https://journalmrji.com/index.php/MRJI/issue/feed Microbiology Research Journal International 2023-01-20T08:18:30+00:00 Microbiology Research Journal International contact@journalmrji.com Open Journal Systems <p style="text-align: justify;"><strong>Microbiology Research Journal International (ISSN:&nbsp;2456-7043)</strong> is dedicated to publish research papers, reviews, and short communications in all areas of Microbiology such as virology, mycology, parasitology, bacteriology, clinical microbiology, phycology, parasitology, protozoology, microbial physiology, immunology, microbial genetics, medical microbiology, microbial pathogenesis and epidemiology disease pathology and immunology, probiotics and prebiotics, veterinary microbiology, environmental microbiology, microbial ecology, microbially-mediated nutrient cycling, geomicrobiology, microbial diversity and bioremediation, evolutionary microbiology, enzymology, industrial microbiology, aeromicrobiology, food microbiology, molecular and cellular microbiology, entomology, biomedical sciences, pharmaceutical microbiology, agricultural microbiology, soil microbiology, zoology, endocrinology, toxicology, water microbiology, generation microbiology and nano microbiology. By not excluding papers based on novelty, this journal facilitates the research and wishes to publish papers as long as they are technically correct and scientifically motivated. The journal also encourages the submission of useful reports of negative results. This is a quality controlled, OPEN peer-reviewed, open-access INTERNATIONAL journal.</p> https://journalmrji.com/index.php/MRJI/article/view/1351 The Influence of Agitation Rates, pH and Calcium Carbonate on L-lysine Production by Bacillus subtilis using Agricultural Products as Carbon and Nitrogen Sources 2023-01-17T09:04:57+00:00 J. Okpalla judyzuby@yahoo.com I. A. Ekwealor <p>L-Lysine is an essential amino acid that is required in the diet of humans and animals. It is utilized in human medicine, cosmetics and pharmaceutical industry. ’The influence of agitation rates, pH and calcium carbonate on L-lysine production by Bacillus subtilis using&nbsp; agricultural products as carbon and nitrogen sources was studied. The L-lysine-producing bacteria had already been isolated from Nigerian soil. They were purified and Identified as <em>B. subtilis </em>PR13 and <em>B. subtilis</em> PR9, using cultural, biochemical and molecular characteristics. Optimization of some parameters which included agitation rates, pH values and CaCO<sub>3</sub> concentrations, on L-lysine production by the <em>Bacillus </em>species was carried out. The L-lysine was produced in 250 ml flasks containing fermentation media (FM1 and FM2). The findings revealed that, enhanced L-lysine yield of 2.10 and 1.33 mg/ml was observed at agitation rate of 180 rpm for <em>B. subtilis </em>PR13 and PR9 respectively. There was a positive correlation between agitation rates and L- lysine production by <em>B. subtilis </em>PR13 and PR9 (r = 0.96 and 0.83 respectively). The pH of 7.5, stimulated optimum L- lysine yield of 2.27 mg/ml for PR13 and 1.38 mg/ml for PR9. There was a positive correlation between pH values and L-lysine production by <em>B. subtilis </em>PR13 and PR 9 (r = 0.63 and 0.50 respectively). The supplementation of 40g/l of CaCO<sub>3</sub>, enhanced optimum L-lysine yield of 2.18 mg/ml for <em>B. subtilis </em>PR 13 and 1.30 mg/ml for <em>B. subtilis </em>PR9. There was a positive correlation between varying concentrations of calcium carbonate and L-lysine production by the <em>B. subtilis </em>PR13 (r =0.35), while negative correlation was observed for <em>B. subtilis </em>PR 9 (r = -0.10). The results obtained in the study illustrated that the optimization of process parameters could increase the L-lysine yield from agricultural products by <em>B. subtilis </em>PR13 and <em>B. subtilis </em>PR9.