Open Access Short Research Article

Comparative Analysis of Fatty Acid Composition in Some Saccharomyces cerevisiae Strains

Eslanda A. Khalilova, Svetlana Ts. Kotenko, Eivira A. Islammagomedova, Dinara A. Aliverdieva

Microbiology Research Journal International, Page 1-6
DOI: 10.9734/BMRJ/2016/26729

Aims: Comparative study of fatty acid composition of biomass in alcohol and wine S. cerevisiae strains, Champagne wine and ethanol, produced by yeast.

Place and Duration of Study: The study was undertaken in the Laboratory of Biochemistry and Biotechnology, Caspian Institute of Biological Resources, Russian Academy of Sciences, Russia. The duration of the study was the period of June 2015 to March 2016.

Methodology: Yeast strains were identified biochemically and by ITS rDNA gene sequencing. Capillary electrophoresis and gas-liquid chromatography were used for analyzing composition and content of carboxylic acids in the yeast biomass, Champagne wine and ethanol produced by yeast. 

Results: Comparative analysis of fatty acid composition in biochemically active yeasts S. сerevisiae Y-503, S. cerevisiae Y-3980 and S. cerevisiae Litto – Levure СHA showed that the distinctive feature of alcohol Y-503 strain from wine strains was the lack of 16 fatty acids, the predominance of eicosapolyene acids (up to 58.1% in biomass and 56.6% in ethanol) and almost half the content of saturated fatty acids. All strains were found to be predominated with palmitic (16:0) and linoleic (18:2ω-6) acids that is typical for yeast Saccharomyces. This pattern was observed in Champagne wine and ethanol.

Conclusion: The results of comparative analysis of fatty acid composition of new and traditionally used commercial yeast strains may be useful in the selection of strains in order to manufacture high quality products in winemaking and alcohol industry.

Open Access Original Research Article

A Comparative Study of the Bioremediation Potentials of Inorganic Nutrient Sources

T. Sampson, C. J. Ogugbue, G. C. Okpokwasili

Microbiology Research Journal International, Page 1-11
DOI: 10.9734/BMRJ/2016/26027

Aim: To evaluate the efficacy of inorganic nutrient sources in crude oil degradation.

Place and Duration of Study: The study was carried out at Environmental Microbiology Department, University of Port Harcourt, Nigeria, between January and June 2015.

Methodology: Hydrocarbon polluted soil was collected and recreated in three (3) containers marked A – C, representing NPK, Urea fertilizer and control, respectively. The setups were amended with NPK and urea fertilizer and observed for a 35 - day period. Hydrocarbon degradation in a 0.25% crude oil contaminated water was as well studied by inoculating a mineral salt – water (solution) with suspensions of a 24-h old pure cultures of bacterial isolates identified as Pseudomonas sp., Bacillus sp. and Micrococcus sp. Total petroleum hydrocarbons (TPH) and total hydrocarbon content (THC) was analyzed using gas chromatographic analysis and mass spectrometer – GC/MS.

Results: The percentage residual petroleum hydrocarbons in soil were closely related to each other when compared to the control setup, C. NPK was however, found to be more effective in the aquatic environment than urea. The kinetics studies in water showed the treatment options were effective in the descending order of percentage residual hydrocarbons; direct NPK, Aw - (20.3%) > direct urea, Bw - (23%) compared to the control, Cw - (45.2%). And a one-way analysis of variance, the Laverne’s test for homogeneity of variances and Tukey post hoc test showed there was a significant difference in the mean values of the various treatment options (p>0.05, f (2, 36) = 92.70, PV = 0.00).

Conclusion: In the overall, the efficacy of a fertilizer depends on the environment it found itself. However, urea fertilizer was observed to be slow-release in nature, hence if fertilizers must be applied directly, urea fertilizer is recommended.

Open Access Original Research Article

Detection of A2142G and A2143G Substitutions among Clarithromycin-resistant Helicobacter pylori Strains Isolated from Egyptian Patients

Eman A. El-Masry, Nahla A. Melake, Ahmed A. Salama, Amal F. Makled

Microbiology Research Journal International, Page 1-9
DOI: 10.9734/BMRJ/2016/26157

Background: Clarithromycin is the most commonly recommended antibiotic in Helicobacter pylori (H. pylori) eradication regimens, but the prevalence of clarithromycin-resistant H. pylori is increasing. Clarithromycin-resistance is associated with mutations in the 23S rRNA gene. The study aimed to examine gene mutations (A2142G and A2143G) of H. pylori 23S rRNA responsible for resistance to clarithromycin.

Materials and Methods: The study was carried out by collecting 53 H. pylori isolates. Isolation, identification and antimicrobial susceptibility to clarithromycin were done by standardized methods. Resistant strains were analysed for mutations in the 23S rRNA gene by polymerase chain reaction-based restriction fragment length polymorphism and sequencing.

Results: H. pylori isolates were recovered from 91.4% of studied patients. About 64% were clarithromycin-resistant strains. The minimum inhibitory concentration (MIC) values of all clarithromycin-resistant isolates ranged from 1.5 to 8μg/ml. Primary clarithromycin-resistant isolates only showed a single type of point mutation (A2143G). In contrast, secondary isolates had dual diversity of 23S rRNA gene mutation types (A2142G and A2143G).

