Antimicrobial and Antihypercholesterolemic Activities of Pulicaria gnaphalodes

Multidrug resistance has increased globally in the communities. Bacterial infections associated with health care have weakened the existing antimicrobial therapy and demand the search for alternative therapies. In the present investigation, the medicinal plant Pulicaria gnaphalodes from Quetta, Pakistan, has been screened for antimicrobial potential. In vitro antimicrobial efficacy of P gnaphalodes extracts (methanol and ethanol) was quantitatively evaluated on the basis of zone of inhibition against different bacteria and minimum inhibitory concentration (MIC). In vivo, antihypercholesterolemic activity is determined in different rat groups. The results of the study indicated that the ethanol extract of P gnaphalodes showed maximum zone of inhibition for Bacillus subtilis of 12.1 ± 1.1 mm from all others. The methanol extract showed maximum zone of inhibition for Staphylococcus aureus of 11.9 ± 1.0 mm and rifampicin showed maximum zone of inhibition of 23.1 ± 0.9 mm. The results of ethanol and methanol extract of P gnaphalodes against different bacteria revealed that this plant has greater antimicrobial activity. However, the plant extract shows nonsignificant antihypercholesterolemic activity. The extract of this plant can be utilized as medicine to inhibit several infections caused by some bacterial pathogens found in human body.

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Assessment of antimicrobial activity of Cola milleni seed and pulp extracts against Staphylococcus aureus, Escherichia coli and Penicillium notatum

Bayero Journal of Pure and Applied Sciences ◽

10.4314/bajopas.v12i1.12s ◽

2020 ◽

Vol 12 (1) ◽

pp. 71-75

Author(s):

A.M. Aliyu ◽

S.J. Oluwafemi ◽

S. Kasim

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antimicrobial Activity ◽

Minimum Inhibitory Concentration ◽

Inhibitory Concentration ◽

Ethanol Extract ◽

Bioactive Components ◽

Zone Of Inhibition ◽

Penicillium Notatum ◽

Standard Techniques

All over the world, hundreds of plants have been identified based on researchers and experimental evidence as good sources of medicinal agents. The bioactive components (phytochemicals) of both the seeds and pulp of Cola milleni were extracted using ethanol as solvent. The bioactive components detected were alkaloids, tanins, saponins, cardiac glycosides, carbohydrates, sterols, resins and terpenes while Flavonoids, anthraquinones, anthracyanides and phenol were not detected for both the seed and pulps. Antimicrobial activity of the ethanol extract (Seed and pulp) against Staphylococcus aureus, Escherichia coli and Penicillium notatum was carried out using standard techniques. Staphylococcus aureus had the highest zone of inhibition for pulp having a range of 9.7mm±0.58mm - 19.7mm±2.52mm while Penicllium notatum had the least with 0.00mm. S.aureus also had the highest zone of inhibition range of 14.3mm±2.08mm - 21.3mm±1.53mm for the seed extract while penicillium had the least inhibition range of 5.0mm±1.00mm - 5.7mm±0.58. E.coli showed the highest minimum inhibitory concentration with ethanol extract of the pulp (160mg/ml) while penicillium notatum was not reactive. The minimum inhibitory concentration of seed against penillium notatum was the highest (160mg/ml) while staphylococcus aureus showed the lowest of 40mg/ml. The antimicrobial activity is as a result of the presence of phytochemicals detected, which suggest the use of the plant for the treatment of diseases caused by these organisms. Key words: Cola millenii, Phytochemical, Antimicrobial activity, Bacteria, Fungi

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Evaluation of the antimicrobial activity and safety of Rhus vulgaris (Anacardiaceae) extracts

BMC Complementary Medicine and Therapies ◽

10.1186/s12906-020-03063-7 ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Angela Mutuku ◽

Lizzy Mwamburi ◽

Lucia Keter ◽

Joyce Ondicho ◽

Richard Korir ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Antimicrobial Activity ◽

