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1.
BMC Microbiol ; 24(1): 148, 2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38678188

RESUMEN

BACKGROUND: Urinary tract infections, a prevalent global infectious disease, are clinical issues not well studied in HIV-positive individuals. UTIs have become a global drug resistance issue, but the prevalence and antibiotic susceptibility patterns of UTI-causing bacteria among HIV patients in Tigray, Ethiopia, are poorly understood. This study aims to identify the prevalence of UTI-causing bacteria, their antibiotic susceptibility patterns, and associated risk factors in HIV patients attending ART clinics at Mekelle General Hospital and Ayder Comprehensive Specialized Hospital in Tigray, Northern Ethiopia. METHOD: Clean-catch midstream urine samples (10-15 mL) were collected from HIV patients who are attending ART clinics at Mekelle General Hospital and Ayder Comprehensive Specialized Hospital. Samples were analyzed based on standard microbiological protocols using cysteine-lactose electrolyte deficient (CLED) agar. Pure colonies of bacterial isolates were obtained by sub-culturing into Mac-Conkey, Manitol Salt agar and blood agar plates. The bacterial isolates were then identified using macroscopic, microscopic, biochemical, and Gram staining methods. Gram-negative bacteria were identified using biochemical tests like triple sugar iron agar, Simon's citrate agar, lysine iron agar, urea, motility test, and indol test, whereas Gram-positive isolates were identified using catalase and coagulase tests. The Kirby-Bauer disk diffusion technique was used to analyze the antimicrobial susceptibility pattern of bacterial isolates. Data was analyzed using SPSS version 25.0. RESULTS: Among the 224 patients, 28 (12.5%) of them had been infected by UTIs-causing bacteria. E. coli was the dominant bacterium (16 (57%)) followed by K. pneumoniae (4 (14%)), and S. aureus (3 (11%)). Of the total bacterial isolates, 22 (78.6%) of them developed multi-drug resistance. All Gram-positive (100%) and 75% of Gram-negative bacterial isolates were found to be resistant to two or more drugs. Patients with a history of UTIs, and with CD4 count < 200 cells/ mm3, were more likely to have significant bacteriuria. Compared to male patients, female patients were more affected by the UTIs-causing bacteria. More than 93% of the UTIs-causing bacterial isolates were susceptible to nitrofurantoin, ceftriaxone, ciprofloxacin, and gentamycin; whereas they are highly resistant to ampicillin (96%), cotrimoxazole (82%) and tetracycline (71%). CONCLUSIONS: Most of the bacterial isolates were highly resistant to ampicillin, cotrimoxazole, and tetracycline. Female patients were more affected by the UTIs causing bacteria. The highest prevalence (12.5%) of UTIs in HIV patients needs special attention for better management and monitoring. Previous UTI history and immune suppression are predictors of UTIs, highlighting the need for intervention measures involving molecular studies to identify resistant bacteria genes and promote patient immune reconstitution.


Asunto(s)
Antibacterianos , Infecciones por VIH , Pruebas de Sensibilidad Microbiana , Infecciones Urinarias , Humanos , Etiopía/epidemiología , Infecciones Urinarias/microbiología , Infecciones Urinarias/epidemiología , Femenino , Adulto , Infecciones por VIH/complicaciones , Masculino , Factores de Riesgo , Antibacterianos/farmacología , Persona de Mediana Edad , Adulto Joven , Prevalencia , Bacterias/efectos de los fármacos , Bacterias/aislamiento & purificación , Bacterias/clasificación , Bacterias/genética , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/aislamiento & purificación , Bacterias Gramnegativas/clasificación , Adolescente , Estudios Transversales
2.
Infect Drug Resist ; 17: 495-505, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38348229

