Characterization and probiotic potentials of lactic acid bacteria isolated from ingesta of selected ruminants

Studies were carried out to isolate and screen lactic acid bacteria with probiotic potentials and amylolytic activities from the ruminal ingesta of cow and goat. Ninety isolates obtained from the three abattoirs were divided into the following species: Lactobacillus plantarum, L. fermentum, L. pentosus, L. brevis, L. buchneri, L. collinoides, and Leuconostoc mesenteroides. The isolates were screened for probiotic potentials and amylolytic activities. Four isolates possessed probiotic potentials: L. plantarum CA3b, L. fermentum GA2d, L. plantarum GA1d, and L. plantarum GA3e. Lactobacillus plantarum CA3b, L. fermentum GA2d, and L. plantarum GA3e survived pH 2.5 and 3.5 after 180 min. Lactobacillus plantarum GA1d had the highest tolerance of 82.44% and 71.03% to 0.3% and 1% bile salts concentrations, respectively. Lactobacillus plantarum CA3b hydrolysed 3% starch with an average zone of clearance of 10.0 mm, while L. plantarum GA1d hydrolysed 2% with a zone of 9.5 mm. These two strains also possessed bacteriocin activities against E. coli, and were characterised based on their reactions to pH, temperature, and enzymes treatments. Ruminal ingesta of cow and goat harbour lactic acid bacteria possessing amylolytic and probiotic potentials, which can be exploited in the fermentation of feedstock, conferring health benefits and improved performance to these ruminants

Sourdough Bread from the Blend of Cassava, Sweet Potato, and Soybean Flours Using Lactobacillus plantarum and Pichia kudriavzevii

Sourdough is specialty bread made from a combination of flour, lactic acid bacteria, and yeasts. Composite flour of cassava, sweet potato, and soybean was used for the production of sourdough bread employing autochthonous lactic acid bacteria and yeasts isolated from the composite dough. The flour samples were assessed for functional properties, while the sourdough breads were evaluated for nutritional composition and organoleptic properties. The flour samples possessed good proximate profiles and phenolic contents. The lactic acid bacterium and yeast with the most desirable properties were identified as Lactobacillus plantarum and Pichia kurdriavzevii. Fermentation improved the nutritional indices of the composite sourdough bread samples. Lactobacillus plantarum SLC21 and P. kudriavzevii SYD17 bread had a shelf life of 7 days, while the control bread lasted for at least 4 days. Lactobacillus plantarum SLC21 and Pichia kudriavzevii SYD17 bread had the best overall acceptability. Utilisation of these local crops in a composite blend for sourdough will increase commercial profit for local farmers and developing economy. The composite blend will be of great importance in the preparation of pastries that do not require high gluten content. The strains exhibited great potentials for a better nutritional composition of the composite sourdough bread

Principles of contract claims management - A review of the Nigerian construction industry

This paper examines the management of contractual claims in the Nigerian construction industry. It explored issues bothering on availability of expertise in the area of managing claims, the principles of claims management, types of claims and their causes are carefully examined with a view to ascertain their potential impact on the execution of construction projects in Nigeria. The research methodology adopted in this paper involves the use of questionnaires administered to various professionals in the industry. The research revealed that there is a form of relationship that exists between pre-contract administration and claims management. The research also shows that administrative and socio-cultural factors, such as, absence of dedicated claims management experts, corruption and poor pre-contract documentation, respectively, amongst others, are mainly responsible for the knowledge gap in the industry. This paper recommends the development and subsequent implementation of a decision support system to aid practitioners in the area of managing construction contract claims

Microbiological, physicochemical and nutritional changes of millet for Koko production under different nixtamalisation conditions

Koko is a traditional fermented cereal gruel made from millet. Nixtamalisation is a traditional process by which cereals are cooked and steeped in lime. The microbiological and physicochemical changes of the millet used for koko production under different nixtamalisation conditions were investigated. The lactic acid bacteria isolated from the fermenting samples comprised Lactobacillus plantarum, Lactobacillus fermentum, Lactobacillus brevis, Pediococcus acidilactici and two genera of yeasts, namely Candida and Saccharomyces. There was a reduction in pH in all the samples; the spontaneous sample had the least of pH 3.9 at 72 h while the highest of pH 11.5 was observed in the 1.5% nixtamalised sample at 0h. The titratable acidity increased from 0.000mg/ml at 0h to 0.008mg/ml after 72 h at 0.75% nixtamalisation concentration. Selection was based on the proximate analyses of the fermenting samples. Nixtamalised samples at 1% and 1.5% had the highest crude fibre content (0.13% and 0.11%) and ash content (0.28% and 0.26%) respectively. Lactobacillus fermentum K048 (L.f) and Pediococcus acidilactici K1.548 (P.a) were selected as starter cultures. The controlled fermentation with starter cultures L.f + P.a had the highest crude protein content of 1.70% while the least of 0.39% was observed in 1.5% nixtamalised sample without starter culture. Sensory evaluation shows that controlled fermentation of 1.5% nixtamalised sample using L. fermentum K048 had the best general acceptability. Nixtamalisation made milling easier during processing by softening and swelling of the grains while inoculation with starter cultures enhanced the nutritional qualities of the grains for koko production.Keywords: Millet, nixtamalisation, koko, physicochemical, proximate analysi

