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Insects Mar 2023This study was conducted to assess the bioactive value of honey samples collected from three countries. In total, 150 honey samples from Saudi Arabia (50), Libya (50),...
This study was conducted to assess the bioactive value of honey samples collected from three countries. In total, 150 honey samples from Saudi Arabia (50), Libya (50), and Egypt (50) were collected and compared, based on the results of the melissopalynological analysis, their physicochemical attributes, antioxidant and antimicrobial activities, and biochemical properties, together with their total phenolic and total flavonoid contents. Depending on the geographical origin, we observed different levels of growth suppression for six resistant bacterial strains. The pathogenic microorganisms tested in this study were and There was a strong correlation between the polyphenol and flavonoid contents, as well as significant ( < 0.05) radical scavenging activities. The melissopalynological analysis and physicochemical properties complied with the recommendation of the Gulf and Egyptian Technical Regulations on honey, as well as the Codex Alimentarius of the World Health Organization and the European Union Normative related to honey quality. It was concluded that honey from the three countries has the capacity to suppress pathogenic bacterial growth and has significant radical scavenging activities. Moreover, these findings suggest that honey may be considered as an interesting source of antimicrobial compounds and antioxidants for therapeutical and nutraceutical industries or for food manufacturers.
PubMed: 37103134
DOI: 10.3390/insects14040319 -
International Journal of Systematic and... Apr 2018Two strains of Gram-stain-negative, facultatively anaerobic short-rod bacteria were recovered from two different food samples in Ma'anshan city, Anhui province, China in...
Two strains of Gram-stain-negative, facultatively anaerobic short-rod bacteria were recovered from two different food samples in Ma'anshan city, Anhui province, China in 2008. The bacteria were characterized in a polyphasic taxonomic study that included phenotypic, phylogenetic and genotypic methodologies. Phylogenetic analysis of the 16S rRNA gene demonstrated that the two strains belonged to the genus Proteus and were most similar to Proteus vulgaris ATCC 29905 with a score of 99.7 %. Phylogenetic analysis of the rpoB gene placed the two strains into a cluster with a distinctly interspecies phylogenetic branch that was clearly separated from six type strains of the genus Proteus, with the most closely related species being Proteus mirabilis ATCC 29906. In silico genomic comparisons, including in silico DNA-DNA hybridization (isDDH) and average nucleotide identity (ANI) analysis showed that the representative strain, 08MAS0041, and all six Proteus species share less than 70 % isDDH and have a 95 % ANI cutoff level, supporting the designation of the two strains as a novel species of the genus Proteus. The predominant cellular fatty acids of strain 08MAS0041 were C16 : 0 (24.8 %), C16 : 1ω7c/16 : 1ω6c (16.5 %), C18 : 1ω6c/C18 : 1ω7c (14.5 %), C17 : 0 cyclo (12.6 %) and C16 : 1iso I/C14 : 0 3-OH (10.6 %). The analysis of biochemical, phylogenetic and genomic data confirmed that the two strains were clearly different from all recognized species of the genus Proteus and represent a novel Proteus species, for which the name Proteus alimentorum sp. nov. is proposed. The type strain is 08MAS0041 (=DSM 104685=CGMCC 1.15939).
Topics: Animals; Bacterial Typing Techniques; Base Composition; China; DNA, Bacterial; Fatty Acids; Nephropidae; Nucleic Acid Hybridization; Phylogeny; Proteus; RNA, Ribosomal, 16S; Red Meat; Seafood; Sequence Analysis, DNA; Swine
PubMed: 29509133
DOI: 10.1099/ijsem.0.002689 -
Journal of Infection and Chemotherapy :... Jun 2023A hemin-requiring Proteus vulgaris small-colony variant (SCV) was isolated from a urine culture. This isolate was grown on 5% sheep blood agar but not on modified...
A hemin-requiring Proteus vulgaris small-colony variant (SCV) was isolated from a urine culture. This isolate was grown on 5% sheep blood agar but not on modified Drigalski agar. The single nucleotide substitution was found in the SCV of the hemC gene (c.55C > T), and this substitution caused a nonsense mutation (p.Gln19Ter). Porphyrin test results showed that the biosynthesis of δ-aminolevulinic acid stopped up to porphobilinogen and not pre-uroporphyrinogen due to a mutation in the hemC gene. To our knowledge, this is the first report of hemin-requiring P. vulgaris.
Topics: Animals; Sheep; Hemin; Proteus vulgaris; Agar; Porphyrins; Culture Media
PubMed: 36996937
DOI: 10.1016/j.jiac.2023.03.015 -
Chembiochem : a European Journal of... May 2022The aromatic amino acid l-tryptophan serves as a precursor for many valuable compounds such as neuromodulators, indoleamines and indole alkaloids. In this work,...
