Antibacterial Activity of Borassus flabellifer Vinegar-Graphene
Quantum Dots Against Gram-Positive and Gram-Negative Bacteria

Borassus flabellifer vinegar–graphene quantum dots (BFV-GQDs) were successfully synthesized using a pyrolysis method with Borassus flabellifer vinegar (BFV) as the precursor. All the samples were characterized using ultraviolet-visible spectrophotometry (UV-Vis), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The antibacterial activities of BFV-GQDs against strains of Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Staphylococcus aureus) were determined using the agar well diffusion method for preliminary screening, while minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined using the broth macro-dilution method. The zones of inhibition were compared with those of citric acid–graphene quantum dots (CA-GQDs). It was observed that the synthesized BFV-GQDs demonstrated excellent antibacterial activity against Staphylococcus aureus (82.3%) and good antibacterial activity against Escherichia coli (73.3%). The MIC of BFV-GQDs against E. coli was 6.25 mg/mL and S. aureus was 12.5 mg/mL, whereas the MBC of BFV-GQDs against E. coli was 12.5 mg/mL and S. aureus was 25.0 mg/mL.

Download Full-text

Chemical Composition and Antibacterial Activity of the Essential Oil of Espeletia nana

Natural Product Communications ◽

10.1177/1934578x1200700530 ◽

2012 ◽

Vol 7 (5) ◽

pp. 1934578X1200700 ◽

Cited By ~ 2

Author(s):

Alexis Peña ◽

Luis Rojas ◽

Rosa Aparicio ◽

Libia Alarcón ◽

José Gregorio Baptista ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Antibacterial Activity ◽

Chemical Composition ◽

Essential Oil ◽

Diffusion Method ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Disk Diffusion Method ◽

Gram Negative ◽

Gram Positive Bacteria

The essential oil of the leaves of Espeletia nana Cuatrec, obtained by hydrodistillation, was analyzed by GC-MS, which allowed the identification of 24 components, which made up 99.9% of the oil. The most abundant compounds were α-pinene (38.1%), β-pinene (17.2%), myrcene (15.0%), spathulenol (4.2%), bicyclogermacrene (4.0%), α-zingiberene (4.0%), and γhimachalene (3.7%). Antibacterial activity was tested against Gram-positive and Gram-negative bacteria using the agar disk diffusion method. Activity was observed only against Gram-positive bacteria. MIC values were determined for Staphylococcus aureus ATCC 25923(200 μg/mL) and Enterococcus faecalis ATCC 29212 (600 μg/mL).

Download Full-text

Evaluation of Antibacterial Activity of Three Quaternary Ammonium Disinfectants on Different Germs Isolated from the Hospital Environment

BioMed Research International ◽

10.1155/2020/6509740 ◽

2020 ◽

Vol 2020 ◽

pp. 1-6

Author(s):

Amal Ramzi ◽

Bouchra Oumokhtar ◽

Yassine Ez zoubi ◽

Touria Filali Mouatassem ◽

Moussa Benboubker ◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Antibacterial Activity ◽

Quaternary Ammonium ◽

Inhibitory Concentration ◽

Hospital Environment ◽

Gram Positive ◽

Gram Negative ◽

E Coli

Background. The microbiological risk of the hospital environment, including inert surfaces, medical devices, and equipment, represents a real problem. Objective. This study is aimed at demonstrating and assessing the antibacterial activity of three synthetic disinfectants classified as quaternary ammoniums on different bacterial strains (Gram-negative and Gram-positive like Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, Pseudomonas aeruginosa, Acinetobacter baumannii, and Staphylococcus aureus) isolated from the hospital environment. The reference strains included Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29213, and Pseudomonas aeruginosa ATCC 27853 used as negative control strains. Method. Three quaternary ammonium disinfectants were tested: DDN9® (0.5%) which contains didecylmethylpolyoxyethylammonium propionate as an active substance, spray (0.4%) containing quaternary ammonium compounds, and Phagosurf ND® (0.4%) with didecyldimethylammonium chloride. Their effect was evaluated using the disk diffusion technique and the broth dilution methods, allowing the Minimum Inhibitory Concentration (MIC) and then the Minimum Bactericidal Concentration (MBC). Result. Only the growth of Gram-positive bacteria and some strains of Gram-negative bacteria were inhibited by the three synthetic disinfectants. NDD9® demonstrated an antibacterial effect only against the Gram-positive strains (S. aureus and S. aureus ATCC 29213) with a MIC of 0.25 mg/ml. The disinfectant spray showed effect against all four strains including E. coli (9), S. aureus, E. coli ATCC 25922, and P. aeruginosa ATCC 27853 with an inhibitory concentration of 4 mg/ml, while the growth of S. aureus ATCC 29213 was inhibited at 2 mg/ml. The third disinfectant, Phagosurf ND®, inhibited only the growth of S. aureus ATCC 29213 at a MIC of 4 mg/ml. Conclusion. This study is the first here in Morocco to evaluate the bacterial activity of products intended for the control of the healthcare environment. The results obtained on the three disinfectants tested reveal an ineffectiveness against some isolated strains from the hospital environment.

