Open Access Original Research Article

Functional and Rheological Profile of LAB-fermented Bambara Groundnut (Vigna subterranean (L)) Flour

C. O. Chude, C. C. Nwagbo, E. F. Okpalanma, B. O. Uba

Journal of Advances in Microbiology, Page 1-9
DOI: 10.9734/jamb/2021/v21i1030387

Lactic fermentation is commonly employed to improve protein digestibility and overall nutritional quality of grains foods. This study evaluated the functional and rheological properties of flour samples from Bambara groundnut fermented with Lactobacillus plantarum [NRRL B-4306] and Lactobacillus fermentum [NRRL B-1932] obtained from the United States Department of Agriculture. Functional profile such as particle size index, water absorption capacity, swelling capacity, and least gelation concentration of the flour were determined; as well, amylograph and maturograph evaluations were used to determine the rheological properties and the results presented as average, minimum, and maxi­mum values. Particle size determination observed that 150, 125, 105 µ orifice did not readily accommodate particles from the non-inoculated samples while the inoculated samples passed through 150 and 125 µ but did not readily pass through 105 µ orifice. Bioprocess with lactic acid bacteria increased the water absorption capacity of the flour samples from 346.5 to 386.4%, the least gelation concentration decreased from 5.3 to 4.1%, while swelling capacity increased from 14.9 to 23.2 mg/100 g for non-inoculated and inoculated flours, respectively. Rheological investigations show evaluations for amylograph and maturogram determinations. Values obtained for amylograph indicate that temperature at start of gelatinization was peak at 63.8 and 63.00C for non-fermented and LAB-fermented flour with no significant (p ˂ 0.05) difference, while temperature at maximum viscosity and maximum viscosity had significant (p ˂ 0.05) values of 92.1 and 76.00C, as well as 730 and 265 brabender units (BU), respectively. Thus, amylograph quality of the fermented flour sample was indicated by the maximum viscosity which is significantly higher in the case of non-inoculated flour sample. The maturograph evaluation also recorded the maturation behavior of the dough prepared from the test flours after the proofing time (fermentation rest) by means of a sensing probe which records the elasticity of the mature dough every 2 min and produces the typical zigzag form of the maturogram. This action was recorded in maturograph units (MU) on the strip-chart with values of 44 and 28 min for final proof time, 750 and 610 MU for dough level, 210 and 220 MU for dough elasticity, as well as 10 and 12 min for proofing stability, determined respectively for non-fermented and LAB-fermented flour samples. LAB-fermentation demonstrated to improve the functionality and rheology of Bambara groundnut flour and the production process could be further controlled to achieve products of optimal quality.

Open Access Original Research Article

Wound Healing and Antimicrobial Effects of Azadrachita indica Leaves Extracts on Eschericha coli Infected Diabetic Wounds using Albino Rat Model

I. M. Izundu, C. O. Anyamene, N. C. N. Okoro, O. I. Okafor, M. O. Echeta

Journal of Advances in Microbiology, Page 10-20
DOI: 10.9734/jamb/2021/v21i1030388

The wound healing and antimicrobial effects of Azadirachta indica leaf extracts were evaluated on Eschericha coli infected diabetic wounds using albino rat model. The study was a cross-sectional work done between January and June, 2020. Eschericha coli was isolated and identified from 50 infected diabetic patients using Eosin methylene blue and standard biochemical tests. The crude extracts of A. indica were gotten using ethanol and water by soxhlet method. The phytochemical such as saponins, phenols, tannins, flavonoid and alkaloids were determined quantitatively and qualitatively using standard method. In vitro antimicrobial effect of extracts and their combination were evaluated. The wound healing effects of the extracts were done using six weeks old albino rat model. Out of 50 swab samples of infected diabetic wounds, 30 isolates were obtained which E. coli was 20% of the bacterial isolates from the infected wound. The phytochemical analysis of the extracts showed the presence of saponin, flavonoids, steroid, alkaloids, tannins and phenol. Among the leaf extracts analysed, A. indica ethanol extract has the highest inhibition zone against E. coli (10.67±1.15 mm) at 500 mg/ml and 1000 mg/ml concentration. The Minimum inhibitory concentration (MIC) was 250 mg/ml while the Minimum Bactericidal Concentration (MBC) was 1000mg/ml. Diabetic and healthy groups of albino rats were treated after 1 week of infection. Comparing the negative control rats witsh those treated with daily topical application of the leaf extracts, showed significant reduction in wound size and rapid healing (P = 0.05). Comparing with positive control, the leaf extracts have almost the same healing effect with the positive control (povidone iodine). The leaf extracts of A. indica possess antimicrobial properties for E. coli especially the ethanol extract which heals faster than aqueous extract and can be used as an alternative for healing infected non diabetic and chronic diabetic wounds.

