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Molecules (Basel, Switzerland) Sep 2022Salvianic acid A (SAA), as the main bioactive component of the traditional Chinese herb , has important application value in the treatment of cardiovascular diseases. In...
Salvianic acid A (SAA), as the main bioactive component of the traditional Chinese herb , has important application value in the treatment of cardiovascular diseases. In this study, a two-step bioprocess for the preparation of SAA from l-DOPA was developed. In the first step, l-DOPA was transformed to 3,4-dihydroxyphenylalanine (DHPPA) using engineered cells expressing membrane-bound L-amino acid deaminase from After that, the unpurified DHPPA was directly converted into SAA by permeabilized recombinant cells co-expressing d-lactate dehydrogenase from and formate dehydrogenase from N10. Under optimized conditions, 48.3 mM of SAA could be prepared from 50 mM of l-DOPA, with a yield of 96.6%. Therefore, the bioprocess developed here was not only environmentally friendly, but also exhibited excellent production efficiency and, thus, is promising for industrial SAA production.
Topics: Biocatalysis; Escherichia coli; Formate Dehydrogenases; Levodopa; Phenylpyruvic Acids
PubMed: 36144828
DOI: 10.3390/molecules27186088 -
TheScientificWorldJournal 2023In this study, previously isolated from Lake Mariout (Alexandria, Egypt) was cultivated in the laboratory using a medium for pharmaceutical grade , named as Amara and...
In this study, previously isolated from Lake Mariout (Alexandria, Egypt) was cultivated in the laboratory using a medium for pharmaceutical grade , named as Amara and Steinbüchel medium. Hot water extract of the Egyptian was prepared by autoclaving dried biomass in distilled water at 121°C for 15 min. This algal water extract was analyzed by GC-MS to evaluate its volatile compounds and fatty acids composition. The antimicrobial activity of phycobiliprotein extract from using phosphate buffer was evaluated against thirteen microbial strains (two Gram-positive bacteria, eight Gram-negative bacteria, one yeast, and two filamentous fungi). The major components of fatty acids in the hot extract of Egyptian were hexadecanoic acid (palmitic acid, 55.19%) and octadecanoic acid (stearic acid, 27.14%). The main constituents of its volatile compounds were acetic acid (43.33%) and oxalic acid (47.98%). The most potent antimicrobial effect of phycobiliprotein extract was obtained against two Gram-negative bacteria and , filamentous fungus , and the pathogenic yeast (all of which showed MIC values of 58.1 g/ml). and come second in their susceptibility to the phycobiliprotein extract from and and are the least in susceptibility, with MIC values of 116.2 and 232.5 g/ml, respectively, while phycobiliprotein extract has no antibacterial effect on methicillin-resistant as well as susceptible , , , and . These findings confirmed the nutritional value of Egyptian isolated from Lake Mariout and suggest the potential use of this strain as an ingredient in the cooking of some foods to increase the level of stearic acid and palmitic acid. Moreover, its effective antibacterial activities against some important and highly resistant to antibiotics bacterial pathogens in addition to its antifungal effects recommend the therapeutic use of its biomass.
Topics: Egypt; Spirulina; Fatty Acids; Lakes; Antifungal Agents; Anti-Bacterial Agents; Gram-Negative Bacteria; Yeasts; Candida albicans; Water; Stearic Acids; Palmitic Acids; Microbial Sensitivity Tests
PubMed: 36890980
DOI: 10.1155/2023/9919814 -
Drug Design, Development and Therapy 2019In this study, 2 symmetrical and 3 unsymmetrical thioureas were synthesized to evaluate their antioxidant, antibacterial, antidiabetic, and anticholinesterase potentials.
BACKGROUND
In this study, 2 symmetrical and 3 unsymmetrical thioureas were synthesized to evaluate their antioxidant, antibacterial, antidiabetic, and anticholinesterase potentials.
