MOSP - Macao Scientific Publishers

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Assessment of the temporal change in groundwater quality when stored at different temperatures in household conditions, in the equatorial region of Central Africa

Moïse Nola*, Ernest Djarmaila, Norbert Kemka, Serge H. Zébazé Togouet, Nour-Eddine Chihib, François Krier, Pierre Servais, Jean-Pierre Hornez and Thomas Njiné

Abstract: The study carried out aimed at assessing the impact of groundwater storage temperature at household conditions on the temporal evolution of electrical conductivity and the future of heterotrophic aerobe bacteria (HAB). The storage duration was 7 days and the considered temperatures were 3, 10, 18 and 25°C. The electrical conductivity during storage reached 829 µS/cm at 3 - 18°C and 850 µS/cm at 25°C. The maximum HAB abundance was 9 x 103 cfu/ml at 3°C, 41 x 103 cfu/ml at 10°C, 44 x 103 cfu/ml at 18°C and 93 x 103 cfu/ml at 25°C. At the 3rd and 7th days storage at 3°C, changes in bacterial abundances values were significantly in the same direction as those of electrical conductivity (P < 0.05). The highest cell apparent growth rate at the 3rd day storage was 0.249 d-1 at 3°C, 0.559 d-1 at 10°C, 0.924 d-1 at 18°C and 1.233 d-1 at 25°C. However, at the 7th day storage, it was 0.362 d-1 at 3°C, 0.497 d-1 at 10°C, 0.690 d-1 at 18°C and 0.672 d-1 at 25°C. At the 3rd day storage, a decrease in cell abundance was noted in 90% of samples at 3°C and the cell apparent inhibitory rate varied from 0.012 to 0.989 d-1. The storage of groundwater in households’ conditions for a long period would alter its bacteriological quality.[...] Read More.

Keywords: Bacterial abundance’s evolution, electrical conductivity, groundwater, storage temperature, duration.

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Inhibitory activity of Paenibacillus macerans and Paenibacillus polymyxa against Ralstonia solanacearum

Bin Li*, Ting Su, Rongrong Yu, Zhongyun Tao, Zhiyi Wu, Soad A. E. Algam, Guanlin Xie, Yanli Wang and Guochang Sun

Abstract: The inhibitory activities of seven Paenibacillus polymyxa strains and nine Paenibacillus macerans strains against Ralstonia solanacearum strains were examined. Result from this study indicated that the growth of all R. solanacearum strains except strain E406 were inhibited by P. macerans MB02-992 and P. polymyxa MB02-1007, while the other fourteen Paenibacillus strains had no in vitro inhibitory effect against R. solanacearum strains. In addition, suspensions of the two antagonistic bacteria showed antibacterial activities against R. solanacearum under different treatments and reduced the disease incidence and severity of tomato bacterial wilt. Overall, this study clearly demonstrates that antagonistic substances may play an important role in biocontrol of the two antagonistic bacteria. However, antimicrobial activities of P. macerans and P. polymyxa depend on the Paenibacillus strains and the target pathogen. This is the first report about the antibacterial activities of Paenibacillus strains against R. solanacearum strains isolated from different host plants.[...] Read More.

Keywords: Paenibacillus, antagonistism, biovar, Ralstonia solanacearum, tomato wilt.

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A microbiologic evaluation of patients with chronic prostatitis and relation with clinical symptoms

Fahriye Eksi*, Ahmet Erbagci, Sakip Erturhan, Iclal Balci, Mehmet Solakhan and Faruk Yagci

Abstract: In this study urine and prostatic secretion samples of patients with chronic prostatitis were investigated for various prostatitis pathogens and the correlation between clinical symptoms. A total of 60 patients with chronic prostatitis were examined, prostatic secretion and urine specimens were evaluated under direct microscopy after staining with Giemsa and Gram. The selective media were used to investigate the presence of bacterial pathogens, Mycoplasma hominis and Ureaplasma urealyticum. Based on the laboratory findings of patients, 11(18.3%) were found to have chronic bacterial prostatitis, 49 (81.7%) were found to have chronic pelvic pain syndrome. Organisms isolated in patients with chronic bacterial prostatitis included Escherichia coli in four cases, Staphylococcus aureus in two cases and Pseudomonas aeruginosa, Klebsiella pneumoniae, coagulase- negative staphylococci, Enterococcus faecalis and diphtheroids in one case each. Of the 49 patients with chronic pelvic pain syndrome, U. urealyticum was isolated in seven and M. hominis in one of the patients. Premature ejaculation was more frequently detected in the patient group with chronic bacterial prostatitis than the patient group with chronic pelvic pain syndrome. Analysis of etiology of chronic prostatitis in our patients showed that U.urealyticum and E. coli were common pathogens of chronic prostatitis. We concluded that chronic bacterial prostatitis may increase the risk of premature ejaculation.[...] Read More.

Keywords: Chronic prostatitis, etiology, Ureaplasm urealyticum, Mycoplasma hominis, premature ejaculation.