Methanol Extract ◽

Skin Irritation ◽

Toxicity Testing ◽

Oral Toxicity ◽

Traditional Use ◽

One Way Anova

Abstract Background Medicinal plants have been used in the treatment of various ailments in most developing countries. Oral infections are the most prevalent diseases in man. The Rhus family has been found to have antimicrobial, antimalarial, and anti-inflammatory properties. Few studies have been done on Rhus vulgaris Meikle. A study was conducted to determine the effect of Rhus vulgaris Meikle stem bark extracts against selected oral pathogenic microorganisms and the safety of the extracts in vitro and in vivo. Methods Methanol:dichloromethane (1:1), methanol and aqueous extracts were tested for bacteriostatic and bactericidal effects against Methicillin Resistant Staphylococcus aureus (MRSA), Staphylococcus aureus, Streptococcus mutans and Candida albicans. Cytotoxicity of the active extracts was determined using Vero E6 cell lines while safety was evaluated in mice and rats. Phytochemical screening was performed on the methanol extracts. One-way ANOVA and Tukey’s multiple comparisons tests were performed using IBM SPSS statistics 20.0 for antimicrobial assay and acute toxicity testing. One-way ANOVA and Dunnett’s multiple comparison tests were conducted using GraphPad Prism 8.0 for cytotoxicity assay. Results Methanol extract of Rhus vulgaris showed significant antimicrobial activity against MRSA (12.00 ± 0.00 mm; p-value of < 0.005; Minimum Inhibitory Concentration of 0.391 mg/ml; Minimum Bactericidal Concentration of 1.563 mg/ml). The extract were not cytotoxic at 100 μg/ml which was the highest tested concentration. In acute dermal irritation testing, the methanol extract resulted in mild irritation with erythema and flaking that cleared within 8 days. There were no observable adverse effects from oral administration of the extracts (acute oral toxicity testing) at concentrations of 50 mg/kg, 300 mg/kg and 2000 mg/kg. Tannins, saponins, flavonoids, terpenoids, glycosides, alkaloids and phenols were detected in the methanol extract. Conclusions Antimicrobial activity of R. vulgaris extracts supports its traditional use as a toothbrush. Cytotoxicity demonstrated by the extracts as well as the mild skin irritation warrants further study before R. vulgaris can be recommended for the development of effective and safe mouthwashes.

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AKTIVITAS ANTIBAKTERI EKSTRAK METANOL BATANG BIDARA LAUT (Strychnos ligustrina) TERHADAP BAKTERI PATOGEN

JURNAL BIOLOGI TROPIS ◽

10.29303/jbt.v19i1.1040 ◽

2019 ◽

Vol 19 (1) ◽

Author(s):

