Inhibition Diameter Research Articles

Synthesis of green-engineered silver nanoparticles using Cymbopogon citratus (lemongrass) and its antibacterial activity against clinical Pseudomonas aeruginosa

Background and Aim: The use of bioengineered nanocomposites as antimicrobials has increased in recent years, but very few investigations have been conducted to test their effectiveness against Pseudomonas aeruginosa, a pathogen presenting public health risks that can impact both humans and animals. The aim of this study was to assess the antimicrobial potential of phytofabricated silver nanoparticles synthesized using lemongrass extract against clinical isolates of P. aeruginosa. Materials and Methods: The extraction of active compounds from the leaves of Cymbopogon citratus was performed using ethanol (80%) as a solvent, high-performance liquid chromatography-mass spectrometry was used to analyze the chemical composition of the extract, the synthesis of silver nanoparticles (AgNPs) was done using silver nitrate (AgNO3) as a precursor, and the antimicrobial and antibiofilm activity of the extract and the AgNPs phytofabricated was assessed against 10 clinical strains of P. aeruginosa. Results: Lemongrass extract was found to consist of the following main compounds: Caffeic acid (445.21 ± 32.77 μg/g), p-coumaric acid (393.32 ± 39.56 μg/g), chlorogenic acid (377.65 ± 4.26 μg/g), quinic acid (161.52 ± 17.62 μg/g), and quercetin-3-glucoside (151.35 ± 11.34 μg/g). AgNPs were successfully phytofabricated using 2.5 mM AgNO3. The ultraviolet (UV)-visible absorption spectra of the AgNPs showed a localized surface plasmon resonance at 464 nm with an absorbance of 0.32 A. The 50x hydrodynamic diameter was 50.29 nm with a surface area value of 120.10 m2/ cm3, and the volume mean diameter and Sauter mean diameter were 50.63 nm and 49.96 nm, respectively. Despite the compound found in lemongrass extract, no antimicrobial activity was observed with the extract, while AgNPs exhibited noteworthy dose-dependent antimicrobial activity with inhibition diameters up to 24 mm and minimum inhibitory concentration (MIC) and minimum bactericidal concentration ranging from 2 to 16 and 4–64 µg/mL, respectively. AgNPs also demonstrated significant antibiofilm activity by inhibiting biofilms up to 99% between MIC/2 and 2MIC. Conclusion: The present study suggests that lemongrass is a good candidate for the synthesis of AgNPs with good physicochemical characteristics and having a strong anti-pseudomonas activity. Further research is needed to assess the stability and safety of these AgNPs. Keywords: antibiofilm capacity, antimicrobial activity, green synthesis, lemongrass, Pseudomonas aeruginosa, silver nanoparticles.

Antimicrobial screening of pecan shell extract and efficacy of pecan shell extract-pullulan coating against Listeria monocytogenes, Salmonella enterica, and Staphylococcus aureus on blueberries

Pecan shell is considered an agricultural waste; however, it contains various bioactive compounds with potential inhibitory effect against microorganisms. This study evaluated the antimicrobial efficacy of pecan shell extract (PSE) in vitro using disc-diffusion method and in vivo on blueberries as an antimicrobial coating using pullulan. For in vitro study, 5 and 10 % of aqueous (A-PSE) or ethanol pecan shell extract (E-PSE) incorporated into pullulan film were tested against different bacterial and fungal strains. Pullulan film disc was used as control. The diameter of growth inhibition (mm) around discs was measured. For in vivo study, PSE-P (5 % w/v aqueous pecan shell extract+5 % w/v pullulan), P (5 % w/v pullulan) or control (water) were spray coated on blueberries inoculated (∼5 log CFU/g) with Listeria monocytogenes, Salmonella enterica or Staphylococcus aureus; and stored at 4 °C, 50 ± 10 % RH for 15 days. The effect of antimicrobial coating against pathogens and its impact on quality during storage were determined. A-PSE and E-PSE films were more effective against Gram-positive bacteria and showed no antifungal effect at tested concentrations when evaluated in vitro. Immediately after coating on blueberries, PSE-P significantly reduced Listeria monocytogenes by 2 log CFU/g and lowered survival until day 5 than control or P. Native aerobic microbial population was reduced (P < 0.05) by 0.7 log CFU/g immediately after coating. PSE-P coating or storage time had no significant effect (P > 0.05) on the survival of S. enterica, S. aureus and native fungal population. PSE-P maintained the firmness of blueberry with no significant effect on its color, TSS, and pH during 15 days storage. PSE-P significantly reduced (P < 0.05) the spoilage rate by 21 % than control (28.5 %) and P (37 %); and minimized (P < 0.05) weight loss during storage. Pecan shell extracts show promise as a potential antimicrobial compound whose application on various food products or packaging material could be further explored.

