Phylogenetic analyses of bacteria associated with the processing of iru and ogiri condiments.

Analysis of the bacterial community dynamics during the production of traditional fermented condiments is important for food safety assessment, quality control and development of starter culture technology. In this study, bacteria isolated during the processing of iru and ogiri, two commonly consumed condiments in Nigeria, were characterized based on phylogenetic analyses of the bacterial 16S rRNA gene. A total of 227 isolates were obtained and clustered into 12 operational taxonomic units (OTUs) based on 97% 16S rRNA gene similarity. The OTUs spanned three phyla (Firmicutes, Actinobacteria and Proteobacteria), and nine genera: Acinetobacter, Aerococcus, Bacillus, Enterococcus, Enterobacter, Lysinibacillus, Micrococcus, Proteus and Staphylococcus. OTUs closely related to species of Bacillus dominated the processing stages of both condiments. Although no single OTU occurred throughout iru processing stages, an OTU (mostly related to B. safensis) dominated the ogiri processing stages indicating potentials for the development of starter culture. However, other isolates such as those of Enterococcus spp. and Lysinibacillus spp. may be potential starters for iru fermentation. Presumptive food-borne pathogens were also detected at some stages of the condiments' processing, possibly due to poor hygienic practices. SIGNIFICANCE AND IMPACT OF THE STUDY: Iru and ogiri are important condiments used for flavour enhancement in foods and serve as protein substitutes in diets among rural populations across West Africa. Consumption of these condiments is growing, reinforcing the need to scale up their production. Production of these condiments includes spontaneous fermentation, which often leads to inconsistent product quality and unguaranteed safety. This study has demonstrated the bacterial succession in iru and ogiri processing and highlights species that could be selected and exploited for starter culture development. This study provides a starting point to produce quality and microbiologically safe iru and ogiri condiments.

Oxygen for children and newborns in non-tertiary hospitals in South-west Nigeria: A needs assessment.

BACKGROUND: Oxygen is important for the treatment of hypoxaemia associated with pneumonia, malaria, and other medical, obstetric, and surgical conditions. Access to oxygen therapy is limited in many of the high mortality settings where it would be of most benefit. METHODS: A needs assessment of 12 non-tertiary hospitals in south-west Nigeria, assessing structural, technical and clinical barriers to the provision of safe and effective oxygen therapy. RESULTS: Oxygen supply was reported to be a major challenge by hospital directors. All hospitals had some access to oxygen cylinders, which were expensive and frequently ran out. Nine (75%) hospitals used oxygen concentrators, which were limited by inadequate power supply and lack of maintenance capacity. Appropriate oxygen delivery and monitoring devices (nasal prongs, catheters, pulse oximeters) were poorly available, and no hospitals had clinical guidelines pertaining to the use of -oxygen for children. Oxygen was expensive to patients (median US$20/day) and to hospitals. Estimated oxygen demand is reported using both a constant mean-based estimate and adjustment for seasonal and other variability. CONCLUSIONS: Making oxygen available to sick children and neonates in Nigerian hospitals will require: improving detection of hypoxaemia through routine use of pulse oximetry; improving access to oxygen through equipment, training, and maintenance structures; and commitment to building hospital and state structures that can sustain and expand oxygen initiatives.

Effect of baking improvers on the quality of whole cassava biscuits.

Improving agents such as ascorbic acid, sodium metabisulphite, sorbic acid and soyflour were used in the production of whole cassava biscuits. Cassava flour and small amount of soyflour were produced. Bulk density, water binding capacity and amylograph viscosity of cassava flour were determined. Mixing and dough extrusion time were recorded for each sample of biscuit dough developed with addition of improvers. Length, width and thickness of cut-out dough were measured before and after baking to evaluate biscuits flow. Proximate and sensory analysis of the biscuits samples was also determined. The result showed that, there was a slight decrease in mixing time, extrusion time, length and width of the biscuits samples prepared with improvers. However, there was a considerable increase in biscuits thickness. Amylograph result showed an improvement in flour stability and low retrogadation tendency, most especially flour with inclusion of ascorbic acid. Crude protein and fat increased with sample contained soyflour. Sensory evaluation result indicated no significant difference among the samples except the texture of the biscuits.

Microbiological Safety Assessment of Fermented Cassava Flour "Lafun" Available in Ogun and Oyo States of Nigeria.

The microorganisms involved in the fermentation and spoilage of fermented cassava flour were investigated. The water samples used at the different processing sites were also investigated to determine their safety status. There was predominance of Staphylococcus aureus, Aspergillus spp., and Escherichia coli in all samples. Coliforms were observed to be present in all of the processing water. In the fermented cassava flour, the total bacterial count ranged between 4.9 × 10(6) cfu/mL from Eleso, Bakatari, and Oja Odan processing sites and 8.10 × 10(6) cfu/mL in Eruku processing site. The majority of the microorganisms involved in the spoilage of "lafun" were found to be Aspergillus niger which ranged between 4.6 × 10(5) cfu/mL in Eleso and 8.1 × 10(5) cfu/mL in Kila. The control sample prepared in the laboratory had a low microbial load compared to samples collected from various sites and markets.

Significance of yeasts in the fermentation of maize for ogi production.

Saccharomyces cerevisiae, Candida krusei, C. tropicalis, Geotrichum candidum, G. fermentans and Rhodotorula graminis were isolated during the fermentation of maize for ogi production. All the isolates except Geotrichum fermentans and Rhodotorula graminis were able to degrade phytate. All the yeasts strains exhibited lipase and esterase activities. Only S. cerevisiae (2.60%) and C. krusei (7.41%) exhibited amylase activities. Candida sp. produced wider zone of inhibition than the other yeasts strains tested during lipase activity while S. cerevisiae strains produced significantly wider zone of clearing as compared to the other yeasts for esterase activities. The study of inter-relationships between Lactobacillus plantarum and yeasts (C. krusei and S. cerevisiae) showed that the growth of the yeast strains were enhanced during fermentation by the presence of the lactic acid bacteria, but the growth of the L. plantarum strain was significantly enhanced especially by the C. krusei.

Characteristics and significance of yeasts' involvement in cassava fermentation for 'fufu' production.

Six different strains of yeast, namely Candida krusei, C. tropicalis, Pichia saitoi, Saccharomyces cerevisiae, P. anomala and Zygosaccharomyces bailii were found present in cassava-fermenting water in the early part of the fermentation. The latter part of the fermentation was dominated in all cases by three strains of yeast namely C. krusei, C. tropicalis and Z. bailii. All the yeast strains exhibited amylolytic capabilities while none was able to produce cellulase. All the strains except Zygosaccharomyces spp. exhibited polygalacturonase activity, but only C. krusei was able to produce linamarase. In a study on the inter-relationships between C. krusei and Lactobacillus plantarum, the growth of the yeast strain was not enhanced in cassava by the presence of the lactic acid bacteria, but the growth of the L. plantarum strain was significantly enhanced when co-inoculated with C. krusei.

Extracellular enzyme activities during cassava fermentation for 'fufu' production.

Amylase and pectin methyl esterase activities increased rapidly during the early period of the fermentation of cassava for 'fufu' production, attaining their peak activities after 12 and 24h, respectively. Cellulase activity was lower and approximately constant for most of the fermentation period.