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Bioinformation 2022There is a shred of evidence to suggest that Emblica officinalis Gaertn, the botanical name for amla seeds, has greater medicinal potential than amla fruit. We conducted...
There is a shred of evidence to suggest that Emblica officinalis Gaertn, the botanical name for amla seeds, has greater medicinal potential than amla fruit. We conducted this work to assess the anti-inflammatory, antibacterial, and antioxidant capacities of E. officinalis seed extracts. The bioactive components from the seeds were fractionated using chloroform, hexane, methanol, and diethyl ether, according to the polarity of the solvents. The total amount of phenolic and flavonoid was estimated. Both the reducing power and antioxidant capacities of the extracts were evaluated using the DPPH (1,1-diphenyl-2-picryl-hydrazyl) technique. 15-lipoxygenase (LOX) was inhibited by seed extracts at doses ranging from 5 to 25 micrograms. In silico docking was employed to assess the results. Some human pathogenic microorganisms were tested for their antibacterial activity using the agar disc diffusion method. Escherichia coli, Proteus vulgaris, and Klebsiella pneumonia were inhibited by a methanolic extract with an IC50 value of 58g, making it the most common organic solvent extract. Methanolic extracts also showed good antioxidant and antibacterial activity. Our investigation led us to discover that amla seeds have anti-inflammatory, antioxidant, and antibacterial effects.
PubMed: 37323557
DOI: 10.6026/97320630018683 -
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 -
Antibiotics (Basel, Switzerland) Jun 2023The overuse and misuse of antibiotics can pose the risk of spreading mutant strains that show antimicrobial resistance (AMR), with negative impacts on the management of...
The overuse and misuse of antibiotics can pose the risk of spreading mutant strains that show antimicrobial resistance (AMR), with negative impacts on the management of bacterial infections and economic implications for healthcare systems. The research and development of natural antibacterial agents could be a priority in the next years to improve a number of effective antibacterial molecules and to reduce the AMR phenomenon and its development. The present study identified the most effective concentration and contact time of L. essential oil (TEO) to obtain bactericidal effects in vitro against different Gram-positive and Gram-negative bacterial strains. Six clinically isolated (wild types) bacterial strains, (, and ) and two ATCCs ( and ) were tested after 1 min, 3 min and 5 min of contact with TEO. The preliminary results on after 24 h of incubation revealed a TEO concentration of 9.28 mg/mL (/) that completely inhibited bacteria growth, keeping cell viability. The total suppression of bacterial growth at all tested contact times was observed for all tested bacterial strains, and the results were confirmed after 48 h of incubation. Bacterial growth suppression was confirmed even with the presence of organic components. These preliminary results showed the in vitro antimicrobial efficacy of TEO against different Gram-positive and Gram-negative bacterial strains. Future studies are necessary to confirm the reproducibility of these results even on other strains and to define the exact molecular mechanisms of EOs in order to consider TEO as a valid alternative to classic antibiotic therapies and subsequently to reduce the occurrence of AMR.
PubMed: 37508225
DOI: 10.3390/antibiotics12071129 -
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 -
Nanomaterials (Basel, Switzerland) Feb 2024The purpose of this study was to investigate the antimicrobial activity of citrate-stabilized sols of cerium oxide nanoparticles at different concentrations via...
