Advanced Journal of Microbiology Research

Advanced Journal of Microbiology Research Vol. 2015

Available online at http://internationalscholarsjournals.org/journal/ajmr

© 2015 International Scholars Journals

Full Length Research Paper

Application of methylene blue dye reduction test (MBRT) to determine growth and death rates of microorganisms

Subir Kumar Nandy and K. V. Venkatesh*

Department of Chemical Engineering, Indian Institute of Technology, Bombay, Powai, Mumbai - 400 076, India.

Accepted 29 October, 2014

Abstract

An efficacy of a compound for antimicrobial characteristics is typically evaluated through experiments to obtain the minimum inhibitory concentration (MIC). Similarly, a minimum activating concentration (MAC) can be obtained for a compound necessary for growth. We report a protocol for the determination of MIC and MAC for antibiotic and exhibition assays, respectively using methylene blue reduction test. The assay has been demonstrated on the growth of Escherichia coli on the antibiotic kanamycin, as an inhibitor, and on vitamin B12, as an activator. The slope of discoloration of methylene blue was used to determine the growth and death rates of the organism. The use of the rate constants to determine MIC/MAC values established a rational basis for determination of these relevant constants. The methodology presented here is general and can be easily adapted to other systems. The dose-response curves for extent of death / growth can be used to establish the MIC90 or MAC90 for an inhibitor or an activator, respectively. The methodology presented here rationalizes and standardizes the antibiotic and exhibition assays. The main advantage of the reported assay is the rapid and easy determination of the MIC and MAC values.

Keywords: Escherichia coli, vitamin B12, kanamycin, minimum inhibitory concentration (MIC), minimum activating concentration (MAC).

Advanced Journal of Microbiology Research Vol. 2015

Available online at http://internationalscholarsjournals.org/journal/ajmr

© 2015 International Scholars Journals

Full Length Research Paper

The impact of bacteriophages in bacteria removal associated with soba stabilisation station efficiency

Ayman Ahmed Elshayeb

Alneelain University Faculty of Science and Technology School of Biotechnology, Zip 11111, Postal code 11121 Box 12702. Khartoum – Sudan. E-mail: [email protected]. Tel: + 249122974208.

Accepted 16 October, 2014

Abstract

The existence of bacteriophages in wastewater of Soba Stabilisation Station was determined by isolating and identifying methods for their activities against Escherichia coli and Staphylococcus aureus isolated from the anaerobic, facultative and maturation ponds. The general viable count of the bacteria showed an average of 2.0 x 10⁶ cfu/ml. In broth media the affection of the bacteriophage interactions with bacteria showed increasing of bacteriophages with concomitant decrease in bacteria due to culture clearance, where the readings of the turbidity for the first and second infection showed statistical significant of light transmission among E. coli phages’ samples due to place of sample collections as follows: from the anaerobic and facultative ponds P > 0.05, facultative and maturation P < 0.05 and anaerobic and maturation P > 0.05. Whilst, the S. aureus phages samples’ light transmission from the anaerobic and facultative P < 0.05, facultative and maturation P < 0.05 and anaerobic and maturation P > 0.05. On solid media, the affection of the bacteriophage was recognised by the phage plaque formation on bacterial cultures. The linear equations of phages’ densities and distributions according to their wavelength were y = 0.0008x + 0.0303 for E. coli phage and y = -0.0102x + 0.2438 for S. aureus phage. This study concluded that phages naturally present where their hosts present and naturally destroyed bacteria that aided to recover from polluted environment.

Key words: Bacteriophage, Escherichia coli/ general viable count, light transmission, linear equations, stabilisation station, Staphylococcus aureus.

Advanced Journal of Microbiology Research Vol. 2015

Available online at http://internationalscholarsjournals.org/journal/ajmr

© 2015 International Scholars Journals

Full Length Research Paper

Microbiological quality of packaged drinking water brands marketed in Ibadan metropolis and Ile-Ife city in South Western Nigeri

O. Oyedeji*, P. O. Olutiola and M. A. Moninuola

Department of Microbiology, Obafemi Awolowo University, Ile-Ife, Nigeria.

Accepted 5 November, 2014

Abstract

Continuous increase in the sale and indiscriminate consumption of packaged drinking waters in Nigeria is of public health significance. One hundred and eight samples comprising 16 bottled and 20 sachet water brands purchased randomly all over Ibadan and Ile-Ife cities in South Western Nigeria were analysed for presence of bacterial indicators of water quality. Total heterotrophic bacteria plate counts (HPC) ranged from 2 to 150 for bottled water and 5 to 200 for sachet water brands. One brand of bottled water and eight brands of sachet water had mean HPC greater than 100 per ml millilitre water and thus fell below the United States Environmental Protection Agency (USEPA) and World Health Organisation (WHO) drinking water standard of 100 HPC per millilitre water. Total coliforms and Escherichia coli were detected in only one brand of bottled water. All brands of sachet water (100%) had total coliforms, four brands (20%) had presence of E. coli while Enterococcus faecalis was recovered from two (10%) of the brands. Most of the sachet water brands fell below WHO drinking water standards and are therefore of doubtful quality. Efforts need to be intensified in the monitoring of activities in this rapidly expanding industry with a view to raising standards.

Key words: Bottled water, sachet water, microbiological quality, drinking water, South Western Nigeria.

Advanced Journal of Microbiology Research Vol. 2015

Available online at http://internationalscholarsjournals.org/journal/ajmr

© 2015 International Scholars Journals

Full Length Research Paper

Effect of processing on functional properties of Spirulina protein preparations

Amita Mahajan¹*, Neetu² and A. S. Ahluwalia²

¹Rayat and Bahra Istitute of Engineering and Biotechnology, Kharar, Punjab, India.