RESUMEN

Background: Campylobacter species are the most predominant bacterial agents to cause diarrhea in under-five children. It poses a serious challenge to public health worldwide with ongoing acquisition of resistance to different antimicrobials with multiple patterns. Thus, this study aimed to determine the prevalence, and antimicrobial resistance of Campylobacter species, and associated factors among under-five children with diarrhea in selected public health facilities. Methods: A cross-sectional study was conducted among under-five children with diarrhea using convenient sampling. Health facilities were selected using a simple random sampling method. The stool samples collected from 214 study participants were transported and processed following standard microbiological protocols. Campylobacter isolates were identified using Gram staining, biochemical test, serological test, and aerobic growth at 25°C. Antimicrobial susceptibility profiles of isolates were performed using the Kirby-Bauer method. Data were analyzed using SPSS ver. 25.0. Association between variables was assessed using Chi-square test and Logistic regression, with P ≤ 0.05. Results: The subject's mean age was 31.3 (±3.9) months. Of the 214 samples cultured, 14 (6.5%) of them were positive for Campylobacter species with 95% CI (3.3-10.3). Out of the isolated species, 12 (85.7%) were Campylobacter jejuni /Campylobacter coli and 2 (14.3%) were other Campylobacter species. Bottle feeding and history of direct contact to domestic animals were associated with Campylobacter species (AOR=5.13, CI=1.21-21.6, p=0.026 and AOR=4.93, CI=1.33-18.17, P=0.016), respectively. Campylobacter isolates were highly resistant to ciprofloxacin 5 (35.7%), and tetracycline 3 (21.4%). Conclusion: A higher incidence of Campylobacter species was obtained in children who were bottle-fed and who had a history of direct contact with domestic animals. The isolates were highly resistant to ciprofloxacin and tetracycline. These findings indicate that special attention is needed for better management of Campylobacter drug resistance in under-five children. To enhance and support our current findings, further research using molecular techniques is needed to identify the resistant and virulent genes of the bacterial isolates.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38318096

RESUMEN

Objective: This study aims to investigate the bacterial biofilm-inhibitory effect of mushroom extracts. Methods: Mushrooms were collected from Arabuko-Sokoke and Kakamega forests and identified using morphological and molecular approaches. Auricularia auricula-judae, Microporus xanthopus, Termitomyces umkowaani, Trametes elegans, and Trametes versicolor were extracted by chloroform, 70% ethanol, and hot water. Extracts were tested against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus (ATCC25923). Data were analyzed using SPSS ver. 20.0. Results: Chloroform, 70% ethanol, and hot water extracts of A. auricula-judae (50 µg/mL) showed statistically significant antibiofilm activities against P. aeruginosa, E. coli, and S. aureus (p ≤ 0.05). M. xanthopus extracts (250 µg/mL) revealed significantly significant antibiofilm activities against each test bacterium (p ≤ 0.05). All extracts of T. umkowaani (250 µg/mL) exhibited statistically significant antibiofilm activities against S. aureus only (p ≤ 0.05). Chloroform extract of T. elegans (250 µg/mL) showed the best antibiofilm activity (69.75 ± 0.01%) against S. aureus. All T. versicolor extracts (250 µg/mL) indicated the best antibiofilm activities against S. aureus. Conclusions: Being the first study of its kind to be conducted in Kenya, it added a novel concept to the body of knowledge already known about medical biotechnology research. It offers a fresh understanding of the various varieties of mushrooms found in Kenya, their potential biological function in the production of drugs, particularly those that combat drug resistance, and perhaps even a peek at their bioactive elements. Wild mushrooms, a hidden gem, might help to reopen the pipeline of new antibiotics that have been on the decline. However, further research is required to determine the potential mechanism(s) of action of the extracts that are in charge of the apparent antibiofilm activity.

4.
Int J Anal Chem ; 2023: 5591059, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37920570

RESUMEN

Baobab (Adansonia digitata L) is a large tree species growing in semiarid and arid lowlands of Ethiopia and other places. The plant is valued by natives for its contributions as a cash crop and livelihood tree. Previous studies using samples from different countries have documented their phytochemical profiles and nutritional and health benefits. This study explored the phytochemical constituents and biological activities of fruit pulp extracts of baobab collected from Tekeze Valley, Tigrai, Ethiopia. To this end, qualitative phytochemical screening tests, quantitative phytochemical analyses, and gas chromatography-mass spectrometry (GC-MS) analysis were carried out using aqueous extract. Analyses of antioxidant activities were also conducted with aqueous- and methanol-extracts using of 2,2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide (NO), and hydroxyl (OH) radical scavenging activity assays. The qualitative screening tests showed the presence of flavonoids, phenols, saponins, tannins, and terpenoids. Quantitative analyses of these phytochemicals at 25, 50, and 100 g/mL aqueous extract resulted in 0.0252 to 0.1000% yields. Yields of flavonoids, phenols, and saponins were higher at 50 g/mL extract, while that of tannins and terpenoids were higher at 100 g/mL. GC-MS analysis resulted in 15 predominant compounds including (1,2bis(trimethylsilyl)benzene (13.17%), 2-methyl-7-phenylindole (11.75%), 2-ethylacridine (10.11%), and benz[b]-1,4-oxazepine-4(5H)-thione,2,3-dihydro-2,8-dimethyl (10.11%). Aqueous and methanol extracts showed concentration-dependent antioxidant activities. In all the assays and concentrations, the antioxidant activities of both extracts were lower than that of the ascorbic acid standard. At equal extract concentrations (e.g., 100 and 250 µg/mL), methanol extract had higher antioxidant activities than aqueous extract. The findings can encourage future initiatives towards large-scale research for compiling a complete phytochemical profile of the fruit pulp of the Ethiopian baobab.

