayed by DPPH
scavenging assay. All these properties make the probiotic culture strain (LBcfr)
to be used in the functional foods to impart beneficial effects.
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Review Paper: Possibilities of Existence of Weird
Life without Conventional Biochemistry
Rajalakshmi S. and Varatharaju G.
Abstract: Life
on mother earth is diverse to a great extent, which none could even imagine of,
but all organisms ranging from simple unicellular organism to intricate human beings
possess a shared Biochemistry (carbon based metabolism, liquid water as biosolvent,
DNA as genetic material) inherited from a common ancestor. But it had now been revealed
that life is possible in forms different from those on earth, referred to as ‘weird
life’ possessing a new alternative Biochemistry of life. There is always a possibility
that there are still organisms that tell something about early life and even possibly
the origin of life. Although man has ravaged deep into life, even up to molecular
or even nano level interactions and biosignalling there is so much about earth life,
which we do not understand. Nothing would be more tragic in the exploration of space
than to encounter an alien life but fail to recognize it.
The problem behind all these is that it is difficult to look for life, which we
do not know because we do not know how to look for it. While man is looking for
life outside earth, he looks for earth like life. Thus the encountered alien life
is left unrecognized and without his knowledge, man is posing serious contamination
to earth by serving as a transporter of alien weird life through his missions to
the space. Thus the search for weird life claims much significance owing to the
consequences of contamination and lack of proper tools and scientific preparations
in order to meet the consequences.
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