11 research outputs found
Bacillus amyloliquefaciens AD 20 and Bacillus altitudinis AD14 Isolated from a Dye Pond Decolorize Synthetic Textile Reactive Dyes
A screen of textile effluents, receiving waterbodies, and waste sites near a textile factory was undertaken to isolate new bacteria strains capable of dye degradation. Out of the 45 isolates, two dye decolorizers, Bacillus altitudinis AD14 and B. amyloliquefaciens AD20, obtained from the sediment samples were identified by cultivation and 16S rRNA gene sequencing. Decolorization testing was performed under static aerobic conditions in the laboratory. The two Bacillus species showed dye decolorization capabilities on media containing each of these four commercial textile azo dyes- Reactive Blue 4 Red (RBFR), Cibacron Brilliant Orange 4 Red (COFR), Cibacron Brilliant Yellow 6 Percent Green (CYPGS), and Turquoise Cibacron Green (TCG). At the end of a ten-day incubation period, B. amyloliquefaciens AD20 was more efficient in dye reduction than B. altitudinis AD14 on CYPGS and COFR at a magnitude of four-fold and two-fold, respectively, while B. altitudinis AD14 only outperformed it in the TCG dye media. The isolates performed best on medium containing RBFR; the principal dye used by the textile factory. Genome annotation revealed the absence of plasmids and the presence of putative genes associated with dye decolorization, such as laccase and azoreductase
In vitro Antifungal Activity of Extracts of Moringa oleifera on Phytopathogenic Fungi Affecting Carica papaya
BACKGROUND: Plants remain the natural sources of efficacious phytonutrients with beneficial assets to mankind against microbial disorders. Diverse folklores have reported the roles of medicinal plants in the remedies of various disorders in man and animals. Metabolites and pesticides from the plant origin are considered better alternatives due to favorable environmental impact as compared to the synthetic counterparts. Significant economic losses and hindrance of global papaya production are due to fungal diseases. Phytochemicals have made medicinal plants become sources of environmentally friendly alternative antimicrobials.
AIM: This study aimed at assessing the antifungal activity of leaf extracts of Moringa oleifera against phytopathogenic fungi isolated from Carica papaya.
METHODS: n-Hexane, ethyl acetate, ethanol, methanol, and aqueous extracts of M. oleifera leaves were evaluated for their antifungal properties. Agar well-diffusion method was implemented for in vitro screening, minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of the extract types against fungal species of Aspergillus, Penicillium, Rhizopus, and Trichoderma.
RESULTS: All the extracts evaluated inhibited fungal growth to some degree, with the aqueous extract exhibiting more inhibitory activities than the organic extracts. There was significant inhibition of fungal development by the tested plant extracts at different concentrations. MIC of the extracts was 15.625 mg/ml while the MFC values ranged between 15.625 and 31.25. In this work, the antifungal activity of M. oleifera was found to be equal or higher than commercially available fungicide, ketoconazole.
CONCLUSION: The results of this study indicate that foliole extracts of M. oleifera have potential for use as biofungicides for plant protection against fungal diseases
Molecular Characterization of the Circulating Strains of Vibrio cholerae during 2010 Cholera Outbreak in Nigeria
This study aimed at characterizing the phenotypic and toxigenic status
of circulating strains of cholera during outbreaks in Nigeria,
employing molecular typing techniques. Two hundred and one samples of
rectal swabs, stool, vomitus, water (from the well, borehole, sachet,
stream, and tap) and disinfectants (sodium hypochlorite) were collected
from three states in the country. The samples were inoculated on
thiosulphate-citrate bile salt-sucrose (TCBS), Cary-Blair transport
medium and smeared on glass slides for direct examination. The Vibrio
cholerae isolates were serotyped, biotyped, and characterized using
PCR of the cytotoxin gene A (ctxA), wbeO1, and wbfO139 gene primer. Of
the 201 samples screened, 96 were positive for V. cholerae O1 (48%),
with 69 (72%) positive for ctxA gene. The results from this study
showed that the circulating strains of cholera in Nigeria were of Ogawa
serotype, also observed in other outbreaks in Nigeria (1991, 1992, and
1996). However, the strains were of the Classical biotype and were
mainly (72%) ctxA gene-positive. This current investigation has
confirmed the production of cholera toxin by the circulating strains,
and this could be harnessed for possible cholera vaccine production in
Nigeria
Fermentation Enhanced Biotransformation of Compounds in the Kernel of Chrysophyllum albidum