Investigation of biological activities of essential oil obtained from peel of wild orange in Quang Ngai by steam distillation

Wild orange abundantly and naturally occuring in mountainous regions of Western Quang Ngai (Vietnam) has been commonly collected and consumed as a unique fruit with a low economic value. In this study, to propose the healthy benefits from this wild fruit, steam distillation was applied to extract essential oil from its peel with an extraction efficiency of approx. 3.85 wt.%. Gas chromatography-mass spectrometry (GC-MS) was employed to evaluate the chemical makeup of the essential oil obtained, in which, D-limonene (78.4%) and β-myrcene (2.4%) were found to be the most significant among 44 detected compounds. The in vitro antifungal activity of the essential oil against Candida Albicans (C.albicans) and Malassezia Furfur (M.furfur) was discovered using the zone-of-inhibition (ZOI) method. The experimental result showed that the inhibition to C.albicans was significant at a high concentration of the essential oil while the inhibition to M.furfur was better even at a low concentration (2.5 mg/mL) with an inhibitory ring diameter of 27 ± 0.3 mm, proving the great potential of this essential oil towards pharmaceutical and biological applications.

In Vitro Evaluation of Phosphate Solubilizing Bacteria as Antagonists for Bacterial Leaf Blight Disease (Xanthomonas oryzae pv. oryzae)

Rice is an important food crop in Indonesia, where more than 50% of the Indonesian population consumes rice as a staple food. Rice has decreased productivity by 50-80% due to bacterial leaf blight caused by Xanthomonas oryzae pv. oryzae (Xoo). The rapid spread and damaging effects of pesticide use on the environment are the main obstacles in the treatment of these bacteria. Alternative control is to use biological agents in the form of phosphate solubilizing bacteria (PSB). Phosphate solubilizing bacteria are part of the growth-promoting bacteria that have other abilities, namely biocontrol. The purpose of this study was to develop the ability of acid soil phosphate solubilizing bacteria to inhibit growth in vitro. The test was carried out using the dual culture technique with the zone of inhibition method. The results showed that ten isolates of PSB had inhibition against Xoo with various diameters of inhibition. The four highest inhibitory isolates were EF.NAP 3 (5.267 ± 0.189 mm), Pseudomonas GSP 6 (4533 ± 0.772 mm), EF.NAP 4 (3,424 ± 0.161 mm) and EF. NAP 9 (3.167±0.136 mm). The ability of PSB to inhibit Xoo can be used as an alternative in controlling bacterial leaf blight in rice plants. This indicates that the PSB isolate acts as a biostimulant in the dissolution of phosphate in the soil and as a bioprotectant.

Effects of Soaking Time and Peppermint Oil Concentration on Chemical, Sensory, and Antibacterial Characteristics of Robusta Coffee (Coffea canephora)

The increase in public coffee consumption is influenced by lifestyle, technological support and the emergence of various choices of coffee. Herbal coffee is generally made by adding herbal powder, infusion, and drying. Soaking techniques with peppermint oil to make herbal coffee have never been studied. The purpose of this study was to determine the effect of robusta coffee treated with soaking time and peppermint oil concentration on chemical characteristics, sensory and antimicrobial activity. Randomized Complete Group Design method with two factors was performed in this study. The first factor is soaking time (L) which consists of 0 (L0), 5 (L1), and 10 (L2) min. The second factor was peppermint oil concentration consisting of 0% (K0); 0.5% (K1); and 0.75% (K2). The results showed that the soaking time and concentration of peppermint oil can increase the water content and pH. The peppermint coffee showed antimicrobial activity against Salmonella typhi and Eschericia coli bacteria with an inhibition diameter of 8.72-13.16 mm and 9.88-12.24 mm, respectively. The peppermint coffee of L1K1 treatment (5 min soaking time; 0.5% peppermint concentration), is preferred by panelists with sensory test scores on taste (6.15), aroma (7.09), aftertaste (5.32), and overall (6.16). Keywords: Coffee bean, Concentration, Peppermint oil, Robusta coffee, Soaking time.

Pengaruh penambahan sari buah naga merah pada yoghurt susu kedelai serta uji aktivitas antibakteri

Food is one of the most important needs for humans because it relates to daily nutritional needs. The solution to this problem is to consume food with good nutritional content supported by appropriate food processing innovations. Milk can be drunk directly or processed into various forms of food and drinks with milk-based ingredients, such as yogurt. This study aims to make yogurt products from soy milk using red dragon fruit juice as a substitute for sugar and to test their antibacterial activity in inhibiting Salmonella typhi and Shigella dysenteriae bacteria. This study used a completely randomized design (CRD) with 3 treatments, namely the addition of red dragon fruit juice with concentrations of 5%, 10%, and 15%, 3 replications, and the diffusion method for testing antibacterial activity. The results showed that the best yoghurt formula was obtained from F3 (yoghurt with the addition of 15% concentration of red dragon fruit juice). The panelist hedonic test gives values ranging from slightly like to like for color, aroma, taste, and texture; for organoleptic F3, these are: color (dark pink), taste (sour), texture (liquid-thick), and aroma (typical); pH 3.49; TAT 1.39%; Lactic Acid Bacteria (LAB) 2.09 x 1010 CFU/mL; and also had an average diameter of inhibition of 18.96 mm against Salmonella thypi (P&lt;0.05) and 20.10 mm against Shigella dysenteriae (p&lt;0.05). Soy milk yogurt with the addition of varying concentrations of red dragon fruit juice has antibacterial activity.

