Phytochemicals and Antimicrobial Evaluation of Tapinathus bangwensis Leaves

Background: The leaves of Tapinathus bangwensis have been used in the treatment of infectious and non-infectious diseases by the herbalist. This instigated evaluation of extract and fractions of Tapinathus bangwensis leaves for antimicrobial activity against some pathogenic organisms and identifications of the phytoconstituents. Methods: The standard phytochemical methods and GC-MS were used to identify the phytoconstituents of extract and fractions. The antimicrobial activity was determined using agar dilution method. Results: The phytochemical analysis revealed the presence of saponins, flavonoids, tannins, terpenoids and steroidal glycosides in the extract whereas n-hexane fraction contains terpenoids only, ethyl acetate contains flavonoids, tannins, terpenoids, saponins and n-butanol contains saponins, tannins and cardiac glycosides. The GC-MS analysis identified fatty acids, phthalic acid esters, saturated and unsaturated hydrocarbons in the extract and fraction. Most of the compounds identified possess antimicrobial, anticancer, antioxidant and cytotoxicity effects. However, the antimicrobial activity showed that Escherichia coli alone was susceptible to the extract with mics of 5 mg /ml. Escherichia coli, Salmonella typhi, Streptococcus pneumoniae, Proteus mirabilis, and Candidiaalbicans were susceptible to the n-hexane fraction which showed good activity with MIC range of 2.5-5 mg/ml. Escherichia coli, Staphylococcus aureus and Candida albicans were susceptible to ethyl acetate fraction with MIC range of 2.5-5mg/ml and Escherichia coli and Candida albicans were susceptible to ethyl acetate fraction with MIC range of 2.5-5mg/ml and Escherichia coli and candida albicans were susceptible to butanol fraction. with MIC range of 2.5-5mg/ml. klebsiella pneumoniae was not susceptible to the extract and any of the fractions. Conclusion: The findings provide justification for the use of Tapinathus bangwensis leaves as antimicrobial agent. Hence, the phytochemicals if isolated can serve as a template for the development of antimicrobial agent.

Sensibilidad in vitro de cepas chilenas de Cryptococcus neoformans de origen clínico / In vitro susceptibility of Chilean Cryptococcus neoformans strains of clinical source

Resumen Introducción: Las infecciones por levaduras del género Cryptococcus afectan principalmente a pacientes con déficit de la inmunidad mediada por células. Han sido escasos los estudios de sensibilidad realizados para este género en Chile. Objetivos: Determinar la sensibilidad in vitro de Cryptococcus sp a antifúngicos de uso habitual y evaluar la concordancia esencial entre sensibilidad determinada por microdilución en caldo y por difusión en agar con tiras comerciales. Materiales y Método: Estudio descriptivo de 21 cepas aisladas desde liquido céfalo-raquídeo y sangre. Las CIM50 y CIM90 para fluconazol, voriconazol y anfotericina B se determinaron por microdilución en caldo (Sensititre Yeast One®) y por difusión en agar con tiras comerciales (MIC Test Strips). Resultados: Todas las cepas correspondieron a C. neoformans. Los rangos de CIM50 y CIM90 para cada antifúngico estudiado fueron amplios por ambos métodos. La concordancia esencial entre microdilución y difusión en agar con tiras comerciales fue de 24, 62 y 29% para fluconazol, voriconazol y anfotericina B, respectivamente. Conclusiones: La prueba de Sensititre Yeast One® y la de difusión en agar con tiras comerciales, MIC Test Strips, tienen una pobre concordancia esencial para fluconazol y anfotericina B.

Abstract Background: Cryptococcus yeast infections primarily affect immunocompromised patients. There have been few susceptibility studies conducted for this genus in Chile. Aims: To determine the in vitro susceptibility to commonly used antifungals and evaluate the concordance between susceptibility determined by microdilution in broth and commercially available strips. Methods: Descriptive study of 21 Cryptococcus strains, isolated from cerebrospinal fluid and blood. The MIC50 and MIC90 for fluconazole, voriconazole and amphotericin B was determined by broth microdilution (Sensititre Yeast One®) and by commercial drug sensitivity strips (MIC Test Strips). Results: All strains corresponded to C. neoformans. The ranges of MIC50 and MIC90 for each antifungal studied were wide by both methods. The essential agreement between Sensititre Yeast One test and strips was 24, 62 and 29% for fluconazole, voriconazole and amphotericin B, respectively. Conclusions: The Sensititre Yeast One test and MIC Test Strips exhibited poor essential concordance, especially for fluconazole and amphotericin B.