</p> 2022-12-29T00:00:00+00:00 ##submission.copyrightStatement## https://journalmrji.com/index.php/MRJI/article/view/1352 Molecular Characterization, Optimization and Production of PHA by Indigenous Bacteria Using Alternative Nutrient Sources as Substrate 2023-01-18T07:48:21+00:00 B. N. Dienye bb4blessing@yahoo.com O. K. Agwa G. O. Abu <p>Polyhydroxyalkanoates (PHA) are renewable, biodegradable biopolymer intracellularly accumulated by wide array of microorganisms as carbon reserve. This study investigates the influence of various cultural conditions on PHA production by a recently isolated local species under submerged fermentation. Six PHA producing strains were identified by 16S rDNA gene sequencing and strain <em>Priestia flexa</em> OWO1 showed satisfactory PHA productivity. The effects of production parameters were investigated and extraction of PHA was carried out using sodium hypochlorite method and maximum amount was detected after 72h. Maximum PHA production was obtained at incubation period of 48h, pH of 7.0 and temperature of 30<sup>o</sup>C. Amongst the hydrolysate of agro waste used, brewers spent grain (BSG) gave maximum yield of 3.01g/L while beans bran powder gave the highest PHA yields of 3.9 g/L amongst the organic nitrogen sources tested.&nbsp; Analysis of the crude PHA by Fourier Transform Infrared Spectroscopy (FT-IR) showed the presence of methyl, methylene as well as carbonyl functional groups. PHA production was higher after optimizing the production conditions as compared to basal medium therefore the utilization of these cheap renewable resources as alternative substrates for production of PHA make the process cost effective and sustainable.</p> 2022-12-29T00:00:00+00:00 ##submission.copyrightStatement## https://journalmrji.com/index.php/MRJI/article/view/1353 Comparative Roles of HBB5 Biosurfactant and Poultry Wastes in Polyaromatic Hydrocarbon Biodegradiation of Crude Oil-contaminated Sediment 2023-01-20T08:18:30+00:00 I. L. Nkwocha nkwochail@yahoo.com L. O. Odokuma C. J. Ogugbue <p>The comparative study of poultry wastes- and HBB5 biosurfactant-mediated polyaromatic hydrocarbon biodegradation in sediment polluted with crude oil were investigated. The experiments were carried out for a period of 28 days by monitoring pH, nitrate, phosphate, polycyclic aromatic hydrocarbon and microbiological parameters using standard procedures. The pH values obtained ranged between 6.21 and 6.93 in days 1 and 28 for the most effective treatment recipes. Generally, there was depletion in the concentrations of nitrate and phosphate for all set ups, but the most effective recipe witnessed highest reduction. For the polycyclic aromatic hydrocarbons, the recipe with highest limiting nutrients depletion also recorded the most hydrocarbon loss, and yet highest increase in density of hydrocarbonoclastic bacteria and fungi. The sample containing polluted sediment + poultry wastes + HBB5 biosurfactant recorded PAH values of 1932.6472ppm on day 1 and 481.2272ppm on day 28. Total hydrocarbon-utilizing bacterial counts ranged from 1.48×10<sup>4</sup> cfu/g to 9.70×10<sup>6</sup> cfu/g, while hydrocarbon-utilizing fungal counts ranged between 2.30×10<sup>3</sup> cfu/g and 3.90×10<sup>5</sup> cfu/g. From the results obtained, poultry wastes combined with HBB5 biosurfactant recorded the highest efficiency in the biodegradation of polycyclic aromatic hydrocarbons in sediments, and HBB5 biosurfactant in isolation recorded higher degradation efficiency for polyaromatic hydrocarbons than the degradation effect mediated by poultry wastes alone. It is therefore recommended that a combination of surface-active agent, nutrient amendment source and viable microbial biomass be adopted and employed as potent recipe for the degradation of polyaromatic hydrocarbons in crude oil-contaminated sediments.</p> 2022-12-29T00:00:00+00:00 ##submission.copyrightStatement##