Advanced Journal of Microbiology Research

Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 13 (5), pp. 001-009, May, 2019. © International Scholars Journals

Full Length Research Paper

Growth and exopolysaccharide production by Weissella sp. from low-cost substitutes for sucrose

Chintana Tayuan¹*, Gerald W. Tannock² and Sureelak Rodtong¹

¹School of Microbiology, Institute of Science, Suranaree University of Technology, Nakon Ratchasima, 30000, Thailand.

²Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand.

Accepted 10 March, 2019

Abstract

Homopolysaccharides produced from sucrose by lactic acid bacteria (LAB) are of interest as natural additives to improve textural properties of foods. The production of exopolysaccharide (EPS) by WEISSELLA strains, which had been isolated from a traditional Thai food (plasom), was investigated using sugarcane molasses and white sugar from sugarcane as substrates in comparison to analytical grade sucrose. EPS production was evaluated at 30°C for 48 h. EPS production and bacterial growth were influenced by the type of carbon source used in culture medium. The highest EPS concentration was obtained in the medium supplemented with white sugar from sugarcane as a sole carbon source by WEISSELLA sp. PSMS4-4. The optimal concentration and factors affecting the production of EPS, that is, cultivation temperature and initial pH of medium, were determined. The highest EPS production of 8.65 g/l was attained in culture with an initial pH of 7.0, temperature of 30°C, and white sugar concentration of 5%. This study shows the first report on the production of WEISSELLA EPS using low-cost substitutes for sucrose and provides knowledge of factors influencing the production of the polymer.

Key words:  Exopolysaccharide, sucrose, white sugar from sugarcane, lactic acid bacteria, Weissella.

Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 13 (5), pp. 001-009, May, 2019. © International Scholars Journals

Full Length Research Paper

Prevention of emergence of fusidic acid and rifampicin resistance in Staphylococcus aureus using phytochemicals

Bhone Myint Kyaw¹, Shuchi Arora², Khaing Nwe Win¹ and Lim Chu Sing Daniel¹*

¹School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798.

²School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459.

Accepted January 25, 2019

Abstract

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the major causes of nosocomial and community infections. It has shown resistance to most of the currently available antibiotics and nicknamed ‘super bug’. Anti-staphylococcal activities of tannic acid, quercetin and gallic acid ethyl ester in combination with fusidic acid and rifampicin were determined against five strains of S. aureus, including three clinical strains. Tannic acid and quercetin were found to be synergistic with fusidic acid and rifampicin. The effects of these combinatory pairs on the adaptive resistance of S. aureus were also studied. The strains were studied for ten incubation cycles under continuous influence of fusidic acid/rifampicin alone and in combination with fixed dose of phytochemicals. The minimum inhibitory concentrations (MIC) of the exposed strains were determined after every cycle to study their resistance to the antibiotic. Based on the results at the end of the tenth cycle, the fusidic acid/rifampicin exposed strains gradually selected for resistance at higher MIC values. On the other hand, the combination exposed strains demonstrated stable MIC values for the antibiotics. The results suggested prevention or delay of fusidic acid and rifampicin resistance by adding synergistic phytochemicals.

Key words: Staphylococcus aureus, antibiotic resistance, antibiotic combination, phytochemicals.

Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 13 (5), pp. 001-007, May, 2019. © International Scholars Journals

Full Length Research Paper

Hepatitis C virus infection in uremic patients on maintenance hemodialysis: A follow up study for 150 months

Chen Yuqiang, Wang Niansong*, Sheng Xiaohua, Zhang Xiaoguang, Yan Yan, Yu Gang, Cui Yongping and Tang Lingquan

Department of Nephrology and Rheumatology, Shanghai No. 6 Hospital, Shanghai Jiao Tong University, Shanghai, China.

Accepted 19 March, 2019

Abstract

We aimed to delineate the incidence of hepatitis C virus (HCV) infection and HCV seroconversion (SC) in maintenance hemodialysis (HD) patients and to evaluate the effect of isolation measures on HCV in HD unit. From June 1998 to June 2010, 2465 maintenance HD patients in our HD unit were enrolled in, and the anti-HCV ELISA and HCV nucleic acid testing were consecutively performed every six months. The results showed the prevalence rates of HCV antibody detected consecutively every six months were 54.7, 53.8, 52.6, 53.0 , 51.2, 45.9, 45.5 and 48.2% before 2002 (without isolation measures) and 35.6, 33.7, 33.7, 31.7, 30.4, 28.4, 27.2, 24.5, 20.8, 19.4, 16.6, 14.4, 15.3, 15.2, 12.5, 11.9 and 10.0% since 2002 (with isolation measures), respectively. HCV SC occurred in 238 patients during the follow-up period. 1077 patients were followed for 1 to 12 months, of which 49 (4.5%) had SC for HCV. The SC rate increased to 75% in 8 patients followed for 139 to 150 months. Taken together, we conclude that the dialysis environment is responsible for transmission of HCV either due to common usage of the machines or to the fact that the HCV positive patients are not isolated. The application of isolated hemodialysis of anti-HCV positive patients plus strict supervised universal infection control techniques significantly effect on the long-term prevalence of HCV antibody and SC in HD patients.

Key words: Hemodialysis, hepatitis C virus, seroconversion, blood transfusion, nosocomial transmission.

Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 13 (5), pp. 001-005, May, 2019. © International Scholars Journals

Full Length Research Paper

Antimicrobial activity of pomegranate rind peel extracts

Hany M. Yehia¹*, Manal F. Elkhadragy² and Ahmed E. Abdel Moneim²

¹Department of Food Science and Nutrition, College of Food and Agriculture Sciences, King Saud University, Al-Riyadh, KSA, Saudi Arabia.