Download Full-text

In-vitro analysis of potential antibacterial activity of three medicinal plants

Journal of Applied and Natural Science ◽

10.31018/jans.v8i3.990 ◽

2016 ◽

Vol 8 (3) ◽

pp. 1497-1500

Author(s):

Vandana Gupta ◽

Rakesh Kumar ◽

Deepika Chaudhary ◽

Nirmal Yadav

Keyword(s):

Staphylococcus Aureus ◽

Antibacterial Activity ◽

Bacillus Subtilis ◽

Medicinal Plants ◽

Diffusion Method ◽

Gram Negative Bacteria ◽

Zone Of Inhibition ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria

The present study was aimed to examine and compare the antibacterial activity of hot methanolic extract of medicinal plants viz. Portulaca oleracea (purslane), Syzygium cumini (L.) (jamun), Psidium guajava (L.) (guava). Antibacterial activity was carried by using agar well diffusion method, against Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis) and Gram-negative bacteria (Escherichia coli). Results indicated that all the three plant extracts possess antibacterial property against Gram-positive bacteria and no activity was found against Gram-negative bacteria. Moderate zone of inhibition against Staphylococcus aureus and Bacillus subtilis was exhibited by S. cumini (L.) (11mm and 12mm) and P. guajava (L.) (10mm and 11mm) and weak zone of inhibition was exhibited by P. oleracea (5 mm and 6mm). In conclusion, S. cumini (L.) and P. guajava (L.) possess bettercapabilities of being a good candidate in search for natural antibacterial agent against infections and diseases causing Gram-positive bacteria as compared to P. oleracea.

Download Full-text

UJI DAYA ANTIBAKTERI BAWANG PUTIH (Allium sativum L.) TERHADAP BAKTERI Staphylococcus aureus, Escherichia coli, Salmonella typhimurium DAN Pseudomonas aeruginosa DALAM MENINGKATKAN KEAMANAN PANGAN

Informatika Pertanian ◽

10.21082/ip.v24n1.2015.p53-58 ◽

2015 ◽

Vol 24 (1) ◽

pp. 53 ◽

Cited By ~ 2

Author(s):

Sri Suryatmiati Prihandani

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Antibacterial Activity ◽

Food Safety ◽

Salmonella Typhimurium ◽

Diffusion Method ◽

Gram Positive ◽

Gram Negative ◽

Garlic Powder

Garlic is widely used as a herbal medicine. In order to support the empirical use and improve its application in food safety, this study was conducted to test the antibacterial activity of garlic against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli, Salmonella typhimurium and Pseudomonas aeruginosa) bacteria. Garlic was used in the form of fine powder. Garlic powder then dissolved in sterile distilled water and squeezed to obtain garlic solution with a concentration of 50%, 25% and 12.5%. Antibacterial activity of garlic juice was tested by diffusion method using paper disc to determine diameter of bacterial growth inhibition zones. Screening results demonstrated that the chemical constituents of garlic powder were saponins, flavonoids and triterpenoids. Garlic powder has antibacterial activity to Gram-positive S. aureus and Gram-negative bacteria E. coli, S. typhimurium and P. aeruginosa. Garlic has antimicrobial potential and can be used as decontaminant against Escherichia coli to maintain quality of food safety such as meat.

