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Articles
by
M.N. Igwo-Ezikpe |
Total Records (
4 ) for
M.N. Igwo-Ezikpe |
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H.A. Ogbunugafor
,
F.U. Eneh
,
A.N. Ozumba
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M.N. Igwo-Ezikpe
,
J. Okpuzor
,
I.O. Igwilo
,
S.O. Adenekan
and
O.A. Onyekwelu
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Oil was extracted from Moringa oleifera Lam (Moringaceae) seeds collected from Enugu, South-East Nigeria and evaluate its physico-chemical and antioxidant properties in comparism to palm oil. M. oleifera seeds gave oil yield of 41.47%. Refractive index, melting point (oC) and acid value (mg KOH g-1) of M. oleifera oil were 1.471±0.00, 28±0.00, 3.80±0.28 while palm oil had 1.473±0.00, 31±0.00, 6.20±0.35 respectively. Similarly, iodine (I2 100 g-1), saponification (mg KOH g-1) and peroxide (mMol kg-1) values obtained for M. oleifera oil were 85.30±0.25, 171.90±0.56 and 8.10±0.07 whereas palm oil had 34.70±0.13, 210.50±0.00 and 13.40±0.28 respectively. Total phenol (mg Gallic Acid Equivalent g-1), total flavonoids (mg Rutin Equivalent g-1) and total antioxidant capacity (mg Ascorbic Acid Equivalent g-1) were 40.17±0.01, 18.24±0.01, 37.94±0.02 for M. oleifera oil and 62.32±0.04, 33.13±0.03, 68.27±0.02 for palm oil respectively. M. oleifera oil and palm oil showed a concentration dependent DPPH free radical scavenging and reducing power capabilities. This study has shown that Moringa Oleifera gave high oil yield, which has good antioxidant capacity with potential for industrial, nutritional and health applications, therefore large scale cultivation of this economic plant could be used as poverty alleviation strategy in Nigeria. |
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M.N. Igwo-Ezikpe
,
O.G. Gbenle
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M.O. Ilori
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J. Okpuzor
and
A.A. Osuntoki
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Bacteria isolated from various contaminated soils in
Nigeria were investigated for their potential to utilize and biodegrade
high molecular weight polycyclic aromatic hydrocarbons which include chrysene,
fluoranthene and pyrene. Biochemical and morphological studies identified
the isolates as Sphingomonas sp., Pseudomonas sp. and
Pseudomonas putida. Biodegradation studies showed that Sphingomonas
sp., Pseudomonas sp. and P. putida degraded 100 mg L-1
chrysene to 30.5±0.3, 40.6±0.7 and 17.2±0.2
mg L-1, respectively after 8 days of incubation. Similarly,
fluoranthene was degraded to 2.0±0.1, 2.0±0.4 and 0.12±0.1
mg L-1 while pyrene to 0.16±0.2, 6.5±0.3 and
6.6±0.4 mg L-1 correspondingly. Consortium of the isolates
degraded 100 mg L-1 chrysene, fluoranthene and pyrene, respectively
to 21.3±0.9, 2.2±0.8 and 10.6±0.8 mg L-1.
In the presence of phenanthrene as co-substrate, chrysene, fluoranthene
and pyrene were, respectively degraded by consortium to 12.4±0.5,
0.2±0.3 and 0.7±0.2 mg L-1 while phenanthrene
was undetectable. This study showed that there was delayed degradation
of chrysene and fluoranthene in the presence of phenanthrene, this may
account for the persistence of these compounds in polycyclic aromatic
hydrocarbons polluted sites. This is the first report on the potential
of these isolates simultaneous utilization and biodegradation of chrysene,
fluoranthene and pyrene when used as sole carbon and energy source. |
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M.N. Igwo-Ezikpe
,
O.G. Gbenle
,
M.O. Ilori
,
J. Okpuzor
and
A.A. Osuntoki
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The experiment was conducted to evaluate the potential of
tropical bacterial isolates and its consortium to biodegrade mixture of high
molecular weight polycyclic aromatic hydrocarbons (chrysene, fluoranthene and
pyrene). The effect of phenanthrene in the degradation was also investigated.
The bacterial consortium was made up of Sphingomonas sp., Pseudomonas
sp. and P. putida and biodegradation set up for 8 days with
initial 100 mg L-1 substrate concentration. Degradation by Sphingomonas
sp., Pseudomonas sp. and P. putida, respectively after
8 days gave higher residual chrysene of 40.2±1.4, 40.3±2.2 and
27.4±1.8 mg L-1, fluoranthene of 32.5±1.3, 35.4±1.2
and 10.1±2.5 mg L-1 and pyrene of 37.5±1.2, 34.2±2.4
and 32.0±1.2 mg L-1 compared to 11.5±1.4 (chrysene),
6.2±1.3 (fluoranthene) and 6.0±1.8 (pyrene) mg L-1
obtained using the bacterial consortium. When the media was supplemented with
100 mg L-1 phenanthrene, after 8 days of degradation by bacterial
consortium residual chrysene, fluoranthene and pyrene was 0.45±0.25,
0.02±0.02 and 0.20±0.14 mg L-1, respectively while
phenanthrene was undetectable. No statistical significant (p < 0.05) difference
was obtained between degradation by bacterial consortium and consortium via
co-metabolism with phenanthrene rather they had a strong correlation of r =
0.99. The results suggest that bacterial consortium may be useful for the decontamination
of sites polluted with high molecular weight polycyclic aromatic hydrocarbons
due to synergistic effect. |
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M.N. Igwo-Ezikpe
,
O.G. Gbenle
,
M.O. Ilori
,
J. Okpuzor
and
A.A. Osuntoki
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Alcaligenes faecalis was evaluated for its potential to degrade varying concentrations of chrysene and diesel oil with concomitant biosurfactant production. Biodegradation was set up for 7 days utilizing the substrates as sole carbon and energy sources. Residual chrysene obtained after degradation of 30, 50 and 100 mg L-1, respectively was 17.4±1.5, 27.2±1.2 and 28.7±1.4 mg L-1 while total petroleum hydrocarbon remaining after degradation of 3, 5, 15 and 30% (v/v) diesel oil respectively was 2.58±0.5, 3.09±1.2, 21.65±5.4 and 63.92±8.1%. Microbial cells of A. faecalis and sterilized cell-free extract from diesel oil media showed emulsifying activities against kerosene, diesel oil, engine oil, hexadecane, dodecane, xylene and hexane whereas no emulsifying activity was observed of microbial cells and sterilized cell-free extract from chrysene media. Alcaligenes faecalis cells harvested from diesel oil media also showed haemolytic activity unlike the microbial cells from chrysene media. Growth of the isolate in chrysene and diesel oil media induced secretion of protein and carbohydrate into the media which were statistically significantly (p<0.05) different compared to controls. This study portrays the potential of Alcaligenes faecalis to degrade and grow on chrysene and diesel oil and induce extracellular protein and carbohydrate with concomitant production of biosurfactant for industrial purposes and in hydrocarbon bioremediation. |
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