scholarly journals Antibacterial Activity ofMulinum spinosumExtracts against Slime-ProducingStaphylococcus aureusand Methicillin-ResistantStaphylococcus aureusIsolated from Nasal Carriers

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Echenique Daniela ◽  
Chiaramello Alejandra ◽  
Rossomando Pedro ◽  
Mattana Claudia ◽  
Alcaráz Lucía ◽  
...  

Nasal carriers ofStaphylococcus aureusare important reservoirs with risk of developing endogenous infections or transmitting infections to susceptible individuals. Methicillin-resistantS. aureus(MRSA) are associated with higher rates of treatment failure. Some strains ofS. aureusproduce slime which is believed to make the microorganisms more resistant to antibiotics and host defenses. The antibacterial activity of ethyl acetate : n-hexane (EtOAc : HEX) extracts ofMulinum spinosum(5 : 95% EtOAc : HEX, 50 : 50% EtOAc : HEX, 70 : 30% EtOAc : HEX and mix 20 : 80/30 : 70% EtOAc : HEX, 50 : 50/70 : 30/100 : 0% EtOAc : HEX) were assayed against 3 slime-producingS. aureusstrains and 2 MRSA strains isolated from nasal carriers.S. aureusATCC 35556 slime-producing strain and MRSA ATCC 43300 strain were used as controls. The extracts were prepared using flash chromatography.M. spinosum5 : 95% AcOEt : HEX showed antibacterial effect against all slime-producing strains (MIC: 500 µg/mL) and the highest activity against MRSA strains (MIC: 500 to 1000 µg/mL). AllM. spinosumextracts assayed were active against slime-producingS. aureusand MRSA at doses between 500 and 4000 µg/mL. Both, slime-producingS. aureusand MRSA are highly contagious and hardly eradicated by antibiotic therapies. So, there is an increasing need to find new substances with the ability to inhibit these strains.

Author(s):  
Triveni A G ◽  
Suresh Kumar Mendem ◽  
Channapa T Shivannavar ◽  
Subhaschandra M Gaddad

 Objective:The continuous rise in the prevalence of multi drug resistance pathogens globally is threatening the treatment and management of infectious diseases. Ethno medicine plays a key role in the exploration for novel bioactive compounds. The present study evaluates the antibacterial and antibiofilm activities of the crude extracts of Lawsonia inermis against clinical isolates of methicillin resistant Staphylococcus aureus (MRSA).Materials and methods: Shade dried and finely powdered leaves of the plant were extracted by maceration method using six solvents methanol, acetone, ethyl acetate, chloroform, petroleum ether and n-hexane. Antibacterial and antibiofilm activities of the extracts against MDR MRSA by agar cup diffusion and tube method respectively.Results: Methanol extract showed the highest antibacterial activity of 18mm compared to other extracts. Similarly, petroleum ether extract showed highest biofilm inhibition of 84.7%. Other solvent extracts also exhibited significant biofilm inhibition [n-Hexane-83.6%, Ethyl acetate -79.5%, Chloroform-79.2%, Acetone -77% and Methanol-77%].Conclusion: The leaf extracts of L. inermis have shown promising biofilm inhibitory activity and good antibacterial activity, which can be explored for the development of new drugs for the MDR pathogens. Keywords: Antibioticacivity, Antibiofilm activity, L.inermis, MRSA


Scientifica ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Hasanga Rathnayake ◽  
Manikkuwadura Hasara Nethmini De Zoysa ◽  
Ruwani Punyakanthi Hewawasam ◽  
Weerasinghe Mudiyanselage Dilip Gaya Bandara Wijayaratne

Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of hospital- and community-acquired infections worldwide. Therefore, this study was conducted to explore the antibacterial activity of the two medicinal plants Epaltes divaricata and Vetiveria zizanioides against strains of MRSA which were isolated from patients with skin and soft tissue infections. Hexane, ethanol, and water extracts of E. divaricata (whole plant) and V. zizanioides (roots) were prepared. Clinical isolates of MRSA strains (n = 20) were used for the study. Bacterial susceptibility was tested using a disc diffusion assay. Minimum inhibitory concentration (MIC) was determined by a broth microdilution method. Vancomycin was used as the positive control. Hexane, ethanol, and water extracts of E. divaricata showed inhibitory zones against MRSA. Except for water extract, both hexane and ethanol extracts of V. zizanioides showed inhibitory zones. MIC ranges of hexane, ethanol, and water extracts in E. divaricata were 0.012–0.32 mg/mL, 0.019–2.4 mg/mL, and 0.019–0.48 mg/mL, respectively. Respective MIC ranges of hexane and ethanol extracts of V. zizanioides were 0.003–0.032 mg/mL and 0.019–2.4 mg/mL. The hexane extract of V. zizanioides inhibited 55% of the selected MRSA strains at a relatively low MIC value of 0.012 mg/mL. The hexane extract of both plants demonstrated inhibition of 75% of MRSA strains at a MIC value of 0.064 mg/mL. Ethanol extract of V. zizanioides and E. divaricata, respectively, inhibited 70% and 45% of MRSA strains at the MIC of 0.096 mg/mL, whereas water extract of E. divaricata inhibited 80% of MRSA strains at the same MIC. Both E. divaricata and V. zizanioides were equally effective against MRSA at a MIC of 0.064 mg/mL. But V. zizanioides was more effective since the hexane extract inhibited more than 50% of MRSA strains at significantly a lower MIC value of 0.012 mg/mL. Fractionation, purification, and identification of active compounds will warrant further evaluation of the therapeutic potential of both plant extracts.


