Open Access Original Research Article

Comparative Studies on Citrullus vulgaris, Citrullus colocynthis and Cucumeropsis mannii for Ogiri Production

B. J. Akinyele, O. S. Oloruntoba

Microbiology Research Journal International, Page 1-18
DOI: 10.9734/BMRJ/2013/2337

Aim: This study investigated the microbiological, physicochemical and antinutritional properties of three varieties of fermenting melon seeds namely: Citrullus vulgaris (Schrad), Citrullus colocynthis (L) and Cucumeropsis mannii (Naud) for ogiri production.
Methodology: Ogiri was produced from these three varieties of melon seeds following the traditional fermentation process while online monitoring was used to evaluate microbial hazards using standard microbiological techniques. Physicochemical and antinutritional properties were determined using standard methods.
Results: Bacterial counts ranged from 7.0 x 103 cfu/g to 2.4 x 104 cfu/g for Citrullus vulgaris, 3.2 x 105 cfu/g to 3.7 x105 cfu/g for Citrullus colocynthis and 8.7 x 106 cfu/g to 9.1 x 106 cfu/g for Cucumeropsis mannii. Some of the isolated microorganisms from the fermenting melon seeds include Lactobacillus species, Bacillus species, Aerococcus viridans, Staphylococcus aureus, Micrococcus luteus, Aspergillus niger, Penicillium species and Fusarium eguseti. Cucumeropsis mannii had the highest crude fibre and protein (12.7 and 38.5 mg/g) but lowest values for fat and ash while Citrullus vulgaris recorded the highest values of 35.3 and 3.4 mg/g There were no significant differences in values obtained for sodium, Cucumeropsis mannii had highest values for potassium and phosphorus (0.36 and 0.29 mg/kg). Citrullus vulgaris was outstanding in mineral content for magnesium with the highest value of 0.27 mg/kg and lowest for calcium (0.29 mg/kg) compared to 0.30 and 0.34 for Cucumeropsis mannii and Citrullus colocynthis respectively. Anti-nutrients were highest in Citrullus vulgaris and lowest in Cucumeropsis mannii. Acidic pH of 5.78 was recorded in Citrullus colocynthis but increased to 8.91 and 8.69 in Citrullus vulgaris and Cucumeropsis mannii indicating that Citrullus colocynthis may not be appropriate for ogiri production.
Conclusion: Cucumeropsis mannii compares favourably with traditionally used Citrullus vulgaris resulting in higher fibre, protein, mineral contents with lower values of anti-nutrients and therefore recommended as a good substitute for ogiri production.

Open Access Original Research Article

In vitro Screening of Herbal Extracts and Antibiotics against Bacteria Isolated from Fish Products at Retail Outlets

Ume- Kalsoom, Sundus Siddique, Nosheen Shahzad, Tahseen Ghous, Saiqa Andleeb

Microbiology Research Journal International, Page 19-31
DOI: 10.9734/BMRJ/2013/2390

Aims: Many studies have been conducted on the antibacterial activity of medicinal plants against human pathogens. However, a little has been done on fish pathogens. The aim of this research work was to isolate bacterial pathogens from spoiled fish leading to human diseases and compare the efficacies of selected antibiotics and medicinal herbal extracts against these infectious pathogens.
Study Design: An experimental study.
Place and Duration of Study: Biotechnology Lab, Department of Zoology, University of AJ&K, Muzaffarabad, Pakistan, between Feb 2011 and August 2012.
Methodology: Bacterial pathogens Enterobacter amnigenus, Serratia odorifera, Salmonella Typhimurium and Shigella flexneri were isolated from spoiled fishes. Various extracts of seed and stem parts of medicinal plants including Cinnnamomum zylanicum, Cuminum cyminum, Syzygium aromaticum, Curcuma long Linn, Trachyspermum ammi and Momordica charantia (both seeds and green parts of Bitter gourd) against common fish associated bacterial pathogens by filter disc diffusion method.
Results: The highest zone of inhibition was observed by Ciprofloxacin against S. Typhimurium (61 mm), whereas 55 mm by Gentamicin and 51 mm by Streptomycin against S. flexneri. However, Penicillin G, Ampicillin, and Amoxicillin had no effect on S. flexneri and E. amnigenus. The extracts of green part of M. charantia showed better results as compared to the seed extracts. Phytochemical screening of medicinal plants indicated that individual compounds viz., thyme from ajwain, ar-turmerone from turmeric, eugenol, taninns and flavonoids from clove have antimicrobial activities.
Conclusion: Current study supports the traditional use of medicinal plants as antibacterial agents.