The aromatic amino acid l-tryptophan serves as a precursor for many valuable compounds such as neuromodulators, indoleamines and indole alkaloids. In this work, tryptophan biosynthesis was extended by halogenation followed by decarboxylation to the respective tryptamines or cleavage to the respective indoles. Either the tryptophanase genes tnaAs from E. coli and Proteus vulgaris or the aromatic amino acid decarboxylase genes AADCs from Bacillus atrophaeus, Clostridium sporogenes, and Ruminococcus gnavus were expressed in Corynebacterium glutamicum strains producing (halogenated) tryptophan. Regarding indoles, final titers of 16 mg L 7-Cl-indole and 23 mg L 7-Br-indole were attained. Tryptamine production led to a much higher titer of 2.26 g L upon expression of AADC from B. atrophaeus. AADC enzymes were shown to be active with halogenated tryptophan in vitro and in vivo and supported production of 0.36 g L 7-Br-tryptamine with a volumetric productivity of 8.3 mg L h in a fed-batch fermentation.
Topics: Corynebacterium glutamicum; Escherichia coli; Fermentation; Indoles; Tryptophan; Tryptophanase
PubMed: 35224830
DOI: 10.1002/cbic.202200007 -
International Journal of Medicinal... 2023Edible mushrooms are important natural foods that have been used since ancient times due to their delicious taste, high nutritional value, and various biological...
Edible mushrooms are important natural foods that have been used since ancient times due to their delicious taste, high nutritional value, and various biological activities. In this study, antibacterial (against 10 different human pathogens) and antioxidant potentials (free radical scavenging activity and total phenol-flavonoid content) of 13 different wild-growing and the most popular edible mushrooms (Lactarius salmonicolor, L. deliciosus, L. volemus, L. piperatus, Boletus edulis, Marasmius oreades, Agaricus campestris, Tricholoma terreum, Hydnum repandum, Coprinus comatus, Ramaria sp., Cantharellus cibarius, and Pleurotus ostreatus) sold in a public bazaar in Bolu-Turkey were evaluated. Strong antibacterial capacities were observed with all tested Lactarius species, as well as M. oreades, A. campestris, T. terreum, H. repandum, and Ramaria sp. Significant antibacterial potentials of T. terreum and C. comatus against Staphylococcus epidermidis, Serratia marcescens, and Proteus vulgaris were observed for the first time. H. repandum strongly inhibited all tested Gram-positive bacteria (Staphylococcus aureus, S. epidermidis, and Streptococcus pyogenes). It was remarkable to reveal strong growth inhibition of M. oreades against S. aureus (29.33 ± 1.11 mm) for the first time. The highest total phenolic content was revealed with L. delicious (193.42 ± 0.77 mg GAE/g dw and 198 ± 0.79 mg TAE/g dw), while L. salmonicolor had the highest total flavonoid content (358.33 ± 15.27 mg CE/g dw). B. edulis demonstrated the strongest antioxidant activity with the lowest IC50 value (4.48 ± 0.04 μg/mL). Moreover, L. deliciosus and M. oreades also had high antioxidant potential with the lowest IC50 values (4.76 ± 0.01 μg/mL and 4.77 ± 0.02 μg/mL, respectively). Total phenolic contents of tested mushrooms were highly correlated with their antioxidant capacities. L. delicious is the most well-known and the most delicious mushroom sold in Bolu's public bazaar. The obtained results for this mushroom were notable in terms of the greatest total phenol-flavonoid content and strong antioxidant capability. The antioxidant capacity and polyphenol content of L. deliciosus, M. oreades, H. repandum, A. campestris, and B. edulis, as well as their antibacterial activity, were quite outstanding, and our findings demonstrated the importance of these mushrooms as nutraceutical products.
Topics: Humans; Antioxidants; Staphylococcus aureus; Agaricales; Anti-Bacterial Agents; Phenols; Pleurotus; Flavonoids
PubMed: 36734918
DOI: 10.1615/IntJMedMushrooms.2022046526 -
Food Science & Nutrition Sep 2022and were identified as specific spoilage organisms (SSOs) isolated from the refrigerated lightly-salted large yellow croaker (). In this work, the inhibitory effects...