Conclusion: Secondary clarithromycin-resistant isolates show a greater variety of 23S rRNA gene mutation types than primary isolates.

Open Access Original Research Article

Used Toothbrushes: Microbial Evaluation and Antibiotic Susceptibility Profiles of Associated Bacteria

Osungunna Michael Oluwole, Oyajoju Tolulope Olumuyiwa

Microbiology Research Journal International, Page 1-9
DOI: 10.9734/BMRJ/2016/26824

Aims: Toothbrush has been universally accepted as the most effective tool for removing harmful plaque and bacteria from mouth. On average, colonization of bacteria is reduced by 88.8% as a result of brushing. Toothbrush if not properly taken care of before, during and after use may serve as a vector for the re-introduction of potential pathogens into the oral cavity.

This study therefore aimed at investigating the microbial quality of used toothbrushes among selected students of a Tertiary Institution in Ile-Ife, Nigeria as well as the antibiotic susceptibility profiles and adherence property of the associated bacteria.

Methodology: Fifty used toothbrushes were collected from students in sterile nylon and transported to Laboratory for processing within an hour of collection. The bacteria were isolated and characterized by conventional biochemical techniques. Antibiotic susceptibility test was carried out using the disk diffusion test according to the Clinical and Standard Laboratory Institute guidelines. Phenotypic adherence property of the isolates was investigated using the Congo Red Agar (CRA) method.

Results: These revealed the presence of six genera of bacteria namely: Bacillus spp, Staphylococcal spp, Klebsiella spp, Enterobacter spp, Citrobacter spp and Serratia spp. Bacillus flexus was the predominant Gram-positive species accounting for 30.9% while Klebsiella oxytoca accounts for 26.5% as the predominant Gram-negative species. All the isolates were multidrug resistant. However, 22% of the isolates were adherent as they produced black crystalline colonies in Congo Red agar.

Conclusion: The study concluded that toothbrush should be adequately taken care of to prevent it from serving as vector for infection and re-infection of mouth. 

Open Access Original Research Article

Characterization of Detergent-compatible Alkaline Protease from Bacillus agaradhaerens MTCC 9416

Nandini Phanse, Ketna Matkar, Pragya Rathore

Microbiology Research Journal International, Page 1-14
DOI: 10.9734/BMRJ/2016/26065

Aim: The present work deals with the purification and characterization of an alkaline protease produced by an alkalophilic bacterium, Bacillus agaradhaerens and establishment of its suitability as detergent additive.

Methodology: Bacterial isolates producing alkaline protease were screened from diverse samples viz. soil, sewage and industrial effluents by enrichment culture technique. The taxonomic status and molecular characterization of the bacterium showing maximum alkaline protease activity was determined. The alkaline protease produced by the organism was purified its molecular size was determined by gel permeation chromatography. The purified enzyme was studied for its feasibility as detergent additive.

Results: The bacterium under study was identified as Bacillus agaradhaerens by CSIR Institute of Microbial Technology (IMTECH), Chandigarh, India and deposited with an accession number MTCC 9416. The genotypic characterization of the 16S ribosomal DNA gene was performed and the sequence was submitted to NCBI under the name Bacillus agaradhaerens strain nandiniphanse5 (NCBI Accession No: JN703504). The alkaline protease with a molecular weight of approximately 25 kDa, demonstrated optimum activity at 55°C and pH 10.5, stability in pH range 7.0 to 12.0. The enzyme exhibited increased thermostability in presence of 25 mM CaCl2, enhanced activity in presence of chlorides of Ca2+, Mg2+,  K+, Co2+ and Mn2+. The protease exhibited highest degradation of casein followed by gelatin as compared to other protein substrates. The kinetic parameters were estimated to be 77.82 U/ml (Vmax) and 6.66 mg/ml (Km) using casein as substrate. The alkaline protease was also checked for its blood stain removal ability. The thermostable alkaline protease retained its activity in presence of detergent components with desired level stability and compatibility and therefore has a potential to be used commercially in the detergent industry.

This is the first report on characterization of detergent-compatible alkaline protease from Bacillus agaradhaerens.

Open Access Review Article

Improvement of Health by Probiotics: The Roles on Human Gut and Immune Modulation

Anteneh Getachew, Admas Berhanu, Malaiyarasa Pandian

Microbiology Research Journal International, Page 1-14
DOI: 10.9734/BMRJ/2016/24586

The term probiotic refers to viable, non-pathogenic microorganisms when ingested in an adequate and controlled amount confer health benefits for the host. In present review, the beneficial effect of probiotics to human health is presented. Introduction section discuss details about backgrounds of probiotic, criteria associated with probiotic, mechanisms and beneficial effect on human gut and immune system and beneficial effects of probiotics on health. The review mainly focused on clinical studies with probiotics and different investigations are discussed in detail. On these regard many experimental studies have found that probiotics have specific effects for different diseases that have been studied are presented. This review also gives back ground on different strain of probiotics and introduces some harmful strains and there possible health related consequences.