Isolation and Identification of Shigella SonneiProducing Shiga Toxin from Children with Bloody Diarrhea and Evaluation of the Inhibition Effectiveness of Zinc oxide Nanoparticles

Shigella infection strains producing shiga toxin results in bloody diarrheais a dangerous symptom in children under five years of age that can even lead to death. Therefore, this study was conducted to isolate Shigella strains producing shiga toxin from 150 samples which were taken from bloody stool of children under the five years of age. They were suffering from the diarrhea during the period from March 2021 to March 2022 in Tikrit city, Iraq. The results showed the possibility to isolate six isolates of Shigella sonnei at ratio 4% of the total samples. The isolates producing shiga toxin were identified by using stx1 gene. The results showed two isolates of Shigella possessing stx1 gene, at ratio 33.33 of total S. sonnei strains. The two isolates producing shiga toxin have been submitted to NCBI, then accepted as Iraqi strains in NCBI under the registration numbers OK127759.1 and OK127760.1. The Iraqi strains registered in NCBI showed agreement with a global strain of 99-100% that were recorded by registration numbers in Malaysia (CP060117.1), China (CP000038.1), United Kingdom (CP066810.1), Hungary (CP019689.1), Somalia (CP023645.1), Spain (CP022672.1), Italy (CP035008.1), India (CP041322.1), Australia (CP045932.1), Nigeria (CP046286.1), Switzerland (CP049183.1), USA (CP053751.1) and South Korea (CP055292.1). As for the sensitivity test, the results showed that the strain OK127759.1 was resistant to antibiotics azithromycin, ceftazidime, cefotaxime, ceftriaxone, augmentin and tetracycline. And it was sensitive to gentamicin and intermediately sensitive to ampicillin, chloramphenicol and nalidixic acid. As for the strain OK127760.1, the results showed his strain was intermediately sensitive to gentamicin and resistant to the other antibiotics which were used in the test. ZnO-NPs with a concentration of 200 μg/ml showed the highest inhibitory effectiveness against S. sonnei strains OK127759.1 and OK127760.1 with inhibition diameter of 22 mm and 21 mm respectively.

Chemical composition and antifungal activity of Teucrium Leucocladum Boiss. essential oils growing in Egypt using two different techniques

BackgroundTeucrium Leucocladum Boiss. (TL) (family Lamiaceae), indigenous to Sinai, Egypt, and Mediterranean region, is considered a rich source of essential oils (EOs). This study aimed to extract the aerial parts essential oils utilizing hydro-distillation (HD) and microwave-assisted extraction (MAE), and analyze the volatile constituents by Gas Chromatography–Mass Spectrometry (GC/MS). The antifungal and cytotoxic potentials against Candida albicans (C. albicans) and non-small cell lung adenocarcinoma A549, triple-negative breast cancer MDA-MB-231 cell lines, respectively, were likewise estimated. Subsequently, the three main compounds were docked into the crystal structure of Candida albicansN-myristoyltransferase (NMT) with myristoyl-COA and peptidic inhibitor (PDB 1IYK), and predictions of human absorption, distribution, metabolism, and excretion (ADME) were performed to assess the drug-likeness of the compounds.ResultsThe chemical profile consisted of monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpene hydrocarbons, and oxygenated sesquiterpenes. The MAE oil sample (TLM) yield was found to be double that of the HD oil sample (TLH). TLM afforded an inhibitory diameter (13 mm) comparable to the ketoconazole (20 mm), TLM 100 mg/mL showed the strongest antifungal potential against C. albicans. The cytotoxic assay revealed moderate activity against A549 and MDA-MB-231. In silico studies using molecular docking were processed on the major components in which nerolidol had the best-fitting energy to inhibit C. albicans (− 7.21 kcal/mol), while ADME results established a promising first step for the potential drug bioavailability.ConclusionIn this research, essential oil acquired from the aerial parts proved to contain monoterpenes and sesquiterpenes, which are classes of compounds known for their versatile usage in medicine. In vivo studies on Teucrium Leucocladum Boiss. active metabolites against clinical strains of fungi need to be further studied, as do the effects of combining the active compounds with antifungal agents to combat antimicrobial resistance.

Metabolomics Approach to Explore Bioactive Natural Products Derived From Plant-Root-Associated Streptomyces.