and were identified as specific spoilage organisms (SSOs) isolated from the refrigerated lightly-salted large yellow croaker (). In this work, the inhibitory effects of pH, salinity, and tea polyphenols concentration on both strains were investigated. Modified Gompertz models were used to estimate the kinetic parameters (maximum specific growth rate) and (duration of lag phase) of the two strains under different conditions, demonstrating that their growth rates decreased with the decrease of pH as well as the increase of salinity and tea polyphenols concentration, and the growths of both strains stopped while the salinity and tea polyphenols concentration increased to 0.05 and 5%, respectively. Response surface methodology (RSM) based on a three-level three-factor Box-Behnken Design (BBD) was employed to optimize the combination of these three antibacterial factors. The results showed that the optimum inhibitory conditions were: tea polyphenols concentration 0.05%, salinity 3.46%, and pH 6.96 to inhibit the growth of . ; tea polyphenols concentration 0.05%, salinity 3.45%, and pH 6.94 to inhibit . . Validation experiments were performed and demonstrated that under these conditions, the growth of the two SSOs could be 100% inhibited. This research provided references for the inhibition of the SSOs of lightly-salted large yellow croaker and the extension of its shelf life.
PubMed: 36171782
DOI: 10.1002/fsn3.2905 -
Jundishapur Journal of Microbiology Apr 2016Proteus spp. bacilli belong to opportunistic human pathogens, which are primarily responsible for urinary tract and wound infections. An important virulence factor is...
BACKGROUND
Proteus spp. bacilli belong to opportunistic human pathogens, which are primarily responsible for urinary tract and wound infections. An important virulence factor is their ability to form biofilms that greatly reduce the effectiveness of antibiotics in the site of infection.
OBJECTIVES
The aim of this study was to determine the value of the minimum concentration of ciprofloxacin that eradicates a biofilm of Proteus spp. strains.
MATERIALS AND METHODS
A biofilm formation of 20 strains of P. mirabilis and 20 strains of P. vulgaris were evaluated by a spectrophotometric method using 0.1% 2, 3, 5-Triphenyl-tetrazolium chloride solution (TTC, AVANTORTM). On the basis of the results of the absorbance of the formazan, a degree of reduction of biofilm and minimum biofilm eradication (MBE) values of MBE50 and MBE90 were determined.
RESULTS
All tested strains formed a biofilm. A value of 1.0 μg/mL ciprofloxacin is MBE50 for the strains of both tested species. An MBE90 value of ciprofloxacin for isolates of P. vulgaris was 2 μg/mL and for P. mirabilis was 512 μg/mL.
CONCLUSIONS
Minimum biofilm eradication values of ciprofloxacin obtained in the study are close to the values of the minimal inhibition concentration (MIC).
PubMed: 27303616
DOI: 10.5812/jjm.32656 -
BioMed Research International 2022The emergence of multi-drug-resistant organisms has created a lot of clinical problems. Hence, there is a need to find natural alternative treatment to counter the...
BACKGROUND
The emergence of multi-drug-resistant organisms has created a lot of clinical problems. Hence, there is a need to find natural alternative treatment to counter the multi-drug-resistant organisms. Honey has a well-established usage as wound dressing in ancient and traditional medicine.
OBJECTIVE
The objective of this study is to establish a baseline for the antibacterial activity of 32 global raw natural and commercial various honey samples against 8 clinical isolates.
METHODS
Thirty-two honey samples (raw and commercial honey) collected from different global countries with different floral origins were tested for antibacterial activity against 8 clinical isolates collected from patients, at private hospital from Sudan, using disk diffusion technique. The following 6 epsilometer tests (Etest), amoxicillin, ciprofloxacin, cefotaxime, chloramphenicol, gentamicin, and tetracycline, were used against 8 clinical isolates for Minimum Inhibitory Concentration (MIC).
RESULTS
The following 8 clinical isolates were identified by conventional bacteriological methods: (), (. ), (. ), (. ), Typhi ( Typhi), (. ), and methicillin-resistant (MRSA). Both raw natural and commercial honey exhibited antibacterial properties against tested Gram-positive and Gram-negative bacteria. The tested organisms showed low sensitivity to antibiotic Etest.
CONCLUSION
All of the bacterial species studied were uniformly receptive to all raw and commercial tested honey samples; in contrast, the tested organisms showed low sensitivity to antibiotics. Commercial honey has the same antibacterial activity as the raw natural unprocessed honey against tested clinical isolates. Thus, honey is a successful alternative to conventional antibiotics as has been proved against clinical isolates.
Topics: Anti-Bacterial Agents; Escherichia coli; Gram-Negative Bacteria; Gram-Positive Bacteria; Honey; Humans; Klebsiella pneumoniae; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Pseudomonas aeruginosa; Salmonella typhi; Staphylococcus aureus
PubMed: 35097108
DOI: 10.1155/2022/1560050 -
Anti-cancer Agents in Medicinal... 2021A pentacyclic lupenane-type natural triterpenoid, betulin, has attracted attention in the field of medicinal chemistry since it exhibited a variety of biological...