5.
Artículo en Inglés | MEDLINE | ID: mdl-37899907

RESUMEN

Objective: This study was aimed at determining the antioxidant, anti-quorum sensing, and in vitro cytotoxic activities of five wild mushroom extracts. Methods: Wild mushrooms of Auricularia auricula-judae, Termitomyces umkowaani, Trametes elegans, Trametes versicolor, and Microporus xanthopus were collected from Arabuko-Sokoke and Kakamega National Forests, in Kenya. Specimens were identified and extracted using chloroform (CHL), 70% ethanol (Eth), and hot water (HW) solvents. Antioxidant and cytotoxic activities of the extracts were determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Vero cell lines, respectively, while anti-quorum sensing activities were tested against Chromobacterium violaceum. All data were compared using relevant descriptive and inferential statistics at a significance level of p ≤ 0.05. Results: A total of 35 wild mushrooms were collected, identified, and classified into 14 genera. Among screened mycochemicals, fatty acids, flavonoids, polyphenols, and saponins were detected at higher concentrations. The highest free radical scavenging activities of A. auricula-judae, T. umkowaani, T. elegans, and T. versicolor were observed in 70% Eth extract with the percentage values of 76.40 ± 0.12%, 68.40 ± 0.01%, 62.40 ± 0.07%, and 66.40 ± 0.04%, respectively, whereas the HW extract of Microporus xanthopus showed free radical scavenging activity at 65.90 ± 0.02%. None of the extracts, at the tested concentrations (up to 1000 µg/mL), had shown cytotoxic activity against the Vero cell line. The HW extract of T. umkowaani and the 70% Eth extract of T. versicolor showed a statistically significant difference in the inhibitory activity of violacein production against C. violaceum at the concentration of 200 µg/mL. Conclusions: The antioxidant activity of wild mushrooms can help to tackle the diseases caused by free radicals. The anti-quorum sensing potential of wild mushrooms could also provide future alternatives to conventional drug therapies cost-effectively. Further detailed chemistry of the bioactive compounds and their possible mechanisms of action responsible for the observed antioxidant and anti-quorum sensing activities are needed.

6.
Int J Anal Chem ; 2023: 6694961, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37781342

RESUMEN

Secondary metabolites are hidden gems in mushrooms. Understanding these secondary metabolites' biological and pharmacological effects can be aided by identifying them. The purpose of this work was to profile the mycochemical components of the extracts of Auricularia auricula judae, Microporus xanthopus, Termitomyces umkowaani, Trametes elegans, and Trametes versicolor to comprehend their biological and pharmacological capabilities. Mushroom samples were collected from Kenya's Arabuko-Sokoke and Kakamega National Reserved Forests and identified using morphological and molecular techniques. Chloroform, 70% ethanol, and hot water solvents were used to extract the mycochemical components. Gas chromatography mass spectrometry (GC-MS) was used to analyze the chloroform, 70% ethanol, and hot water extracts of all the species examined. A total of 51 compounds were isolated from all extracts and classified as carboxylic acids, esters, phenols, fatty acids, alcohol, epoxides, aldehydes, fatty aldehydes, isoprenoid lipids, and steroids. Tetracosamethyl-cyclododecasiloxane (18.90%), oleic acid (72.90%), phenol, 2, 6-bis (1, 1-dimethylethyl)-4-methyl-, and methylcarbamate (26.56%) were all found in high concentrations in A. auricular judae, M. xanthopus, T. umkowaani, T. elegans, and T. versicolor, respectively. Fatty acids make up the majority of the compounds isolated from the T. elegans chloroform extract and the T. umkowaani 70% ethanol extract, respectively. Particularly, these fatty acids play crucial roles in the anti-inflammatory, hypocholesterolemic, anticancer, and antibiofilm formation activities. These bioactive elements indicate that the extracts of five wild mushrooms may be reliable sources of secondary metabolites for therapeutic development. Therefore, additional research is required to comprehend the usefulness of these chemicals in many functional areas and to improve the present understanding of macrofungi.

