Tube Dilution Method Research Articles

Microbiological Characteristics of Beef Sausage Enriched With Roselle (Hibiscus sabdariffa L.) Sepal Extract

ABSTRACTAdding plant extracts to sausage and other meat products is very important to improve their quality, safety, and durability. The aim of this study was to evaluate the microbiological properties of beef sausage enriched with roselle (Hibiscus sabdariffa L.) sepal extract. The total content of phenolic and flavonoid compounds in hydroalcoholic extract of Roselle sepals was measured by Folin‐Ciocalteu test and aluminum chloride colorimetric method, and antioxidant activity was measured by DPPH method. Pectin was used to encapsulate the extract. The characteristics of capsules, including particle size, zeta potential, and capsule efficiency were measured. Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of extracts were performed by tube dilution method. Microbial tests were performed on sausage treatment samples. Analysis of the obtained data was done using SPSS and Excel software. The study revealed that the total phenolic and flavonoid compounds in the extract were 174.6 mg of gallic acid per gram and 16.8368 mg of quercetin, respectively. The extract displayed the highest antioxidant activity at elevated concentrations. Particle size ranged from 16.833 to 640.534 μm. The zeta potential and capsule efficiency were found to be satisfactory. Compared to the encapsulated extract, the free roselle extract better inhibited Staphylococcus aureus (s. aureus), Salmonella typhimurium (S. typhimurium), and Escherichia coli (E.coli). During storage until day 20, these bacteria did not grow in the free or encapsulated extract groups. However, S. aureus appeared in the free extract group from day 25 and the encapsulated extract group from day 20. Roselle extract has antimicrobial properties that can improve the quality and safety of beef sausage during storage.

Synthesis, Molecular Docking, and Biological Evaluation of Novel Indole-triazole Conjugates.

Indole-triazole conjugates have emerged as promising candidates for new drug development. Their distinctive structural characteristics, coupled with a wide array of biological activities, render them a captivating and promising field of research for the creation of novel pharmaceutical agents. This study aimed to synthesize indole-triazole conjugates to investigate the influence of various substituents on the functional characteristics of indole-triazole hybrids. It also aimed to study the binding modes of new hybrids with the DNA Gyrase using molecular docking studies. A new set of indole-triazole hybrids was synthesized and characterized using various physicochemical and spectral analyses. All hybrids underwent in-silico pharmacokinetic prediction studies. The antimicrobial efficacy of the hybrids was assessed using tube dilution and agar diffusion methods. Additionally, the in-vitro antioxidant activity of synthesized compounds was determined using the 1,1-diphenyl-2-picryl-hydrazyl free radical scavenging assay. Furthermore, in silico molecular docking studies were performed to enhance our comprehension of how the synthesized compounds interact at the molecular level with DNA gyrase. Pharmacokinetic predictions of synthesized hybrids indicated favourable pharmacokinetic profiles, and none of the compounds violated the Lipinski rule of five. Notably, compound 6, featuring a cyclohexanol substituent, demonstrated superior antimicrobial and antioxidant activity (EC50 value = 14.23 μmol). Molecular docking studies further supported the in vitro antioxidant and antimicrobial findings, revealing that all compounds adeptly fit into the binding pocket of DNA Gyrase and engaged in interactions with crucial amino acid residues. In summary, our research underscores the efficacy of molecular hybridization in shaping the physicochemical, pharmacokinetic, and biological characteristics of novel indole-triazole derivatives.

Enhanced Antibacterial Activity of Manuka Honey with Higher Methylglyoxal Concentration Against Staphylococcus Aureus: in vitro study

Objective This study aimed to investigate the antibacterial activity of two types of Manuka honey with varying concentrations of methylglyoxal (MGO), 70 mg/kg and 1050 mg/kg, against S. aureus in vitro. Methods Two types of Manuka honey were tested for their antimicrobial activities. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were determined using the broth tube dilution method. Results Both concentrations of Manuka honey exhibited antibacterial activity against S. aureus, with the higher concentration (1050 mg/kg) showing enhanced antibacterial effects. The MIC was 100% v/v (undiluted) for the lower concentration and 50% v/v for the higher concentration. The MBC was inferred to be at a dilution of 50% v/v for the higher concentration, but not reached for the lower concentration at the dilution levels used. Conclusion The findings suggest that Manuka honey with a higher concentration of MGO may be more effective in inhibiting and potentially killing S. aureus. The study highlights the potential use of high-concentration Manuka honey as an alternative antimicrobial agent and calls for further investigation in clinical settings.