Streptomyces, a prominent genus within the Actinomycetota phylum, is responsible for over 60% of clinically relevant antibiotics. Streptomyces strains inhabiting plant roots possess the potential to synthesize bioactive natural products, conferring defense and resilience to plants against pathogenic microorganisms. However, this potential remains largely unexplored. This study aims to screen for bioactive metabolites produced by Streptomyces strains in the plant rhizosphere.Six Streptomyces isolates were cultivated using three modified media to induce the production of diverse metabolites, employing the One Strain Many Compounds (OSMAC) approach. The metabolites present in extracts from fermentation broths were examined through a non-targeted Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) approach coupled with Global Natural Products Social Molecular Networking (GNPS MN). The antimicrobial activity of the extracts was assessed using the disc diffusion method.The strains demonstrated a wide-ranging antimicrobial efficacy against all examined organisms. The GNPS molecular network analyses reveal that metabolite profiles in extracts can exhibit variations based on the medium and solvent system employed. Notably, the ethyl acetate and dichloromethane extracts from Streptomyces sp. CAH29, cultivated in Glucose-Yeast Extract Medium (GYM), exhibited inhibition diameters of up to 30mm against both Staphylococcus aureus and Candida albicans. Within the metabolomes of these strains, the antibiotics spiramycin and actinomycin were detected. Additionally, lyngbatoxin, a tumor promoter, and potential new analogs were identified. Significantly, a considerable portion of the produced metabolites did not align with any known compounds, indicating the existence of unidentified metabolites generated by these strains. This suggests the possibility of introducing novel chemical entities.Our study illustrated that Streptomyces strains associated with plant roots could be considered a valuable source of bioactive secondary metabolites. Furthermore, the metabolomics approach utilized in this study serves as a rapid and valuable tool for the screening of microorganisms capable of producing bioactive metabolites.

Comparative study of volatile oil constituents, anti-microbial properties, and antibiofilm activities in Eucalyptus camaldulensis and Eucalyptus globulus: insights from central Saudi Arabia

Eucalyptus is a fragrant plant with a highly volatile oil content grown worldwide. This study investigated the phytochemical and biological features of two Eucalyptus species, E. camaldulensis and E. globulus, cultivated in Central Saudi Arabia. Phytochemical analysis revealed 17 compounds in E. camaldulensis and 13 in E. globulus, with α-pinene and 1,8-cineole being both plants’ most abundant volatile components. The antimicrobial activity revealed that Salmonella typhimurium ATCC 13311 and Candida albicans ATCC 10231 are the most susceptible to E. camaldulensis, with the zone of inhibition diameters (ZIDs) of 17.0 ± 0.2 mm and 22.0 ± 0.3 mm, respectively. In contrast, for E. globulus, methicillin-resistant Staphylococcus aureus and Candida albicans ATCC 10231 were the most susceptible, with ZIDs of 13.0 ± 0.2 mm and 20.0 ± 0.2 mm, respectively. E. camaldulensis had minimum inhibitory concentration (MIC) range from 1.56 to 12.5 μL/mL, minimum biocidal concentration (MBC) range from 3.125 to 25.0 μL/mL, minimum biofilm inhibitory concentration (MBIC) range from 3.125 to 25.0 μL/mL, and minimum biofilm eradication concentration (MBEC) from 6.25 to 50.0 μL/mL, while E. globulus had MIC range from 3.125 to 12.5 μL/mL, MBC range from 6.25 to 25.0 μL/mL, MBIC range from 6.25 to 25.0 μL/mL, and MBEC range from 12.5 to 50.0 μL/mL, for the tested organisms. E. camaldulensis demonstrated better antimicrobial activity than E. globulus against the tested organisms, making it a promising antimicrobial drug candidate. Further research is required to determine its effectiveness in treating different human infections.

Green synthesis and characterization of silver nanoparticles from Ducrosia flabellifolia Boiss. aqueous extract: Anti-quorum sensing screening and antimicrobial activities against ESKAPE pathogens.