Edy Kurniawan ◽

Dwi Soelistya Dyah Jekti ◽

Lalu Zulkifli

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antibacterial Activity ◽

Pathogenic Bacteria ◽

Inhibitory Concentration ◽

Methanol Extract ◽

Klebsiella Pneumonia ◽

E Coli

Abstract : Strychnos ligustrina stem has been empirically used by the people of West Nusa Tenggara and Bali in the treatment of malaria, tooth ache and diarrhea, but there is no scientific data that supports it. This study aims to determine and prove the antibacterial activity of Strychnos ligustrina methanol extract to pathogenic bacteria in vitro and in vivo. This research is an experimental study conducted by measuring the inhibition zone (mm) growth of pathogenic bacteria, determining minimum inhibitory concentration (MIC) and minimum killing concentration (MKC) in vitro, and determining the percentage of antibacterial activity of methanol extract of S. ligustrina stem in vivo. The experiment was conducted using 4 groups of concentrations of S. ligustrina stem methanol extract in an in vitro study of 25, 50, 75, and 100% with ciprofloxacin as a positive control and aquadest as a negative control. In vivo studies experiments were carried out using 6 treatment groups of test animals male mice Balb / c (Mus musculus). The in vitro test results showed that methanol extract of S. ligustrina stems was able to inhibit the growth of pathogenic bacteria with medium categories of clinical isolates of Staphylococcus aureus and categories of weaks to Klebsiella pneumonia and Escherichia coli isolates. The minimum inhibitory concentration (MIC) for S. aureus and K. pneumonia bacteria isolates was at a concentration of 25% while for E. coli isolates at a concentration of 30%. The methanol extract of the S. ligustrina stem has no killing power against the pathogenic bacteria tested. Antibacterial activity in vivo was able to inhibit the growth of S. aureus pathogenic bacteria by 6.60% (at 25% concentration), 8.62% (at 50% concentration), and 17.31% (at 100% concentration), against K. pneumonia was 11.85% (at 25% concentration), 51.21% (at 50% concentration), and 65.92% (at 100% concentration), against E. coliat 19.18% (at concentration 25%), 29.98% (at 50% concentration), and 40.88% (at 100% concentration). Methanol extract of S. ligustrina stem proved to have antibacterial activity in vitro and in vivo. Key words: Srychnos ligustrina, pathogenic bacteria, antibacterial, in vitro, in Vivo. Abstrak : Strychnos ligustrina secara empiris telah digunakan oleh masyarakat Nusa Tenggara Barat dan Bali dalam pengobatan penyakit malaria, sakit gigi, dan diare, tetapi belum ada data ilmiah yang mendukung. Penelitian ini bertujuan untuk menentukan dan membuktikan aktivitas antibakteri ekstrak metanol batang bidara laut terhadap bakteri patogen secara in vitrodan in vivo. Penelitian ini merupakan penelitian eksperimental yang dilakukan dengan mengukur zona hambat (mm) pertumbuhan bakteri patogen, menentukan konsentrasi hambat minimum (KHM) dan konsentrasi bunuh minimum (KBM) secara in vitro, serta menentukan persentase aktivitas antibakteri ekstrak metanol batang bidara laut secara in vivo. Percobaan dilakukan menggunakan 4 kelompok konsentrasi ekstrak metanol batang bidara laut pada penelitian in vitro yaitu 25, 50, 75, dan 100% dengan ciprofloxacin sebagai kontrol positif serta aquadest sebagai kontrol negatif. Pada penelitian in vivo percobaan dilakukan menggunakan 6 kelompok perlakuan hewan uji mencit jantan galur Balb/c (Mus musculus). Hasil uji in vitro menunjukkan ekstrak metanol batang bidara laut mampu menghambat pertumbuhan bakteri patogen dengan kategori sedang terhadap Staphylococcus aureus isolat klinis dan kategori lemah terhadap Klebsiella pneumonia dan Escherichia coli isolat klinis. Nilai konsentrasi hambat minimum (KHM) untuk isolat bakteri S. aureus dan K. pneumoniae adalah pada konsentrasi 25% sedangkan untuk isolat E. coli pada konsentrasi 30%. Ekstrak metanol batang bidara laut tidak memiliki daya bunuh terhadap bakteri patogen yang diuji. Aktivitas antibakteri secara in vivo mampu menghambat pertumbuhan bakteri patogen S. aureus sebesar 6,60% (pada konsentrasi 25%), 8,62% (pada konsentrasi 50%), dan 17,31% (pada konsentrasi 100%), terhadap K. pneumonia sebesar 11,85% (pada konsentrasi 25%), 51,21% (pada konsentrasi 50%), dan 65,92% (pada konsentrasi 100%), terhadap E. coli sebesar 19,18% (pada konsentrasi 25%), 29,98% (pada konsentrasi 50%), dan 40,88% (pada konsentrasi 100%). Ekstrak metanol batang bidara laut terbukti memiliki aktivitas antibakteri secara in vitro dan in vivo. Kata kunci: Srychnos ligustrina, bakteri patogen, antibakteri, in vitro, in vivo

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In vitro and in vivo evaluation of antibacterial activity of Bridelia ferruginea extracts on some clinical isolates