Synergistic Effect of Pakistani Honey with Black Seeds against Food Borne Pathogens

Background: Food borne infections is a major public health problem all over the world. For centuries, honey has been used as a gastrointestinal and topical remedy and also as a food preservative. It has been exploited not only as a food but, utilized for multiple purposes such as for the treatment of various disease, for wound healing etc. Black seeds have also been used in traditional medicine and food preservation due to their effective therapeutic properties. The synergy-based combination of both the herbal extracts may enhance the antimicrobial potential against food borne pathogens. Objective: This study aims to evaluate the antibacterial potential of different variants of Pakistani honey (Acacia honey, Ziziphus honey, and Sidr honey) in combination with black seeds against foodborne pathogens. Methods: The antibacterial activity of different Pakistani honey (Acacia honey, Ziziphus honey, and Sidr honey) was evaluated using an agar well diffusion assay. The synergistic effect of honey and black seed was also examined. Moreover, the Minimum Inhibitory Concentration (MIC) was determined using the tube dilution method. Results: The combination of Ziziphus honey and black seeds showed the most significant antibacterial effect such as 25.0, 28.0- and 30.0-mm zones of inhibition against Escherichia coli, Salmonella typhi, and Staphylococcus aureus respectively. The inhibition zone of the synergistic antibacterial effect of honey and black seed extracts against foodborne pathogens was significantly larger than the extracts used separately. Furthermore, the lowest MIC was observed 3.12 mg/ml against Escherichia coli and Staphylococcus aureus in the combination of Ziziphus honey with black seeds whereas, 6.25 mg/ml was observed against salmonella typhi. Conclusion: The present finding supports the traditional use of these different Pakistani honey variants in combination with black seeds for treating food borne pathogens to promote good health without any adverse side effects. The results suggested that present combination of natural extracts could be further explored clinically as a potent synergy-based therapeutic approach for treating various multidrug resistant food pathogens.

In Vitro Biological and GC-MS Analysis of Whole Plant Calotropis procera

Calotropis procera is a medicinal, traditional, and therapeutic plant in Pakistan. In this research study, the biological activities, for instance, anticancer, antileishmanial, antibacterial, antifungal, anti-inflammatory, and brine shrimp lethality assay and GC-MS are studied. MTT assay, antileishmanial bioassay, microplate Alamar Blue assay, agar tube dilution method, oxidative burst assay using chemiluminescence technique, B-hatching techniques, and triple quadrupole acquisition method MS parameters were the methods used for anticancer, antileishmanial, antibacterial, antifungal, anti-inflammatory, brine shrimp lethality assay, and gas chromatography-mass spectrometry. Whole plant methanol extract of Calotropis procera (WMECP) inhibited 69.1% of the growth of HeLa cell line with an IC50 value of 3.1 ± 0.4 and whole plant n-hexane fraction of Calotropis procera (WHFCP) and whole plant and aqueous fraction of Calotropis procera (WAFCP) inhibited the growth by 70.2% and 65.2% with IC50 values of 5.0 ± 0.3 and 17.1 ± 1.0. Whole plant methanol extract of Calotropis procera (WMECP) inhibited 70.1% of the growth of the PC3 cell line with an IC50 value of 5.1 ± 0.3 and whole plant n-hexane fraction of Calotropis procera (WHFCP) and whole plant aqueous fraction of Calotropis procera (WAFCP) inhibited 61.6% and 59.7% with IC50 values of 3.7 ± 0.5 and 16.4 ± 1.0. None of the extract and fractions of Calotropis procera showed anticancer activities against the 3T3 cell line. None of the extract and fractions of Calotropis procera showed antileishmanial, antibacterial, antifungal, and anti-inflammatory activities. Whole plant methanol extract of Calotropis procera (WMECP) exhibited lethality at the highest concentration while other fractions did not exhibit lethality. GC-MS studies revealed that the whole plant methanol extract of Calotropis procera (WMECP) consists of 11 compounds, whole plant n-hexane fraction of Calotropis procera (WHFCP) consists of 9 compounds, and whole plant aqueous fraction of Calotropis procera (WAFCP) consists of 7 compounds.