The purpose of this study was to investigate the antimicrobial activity of citrate-stabilized sols of cerium oxide nanoparticles at different concentrations via different microbiological methods and to compare the effect with the peroxidase activity of nanoceria for the subsequent development of a regeneration-stimulating medical and/or veterinary wound-healing product providing new types of antimicrobial action. The object of this study was cerium oxide nanoparticles synthesized from aqueous solutions of cerium (III) nitrate hexahydrate and citric acid (the size of the nanoparticles was 3-5 nm, and their aggregates were 60-130 nm). Nanoceria oxide sols with a wide range of concentrations (10-10 M) as well as powder (the dry substance) were used. Both bacterial and fungal strains (, , , , , , , ) were used for the microbiological studies. The antimicrobial activity of nanoceria was investigated across a wide range of concentrations using three methods sequentially; the antimicrobial activity was studied by examining diffusion into agar, the serial dilution method was used to detect the minimum inhibitory and bactericidal concentrations, and, finally, gas chromatography with mass-selective detection was performed to study the inhibition of growth. To study the redox activity of different concentrations of nanocerium, we studied the intensity of chemiluminescence in the oxidation reaction of luminol in the presence of hydrogen peroxide. As a result of this study's use of the agar diffusion and serial dilution methods followed by sowing, no significant evidence of antimicrobial activity was found. At the same time, in the current study of antimicrobial activity against strains using gas chromatography with mass spectrometry, the ability of nanoceria to significantly inhibit the growth and reproduction of microorganisms after 24 h and, in particular, after 48 h of incubation at a wide range of concentrations, 10-10 M (48-95% reduction in the number of microbes with a significant dose-dependent effect) was determined as the optimum concentration. A reliable redox activity of nanoceria coated with citrate was established, increasing in proportion to the concentration, confirming the oxidative mechanism of the action of nanoceria. Thus, nanoceria have a dose-dependent bacteriostatic effect, which is most pronounced at concentrations of 10-10 M. Unlike the effects of classical antiseptics, the effect was manifested from 2 days and increased during the observation. To study the antimicrobial activity of nanomaterials, it is advisable not to use classical qualitative and semi-quantitative methods; rather, the employment of more accurate quantitative methods is advised, in particular, gas chromatography-mass spectrometry, during several days of incubation.
PubMed: 38392727
DOI: 10.3390/nano14040354 -
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 -
Frontiers in Plant Science 2023Medicinal plants have been considered as potential source of therapeutics or as starting materials in drugs formulation.
INTRODUCTION
Medicinal plants have been considered as potential source of therapeutics or as starting materials in drugs formulation.
METHODS
The current study aims to shed light on the therapeutic potential of the and Fruits by analyzing the phytochemical composition of their seeds and fruits using gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC) techniques to determine the presence of bioactive components such as flavonoids, phenols, vitamins, steroids, and essential oils.
RESULTS AND DISCUSSION
The protein content is usually higher than the total lipids in both species except the fruit of which contain more lipids than proteins. The total protein contents for were 235.03 ± 21.49 and 227.49 ± 25.82 mg/g dry weight while for were 201.9 ± 37.79 and 294.99 ± 37.93 mg/g dry weight for seeds and fruit, respectively. The Carvacrol levels in is 20 times higher than that in . Lower levels of α-Thujene, Phyllanderenes, Ascaridole, and Pinocarvone were also observed in both species. According to DPPH (2,2-diphenylpicrylhydrazyl) assay, seed the extract of exhibited the highest antioxidant activity (78.26±9.27 %) followed by the seed extract of (68.21±2.56 %). Similarly, FRAP (Ferric Reducing Antioxidant Power) assay showed that the highest antioxidant activity was exhibited by the seed extract of the two species; 20.14±1.11 and 21.18±1.04 µmol trolox g-1 DW for and , respectively. In terms of anti-lipid peroxidation, relatively higher values were obtained for the fruit extract of (6.08±0.35) and the seed extract of (6.11±0.55). Ethanolic seed extracts of had the highest efficiency against four Gram-negative bacterial species which causes serious human diseases, namely , , , and . In addition, was also inhibited by the fruit extract of both and . For the seed extract of , large inhibition zones were formed against and the fungus . Finally, we have explored the mode of action of these plants by performing detailed molecular modeling studies and showed that the antimicrobial activities of these plants could be attributed to the high binding affinity of their bioactive compounds to bind to the active sites of the sterol 14-alpha demethylase and the transcriptional regulator MvfR.
CONCLUSION
These findings demonstrate the two species extracts possess high biological activities and therapeutical values, which increases their potential value in a number of therapeutic applications.
PubMed: 37152127
DOI: 10.3389/fpls.2023.1136961 -
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 -
Scientific Reports Apr 2022Secondary plant metabolites remain one of the key sources of therapeutic agents despite the development of new approaches for the discovery of medicinal drugs. In the...
