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Antifungal resistance remains a significant public health threat, yet poorly investigated. This study for the first time investigated the antifungal profile of moulds isolated from groundwaters in a rural community of Osun State, Southwest Nigeria. Groundwater samples were collected during dry and rainy seasons, and processed for mould isolation using standard methods. The isolates were presumptively identified and screened for in vitro susceptibility using 4 antifungals conventionally employed in clinical cases. Multiple antifungal resistance phenotypes and indices were equally evaluated. Representative of each putatively identified species were confirmed using molecular techniques. A total of 29 and 27 moulds were obtained during the dry and rainy seasons, respectively. Genus Aspergillus was the most prevalent (30.4%). Of the 56 isolates subjected to antifungal susceptibility testing, 55(98%) were resistant to fluconazole, followed by flucytosine 49(88%), ketoconazole 45(80%) and amphotericin B 31(55%). Exactly 46 isolates were multidrug-resistant, 23(50%) each, to 3 and 4 drugs, respectively. The multiple antifungal resistance index (MARI) evaluated was 1 in all the samples A-Q, except C (0.75), transcending the threshold limit of 0.2, indicating the isolates to be of high antifungal usage origin. The molecularly identified species had 99–100% similarity with reference strains from GenBank and evolutionary relationship of taxa revealed 10 distinct clades. The outcome of this study reveals a rise in the frequency of antifungal resistance in moulds towards standard drugs, thus, advocating for adequate investigations targeted at monitoring antifungal resistance in groundwater milieus. [ABSTRACT FROM AUTHOR]

Background: This work investigates the production of citric acid from cashew apple juice, an abundant waste in the processing of cashew, using a local strain of Aspergillus niger and the application of the citric acid as a coagulant for the production of soy cheese. Fungal isolates were obtained from a cashew plantation in Ogbomoso, Nigeria, using potato dextrose agar. Further screening was undertaken to determine the qualitative strength of acid production by the fungi on Czapek-Dox agar supplemented with bromocresol green, with the development of yellow zone taken as an indication of citric acid production. Thereafter, the best producing strain was cultivated in a cashew apple juice medium. Results: Out of 150 fungal isolates generated from the cashew plantation, 92 (61.3%), 44 (29.3%) and 14 (9.3%) were obtained from cashew fruits, soil and cashew tree surfaces, respectively. Different strains of fungi isolated include Aspergillus niger, A. flavus, A. foetidus, A. heteromorphus, A. nidulans and A. viridinutans. The isolates produced yellow zonation of 0.4–5.5 cm on modified Czapek-Dox agar; the highest was observed for a strain of A. niger LCFS 5, which was identified using molecular tools. In the formulated cashew apple juice medium, the citric acid yield of LCFS 5 ranged 16.0–92.8 g/l with the peak obtained on the 10th day of fermentation. The citric acid produced was recovered using the double precipitation method with Ca(OH)2 and H2SO4 having ≈ 70% purity of citric acid on HPLC. The citric acid acted as a coagulant to produce soy cheese with 66.67% acceptability by panelists. Conclusion: This work has extended the frontiers of valorization of cashew waste by a strain of A. niger to produce citric acid in high yield, with potential application in food industries. [ABSTRACT FROM AUTHOR]

