Peels of sweet potato (Ipomoea batatas) were buried in the soil for 14 days and the isolates associated with the degradation of the peels were obtained using standard microbiological procedures. The bacterial isolates obtained were screened for amylolytic and cellulolytic activities under different pH and temperatures as parameters and optimized for enzyme production. Sixteen (16) bacterial isolates were obtained and characterized and screened for amylase and cellulase production. Bacillus pumilus has the highest frequency of occurrence (18.75%) followed by B. subtilis (12.50%). After 24 to 48 h of incubation, B. pumilus produced highest concentration of amylase at 55°C, pH 6 (5.4 U/mL) while B. subtilis had the best cellulase production of 0.75 U/mL at 55°C, pH 7. B. pumilus and Bacillus subtilis produced the highest amylase and cellulase concentrations and seem to be the potential sources of these enzymes for industrial application.

Modernization has thrown humanity and other forms of life on our planet into a ditch of problems. Poverty, climate change, injustice and environmental degradation are a few of the shared global problems. The United Nations Sustainable Development Goals (SDGs) are the blueprint to achieve a better and more sustainable future for all. The SDGs are well structured to address the global challenges we face including poverty, inequalities, hunger, climate change, environmental degradation, peace and justice. Five years into the implementation, the SDGs have been driven mainly by international donors and ‘professional’ international development organizations. The world is left with 10 years to achieve these ambitious goals and targets. Various reviews show that little has been achieved overall, and the SDGs will not be a reality if a new strategy is not in place to bring inclusion. Microbiology, the scientific discipline of microbes, their effects and practical uses has insightful influence on our day-to-day living. We present how microbiology and microbiologists could increase the scorecard and accelerate these global goals. Microbiology has a direct link to achieving SDGs addressing food security, health and wellbeing, clean energy, environmental degradation and climate change. A non-classical growing relationship exists between microbiology and other SDGs such as peace, justice, gender equality, decent work and economic growth. The pledge of ‘Leave No One Behind’ will fast track progress and microbiology is in a better position to make this work.

This study was aimed at selecting starter cultures for bio-enriching ogi (fermented cereal gruel) using folate-producing microorganisms. The folate-producing microorganisms were isolated by incorporating folate analogue, methotrexate in the isolation medium and further screened for folate production by growth in Folic Acid Casei Medium. Folate production was quantified using 3-aminophenol spectrophotometric method. Folate-producing lactic acid bacteria from fermenting maize slurry were species of Lactobacillus, Lactococcus, Pediococcus and Leuconostoc while yeast isolates were mainly species of Candida and Saccharomyces. However, Lactobacillus plantarum X13, Pediococcus pentosaceus L73, Candida parapsilosis Y77 and Candida tropicalis Y74 were used as starter cultures singly and in combination for the fermentation and production of ogi. The highest folate concentration, 30.97 ± 0.37 μg/ml, was observed after 24 h of the co-fermentation of maize slurry with Lactobacillus plantarum X13 and Candida tropicalis Y74. This represents a triple fold of the folate concentration observed in unfermented maize slurry. The pH of the fermenting maize slurry was observed to decrease from 6.12 to 3.60, while the reducing sugars and the titratable acidities were observed to increase as fermentation progressed. Sensory evaluation of the ogi samples after fermentation showed high general acceptability comparable to the naturally fermented ogi as regards to colour, taste, flavour, aroma and texture. The data made available in this study suggest the possibility of folate enrichment of ogi and its use as a vehicle for increasing folate availability to consumers thereby preventing folate deficiency diseases prevalent in many African countries.

Cassava peels are rich in lignocellulolytic materials which are not readily amenable to enzymatic hydrolysis; hence, there is a need for a suitable pretreatment method that will support enzymatic hydrolysis. This study was designed to investigate lignocellulolytic organisms that would effectively support the bioconversion of organosolv pretreated cassava peels to fermentable sugars. Decaying cassava peels were collected into sterile bottles and microorganisms isolated, characterized and screened for lignocellulolytic enzymes production. Optimum temperature, pH and nutrient sources for enzyme production were determined. Organosolv pretreatment was carried out using methanol with varied concentration of catalyst (0.01 -3 M), reaction time (15 -60 min) and substrate size. Crude enzymes (cellulase and xylanase) from the isolates were added to the pretreated peels and bioconversion was monitored by measuring the concentration of reducing sugar and calculating the percentage peel hydrolysis. The fermentable sugars produced were quantified using gas chromatography. Pseudomonas fluorescens and Aspergillus terreus were isolated. P. fluorescens produces 2.8 u/mL of crude enzymes optimally at 50˚C and pH 8 while A. terreus produces 3.4 u/mL optimally at 40˚C, pH 6. Both isolates utilizes CarboxyMethylCellulose (CMC) and yeast extract as their best carbon and nitrogen sources. Highest percentage of peel hydrolysis was 67% for P. fluorescens at 0.01 M and 0.05 M for A. terreus (94%). Highest concentration of fermentable sugar was produced by A. terreus crude enzyme (331.79 mg/L glucose, 45.3 mg/L rhamnose and 46.52 mg/L xylose). P. fluorescens and A. terreus effectively supported the bioconversion of organosolv pretreated cassava peels to fermentable sugars.

