Open Access Short Research Article

Microbial Safety of Street Vended Fruit Juices in Dhaka City of Bangladesh

Muhammad Ekhlas Uddin, Tanzina Akter, Md. Anowar Khasru Parvez, Shamsun Nahar, Safirun Pervin, Bishajit Debnath, Suvamoy Datta

Journal of Advances in Microbiology, Page 1-7
DOI: 10.9734/JAMB/2017/33651

Freshly squeezed fruit juice is a nutritious drink. Its appealing look and attractive taste make it a popular drink among many different aged people. But the risk due to fresh juice consumption is very important.

Aims: The present study was undertaken to investigate the microbiological quality of freshly squeezed juices and to determine their safety for human consumption.

Place and Duration of Study: This study was conducted in Microbiology Department of Primeasia University, Banani, Dhaka-1213, Bangladesh during February, 2015 to April, 2015.

Methodology: Four types of fruit juices such as Lemon, Sugarcane, Mango, and Papaya juice were collected from Banani, Tejgaon, Mirpur, Badda and Uttara. Total viable bacteria and fungi counts were estimated by using nutrient agar (NA) and Sabouraud’s dextrose agar plates respectively. Pathogenic bacteria were isolated and identified using selective media and various biochemical tests. Kirby-Bauer disc diffusion method on Mueller Hinton agar media was used for the determination of sensitivity of the isolated strains to commonly prescribed antibiotics.

Results: Among all the samples, Lemon juice from Uttara, Sugarcane juice from Mirpur and Uttara and Papaya juice from Tejgaon were of poor quality due to having all five types of pathogenic proliferation of bacteria including Escherichia coli, Klebsiella spp, Staphylococcus spp, Vibrio spp, and Salmonella spp. Ampicillin was found to be the least effective antibiotics against the isolates whereas Nalidixic acid was highly sensitive against klebsiella spp.

Conclusion: The result revealed that most of the samples had high microbial load, and were not suitable for consumption.


Open Access Original Research Article

Chemical Mutagenesis of Bacillus subtilis for Improved Mannanase Biosynthesis

B. S. Adeleke, S. O. Ojo, Y. D. Oluwafemi, O. O. Olaniyi

Journal of Advances in Microbiology, Page 1-6
DOI: 10.9734/JAMB/2017/30911

The aim of the present study was to isolate bacterial associated with abattoir waste water, compost saw dust, soil and water samples from Ilaje Lake, Ondo State, Nigeria. The microbial isolates were identified using standard microbiological method. The bacterial isolates were screened for mannanase production. Mannanase activity was determined by dinitrosalicylic acid (DNSA) method while protein concentration in the fermentation broth was quantified by Lowry’s method. Isolate designated 2k tentatively identified as Bacillus subtilis had the highest mannanase activity.                The isolate with highest mannolytic activity was then subjected to different mutagens. The mutants of Bacillus subtilis generated were screened for mannanase production in comparison with the         wild type in submerged state fermentation. All the mutant strains generated from B. subtilis            had their mannolytic activities repressed in comparison with the wild strain. Out of mutants screened, mutant designated CH017 have the highest mannolytic activity 1.20 U/mg. The mannanase activity produced by CH017 was approximately 44% lower than the wild strain. The pretreatment of B. subtilis with nitrous acid caused enzyme repression. Therefore, another chemical mutagen should be worked upon whether it would result in appreciable yield of mannanase.


Open Access Original Research Article

Evaluation of Antagonistic Potential of Soil Bacteria against Plant Pathogenic Fungus: Aspergillus niger

A. P. Rao, B. E. Agbo, N. S. Udoekong, H. A. Etuk

Journal of Advances in Microbiology, Page 1-7
DOI: 10.9734/JAMB/2017/33320

Soil bacteria are able to synthesize a wide range of metabolites with fungicidal activity. Nine bacterial isolates were obtained from the botanical garden of university of Calabar. Preliminary examination of isolates was carried out using morphological characteristics and Gram’s reaction. These isolates were designated with codes SB1, SB2, SB3, SB4, SB5, SB6, SB7, and SB8. Bacterial isolates were evaluated for their potential of antagonism against Aspergillus niger isolated from spoiled vegetables like tomatoes by using agar diffusion technique. Percentage inhibition of mycelial growth by these isolates recorded values as 27%, 0%, 66%, 40%, 97%, 0% and 23% respectively. Isolates were analyzed through several biochemical tests and were identified as Bacillus sp., Enterobacter spp., Pseudomonas spp., Proteus spp., Escherichia coli, Streptococcus spp. and Staphylococcus spp. respectively. These result indicated that bacterial species exhibited varying degree of antagonism against the fungus Aspergillus niger. Escherichia coli showed maximum inhibitory potential against tested fungus with reduction of up to 97% in their fungal growth. Pseudomonas spp. and Bacillus spp. followed with 66.7%. This result showed that Pseudomonas spp. and Bacillus spp. exhibited similar percentage of antagonism against Aspergillus niger. From the results obtained, it can be interpreted that test bacterial species can be used as fungal agents like Aspergillus niger.