Indigenous fermentation of Parkia biglobosa seeds rely on back slopping, so there is no control of organisms that ferment the seeds or a definite standardization of innocula during the fermentation. This study is aimed at evaluating the physiochemical, microbiological, nutritional and sensory acceptability of fermented Parkia biglobosa seeds (daddawa) using different densities of Bacillus subtilis. Isolation of B. subtilis was carried out using MYP agar and the identification was done using biochemical and molecular techniques. During the process of fermentation, the Parkia biglobosa seeds (daddawa) were assessed for pH, titrable acidity, temperature, aerobic mesophilic bacterial count, proximate composition and sensory evaluation using standard procedures. Results show that highest increase was observed in pH (6.3±0.01 to 7.41±0.01) and a corresponding highest decrease in titrable acidity was observed (0.05±0.00 to 0.01±0.00) in Parkia seeds innoculated with 6.0×108 CFU/ml during the fermentation. An increase in temperature (24 to 30oC), aerobic mesophilic bacterial count (6.01±0.01 to 6.78±0.51) in uninnoculated Parkia seeds was also observed at 72h of fermentation. There was highest increase in protein content from 39.79±0.01 at 0hr to 47.73±0.00 in Parkia seeds innoculated with 3.0×108 CFU/ml at 72h of fermentation, but the content was not statistically different when compared with the other treatments. Highest decrease was observed in carbohydrate from 23.73±0.00 at 0hr to 17.70±0.00 in Parkia seeds innoculated with 6.0×108 CFU/ml at 72h of fermentation. Sensory evaluation showed that the judges preferred fermented Parkia biglobosa seeds treated with 1.5×108 CFU/ml of innoculum and control with a percentage likeness of 100% compared to the other treatments (3.0×108 CFU/ml, and 6.0×108 CFU/ml) with a percentage likeness of 40% and 0% respectively after 72h of fermentation. Statistically, there was no significant difference (p>0.05) between the different treatments in terms of protein contents. However, there is a general lower nutritional content observed in the uninnoculated Parkia seeds. Better texture, color and odor were also observed in the Parkia seeds innoculated with starter cultures as compared to the uninnoculated Parkia seeds. Conclusively, it was observed that the use of starter culture in higher density does not necessarily increase its nutritional value but rather, speed up the fermentation process. [ABSTRACT FROM AUTHOR]

Background: Caries is controlled by several factors including exposure to diets rich in carbohydrates, tooth susceptibility, and the presence of some oral flora bacteria such as Streptococcus mutans (S. mutans) and Lactobacilli sp. Tooth demineralisation occurs when the pH in the oral cavity is lower than the critical pH of 5.5 which occurs because of the production of acid by the acidogenic bacteria in the oral flora when they break down sugars (substrate) for energy., Objective: The objective of this study was to determine the salivary Streptococcus mutans and Lactobacillus counts and their association with resting pH of saliva and dental caries in pre-school children in Lagos., Materialsand Methods: Fifty preschoolers with and without caries were recruited from the dental clinic and staff primary school in Lagos University Teaching Hospital, Idi-araba respectively. Saliva was collected in Thioglycollate media. The resting pH of the saliva was measured immediately in the clinic with a pH meter (Jenway pH meter, PHS 25). In the laboratory, the samples were streaked on Mitis salivarius bacitracin agar (MSB) and Rogosa agar for S. mutans and Lactobacillus respectively and incubated anaerobically for 48 hours at 37°C. Biochemical tests and morphological characteristics of colonies were used to identify S. mutans and Lactobacillus., Results: The children were aged between 45 to 71 months with a mean age of 56.66 7.17 months. The mean age of the caries-free group was 55.48 7.57 months and that of caries active group was 57.84 6.76 months. The caries-active subjects recorded significantly higher bacterial counts of S. mutans and Lactobacillus compared to the cariesfree subjects. Streptococcus mutans and Lactobacillus showed a negative and highly significant correlation with resting pH (r = - 0.38 and r = - 0.32 value respectively)., Conclusion: The resting pH of saliva in both groups was within normal values. Streptococcus mutans and Lactobacillus counts were significantly inversely correlated to the resting pH value of saliva. Streptococcus mutans and Lactobacillus counts were significantly higher in the caries active group., Contexte: La carie est contrôlée par plusieurs facteurs dont l'exposition à des régimes riches en glucides, la sensibilité des dents et la présence de certaines bactéries de la flore buccale telles que Streptococcus mutans (S. mutans) et Lactobacilli sp.. La déminéralisation des dents se produit lorsque le pH dans la cavité buccale est inférieur au pH critique de 5,5 qui se produit à la suite de la production d'acide par les bactéries acidurogènes dans la flore buccale lorsqu'elles décomposent les sucres (substrat) pour l'énergie., But Et Objectif: L'objectif de cette étude était de déterminer le nombre de Streptococcus mutans et de Lactobacillus et leur association avec le pH au repos de la salive et des caries dentaires chez les enfants d'âge préscolaire à Lagos., Matériel Et Méthodes: Cinquante enfants d'âge préscolaire avec et sans caries ont été recrutés respectivement à la clinique dentaire et à l'école primaire du personnel de l'hôpital universitaire de Lagos, Idiaraba. La salive a été recueillie dans un milieu au thioglycolate. Le pH au repos de la salive a été mesuré immédiatement en clinique avec un pHmètre (Jenway pH meter, PHS 25).Au laboratoire, les échantillons ont été striés sur gélose bacitracine Mitis salivarius (MSB) et gélose Rogosa pour S. mutans et Lactobacillus respectivement et incubés en anaérobiose pendant 48 heures à 37°C. Des tests biochimiques et des caractéristiques morphologiques des colonies ont été utilisés pour identifier S. mutans et Lactobacillus., Résultats: Les enfants étaient âgés de 45 à 71 mois avec un âge moyen de 56,66 ± 7,17 mois. L'âge moyen du groupe sans carie était de 55,48 ± 7,57 mois et celui du groupe avec carie active était de 57,84 ± 6,76 mois. Les sujets actifs carieux ont enregistré un nombre de bactéries significativement plus élevé de S. mutans et Lactobacillus par rapport aux sujets sans caries. Streptococcus mutans et Lactobacillus ont montré une corrélation négative et hautement significative avec la valeur du pH au repos (r = - 0.38 et r = - 0.32 respectivement) ., Conclusion: Le pH au repos de la salive dans les deux groupes était dans les valeurs normales. Les numérations de Streptococcus mutans et de Lactobacillus étaient significativement inversement corrélées à la valeur du pH de la salive au repos. Les numérations de Streptococcus mutans et de Lactobacillus étaient significativement plus élevées dans le groupe actif carieux., Mots-Clés: Numération bactérienne, Streptococcus mutans, Lactobacillus, pH delasalive,Enfants d'âgepréscolaire., Competing Interests: The Authors declare that no competing interest exists, (Copyright © 2023 by West African Journal of Medicine.)