Biosynthesis of silver nanoparticles using natural compounds derived from plant kingdom is currently used as safe and low-cost technique for nanoparticles synthesis with important abilities to inhibit multidrug resistant microorganisms (MDR). ESKAPE pathogens, especially MDR ones, are widely spread in hospital and intensive care units. In the present study, AgNPs using Ducrosia flabellifolia aqueous extract were synthesized using a reduction method. The green synthesized D. flabellifolia-AgNPs were characterized by UV-Vis spectrophotometer, Scanning electron microscopy (SEM), and X-ray diffraction assays. The tested D. flabellifolia aqueous extract was tested for its chemical composition using Liquid Chromatography-Electrospray Ionization-Mass Spectrometry (LC-ESI-MS). Anti-quorum sensing and anti-ESKAPE potential of D. flabellifolia-AgNPs was also performed. Results from LC-ESI-MS technique revealed the identification of chlorogenic acid, protocatechuic acid, ferulic acid, caffeic acid, 2,5-dihydroxybenzoic acid, and gallic acid as main phytoconstituents. Indeed, the characterization of newly synthetized D. flabellifolia-AgNPs revealed spherical shape with mean particle size about 16.961±2.914 nm. Bio-reduction of silver was confirmed by the maximum surface plasmon resonance of D. flabellifolia-AgNPs at 430 nm. Newly synthetized D. flabellifolia-AgNPs were found to possess important anti-ESKAPE activity with low minimal inhibitory concentrations (MICs) ranging from 0.078 to 0.312 mg/mL, and low minimal bactericidal concentrations (MBCs) varying from 0.312 to 0.625 mg/mL. Moreover, D. flabellifolia-AgNPs were active against Candida utilis ATCC 9255, C. tropicalis ATCC 1362, and C. albicans ATCC 20402 with high mean diameter of growth inhibition at 5 mg/mL, low MICs, and minimal fungicidal concentrations values (MFCs). The newly synthetized D. flabellifolia-AgNPs were able to inhibit violacein production in Chromobacterium violaceum, pyocyanin in Pseudomonas aeruginosa starter strains. Hence, the newly synthesized silver nanoparticles using D. flabellifolia aqueous extract can be used as an effective alternative to combat ESKAPE microorganisms. These silver nanoparticles can attenuate virulence of Gram-negative bacteria by interfering with the quorum sensing system and inhibiting cell-to-cell communication.

Resistance of a mixed bacterial culture isolated from bee dysbiosis to disinfectant in laboratory conditions

Disinfection is one of the components of preventive actions to prevent disease in animals by infectious agents. Through the elimination of agents of infectious diseases in the environment, it is able to interrupt the mechanisms of the epizootic process. For the development of beekeeping and obtaining quality and products, it is necessary to carry out activities in apiaries, which include disinfection. The introduction of new disinfectants in the field is possible after preliminary laboratory tests. The aim of our research objective to investigate the resistance of a mixed bacterial culture isolated from bees with the symptoms of dysbiosis to disinfectant under laboratory conditions. Bacteriological investigations carried out in Petri dishes using meat-peptone agar and Mueller-Hinton agar. The disinfectant diluted with distilled water at concentrations of 0.25 %, 0.5 %, 1,25 % and 2,5 %. On the Mueller Hinton agar, the bacterial elimination zones recorded at 1.25 % (11,6 ± 0,45 mm) and 2.5 % (12,4 ± 0,27 mm) concentration of disinfectant at 1 day of investigation, and 7,4 ± 0,27 mm (1,25 %), 11,2 ± 0,42 mm (2.5 %) at 72 hours of the experiment, respectively. In addition, the bacterial growth inhibition effect increased with experimental time and ranged from 24.0 ± 0.35 mm (0.5 %) to 28.2 ± 0.22 mm (2.5 %) on day 3 of the study. Bacteriostatic and bactericidal effects appeared to be less pronounced on meat-peptone agar. The highest diameters of inhibition of the processes of reproduction and development of microorganisms from mixed microbial association on this medium were recorded at 1.25 % and 2.5 % concentrations of the disinfectant at the 3rd day of the investigation with diameters of the zones of inhibition of growth 15.6 ± 0.45 mm and 26.4 ± 0.27 mm, respectively. The specificity of diffusion of the investigated active substance from the discs into the agar medium thickness was also noted. This effect has a varying effect on infectious agents in in vitro experiments. Thus bacteriological laboratory experiments should be performed on several culture media in purpose of obtaining accurate results. The analysis of the obtained results indicates the demonstration of antimicrobial effect of the investigated disinfectant against mixed bacterial culture in the form of bactericidal and bacteriostatic actions. Therefore, a promising direction of research for veterinary doctors and apiary business owners is the search for effective and efficient disinfectants. Laboratory investigation of the activity of a remedy are the first step before it is approbation.

FORMULATION AND ANTIBACTERIAL ACTIVITY OF HERBAL TOOTHPASTE BASED ON ACEH TRADITIONAL MEDICINE

This research is based on Acehnese traditional medicine containing betel leaf, areca nut, kencur rhizome, gambier sap, and clove buds. Traditionally, all parts of the plant are wrapped in betel leaf folds and chewed to maintain oral health. This study aimed to incorporate these ingredients into an herbal toothpaste and test its efficacy against bacteria that cause tooth decay, such as S. mutans and E. faecalis. Extracts from betel leaf, areca nut, aromatic ginger, gambier sap, and clove buds were used in this study. Based on variations in extract concentrations, three formulations were developed: F1, F2, and F3. In addition, F0 was the toothpaste base. The herbal toothpaste was light brown in color, homogeneous, semisolid, and had a characteristic betel leaf aroma, according to the evaluation results. The final product had a pH of 7.52–8.59, viscosity of 238.9–242.3 cP, and a foam height of 20 mm (F0), 11 mm (F1), 9 mm (F2), and 6 mm (F3). These values meet the toothpaste quality standard (SNI 112-3524-1995). While F1 showed moderate inhibition against S. mutans and E. faecalis in the antibacterial test, F2 and F3, showed high inhibition against S. mutans and moderate inhibition against E. faecalis. Based on these results, the optimal formula is F3 which has a larger inhibition diameter of 12.23 mm for S. mutans and 9.10 mm for E. faecalis. This herbal toothpaste can be developed to prevent oral candidiasis and gingivitis. Keywords: herbal toothpaste, antibacterial activity, Streptococcus mutans, Enterococcus faecalis