Open Access Original Research Article

Antioxidant Property and Oral Glucose Tolerance of Stem Extract of Andrographis paniculata – Nees

E. O. Awoyinka, A. O. Ogundare, T. T. Adebolu, Adeloye Adedeji Isaac

Journal of Advances in Microbiology, Page 21-28
DOI: 10.9734/jamb/2021/v21i1030389

This research aims to investigate the antioxidant property and oral glucose tolerance of stem extract of Andrographis paniculata using standard methods. The antioxidant activity of the extracts were assessed using total phenol, total flavonoid, ABTS (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)), nitric oxide, GSH (gluthatione), super oxide, DPPH [1,1-di-phenyl-2-picryl hydrazyl] and ascorbic acid.  The oral glucose tolerance of methanol stem extract of A. paniculata was carried out using wistar albino rats. The Wistar albino rats were divided into six groups consisting of five rats each.  Group 1 was given water only, group two to group five were induced with 2g/kg of glucose. After 30 minutes, group 3 and 4 were treated with the doses of 15 mg/kg and 30 mg/kg of the extract while group 5 was treated with glibenclamide respectively. The blood glucose level of each group was monitored for 2hours at 30 minutes interval and compared with the control that was given water only. The result shows that the extracts were able to scavenge free radicals but methanol stem extract of A. paniculata performed better in scavenging free radicals as compared to others. The blood sugar levels of the rats treated with doses of 15 and 30 mg/kg of methanol stem extract of A. paniculata were significantly lower than the group of rats that were fed with only glucose and the group of rats treated with glibenclamide. The glucose-lowering efficiency of the extract was between 60-120 minutes. Findings from this present study revealed that A. paniculata is a potential plant that can scavenge free radicals and also possess hypoglycemic activity.

Open Access Original Research Article

Serologic and Molecular Detection of Mycoplasma gallisepticum in Layer Flocks in South Marmara Region of Turkey

Elçin Günaydın, Özlem Kardoğan, Gülşen Goncagül, Yavuz Çokal

Journal of Advances in Microbiology, Page 29-37
DOI: 10.9734/jamb/2021/v21i1030390

Background: Due to the economic impacts of Mycoplasma gallisepticum (MG) infection in poultry, it is essential to have a fast, reliable and accurate diagnostic test to diagnose the infection.

Aims: It was aimed to examine the presence of MG in the South Marmara Region of Turkey where extensive commercial layer flocks exist by RPA, ELISA and real-time PCR.

Materials and Methods: In the study, 981 sera and 160 tracheal swab samples (20 swabs per each flock) obtained from eight layer flocks were examined for the presence of MG-antibody by RPA, ELISA, and the presence of MG by real-time PCR, respectively.

Results: MG-seropositive flock rate was determined to be 100% by RPA. Twenty-three of the RPA positive sera in each flock LA, LB, LC, LD, LF, LG, and 17 RPA positive sera in flock LE (due to 17 positive RPA sera obtained) were examined for the presence of MG antibody by ELISA, and MG-seropositive flock rate was determined to be 87.5%. As a result of the examination of a total of 32 tracheal swab samples (20 swabs perflock/5 swabs=4 pooled samples, 8 flocksX4 pooled samples= 32 samples) for the presence of MG, real-time PCR positive flock rate was found to be 75%.

Conclusion: To decide the flock whether it is infected or not and the initiate effective preventive measures against MG infection as soon as possible; serology should be applied simultaneously with bacteriology and/or PCR to prevent time loss due to shortcomings of serological tests used as primary screening test such as cross reactions, sensitivity and specificity problems.

Open Access Original Research Article

Determination of Microbial Pathogens and its Abundance in Fresh Kunun-Zaki Drinks: Huge Threat to Public Health

Samuel E. Odo, Daniel A. Nwaubani, Gloria N. Ebe, John I. Idume, Onyemaobi W. Okengwu

Journal of Advances in Microbiology, Page 38-42
DOI: 10.9734/jamb/2021/v21i1030391

