Open Access Original Research Article

Sero-prevalence of Japanese Encephalitis (JE) among Nepalese Children

Sital Khanal, Shamshul Ansari, Shital Raj Basnyat, Devraj Joshi, Nabaraj Adhikari, Upendra Thapa Shrestha, Dhiraj Acharya, Pramila Adhikari, Prakash Mani Niraula, Rama khadka, Bishnu Prasad Upadhyay

Microbiology Research Journal International, Page 126-134
DOI: 10.9734/BMRJ/2015/15442

Background: Japanese encephalitis (JE) is one of the major public health problems particularly in the Terai regions of Nepal. Childrens upto the age of 15 years are more susceptible for JE. The present study was conducted to aim the sero-prevalence of JE among children of Nepal.
Methods: The samples were collected and processed at National Public Health Laboratory (NPHL). In this study, children of age upto 15 years defined with Acute Encephalitis Syndrome (AES) were studied. A total 1009 samples, were collected and tested by MAC ELISA technique for the detection of Anti JEV-IgM.
Results: From the processed samples, 107 (10.61%) were found positive for Anti JEV-IgM. Among total JE seropositive cases, 58 (54.21%) were male and 49 (45.79%) were female and found no significant difference in distribution of disease among gender (χ²=1.03, P>0.05). The majority of seropositive cases (40.18%) were found in the children of 6 to 10 years of age. The highest number of seropositive cases (34, 29.31%) were detected from Mid Western Development Region (MWDR) followed by Far Western Development Region (25%). Analyzing month wise seasonal variation, the sero-positivity rate was highest in the month of August (28.89%) followed by September (18.37%) and no positive cases were found in the month of March.
Conclusions: In conclusion, the higher prevalence of JE among Nepalese children indicates alarming seasonal endemicity of the disease.

Open Access Original Research Article

Invertase Production by Irradiated Aspergillus niger OSH5 Using Agricultural Wastes as Carbon Source

Ola E. A. Al-Hagar, A. S. Ahmed, I. A. Hassan

Microbiology Research Journal International, Page 135-146
DOI: 10.9734/BMRJ/2015/11539

Aim: The objective of this study was to isolate microbial species having the ability for production of invertase enzyme and to study some optimal culture conditions for maximum invertase production by an isolate of Aspergillus niger OSH5 which showed the highest invertase activity among the screened isolates. The enhancement effect of gamma irradiation on invertase activity was also investigated.
Place and Duration of Study: Plant Research Department, Nuclear Research Center, Atomic Energy Authority, Cairo, Egypt, between July, 2013 and January, 2014.
Methodology: Seven microbial isolates were screened for invertase production. The most active isolate Aspergillus niger OSH5 was subjected to gamma irradiation mutagenesis to enhance invertase production. The optimal culture conditions including shaking speeds, temperature, incubation period, and pH were tested for maximum invertase production. Moreover, production of invertase using solid-state fermentation was also studied.
Results: Among the seven isolates, A. niger OSH5 was found the most active on invertase production. The most effective carbon source in intracellular invertase production (14.8±1.27 u/ml) was sucrose at a concentration of 3% (w/v) using shaking speed of 150 rpm at 25ºC and pH 6.5 after incubation for 6 days. Among the screened agro-industrial wastes that were used as solid substrates for invertase production, wheat bran at a concentration of 14% (w/v) was the most conductive substrate for extracellular invertase production (15.9±2.44 u/g).
Conclusion: The obtained results indicate the efficient use of low cost fermentation for invertase production by an A. niger isolate. Moreover, these findings indicate the efficient use of gamma irradiation as a tool for invertase production enhancement.

Open Access Original Research Article

Antimicrobial Effect of Lime Juice Treatment on the Shelf-Life of Zobo Drink

O. R. Ezeigbo, M. U. Ekaiko, N. G. Agomo, K. Ojukwu, A. I. Nnadozie

Microbiology Research Journal International, Page 147-153
DOI: 10.9734/BMRJ/2015/15534

Zobo drink is an indigenous non-alcoholic drink made from hot water roselle calyces of Hibiscus sabdariffa. The drink has gained wide acceptance, as it is consumed by several millions of people from different socio-economic classes and background in West African sub-region. The greatest limitation for large-scale production of zobo drinks is the rapid deterioration of the drink. Its shelf-life is approximately 24 hours after production, if not refrigerated. The effect of lime juice on the microorganisms associated with zobo drink was investigated. Zobo drink was prepared by maintaining the appropriate hygienic standards. Microbiological analysis was carried out on the prepared sample, before treatment with lime juice, to determine its effect on the microbial quality of the drink. The mean total coliform count from the prepared sample was 0.1 x 10-4 cfu/mL, aerobic bacterial count was 0.2 x10-4 cfu/mL and the fungal count was 0.4 x 10-4 cfu/mL. Microorganisms isolated from the prepared sample include Staphylococcus spp, Lactobacillus spp, Bacillus spp and Penicillium spp. The antimicrobial effect of the lime juice on the different isolates showed significant zone of inhibition even at 6.25% concentration. The total coliform and aerobic bacterial count generally decreased in value and showed no growth at 50-100% concentrations of lime juice for 3 days and 75-100% concentrations for 5 days. The findings from this study showed that lime juice can be used as natural preservative to prolong the shelf- life of zobo drink for a period 5 days under normal room temperature.