Fuzheng Touxie Jiedu Huayu Decoction inhibits the MexAB-OprM efflux pump and quorum sensing-mediated biofilm formation in difficult-to-treat multidrug resistance Pseudomonas aeruginosa

Ethnopharmacological relevanceFuzheng Touxie Jiedu Huayu Decoction (FTJHD) is a commonly used clinical formula that has been found effective in resisting multidrug resistance-Pseudomonas aeruginosa in previous in vivo and in vitro studies. Aim of the studyTo investigate the antimicrobial effects of FTJHD and its drug-containing serum alone or in combination with ceftazidime on difficult-to-treat multidrug resistance-P. aeruginosa (DTMDR-P. aeruginosa). Materials and methodsThe antibacterial effects of FTJHD and its drug-containing alone or in combination with ceftazidime against DTMDR-P. aeruginosa were examined by the tube dilution method and bacterial growth curves. The changes in the bacterial ultrastructure were examined by transmission electron microscopy. The biofilm formation ability of bacteria was examined by crystal violet staining and scanning electron microscopy. The expression of the MexAB-OprM efflux pump and quorum sensing system genes were validated through quantitative polymerase chain reaction. Molecular docking was used to evaluate the interaction between active components and the MexAB-OprM efflux pump. ResultsFTJHD-containing serums at 1-, 2-, 4-, and 8-fold concentrations reduced the minimal inhibitory concentration (MIC) of ceftazidime against DTMDR-P. aeruginosa from 128 μg/mL to 64 μg/mL. Sub-inhibitory concentrations of ceftazidime in combination with FTJHD and FTJHD-containing serum prolonged the lag period of bacterial growth and reduced bacterial numbers. Additionally, 1/2 MIC of ceftazidime combined with FTJHD-containing serum significantly inhibited the activity of the MexAB-OprM efflux pump and quorum sensing system, thus reducing biofilm formation while causing more severe damage to the bacteria. Molecular docking revealed a strong affinity of quercetin, baicalein, luteolin, kaempferol, and β-sitosterol for the efflux pump regulatory proteins OprM and MexR. ConclusionFTJHD can exert synergistic anti-DTMDR-P. aeruginosa effects with ceftazidime by inhibiting biofilm formation mediated by the MexAB-OprM efflux pump and quorum sensing.

Eremostachys laevigata Bunge responses to different extraction solvents and methods: physiological, biochemical, and antibacterial attributes

This study examined the biochemical composition of Eremostachys laevigata Bunge's aerial and underground organs using various solvents (methanol, water, N-hexane, chloroform, and acetone) and their impact on antibacterial activity against eight bacterial strains (Escherichia coli, Staphylococcus aureus, Salmonella enterica, Pseudomonas aeruginosa, Klebsiella pneumoniae, Shigella dysenteriae, Proteus mirabilis, and Bacillus cereus). Soxhlet and maceration extraction methods were used, and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined using the tube dilution method. The study found that N-Hexane and water solvents had the highest total phenol content, while methanol, acetone, and chloroform had the lowest. Additionally, N-Hexane and methanol solvents showed the highest and lowest flavonoid content, respectively. The methanol extract from underground organs using the Soxhlet method exhibited the strongest antibacterial activity, whereas the acetone extract showed the weakest antimicrobial effect. Staphylococcus aureus displayed both the MIC and MBC, and Salmonella enterica showed the highest susceptibility to the well diffusion method, while both Escherichia coli and Staphylococcus aureus were highly susceptible to the disk diffusion method. The underground organs contained 6.87 mg.g-1 of phenolic compounds and 0.19 mg.g-1 of flavonoids. Two iridoid glycosides, pholoyoside and sesamoside, were separated from the methanol extract of the underground organs using reversed-phase HPLC. The research highlights E. laevigata Bunge's potential as a natural reservoir of antimicrobial compounds, with phenolic and flavonoid compounds, along with iridoid glycosides, presumed to contribute to its antibacterial properties.

