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A novel red-pigmented bacterium was isolated from a water sample collected at Osun River, Ede. Morphological and 16 S rRNA gene sequencing revealed that the bacterium is a strain of Brevundimonas olei, while its red pigment was identified using UV-visible, FTIR and GCMS as a derivative of propylprodigiosin. The maximum absorbance of 534 nm, the FTIR's 1344 cm- 1 peak of prodigiosin's methoxyl C-O interaction, and the molecular ions from GCMS confirmed the pigment's identity. The pigments production was temperature-sensitive (25 °C), lost at > 28 °C, and in the presence of urea and humus. In addition, the pigment turned pink in the presence of hydrocarbons, while its red colour was retained with KCN and Fe2SO4, and enhanced by methylparaben. Furthermore, the pigment is stable in high temperature, salt, and acidic conditions, but changed to yellow in alkaline solution. The pigment, identified as propylprodigiosin (m/z 297), demonstrated broad-spectrum antibacterial activities against clinically important strains of Staphylococcus aureus (ATCC25923), Pseudomonas aeruginosa (ATCC9077), Bacillus cereus (ATCC10876), Salmonella typhi (ATCC13311), and Escherichia coli (DSM10974). The ethanol extract has the highest zones of inhibition of 29 ± 3.0, 26 ± 1.2, 22 ± 3.0, 22 ± 1.5, and 20 ± 2.0 mm, respectively. Furthermore, the acetone pigments interacted with cellulose and glucose such that increasing glucose concentrations showed linearity at 425 nm. Finally, the fastness of the pigments to fabrics was excellent, with percentage fadedness of 0 and - 43% light and washing tests, respectively, in the presence of Fe2SO4 as the mordant. The antibacterial nature of prodigiosin solutions and their good textile fastness to fabrics could be essential in manufacturing antiseptic materials such as bandages, hospital clothing and agricultural applications such as tubers preservation.Key points.
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Identifying the dissemination patterns and impacts of a virus of economic or health importance during a pandemic is crucial, as it informs the public on policies for containment in order to reduce the spread of the virus. In this study, we integrated genomic and travel data to investigate the emergence and spread of the SARS-CoV-2 B.1.1.318 and B.1.525 (Eta) variants of interest in Nigeria and the wider Africa region. By integrating travel data and phylogeographic reconstructions, we find that these two variants that arose during the second wave in Nigeria emerged from within Africa, with the B.1.525 from Nigeria, and then spread to other parts of the world. Data from this study show how regional connectivity of Nigeria drove the spread of these variants of interest to surrounding countries and those connected by air-traffic. Our findings demonstrate the power of genomic analysis when combined with mobility and epidemiological data to identify the drivers of transmission, as bidirectional transmission within and between African nations are grossly underestimated as seen in our import risk index estimates.
Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , Nigéria/epidemiologia , SARS-CoV-2/genéticaRESUMO
Shiga toxigenic strains of E. coli (STEC) known to be etiological agents for diarrhea were screened for their incidence/occurrence in selected abattoirs sources in Osogbo metropolis of Osun State, Nigeria using a randomized block design. Samples were plated directly on selective and differential media and E. coli isolates. Multiplex PCR analysis was used to screen for the presence of specific virulence factors. These were confirmed serologically as non-O157 STEC using latex agglutination serotyping kit. Sequence analysis of PCR products was performed on a representative isolate showing the highest combination of virulence genes using the 16S gene for identification purposes only. Results showed that the average cfu/cm2 was significantly lower in the samples collected at Sekona-2 slaughter slab compared with those collected at Al-maleek batch abattoir and Sekona-1 slaughter slab in ascending order at P = 0.03. Moreover, the average cfu/cm2 E. coli in samples collected from butchering knife was significantly lower when compared with that of the workers' hand (P = 0.047) and slaughtering floor (P = 0.047) but not with the slaughter table (P = 0.98) and effluent water from the abattoir house (P = 0.39). These data suggest that the abattoir type may not be as important in the prevalence and spread of STEC as the hygiene practices of the workers. Sequence analysis of a representative isolate showed 100% coverage and 96.46% percentage identity with Escherichia coli O113:H21 (GenBank Accession number: CP031892.1) strain from Canada. This sequence was subsequently submitted to GenBank with accession number MW463885. From evolutionary analyses, the strain from Nigeria, sequenced in this study, is evolutionarily distant when compared with the publicly available sequences from Nigeria. Although no case of E. coli O157 was found within the study area, percent occurrence of non-O157 STEC as high as 46.3% at some of the sampled sites is worrisome and requires regulatory interventions in ensuring hygienic practices at the abattoirs within the study area.
Assuntos
Matadouros , Contaminação de Alimentos , Microbiologia de Alimentos , Carne/microbiologia , Escherichia coli Shiga Toxigênica/genética , Microbiologia Ambiental , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Genoma Bacteriano , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Nigéria/epidemiologia , Vigilância em Saúde Pública , Escherichia coli Shiga Toxigênica/classificaçãoRESUMO
Aim: The present study is focused on determining if there are differences in the types of organisms responsible for spontaneous fermentation in two types of cassava food products, namely, fufu and gari, while also ensuring that the expected organoleptic properties associated with the fermentation process from this study location is reproducible. Study Design: A Complete Randomized Design (CRD) with three replications was adopted and used to test for significant differences between the two cassava products. Place and Duration of Study: The roots of two cassava varieties namely, TMS 97/0211 (white pulp) and TMS 97/2205 (yellow pulp) were obtained from the International Institute for Tropical Agriculture (IITA), Ibadan, and were processed at Ede, Nigeria between March and May 2016. Methodology: Using standardized spontaneous fermentation methods, the two varieties of cassava, were sampled eight hourly over a period of 5 days, for lactic acid bacteria and fungi. Samples were incubated anaerobically, representative microbial populations were enumerated and identified using standard microbiological protocols. Proximate analysis and sensory evaluations were conducted. Results: The results showed that the predominant lactic acid bacterial organisms were Lactobacillus brevisand L plantarum. On the other hand, the representative lactic acid fungal isolates were identified as Neurospora crassa, Aspergillus fumigatus and Saccharomyces spp. Investigation of succession organisms revealed differences between the dry cassava finished product, gari and the wet finished product, fufu. The fungal organisms were the predominant starter organisms found in gari, while, the predominant starter organisms found in fufu were the bacterial types. Conclusion: The present results show that in spite of the spontaneity of the fermentation process, the yellow cassava variety supports the growth and reproduction of similar fermentation organisms as the white variety. Furthermore, the prevailing microenvironment in the fermentation set up, that is, wet or dry is the most important factor in determining the predominating organisms in the fermentation process and the organoleptic and nutritional characteristics of the final product. Results from this study show that it is possible to reproduce the organoleptic and nutritional characteristics peculiar to this test location using the isolated lactic acid microorganisms.
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Investment in Africa over the past year with regards to SARS-CoV-2 genotyping has led to a massive increase in the number of sequences, exceeding 100,000 genomes generated to track the pandemic on the continent. Our results show an increase in the number of African countries able to sequence within their own borders, coupled with a decrease in sequencing turnaround time. Findings from this genomic surveillance underscores the heterogeneous nature of the pandemic but we observe repeated dissemination of SARS-CoV-2 variants within the continent. Sustained investment for genomic surveillance in Africa is needed as the virus continues to evolve, particularly in the low vaccination landscape. These investments are very crucial for preparedness and response for future pathogen outbreaks. One-Sentence SummaryExpanding Africa SARS-CoV-2 sequencing capacity in a fast evolving pandemic.