METHODS
The symmetrical thioureas were synthesized in aqueous media in the presence of sunlight, using amines and CS as starting material. The unsymmetrical thioureas were synthesized using amines as a nucleophile to attack the phenyl isothiocyanate (electrophile). The structures of synthesized compounds were confirmed through H NMR. The antioxidant potential was determined using DPPH and ABTS assays. The inhibition of glucose-6-phosphatase, alpha amylase, and alpha glucosidase by synthesized compounds was used as an indication of antidiabetic potential. Anticholinesterase potential was determined from the inhibition of acetylcholinesterase and butyrylcholinesterase by the synthesized compounds.
RESULTS
The highest inhibition of glucose-6-phosphatase was shown by compound (03.12 mg of phosphate released). Alpha amylase was most potently inhibited by compound with IC value of 62 µg/mL while alpha glucosidase by compound with IC value of 75 µg/mL. The enzymes, acetylcholinesterase, and butyrylcholinesterase were potently inhibited by compound with IC of 63 µg/mL and 80 µg/mL respectively. Against DPPH free radical, compound was more potent (IC = 64 µg/mL) while ABTS was more potently scavenged by compound with IC of 66 µg/mL. The antibacterial spectrum of synthesized compounds was determined against Gram-positive bacteria () and Gram-negative bacteria ( and ). Compound and compound showed maximum activity against with MIC values of 4.02 and 4.04 µg/mL respectively. Against , compound was more active (MIC = 8.94 µg/mL) while against . , compound was more potent with MIC of 4.03 µg/mL.
CONCLUSION
From the results, it was concluded that these compounds could be used as antibacterial, antioxidant, and antidiabetic agents. However, further in vivo studies are needed to determine the toxicological effect of these compounds in living bodies. The compounds also have potential to treat neurodegenerative diseases.
Topics: Acetylcholinesterase; Agrobacterium; Anti-Bacterial Agents; Antioxidants; Benzothiazoles; Biphenyl Compounds; Butyrylcholinesterase; Cholinesterase Inhibitors; Humans; Microbial Sensitivity Tests; Molecular Structure; Picrates; Proteus vulgaris; Staphylococcus aureus; Sulfonic Acids; Thiourea
PubMed: 31631973
DOI: 10.2147/DDDT.S225311 -
The EMBO Journal Aug 2022CodB is a cytosine transporter from the Nucleobase-Cation-Symport-1 (NCS1) transporter family, a member of the widespread LeuT superfamily. Previous experiments with the...
CodB is a cytosine transporter from the Nucleobase-Cation-Symport-1 (NCS1) transporter family, a member of the widespread LeuT superfamily. Previous experiments with the nosocomial pathogen Pseudomonas aeruginosa have shown CodB as also important for the uptake of 5-fluorocytosine, which has been suggested as a novel drug to combat antimicrobial resistance by suppressing virulence. Here we solve the crystal structure of CodB from Proteus vulgaris, at 2.4 Å resolution in complex with cytosine. We show that CodB carries out the sodium-dependent uptake of cytosine and can bind 5-fluorocytosine. Comparison of the substrate-bound structures of CodB and the hydantoin transporter Mhp1, the only other NCS1 family member for which the structure is known, highlight the importance of the hydrogen bonds that the substrates make with the main chain at the breakpoint in the discontinuous helix, TM6. In contrast to other LeuT superfamily members, neither CodB nor Mhp1 makes specific interactions with residues on TM1. Comparison of the structures provides insight into the intricate mechanisms of how these proteins transport substrates across the plasma membrane.
Topics: Biological Transport; Cations; Cytosine; Flucytosine; Membrane Transport Proteins; Symporters
PubMed: 35775318
DOI: 10.15252/embj.2021110527 -
Molecules (Basel, Switzerland) Mar 2022Growing data suggest that , an endophytic fungus, is a rich source of natural compounds with a wide range of biological properties. This study aimed to examine the...