Open Access Original Research Article

Inhibitory Effects of Phenolic Monomers on Methanogenesis in Anaerobic Digestion

K. Kayembe, L. Basosila, P. T. Mpiana, P. C. Sikulisimwa, K. Mbuyu

Microbiology Research Journal International, Page 32-41
DOI: 10.9734/BMRJ/2013/2291

Aims: The purpose of this study was to evaluate the inhibitory effects of phenolic monomers on methanogenesis in anaerobic digestion and to assess the effect of hydroxyl groups’ number of phenolic monomers (aromatic structure) on inhibition of methane production by acetoclastic methanogens (archaea).
Study Design: Anaerobic digestion of pig manure, anaerobic toxicity essay, The effect of the hydroxyl group’s number on the methanogenic toxicity as exhibited by monomeric tannins, Correlation of the methanogenic toxicity (IC50) with aromatic compounds hydrophobicity (logPoct), Correlation of the methanogenic toxicity (IC50) with Cresols boiling point (bp).
Place and Duration of Study: Department of Chemistry, University of Kinshasa (DR Congo), between September 2011 and May 2012.
Methodology: The toxicity to acetoclastic methanogenic bacteria was performed with the standard method of serum bottles; digested pig manure was utilized as inoculums and acetate as substrate. The methane gas volume produced was measured by serum bottles liquid displacement systems (Mariotte flask system).
Results: The results of this study indicate that an increase in the number of hydroxyl groups on the aromatic compound was associated with a decrease in the compound’s toxicity to methanogens (archea). The toxicity of various phenolic monomers are decreasing in the following order: pyrogallol < hydroquinone < resorcinol < phenol < benzene with 3172, 2745, 1725, 1249 and 209 mg/l IC50 values respectively. A significant negative linear correlation between the toxicity of phenolic monomers together with the reference compound (benzene) and their hydrophobicity was found. Moreover, a high positive linear correlation has been found between the IC50 values of phenolic monomers and their boiling temperatures.
Conclusion: The obtained results indicate that relationships exist between the phenolic monomers structure and their inhibitory effects in methane biosynthesis. The analysis of experimental results suggests that an increase in the number of hydroxyl groups on the aromatic compounds was associated with a decrease in the phenolic monomers toxicity.

Open Access Original Research Article

Microbes, Mineral Elements and Geophysical Nature of Public Water Sources in Akungba-Akoko, Nigeria

A. O. Ajayi

Microbiology Research Journal International, Page 58-72
DOI: 10.9734/BMRJ/2013/2215

Aims: To determine the bacteriological quality and geophysical abiotic components including mineral elements of public drinking water sources in Akungba-Akoko community located in South West Nigeria.
Study Design: Water and soil samples were collected from selected ground water (e.g., well, borehole) and surface water (e.g., streams) in 20 various locations of Akungba-Akoko community. Similarly, Geographical positioning system (GPS) of the sampling site was determined.
Methodology: Total bacteria and coliform content of water samples were enumerated using the pour plate technique. The physico-chemical parameters such as pH, turbidity and temperature and mineral elements constituents were determined. Total bacterial count, phosphorus (P) and copper (Cu) were also determined in the soil samples.
Results: The total bacterial count ranged from as low as 1.0 x 102 cfu/mL in GLAS site to 1.22 x 106 cfu/mL in sample site GLA9, while the coliforms count ranged from 5.0 x 101 cfu/mL in well water of sample site GLG1 to 36 x 104 cfu/mL and 3.8 x 105 cfu/mL in sample site GL9 and GL7 respectively. As for soil sources, the total heterotrophic bacterial count range was from 1.8 x105 cfu/g to 8.7 x105 cfu/g. Total hardness of the water sources ranged from 4.46 ppm in sample site GLA2 to 216.86 ppm in well water (GLWS 6) in Akungba. High levels of lead in some areas as in Araromi pond zone (GLCW16) and Well water 2nd Market (GLBWS 6) among others, exceeded the maximum permissible level of 0.10 mg/L. The pH of water sources range from pH 5.52 to pH 7.91 while temperature ranges from 23ºC to 28ºC.
Conclusion: This study shows that many sources of public drinking water supply in Akungba-Akoko are microbiologically substandard with possible infiltration of some chemical contaminants. Hence, routine monitoring and protection of the water resources is necessary in this community to improve the quality of drinking water and avoid possible associated health risks.