The Journal of Phytopharmacology ◽

10.31254/phyto.2018.7407 ◽

2018 ◽

Vol 7 (4) ◽

pp. 392-398

Author(s):

B.T Yunana ◽

◽

B. B Bukar ◽

J. C Aguiyi ◽

◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antibacterial Activity ◽

Bark Extract ◽

Root Extract ◽

Root Bark ◽

Zone Of Inhibition ◽

Bridelia Ferruginea

The ethanol extracts of root, bark and leaf of Bridelia ferruginea was investigated for antibacterial activity against clinical isolate of Staphylococcus aureus and Escherichia coli. The extracts had significant antibacterial activity in vitro at concentration of 25 mg/ml, 50 mg/ml, 100 mg/ml and 200 mg/ml and in vivo at dose of 50 mg/kg and 100 mg/kg. The root extract in vitro had the highest zone of inhibition, followed by the bark extract for both Staphylococcus aureus and Escherichia coli. The concentration of 200 mg/ml had the highest zone of inhibition in vitro. The minimum inhibitory concentration (MIC) showed a decreasing inhibitory effect of the plant extracts for both Staphylococcus aureus and Escherichia coli as the concentration decreases with root having 3.125 mg/ml, bark having 6.25 mg/ml and leaf having 25 mg/ml for Staphylococcus aureus and Escherichia coli. Likewise, the minimum bactericidal concentration (MBC) showed decreasing bactericide effects with decrease concentration with root having 12.5 mg/ml, bark having 12.5 mg/ml and leaf having 25 mg/ml for Escherichia coli while root had 6.25mg/ml, bark had 12.5mg/ml and leaf had 25mg/ml for Staphylococcus aureus. The in vivo investigation showed that the root and bark extract exhibited antibacterial activity on both Staphylococcus aureus and Escherichia coli at doses of 100mg/kg and 50mg/kg; the root extract had higher activity than the bark and root/bark combined. The dose of 100 mg/kg had the highest colonies reduction for Staphylococcus aureus and Escherichia coli in vivo. Preliminary phytochemical screening of root, bark and leaves of Bridelia ferruginea revealed the presence of tannins, flavonoids, carbohydrates, cardiac glycoside (root, bark and leaves), saponins (root and bark). The presence of tannins, saponins, flavonoid, cardiac glycoside and carbohydrate in the bark and root extracts of the plant indicates that the bark and root extracts were pharmacological importance

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Evaluation du potentiel antimicrobien et de la toxicité des extraits de Jatropha multifida Linn, (Euphorbiaceae)

Journal of Applied Biosciences ◽

10.35759/jabs.151.4 ◽

2020 ◽

Vol 151 ◽

pp. 15550-15558

Author(s):