Cassava (Manihot esculenta, Crantz) is one of the most important food plants in West Africa. Its peels are made up of cellulose, hemicellulose and lignin. This lignocellulolytic biomass can be converted using microbial enzymes to fermentable sugars which have wide range of biotechnological relevance in many fermentation processes. The aim of this study is to screen filamentous fungi from decaying cassava peels that are good producers of xylanases and cellulases. Decaying parts of cassava peels were obtained and brought to the laboratory for further work. Fungi were isolated, identified and screened for cellulase and xylanase production. Isolate with highest frequency of occurrence and enzyme production was identified using phenotypic and molecular method. Optimisation of growth conditions for enzymes production was monitored using the DNSA method, also saccharification of cassava peel were carried out using the enzymes obtained from the isolate. Aspergillus terreus KJ829487 was the predominant fungus. It produces cellulases and xylanases optimally at 40˚C, pH 6 and 8, utilising carboxymethylcellulose (CMC) or xylose and yeast extracts as its carbon and nitrogen sources respectively. Saccharification of the peels yielded 584 mg/L glucose, 78 mg/L xylose and 66 mg/L rhamnose. Aspergillus terreus KJ829487 obtained from cassava peels have the ability to produce high concentration cellulases and xylanases which effectively hydrolysed the lignocelluloses' biomass to fermentable sugars.

Introduction: Amylase, cellulase and protease are known for hydrolyzing starch, cellulose and protein respectively and these enzymes can be produced by microorganisms. A single bacterium with potential of producing amylase, cellulase and protease will be an organism of high industrial value. Aims: This work aimed at isolating bacteria that will be able to produce three extracellular enzymes (amylase, cellulase and protease). Methodology: Soil samples were collected from eight different locations within Ajayi Crowther University, Oyo Town, Nigeria. Bacteria were isolated from these soil samples and were identified using morphological and biochemical characteristics. Isolated bacteria were screened for their ability to produce amylase, cellulase and protease on plate and enzymes’ relative activities on plate were determined. Results: Forty two bacteria were isolated from soil samples and identified to belong to the Genera Bacillus (30), Enterobacter (6), Klebsiella (3) and Staphylococcus (3). Eight (19%), Eleven (26%) and Nineteen (45%) out of 42 isolated bacteria were able to produce amylase, cellulase and protease on plate with relative activities ranging from 1.25 – 2.88, 1.39 – 4.50 and 1.13 – 5.17 respectively. All the eight amylolytic isolates (Bacillus species (5) and Enterobacter species (3)) were able to produce the three enzymes (amylase, cellulase and protease). Conclusion: Eight bacteria with ability to produce three enzymes (amylase, cellulase and protease) were isolated from soil samples and could be further employed in enzyme-producing industries.

The current study was carried out on moulds associated with sequential deterioration of smoke-dried Clarias gariepinus stored at ambient temperature. Samples of smoke-dried catfish were obtained from street shops, commercial vendors and as well as from neighbouring rural markets where large percentage of population used to buy for consumption. Mould infestation, nutritional composition, pH and moisture content were determined in parallel at week 0, 3 and 6. Results of the study pointed that mould load increased with storage period and ranged from 2.00 x 102 to 11.31 x 102 cfu/g. The associated moulds were identified as Aspergillus flavus, A. versicolor, A. niger, A. fumigatus, Fusarium solani, Penicillium species and Mucor species.  As the storage duration advances at the ambient temperature, the associated moulds maintained sequential succession in the smoke-dried catfish. Specifically, A. flavus and A. versicolor succeeded A. niger and A. fumigatus till week 3, and A. flavus activated the succession till week 6. Unfortunately, apart from Penicillium commune that joined the activities of P. crysogenum at week 6, other moulds were not succeeded. The crude fat, fibre, protein and ash content decreased while the moisture content of the smoke-dried catfish gradually increased. Slightly acidic to neutral pH was maintained throughout the period of storage. Our study therefore revealed that sequential myco-deterioration of smoke-dried catfish is possible when stored for long period at ambient temperature.

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