Growing data suggest that , an endophytic fungus, is a rich source of natural compounds with a wide range of biological properties. This study aimed to examine the antimicrobial and antibiofilm capabilities of the -derived endophyte against a set of pathogenic bacteria and fungi. The endophytic fungus sp. AP5 was isolated from the leaves of . The chemical profile of the fungal crude extract was identified by spectroscopic analysis using LC-HRESIMS. The fungal-derived extract was evaluated for its antimicrobial activity towards a set of pathogenic bacterial and fungal strains including , , , sp., , and . Moreover, antibiofilm activity toward four resistant biofilm-forming bacteria was also evaluated. Additionally, a neural-networking pharmacophore-based visual screening predicted the most probable bioactive compounds in the obtained extract. The AP5-EtOAc extract was found to have potent antibacterial activities against , , and sp., while it exhibited low antibacterial activity toward and and displayed anticandidal activity. The AP5-EtOAc extract had significant antibiofilm activity in followed by The active metabolites' antifungal and/or antibacterial activities may be due to targeting the fungal CYP 51 and/or the bacterial Gyr-B.
Topics: Anti-Bacterial Agents; Anti-Infective Agents; Aspergillus niger; Biofilms; Candida albicans; Escherichia coli; Fungi; Microbial Sensitivity Tests; Staphylococcus aureus
PubMed: 35268806
DOI: 10.3390/molecules27051704 -
Pathogens (Basel, Switzerland) Jul 2021This study investigated the spectrum of bacteria infecting the ulcers of individuals with diabetes at the Korle Bu Teaching Hospital in Accra, Ghana, focusing on () and...
AIM
This study investigated the spectrum of bacteria infecting the ulcers of individuals with diabetes at the Korle Bu Teaching Hospital in Accra, Ghana, focusing on () and methicillin-resistant (MRSA), with respect to their prevalence, factors predisposing to their infection of the ulcers, and antimicrobial resistance patterns.
METHODOLOGY
This cross-sectional study was conducted at The Ulcer Clinic, Department of Surgery, Korle Bu Teaching Hospital, involving 100 diabetic foot ulcer patients. The ulcer of each study participant was swabbed and cultured bacteriologically, following standard procedures. Antimicrobial susceptibility testing was done for all isolated, using the Kirby-Bauer method.
RESULTS
In total, 96% of the participants had their ulcers infected-32.3% ( = 31) of these had their ulcers infected with one bacterium, 47.9% ( = 46) with two bacteria, 18.8% ( = 18) with three bacteria, and 1.0% ( = 1) with four bacteria. The prevalence of and MRSA were 19% and 6%, respectively. The distribution of the other bacteria was as follows: coagulase-negative Staphylococci (CoNS) (54%), (24%), spp. (19%), and (12% each), (11%), (8%), spp. (6%), (5%), and spp. (4%), spp. (2%), and spp. (1%). The resistance rates of decreased across penicillin (100%, = 19), tetracycline (47.4%, = 9), cotrimoxazole (42.1%, = 8), cefoxitin (31.6%, = 6), erythromycin and clindamycin (26.3% each, = 5), norfloxacin and gentamicin (15.8% each, = 3), rifampicin (10.5%, = 2), linezolid (5.3%, = 1), and fusidic acid (0.0%, = 0). The proportion of multidrug resistance was 47.4% ( = 9). Except for foot ulcer infection with coagulase-negative Staphylococci, which was protective of infection of the ulcers ( = 0.029, = 0.001, 95% CI = 0.004-0.231), no predictor of , MRSA, or polymicrobial ulcer infection was identified.
CONCLUSIONS
The prevalence of and MRSA infection of the diabetic foot ulcers were high, but lower than those of the predominant infector, coagulase-negative Staphylococci and the next highest infecting agent, . Diabetic foot ulcers' infection with coagulase-negative Staphylococci protected against their infection with . The prevalence of multidrug resistance was high, highlighting the need to further intensify antimicrobial stewardship programmes.
PubMed: 34451401
DOI: 10.3390/pathogens10080937 -
Frontiers in Endocrinology 2023Diabetic foot is one of the most significant complications in individuals with diabetes and is closely associated with lower limb amputation. The antibiotic...
BACKGROUND
Diabetic foot is one of the most significant complications in individuals with diabetes and is closely associated with lower limb amputation. The antibiotic susceptibility patterns of these bacterial isolates play a critical role in guiding effective treatment strategies We aimed to determine the most common bacterial agents causing diabetic foot infections in a tertiary-care hospital in Peru.