BACKGROUND
A pentacyclic lupenane-type natural triterpenoid, betulin, has attracted attention in the field of medicinal chemistry since it exhibited a variety of biological activities, including anticancer activity.
OBJECTIVE
The aim of this present work was to obtain derivatives of betulin through bacterial biotransformation and investigate its anticancer activity against A549, HepG2 and 5RP7 cancer cell lines.
METHODS
Bacterial biotransformation studies were continued in an MBH broth medium for 7 days at 35oC. Anticancer activities of betulin against A549, HepG2 and 5RP7 cell lines were carried out using XTT assay, and their selectivity was determined using a healthy cell line of NIH/3T3. Cell proliferation ELISA, BRDU (colorimetric) assay was used for measuring proliferation in replicative cells in which DNA synthesis occurs. Flow cytometric analysis was used for measuring apoptotic cell percentages, caspase 3 activation and mitochondrial membrane potential.
RESULTS
Bacterial biotransformation studies with 7 bacteria of Staphylococcus aureus ATCC 6538, Proteus vulgaris NRRL B-123, Bacillus subtilis NRRL B-4378, Streptomyces griseolus NRRL B-1062, Escherichia coli ATCC 8739, Staphylococcus aureus ATCC 43300 and Bacillus velezensis NRRL B-14580 produced no metabolite. In in vitro anticancer activity studies, betulin was found to exert anticancer activity against A549, HepG2 and 5RP7 cell lines with IC50 values of 207.7, 125.0 and 28.3 μg/mL, whereas SI values were found to be 30, 50 and 223, respectively. Early and late apoptotic percentages of betulin were found as 9.6, 12.1 and 85.4% on A549, HepG2 and 5RP7, respectively, while caspase 3 positive cell percentages were 2.3, 28.7 and 13.3% for IC50 concentrations. In addition, betulin caused G1 cell cycle arrest (49.5%) on 5RP7 cell line.
CONCLUSION
The results have been shown that betulin activities against A549 and HepG2 cell lines were nonselective and limited its cytotoxic activity against healthy cells, but it is possible to say that it exerted selective activity against 5RP7 cell (28.33±1.53 μg/mL). Betulin effects on apoptosis were found to be dosedependent, while its effect on caspase 3 activation, mitochondrial membrane potential, and cell cycle arrest on G0/G1 phase was not dependent on doses. Therefore, betulin could be a good candidate for the treatment of H-ras active cancer types.
Topics: Animals; Antineoplastic Agents; Apoptosis; Bacillus; Bacillus subtilis; Biotransformation; Cell Line; Cell Proliferation; Cell Survival; DNA, Neoplasm; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Escherichia coli; Humans; Mice; Molecular Conformation; Proteus vulgaris; Staphylococcus aureus; Streptomyces; Structure-Activity Relationship; Triterpenes
PubMed: 33121415
DOI: 10.2174/1871520620666201029102400 -
Food Research International (Ottawa,... Nov 2017The effect of nitrate and the combination of nitrate/nitrite on Listeria innocua (as surrogate of Listeria monocytogenes). And two selected spoilage microorganisms...
The effect of nitrate and the combination of nitrate/nitrite on Listeria innocua (as surrogate of Listeria monocytogenes). And two selected spoilage microorganisms (Proteus vulgaris and Serratia liquefaciens) was studied in dry-cured ham. Hams were manufactured with different concentrations of curing agents: KNO (600 and 150mg/kg) alone or in combination with NaNO (600 and 150mg/kg). The addition of 500mg/kg of sodium ascorbate was also evaluated in a batch with 600mg/kg of nitrate and nitrite. The target microorganisms were inoculated by injection in semimembranosus, biceps femoris and in the shank, prior to curing. P. vulgaris and S. liquefaciens were controlled by temperature and a, respectively, and no effect of nitrate/nitrite was observed. The presence of nitrite in the curing mix reduced L. innocua in semimembranosus, which population was 1.5logcfu/g lower at the end of resting (p<0.05), while at the end of the process it was more frequently detected in the no- and low-nitrite added hams. None of the treatments was able to control Listeria in deeper areas of ham. The addition of sodium ascorbate to the curing mix containing the highest amount of nitrate and nitrite did not show any effect on the microorganisms studied.
Topics: Animals; Ascorbic Acid; Colony Count, Microbial; Desiccation; Drug Combinations; Food Contamination; Food Microbiology; Food Preservation; Food Preservatives; Hamstring Muscles; Hydrogen-Ion Concentration; Listeria; Meat Products; Microbial Sensitivity Tests; Nitrates; Nitrites; Potassium Compounds; Proteus vulgaris; Red Meat; Serratia liquefaciens; Sodium Nitrite; Swine
PubMed: 28941700
DOI: 10.1016/j.foodres.2017.08.039