Chrysophyllum albidum Linn (African star apple) is a fruit with extensive nutritional and medicinal benefits. The fruit and kernel in the seed are both edible. Strains of lactic acid bacteria (LAB) were isolated from fermented seeds and assessed for probiotic characteristics. The extracts in both the unfermented and the fermented aqueous extracts from the kernels obtained from the seeds of C. albidum were subjected to analysis using the gas chromatography/mass spectrometry (GC-MS) method. This analysis identified the bioactive compounds present as possible substrate(s) for the associated organisms inducing the fermentation and the resultant biotransformed products formed. Three potential probiotic LAB strains identified as Lactococcus raffinolactis (ProbtA1), Lactococcus lactis (ProbtA2a), and Pediococcus pentosaceus (ProbtA2b) were isolated from the fermented C. albidum seeds. All strains were non hemolytic, which indicated their safety, Probt (A1, A2a, and A2b) grew in an acidic environment (pH 3.5) during the 48-h incubation time, and all three strains grew in 1% bile, and exhibited good hydrophobicity and auto-aggregation properties. Mucin binding proteins was not detected in any strain, and bile salt hydrolase was detected in all the strains. l-lactic acid (28.57%), norharman (5.07%), formyl 7E-hexadecenoate (1.73%), and indole (1.51%) were the four major constituents of the fermented kernel of the C. albidum, while 2,5-dimethylpyrazine (C1, 1.27%), 3,5-dihydroxy-6-methyl-2,3-dihydropyran-4-one (C2, 2.90%), indole (C3, 1.31%), norharman (C4, 3.01%), and methyl petroselinate (C5, 4.33%) were the five major constituents of the unfermented kernels. The isolated LAB are safe for consumption. The fermenting process metabolized C1, C2, and C5, which are possible starter cultures for the growth of probiotics. Fermentation is an essential tool for bioengineering molecules in foods into safe and health beneficial products
Application of a point-of-care test for the serodiagnosis of typhoid fever in Nigeria and the need for improved diagnostics
There is an urgent need for affordable point-of-care diagnostics for the differentiation of febrile illnesses and the confirmation of typhoid in endemic countries. Blood samples were collected from febrile patients with clinical suspicion of typhoid and screened for typhoid fever using the Widal and Typhi Dri Dot tests, while stool and blood samples were screened for Salmonella Typhi using the culture method as well as PCR as a confirmatory test. A high proportion of febrile patients from Lagos with clinical suspicion of typhoid fever reacted positively in a simple and rapid latex agglutination assay for typhoid fever, indicating that this illness is a common and presumably under-diagnosed health problem in this metropolis. Seropositivity was 19.2% in the rapid test compared with 22.9% in the classical Widal test. The confirmation of typhoid in these seropositive patients appeared cumbersome because of negative blood cultures and low DNA yield in molecular testing. A review of the literature revealed that in Nigeria seroprevalence rates can be high in the normal population and that pathogens other than S. Typhi are often isolated from the blood of seropositive febrile patients. The simplicity and the relatively high specificity (97.8%) of the rapid test as determined in a study performed in Indonesia calls for a further validation of this promising test for use in Afric
Molecular Characterization of the Circulating Strains of Vibrio cholerae during 2010 Cholera Outbreak in Nigeria
This study aimed at characterizing the phenotypic and toxigenic status
of circulating strains of cholera during outbreaks in Nigeria,
employing molecular typing techniques. Two hundred and one samples of
rectal swabs, stool, vomitus, water (from the well, borehole, sachet,
stream, and tap) and disinfectants (sodium hypochlorite) were collected
from three states in the country. The samples were inoculated on
thiosulphate-citrate bile salt-sucrose (TCBS), Cary-Blair transport
medium and smeared on glass slides for direct examination. The Vibrio
cholerae isolates were serotyped, biotyped, and characterized using
PCR of the cytotoxin gene A (ctxA), wbeO1, and wbfO139 gene primer. Of
the 201 samples screened, 96 were positive for V. cholerae O1 (48%),
with 69 (72%) positive for ctxA gene. The results from this study
showed that the circulating strains of cholera in Nigeria were of Ogawa
serotype, also observed in other outbreaks in Nigeria (1991, 1992, and
1996). However, the strains were of the Classical biotype and were
mainly (72%) ctxA gene-positive. This current investigation has
confirmed the production of cholera toxin by the circulating strains,
and this could be harnessed for possible cholera vaccine production in
Nigeria