Open Access Original Research Article

Antimicrobial Activity and Elemental Composition of Sarcocephalus latifolius Fruits: An Ethnopharmacological Based Evaluation

Alsiddig Osama, Sufyan Awadelkarim, Mai Omer, Saga Yasser, Yousra Basher, Thoyba Elmabrouk, Afnan Abdalmaged

Journal of Advances in Microbiology, Page 1-5
DOI: 10.9734/JAMB/2017/33180

Sarcocephalus latifolius have been part of Sudanese ethnomedicine since long time. The current study was conducted to evaluate the antimicrobial activity of Sarcocephalus latifolius fruits and to investigate its elemental composition. The antimicrobial activities of the ethanolic crude extract and solvents fractions (hexane chloroform, acetone and aqua’s) were investigated by the disk diffusion method. These fractions were further screened for the presence of eight secondary metabolites using standard protocols. The XRF technique was used to evaluate the content of trace elements in the fruit sample ash. The chloroform fraction was the most active against both the targeted Gram positive and negative bacteria with (20, 19, 15 and 11 mm) against Bacillus subtilis (NCTC8236), Staphylococcus aureus (ATCC25923), Escherichia coli (ATCC25922) and Pseudomonas aeruginosa (ATCC27853). It also found to be active against the yeast Candida albicans (ATCC7596) with 15 mm.  S. latifolius fruits contained different elements with potassium as the most abundant metal (40.11 ppm). All these results support the medicinal and nutritional uses of this plant.

Open Access Original Research Article

Fungicidal Activity of Some Metallic Ions, Fungicides and Essential Oils for Preventing Biodeterioration of Old Manuscripts

F. Sahab, Ahmed, M. Sidkey, Nagwa, N. Abed, Nermine, Mounir, Ayah

Journal of Advances in Microbiology, Page 1-14
DOI: 10.9734/JAMB/2017/33853

Aims: The main goal of this work to investigate the fungicidal activity of some metallic ions and essential oils which were to be applied as alternative protective of synthetic fungicides for old manuscripts and documents.

Place and Duration of Study: Sample: Studies were conducted at three floors (as indoor sampling sites) of the National Library and Archives of Dar El-Kottob, Egypt during one year, between November 2012 to October 2013.

Methodology: By using the Food Poisoned Technique 11 metallic ion, 5 fungicides and 5 essential oils were used to investigate their effective against the two selected fungal isolates Fusarium oxysporum and Trichoderma viride to evaluate these protective agents by measuring their effect on fungal mycelial (linear) growth and cellulolytic activity.

Results: The results revealed that of 11 metallic ions tested only metallic ions of CoCl2, FeSO4, NiCl2, CuSo4 and ZnSO4 at 100 mM were completely inhibited the linear growth of F. oxysporum, while the same concentration of CoCl2, FeSO4, FeCl3 and NiCl2 also completely inhibit the growth of T. viride. For cellulases activity, all metallic ions at different concentrations inhibit the activity, except CoCl2, which increased the avicelase enzyme activity of F. oxysporum. Results for T. viride were little different than F. oxysporum. In vitro effect of fungicides, formaldehyde was found to be toxic to F. oxysporum and T. viride causing complete inhibition at all concentrations with percentage inhibition of 100%. Present study also indicated that, all tested essential oils were found to highly effective and gave 100% reduction in the growth of the two tested fungi at the higher concentration of 0.4%. The Anise essential oil was most effective against F. oxysporum and                   T. viride responsible for 91.80 and 100 mean % inhibition respectively followed by Rocket essential oil responsible for 82.90 and 89.97 mean% inhibition respectively.

Conclusion: Metallic ions (CH3COOH)2 Pb completely inhibited the linear growth of F. oxysporum and T. viride at low concentration (10 mM), as well as formaldehyde which gave percentage inhibition of 100% for both organisms. Anise essential followed by Rocket gave 100% reduction in the growth of the two tested fungi at the higher concentration of 0.4%.