Eco-Friendly Sanitization of Indoor Environments: Effectiveness of Thyme Essential Oil in Controlling Bioaerosol Levels and Disinfecting Surfaces.

Bioaerosols and pathogens in indoor workplaces and residential environments are the primary culprits of several infections. Techniques for sanitizing air and surfaces typically involve the use of UV rays or chemical sanitizers, which may release chemical residues harmful to human health. Essential oils, natural substances derived from plants, which exhibit broad antimicrobial properties, could be a viable alternative for air and surface sanitation. The objective of this study has been to investigate the efficacy of thyme essential oil (TEO) in environmental sanitation processes. In Vitro assays through agar well diffusion, disk volatilization and tube dilution methods revealed significant antimicrobial activity of TEO 100% against foodborne and environmental isolates, with both bacteriostatic/fungistatic and bactericidal/fungicidal effects. Therefore, aqueous solutions of TEO 2.5% and 5% were formulated for air sanitation through nebulization and surface disinfection via direct contact. Bioaerosol samples and surface swabs were analyzed before and after sanitation, demonstrating the efficacy of aqueous solutions of TEO in reducing mesophilic and psychrophilic bacteria and environmental fungi levels in both air and on surfaces. The obtained results prove the antimicrobial potential of aqueous solutions of TEO in improving indoor air quality and surface cleanliness, suggesting thyme essential oil as an effective and safe natural sanitizer with minimal environmental impact compared to dangerous chemical disinfectants.

Phytochemical Profile and Antibacterial Effects of Zingiber Officinale Root Extract on Some Enteric Bacterial Pathogens

The majority of Africans today depend either totally or partially on medicinal plants for the treatment of various diseases. In some rural communities, ethno-medicine is sometimes the only form of healthcare. Therefore, this work aimed to determine the phytochemical constituents and antibacterial potentials of Z. officinale, which is one of the medicinal plants used by some people. The active ingredients of the plant were first extracted using water and ethanol as solvents. This was followed by the phytochemical analysis of the extracts. Furthermore, the antibacterial effects of aqueous and ethanolic extracts of Z. officinale on Escherichia coli, Salmonella typhi and Shigella dysenteriae isolated from faeces of gastroenteritis patients were evaluated using the agar diffusion technique (punch method). Additionally, a two-fold tube dilution method was used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extracts. The mean values of zones of inhibition obtained were statistically analyzed using ANOVA. The least significant difference was determined according to the LSD test at P<0.05. Phytochemical analysis revealed the presence of saponin, alkaloids, flavonoids, and tannins. The antibacterial results showed that both the aqueous and ethanolic extracts have antibacterial effects against all the test organisms but at varying degrees. At the 500mg/ml concentration, the ethanolic extract of Zingiber officinale produced a zone of inhibition of 21.00b against S. dysenteriae and 20.00b against E. coli and S. typhi. On the other hand, the 500mg/ml concentration of the aqueous extract had a zone of inhibition of 20.00b against S. dysenteriae, 16.00b against E. coli and 10.00b against S. typhi. The findings from this study lend credence to the claims that Z. officinale extracts possess antibacterial potentials. Also, the higher potency in ethanolic than in aqueous extract suggests that the potency might be dose and solvent dependent. Conclusively, owing to the findings from this study, the active ingredients of Z. officinale could be harnessed and employed in the development of novel antibacterial therapies.