2009 ◽  
Vol 11 (4) ◽  
pp. 90 ◽  
Author(s):  
Guo Ying Zuo ◽  
Fan Yan Meng ◽  
Xiao Yan Hao ◽  
Yun Ling Zhang ◽  
Gen Chun Wang ◽  
...  

Purpose. This study describes the antibacterial effect of extracts and compounds isolated from the aerial part of Chelidonium majus Linn. (Papaveraceae) acting against clinical strains of methicillin-resistant Staphylococcus aureus (MRSA). Methods. The activities were evaluated by using the macrobroth dilution method and reported as the MICs/MBCs. Results. Bioassay-guided fractionation of the most active extract from the aerial parts (EtOAc) led to the isolation of benzo[c]phenanthridine-type alkaloids 8-hydroxydihydrosanguinarine (hhS), 8-hydroxydihydrochelerythrine (hhC), which were potently active against MRSA strains. Conclusions. The selective antibacterial activity reported in this paper for 8-hydroxylated benzo[c]phenanthridine-type alkaloids isolated from C.majus opens the possibility that they could be helpful for the developing of new antibacterial agents for treating the infection of MRSA which has created nosocomial problem worldwide.


PLoS ONE ◽  
2021 ◽  
Vol 16 (10) ◽  
pp. e0258607
Author(s):  
Shivankar Agrawal ◽  
Jusna Nandeibam ◽  
Indira Sarangthem

Staphylococcus aureus and Methicillin-resistant S. aureus (MRSA) remains one of the major concerns of healthcare associated and community-onset infections worldwide. The number of cases of treatment failure for infections associated with resistant bacteria is on the rise, due to the decreasing efficacy of current antibiotics. Notably, Acrophialophora levis, a thermophilous fungus species, showed antibacterial activity, namely against S. aureus and clinical MRSA strains. The ethyl acetate extract of culture filtrate was found to display significant activity against S. aureus and MRSA with a minimum inhibitory concentration (MIC) of 1 μg/mL and 4 μg/mL, respectively. Scanning electron micrographs demonstrated drastic changes in the cellular architecture of metabolite treated cells of S. aureus and an MRSA clinical isolate. Cell wall disruption, membrane lysis and probable leakage of cytoplasmic are hallmarks of the antibacterial effect of fungal metabolites against MRSA. The ethyl acetate extract also showed strong antioxidant activity using two different complementary free radicals scavenging methods, DPPH and ABTS with efficiency of 55% and 47% at 1 mg/mL, respectively. The total phenolic and flavonoid content was found to be 50 mg/GAE and 20 mg/CAE, respectively. More than ten metabolites from different classes were identified: phenolic acids, phenylpropanoids, sesquiterpenes, tannins, lignans and flavonoids. In conclusion, the significant antibacterial activity renders this fungal strain as a bioresource for natural compounds an interesting alternative against resistant bacteria.


Author(s):  
ZAMHARIRA MUSLIM ◽  
YONANIKO DEPHINTO

Objective: This research aims to analyze the ability of robusta coffee leaves fraction extract to inhibit the growth of Staphylococcus aureus and Escherichia coli and also determine the minimum inhibitory concentration (MIC). Methods: Antibacterial activity evaluated by the disc diffusion method observed in four types of fraction of extract robusta coffee leaves (n-hexane, ethyl acetate, ethanol, and water). Each extract divided into three various concentrations, 5%, 10%, and 15%. Determination of antimicrobial activity in vitro by the disk diffusion method. Results: Ethyl acetate fraction of coffee leaves extract produced the largest diameter zone of inhibition of bacterial growth compared to other extraction fractions of 17.28 mm in E. coli and 18.58 mm in S. aureus. The MIC of coffee leaves extract fraction water, ethyl acetate, and n-hexane on E. coli and S. aureus is 5%, while the fraction ethanol MIC is 10%. Conclusion: The antibacterial effect of ethyl acetate fraction of coffee leaves extract showed an antibacterial effect that was better than the fraction of n-hexane, ethanol, and water.


2015 ◽  
Vol 10 (3) ◽  
pp. 1934578X1501000 ◽  
Author(s):  
Hitoshi Tanaka ◽  
Ikunori Atsumi ◽  
Motori Hasegawa ◽  
Miyuki Hirata ◽  
Tatsuko Sakai ◽  
...  