Antifungal susceptibility testing for dermatophytes isolated from clinical samples by microbroth dilution method

Background: The cases of dermatophytoses have increased over the past few decades. Dermatophytoses affect the outer layers of skin, nails and hairs without tissue invasion. These infections are mostly not dangerous but, are important as public health problem particularly in the immunocompromised. The increased use of antifungal drugs for prolonged periods may lead to acquired antifungal resistance among previously susceptible strains. With this background present study was conducted to know the susceptibility pattern of dermatophytes.Methods: A total 35 isolates of dermatophytes isolated from clinically suspected cases of dermatophytoses were examined. Broth microdilution method M38-A2 approved protocol of CLSI (2008) for filamentous fungi was followed for determining the susceptibility of dermatophyte species to antifungal agents- itraconaole, fluconazole and ketoconazole.Results: Itraconazole minimum inhibitory concentrations (MIC) varied from 0.0156 to 1 µg/ml for all dermatophytes. T. rubrum species showed higher MIC range for Ketoconazole than T. mentagrophytes and T. tonsurans. Fluconazole had poor susceptibility for all dermatophytes by having higher MIC values.Conclusions: The MIC values observed in present study will help clinician to select an appropriate antifungal agent with minimal side effects. The data from present study can be useful as reference for future studies covering large no. of isolates and more drugs.

Antimicrobial Studies of Aqueous and Ethanolic Extracts of Enantia chlorantha Leaves and Stem Bark and Their Combined Effect on Selected Bacteria and Fungi.

Aim: To revalidate the antimicrobial effects of aqueous and ethanolic extracts of Enantia chlorantha leaves and stem bark against Enterococcus faecalis, Escherichia coli, Salmonella Typhi, Shigella sonnei, Staphylococcus aureus, Proteus vulgaris and Candida albicans; and to check the effects on the isolates when the stem bark and leave extracts are combined. Place and Duration of Study: Department of Biotechnology, School of Science, Federal University of Technology Owerri, Nigeria, between January 2013 and May 2013. Methodology: Agar well diffusion method was used for the susceptibility studies while the Minimum Inhibitory Concentrations were determined using the broth dilution method. The Minimum bactericidal/fungicidal concentration was determined by plating on nutrient agar. Results: The ethanolic extract of E. chlorantha stem bark showed antimicrobial activity on all 7 isolates tested with zones of inhibition in the range of 5mm to 33mm, while its aqueous extracts showed activity on only 3 of the 7 isolates with diameter zones of inhibition ranging between 5mm to 20mm. The aqueous leaf extracts showed activity against 3 of the 7 isolates while the ethanolic extracts had activity on 6. The minimum inhibitory concentration (MIC) of the ethanolic extract of both stem bark and leaves was between 1.56 and 12.5mg/ml, while that of aqueous extracts ranged from 6.25 to 12.5mg/ml. There was no obvious difference in the activity of the extracts when combined. Conclusion: This study validates potent antimicrobial activity of ethanol and aqueous extracts of Enantia chlorantha leaves and stem bark in line with similar studies. Further work is however needed to determine the toxicity of the plant extracts and also identify active components of the plant.

Antimicrobial resistance pattern and in vivo activity of azithromycin in Salmonella isolates.

