Open Access Original Research Article

Screening of in vitro Antibacterial Activity of Rumex vesicarius (L.) Leaves Extract against Twelve Pathogenic Bacterial

Arnaba Saha Chaity, Md. Ashikul Islam, Tamanna Nasrin, Sathi Rani Sarker, Amit Kumar Dutta, Biswanath Sikdar, Md. Faruk Hasan

Journal of Advances in Microbiology, Page 1-6
DOI: 10.9734/jamb/2019/v19i430199

There is an alternative approaches from eradication of infections causes by pathogenic bacteria especially resistant bacteria. Methanol extract of Rumex vesicarius leaves were evaluated from in vitro antibacterial activity against twelve bacterial species were used which are four of them gram positive which are Streptococcus constellatus, Staphylococcus gallinarum, Staphylococcus sciuri and Streptococcus iniae and eight of them gram negative which are Aeromonas diversa, Xanthomonas campestris, Xanthomonas axonopodies, Siccibacter colletis, Edwardsielloa anguillarum, Aeromonas cavernicala, Enterobacter xiangfangenis and Vibro rotiferianus. The plant extract showed highest 12 mm zone of inhibition against Staphylococcus constellatus at the concentration of 20 μg/disc and no zone of inhibition was found from Aeromonas diversa. In minimum inhibitory concentration (MIC) test, methanol extract of Rumex vesicarious in 200μg/ml concentration showed best result against Vibrio rotiferianus. It can be concluded that methanol extracts of Rumex vesicarious leaves may be used as natural antibacterial from treatment of some diseases, especially local skin diseases.

Open Access Original Research Article

Bacteriological Assessment of Toilet Seats in a Nigerian University

T. Sampson, A. P. Esheyigba, S. S. Baridam

Journal of Advances in Microbiology, Page 1-11
DOI: 10.9734/jamb/2019/v19i430200

Exposure to enteric pathogens through direct contact with contaminated toilets surfaces and associated water is one of the major sources of disease transmission in public settings. The bacterial profile of toilet seats in students’ dormitories was investigated to determine the pattern of bacterial contamination of public toilet seats in a university setting. Samples were collected from the male and female hostels in the University, and Total Heterotrophic Bacterial Count (THBC) as well as Fecal Coliform Counts (FCC) were carried out using standard microbiological procedures. The male hostels had a mean THBC of 11.4 ± 4.9 x 105 cfu/ml and 2.7 ± 0.7 x105 cfu/ml for the water and swab samples collected from the toilet bowl (WC), respectively. The female hostels on the other hand had a mean THBC of 7.7 ± 0.6 x 105  cfu/ml and 2.0 ± 2.7 x 105 cfu/ml for the water and swab samples from the WC, respectively. The result also revealed that the water in the WC accounted for 80.7% of the bacterial isolates while the toilet seat surfaces accounted for 19.3%. However, there was a statistical difference in the bacterial counts between the male and female hostels as well as the water and swab samples from the WC (p < 0.05). A total of thirty seven isolates (37) belonging to five (5) genera were identified as Staphylococcus spp. (32.4%), Bacillus spp (32.4%), Klebsiella spp (13.5%), Escherichia coli (13.5%), as well as Coccobacilli (8.2%). This research has shown the pattern of bacterial contamination of toilet seats and the potential pathogenic bacteria that may pose health challenges. Reduction in the number of students per toilet as well as proper sanitary practice is recommended, to prevent toilet associated infections amongst students.

Open Access Original Research Article

Spatial Distribution of Bacterial Isolates from Different Abattoirs in Port Harcourt, Nigeria

Azuonwu Testimonies Chikanka, David N. Ogbonna

Journal of Advances in Microbiology, Page 1-8
DOI: 10.9734/jamb/2019/v19i430201

The constituents of wastes generated from abattoir activities create conducive environment for microbial proliferation, most of which are pathogenic. Infections caused by these microorganisms could result to zoonoses. This study was to determine the distribution of bacterial isolates and their biomass from different abattoirs in Port Harcourt. Samples like waste blood, table swab, service water, faecal matter, soil and wastewater from abattoirs in Iwofe, Rumuodomaya and Trans-Amadi were collected from October 2017 to November, 2018 and analysed using standard microbiological procedures. Results obtained revealed that the total heterotrophic bacterial count of blood samples ranged from 8.33x101 to 3.33x102 cfu/ml for Trans-Amadi and Iwofe abattoirs, table swabs ranged from 6.74x104 to 4.88x106 cfu/ml, water samples ranged from 1.56x104 to 2.07x104 cfu/ml; faecal matter had THB counts ranging from 9.97x107 to 1.06x108 cfu/g; and soil samples ranged from 1.11x1010 to 1.17x1010 g,  while wastewater counts ranged from 1.03x108 to 1.08x108 cfu/ml. The predominant Bacterial isolates were of the genera Micrococcus, Staphylococcus, Serratia, Pseudomonas, Proteus, Klebsiella, Escherichia and Chromobacterium, Serratia sp. only was isolated from Iwofe and Rumuodomaya abattoirs within April to October while Chromobacterium sp. was isolated in Trans-Amadi and Rumuodomaya abattoirs within the months of May to October. Among the isolates, Escherichia coli and Klebsiella species occurred more compared to others in all the three locations. A higher percentage of microorganisms were recorded in the month of May compared to other months. It is presumed that abattoir wastes harbour many microorganisms of public health importance. The occurrence of these microbes, most of which are enteric pathogens, poses a public health challenge as infections by them could result in illnesses such as gastroenteritis, septicaemia and pneumonia especially in the absence of good hygiene around abattoirs. Proper sanitation in abattoirs as well as management of abattoir wastes is important in reducing the spread of these microorganisms.