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Antioxidant and antimicrobial activities of Turkish endemic Achillea species

Ismail Turkoglu, Semra Turkoglu*, Sait Celik and Mustafa Kahyaoglu

Abstract: This study was undertaken to examine in vitro antioxidant, radical scavenging and antimicrobial activities of extracts of Achillea schischkinii Sosn. and Achillea teretifolia Waldst. and Kitt (Asteraceae). The plant materials were extracted in methanol, water and chloroform using rotary evaporator apparatus. The extracts were screened for antioxidant activity using the ABTS radical scavenging capacity, DPPH radical scavenging capacity, superoxide anion radical scavenging, hydrogen peroxide scavenging and metal chelating activities and compared to standard antioxidants. The results obtained in this study indicate that A. schischkinii and A. teretifolia are potential sources of natural antioxidants, antimicrobial activity screening was performed by the disc diffusion method against 6 bacteria strains and 2 yeast species. A. teretifolia displayed strong inhibitory effects against Pseudomonas aeruginosa. The A. teretifolia extract also showed antimicrobial activity against Saccharomyces cerevisae. I contrast, the A. schischkinii extract showed no antimicrobial activity against gram-positive and gram-negative bacteria nor against yeast.[...] Read More.

Keywords: Achillea schischkinii, Achillea teretifolia, antioxidant, antimicrobial.

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Detection of deep fungal infection in SLE patients with multiplex fluorescent real-time PCR

Ledong Sun, Caimei Zhong, Mingyu Chen, Bing Wang, Xueyan Liu, Xiufen Zheng, Fengjiao He, Zaigao Zhou and Kang Zeng*

Abstract: To establish a rapid, sensitive and specific detection method for deep fungal infection, we detected the deep infection of Candida albicans and Aspergillus flavus in patients with systemic lupus erythematosus by using multiplex fluorescent real-time PCR (MFRT-PCR). Firstly, the positive rate, sensitivity and specificity of multiplex fluorescent quantitative PCR for detecting the fungal infection was tested in 20 specimens from systemic lupus erythematosus patients with C. albicans and A. flavus infections. Then, 20 specimens from SLE patients with suspected deep fungal infections and 20 other microorganism infections were detected with MFRT-PCR. Results showed the positivity rate and specificity of both 100% for detecting the deep C. albicans and A. flavus infection. Its detecting sensitivity for deep fungal infection was 75%, which was significantly higher than that of fugal culture method (40%) (P < 0.05). MFRT-PCR is a better method for detecting deep C. albicans and A. flavus infections, with higher sensitivity and specificity than fungal culture.[...] Read More.

Keywords: Systemic lupus erythematosus, deep fungal infection, multiplex fluorescent quantitative PCR.

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In vitro characterization of bacteriocin producing Bacillus subtilis from milk samples

S. Hemalatha* and S. Shanthi

Abstract: Bacillus subtilis was isolated from milk samples. Antibiotic resistance and the antimicrobial activity of B. subtilis were studied. All the four isolates of B. subtilis were sensitive to antibiotics such as streptomycin (25 g/ml), ampicillin (10 g/ml), penicillin (10 g/ml), erythromycin (15 g/ml), amoxycillin (10 g/ml).But they were resistant to bacitracin (10 g/ml). B. subtilis shown antibacterial activity against the selected human pathogens such as Salmonella spp, Streptococcus spp, Klebsiella spp and E. coli. The antimicrobial substance from B. subtilis extracted with organic solvent such as ethyl actetate have also shown antibacterial activity against the human pathogens. The proteineceaous nature of the B. subtilis exerted antimicrobial activity. The amount of protein varied between 0.05 - 0.55 mg/ml and the protein was qualitatively analyzed by SDS-PAGE. The entire samples have shown peptide < 62 kDa.[...] Read More.

Keywords: Bacillus subtilis, antibiotics, Salmonella spp, human pathogens, ethyl acetate, SDS PAGE.

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Seroepidemiological survey of canine Visceral leishemanisis in Sarab District, East Azerbaijan Province, Northwest of Iran in 2009

M. Khanmohammadi*, E. Fallah, S. Rahbari, I. Sohrabi, M. Farshchian, F. Hamzavi and A. Mohammadpour Asl

Abstract: Visceral leishmaniasis (VL) is one of the most important endemic parasitic diseases in different parts of Iran. It is also a health problem in some tropical and subtropical countries. The purpose of the present study was to determine the seroprevalence of canine VL (CVL) in owned dogs of Sarab and to identify the isolated Leishmania species. Sera samples were taken from 384 dogs from 30 random villages around Sarab and tested by enzyme-linked immunosorbent assay (ELISA) . A total of thirty five dogs were seropositive. The seroprevalence rate (SPR) of CVL was 9.1% (95 % CI; 6.6 - 12.4). Out of 361 (94%) asymptomatic dogs, 31 (8.6%) were seropositive, and out of 23 (6%) symptomatic dogs, 4 (17.4%) were seropositive. 306 (79.7%) dogs were male and 78 (20.3%) were female. 28 (9.2%) male dogs and 7 (9%) female dogs were seropositive. There was no statistically significant relation between sex and seroprevalence (p = 0.962). The largest age group was 2 - 4 years, with 170 (44.3%) dogs out of which only 18 dogs (10.5%) were seropositive. Agreement between the ELISA test and clinical signs was 86.7%. A significant difference in the presence of antibodies against Leishmania was seen between symptomatic and asymptomatic dogs (p = 0.015) . ELISA was efficiently sensitive in the identification of infected dogs and seems to be an appropriate tool in rapid diagnostic screenings. ELISA is highly recommended to be applied as a standard test for routine CVL diagnosis.[...] Read More.