We evaluated antimicrobial susceptibility pattern of 42 Salmonella isolates from February 2012 through January 2013. We also determined the minimum inhibitory concentrations (MICs) of azithromycin against Salmonella isolates and compared them with corresponding disc diffusion sizes. Entire 42 isolates were sensitive to chloramphenicol, 41 (97.6%) were sensitive to cotrimoxazole and amoxicillin each. MICs for azithromycin ranged from 2 μg/ml to 24 μg/ml, corresponding zone diameters ranged from 15 mm to 33 mm and the two were significantly correlated (P = 0.001). Our results indicate that whereas, azithromycin is a potential therapeutic option, the sensitivity to the first line drugs and absence of multidrug resistance reinforce the concept of antimicrobial recycling.

A new approach of real time polymerase chain reaction in detection of vancomycin-resistant enterococci and its comparison with other methods.

Background: Vancomycin-resistant enterococci (VRE) are third leading cause of nosocomial infection. Therefore, an effective, accurate and early detection of VRE along with their minimum inhibitory concentrations (MICs) is required to initiate appropriate therapy and thus better patient outcome. Objective: To detect VRE by real time quantitative polymerase chain reaction (Q-PCR) and to compare the results with chrom ID (C-ID) VRE and PCR. Further the study also determined the fold change of vanA gene by Q-PCR in different groups of VRE isolates classified on the basis of glycopeptides MIC range. Subjects and Methods: A total of 145 (80 VRE and 65 vancomycin-susceptible enterococci) clinical isolates were included in the study. After the screening of VRE isolates MICs were determined by E-test and agar dilution method. Further VRE was confirmed by vanA and vanB specific PCR and Q-PCR. Results: The sensitivity and specificity of C-ID VRE was 100% and 95.38%. However, sensitivity and specificity of conventional and Q-PCR were found to be 100%. Conventional and Q-PCR confirmed that our all isolates were vanA type. Mean R value was significantly higher ( P < 0.001) in group I (MIC > 1024 μg/ml) when compared to group II (MIC 512-1024 μg/ml) and group III (MIC < 512 μg/ml) isolates. The mean R was also significantly higher in group II when compared to group III isolates ( P = 0.038). Conclusion: Q-PCR is a rapid technique to detect vanA in enterococci along with their MIC range, thus it might be helpful to decide the treatment modalities of infections caused by VRE.

The Susceptibility Study of Fluconazole to Candida Species in Patients with Onychomycosis / 대한피부과학회지

BACKGROUND: With a growing number of people using a variety of medications, and suffering from systemic diseases, such as AIDS, Candida infection is also on the rise. This brings the issue of antifungal resistance into the spotlight. OBJECTIVE: This study sought to evaluate the detection of oral Candida and the change of minimum inhibitory concentration (MIC) in patients on oral fluconazole for treatment of onychomycosis. METHODS: We studied 25 patients who are on fluconazole for treatment of onychomycosis. We evaluated the MIC and detection of oral Candida at the time of the first visit, at the point of initial dosing, and subsequently, 12 and 24 weeks thereafter, and 12 weeks after the point of final dosing. RESULTS: At the first visit, we collected strains from the oral cavity. At 12 and 24 weeks thereafter, and 12 weeks after final dosing, C. albicans were detected in all cases. MIC measured at the corresponding time points revealed sensitivity in all cases with MIC under 8.0 microg/ml. After 12 and 24 weeks of administration, we identified the same strains at the oral cavity, and MIC of the two regions was elevated. At 12 weeks after the point of final dosing, MIC was decreased or remained the same at the three sites, and the result was the same at 12 and 24 weeks thereafter. CONCLUSION: The purpose of this study was to ascertain that the acquisition of resistance to fluconazole by oral Canadida is not as serious as we had anticipated; however, further studies based on larger patient pools would provide greater assurance.

Chemical Composition and Antibacterial Activity Against Oral Bacteria by the Essential Oil of Artemisia iwayomogi

The aerial part of Artemisia iwayomogi KITAMURA has traditionally been used for antitumour, immunomodulating, antimutagenic, antioxidant, antibacterial, antifungal, antipyretic, diuretic, liver protective effect, and choleretic purposes in Korea. The chemical composition of the essential oil obtained from A. iwayomogi was analyzed by GC/MS. The essential oil and its major compounds were tested for antibacterial activities against 15 different genera of oral bacteria. The essential oil of A. iwayomogi was rich in camphor (17.96%), 1,8-cineole (14.79%), terpinen-4-ol (3.28%), alpha-terpineol (17.60%), and beta-caryophyllene (4.05%). The essential oil of A. iwayomogi exhibited considerable inhibitory effects against all obligate anaerobic bacteria (MICs, 0.05 to 0.2 mg/ml; MBCs, 0.1 to 0.4 mg/ml) tested, while its major compounds demonstrated various degrees of growth inhibition.