Phytochemicals properties and antimicrobial activities of Carica papaya and Balanites aegyptiaca’ seeds aqueous infusion and decoction extracts

Carica papaya and Balanites aegyptiaca seeds extract have several uses, from food to traditional medicine. This study aims to determine their phytochemicals compound and appreciate their antimicrobial properties against clinical strains. Polyphenolic content was determined with standard methods while DPPH radical scavenging activity is used to appreciate the antioxidant properties, using ascorbic acid as standard. Antimicrobial activities were performed according to the inhibition diameters, using agar diffusion method. Minimum inhibitory concentrations and Minimum fungicidal concentrations were established based on broth dilution methods. The extraction yield is ranged between 6.3 and 20.3%. The results shown polyphenolic content varying from 1256.13±21.09 to 2315.81±53.52 µg GAE/100 mL for Carica papaya and from 303.98±0.93 to 948.06±3.23 µg GAE/100 mL for Balanites aegyptiaca while the antioxidant activity is ranged between 31.76±2.35 and 58.47±4.24 µg AEAC/100 mL for Carica papaya and from 29.80±0.32 to 78.44±2.81 µg AEAC/100 mL for Balanites aegyptiaca. Infusion’s extracts always have the highest values of polyphenols content and antioxidant activity than decoction extracts, be it papaya or balanites seeds. Neitheir flavonoids content nor antibacterial activity was found. The inhibition diameter varies from 14.5±0.5 to 40.5±0.5 mm for papaya seeds extracts and from 16.5±0.5 to 21.0±0.5 mm for balanites seeds extracts without a significative effect of mixture for both extracts. MICs vary from 11.71±0.1 to 75.0±0.0 mg. mL-1 for Carica papaya seeds extracts with 11.72±0.2 to 37.30±0.2 mg. mL-1 and 18.74±0.1 to 100±0.0 mg.mL-1 for Balanites aegyptiaca. Mixture extracts presented intermediaire values. Decoction extracts have lowest MICs values and infusion reveals itself to be the sweetable aqueous extraction techniques but the appropriate infusion time need to be highlight.&#x0D; Keywords: Carica papaya, Balanites aegyptiaca, Seeds extracts, Phytochemical, antifungal

Experiment to Demonstrate Pesticide-Induced Antimicrobial Resistance (AMR): An Emerging Health Threat.

Background Pesticides, including insecticides, herbicides, and fungicides, are essential for global food production, boosting crop yields, and preventing disease transmission. However, their excessive and improper use raises concerns about potential long-term consequences, affecting microbial ecosystems and fostering antimicrobial resistance. Materials and methods The objective of the study was to identify the effect of the pesticide compound (Imidacloprid17.1% w/w) on the ATCCEscherichia coli. An experiment was conducted on ATCCEscherichia coli27852. A 0.5 McFarland suspension of the strain was incubated in the presence of a pesticide compound (Imidacloprid17.1% w/w) at a dilution of 1:4, 1:8, and 1:16. at 370C. Antibiotic susceptibility for cefoxitin, ciprofloxacin, ceftazidime, amikacin, and imipenem was determined via the Kirby-Bauer disk diffusion test at intervals of 24 hours, 48 hours, seven days, and 21 days. The results were then compared to the standard zone of inhibition diameter for ATCCEscherichia coli27852 by Clinical and Laboratory Standards Institute (CLSI) guidelines. Results No bacterial growth was detected at pesticide dilutions of 1:1 and 1:2, indicating their inability to tolerate high pesticide concentrations. However, growth became evident at a 1:4 dilution and beyond, with mutants thriving within the inhibition zone. The experiment caused significant alterations in the inhibition zone sizes for all antibiotics, especially notable with imipenem, amikacin, and ceftazidime compared to the initial zone size for ATCCEscherichia coli27852. Conclusion Our study concludes that the pesticide (Imidacloprid 17.1% w/w) significantly influences antibiotic resistance, especially with carbapenems, aminoglycosides, and cephalosporins in the tested groups at various concentrations and durations of exposure.