METHODS
Clinical and microbiological data were collected from 181 patients diagnosed with diabetic foot infections and positive microbiological culture results. All the samples were analyzed with the Vitek 2 compact system and the cut-off points were defined with the CLSI M100 guide. The data were segregated based on mono-microbial or poly-microbial cultures, bacterial types, and antibiotic susceptibility profiles.
RESULTS
A total of 32 bacterial species were identified, predominantly Gram-negative (63%). The most frequent bacterial agents isolated were (19.9%), (12.2%), (8.3%), and (6.6%). These bacteria commonly exhibited resistance to Ampicillin, Ciprofloxacin, Levofloxacin, Trimethoprim-sulfamethoxazole, and Cefuroxime. showed the highest antibiotic resistance (19 antibiotics), while Gentamicin, Tobramycin, and Levofloxacin demonstrated the highest sensitivity against the most prevalent bacteria. Gram-negative bacteria also exhibited notable antibiotic-susceptibility to Meropenem, Piperacillin/tazobactam, and Amikacin. Regarding the presence of Extended-Spectrum Beta-Lactamase, 54 isolates tested positive, with 35 (64.8%) and 14 (42.4%) of these being .
CONCLUSIONS
Bacterial agents causing diabetic foot infections pose a constant concern, particularly due to the increasing antibiotic resistance observed. This difficulty in treating the condition contributes to a higher risk of amputation and mortality. Further research on bacterial susceptibility is necessary to determine appropriate dosages for pharmacological treatment and to prevent the overuse of antibiotics.
Topics: Humans; Diabetic Foot; Cross-Sectional Studies; Peru; Staphylococcus aureus; Escherichia coli; Levofloxacin; Microbial Sensitivity Tests; Anti-Bacterial Agents; Bacteria; Staphylococcal Infections; Drug Resistance, Microbial; Diabetes Mellitus
PubMed: 38116313
DOI: 10.3389/fendo.2023.1267699 -
Infection and Drug Resistance 2021An ear infection is responsible for up to 40% of preventable hearing impairment; one of the reasons for frequent and unwise antibiotic usage, especially in the...
Bacterial Etiologies of Ear Infection and Their Antimicrobial Susceptibility Pattern at the University of Gondar Comprehensive Specialized Hospital, Gondar, Northwest Ethiopia: A Six-Year Retrospective Study.
BACKGROUND
An ear infection is responsible for up to 40% of preventable hearing impairment; one of the reasons for frequent and unwise antibiotic usage, especially in the developing world. Since the incidence of antibiotic resistance is increasing, especially in resource-limited countries, up-to-date knowledge on the susceptibility of ear-discharge isolates to antibiotic is important for better patient treatment. Therefore, this study aimed at determining the bacterial etiologies and their antibiotic susceptibility profiles among patients suspected with ear infections.
METHODS
We collected retrospective data from bacteriological results of ear discharge samples from 2013 to 2018. Sample collection, culture preparation, and bacterial identification were performed using standard microbiological techniques. Antimicrobial susceptibility testing was performed following Clinical and Laboratory Standard Institute (CLSI) guidelines. We extracted and inputted the data using Epi-info version 7 and exported it to SPSS version 20 for analysis.
RESULTS
The overall ear-discharge culture positivity rate was 283/369 (76.7%) (95% CI = 72.4-81.3), with 14/283 (4.95%) mixed infections. (27.9%), spps (20.8%), spps (10%), and spps (8.92%) were the main isolates. High-level resistance rates for tetracycline (77.6%), penicillins (67.2%), erythromycin (52.6%), and co-trimoxazole (52%), and low-level resistance rates for fluoroquinolones (23.3%), aminoglycosides (23.7%), and cephalosporins (29.8%) were observed. More than 45% of isolates, with 50.9% of Gram-negative and 37.3% of Gram-positive, were multidrug-resistant.