The impact of administration of Annona muricata leaf on estrogen and progesterone functions following mercury-induced toxicity in adult female Wistar rats

Environmental toxicants have been linked to female reproductive dysfunction resulting from oxidative stress. The study assesses the impact of ethanolic leaf extract of Annona muricata (EAM) on ovarian and uterine function following mercury-induced toxicity in female Wistar rats. The study involved 40 female Wistar rats, each weighing 114–156g, divided into eight groups of five animals each. Group A received feed and water only; group B received 500 mg/kg of EAM only; and group C received 25 mg/kg of mercury chloride (HgCl2). Groups D and E received 100 mg/kg and 500 mg/kg of EAM for 4 weeks and were treated with 25 mg/kg of HgCl2, respectively. Group F received 500 mg/kg of EAM for 4 weeks and treated immediately with co-administrstion of 25 mg/kg of HgCl2 and 500 mg/kg of EAM for 4 weeks. Groups G and H received 25 mg/kg of HgCl2 and received 100 mg/kg and 500 mg/kg of EAM for 4 weeks, respectively. Progesterone amd Estrogen levels were measured at the end of the administration. The data was analysed using SPSS version 25, with inferential statistics performed, and significant values were set at p≤0.05. Administration of mercury resulted in a decreased level of oestrogen, and progesterone. EAM treatments resulted in statistically significant increased levels of progesteron in groups E, F, G and H; group D also showed an increase, though not statistically significant. Estrogen levels were increased in groups F, G and H, but groups D and E showed a decrease in estrogen levels, though not statistically significant. The study reveals that EAM enhances female reproductive hormonal levels and may turn out into a potential capable of reversing or preventing female infertility linked to mercury chloride toxicity.

Preparation Of Mixed Ligand Complexes Of Cerium (III) Metal Using Multidentate Ligands And Investigation Of Their Physicochemical, Spectral, Thermal, And Antibacterial Properties.

This study involves the synthesis and characterization of Cerium (III) Mixed-ligand complexes employing 2-hydroxybenzaldehyde oxime (BO) as the primary ligand and organic compounds 2-amino-3-(1H-indol-3-yl)propanoic acid (L1) , 2-amino-4-(methylthio)butanoic acid (L2) , 2-amino-3-(4-hydroxyphenyl)propanoic acid (L3) , 2-Amino-3-sulfhydrylpropanoic acid (L4) as secondary ligands. The resulting complexes exhibit a brown color and display stability, as evidenced by conductometric measurements indicating non-electrolyte behavior. FTIR analysis reveals coordination through O and N donor atoms, while thermogravimetric studies highlight stability with coordinated water molecules, supported by high decomposition temperatures. UV studies demonstrate intra-ligand and ligand-to-metal charge transfer transitions. Elemental analysis confirms a 1:2:1 ratio for the complexes. Antibacterial assays using agar cup and tube dilution methods affirm the complexes' antibacterial activity against specific bacterial strains.

Test The Effect of The Inhibitory Power and Minimum Killing Power of Clove Flower Oil (Syzigum aromaticum) with Water as a Solvent Against Staphylococcus aureus

Excessive use of antibiotics in treating infectious diseases has caused some bacteria to become resistant. Therefore, it is hoped that the use of natural ingredients such as cloves can be an alternative solution in reducing excessive use of antibiotics. This study aims to test the inhibitory effect and minimum killing power of clove flower oil (Aromatic syzygum) with water as a solvent against Staphylococcus aureus. In determining the inhibition zone, the diffusion disk method was used. Meanwhile, determining the Minimum Kill Ability (MKA) uses the liquid tube dilution method. The results showed that an increase in the concentration of clove flower extract was followed by an increase in the inhibition zone in the media with the isolate Staphylococcus aureus. Meanwhile, in measuring the Minimum Kill Ability, the results showed that the MKA value of clove leaf extract against bacteria Staphylococcus aureus smaller than 5%. This shows that only a 5% concentration of clove leaf extract is enough to inhibit growth Staphylococcus aureus. These findings indicate the potential of clove leaf extract as an antimicrobial agent for bacteria Staphylococcus aureus. So it is hoped that natural ingredients will be able to reduce excessive use of antibiotics.