Background: The antibacterial and antioxidant properties of the essential oils (EOs) of unripe and ripe fruits of Dennettia tripetala and their potential for the management of infectious and oxidative-stress diseases were investigated in-vitro in this study. Method: Essential oil obtained from the fruit in Clevenger modified apparatus, was characterized by high resolution GC-MS, while antioxidant and antibacterial properties were tested by spectrophotometric and agar diffusion methods respectively. Results: The EO demonstrated strong antibacterial properties when subjected to multi --drug resistant bacterial strains: Enterococcus faecium (ATCC19434), Escherichia coli (ATCC 700728), Staphylococcus aureus (NCINB 50080), Listeria ivanovii (ATCC 19119), Enterobacter cloacae (ATCC13047) and four previously confirmed multi resistant bacterial isolates from our laboratory stock culture. The unripe fruit oil (UFO) demonstrated greater activity than the ripe fruit oil (RFO) against most of the tested bacteria with minimum inhibition concentrations (MIC) ranging between 0.05-0.20 mg/mL while that of the ripe fruit oil (RFO) ranged from 0.10-0.20 mg/mL. The IC50 for RFO (0.62 ± 0.12 mg/mL) showed that it has higher antioxidant strength than UFO and vitamin C (0.87 ± 0.23 and 3.39 ± 0.12 mg/mL) but a lower activity compared to β-carotene (0.32 ± 0.22 mg/mL) in scavenging 2, 2-diphenyl-1-picrylhydrazyl radicals (DPPH•). The EOs also demonstrated strong ability in scavenging three other different radicals (ABTS, lipid peroxide and nitric oxide radicals) in concentration dependant -manner. Conclusion: Findings from this study suggest that apart from the local uses of the plant extracts, the EO has strong bioactive compounds, noteworthy antibacterial, antiradical properties and may be good candidates in the search for lead constituents for the synthesis of novel potent antibiotics. [ABSTRACT FROM AUTHOR]