Secondary plant metabolites remain one of the key sources of therapeutic agents despite the development of new approaches for the discovery of medicinal drugs. In the current study, chemical analysis, and biological activities of Kei apple (Dovyalis caffra) methanolic extract were evaluated. Chemical analysis was performed using HPLC and GC-MS. Antiviral and anticancer effect were assessed using the crystal violet technique and activity against human liver cells (HepG2), respectively. Antibacterial activity was tested with the disc diffusion method. The obtained results showed that chlorogenic acid (2107.96 ± 0.07 µg/g), catechin (168 ± 0.58 µg/g), and gallic acid (15.66 ± 0.02 µg/g) were the main bioactive compounds identified by HPLC techniques. While, compounds containing furan moieties, as well as levoglucosenone, isochiapin B, dotriacontane, 7-nonynoic acid and tert-hexadecanethiol, with different biological activities were identified by GC-MS. Additionally, inhibition of 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) scavenging was 79.25% at 2000 µg/mL, indicating its antioxidant activity with IC of 728.20 ± 1.04 µg/mL. The tested extract exhibited potential anticancer activity (58.90% toxicity) against HepG2 cells at 1000 µg/mL. Potential bacterial inhibition was observed mainly against Escherichia coli and Proteus vulgaris, followed by Staphylococcus aureus and Bacillus subtilis with a diameter of growth inhibition ranging from 13 to 24 mm. While weak activities were recorded for fungi Candida albicans (10 mm). The extract showed mild antiviral activity against human coronavirus 229E with a selective index (SI) of 10.4, but not against human H3N2 (SI of 0.67). The molecular docking study's energy ratings were in good promise with the experiment documents of antibacterial and antiviral activities. The findings suggest that D. caffra juice extract is a potential candidate for further experiments to assess its use as potential alternative therapeutic agent.
Topics: Anti-Bacterial Agents; Antioxidants; Antiviral Agents; Fruit; Humans; Influenza A Virus, H3N2 Subtype; Molecular Docking Simulation; Plant Extracts; Salicaceae
PubMed: 35396383
DOI: 10.1038/s41598-022-09993-1 -
BMJ Open Sep 2021To investigate the bacterial aetiologies and associated risk factors of gastroenteritis among typhoid suspected cases.
OBJECTIVES
To investigate the bacterial aetiologies and associated risk factors of gastroenteritis among typhoid suspected cases.
DESIGN
Cross-sectional study.
SETTING
This study was conducted at Dschang District Hospital of the Menoua Division, West Region of Cameroon, between April-November 2019 and June 2020.
PARTICIPANTS
Participants aged ≥2 years (mean 34±18.77 years) and of both sex suspected of having typhoid fever were included, while non-suspected typhoid cases were excluded. Self-reported sociodemographic and health information at recruitment was obtained from 556 participants.
METHODS
Collected stool samples were examined macroscopically and microscopically and subjected to culture. After culture, Gram staining was performed, followed by biochemical testing and characterisation using the Analytical Profile Index (API-20E) test kit.
INTERVENTIONS'
No intervention was done during the period of study.
OUTCOME MEASURES
We identified bacterial causing gastroenteritis, and associated risk factors calculated using binary regression, adjusting for sociodemographic and health variables.
RESULTS
Of 556 patients, 74.28% tested positive for gastroenteritis. Among pathogens responsible for gastroenteritis, was found to be the main cause (21.1%), followed by (10.4%), (8.2%), (8.2%), (7.3%), whereas spp and were less represented among pathogens causing the disease among patients. A significant difference (p=0.002) was observed between abdominal pain and all the micro-organisms isolated from the patients. Patients having primary level of education were significantly associated (p=0.017; 3.163 (95% CI 1.228 to 8.147)) with the prevalence of gastroenteritis. Consumption of beverages (Wald statistic: 4.823; OR: 2.471; 95% CI (1.102 to 5.539); p=0.028), use of modern toilet (Wald statistic: 4.471; OR: 1.723; 95% CI (1.041 to 2.852); p=0.034) were strongly associated with gastroenteritis and rearing of bird (Wald statistic: 4.880; OR: 0.560; 95% CI (0.335 to 0.937); p=0.027), was found to be protective.
CONCLUSION
Acute bacterial gastroenteritis is a significant cause of morbidity in Dschang, with the prevalence of 74.28%. Many pathogens accounted for gastroenteritis, and (21.1%) could be a major cause, followed by (10.4%), (8.2%), (8.2%), (7.3%), whereas spp and were less represented. Gastroenteritis was highly associated with primary level of education, consumption of beverages, use of modern toilet while rearing of birds was unexpectedly found to be protective against Gastroenteritis. Further characterisation is planned.
Topics: Cameroon; Cross-Sectional Studies; Escherichia coli; Gastroenteritis; Hospitals, District; Humans; Outpatients; Risk Factors
PubMed: 34518249
DOI: 10.1136/bmjopen-2020-045965