THE ANTIFUNGAL EFFECTIVITY TEST OF ETHANOLIC EXTRACT OF KIDNEY BEAN (PHASEOLUS VULGARIS L.) AGAINST CANDIDA ALBICANS USING IN VITRO METHOD

Introductions: Candida albicans can causes an infection called candidiasis. Kidney beans (Phaseolus vulgaris L.) are natural products that contain several active compounds such as saponins, flavonoids, tannins, and coumarins that can damage the membrane and cell wall of Candida albicans. Methods: The design of this study used true experimental post control design only with the tube dilution method. Extract concentrations used were 3200 mg/ml, 3600 mg/ml, 4000 mg/ml, 4400 mg/ml, 4800 mg/ml, 5200 mg/ml, 5600 mg/ml, and 6000 mg/ml. This study used a negative control (extract 0%) and a positive control (Nystatin 1%), each of which was added with Candida albicans. Results: The results showed that the Minimum Inhibitory Concentration (MIC) was obtained at 5200 mg/ml and the Minimum Bactericidal Concentration (MBC) was obtained at 6000 mg/ml. One Way ANOVA statistical test results showed a significant difference (significance value 0,000; p< 0.05). Pearson correlation test showed the direction of the negative correlation (r = -0.945; p <0.01). Discussion: The ability of ethanolic extract of kidney bean to inhibit growth and kill the Candida albicans is due to the active compounds contained in it, namely flavonoids, saponins, tannins, and coumarin. Flavonoids can cause protein denaturation. Saponins have the ability to kill Candida albicans by forming pores in the double lipidic layer that results on the loss of cell integrity. Tannins have the ability to inhibit fungal growth by inhibiting the synthesis of chitin and damaging cell membranes. Coumarins can cause fungal death by interfering with cell wall synthesis. Conclusions: The conclusion of this research is the ethanol extract of kidney bean can inhibit at the concentration of 5200 mg/ml and kill the growth of Candida albicans at the concentration of 6000 mg/ml.

Synthesis, biological evaluation and in silico studies of some new analogues of 3,5-vdisubstituted thiazolidin-2,4-dione.

Background: A new series of 3,5-disubstituted thiazolidin-2,4-dione molecules werederived and characterized using various spectral techniques (1H NMR, IR, carbon, hydrogen, nitrogen, etc.) and physicochemical parameters. Materials & methods: The molecules were derived using Knoevenagel condensation followed by Mannich reaction and further synthesized analogues were screened for their antioxidant and antimicrobial potential using 2,2-diphenyl-1-picrylhydrazyl free radical scavenging method and serial tube dilution method, respectively, along with in silico studies (docking and absorption, distribution, metabolism and excretion parameters) to explore the drug-receptor interaction and druglikeness. Results & conclusion: In antimicrobial screening, the analogs MP2, MM6, MM7 and MM8 displayed promising activity while molecule MM4 exhibited better antioxidant potential in the series. In molecular docking analysis, the best-fitted analogs, namely, MM6 and MM7, showed good interactions.

Antimicrobial Activities of Some Constituents Isolated from a Kenyan Medicinal Plant, Capparis fascicularis DC

Background of the Study. Capparis fascicularis DC. is an indigenous medicinal plant belonging to the family Capparaceae found in Nyandarua County, Nairobi, Kenya, and many parts of Africa. It is a shrub whose roots are used traditionally to treat colds. Aim. The aim of the present study is to carry out antimicrobial activities of solvent extracts of different parts of Capparis fascicularis, characterize the phytochemical constituents of the most active extract, and identify the most active compounds. Place and Duration of the Study. All the experiments were carried out in the departments of Chemistry and Microbiology, Kenyatta University, Nairobi, Kenya. Methodology. Petroleum ether, ethyl acetate, methanol, and water extracts from the leaves, stem bark, and root bark of C. fascicularis were screened against selected strains of both Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Salmonella typhimurium and Escherichia coli) bacteria using disc diffusion and tube dilution methods. Fractionation of the most active crude extract was carried out by column chromatography, and the fractions together with the most active crude extract were screened against the selected bacterial strains. The most active fraction was further fractionated, and the subfractions were screened against the bacterial strains to test for possible synergistic effects between the subfractions and their constituents. The most active fraction was then analysed by GC-MS and LC-ESI-MS methods to identify the major constituents. Results. The ethyl acetate extract of C. fascicularis root bark (CFR2) showed a significant in vitro antibacterial activity. From the seven fractions of CFR2 obtained, fraction 2 (F2) had the lowest MIC value and was thus most active. Moreover, F2 was found to be more active compared to the four subfractions obtained from it. This suggested that constituents of F2 worked in synergy. Fraction 2 contained phenols, terpenes, and flavonoids. Two compounds were identified by GC-MS as 2,4-di-tert-butylphenol and (E,E)-2,4-decadienal, while three compounds were identified by LC-ESI-MS as tanshinone II A, cryptotanshinone, and danshensu. Conclusion. The study revealed that CFR2 is the most active extract on bacteria, suggesting that most antimicrobial compounds are concentrated in the roots of C. fascicularis. A follow-up study is directed towards chromatographic separations to obtain the other chemical constituents and screen them against various strains of bacteria.