This study investigated the occurrence of Escherichia coli O157:H7 and Salmonella spp. and their antimicrobial susceptibility from ducks and indigenous chickens in major live-bird markets at Ibadan, Oyo State, Nigeria. Thirty-one cloacae samples were each collected from both ducks and indigenous chickens in three different sample locations for a total of 186 cloacae swab samples. Isolation of Escherichia coli (E. coli) was done using MacConkey agar and Sorbitol MacConkey agar selective for E. coli O157:H7, while serological latex agglutination test kit was used to confirm isolates. Rappaport Vassiliadis and Xylose Lysine Deoxycholate agar were used for Salmonella spp. Antibiotic susceptibility was determined using the disc diffusion method and interpreted using the CLSI 2020 standards. Data were analyzed using descriptive statistics and Fisher's exact test (p ≤ 0.05). Escherichia coli O157:H7 was confirmed in 31 samples (16.7%). E. coli isolates showed high resistance (90.3-93.5%) to cefuroxime, cefixime, ceftazidime, and amoxicillin, while they were highly susceptible to ofloxacin (96.8%) and gentamycin (80.7%). Salmonella was confirmed in 24 samples (12.9%). Salmonella showed 100% resistance to cefuroxime, cefixime ceftazidime, and amoxicillin, but was highly susceptible to gentamycin (91.7%) and nitrofurantoin (66.7%). No statistically significant association (p<0.05) was observed between the occurrence of E. coli O157 and Salmonella within the three live-bird markets. This study reveals that E. coli and Salmonella spp. occur in ducks and indigenous chickens from major live bird markets in Ibadan, Oyo state with antimicrobial susceptibility. Findings from this study underscores the need for further studies on these pathogenic organisms from ducks in Nigeria because there is paucity of data on this species of poultry that may serve as reservoir for these zoonotic organisms.

Yeast diversity during fermentation of grated cassava for gari production in Nigeria was studied using culture independent methods based on Eukarya18S rDNA and the PCR-Denaturing Gradient Gel Electrophoresis (PCR-DGGE). DNA extracted directly from the grated cassava at different fermentation time regimes, as well as bulk cells generated from different viable count agar plates were used as template for amplification of 18S rDNA gene in a PCR experiment. Analysis of the 18S rDNA gene by sequencing of the PCR-DGGE band fragments revealed closest relative of Issatchenkia scutulata, Candida rugopelliculosa, Candida maritime, Zygosaccharomyces rouxii and Galactomyces geotricum as member of yeast community involved with the fermentation. PCR-DGGE can be useful for yeast in situ profiling during fermentation; this will contribute to safety of traditional fermented foods and optimization during large scale production of gari. [ABSTRACT FROM AUTHOR]

This study reports the survey of the level of efficacy of some brands of the antibiotics sold in Calabar, Nigeria. This survey was carried out using the agar diffusion technique. Ten brands of 5 different antibiotics were bought from different pharmacy shops in Calabar metropolis and tested against Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus pyogenes to determine their efficacies. The test antibiotics were 2 brands each of ampicillin, chloramphenicol, erythromycin, septrin and vancomycin. This survey measured the ability of these antibiotics to inhibit bacterial growth in-vitro. The potency or activity per milligram of a chemotherapeutic agent is expressed on the basis of the lowest concentration of minimal inhibitory concentrations (MICs) or higher zones of inhibition. From the results, the overall mean zones of inhibition for the test organisms ranged from 20.2 mm - 33.3 mm, with 21.9 mm for E. coli, 26.4 mm for K. pneumoniae, 20.2 mm for P. aeruginosa, 33.3 mm for S. aureus, and 21.7 mm for S. pyogenes. Our study showed that there were no significant differences (P > 0.05) between the mean zones of inhibition of the test antibiotics and standard controls tested against the test organisms except for P. aeruginosa and K. pneumoniae. The 2 brands of ampicillin and erythromycin were significantly (P = 0.027; P = 0.038) less effective against P. aeruginosa compared to the standard controls while for K. pneumoniae, the 2 brands of chlorampenicol and erythromycin were significantly (P = 0.049; P = 0.057) less effective compared to the standard controls. The results showed that the level of potency of these antibiotics vary according to the different manufacturers. Indeed, the findings of this survey confirm that some of the brands of antibiotics (ampicillin, chloramphenicol and erythromycin) sold in Nigeria may be fake or adulterated and do not contain the acclaimed quantity of active ingredients, which is a reflection of what goes on in many developing countries, in particular, in sub-Saharan Africa. [ABSTRACT FROM AUTHOR]