Open Access Original Research Article

The Effect of Moringa oleifera and Ocimum gratissimum Essential Oils and Extracts on Antimicrobial Resistant Enterobacteriaceae from Environmental Sources

C. I. Chikwendu, C. E. Okere, R. K. Obi, N. U. Nwogwugwu

Journal of Advances in Microbiology, Page 1-9
DOI: 10.9734/jamb/2019/v19i430202

The continuous increase in resistance to antimicrobials amongst the Enterobacteriaceae constitutes a growing public health threat and thus has necessitated the need to continuously search for alternative antimicrobial chemotherapy. This study was aimed at evaluating the effects Moringa oleifera seed and Ocimum gratissimum plant extracts and essential oils on antimicrobial resistant Enterobacteriaceae isolated from aquatic sources. Two hundred isolates of Klebsiella pneumoniae and Escherichia coli were recovered from two different environmental sources. The susceptibility of the isolates to ten (10) different antimicrobials was examined by the Kirby-Bauer technique. The isolates were also tested for extended β-lactamase production (ESβL) by the modified double disc synergy test and the susceptibility of the isolates to essential oils and extracts from Moringa oleifera seeds and Ocimum gratissimum leaves was analysed using the agar - well diffusion assay. In addition, the phytochemical analysis of the extracts was carried out to determine their constituents. The river water isolates recorded high resistance rates for the following antibiotics: Ampicillin (99%), cefotaxime (83%), imipenem (77%) and low rates for levofloxacine (19%), while the aquaculture isolates expressed high resistance rates to ampicillin (95%) ceftazedime (86%), ertapenem (65%), and low rates to aztreonam (8%). Thirteen (37%) isolates out of 35 tested were positive for ESβL   production, four isolates from river water and nine from aquaculture. Antimicrobial analysis of the essential oils against the ESBL producers showed no inhibitory activity while the plant extracts produced zones of inhibition and minimum inhibitory concentrations of between 1.32 and 2.70 mg/ml for the two plant extracts tested. Phytochemical analysis showed the presence of alkaloids, saponins, tannins, flavonoids and glycosides in different quantities. This study has shown that crude extracts of Moringa oleifera seeds and Ocimum gratissimum leaf could become a potential alternative in the treatment of infections due to antimicrobial-resistant Enterobacteriaceae.

Open Access Original Research Article

Isolation, Identification and Evaluation of Egyptian Bacillus sp. Isolates for Producing Poly-γ-glutamic Acid

Rania F. Ahmed, Hala Badr Khalil

Journal of Advances in Microbiology, Page 1-13
DOI: 10.9734/jamb/2019/v19i430203

Poly-γ-glutamic acid (γ-PGA) is a non-toxic, biodegradable, and water-soluble polymer secreted from different microbes. We isolated forty-nine Bacillus spp. isolates generating PGA from the soil of different Egyptian regions. A total of 18% of these isolates were found to highly produce PGA in the range of 5- 8 gl-l. Two of them, B44 and B42, were identified by the16SrRNA DNA sequence, and they shared 81% of similarity. The most similar DNA sequences to B44-16SrRNA were Bacillus sp. (FJ607057.1) and Bacillus sonorensis (KP236346.1) matching 99% and 94% of similarity, respectively. However, B42-16SrRNA was similar 99% to several Bacillus species. The tree-building algorithm MEGA-X constructed the phylogenetic tree of 16SrRNA DNA sequences for Bacillus 44 and Bacillus 42 strains along with other similar Bacillus species revealing the distance between them. We also boosted the PGA production of both strains. Bacillus 44 strain revealed the highest accumulation level of PGA at 35°C and 72 h of incubation using medium M with inoculum size and agitation speed 3% and 250 rpm, respectively. Both strains secreted the PGA biopolymer with a molecular mass of 55 kDa. This investigation is an attempt of boosting promising Egyptian Bacillus sp. isolates for PGA production that may be a seed for industrial production.