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Author(s):  
Sri Hidanah ◽  
Emy Koestanti Sabdoningrum ◽  
Soeharsono . ◽  
Ayu Andira ◽  
Noor Amina Varhana

Background: Salmonella Pullorum are pathogenic bacteria that causes salmonellosis and causes heavy economic losses in the poultry industry and are zoonotic. Treatment of diseases caused by bacteria generally use antibiotics, but excessive administration of antibiotics causes bacterial resistance and residues in livestock. Major chemical constituents of Sambiloto are andrographolide and flavonoids. Andrographolide has antibacterial effect in addition to being antitoxic, anticancer, anti-inflammatory and antiallergic. Methods: The research was conducted by isolating and identifying Salmonella Pullorum on SSA media and a series of biochemical tests (TSIA, SIM, SCA, urea media and sugar test), manufacturing sambiloto extract, testing the sensitivity of several antibiotics using the disk diffusion method and testing the activation of sambiloto extract against Salmonella Pullorum using the disk diffusion and dilution methods. Result: The result show that sambiloto had antibacterial activity because it contained andrographolide, flavonoids, saponins, alkaloids and tannins and the lowest extract dose that effectively killed Salmonella Pullorum is concentrations of 20%.


Nova ◽  
2021 ◽  
Vol 19 (37) ◽  
pp. 121-134
Author(s):  
Lidia Po Catalao Dionisio ◽  
Alejandro Manuel Labella ◽  
María Palma ◽  
Juan José Borrego

Aim. In vitro antimicrobial activities of seven wines (5 reds and 2 whites) from the Douro region (Iberian Peninsule) against eleven clinical strains of Helicobacter pylori were evaluated. Methods. The disk diffusion method, using Columbia Agar supplemented with horse blood (CAB), were used to determine the antimicrobial properties of some wine components against H. pylori strains. Potential interactions of antioxidants contained in the wines and two antimicrobials (amoxicillin and metronidazole) were studied by the disk diffusion method. Results. All the tested strains showed growth in CAB supplemented with 9% of the tested wines but none of them grew in media supplemented with 45% and 67.5% of wine. Similarly, all the tested strains grew in media with the concentration of proanthocyanidins present in the different types of the studied wines. The Minimal Inhibitory Concentration (MIC) values of the wine antioxidant components tested (benzoic acid, catechin, quercetin, and resveratrol) indicate that resveratrol was the most powerful inhibitory substance against H. pylori. An effect of potentiation between amoxicillin and metronidazole and the antioxidants tested was also established. The interaction of amoxicillin and resveratrol or metronidazole and catechin increased the antimicrobial activity against H. pylori. Conclusions. The results obtained suggested a potential role of resveratrol as a chemopreventive agent for H. pylori infection.


Antibiotics ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 4
Author(s):  
Vinicius de Queiroz Albuquerque ◽  
Maria Janeila Carvalho Soares ◽  
Maria Nágila Carneiro Matos ◽  
Rafaela Mesquita Bastos Cavalcante ◽  
Jesús Alberto Pérez Guerrero ◽  
...  

The aim of this study was to evaluate the phytochemical profile of Cinnamomum zeylanicum essential oil (CZEO) and their antimicrobial and antibiofilm activity against Staphylococcus strains isolated from canine otitis. First, the CZEO chemical composition was determined by gas chromatography-mass spectrometry (CG-MS). External otitis samples collected from dogs were submitted to staphylococcal isolation, followed by MALDI-TOF mass spectrometry identification. The antimicrobial action was tested against the isolates using the disk-diffusion and microdilution methods. The antibiofilm activity was evaluated by CZEO-based concentrations, subMIC for biofilm formation and supraMIC against preformed biofilm, quantified by crystal violet (CV) staining and CFU counting. The chemical analysis revealed that (E)-cinnamaldehyde, eugenol and (E)-cinnamyl acetate were the main compounds in the CZEO, representing 77.42, 8.17 and 4.50%, respectively. Two strains of three different species, S. saprophyticus, S. schleiferi and S. pseudintermedius, were identified. The disk-diffusion test showed an inhibitory zone diameter, ranging from 34.0 to 49.5 mm, while the MIC and MBC values were around 500 and 1000 µg/mL. SubMIC demonstrated an inhibition on biofilm formation against 4 out the 6 strains tested. On mature biofilm, the CZEO-based supraMIC groups had slightly change on biomass, however, the biofilm cell viability decreased the CFU in 3 magnitude orders.