The Effect of Chlorogenic Acid in Green Arabica Coffee Beans on the Activity of Staphylococcus aureus

Background: Gingivitis is a dental and oral health problem caused by the bacteria Staphylococcus aureus. This research utilized the antibacterial effect of the chlorogenic acid compound content of green Arabica coffee beans (Coffea arabica L.) on the activity of the Staphylococcus aureus bacteria. The aim of the research was to determine the effect of chlorogenic acid from green Arabica coffee beans and its inhibitory diameter on the activity of Staphylococcus aureus bacteria.&#x0D; Methods: The research method used was laboratory experimental with post-test only with a control group design. The research samples were green Arabica coffee bean extract with various concentrations of 25%, 50%, 75%, and 100%, which is compared to various concentrations of pure chlorogenic acid (95% Sigma-Aldrich). The chlorogenic acid content in the extract was analyzed with liquid chromatography LC-MS/MS. The large sample was determined using the Federer formula with a total sample size of 24 samples. The parameter measured was the diameter of the growth inhibition zone for Staphylococcus aureus bacteria. Data were analyzed statistically using One-way ANOVA and Post Hoc LSD, and the research results were shown in regression graphs.&#x0D; Results: The results of the analysis of chlorogenic acid content of green arabica coffee bean extract amounted to 4.29% The results of this study showed that the average diameter of the inhibition zone of green Arabica coffee bean extract with concentrations of 25%, 50%, 75% and 100% on the growth of Staphylococcus aureus bacteria was 7.65 ± 0.289 mm; 9.63 ± 0.550 mm, 10.50 ± 0.374 mm, and 12.75 ± 0.370 mm. Research shows that the higher the concentration of green Arabica coffee bean extract, the larger the diameter of the inhibition zone. 95% pure chlorogenic acid from Sigma-Aldrich displays an inhibition zone above 12.5%.&#x0D; Conclusion: Chlorogenic acid exerts a substantial inhibitory impact on the proliferation of Staphylococcus aureus bacteria.

Mycoplasma and Neisseria Prevalence in Asymptomatic Women and Investigation of their Susceptibility to Tamarindus indica and Syzygium aromaticum Aqueous Extracts

Neisseria and Mycoplasma are two prevalent bacteria in the female urogenital tract leading to gynecological infections and infertility. The aim of this study was to assess the antibacterial activity of Tamarindus indica and Syzygium aromaticum extracts against Neisseria and Mycoplasma isolates. It was a cross cectional study on 60 asymptomatic women at the Protestant and Regional Hospital of Ngaoundere. For this reason, a large consecutive sample of patients with several well-defined characteristics was assembled and urine and cervical-vaginal swab were collected using standard procedures. After being isolated on a specific medium, several strains of Neisseria and Mycoplasma were identified based on their morphological and biochemical characteristics. The antibacterial activity of the plant extracts was tested using the agar-well diffusion method. It was discovered that 70% of asymptomatic women had overall infection, with varying prevalence rates. The prevalence rates of Neisseria and Mycoplasma were 14.29% and 85.71% respectively. The aqueous extracts of Syzygium aromaticum against Neisseria produced inhibitory diameters of 43 mm, 40 mm and 32 mm at doses of 20 mg/mL, 10 mg/mL, and 5 mg/mL, respectively while, at the same doses, the aqueous extract of Tamarindus indica produced inhibitory diameters of 16 mm, 14 mm and 13 mm, respectively. The combined extract of Syzygium aromaticum and Tamarindus indica exhibits inhibitory diameters of 25, 23, and 30 mm at 20 mg/mL, 10 mg/mL, and 5 mg/mL, respectively. Syzygium aromaticum extract alone showed efficacy against Mycoplasma, with diameters of 16.5 mm, 13 mm and 10.5 mm at concentrations of 20 mg/mL, 10 mg/mL, and 5 mg/mL respectively. Inhibition diameters of 18 mm (for fosfomycin and ofloxacin), 22 mm (for chloramphenicol and ceftriaxone) and 26 mm (for levofloxacin) were found using Neisseria isolates. The only drugs that demonstrated efficacy against Mycoplasma were Minocycline and Josamycin. Given these findings, extracts of Syzygium aromaticum and Tamarindus indica can be investigated and used to treat infections caused by Niesseria and Mycoplasma.