Antimicrobial Activity of Extract and Fractions from Drynaria fortunei Against Oral Bacteria

One of the traditional Korean medicine, Drynaria fortunei (D. fortunei) is one of candidates known to be effective for the treatment of inflammation, hyperlipemia, arteriosclerosis, rheumatism, and gynecological diseases such as osteoporosis and bone resorption. The present study investigated the antimicrobial activity of methanol (MeOH) extract and n-butanol (n-BuOH), chloroform (CHCl3), and ethyl acetate (EtOAc) fractions of D. fortunei against oral bacteria. The n-BuOH and CHCl3 fractions (MICs, 0.0078 to 0.3125 mg/ml; MBCs, 0.019 to 0.625 mg/ml) were demonstrated as strong antibacterial activity than the MeOH extract and EtOAc fraction. The combination effects of n-BuOH fraction with ampicillin or gentamicin were synergistic against some oral bacteria. We suggest that D. fortunei could be employed as a natural antibacterial agent in oral care products.

In Vitro Antimicrobial Activities of Silver Nanoparticles (NANOVER) against Clinical Isolates / 대한임상미생물학회지

BACKGROUND: Silver has extensive and powerful antimicrobial activities and silver-containing materials have been widely used in many medical fields. Recently nanoparticulate silver was developed and it is superior to other types of silver in the antimicrobial activity and cytotoxicity. There have been no data from Korea on its antimicrobial activity, and we evaluated the antimicrobial activity of NANOVER against common clinical isolates. METHODS: Minimum inhibitory concentrations (MICs) of NANOVER for clinical isolates were determined using the agar dilution method of Clinical and Laboratory Standard Institute. A total of 45 isolates were tested including 4 reference strains (Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Enterococcus faecalis ATCC 29212), 5 strains of methicillin-resistant S.aureus (MRSA), 7 strains of methicillin-sensitive S. aureus (MSSA), 14 strains of E.coli,and 15 strains of P. aeruginosa. RESULTS: The MICs of S.aureus to NANOVER were under 12.5 microgram/mL regardless of the methicillin sensitivity or resistance. The other isolates showed the MICs under 12.5 to 6.25 microgram/mL. CONCLUSION: NANOVER has strong and extensive antimicrobial activities to common clinical isolates including those resistant to other antimicrobials.

Antimicrobial Activities Screening of 47 Traditional Chinese Herbal Medicine Extracts / 中国药房

OBJECTIVE:To determine the antimicrobial activity of alcoholic e xtracts of47traditional Chinese herbal medicines in vitro.METHODS:Antibiotic drug sensitive tests of Escherichia coli and Bacillus pyocyaneus were conducted,al?coholic extracts of47Chinese herbal medicines were prepared,which were subjected to bicteriostatic tests in vitro by agar spread routine method.RESULTS:Among the47traditonal Chinese herbal medicines alcoholic extracts,11of which did have antimicrobial activity against escherichia coli,pseudomonas aeruginosa and blastomyces albicans in different degree;among which,the antimicrobial activity of the alcoholic extracts of paeoniae radix and granatum to drug resistance bacteria were the highest,the alcoholic extracts of paeoniae radix showed strong inhibitory activities to the above3bacterium,especially to the resistant organisms with the minimum inhibitory concentrations(MIC)at1.3,1.1and1.8mg/ml respectively;The antimi?crobial activities of alchoholic extracts of granatum against the above3bacterium were also high with the MIC at8.3,3.6and2.3mg/ml respectively.CONCLUSION:The alcoholic extracts of paeoniae radix and granatum have broad spectrum of an?timicrobial activity and which have antimicrobial effect to drug resistance bacteria.