7.
Heliyon ; 9(6): e17114, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37484381

RESUMEN

Helbat (hl'bət), a fasting semi-liquid condiment, is a popular indigenous traditional fermented product in Tigrai (a.k.a. Tigray), Ethiopia. It is formulated using Vicia faba flour prepared from mildly roasted dry beans. Despite its dietary, nutritional, religious, and cultural significance, the condiment is yet not exposed to scientific study. Hence, this research was carried out to: (a) ascertain the best faba bean variety for preparing high quality Helbat, (b) develop the formulation and preparation protocol of high quality Helbat, (c) determine the effects of fermentation and storage temperature and time on the physicochemical characteristics, proximate and mineral compositions, microbiological properties, and sensory qualities of Helbat, and (d) determine the shelf life of Helbat as the function of storage time and temperature. To this end, three faba bean varieties used in preparing Helbat as well as fermenting and stored Helbat products were studied using standard physicochemical, microbiological, and sensory evaluation procedures. Quantitative data were processed using inferential statistical methods and mean (±SD) values were compared at a priori set p-value of ≤0.05. The study showed that: (a) the best faba bean variety for making high quality Helbat was Megulat; (b) the best Helbat formulation constituted 400 wt units of bean flour, 7 wt units of garlic, 6 wt units of ginger, 5 wt units fenugreek, 5 wt units of corrorima, 8 wt units of red pepper, and 3 wt units of black mustard; (c) the best Helbat formulation was nutritionally rich to supplement fasting consumers with proteins, fats, and minerals; (d) the Helbat formulation remained safe for up to eight weeks while maintaining its attractive sensory qualities when stored at 11-15 °C, and (e) increasing the fermentation and storage times led to changes in its physicochemical properties (i.e., temperature, pH, total titratable acidity, and total soluble solute) and depletion of many nutritionally vital components such as fats, proteins, and minerals. Thus, unless production and storage conditions are somehow modified, Helbat needs to be consumed fresh after three to seven days of fermentation. But further research may be required to make this recommendation conclusively. Exploring into its antioxidant properties and lactic acid bacteria (LAB) may highlight its qualities further.

8.
Heliyon ; 5(8): e02192, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31463386

RESUMEN

BACKGROUND: Biofilms are multicellular communities of microorganisms held together by a self-produced extracellular matrix. The ability of microbes to form biofilm is a universal, ubiquitous, and dynamic process. This dynamic process of biofilms establishes an important strategy to withstand and survive harsh environmental conditions and antimicrobial agents. OBJECTIVE: This review paper aims to give an overview of antibiotic resistance, intervention, and treatment of infections caused by biofilm-forming organisms. Moreover, it can also help to motivate scholars to search for new anti-biofilm strategies and most appropriate methods to tackle the effect of biofilm infections on healthcare services. METHODS: This paper was written by reviewing recent research and review articles which are reporting about the antibiotic resistance, prevention, and treatment of biofilm-producing organisms. CONCLUSION: Bioprospecting for quorum quenching compounds can be an appropriate solution for controlling biofilm infections.

9.
ScientificWorldJournal ; 2019: 7357048, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31427902

RESUMEN

Mushrooms produce a variety of bioactive compounds that are known to have a potential source of antioxidant and antimicrobial properties. Natural antioxidants can protect against free radicals without any side effects. The purpose of this study was to evaluate the antioxidant and antimicrobial activities of Auricularia and Termitomyces extracts. Specimens of Auricularia and Termitomyces spp. were collected from Kakamega National Reserve Forest in Kenya. Specimens were identified, extracted, and screened for their antioxidant and antimicrobial activities using stable free radical DPPH and colorimetric bioassay methods, respectively. The antimicrobial activity of the extracts was tested against Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, MRSA, Candida albicans, and Candida parapsilosis. The maximum scavenging activity of hot water extract of Auricularia spp. was observed at 70.4% with the IC50 value of 40 µg/mL. Of the three extracts of Termitomyces spp., 70% ethanol extract has shown the highest scavenging activity (63%) with the IC50 value of 50 µg/mL. Chloroform and hot water extracts of Auricularia have shown statistically significantly different antifungal activities against C. parapsilosis (df = 2, F = 22.49, p ≤ 0.05). Of all the organisms, S. aureus was highly susceptible to 70% ethanol and hot water extracts of Termitomyces spp. with minimum inhibitory concentration values of 0.67±0.29 mg/mL. S. aureus and E. coli were the most susceptible and resistant bacteria to the hot water extract, respectively. In conclusion, the extracts of Auricularia spp. and Termitomyces spp. have shown promising antimicrobial and antioxidant activities.