In vitro and in silico Studies: Penicillin-Binding Protein 2a (PBP2a) Inhibition by Stigmasterol in Banyan Hanging Roots (Ficus benjamina L.) as Novel Treatment of Methicillin-Resistant Staphylococcus aureus (MRSA)

The most common cause of nosocomial infection worldwide is caused by Gram-positive coccus bacteria or what we commonly call Methicillin-resistant Staphylococcus aureus (MRSA). This study aimed to find novel antimicrobial agents from the banyan tree (Ficus benjamina L.) hanging roots to treat MRSA. Docking experiment and well diffusion were used as in silico and in vitro experiments respectively to identify the potential of stigmasterol against MRSA. The data were analyzed statistically with one-way variance analysis (ANOVA), post-doc Tukey assay, correlation, and regression by SPSS Amos 24. In the in silico experiment, stigmasterol was strongly associated with penicillin-binding protein 2a (PBP2a) on the active side of LYS289. Thus, it had the potential to inhibit PBP2a. Disruption of cell walls, the release of cytoplasmic contents, and a decrease in the cellular volume of MRSA were caused by the inhibition of PBP2a. The well diffusion test results showed the inhibition zone in 50 - 100 μg/ml of stigmasterol against MRSA. The inhibition zone was in the range of 7.38 – 10.17 mm. The inhibition diameter indicated a significant difference with a p-value &lt; 0.05. The results of statistical analyses indicate that stigmasterol is effective as an antimicrobial against MRSA. Stigmasterol has potential as a potential microbial agent for the therapy of MRSA.

Susceptibility of some Enterobacteriaceae isolated from 4 different aquatic environments in DR Congo (Central Africa), to Amoxicillin/Clavulanic acid and some 3rd generation Cephalosporins

Little is known about the variation of the antibiotic susceptibility of different bacterial strains of the same cells species, isolated from different aquatic environments. The present study aims to evaluate the susceptibility towards some 3rd generation cephalosporins (Ceftriaxon, Ceftazidim and Cefotaxim) and Amoxicillin/Clavulanic acid, of Enterobacteriaceae strains isolated from groundwater, stream, hospital wastewater and slaughterhouse wastewater. Enterobacteria species were isolated on Mac Conkey agar, then identified using enzymatic and MALDI-TOF MS system. The antimicrobial susceptibility was carried out using the disk diffusion method. The antibiotic minimum inhibitory concentrations (MICs) were carried using the VITEK®2 system. Bacterial species mostly identified were Klebsiella pneumoniae, Escherichia coli, Salmonella typhi and Ewingelia americana. The antibiotic inhibition diameters and the MICs varied depending on the antibiotics, bacterial species and type of aquatic environment hosting the microorganism. Relatively lower MICs were recorded with Cefotaxim against different bacteria in slaughterhouse wastewater, in river water and in well water. Antibiotic resistance was noted with all strains from hospital wastewater. Significant differences (P˂0.05) amongst antibiotic inhibition diameter was noted for K. pneumoniae and S. typhi in most cases. The relative variations in the action mechanisms amongst antibiotics and the intrinsic defense potential of each bacterial strain, as well as the potential influence of the physicochemical properties of each water medium, could partly be at the origin of the relative differences observed at the phenotypic level. It seems necessary to explore the diversity, similarities and differences amongst antibiotic resistance genes in these different types of aquatic biotopes.

Comparative Analysis of the Inhibitory Efficacy of 50% and 80% Concentrations of Rambutan Seed Extract (Nephelium lappaceum L.) on the Growth of Candida albicans

Introduction. Denture stomatitis is a prevalent issue among those who wear dentures, and it is caused by Candida albicans. Ketoconazole, an azole antifungal medication, is commonly employed to treat denture stomatitis. However, it is important to note that the usage of this agent might lead to hepatotoxicity and the development of resistance. The objective of the study was to assess the inhibitory efficacy of rambutan seed extract (Nephelium lappaecum L.) at concentrations of 50% and 80% on the proliferation of Candida albicans.&#x0D; Methods. This research employs a laboratory experiment using a design that includes a post-test only control group. The specimen is an uncontaminated culture isolation of Candida albicans. This study had four distinct groups: rambutan seed extract concentrations of 50% and 80%, a positive control group, and a negative control group. Each group was reproduced six times. Using digital calipers to measure the diameter of resistance. Upon completion of data collection, the acquired data was subsequently subjected to analysis utilizing one-way ANOVA and post hoc LSD statistical testing.&#x0D; Results. The research findings indicate that the average ± standard deviation inhibitory diameter of rambutan seed extract was 50%, 80%, and the positive control for the growth of Candida albicans was 8.68 ± 0.585; 12.38±0.505; 22.43 ± 0.809 mm, respectively. In contrast, the negative control (DMSO) did not exhibit any inhibitory effects. The one-way ANOVA test revealed a statistically significant difference in the mean inhibitory diameter of rambutan seed extract at concentrations of 50% and 80% on the growth of Candida albicans (p=0.000; p?0.05). The findings of the LSD post hoc test indicated a significant difference in inhibitory power between the 50% and 80% concentrations of rambutan seed extract, as well as between these concentrations and both the positive and negative controls. Additionally, there was a significant difference in the growth of Candida albicans between the 50% and 80% concentrations of rambutan seed extract (p?0.05).&#x0D; Conclusion. The research findings indicate that the extract derived from rambutan seeds effectively inhibits the development of Candida albicans. An 80% concentration is the optimal concentration for maximum effectiveness.