Download Full-text

AKTIVITAS ANTIBAKTERI INFUSA DAUN MUDA MANGROVE Sonneratia alba KERING

MEDIA TEKNOLOGI HASIL PERIKANAN ◽

10.35800/mthp.7.2.2019.23613 ◽

2019 ◽

Vol 7 (2) ◽

pp. 52

Author(s):

Yayu Mukhmin Ibrahim ◽

Verly Dotulong ◽

Djuhria Wonggo ◽

Helen Jenny Lohoo ◽

Roike Iwan Montolalu ◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antibacterial Activity ◽

Extraction Time ◽

Gram Positive ◽

Gram Negative ◽

E Coli ◽

Sample Concentration ◽

Sonneratia Alba ◽

Escherichia Coli Bacteria

Sonneratia alba mangroves are known to have bioactive compounds such as antibacterial. The purpose of this study was to determine the antibacterial activity of extract of S. alba dried mangrove leaves on Gram positive Staphylococcus aureus and Gram negative Escherichia coli bacteria. Extraction method by infusion, extraction time is 40 and 50 minutes. The extract obtained was then evaporated by the solvent above the water bath then the extracts were made concentrations of 5 and 10%. Antibacterial testing uses the modified Kirby-Bauer method. The highest yield is found in the treatment of 50 minutes infusion extraction time which is 15.6 ± 0.2%. The highest antibacterial activity against S. aureus was found in the treatment of 50 minutes extraction time both for 5% sample concentration of 7.0 mm (medium category) and at a sample concentration of 10% at 8.0 mm (medium category). While the highest antibacterial activity against E. coli bacteria was found in the treatment of 50 minutes extraction time both at 5% sample concentration of 8.0 (medium category) mm and at 10% sample concentration of 8.3 mm (medium category). From these results it can be seen that the S. alba extract of young mangrove leaf infusion has a broad spectrum antibacterial activity because it can inhibit both Gram positive S. aureus and Gram negative E. coli bacteria.Keyword: Mangrove, Sonneratia alba, infusion, rendemen, antibacterial. Mangrove Sonneratia alba diketahui memiliki senyawa bioaktif seperti antibakteri. Tujuan dari penelitian ini untuk mengetahui aktivitas antibakteri ekstrak Infusa daun muda mangrove S. alba kering terhadap bakteri Grampositif Staphylococcus aureus dan bakteri Gram negatif Escherichia coli. Metode ekstraksi dengan cara infusa, lama waktu ekstraksi yaitu40 dan 50 menit. Ekstrak yang didapatkan kemudian dievaporasi pelarutnya diatas penangas air kemudian hasil ekstrak dibuat konsentrasi 5 dan 10%. Pengujian antibakteri menggunakan metode Kirby-Bauer yang dimodifikasi. Rendemen tertinggi terdapat pada perlakuan lama ekstraksi infusa 50 menit yaitu sebesar 15,6±0,2 %. Aktivitas antibakteri tertinggi terhadap bakteri S. aureus terdapat pada perlakuan lama ekstraksi 50 menit baik untuk konsentrasi sampel 5% sebesar 7,0 mm (kategori sedang) dan pada konsentrasi sampel 10% sebesar 8,0 mm (kategori sedang). Sedangkan aktivitas antibakteri tertinggi terhadap bakteri E. coli terdapat pada perlakuan lama ekstraksi 50 menit baik pada konsentrasi sampel 5% sebesar 8,0 mm (kategori sedang) dan pada konsentrasi sampel 10% sebesar 8,3 mm (kategori sedang). Dari hasil ini dapat dilihat bahwa ekstrak infusa daun muda mangrove S. alba mempunyai aktivitas antibakteri dengan spektrum yang luas karena dapat menghambat baik bakteri Gram positif S. aureus maupun Gram negatif E. coli.Kata kunci: Mangrove, Sonneratia alba, infusa, rendemen, antibakteri.

Download Full-text

Magnitude of Multidrug Resistance among Bacterial Isolates from Surgical Site Infections in Two National Referral Hospitals in Asmara, Eritrea

International Journal of Microbiology ◽

10.1155/2021/6690222 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Eyob Yohannes Garoy ◽

Yacob Berhane Gebreab ◽

Oliver Okoth Achila ◽

Nobiel Tecklebrhan ◽

Hermon Michael Tsegai ◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Antimicrobial Agents ◽

Surgical Site Infections ◽

Diffusion Method ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Referral Hospitals