This study reports the microbiological quality of seafood processors and water used in two different seafood processing plants. Samples of water were collected and palms of seafood processors in two different processing plants were swabbed and microbiologically analyzed for the presence of microorganisms. Total plate counts and enterobacteriaceae counts were enumerated using Plate Count Agar (PCA) and Eosin Methylene Blue (EMB) Agar respectively. Isolates were characterized from the samples on PCA with percentage of occurrence of different microorganisms characterized. All palms sampled haboured Bacillus sp. [8(32.0%)] and Staphylococcus sp. [6(24.0%)] which were most frequently isolated. These pathogens were also present in all the palm swab of all the frozen seafood processors/handlers and water used by them, followed by Enterobacter sp. [4(16.0%)] and Flavobacterium sp. [3(12.0%)]. Micrococcus sp. [1(4.0%)], Pseudomonas aeroginosa [1(4.0%)], Streptococcus faecalis [1(4.0%)] and Escherichia coli [1(4.0%)] were only isolated from water samples and none from the swab samples. Seafood processors may be sources of microbial chance inoculation, microbial food poison, food intoxication and food spoilage hence, food processors may be counter productive by being responsible for public health hazard and loss of revenue. The findings of this study indicated that using current WHO/FAO guidelines and standards for foods and water, none of the food processors were within acceptable standards, also only 40% of the water samples were acceptable and 60% were unsatisfactory quality. Unsatisfactory results were due to high colony counts, presence of determinants/index of food and water quality- E. coli, Streptococcus faecalis, and S. auerus. There were significant correlations between bacteriological quality and food hygiene training, and waste product management polices. This study suggests that there is need to improve on hygienic practices in public food service outlets in order to obtain relatively safe processed seafood products for human consumption. [ABSTRACT FROM AUTHOR]

Objective: The present study was carried out to determine the most potent available antimicrobials in the treatment of pathogens of reproductive health importance in Nigeria. Material and methods: Using the agar disc-diffusion and modified agar well-diffusion methods, bacterial and fungal pathogens obtained from clinical specimens of female patients presenting at the University College Hospital, Nigeria were screened in vitro against the most commonly-available routine antibiotics and antifungals in Nigeria. Results: The Gram-negative bacterial pathogens were mostly susceptible to azthromycin, fortum, ceftriazone, ofloxacin, perfloxacin, rocephine and zinnat. The Gram-positive bacterial pathogens were mostly susceptible to ceftriazone, perfloxacin, rocephine, ciprofloxacin, azthromycin, zinnat and erythromycin. High overall phenotypic antibiotic resistance was displayed towards ampicillin, septrin, gentamicin, penicillin, streptomycin and tetracycline. The Gram-positive bacterial pathogens were mostly resistant to ampicillin (66.7 - 94.4%); streptomycin (53.8 - 100%); chloramphenicol (77.8 - 100%), penicillin (72.2 - 100%) and septrin (50.0 - 91.4%). The most generally resisted antibiotics among the Gram-negative bacteria were gentamicin (40.0 - 75.0%); tetracycline (57.1 - 100%); ampicillin (75.5 - 100%); streptomycin (79.4 - 100%); penicillin (91.4 - 100%) and septrin (76.5 - 91.4%). The Candida species were mostly resistant to all the test antifungals except Candida albicans. Conclusion: The findings of this study reported that the old-generation antibiotics were mostly resisted by the bacterial pathogens implicated in RHI, indicating their non-suitability as regimen for treatment of reproductive health infections. However, these antibiotics are the most abused in Nigeria, especially through self-medications because they are the most available and affordable. [ABSTRACT FROM AUTHOR]