In Vitro Antibacterial Activities of Selected Medicinal Plants Against Diarrhoea Causing Pathogens

Diarrhea has been a major cause of death, especially among children in developing countries. Traditional preparations of medicinal plants with antimicrobial activities have been extensively used in West African regions. This study was conducted to determine the antibacterial activities of selected medicinal plants against pathogens that cause diarrhea. Fresh leaves of three medicinal plants, namely Anogeissus leiocarpus, Vernonia amygdalina, and Piliostigma thonningii, were collected in Minna, Niger State. Pathogens causing diarrhea (Vibrio cholerae, Klebsiella pneumoniae, and Salmonella enterica serovar) were isolated and identified from stool samples of individuals suffering from diarrhea. The plant material was extracted using the maceration technique with methanol. The antibacterial effectiveness of the selected plant extracts was evaluated using the agar well diffusion method on Muller Hinton agar. The minimum inhibitory concentration was determined using the Broth tube dilution method, while the minimum bactericidal concentration was determined by plating out on nutrient agar plates with no visible growth. The results indicated that all plant extracts effectively suppressed the microbial growth of diarrhea-causing bacteria with varying potency. Among them, the extract of Anogeissus leiocarpus consistently exhibited the largest inhibitory zone diameters across all three bacterial strains at a concentration of 300 mg/mL (Vibrio cholerae: 32.33 mm, Klebsiella pneumoniae: 34.00 mm, and Salmonella enterica serovar Kentucky: 36.33 mm). This extract can be considered the most active. For Anogeissus leiocarpus, the MIC values ranged from 0.19 to 0.96 mg/mL, and the MBC values ranged from 0.20 to 1.09 mg/mL. For Vernonia amygdalina, the MIC values ranged from 0.96 to 1.80 mg/mL, and the MBC values ranged from 1.20 to 1.920 mg/mL. The results of this study validate the traditional use of these plants in medicine. However, further studies, including the isolation and identification of active compounds would be necessary to fully understand the mechanisms behind the observed antimicrobial effects.

Antimicrobial Effects of Annona squamosa Leaf Extract on Staphylococcus aureus Growth: An In Vitro Study

Introduction: Mastitis is inflammation of the breast tissue due to infection with the Staphylococcus aureus bacteria causing local infections. It takes the natural ingredient Annona squamosal extract as an antimicrobial. Purpose: to determine the effectiveness of Annona squamosa leaf extract on the inhibition and killing power of Staphylococcus. Method: Experimental laboratory research with antibacterial activity test. Tube dilution method by incorporating bacteria and extracts with concentrations of 20%, 22.5%, 25%, 27.5%, 30%, and 32.5% and then measuring the MIC. The diffusion method is carried out by planting bacteria in a Nutrient Agar Plate and then giving the extract with 6 concentrations to calculate the MBC. Results: The results of the One-Way ANOVA test obtained a significance value of (p<0.001), indicating that changes in the concentration of Annona squamosa made a significant difference to Staphylococcus. The correlation test showed a significant p-value of (p<0.001), which means that there was a significant relationship between the administration of extract and the number of Staphylococcus. Conclusion: Annona squamosa leaf extract is able to significantly inhibit the growth of Staphylococcus bacteria and the higher the concentration of Annona squamosa leaf extract, the fewer the number of bacterial colonies that grow.