This study investigated the presence and abundance of microbial pathogens in fresh locally produced, packaged and distributed kunun-zaki drinks. A total of 20 samples were randomly purchased from 20 vendors and hawkers. Each of the samples obtained was tenfold serially diluted using sterile peptone water. From the appropriate dilutions, 0.1ml were removed and spread plated on Salmonella-Shigella agar, Mannitol salt agar, and Eosin methylene blue agar plates. The inoculated plates were then incubated at 37°C for 24 hours. This study found that of the 20 kunun-zaki samples investigated, 70% were contaminated by Staphylococcus aureus which ranged from 1.0x104 to 1.21x105 (CFU/ml). Salmonella spp ranged from 1.2x104 to 4.1x104 (CFU/ml), and contaminated 60% of the samples. Escherichia coli ranged from 0.2x104 to 1.1x104 (CFU/ml) and was found in 45% of the samples. The result showed that the locally produced, packaged and distributed kunun-zaki drinks were highly contaminated by foodborne microbial pathogens and it makes it unsafe for human consumption. It further showed that public health is put at risk when unsafe locally produced kunun-zaki beverage is consumed; hence, local producers and Agencies saddled with the responsibility to monitor, supervise and certify food safety must strictly ensure the protection of consumers and public health by insisting that traditional methods of production, packaging and distribution of kunun-zaki drinks follow, maintain and sustain standards that guarantee quality, safety and accessibility. Consumers must resist the urge to purchase kunun-zaki drinks from unverified sources; producers, vendors and hawkers.

Open Access Original Research Article

Identity and Antibiogram of Bacterial Isolates from Owerri Modern Abattoir, Imo State, Nigeria

Joy Nkeiruka Dike-Ndudim, Roseline Nwanneka Ugwuegbu, Henry Chidozie Amah, Chizaram Winners Ndubueze, Emeka Simon Anikwo

Journal of Advances in Microbiology, Page 43-54
DOI: 10.9734/jamb/2021/v21i1030392

Aim: The identity and antibiogram of bacterial isolates from Owerri modern abattoir in Imo State, Nigeria, was investigated with the aim of determining the bacterial profile of the abattoir and their susceptibility pattern to commonly used antibiotics.

Study Design: Cross sectional study

Place and Duration of Study: This study was carried out in Owerri Modern Abattoir located within Owerri metropolis from June to November, 2020.

Methodology: Questionnaires were used to obtain participants’ consent, demographic data and sanitary practices in the abattoir.  Samples were taken and bacteriological analysis of the samples done using pour plate method. Disc diffusion antibiotic susceptibility testing and minimum inhibitory concentration were performed after colony counting, identification and characterization of the isolates using standard microbiological and biochemical techniques.

Results: Mean viable bacterial counts were generally high with highest counts from contaminated soil (6.13x106CFU/ml) and least from workers hands (1.17x106CFU/ml). Escherichia coli had the highest prevalence (18.0%), with the highest counts from soil (3.10%). Vibrio cholerae recorded the least prevalence (0.62%), and was isolated only from washing water. High resistance to antibiotics was observed.

Conclusion: Government authority and the general public are advised to ensure adequate environmental sanitation and proper cooking of meat before consumption in order to mitigate the incidence of infection and antibiotic resistance.

Open Access Original Research Article

Occurrence of Aflatoxins in Rice Intended for Infant Flour Production in Ouagadougou, Burkina Faso

Hamidou Compaoré, Serge Samandoulougou, Clarisse S. Compaoré, Alima Bambara, Hissein Ratongué, Lassina Traoré, Hagrétou Sawadogo-Lingani

Journal of Advances in Microbiology, Page 55-66
DOI: 10.9734/jamb/2021/v21i1030393

A total of four samples of rice intended for infant flour production in Ouagadougou were received at the Physico-chemistry laboratory of Food Technology Department (DTA) for quality control. The latter were also tested for Aspergillus section Flavi presence and analyzed for aflatoxins B1, B2, G1 and G2 content using high performance liquid chromatography (HPLC). Among the twenty (20) strains of mold isolated from these samples, three Aspergillus section Flavi were obtained and cultivated in “Aspergillus flavus and parasiticus Agar (AFPA)” to ascertain if they belong to Aspergillus flavus or Aspergillus parasiticus species. The qualitative ability of aflatoxin production was also performed by fluorescence emission under ultra violet light at 365 nm after four days of incubation at 30 °C on Coconut Agar Medium (CAM). Statistical analysis results showed that 75% of samples were contaminated with total aflatoxins (AFs) with contents ranging from 0.54 ± 0.06 to 2.40 ± 0.07 µg/Kg. Aflatoxin B1 (AFB1) and aflatoxin B2 (AFB2) were detected in two contaminated samples. AFB1 had the highest concentration as compared with other aflatoxins. A significant level of contamination (p< 0.0001) was observed in sample R441 compared to other sample types.