²Department of Botany, Panjab University Chandigarh-160014, India.

Accepted 19 August, 2014

Abstract 

The present investigation has been undertaken selecting a protein rich blue green alga Spirulina platensis in relation to change in functional properties of its proteins on chemical treatment with succinic anhydride, acetic anhydride and formaldehyde for succinylation, acetylation and methylation respectively. Modified proteins have been studied for their functional properties such as protein solubility, foaming properties; emulsification properties and viscosity. Protein solubility in unmodified water soluble Spirulina protein fraction was found to be 23%. It decreased considerably on treatment with all the three modifying reagents. Emulsification activity (EA) increased slightly on methylation, whereas succinylation and acetylation resulted in a decreased EA and emulsion stability (ES). Foam capacity (FC) increased on treatment with succinic anhydride at all the concentrations used, whereas acetylation and methylation could show an increase in FC only at lower concentrations. FC was found to be maximum on succinylation and minimum on acetylation. Foam Stability (FS) was found to be much higher with methylation and acetylation. The protein fraction modified with succinic anhydride has shown the maximum viscosity followed by acetylation. Methylation however, caused a rapid decrease in viscosity and it was more pronounced at lower concentrations.

Key words: Acetylation, functional properties, methylation, proteins, Spirulina platensis, succinylation.

Advanced Journal of Microbiology Research Vol. 2015

Available online at http://internationalscholarsjournals.org/journal/ajmr

© 2015 International Scholars Journals

Full Length Research Paper

A changing pattern in antimicrobial susceptibility of Salmonella enterica serotype isolated In North India

Deepak Arora¹, Rakendra Singh^2*, Manjot Kaur¹ and Rajinder S. Ahi¹

¹Department of Microbiology, Adesh Institute of Medical Sciences and Research, Bhatinda, Punjab, India-151001.

²Department of Internal Medicine Adesh Institute of Medical Sciences and Research, Bhatinda, Punjab, India-151001.

Accepted 5 November, 2014

Abstract

Typhoid fever continues to remain a health problem as the causative organism Salmonella typhi has developed resistance to many of the antibiotics used. This study was undertaken to determine the current pattern of resistance to antimicrobial agents of S. typhi isolates obtained in a tertiary Health care Hospital. 309 samples were taken. Sensitivity to ampicillin, chloramphenicol, cotrimoxazole, ciprofloxacin and ceftriaxone was determined by disc diffusion, and the minimum inhibitory concentration (MIC) was determined. Antibiotic sensitivity was carried out by Kirby-Bauer method. ESBL screening and phenotype confirmation were done following National Committee for Clinical Laboratory Standards (NCCLS) recommendations for Escherichia coli. Isolation rates of Salmonella typhi was prominent in 2002 - 2003 and have remained stable. S. paratyphi-A is showing an increasing trend. The 3 common antibiotics which were showing resistance earlier are now showing sensitivity. The study indicates that MDR S. typhi is on the rise. There is also re-emergence of chloramphenicol sensitivity. Sensitivity pattern of causative organism must be sought before instituting appropriate therapy to prevent further emergence of drug resistance. Indiscriminate use of ciprofloxacin or ceftriaxone should be strongly discouraged. They should be used as second line agents. Also, the treatment must not be completely dependent on the Widal test. Blood culture and clinical history must be taken into consideration for treatment.

Key words: Ciprofloxacin, ceftriaxone, Enteric fever, multi-drug resistant (MDR) Salmonella, Minimum inhibitory concentration (MIC).

Advanced Journal of Microbiology Research Vol. 2015

Available online at http://internationalscholarsjournals.org/journal/ajmr

© 2015 International Scholars Journals

Full Length Research Paper

Association of IGF- 1 gene polymorphism with milk production traits and paternal genetic trends in Iranian Holstein bulls

Yousef Mehmannavaz¹*, Cyrus Amirinia², Mortaza Bonyadi³ and Rasoul Vaez Torshizi⁴

¹Department of Animal Science, Faculty of Agriculture, Science and Research Branch, Islamic Azad University, Tehran, Iran.

²Department of Animal Biotechnology, Animal Science Research Institute of Iran, Karaj, Iran.

³Center of Excellence for Biodiversity, University of Tabriz, Tabriz, Iran.

⁴Animal Science Department, Faculty of Agricultural, Tarbiat Modares University, Tehran, Iran.

Accepted 12 November, 2014

Abstract

The effects of Insulin-Like Growth Factor-1 polymorphism were examined on milk production traits and genetic trends in the Iranian Holstein bulls. A total of 282 bulls were genotyped for SnaBI restriction site in the 5' flanking region of IGF-1 by applying PCR-RFLP method. The allele frequencies for C and T alleles were 0.562 and 0.438, respectively. The results indicated that genetic variants at the 5'-noncoding region of the bovine IGF-1 gene had a marked effect on estimated breeding values of milk (EBVM) and fat yields (EBVF). The heterozygous bulls (CT genotype) had higher EBVM and EBVF than homozygous bulls (P < 0.1) . The average substitution effects of alleles were not significant for none of studied traits (P > 0.1). The studied polymorphism of IGF-1 showed no significant association with genetic trends of milk related traits (P > 0.1). These results suggest that allelic interaction in IGF-1 polymorphism as over dominance and might be effectiveness in animal improving by crossbreeding.

Key words: IGF-1, polymorphism, Holstein, genetic trend.