Open Access Original Research Article

Microbial Occurrence and Distribution at Different Rhizosphere Depths of Musa sapientum var parasidiaca and Senna occidentalis

J. A. Grillo, B. O. Opere, B. A. Adeniyi

Microbiology Research Journal International, Page 73-83
DOI: 10.9734/BMRJ/2013/2204

In this study, we focussed on the isolation, enumeration, distribution and occurrence of rhizomicroflora of Musa sapientum var parasidiaca and Senna occidentalis. The population, occurrence and distribution of culturable bacteria, fungi and actinomycetes in 5, 10, 15, and 20 cm depths rhizosphere samples of Musa sapientum var parasidiaca and Senna occidentalis growing in the botanical garden of the University of Lagos, Akoka, Nigeria, were investigated using standard plate count and biochemical techniques. Bacteria were the most predominant in the rhizosphere of both plants, followed by fungi, then actinomycetes. The culturable microbial population was at its maximum for depths 10 and 15 cm in M. sapientum var parasidiaca. In S. occidentalis, bacterial population was highest at 5cm, fungi at 10cm and actinomycetes at 15cm depth of the rhizosphere. Bacillus cereus had 100% distribution in the rhizosphere of both plants and Staphylococcus aureus, Pseudomonas aeruginosa, Proteus mirabilis each had 75% distribution in both rhizospheres. Rhizosphere depth of 10 cm had 100% distribution of bacteria, and the least bacterial distribution was found at 20cm. Fungi were most distributed at 15cm rhizosphere of M. sapientum var parasidiaca and at 10 and 15 cm rhizosphere of S. occidentalis. Rhizopus stolonifer had 100% distribution and the highest % occurrence in the rhizosphere of both plants with Aspergillus niger having 100 and 75% distribution in the rhizosphere of M. sapientum and S. occidentalis respectively. Actinomycetes were most distributed at 10 cm (60 and 80% in rhizosphere of M. sapientum and S. occidentalis respectively). Streptomyces sp had the highest distribution in the rhizosphere of both plants and 58.33 and 55.17% occurrences in rhizosphere of M. sapientum and S. occidentalis respectively. Streptomyces alanosinicus and S. gancidicus were absent among the rhizosphere isolates of M. sapientum. Similarly, S. globosus and S. sampsonii were not found in the rhizosphere of S. occidentalis. The abundance of the microorganisms in these rhizospheres is typical of an environment with high species richness and functional diversity.

Open Access Original Research Article

Bacteriological Screening of Water in Mangalore, India

V. C. Dhanya, J. Anitha, B. Dhanashree

Microbiology Research Journal International, Page 84-95
DOI: 10.9734/BMRJ/2013/2515

Introduction: Diarrhoea caused by contaminated water is among the most prevalent waterborne diseases in the developing countries like India. In the interest of public health, water supplies should be tested regularly to confirm their freedom from contamination.
Objective: The objectives of the study were to screen different water sources for bacterial contamination, to know the antibiotic susceptibility of the common bacterial isolates and typing of the bacterial isolates by random amplification of polymorphic DNA (RAPD) technique.
Place and Duration of the Study: Kasturba Medical College Hospital, Microbiology Laboratory, Mangalore, Karnataka, India between August 2007 and August 2009.
Methodology: Water samples (n=324) were analyzed by standard microbiological techniques for bacterial contamination. Isolates were identified biochemically and antibiotic susceptibility testing was done by disc diffusion method. Escherichia coli isolates were typed by RAPD technique.
Results: Among the water samples tested, 246 were excellent and 78 were contaminated. Contaminated samples showed the growth of commensal bacteria belonging to the family Enterobacteriaceae along with pathogens like Salmonella spp. and Vibrio spp. Many of the isolates were found to be sensitive and a few were found to be resistant to the antibiotics tested. RAPD typing showed genetic similarity and differences among the E. coli isolates from different water sources.
Conclusion: Genetic similarity among isolates of E. coli indicates a common ancestral origin or a common source. Bacterial contamination of water samples with pathogens like, Salmonella spp. and Vibrio spp. as well as the faecal coliform is a concern, as water quality is an index of health and well - being of the society. Degree of contamination observed in this study suggests a need to be vigilant to monitor water quality, in order to prevent enteric diseases.