Open Access Original Research Article

Microbiological Quality Assessment and Identification of Antibiotic Resistant Bacteria at Different Stages of the Milk Supply Chain in Dhaka City of Bangladesh

Abira Nowar, Ila Ismail, Raisa Binte Iqbal, Sharmin Rumi Alim

Journal of Advances in Microbiology, Page 67-76
DOI: 10.9734/jamb/2021/v21i1030394

Aims: Milk works as an excellent medium for bacterial growth and can turn into a fatal source of food borne diseases when consumed without pasteurization. This study was carried out to examine the microbiological quality of milk from three different points of milk supply chain to investigate whether the dairy stakeholders are maintaining the consumer safety or not.

Study Design: A cross sectional study

Place and Duration: The study took place at the Food Microbiology lab of Institute of Nutrition and Food Science, University of Dhaka from November 2019 to February 2020.

Methodology: A total of 60 samples were studied including raw milk from collection centers, unpackaged pasteurized milk from processing plants and packaged pasteurized milks from retail shops. After carrying out the microbiological analysis the samples were examined for determining the total bacterial count (TBC) and total coliform count (TCC). Antibiotic susceptibility test was done using disk diffusion assay and detection of virulent gene in Salmonella spp. was done by Polymerase Chain Reaction (PCR) using specific invA primer.

Results: The results revealed that all raw milk samples were substandard in terms of TBC and TCC and pasteurized milks from processing plants maintained the standard quality. Importantly, packaged pasteurized milk samples from retail shops had high TBC (>4.0× 104 CFU/mL) and TCC (1.2×103 CFU/mL) containing Pseudomonas, Micrococcus, Streptococcus, Salmonella, Proteus, Staphylococcus, Bacillus and E. coli. Bacteria like Salmonella (75%), Proteus (62.5%) and Vibrio (62.5%) possessed high Multiple Antibiotic Resistance (MAR) index and showed resistance towards antibiotics namely Ampicillin, Amoxicillin, Erythromycin and Colistin. Through further molecular analysis we detected invA virulent gene one of the Salmonella isolates which was collected from the pasteurized milk samples of the retail shops.

Conclusion: High bacterial load in raw milk and packaged pasteurized milk indicate that the milk we consume is substandard in microbiological quality. Precautionary measurements and careful processing of milk may reduce the prevalence of microbiological contamination in the milk supply chain.

Open Access Original Research Article

Production of Glucose Isomerase from Streptomyces roseiscleroticus

Okwuenu Prosper Chinyelum, Onosakponome Iruogene, Oparaji Emeka Henry

Journal of Advances in Microbiology, Page 87-94
DOI: 10.9734/jamb/2021/v21i1030396

This study was aimed at the isolation and characterization of a microbial strain capable of producing glucose isomerase. Microbial strain was isolated from soil using starch casein agar as a differential media. The isolated microbial strain was capable of producing glucose isomerase which was tested using 2, 3, 5 - triphenyltetrazolium solution as a chromogenic substrate. The microbial strain was identified as Streptomyces species based on its morphological and microscopic characteristics. It was further subjected to molecular characterization using 16S rRNA sequencing and was subsequently confirmed as Streptomyces roseiscleroticus. Glucose isomerase was produced from Streptomyces roseiscleroticus after 120 hr of submerged fermentation at pH 6.8 and at 37°C utilizing xylose as the sole carbon source and a compendium of peptone, beef and yeast extracts as nitrogen sources. These findings suggest that the microbial strain, Streptomyces roseiscleroticus can be a useful bacterial source for the production of glucose isomerase needed for commercial and industrial utilization.

Open Access Review Article

Association of L-form Bacteria with Plants and their Application in Biological Control of Phytopathogenic Fungi and Bacteria: A Review

P. W. H. K. P. Daulagala

Journal of Advances in Microbiology, Page 77-86
DOI: 10.9734/jamb/2021/v21i1030395

L-form bacteria with modified or no cell walls are a special group of bacteria derived or induced from cell walled forms following suppression of their rigid cell wall. They have been used to establish non-pathogenic symbioses with a wide range of plants. These L-form-plant symbioses have been shown to confer resistance against the subsequent challenge of the associated plants by both fungal and bacterial pathogens. As the world population increases, the demand for food also increases and hence control of plant diseases is of paramount importance in producing enough agricultural crops to fulfil the food demand. Plant disease management using chemical fungicides and pesticides etc. is not an ecofriendly approach and hence researchers look for alternative options such as the use of biocontrol agents which are ecofriendly and sustainable. This review paper highlights the published information on the potential of applying L-form bacteria as a biological control agent in management of plant diseases caused by pathogenic microorganisms.