Keywords: Dogs, enzyme-linked immunosorbent assay (ELISA), epidemiology, Iran, Visceral leishmaniasis, prevalence, serology.

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Influence of cultural conditions on hydrogen peroxide production by lactic acid bacteria isolated from some Nigerian traditional fermented foods

I. A. Adesokan*, Y. A. Ekanola and B. M. Okanlawon

Abstract: In this study, influence of cultural conditions on hydrogen peroxide production by lactic acid bacteria was investigated. Leuconostoc mesenteroides produced the highest quantity (0.024 L) of hydrogen peroxide while Lactobacillus plantarum produced the lowest amount (0.016 g/L) in normal MRS. The effect of temperature on hydrogen peroxide production was determined and the result showed that Leuc. mesenteroides produced the highest quantity (0.024 g/L) at 30°C while L. brevis produced the lowest amount (0.012 g/L) of hydrogen peroxide at 45°C. Leuc. mesenteroides produced the highest amount of hydrogen peroxide (0.032 g/L) when mannitol was used as the carbon source while Lactobacillus delbrueckii and Lactobacillus fermentum produced the lowest amount (0.020 g/L) when glucose was used as the carbon source. Furthermore, Leuc. mesenteroides produced the highest amount of hydrogen peroxide (0.033 g/L) when potassium nitrate was used as the nitrogen source while L. fermentum and L. delbrueckii produced the lowest amount (0.020 g/L) when yeast extract was used as the nitrogen source. Hydrogen peroxide produced by Leuc. mesenteroides has the highest zone of inhibition against Pseudomonas aeruginosa while hydrogen peroxide produced by L. plantarum had the lowest zone of inhibition against Staphylococcus aureus.[...] Read More.

Keywords: Hydrogen peroxide production, lactic acid bacteria, temperature.

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Acetoin production associated with the increase of cell biomass in Bacillus pumilus ATCC 14884

Zijun Xiao*, Shuling Qiao, Cuiqing Ma and Ping Xu

Abstract: Some of Bacillus strains, especially Bacillus pumilus, were the best acetoin producers. This study attempts to disclose the mechanisms of vigorous acetoin excretion using B. pumilus ATCC 14884 as a model strain. The production of acetoin by this strain has been studied under a variety of conditions. Glucose was found to be a much better substrate than citrate, pyruvate, succinate, or fumarate for acetoin production. Malonate was used to slow down the Krebs cycle and the addition of 0.10 M malonate was found to inhibit cell growth slightly, but reduce the production of acetoin by 13%. The addition of 100 g/L NaCl strongly reduced cell growth and acetoin formation. On the other hand, 200 g/L glucose reduced the rate of cell growth, but led to the largest final acetoin production of all the conditions studied. Linear relationships between acetoin accumulation and cell biomass, which increased in the lag and arithmetic growth phases were found when glucose was used as the carbon source, which corroborated acetoin as a primary metabolite. Metabolite study indicated that there were few minor pathways for by-products. Acetoin was utilized as a preferential carbon source without the catabolite repression of glucose, suggesting that the main physiological function of acetoin excretion is an energy-storing strategy in this species.[...] Read More.

Keywords: Acetoin, biomass, association, metabolism, Bacillus pumilus.

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Investigating the effects of various additives on surface activity and emulsification index of biosurfactant resulting from broth media of Bacillus subtilis PTCC 1023

Full Length Research Paper

Abstract: Surfactants are amphipathic molecules which reduce surface tension and are widely used in pharmaceutical, cosmetic and food industries. In the present study, the production of biosurfactant by Bacillus subtilis PTCC 1023 was studied. B. subtilis was grown in the nutrient broth medium and biosurfactant production was evaluated by measuring the surface tension and emulsification index (E24) each 24 h. The bacterium’s biosurfactant production was investigated in different status with variable factors such as incubation time, temperature, aeration rate and presence of several additives. Then the best fermentation condition was investigated for maximum biosurfactant production and finally biosurfactant identity was investigated using some chemical and spectroscopy methods. The maximum biosurfactant production by B. subtilis PTCC 1023 was obtained when it was grown in brain-heart broth medium containing FeSO4 (4×10-3 M), MnSO4 (1.3×10-3 M), starch (4%) and castor oil (4%) which incubated in a 300 rpm rotary shaker at 30°C for 24 h. Lipopepetide natures in this biosurfactant was confirmed by biochemical and spectroscopic methods.[...] Read More.

Keywords: Bacillus subtilis, biosurfactant, emulsification index, surface tension.

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