Amégninou Agban ◽

Yao Hoekou ◽

Passimna Pissang ◽

Tchadjobo Tchacondo ◽

Komlan Batawila

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antimicrobial Activity ◽

Candida Albicans ◽

Aqueous Extract ◽

E Coli ◽

Toxicological Studies ◽

Jatropha Multifida

Objectif : L’objectif de ce travail était d’évaluer in vitro l’activité antimicrobienne des extraits de feuilles et tige de Jatropha multifida sur la croissance de Candida albicans, Escherichia coli et Staphylococcus aureus, puis d’évaluer in vivo la toxicité de cette plante. Méthodologie et résultats : Les méthodes de diffusion en milieu gélosé et de microdilution en milieu liquide ont été utilisées pour évaluer l’effet antimicrobien. Une étude en subaigüe était réalisée afin d’explorer les effets toxiques de l’extrait aqueux des feuilles. Les résultats des tests antimicrobiens montrent une activité des extraits de feuilles et tige de J. multifida sur la croissance des souches utilisées avec des diamètres de zones d’inhibition allant de 8 à 25 mm et des concentrations minimales inhibitrices (CMI) variant de 0,039 mg/mL à 1,25 mg/mL à l’exception des souches de E. coli qui sont résistantes aux extraits de la tige. L’administration en subaigüe de l’extrait aqueux des feuilles de J. multifida à la dose de 600 mg/kg entraîne une perte significative de poids chez les souris. Conclusion et applications des résultats : Les extraits aqueux, éthanolique et hydroéthanolique des feuilles et tige de J. multifida possèdent d’activité antimicrobienne et pourraient être utilisés dans le traitement des Candidoses à C. albicans et des infections à S. aureus. Mais l’essai de toxicité subaigüe montre que l’extrait aqueux de la plante serait toxique. Des études toxicologiques approfondies restent donc nécessaires sur ces extraits afin de mieux élucider leur inocuité. Mots-clés : Jatropha multifida, extraits de feuilles et de tige, activités antifongique et antibactérienne, toxicité. Agban et al., J. Appl. Biosci. 2020 Evaluation du potentiel antimicrobien et de la toxicité des extraits de Jatropha multifida Linn, (Euphorbiaceae) 15551 Evaluation of antimicrobial potential and toxicity of Jatropha multifida Linn, (Euphorbiaceae) extracts ABSTRACT Objective: The objective of this study was to evaluate in vitro the antimicrobial activity of leaves and stem of Jatropha multifida extracts against Candida albicans, Escherichia coli and Staphylococcus aureus, and then to evaluate in vivo the toxicity of this plant. Methodology and Results: The agar well-diffusion and the NCCLS broth microdilution methods were used to assess the antimicrobial effect. A subacute study was carried out to explore the toxic effects of the aqueous extract of the leaves. The results of the antimicrobial tests show an activity of the extracts of leaves and stems of J. multifida on the growth of the strains used with diameters of inhibitory zones ranging from 8 to 25 mm and minimum inhibitory concentrations (MIC) varying from 0.039 mg/mL to 1.25 mg/mL exception E. coli strains which are resistant to extracts from the stem. Subacute administration of the aqueous extract of the leaves of J. multifida at a dose of 600 mg/kg leads to a significant loss of weight in the mice. Conclusion and application of findings : The aqueous, ethanolic and hydroethanolic extracts of the leaves and stem of J. multifida have antimicrobial activity and could be used in the treatment of Candidiasis and bacterial infections due respectively to C. albicans and S. aureus. But the subacute toxicity test shows that the aqueous extract of the plant would be toxic. Extensive toxicological studies therefore remain necessary on these extracts in order to better elucidate their safety. Keywords: Jatropha multifida extracts of leaves and stem, antifungal and antibacterial activities, toxicity

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Efficacy of Bacteriophages Against Staphylococcus aureus Isolates from Bovine Mastitis

Pharmaceuticals ◽

10.3390/ph13030035 ◽

2020 ◽

Vol 13 (3) ◽

pp. 35 ◽

Cited By ~ 2

Author(s):

Isabel Titze ◽

Tatiana Lehnherr ◽

Hansjörg Lehnherr ◽

Volker Krömker

Keyword(s):

Staphylococcus Aureus ◽

Host Range ◽

Bacterial Infections ◽

Plaque Assay ◽

Bovine Milk ◽

Bovine Mastitis ◽

Raw Milk ◽

Pasteurized Milk

The lytic efficacy of bacteriophages against Staphylococcus aureus isolates from bovine milk was investigated in vitro, regarding possible applications in the therapy of udder inflammation caused by bacterial infections (mastitis). The host range of sequenced, lytic bacteriophages was determined against a collection of 92 Staphylococcus (S.) aureus isolates. The isolates originated from quarter foremilk samples of clinical and subclinical mastitis cases. A spot test and a subsequent plaque assay were used to determine the phage host range. According to their host range, propagation and storage properties, three phages, STA1.ST29, EB1.ST11, and EB1.ST27, were selected for preparing a bacteriophage mixture (1:1:1), which was examined for its lytic activity against S. aureus in pasteurized and raw milk. It was found that almost two thirds of the isolates could be lysed by at least one of the tested phages. The bacteriophage mixture was able to reduce the S. aureus germ density in pasteurized milk and its reduction ability was maintained in raw milk, with only a moderate decrease compared to the results in pasteurized milk. The significant reduction ability of the phage mixture in raw milk promotes further in vivo investigation.