Open Access Original Research Article

Application of Response Surface Methodology for the Optimization of Growth of Pearl Millet

P. Sunitha, K. Aruna Lakshmi, K. V. Narayana Saibaba

Microbiology Research Journal International, Page 154-166
DOI: 10.9734/BMRJ/2015/14821

A Group of mathematical and statistical designs collectively known as Response Surface Methodology (RSM) are increasingly being used to optimize a product or process. The present study attempts to evaluate the efficacy of the mathematical model Central Composite Design (CCD) and RSM in optimizing parameters for enhancing plant growth of Pearl millet (Pennisetum glaucum). The interactions between different levels of Nitrogen (0,6,12,24,36,48 kg/acre) and Azotobacter (0, 5, 10, 20, 30, 40 mg of the recommended dose per gram seed) was theoretically optimized and later experimentally verified in the field during Kharif season of 2009-2011. Results revealed that all treatments enhanced plant growth by increasing root length, root weight, shoot length and shoot weight over control. Best growth of Pearl millet was obtained when optimum combination of 17.75 kgs/acre Nitrogen (75% of the recommended dose of fertilizer) and 6.82 mg of Azotobacter was used. This combination enhanced growth by 3 to 6 fold compared to control. The predicted optimum values of root and shoot length were 17.69 cm and 163.76 cm fairly agree with the experimental optimum values of 18.2 cm and 164.8 cm respectively. Our study proved that RSM could be used effectively to optimize growth of Pennisetum and the CCD is efficient, simple, economical, time saving and can be adopted for optimizing crop yields.

Open Access Original Research Article

Detection of Multi-drug Resistant Non-typhoid Salmonella Isolates in Cases of Gastroenteritis in Egypt

Mahmoud Shokry Mahmoud, Mona Abdel Monem Esmail, Rasha M. M. Khairy, Omnia S. Mazher

Microbiology Research Journal International, Page 167-174
DOI: 10.9734/BMRJ/2015/14322

Aims: The current study aimed to determine the prevalence and multidrug resistance of non-typhoid Salmonella in patients with gastroenteritis at Minia, Egypt. The presence of tetB gene and cat gene was determined by PCR to have a clue of the resistance mechanisms to tetracycline and chloramphenicol as available and cheap drugs in treatment of non-typhoid Salmonella infections in developing countries.
Methodology: Five hundred stool samples were collected from patients with gastroenteritis, attending Minia Fever Hospital, Egypt, in the period from August 2011 to January 2014, all the participants showed negative- Widal test that was necessary to be included in the study. The stool samples were examined by standard microbiological, biochemical, invA gene amplification by PCR and serological tests to isolate non-typhoid Salmonella. The antimicrobial susceptibility was tested by the disc diffusion method using a panel of 11 discs of different antimicrobial groups, the Production of extended-spectrum β-lactamase was detected using the double disk synergy test. The presence of tetB gene and cat gene was determined by PCR in tetracycline and chloramphenicol resistant isolates respectively.
Results: Of 500 samples, 4.4% (22/500) were non-typhoid Salmonella. Most of isolates were resistant to; ampicillin 86.4% (19/22) then tetracycline and trimethoprim-sulphamethoxazole 77.3% each (17/22), 27.3% of isolates (6/22) were resistance to chloramphenicol. However low percentage of isolates were resistant to quinolones and most of isolates (95.5%) were sensitive to amikacin and ciprofloxacin. 18% (4/22) of isolates were ESBL producers and 81.8% (18/22) were multiple drug resistant (MDR). tetB and cat genes were detected in 64.7% (11/17) and 50% (3/6) of isolates resistant to tetracycline and chloramphenicol respectively.
Conclusion: This study revealed high prevalence of MDR non-typhoid Salmonella isolates that represents a serious health problem in the region under study. Quinolones remain the treatment of choice, while amikacin can be used in children. Continuous search for the mechanisms of resistance by molecular studies is important for effective management of NTS infections in Egypt.

Open Access Original Research Article

Petroleum Degrading Potentials of Bacterial Isolates from River Ethiope, Delta State, Nigeria

Idise Okiemute Emmanuel, Owhe-Ureghe Ubreye Benjamin

Microbiology Research Journal International, Page 175-184
DOI: 10.9734/BMRJ/2015/8111

Water samples were collected from twelve locations along the Ethiope River, Delta State, Nigeria to determine the petroleum degrading potentials of bacterial isolates and their x-ray mutants using standard methods. Bacteria isolated were Bacillus sp, Klesiella sp, Escherichia sp, Micrococcus sp, Pseudomonas sp, Staphylococcus sp and Streptococcus sp. All the isolates and their x-ray mutants possessed ability to degrade 1% (v/v) Forcados crude-oil with Bacillus sp, Escherichia sp and Pseudomonas sp isolated from a location, with reported crude-oil spillage, degrading 2.5% (v/v). X-ray mutation led to % kill that ranged from 3.58 (Micrococcus sp) to 11.59 (Streptococcus sp). There were reduction in crude-oil degradation in mutants from 0.33% (Escherichia sp) to 6.31% (Pseudomonas sp) with parent Pseudomonas sp (1.680 ppm) and mutant Streptococcus sp (1.474 ppm) being highest and least degraders respectively. Statistically significant differences (t= 0.95) in crude-oil degradation were observed for parents and mutants of Streptococcus sp, Escherichia sp and klebsiella sp but not for Bacillus sp, Staphylococcus sp, Pseudomonas sp and Micrococcus sp. Thus, irrespective of source of isolation on the Ethiope River, crude-oil degrading bacteria abound with increased ability on exposure to crude-oil pollution and reduced ability on x-ray mutation. The bacteria encountered in this study could be employed in bioremediation of crude-oil polluted environments.