Two new isoflavanones, eryvarins Y (1) and Z (2), together with three known compounds (3–5) were isolated from the roots of Erythrina variegata. The structures of 1 and 2 were established on the basis of spectroscopic data. The new compounds are peculiar isoflavanones, possessing both a 3-methylbut-2-en-1-yl group and a 2-hydroxy-3-methylbut-3-en-1-yl group. Among the isolates, orientanol E (5) exhibited potent antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) strains.


2012 ◽  
Vol 57 (1) ◽  
pp. 205-211 ◽  
Author(s):  
Adam Belley ◽  
Francis F. Arhin ◽  
Ingrid Sarmiento ◽  
Hong Deng ◽  
Warren Rose ◽  
...  

ABSTRACTThe safety and efficacy of a single 1,200-mg dose of the lipoglycopeptide oritavancin are currently being investigated in two global phase 3 studies of acute bacterial skin and skin structure infections. In this study, anin vitropharmacokinetic/pharmacodynamic model was established to compare the free-drug pharmacodynamics associated with a single 1,200-mg dose of oritavancin to once-daily dosing with daptomycin at 6 mg/kg of body weight and twice-daily dosing with vancomycin at 1,000 mg against three methicillin-resistantStaphylococcus aureus(MRSA) strains over 72 h. The area under the bacterial-kill curve (AUBKC) was used to assess the antibacterial effect of each dosing regimen at 24 h (AUBKC0-24), 48 h (AUBKC0-48), and 72 h (AUBKC0-72). The rapid bactericidal activities of oritavancin and daptomycin contributed to lower AUBKC0-24s for the three MRSA strains than with vancomycin (P< 0.05, as determined by analysis of variance [ANOVA]). Oritavancin exposure also resulted in a lower AUBKC0-48and AUBKC0-72against one MRSA strain and a lower AUBKC0-48for another strain than did vancomycin exposure (P< 0.05). Furthermore, daptomycin exposure resulted in a lower AUBKC0-48and AUBKC0-72for one of the MRSA isolates than did vancomycin exposure (P< 0.05). Lower AUBKC0-24s for two of the MRSA strains (P< 0.05) were obtained with oritavancin exposure than with daptomycin. Thus, the antibacterial effect from the single-dose regimen of oritavancin is as effective as that from either once-daily dosing with daptomycin or twice-daily dosing with vancomycin against the MRSA isolates tested in anin vitropharmacokinetic/pharmacodynamic model over 72 h. These results provide further justification to assess the single 1,200-mg dose of oritavancin for treatment of acute bacterial skin and skin structure infections.


2011 ◽  
Vol 233-235 ◽  
pp. 2328-2331 ◽  
Author(s):  
Hui Juan Wang ◽  
Hao Chen ◽  
Guang Ting Han

In this study, the total flavone contents of Apocynum venetum extract and Apocynum venetum fiber extracts were evaluated. Their antibacterial activity was tested via testing the antibacterial effect of their aqueous, ethyl acetate and n-butyl alcohol extracts. The results were showed that both the materials extracts at the concentration of 100, 50mg/ml had significantly antibacterial activities against staphylococcus aureus, and had a few effect on bacillus subtilis, pseudomonadaceae, pseudomonas aeruginosa, staphylococcus epidermidis, escherichia coli and candida albicans.


Plants ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 1539
Author(s):  
Nawal Buzgaia ◽  
Tahani Awin ◽  
Fakhri Elabbar ◽  
Khaled Abdusalam ◽  
Soo Yee Lee ◽  
...  

Arbutus pavarii Pamp is a medicinal plant commonly used by local tribes in East Libya for the treatment of many diseases, such as gastritis, renal infections, cancer and kidney diseases. In this study, the antibacterial activity of the leaf and stem bark extracts of the plant against methicillin-resistant Staphylococcus aureus (MRSA), as well as the metabolite profiles of the bioactive fractions, was investigated. The antibacterial activity was determined by disc diffusion method, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), while the microbial reduction by the bioactive fraction was evaluated using time–kill test. The bioactive fraction was further subjected to ultrahigh-performance liquid chromatography–mass spectrometry (UHPLC-ESI-MS/MS) analysis to putatively identify the chemical constituents contained therein. All the extracts and fractions showed different levels of antibacterial activity on the tested MRSA strains. The highest total antibacterial activity, i.e., 4007.6 mL/g, was exhibited by the crude leaf methanolic extract. However, the ethyl acetate fraction of the leaf showed moderate to significant antibacterial activity against MRSA at low MIC (0.08–1.25 mg/mL). Metabolite profiling of this fraction using UHPLC-ESI-MS/MS resulted in the putative identification of 28 compounds, which included phenolic acids, flavan-3-ols and flavonols. The results of this study showed that the ethyl acetate fraction of Arbutus pavarii leaf possessed potential antibacterial activity against MRSA and hence can be further explored for pharmaceutical applications as a natural antibacterial agent.


Sign in / Sign up

Export Citation Format

Share Document