2021 ◽  
Vol 9 (3) ◽  
pp. 179-186
Author(s):  
Devi Yanti Sari ◽  
Herwin Pisestyani ◽  
Denny Widaya Lukman

Kebab merupakan salah satu makanan siap saji atau ready to eat (RTE) yang populer di seluruh dunia. Escherichia coli (E. coli) O157:H7 banyak dihubungkan dengan kejadian outbreak foodborne disease pada kebab. Kontaminasi E. coli O157:H7 resistan antibiotik pada kebab dapat menimbulkan masalah kesehatan serius. Penelitian ini bertujuan mengidentifikasi E. coli O157:H7 resistan antibiotik yang diisolasi dari daging kebab yang dijual di sekitar Kampus IPB Dramaga Bogor. Total 43 sampel daging kebab diambil dari seluruh pedagang kebab di sekitar Kampus IPB Dramaga dalam radius 2 km dari batas terluar Kampus. Isolasi dan identifikasi E. coli mengacu pada Standar Nasional Indonesia (SNI) 2897:2008 dari Badan Standardisasi Nasional tentang Metode Pengujian Cemaran Mikroba dalam Daging, Telur, dan Susu, serta Hasil Olahannya. Uji serotyping E. coli O157:H7 menggunakan uji Serologis. Uji resistansi E. coli O157:H7 mengacu pada standar Clinical Laboratory Standards Institute (CLSI) dan dilakukan terhadap 10 jenis antibiotik menggunakan metode Kirby-Bauer disk diffusion. Data yang diperoleh dianalisis secara deskriptif. Hasil penelitian menunjukkan enam isolat positif E. coli O157:H7 (31.6%; 6/19) yang resistan terhadap ampisilin, amoksisilin-asam klavulanat, sefotaksim, gentamisin, siprofloksasin, enrofloksasin, kolistin sulfat dengan satu isolat termasuk multidrug resistant (MDR). Semua isolat E. coli O157:H7 masih sensitif terhadap trimethoprim-sulfametoksasol, oksitetrasiklin, dan kloramfenikol.


2021 ◽  
Vol 10 (48) ◽  
Author(s):  
Marissa N. Schroeter ◽  
Safiya J. Gazali ◽  
Anutthaman Parthasarathy ◽  
Crista B. Wadsworth ◽  
Renata Rezende Miranda ◽  
...  

We report the isolation, whole-genome sequencing, and annotation of Enterobacter sp. strain RIT 637, Pseudomonas sp. strain RIT 778, and Deinococcus sp. strain RIT 780. Disk diffusion assays using spent medium demonstrated that all bacteria produced bactericidal compounds against Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, and Staphylococcus aureus ATCC 25923.


2021 ◽  
Vol 14 (11) ◽  
Author(s):  
Farzad Mohamadi ◽  
Jalil Vand Yousefi ◽  
Naser Harzandi ◽  
Sobhan Ghafourian

Background: Due to the importance of identifying the source of infectious agents, different typing methods have been developed, among which the pulsed-field gel electrophoresis (PFGE) method is known as the gold standard for bacteria. Also, Enterococcus faecalis is classified as a nosocomial infection. Objectives: The current study aimed to identify the source of E. faecalis by the PFGE method. Methods: Bacteria were collected from all cases of urinary tract infections. Then, the identification process was performed. All isolates were evaluated for vancomycin resistance, and then PFGE was carried out. Results: The results of disk diffusion showed that 54% of the isolates showed resistance to vancomycin. Also, 4% of the isolates were intermediate, and 42% showed sensitivity to vancomycin. Afterwards, the PCR of the VanA gene was performed to confirm the results of disk diffusion. Thus, 48 out of 54 (88.8%) isolates had the VanA gene, and none of the four intermediate isolates had the VanA gene. Our results demonstrated that 54 isolates were vancomycin-resistant, and 50 different pulsotypes groups were identified. Conclusions: Our findings showed the isolates of E. faecalis were from different clonal lineages.


2021 ◽  
Author(s):  
Emma Mills ◽  
Erin Sullivan ◽  
Jasna Kovac

A collection of 85 Bacillus cereus group isolates were screened for phenotypic resistance to nine antibiotics using disk diffusion and broth microdilution. The broth microdilution antimicrobial results were interpreted using the CLSI M45 breakpoints for Bacillus spp. Due to the lack of Bacillus spp. disk diffusion breakpoints, the results obtained with the disk diffusion assay were interpreted using the CLSI M100 breakpoints for Staphylococcus spp. We identified significant (p < 0.05) discrepancies in resistance interpretation between the two methods for ampicillin, gentamicin, rifampicin, tetracycline, and trimethoprim/sulfamethoxazole. Antimicrobial resistance genes were detected using unassembled and assembled whole-genome sequences with Ariba and Abricate, respectively, to assess the sensitivity and specificity for predicting phenotypic resistance based on the presence of antimicrobial resistance genes. We found antimicrobial resistance gene presence to be a poor indicator for phenotypic resistance, calling for further investigation of mechanisms underlying antimicrobial resistance in the B. cereusgroup. Genes with poor sensitivity and/or specificity, as determined based on broth microdilution results included rph(rifampicin, 0%, 95%), mphgenes (erythromycin, 0%, 96%), and all vangenes (vancomycin, 100%, 35%). However, Bc(ampicillin, 64%, 100%) andtet genes (tetracycline, 67%, 100%) were highly specific, albeit moderately sensitive indicators of phenotypic resistance based on broth microdilution results. Only beta-lactam resistance genes (Bc, BcII, and blaTEM) were highly sensitive (94%) and specific (100%) markers of resistance to ceftriaxone based on the disk diffusion results, providing further evidence of these beta-lactams' role in nonsusceptibility of Bacillus cereus group isolates to ceftriaxone.