Background. The World Health Organization has emphasized the importance of understanding the epidemiology of MDR organisms from a local standpoint. Here, we report on a spectrum of bacteria associated with surgical site infections in two referral hospitals in Eritrea and the associated antibiotic susceptibility patterns. Methods. This survey was conducted between February and May 2017. A total of 83 patients receiving treatment for various surgical conditions were included. Swabs from infected surgical sites were collected using Levine technique and processed using standard microbiological procedures. In vitro antimicrobial susceptibility testing was performed on Mueller–Hinton Agar by the Kirby-Bauer disk diffusion method following Clinical and Laboratory Standards Institute guidelines. The data were analyzed using SPSS version 20. Results. A total of 116 isolates were recovered from 83 patients. In total, 67 (58%) and 49 (42%) of the isolates were Gram-positive and Gram-negative bacteria, respectively. The most common isolates included Citrobacter spp., Klebsiella spp., Escherichia coli, Proteus spp., Pseudomonas aeruginosa, Salmonella spp., Enterobacter spp., and Acinetobacter spp. In contrast, Staphylococcus aureus, CONS, and Streptococcus viridians were the predominant Gram-positive isolates. All the Staphylococcus aureus isolates were resistant to penicillin. MRSA phenotype was observed in 70% of the isolates. Vancomycin, clindamycin, and erythromycin resistance were observed in 60%, 25%, and 25% of the isolates, respectively. Furthermore, a high proportion (91%) of the Gram-negative bacteria were resistant to ampicillin and 100% of the Pseudomonas aeruginosa and Escherichia coli isolates were resistant to >5 of the tested antibiotics. The two Acinetobacter isolates were resistant to >7 antimicrobial agents. We also noted that 4 (60%) of the Klebsiella isolates were resistant to >5 antimicrobial agents. Possible pan-drug-resistant (PDR) strains were also isolated. Conclusion. Due to the high frequency of MDR isolates reported in this study, the development and implementation of suitable infection control policies and guidelines is imperative.

Download Full-text

SINTESIS NANOKOMPOSIT ZnO-MgO DAN ANALISIS EFEKTIVITAS SEBAGAI ANTIBAKTERI

CHEMISTRY PROGRESS ◽

10.35799/cp.13.1.2020.30197 ◽

2020 ◽

Vol 13 (1) ◽

Author(s):

Jessica Rompis ◽

Henry Aritonang ◽

Julius Pontoh

Keyword(s):

Escherichia Coli ◽

Molecular Weight ◽

Staphylococcus Aureus ◽

Gram Negative Bacteria ◽

Clear Zone ◽

Gram Positive ◽

Gram Negative ◽

E Coli

Telah dilakukan penelitian mengenai sintesis nanokomposit ZnO-MgO dan analisis efektivitasnya sebagai antibakteri dengan variasi berat Mg(NO3)2 .6H2O (1% & 2%) yang diambil dari berat Zn(NO3)2.4H2O. Nanokomposit tersebut dikarakterisasi menggunakan XRD dan EDS serta diuji efektivitas antibakterinya. Uji efektivitas antibakteri mengunakan bakteri Staphylococcus aureus (Gram-positif) dan Escherichia coli (Gram-negatif). Hasil penelitian menunjukan bahwa ukuran nanopartikelnya adalah 17,41 nm, dan 16,84 nm,. Kemudian efektivitas antibakteri diketahui berdasarkan luasnya zona bening yang terbentuk dan diperoleh masing-masing sebesar 16,7 mm, dan 17,9 mm, untuk bakteri E.coli dan 15 mm, 15,8 mm, untuk bakteri S.aureus. Nanokomposit ZnO-MgO lebih efektif dalam menghambat pertumuhan bakteri E.coli dibandingkan dengan bakteri S.aureus.ABSTRACT Research on the synthesis of ZnO-MgO nanocomposites and analysis of its effectiveness as an antibacterial has been carried out with variations in molecular weight of Mg (NO3) 2.6H2O (1%, & 2%) taken from the weight of Zn (NO3) 2.4 H2O.The nanocomposites were characterized using XRD and EDS and tested for their antibacterial effectiveness.Antibacterial effectiveness test using Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) bacteria. The results showed that the size of the nanoparticles were 17.41 nm, and 16.84 nm,. Then the effectiveness of antibacterial is known based on the extent of the clear zone formed and obtained respectively of 16.7 mm, and 17.9 mm, for bacteria E. coli and 15 mm, and 15.8 mm for S.aureus bacteria.