Asunto(s)
Agaricales/química , Antibacterianos/farmacología , Antioxidantes/farmacología , Extractos Vegetales/farmacología , Termitomyces/química , Depuradores de Radicales Libres/farmacología , Geografía , Kenia , Pruebas de Sensibilidad Microbiana
10.
Artículo en Inglés | MEDLINE | ID: mdl-30906415

RESUMEN

OBJECTIVE: This study has investigated the antimicrobial activity of extracts of indigenous wild mushrooms against selected organisms. METHODS: Thirty-five (35) indigenous wild mushrooms were collected from Arabuko-Sokoke and Kakamega National Reserve Forests, Kenya. All mushrooms were identified and their contents were extracted and screened for their antimicrobial activities against Escherichia coli (clinical isolate), Klebsiella pneumoniae (ATCC 13883), Pseudomonas aeruginosa (clinical isolate), Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 25923), MRSA (ATCC 33591), Candida albicans (clinical isolate), and Candida parapsilosis (ATCC 90018) using tetrazolium microtiter plate bioassay method. RESULTS: Of the 35 tested mushroom extracts, extracts of three (3) mushrooms, namely, Trametes spp. (Arabuko-Sokoke forest), Trametes, and Microporus spp. (Kakamega forest), have shown promising antimicrobial activities against the tested organisms. The S. aureus (ATCC 25923), P. aeruginosa (ATCC 27853), and Methicillin-Resistant Staphylococcus aureus (MRSA) (ATCC 33591) were the most susceptible to chloroform extract of Trametes spp. collected from Arabuko-Sokoke forest. Of the tested organisms, S. aureus (ATCC 25923) was the most susceptible whereas E. coli was the most resistant organism to the hot water extract of Trametes spp. collected from Arabuko-Sokoke forest. Chloroform extract of Microporus spp. has shown the highest antibacterial activity against S. aureus (ATCC 25923), MRSA (ATCC 33591), and K. pneumoniae (ATCC 13883) but limited activity against E.coli. All extracts of the three wild mushrooms have shown the most antibacterial activities against S. aureus (ATCC 25923). CONCLUSION: The present study has shown that the extracts of the three wild mushrooms have shown promising antimicrobial activities against the tested organisms.

11.
Asian Pac J Trop Biomed ; 3(6): 426-35, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23730554

RESUMEN

OBJECTIVE: To isolate, evaluate and characterize potential antibiotic producing actinomycetes from water and sediments of Lake Tana, Ethiopia. METHODS: A total of 31 strains of actinomycetes were isolated and tested against Gram positive and Gram negative bacterial strains by primary screening. In the primary screening, 11 promising isolates were identified and subjected to solid state and submerged state fermentation methods to produce crude extracts. The fermented biomass was extracted by organic solvent extraction method and tested against bacterial strains by disc and agar well diffusion methods. The isolates were characterized by using morphological, physiological and biochemical methods. RESULTS: The result obtained from agar well diffusion method was better than disc diffusion method. The crude extract showed higher inhibition zone against Gram positive bacteria than Gram negative bacteria. One-way analysis of variance confirmed most of the crude extracts were statistically significant at 95% confidence interval. The minimum inhibitory concentration and minimum bactericidal concentration of crude extracts were 1.65 mg/mL and 3.30 mg/mL against Staphylococcus aureus, and 1.84 mg/mL and 3.80 mg/mL against Escherichia coli respectively. The growth of aerial and substrate mycelium varied in different culture media used. Most of the isolates were able to hydrolysis starch and urea; able to survive at 5% concentration of sodium chloride; optimum temperature for their growth was 30 °C. CONCLUSIONS: The results of the present study revealed that freshwater actinomycetes of Lake Tana appear to have immense potential as a source of antibacterial compounds.


Asunto(s)
Actinobacteria/fisiología , Antibacterianos/farmacología , Sedimentos Geológicos/microbiología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Lagos/microbiología , Actinobacteria/aislamiento & purificación , Antibacterianos/metabolismo , Etiopía , Pruebas de Sensibilidad Microbiana
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