²Department of Zoology and Entomology, Faculty of Science, Helwan University, Egypt.

Accepted 19 March, 2019

Abstract

The pomegranate, Punica granatum L., is an ancient, mystical, unique fruit borne on a small, long-living tree cultivated throughout the Mediterranean region. Pomegranate is used in several systems of medicine for a variety of ailments. The synergistic action of the pomegranate constituents appears to be superior to that of single constituents. P. garantum, have been reported to have antimicrobial activity against a range of Gram positive and negative bacteria. Pomegranate formulations containing ferrous salts have enhanced although on short-term. The aim of this experiment is to determine the antimicrobial activities of combinations of pomegranate rind extract with range of metal salts with the addition of vitamin C. Phytochemical analyses was made to determine the active inhibitors in rind extract, including phenolics and flavonoids.

Key words: Antimicrobial activity, pomegranate rind extract, phenolics, flavonoids.

Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 13 (5), pp. 001-006, May, 2019. © International Scholars Journals

Full Length Research Paper

In vitro activities of Eucalyptus camaldulensis Dehnh. and Eucalyptus torelliana F. Muell. against non-tuberculous mycobacteria species

Temitope O. Lawal¹*, Bolanle A. Adeniyi¹, Olakunle S. Idowu² and Jones O. Moody³

¹Department of Pharmaceutical Microbiology, University of Ibadan, Nigeria.

²Department of Pharmaceutical Chemistry, University of Ibadan, Nigeria.

³Department of Pharmacognosy, University of Ibadan, Nigeria.

Accepted 23 March, 2019

Abstract

The extracts of Eucalyptus camaldulensis Dehnh. and Eucalyptus torelliana F. Muell. (Myrtaceae) were screened against four non-tuberculous mycobacteria species: Mycobacterium fortuitum ATCC 684, Mycobacterium smegmatis ATCC 19420, Mycobacterium phlei ATCC 19240 and Mycobacterium abscessus. The agar diffusion method was used to investigate the activity of these plants at 1 and 2 mg/ml concentration. The methanol extracts exhibited the highest activity against the test organisms, the most susceptible being M. fortuitum ATCC 684. The minimum inhibitory concentration (MIC) value for the bioactive extracts ranged between 1 to 2 mg/ml while minimum bactericidal concentration (MBC) value was 2 to 4 mg/ml. Bactericidal activity of the methanol extracts of E. camaldulensis on M. fortuitum ATCC 684 was investigated using the viable counting technique. The leaf extracts at 4 mg/ml (4 × MIC) and 8 mg/ml (8 × MIC) gave 80.49 and 100% kill of the organism respectively at 24 h exposure time while the stem bark extracts at the same concentrations afforded 67.35 and 100% kill respectively after 24 h of exposure. The activities demonstrated by these plants support their use in the treatment of cough associated with most pulmonary diseases; and suggest that these plants may be of therapeutic importance for the treatment of infections caused by the non-tuberculous mycobacteria (NTM).

Key words: Eucalyptus camaldulensis Dehnh., Eucalyptus torelliana F. Muell., non-tuberculous mycobacteria, antimycobacterial activity, in vitro.

Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 13 (5), pp. 001-004, May, 2019. © International Scholars Journals

Full Length Research Paper

Antimicrobial activity of Mirabilis Jalapa and Dichrotachys cinerea against biofilm and extended spectrum of beta lactamase (ESBL) producing uropathogenic Escherichia coli

P. Poovendran¹, N. Vidhya¹ and S. Murugan²*

¹Department of Microbiology, Dr.N.G.P Arts and Science College, Coimbatore- 641 048, India.

²Department of Biotechnology, School of Biotechnology and Health Sciences, Karunya University, Coimbatore-641 114, India.

Accepted 22 March, 2019

Abstract

The aim of this study was to evaluate the antimicrobial efficacy of Mirabilis jalapa and Dichrotachys cinerea against biofilm and extended spectrum of beta lactamase (ESBL) producing uropathogenic Escherichia coli (UPEC). M. jalapa and D. cinerea are widespread medicinal plants traditionally used to treat infectious diseases. Aqueous, acetone and ethanol extracts of leaves of M. jalapa and D. cinerea were tested for antimicrobial activity invitro by the agar well diffusion method. Ethanol extract of M. jalapa leaves exhibited antimicrobial activity against all tested biofilm producing UPEC strains, whereas it inhibited only the ESBL producing UPEC strains 42 and 96. Similarly, the acetone extract of M. jalapa leaves inhibited the growth of biofilm producing UPEC strains 1, 17 and 82, whereas it inhibited only the ESBL producing UPEC strains 42 and 96. Ethanol extract of D. cinerea leaves exhibited inhibitory activity against all tested biofilm producing UPEC strains, whereas it inhibited only the ESBL producing UPEC strain 87. Similarly, the acetone extract inhibited only the growth of biofilm producing UPEC strain 82, whereas it inhibited the growth of ESBL producing UPEC strains 87 and 96. The aqueous extracts of M. jalapa and D. cinerea leaves failed to show any inhibitory effect against both biofilm and ESBL producing UPEC strains. These antimicrobial properties seem to be related to the presence of alkaloids, tri-terpenoids and tannin contents in M. jalapa and D. cinerea. The present study shows that crude extracts of M. jalapa and D. cinerea especially the acetone and ethanol extracts exhibited significant activity against biofilm and ESBL producing Uropathogenic E. coli strains.

Key words: Biofilm, extended spectrum of beta lactamase (ESBL), Escherichia coli, Mirabilis jalapa and Dichrotachys cinerea, antimicrobial activity.