New Benzopyrrole Derivatives: Synthesis and Appraisal of Their Potential as Antimicrobial Agents.

A series of twenty compounds (23-42) were synthesized and characterized by spectral studies in order to explore newer antimicrobial compounds. The majority of the synthesized compounds reported significant antimicrobial properties against various pathogenic bacterial and fungal strains with the help of tube dilution method. Significant activities (MIC ranging from 3.9 to 15.62 μg/ml) have been shown against Gram-negative and Gram-positive bacteria with. In contrast, moderate to outstanding antibacterial activity was reported versus Gram-negative bacteria such as E. coli and P. aeruginosa along with Gram-positive bacteria such as S. aureus and B. subtilis. While antifungal activity was moderate to excellent against two fungus strains (Candida tropicalis, Candida glabrata). Compounds 25 and 34 had the utmost activity versus Gram-positive and Gram-negative bacteria too. The antifungal activity of compound 35 was comparable to that of standard. In-silico Molecular docking evaluations were performed for antibacterial and antifungal activities against the target DNA gyrase A (PDB: 1AB4) and 14 alpha-sterol demethylase enzyme (PDB: 1EA1), respectively. The dock score for typicals compounds for antibacterial and antifungal activity were -4.733 and -9.4, respectively. The three-dimensional QSAR examination was carried out by multiple linear regression (SA-MLR) with good predictive power (r2=0.9105, q2=0.8011). Establishment of several interactions between the ligand 25 and 34 and the active site of residue of both receptors, enable the ligand 25 and 34 to be fit well in the pocket of the active site, as seen in Molecular dynamics simulations analysis. Thus, data suggest that these ligands could be further explored as potential precursors to develop antimicrobial drugs.

Design, Synthesis and Biological Screening of Novel Carbazole Tethered Oxyethylamino Derivatives as Antimicrobial Agent

Abstract: Background: Carbazole is an important scaffold known to be associated with several biological activities including antimicrobial activities. Incorporation 4-oxothiazolidine moiety in carbazole moiety may lead to a new series of antimicrobials compounds. Aim: In this study, design and synthesis of novel carbazole tethered oxyethylamino was started with carbazole as basic pharmacophore and evaluated for antimicrobial activity. Materials and Methods: Molecular docking of carbazole derivatives was carried out by Schrödinger (Maestro 10.5v) active compound were Synthesized and screened for in vitro antimicrobial activity against Candida albicans and gram-positive and gram-negative bacterial strains such as Staphylococcus aureus, Bacillus subtilis, E. coli. MIC was calculated by standard agar tube dilution method. Results: All Compounds shown good antimicrobial activity at 25 (μg/ml) – 510 (μg/ml). The molecular docking studies demonstrated ligand protein interaction. Conclusion: carbazole represent novel set of lead for the designing of novel antimicrobial agents. Keywords: Molecular Docking, Carbazole, Oxyethylamino, Antimicrobial activity, Antifungal activity.

Comparison of Methanolic Extract of Piper Betle to Amikacin against the Growth of Pseudomonas aeruginosa

Pseudomonas aeruginosa is one of the most common pathogens that cause Healthcare-Associated Infections (HAIs). A previous study stated that Piper betle L. extract has antibacterial activity against certain bacteria, including Pseudomonas aeruginosa. This study has the objective of comparing antibacterial activity of the methanolic extract of Piper betle L. and amikacin on the growth of Pseudomonas aeruginosa. This study used the tube dilution method with a sample of Pseudomonas aeruginosa from Microbiology Laboratory Dr. Saiful Anwar General Hospital, Malang. The results of this study showed that the value of MIC and MBC from the methanolic extract of the Piper betle L. treatment was 4800μg/mL. Meanwhile, the amikacin treatment resulted in 0.4μg/mL for MIC and 0.45μg/mL for MBC. From linear regression, it was found that the methanolic extract of Piper betle L. had a β-coefficient value closer to -1 compared to amikacin. Therefore, it can be concluded that the methanolic extract of Piper betle L. has a greater inhibiting effect on the growth of Pseudomonas aeruginosa.