CONCLUSION
, and were the leading cause of ear infections. The presence of high number of multidrug-resistant strains calls for the need for periodic and continuous follow-up of antibiotic usage in the study area. Further studies are recommended to explore the types of ear infections, with their etiologic agents and possible risk factors.
PubMed: 34707376
DOI: 10.2147/IDR.S332348 -
Antibiotics (Basel, Switzerland) Mar 2024Worldwide, bacterial resistance is one of the most severe public health problems. Currently, the failure of antibiotics to counteract superbugs highlights the need to...
Worldwide, bacterial resistance is one of the most severe public health problems. Currently, the failure of antibiotics to counteract superbugs highlights the need to search for new molecules with antimicrobial potential to combat them. The objective of this research was to evaluate the antimicrobial activity of BS4 against Gram-negative bacteria. Thirty yeasts and thirty-two isolates were tested following the agar well-diffusion method. Four sp. strains (BS3, BS4, BS17, and BS21) showed antagonistic activity against ATCC 25922 using bacterial culture (BC) and the cell-free supernatant (CFS), where the BS4 strain stood out, showing inhibitory values of 20.50 ± 0.70 mm and 19.67 ± 0.58 mm for BC and CFS, respectively. The sp. BS4 strain can produce antioxidant, non-hemolytic, and antimicrobial metabolites that exhibit activity against several microorganisms such as , , , , , , , sp., , , and . According to the characterization of the supernatant, the metabolites could be proteinaceous. The production of these metabolites is influenced by carbon and nitrogen sources. The most suitable medium to produce antimicrobial metabolites was TSB broth. The one-factor-at-a-time method was used to standardize parameters such as pH, agitation, temperature, carbon source, nitrogen source, and salts, resulting in the best conditions of pH 7, 150 rpm, 28 °C, starch (2.5 g/L), tryptone (20 g/L), and magnesium sulfate (0.2 g/L), respectively. Moreover, the co-culture was an excellent strategy to improve antimicrobial activity, achieving maximum antimicrobial activity with an inhibition zone of 21.85 ± 1.03 mm. These findings position the BS4 strain as a promising candidate for producing bioactive molecules with potential applications in human health.
PubMed: 38666980
DOI: 10.3390/antibiotics13040304 -
Brazilian Journal of Biology = Revista... 2022The gastrointestinal microflora regulates the body's functions and plays an important role in its health. Dysbiosis leads to a number of chronic diseases such as...
The gastrointestinal microflora regulates the body's functions and plays an important role in its health. Dysbiosis leads to a number of chronic diseases such as diabetes, obesity, inflammation, atherosclerosis, etc. However, these diseases can be prevented by using probiotics - living microorganisms that benefit the microflora and, therefore, improve the host organism's health. The most common probiotics include lactic acid bacteria of the Bifidobacterium and Propionibacterium genera. We studied the probiotic properties of the following strains: Bifidobacterium adolescentis АС-1909, Bifidobacterium longum infantis АС-1912, Propionibacterium jensenii В-6085, Propionibacterium freudenreichii В-11921, Propionibacterium thoenii В-6082, and Propionibacterium acidipropionici В-5723. Antimicrobial activity was determined by the 'agar blocks' method against the following test cultures: Escherichia coli ATCC 25922, Salmonella enterica ATCC 14028, Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa B6643, Proteus vulgaris ATCC 63, and Listeria monocytogenes ATCC 7644. Moderate antimicrobial activity against all the test cultures was registered in Bifidobacterium adolescentis АС-1909, Propionibacterium jensenii В-6085, and Propionibacterium thoenii В-6082. Antioxidant activity was determined by the DPPH inhibition method in all the lactic acid strains. Our study indicated that some Propionibacterium and Bifidobacterium strains or, theoretically, their consortia could be used as probiotic cultures in dietary supplements or functional foods to prevent a number of chronic diseases.
Topics: Anti-Infective Agents; Bifidobacterium; Escherichia coli; Gastrointestinal Tract; Probiotics; Propionibacteriaceae; Propionibacterium
PubMed: 35544788
DOI: 10.1590/1519-6984.256945