Some Nigerian medicinal plants are popular among traditional producers of phytotherapies in the treatment of sexually related infections. For this study we used modified agar disk, agar spot and agar well-diffusion methods, preparations of simulated crude aqueous and ethanolic extracts of 11 traditionally used medicinal plants for in vitro antimicrobial activities against seventy five strains of Candida species associated with Candida vaginitis and 37 vaginal Lactobacillus species. Candida pseudotropicalis (Castell.) Basgal were minimally inhibited by the plant extracts, while the rate of inhibition of other Candida strains by the ethanolic extracts of the plants were, Ageratum conyzoides L. (44.4 - 66.7%), Anthocleista djalonensis A. Chev. (57.1 - 66.7%), Senna alata (L.) Roxb. (44.4 - 75.0%) Ficus exasperata Vahl. (44.4 - 62.5%), Gliricidia sepium Kunth ex Steud. (64.3%-75.0%) Chromolaena odorata (L.) R.M. King & H. Rob.(57.1%-62.5%) and Rauwolfia vomitoria Afzel. (62.5%). Apart from Aspilia africana (Pers.) C.D. Adams (24.3%) and Ageratum conyzoides L. (35.1%), very low in vitro inhibitory activities of between 5.4% and 16.2% were produced by the medicinal plants against the vaginal Lactobacillus species indicating their ethnophytotherapeutic safety. [ABSTRACT FROM AUTHOR]

Five yeast isolates obtained from cashew tree flowers in Nigeria resembled Cryptococcus neoformans phenotypically by producing brown pigmented colonies on niger seed agar, expressing a capsule, and being able to grow at 37°C. However, rRNA gene sequences, including the 18S rRNA gene, the D1/D2 domains of the 26S rRNA gene and the ITS1+2 regions, suggested that these yeasts form a basal lineage within the Trichosporonales ( Tremellomycetidae, Hymenomycetes, Basidiomycota, Fungi). Since the isolates could not be identified with any known genus and species within the Trichosporonales, we describe them as Cryptotrichosporon anacardii gen. et sp. nov. with CBS 9551T (=NRRL Y-27671) as the type strain. The taxonomic conflict between phenetic and molecular classification schemes within this group of fungi is discussed, and is resolved in favor of the latter. [ABSTRACT FROM AUTHOR]

Background: Methicillin-resistant Staphylococcus aureus is a global public health challenge and there is a continuous increase in community-acquired infections among people in different geographical location. We sought the distribution and antibiotics pattern of community-acquired methicillin-resistant Staphylococcus isolates among apparently healthy residents of Ibadan, Southwestern Nigeria., Methods: Seven hundred (700) healthy volunteers residing in Ibadan metropolis, Nigeria, were enrolled in this study. Isolates from the nasal swabs were aseptically collected and characterized using standard and established microbiological methods, which included growth and fermentation on mannitol salt agar, colonial morphology, Gram-staining reaction, Microbact™ 12S identification kit and confirmed with 16SrRNA. After identification of the isolates, antimicrobial susceptibility test was performed on Mueller-Hinton agar by modified Kirby-Bauer disc diffusion method and the presence of mecA and nuc genes were detected via polymerase chain reaction assay., Results: Prevalence of Staphylococcus aureus nasal carriage and Methicillin-resistant Staphylococcus in this study was 31.9% and 9.43% respectively. The residents of Ibadan North local government area (Fisher's Exact = 1.8962, P = .028) and Egbeda local government area (Fisher's Exact = 2.7222, P = .006) are likely to carry Methicillin-resistant Staphylococcus than any other local government area in Ibadan, Nigeria. The antimicrobial resistance patterns of the isolates revealed high resistance to Oxacillin (96.9%). Most of the isolates were sensitive to vancomycin (92.4%). Polymerase chain reaction analysis showed that mecA gene was present in all 66 (100%) Methicillin-resistant Staphylococcus aureus isolates. Male-gender (ϰ 2  = 8.849, P = .003), Adults; 40-50 years old (ϰ 2  = 9.842, P = .002), low educational background (ϰ 2  = 36.817, P ˂ .001), recent hospital visitation (ϰ 2  = 8.693, P = .003) are some of the factors that are observed in this study to be associated with Methicillin-resistant Staphylococcus infection., Conclusion: Our findings revealed the relatively high frequency of nasal carriers of Methicillin-resistant Staphylococcus aureus among the apparently healthy residents of the studied area and the advent of multidrug resistance among these isolates. Our study also supports previous findings on male-gender and low educational background as risk factors of S. aureus carriage. The need for rational chemotherapy, routine detection and regular surveillance of Methicillin-resistant Staphylococcus to limit its spread and reduce treatment failures is important., (© 2021. The Author(s), under exclusive license to Springer Nature Switzerland AG.)