Open Access Original Research Article

Population Dynamics and Diversity of Endophytic Bacteria Associated with Soybean (Glycine max (L) Merril)

Jitendra Dalal, Nikhilesh Kulkarni

Microbiology Research Journal International, Page 96-105
DOI: 10.9734/BMRJ/2013/2302

Aim: Endophytic bacterial population and their diversity in soybean were investigated.
Study Design: Endophytic population was assessed during different growth stages of soybean (CV JS 335) viz., vegetative and reproductive stages.
Place and Duration of Study: Microbiology Research Laboratory, Department of Microbiology, R. A. Mahavidyalaya, Washim (MS), India, during the cultivation period of June-December 2010.
Methodology: Healthy plants of soybean were screened from the different locations of Washim district (M. S., India). Samples represent each growth stage viz., vegetative (V1-V5) and reproductive (R1-R8) were collected. Population densities were expressed as log10 colony forming units (CFU) g-1 fresh weight. The isolates were identified to genus level according to Bergey’s Manual of Determinative Bacteriology on the basis morphological, cultural and biochemical characteristics.
Results: The maximum endophytic population was recorded for vegetative stage at V5 and V4 (5.74 and 5.01 log10 CFU g-1 fresh weight) and for reproductive stage at R2, R1 and R3 (5.84, 5.80 and 5.74 log10 CFU g-1 fresh weight). A total of 572 (35.50 %) from vegetative growth stages and 1039 (64.50 %) from reproductive growth stages bacterial isolates were obtained. The endophytic isolates were identified as members belonging to the genera Pseudomonas, Bacillus, Enterobacter, Klebsiella, Acetobacter Burkholderia, Rhizobium and Xanthomonas.
Conclusion: As soybean development progresses endophytic population increased. At maturity, the high population density was observed and thereafter the population declined.

Open Access Original Research Article

Cryptococcus gattii VGI and Cryptococcus neoformans VNI Associated with Wood Decay in Ficus Hollow Trees in Rio de Janeiro, Brazil

Glaucia G. Barbosa, Luciana Trilles, Bodo Wanke, Márcia dos S. Lazéra

Microbiology Research Journal International, Page 106-115
DOI: 10.9734/BMRJ/2013/2682

Aim: Considering the geographic expansion of Cryptococcus gattii, the aim of this study was to investigate hollows of living trees as a reservoir of C. gattii in Rio de Janeiro, Brazil.
Place and Duration of the Study: In an urban quarter of Rio de Janeiro city, 80 samples of decaying wood were collected. In addition, 85 decaying wood samples were collected in the wild rainforest. The samples were analyzed at the Mycology Laboratory, Evandro Chagas Clinical Research Institute, Oswaldo Cruz Foundation, from 2008-2010.
Methodology: Samples were collected by scraping the inner decaying wood of the hollows of the trunks of each tree. Pathogenic Cryptococcus species were identified by: brown colonies on niger seed agar (NSA) medium, thermotolerance at 35ºC, cycloheximide sensitivity, carbon and nitrogen assimilation tests performed by 32-Vitek System (Vitek ICB, bioMeriux, Durham, EUA). Canavanine-glycine-bromothymol blue medium (CGB) was used to determine the species of the isolates and the genotypes were determined by restriction fragment length polymorphism of URA5 gene.
Results: After plating the samples on NSA, 584 colonies were obtained from the urban quarter. C. gattii VGI was identified in 98% of colonies, followed by C. neoformans VNI 2%. The positivity of the urban area was 7.8%. The concentrations of the fungi in hollows of ficus trees ranged from 50 to 56,250 colony-forming units per gram of sample (CFU/g).
Conclusions: For the first time in Rio de Janeiro C. gattii VGI was isolated in a hollow of living tree.

Open Access Review Article

Mini-Review: Probiotics and Disease Prevention in Different Host Systems

Earl F. Bloch, Ronald D. Schultz, Willie Turner

Microbiology Research Journal International, Page 42-57
DOI: 10.9734/BMRJ/2013/1809

This review details the success of different probiotic agents to provide protection in the host from infection by pathogenic microbial agents. Probiotics are bacteria that interfere and kill pathogens but the mechanisms employed by these agents in preventing infection and disease vary from host to host. In this review the use of probiotics in evolutionary distinct hosts are discussed. The early discovery of antibiotics (such as penicillin and streptomycin) and newer generation drugs have played and continue to play vital roles in controlling infections by pathogenic agents. The extensive and indiscriminate uses of antibiotics have contributed to the survival of resistant microbial agents that cannot be controlled by conventional antibiotics. The resistant strains damage cells, tissues and organs resulting in injury and or death to the host. Probiotic agents block sites pathogenic agents need for adherence to surfaces and simultaneously activates innate and adaptive components of the immune system. The multipronged attack by probiotics are more efficient than just relying on antibiotics to disrupt cell wall structures and or poison metabolic pathways in pathogenic agents.