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Screening of antimicrobial activity of essential oil and methanol extract of Satureja hortensis on foodborne bacteria and fungi

Czech Journal of Food Sciences ◽

10.17221/753-cjfs ◽

2008 ◽

Vol 25 (No. 2) ◽

pp. 81-89 ◽

Cited By ~ 43

Author(s):

A. Adiguzel ◽

H. Ozer ◽

H. Kilic ◽

B. Cetin

Keyword(s):

Antimicrobial Activity ◽

Chemical Composition ◽

Minimum Inhibitory Concentration ◽

Essential Oil ◽

Inhibitory Concentration ◽

Methanol Extract ◽

Antimicrobial Activities ◽

Satureja Hortensis ◽

Bacteria And Fungi

The present work reports the in vitro antimicrobial activities of the essential oil and methanol extract from Satureja hortensis as well as the content of its essential oil. The chemical composition of hydrodistilled essential oil of Satureja hortensis was analysed by means of GC-MS. Thirty constituents were identified. The main constituents of the oil were thymol (40.54%), γ-terpinene (18.56%), carvacrol (13.98%), and p-cymene (8.97). The essential oil of Satureja hortensis exhibited the activity against 25 bacteria, 8 fungi, and a yeast, C. albicans; exerting the Minimum Inhibitory Concentration values (MIC) ranging from 15.62 to 250 µl/ml. Similarly, methanol extract of the plant also showed antimicrobial activity.

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Antimicrobial Activity of Few Medicinal Plants against Clinically Isolated Human Cariogenic Pathogens—An In Vitro Study

ISRN Dentistry ◽

10.5402/2011/541421 ◽

2011 ◽

Vol 2011 ◽

pp. 1-6 ◽

Cited By ~ 8

Author(s):

H. Shyla Jebashree ◽

S. Jayasurya Kingsley ◽

Emmanuel S. Sathish ◽

D. Devapriya

Keyword(s):

Ethyl Acetate ◽

Inhibitory Concentration ◽

Ethyl Acetate Extract ◽

In Vitro Study ◽

Ethanol Extract ◽

Psidium Guajava ◽

Terminalia Chebula ◽

Zone Of Inhibition ◽

Mimusops Elengi

Hexane, ethyl acetate, ethanol and methanol extracts of Psidium guajava, Terminalia chebula, Mimusops elengi and Achyranthes aspera were tested against the dental caries causing bacteria Streptococcus mutans and fungus Candida albicans isolated from caries infected patients. All the four extracts of P. guajava showed activity against both S. mutans and C. albicans. Maximum zone of inhibition was observed in ethyl acetate of P. guajava. The four extracts of T. chebula and M. elengi showed antibacterial activity against S. mutans. M. elengi extracts and ethanol extract of T. chebula did not show any antifungal activity against C. albicans. Except for the hexane extract of A. aspera, the other three extracts showed activity against the tested microbes. The ethyl acetate P. guajava leaf extract showed the minimum inhibitory concentration (MIC) against S. mutans to be <0.076 mg/mL in both MHB and BHI. The P. guajava ethyl acetate extract was subjected to GC-MS.