2021 ◽  
pp. 2929-2935
Author(s):  
Kealeboga Mileng ◽  
Tsepo A. Ramatla ◽  
Rendani V. Ndou ◽  
Oriel M. M. Thekisoe ◽  
Michelo Syakalima

Background and Aim: Infections with Campylobacter species have gained recognition as the most frequent cause of foodborne gastroenteritis globally. Their significance in South Africa is still an area of study interest. This study was, therefore, carried out to determine the occurrence of Campylobacter species in chickens from North West Province of South Africa as well as their antibiotic sensitivity status. Materials and Methods: A total of 2400 chicken fecal samples were collected and pooled to a total of 480 samples from five registered active poultry abattoirs in the Ngaka Modiri Molema District of North West Province, South Africa. Polymerase chain reaction (PCR) was used for the detection of Campylobacter spp. targeting the 16S rRNA gene while antibiotic sensitivity was determined using disk diffusion inhibition test. Results: After isolation, a total of 26 samples were confirmed to be harboring Campylobacter jejuni by PCR and sequencing. C. jejuni was found to be the only isolate detected in all the fecal samples tested. The study further demonstrated that C. jejuni infections were highest in the summer season (3%) followed by autumn and winter at 1%, while there were none detected in the spring. The isolated C. jejuni-positive samples on disk diffusion inhibition test displayed resistance to nalidixic acid, tetracycline, erythromycin, and ciprofloxacin at 98%, 80%, 83%, and 21%, respectively. Conclusion: C. jejuni isolated in this study is known to cause disease in humans, and thus its occurrence requires application of "One Health" strategy to reduce the spread of this zoonotic pathogen in South Africa.


2021 ◽  
Vol 8 (03) ◽  
pp. e143-e152
Author(s):  
Antonia Carolina Melo Monteiro ◽  
Aminata Doucoure Drame ◽  
Francisca Melo Nascimento ◽  
Ana Luisa Miranda-Vilela ◽  
Alexandre Vasconcelos Lima ◽  
...  

Abstract Aspergillus fumigatus is the main etiological agent of aspergillosis. Considering azole antifungal drug resistance in A. fumigatus, which compromises treatment, new alternatives are needed. Among them, essential oils (EOs) can be an alternative treatment, having shown positive results in inhibiting phytopathogenic fungi in vitro. We aimed to determine the in vitro antifungal activity of Origanum vulgare L. subsp. hirtum (Link) (oregano) and Rosmarinus officinalis L. (rosemary) EOs alone and in association (O. vulgare+R. officinalis) against A. fumigatus. EOs were analyzed by gas chromatography (GC-FID and GC/MS systems), and analyses showed that the major components of O. vulgare EO were carvacrol (67.8%), p-cymene (14.8%), and thymol (3.9%); for R. officinalis, they were the monoterpenes 1,8-cineole (49.1%), camphor (18.1%) and α-pinene (8.1). For biological assays, five EO concentrations, 0.2; 0.4; 0.6; 0.8 and 1.0%, were used in disk diffusion and agar dilution tests for 21 days. In disk diffusion, O. vulgare EO alone and in association (O. vulgare+R. officinalis) showed fungicidal activity at all concentrations. In agar dilution, inhibitory action was demonstrated from 0.6% for O. vulgare EO and in association (O. vulgare+R. officinalis). R. officinalis EO at 1.0% showed no fungal growth, determining the minimum inhibitory concentration (MIC). The present study demonstrated inhibitory actions of O. vulgare and R. officinalis EOs in A. fumigatus. GC analyses corroborated the literature regarding their antibacterial and antifungal effects. However, further in vitro and in vivo studies are needed to evaluate EOs as alternative antifungals for treating aspergillosis.


2021 ◽  
Vol 2021 ◽  
pp. 1-5
Author(s):  
Ândrea Celestino de Souza ◽  
Luciano Z. Goldani ◽  
Eliane Würdig Roesch ◽  
Larissa Lutz ◽  
Patricia Orlandi Barth ◽  
...  

Determination of the susceptibility profile of isolates of Candida from blood culture bottles is extremely important for correctly guiding patient pharmacotherapy. The aim of this study was to compare the results of analysis of Candida isolated directly from blood culture bottles by the VITEK MS MALDI-TOF identification system and the fluconazole disk diffusion assay with those of standard identification methods. Testing directly from the bottle allowed results 24 to 48 hours quicker than the standard method. There was a categorical agreement of 51.64% (47 of 91 samples) between the results of analysis directly from the bottle and analysis by the standard method. Regarding species identification, there was 96.15% agreement for Candida parapsilosis (25 of 26 samples). Categorical agreement between the rapid and standard disk diffusion methods was 95%, and the agreement between the rapid disk diffusion method and the broth microdilution method was 97%. Only minor errors in the rapid method were observed: 3 (5%) in the standard disk diffusion method and 2 (3%) in the broth microdilution method. Our study concluded that the rapid disk diffusion method for fluconazole is a fast, easy, reproducible, and consistent method. Its timely implementation for testing antifungal agents in the clinical microbiology laboratory can help reduce profile release times, thus helping to determine the most appropriate antifungal treatment.


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