Download Full-text

Bioactive compounds isolated from submerged fermentations of the Chilean fungus Stereum rameale

Zeitschrift für Naturforschung C ◽

10.1515/znc-2015-5005 ◽

2015 ◽

Vol 70 (3-4) ◽

pp. 97-102 ◽

Cited By ~ 7

Author(s):

Pedro Aqueveque ◽

Carlos Leonardo Céspedes ◽

José Becerra ◽

Marcelo Dávila ◽

Olov Sterner

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Antibacterial Activity ◽

Bioactive Metabolites ◽

Gram Negative Bacteria ◽

Gram Negative ◽

E Coli ◽

Gram Positive Bacteria ◽

Bioassay Guided Fractionation

Abstract Liquid fermentations of the fungus Stereum rameale (N° 2511) yielded extracts with antibacterial activity. The antibacterial activity reached its peak after 216 h of stirring. Bioassay-guided fractionation methods were employed for the isolation of the bioactive metabolites. Three known compounds were identified: MS-3 (1), vibralactone (2) and vibralactone B (3). The three compounds showed antibacterial activity as a function of their concentration. Minimal bactericidal concentrations (MBC) of compound 1 against Gram-positive bacteria were as follows: Bacillus cereus (50 μg/mL), Bacillus subtilis (10 μg/mL) and Staphylococcus aureus (100 μg/mL). Compounds 2 and 3 were active only against Gram-negative bacteria. The MBC of compound 2 against Escherichia coli was 200 μg/mL. Compound 3 inhibited significantly the growth of E. coli and Pseudomonas aeruginosa, with MBC values of 50 and 100 μg/mL, respectively.

Download Full-text

In-vitro Antioxidant and Antibacterial Activity of Methanolic Extract of Shorea robusta Gaertn. F. Resin

International Journal of Pharmaceutical and Phytopharmacological Research ◽

10.24896/eijppr.2016641 ◽

2016 ◽

Vol 6 (4) ◽

pp. 68

Author(s):

Sushma Vashisht ◽

Manish Pal Singh ◽

Viney Chawla

Keyword(s):

Antibacterial Activity ◽

Methanolic Extract ◽

Diffusion Method ◽

Gram Negative Bacteria ◽

Disc Diffusion ◽

Gram Positive ◽

Gram Negative ◽

Shorea Robusta ◽

Dose Dependent ◽

Resin Extract

The methanolic extract of the resin of Shorea robusta was subjected to investigate its antioxidant and antibacterial properties its utility in free radical mediated diseases including diabetic, cardiovascular, cancer etc. The methanol extract of the resin was tested for antioxidant activity using scavenging activity of DPPH (1,1-diphenyl-2-picrylhydrazil) radical method, reducing power by FeCl3 and antibacterial activity against gram positive and gram negative bacteria using disc diffusion method. The phytochemical screening considered the presence of triterpenoids, tannins and flavoniods. Overall, the plant extract is a source of natural antioxidants which might be helpful in preventing the progress of various oxidative stress mediated diseases including aging. The half inhibition concentration (IC50) of resin extract of Shorea robusta and ascorbic acid were 35.60 µg/ml and 31.91 µg/ml respectively. The resin extract exhibit a significant dose dependent inhibition of DPPH activity. Antibacterial activity was observed against gram positive and gram negative bacteria in dose dependent manner.Key Words: Shorea robusta, antioxidant, antibacterial, Disc-diffusion, DPPH.

Download Full-text

Antibacterial activity of magnesium oxide nanoparticles prepared by Calcination method

International Journal of Pharmaceutical Quality Assurance ◽

10.25258/ijpqa.10.3.25 ◽

2019 ◽

Vol 10 (03) ◽

Author(s):

Elaf Ayad Kadhem ◽

Miaad Hamzah Zghair ◽

Sarah , Hussam H. Tizkam, Shoeb Alahmad Salih Mahdi ◽

Hussam H. Tizkam ◽

Shoeb Alahmad

Keyword(s):

Antibacterial Activity ◽

Magnesium Oxide ◽

Diffusion Method ◽

Oxide Nanoparticles ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Magnesium Oxide Nanoparticles ◽

Agar Disc

magnesium oxide nanoparticles (MgO NPs) were prepared by simple wet chemical method using different calcination temperatures. The prepared NPs were characterized by Electrostatic Discharge (ESD), Scanning Electron Microscope (SEM) and X-ray Diffraction (XRD). It demonstrates sharp intensive peak with the increase of crystallinty and increase of the size with varying morphologies with respect to increase of calcination temperature. Antibacterial studies were done on gram negative bacteria (E.coli) and gram positive bacteria (S.aureus) by agar disc diffusion method. The zones of inhibitions were found larger for gram positive bacteria than gram negative bacteria, this mean, antibacterial MgO NPs activity more active on gram positive bacteria than gram negative bacteria because of the structural differences. It was found that antibacterial activity of MgO NPs was found it has directly proportional with their concentration.

Download Full-text