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The Antimicrobial Activity of Pechuel-Loeschea leubnitziae Leaf Extract and its Effect on The Expression Level of Methicillin Resistant Staphylococcus Aureus and Candida albicans Virulence-Associated Genes

10.1101/2022.01.11.475881 ◽

2022 ◽

Author(s):

Mariah Ndilimeke Muhongo ◽

Mourine Kangogo ◽

Christine Bii

Keyword(s):

Staphylococcus Aureus ◽

Antimicrobial Activity ◽

Candida Albicans ◽

Leaf Extract ◽

Target Genes ◽

Methicillin Resistant Staphylococcus Aureus ◽

Methanol Extract ◽

Ethanol Extract ◽

Expression Level ◽

Methicillin Resistant

The complete halt in the synthesis of new effective antimicrobial compounds is a global concern. Pathogenic microorganisms' virulence mechanisms seem to have a significant impact on their pathogenesis. The purpose of this study was to examine the antimicrobial activity of the ethanol and methanol fractions of Pechuel-Loeschea leubnitziae leaf extract, as well as its effect on the expression level of virulence-associated genes.The extract's fractions were evaluated for antimicrobial activity against Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae (clinical), Methicillin-resistant Staphylococcus aureus, and Candida albicans ATCC 90029. The test organism's antibiogram pattern was determined. The extracts' attenuation effect on the target genes of the susceptible organisms was investigated employing relative quantification using RT-qPCR. The test organism's antibiogram pattern revealed that it was drug-resistant, intermediate, and sensitive. The extracts tested positive for antimicrobial activity against Methicillin-resistant Staphylococcus aureus and Candida albicans ATCC 90029, with zones of inhibition varying from 20.33 to 29 mm. The lowest recorded MIC value was 4.688 mg/ml, while the highest was 37.5 mg/ml. In contrast to the methanol extract, the ethanol extract had a cidal action at a lower dose. The ethanol extract's Sub-MIC (18.25 mg/ml) merely reduced the expression of the hly gene in MRSA. The MRSA virulence genes were not suppressed by the sub-MIC of methanol extract (18.25 mg/ml). Notably, the expression of als1, pbl1, and sap1 in Candida albicans ATCC 90029 was significantly attenuated when exposed to sub-MICs of ethanol extract (2,344 mg/ml) and methanol extract (9.375 mg/ml). Per the findings of this research, the leaves of P. leubnitziae could be a source of an effective antimicrobial agent in the therapy of MRSA/Candida-related disorders.

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Mechanism of Action of a Prostaglandin E2 Receptor Antagonist with antimicrobial activity against Staphylococcus aureus

10.1101/2020.01.21.914200 ◽

2020 ◽

Author(s):

Elizabeth A. Lilly ◽

Mélanie A. C. Ikeh ◽

Paul L. Fidel ◽

Mairi C. Noverr

Keyword(s):

Staphylococcus Aureus ◽

Antimicrobial Activity ◽

Receptor Antagonist ◽

Mechanism Of Action ◽

Atp Production ◽

Direct Growth ◽

Prostaglandin E2 Receptor ◽

Intra Abdominal Infection

AbstractOur laboratory recently reported that the EP4 receptor antagonist, L-161,982, had direct growth-inhibitory effects on Staphylococcus aureus in vitro and in vivo, reducing microbial burden and providing significant protection against lethality in models of S. aureus monomicrobial and polymicrobial intra-abdominal infection. This antimicrobial activity was observed with both methicillin-sensitive and methicillin-resistant S. aureus (MRSA), as well as other Gram-positive bacteria. The antimicrobial activity of L-161,982 was independent of EP4 receptor inhibitory activity. In this study, we investigated the mechanism of action (MOA) of L-161,982, which contains a sulfonamide functional group. However, results demonstrate L-161,982 does not affect folate synthesis (sulfonamide MOA), oxidative stress, or membrane permeability. Instead, our results suggest that the inhibitor works via effects on inhibition of the electron transport chain (ETC). Similar to other ETC inhibitors, L-161,982 exposure results in a small colony size variant phenotype and inhibition of pigmentation, as well as significantly reduced hemolytic activity, and ATP production. In addition, L-161,982 potentiated the antimicrobial activity of another ETC inhibitor and inhibition was partially rescued by supplementation with nutrients required for ETC auxotrophs. Taken together, these findings demonstrate that L-161,982 exerts antimicrobial activity against MRSA via inhibition the ETC, representing a new member of a potentially novel antimicrobial drug class.

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