Genetic diversity of Lactobacillus plantarum strains from some indigenous fermented foods in Nigeria

Lactobacillus plantarumhas been found to be commonly associated with Nigerian indigenous fermentedfoods. The intraspecies differentiation ofL. plantarumusing different molecular techniques is essential forthe selection of functional strains. In the present study, 48L. plantarumisolates from some Nigerianindigenous fermented foods; (gari, fufuandogi) were phenotypically characterized. The intraspeciesdiversity of 17 selectedL. plantarumstrains with good acidification rates, hydrogen peroxide productionand variation in carbohydrate fermentation patterns were carried out using molecular techniques,16S-23rDNA intergenic transcribed spacer and restriction fragment length polymorphism (ITS-PCR and ITS-RFLP), randomly amplified polymorphic DNA (RAPD) and pulsed-field gel electrophoresis (PFGE). TheITS-RFLP-HaeIII, RAPD-OPA5, OPA20 and PFGE-Sfi1 analysis showed genetic diversity among the strainsofL. plantarumisolated from the different fermented foods, and it can be established that these mo-lecular tools are useful for differentiation ofL. plantarumstrains. The molecular techniques used in thisstudy may be considered useful tools for characterization of isolates and for in-depth examination of thestrain diversity as the various strains isolated in this study can be used as adjunct and/or starter culturesin food fermentation processes

Extracellular polysaccharide from Weissella confusa OF126: Production, optimization, and characterization

The production, optimization, and characterization of exopolysaccharide (EPS) from Weissella confusa OF126 and the in-vitro probiotic potentials of this strainwas investigated. The EPS produced on sucrose modified-MRS broth was characterized. The purified EPS had an average molecularweight of 1.1 × 106 Da. HPLC analysis revealed the presence of glucose monomers, indicating its homopolysaccharide nature. The structural characteristics of the EPS were investigated by FTIR, and NMR spectroscopy. FTIR spectroscopy revealed the presence of hydroxyl, carboxyl, N-acetyl and amine groups. NMR analysis confirmed that the EPS contained α-(1 → 6) linkage and α-(1→3) branched linkage. The EPS showed strong in-vitro antioxidant activity. Four significant factorswere optimized using Central Composite Design (CCD) and Response Surface Methodology (RSM). The predicted optimum conditions for EPS production were cultivation time (48.50 h), sucrose concentration (24.00 g/L), pH (7.00) and yeast extract (2.50%).The EPS produced was predicted to be 3.10 g/L, while the experimental yield was 3.00 g/L. This strain was found to possess desirable probiotic attributes by its ability to survive at pH 2.0 and in the presence of bile salts (0.50% (w/v)) for 4 h. The results obtained from this study demonstrate W. confusa OF126 as a promising probiotic and the EPS produced can find useful applications in industries

Extracellular polysaccharide from Weissella confusa OF126: Production, optimization, and characterization

The production, optimization, and characterization of exopolysaccharide (EPS) from Weissella confusa OF126 and the in-vitro probiotic potentials of this strainwas investigated. The EPS produced on sucrose modified-MRS broth was characterized. The purified EPS had an average molecularweight of 1.1 × 106 Da. HPLC analysis revealed the presence of glucose monomers, indicating its homopolysaccharide nature. The structural characteristics of the EPS were investigated by FTIR, and NMR spectroscopy. FTIR spectroscopy revealed the presence of hydroxyl, carboxyl, N-acetyl and amine groups. NMR analysis confirmed that the EPS contained α-(1 → 6) linkage and α-(1→3) branched linkage. The EPS showed strong in-vitro antioxidant activity. Four significant factorswere optimized using Central Composite Design (CCD) and Response Surface Methodology (RSM). The predicted optimum conditions for EPS production were cultivation time (48.50 h), sucrose concentration (24.00 g/L), pH (7.00) and yeast extract (2.50%).The EPS produced was predicted to be 3.10 g/L, while the experimental yield was 3.00 g/L. This strain was found to possess desirable probiotic attributes by its ability to survive at pH 2.0 and in the presence of bile salts (0.50% (w/v)) for 4 h. The results obtained from this study demonstrate W. confusa OF126 as a promising probiotic and the EPS produced can find useful applications in industries