Antimicrobial activity of oregan and clove essential oils against some foodborne pathogens / Atividade antimicrobiona dos óleos essenciais de orégano e cravo frente a patógenos alimentares

The tendency to replace synthetic antimicrobials for natural ones in food industry and an increase in bacterial resistance to antibiotics resulted in a necessity to find new alternatives, and essential oils are emerging as promising substitutes for synthetic chemicals in food preservation. The objective of this work was to test the antimicrobial activity of oregano (OEO) and clove (CEO) essential oils over a range of bacteria, molds and yeast of importance as pathogens or food spoilage. The antimicrobial activity of oregano and clove essential oils were analyzed by disk diffusion method and broth microdilution test (MIC) of OEO and CEO were determined for each tested microorganism. OEO and CEO were evaluated in natura (IN) and after thermal processing (TP) at 120 o C for 5 min. Both OEO and CEO presented the same inhibition zones for IN and TP samples, for all tested microorganisms, indicating that these oils can be thermally processed maintaining their antimicrobial activity. For OEO and CEO, the more sensitive microorganisms were the fungi (Aspergillus niger, Penicillium citrinum and Candida albicans), followed by Staphylococcus aureus, Bacillus cereus and Methicillin - resistant Staphylococcus aureus (MRSA); the lowest antimicrobial activities were observed against Streptococcus mutans and Enterococcus faecalis. In general, OEO resulted in higher inhibition zones and lower MIC values for all tested microorganisms, suggesting that it was more effective as an antimicrobial agent than CEO (AU)

A preferência mundial para alimentos mais saudáveis e livres de aditivos químicos pelos consumidores, associada ao aumento da resistência bacteriana, resultaram na necessidade de medidas alternativas no setor de alimentos. Os óleos correspondem a antimicrobianos naturais e constituem uma classe emergente como substitutos dos produtos químicos sintéticos na conservação de alimentos. O objetivo deste trabalho foi avaliar a atividade antimicrobiana de óleos essenciais de orégano (OEO) e cravo (CEO ) frente a bactérias, fungos e leveduras de importância no setor de alimentos. OEO e CEO foram avaliados in natura (IN) e após processamento térmico (TP) a 120 o C por 5 minutos. Para avaliar a atividade antimicrobiana frente a cada microrganismo empregou-se o método de discodifusão e o teste de microdiluição em caldo (MIC). Tanto o OEO quanto o CEO apresentaram zonas de inibição semelhantes para amostras IN e TP, indicando que a atividade antimicrobiana desses óleos são resistentes a altas temperaturas. Os microrganismos mais sensíveis para ambos os óleos essenciais foram os fungos (Aspergillus niger, Penicillium citrinum e Candida albicans), seguidos por Staphylococcus aureus, Bacillus cereus e Staphylococcus aureus resistente à meticilina (MRSA). Já as cepas Streptococcus mutans e Enterococcus faecalis apresentaram uma maior resistência frente à atividade antimicrobiana dos óleos essenciais. Em geral, os maiores halos de inibição e menores valores de MIC foram obtidos quando empregado o OEO, sugerindo uma maior atividade microbiana do mesmo quando comparado ao CEO. (AU)

Detection of resistance to linezolid in Staphylococcus aureus infecting orthopedic patients.

Context: In today's medical scenario, the human race is battling the most intelligent enemy who has unending alternatives to combat with the potent elements they have produced against it. Aim: To study the resistance to linezolid among Staphylococcus aureus isolated from pus samples of orthopedic patients. Settings and Design: Pus samples were collected from dirty wounds of orthopedic patients undergoing long antimicrobial treatment programs. The sampling period was from July 2010 to June 2011. The samples were collected from different orthopedic hospitals of Nagpur (central India) representing a mixed sample of patients. Materials and Methods: One hundred pus samples were screened for S. aureus, by growth on mannitol salt agar (MSA), Baird-Parker agar (BPA), deoxyribonuclease test, tube coagulase test, and HiStaph latex agglutination test. Fifty-one S. aureus isolates were obtained which were further subjected to antimicrobial susceptibility testing by Kirby-Bauer disc diffusion method (DDM). Minimal inhibitory concentrations (MICs) were determined by an automated system, the VITEK 2 system. Also, Ezy MIC strip method was carried out in accordance with Clinical and Laboratory Standards Institute (CLSI) guidelines. Results and Conclusion: Twelve linezolid-resistant S. aureus (LRSA) isolates were recovered from 51 S. aureus cultures tested for susceptibility to linezolid using the DDM, VITEK 2 system, and Ezy MIC strip method. The emergence of resistance suggests nosocomial spread and abuse of antibiotic.

Antimicrobial Activities of Traditional Chinese Materia Medica Extracts / 中华医院感染学杂志

OBJECTIVE To discuss the antimicrobial activity of extracts from 10 kinds of traditional Chinese materia(medica)(TCMM)in vitro.METHODS Extracts from 10 kinds of TCMM were prepared,and subjected to(bacteriostatic) tests in vitro by test tube continuously dilution in order to observe their minimal inhibitory(concentration)(MIC),to Staphylococcus(aureus),Escherichia coli,Pseudomonas aeruginosa and Candida albicans.RESULTS Among the 10 kinds of TCMM extracts,which did have antimicrobial activity against S.aureus,E.coli,P.aeruginosa and C.albicans in(different) degree;among them,the antimicrobial(activit)y of the extracts of Radix Paeoniae Rubra,Punica granatum,Schisandra chinensis and Coptis chinensis to resistant bacteria was the highest,the extracts of(Radix) Paeoniae Rubra showed strong inhibitory activities to the above 4 bacteria,especially to the resistant(organisms) with the MIC at 7.8,1.95,1.95 and 7.8mg/ml,(respectively).CONCLUSIONS The extracts of Radix Paeoniae Rubra,P.granatum,S.chinensis and C.chinensis have broad spectrum of antimicrobial activity to(resistant) bacteria.

In vitro Antimicrobial Activity of Cefcapene against Clinical Isolates

BACKGROUND: Cefcapene pivoxil hydrochloride is a new oral cephem which has a broad-spectrum activity with expanded potency against Gram-positive bacteria, including Staphylococcus aureus and Streptococcus, as well as Gram-negative bacteria. In this study, we examined the in vitro activity of cefcapene against recently isolated clinical specimens from patients in a tertiary hospital. MATERIALS AND METHODS: We tested the in vitro antimicrobial activities of cefcapene and other cephalosporins against 450 clinical isolates from of patients in Asan Medical Center. Minimal inhibitory concentrations (MICs) were determined by agar dilution method according to the recommendations of National Committee for Clinical Laboratory Standards. RESULTS: Compared with other cephalosporins (cefaclor, cefpodoxime, and cefixime), cefcapene had lower MIC distributions for Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, and methicillin-susceptible S. aureus. Cefcapene had variable activity against Enterobateriaceae. CONCLUSION: Cefcapene had excellent in vitro antimicrobial activities against common typical bacterial respiratory tract pathogens and methicillin-susceptible S. aureus. Cefcapene appears to be a promising agent for treatment of community-acquired respiratory tract infections and infections caused by methicillin-susceptible S. aureus.

In vitro Antimicrobial Activity of Cefcapene against Clinical Isolates

BACKGROUND: Cefcapene pivoxil hydrochloride is a new oral cephem which has a broad-spectrum activity with expanded potency against Gram-positive bacteria, including Staphylococcus aureus and Streptococcus, as well as Gram-negative bacteria. In this study, we examined the in vitro activity of cefcapene against recently isolated clinical specimens from patients in a tertiary hospital. MATERIALS AND METHODS: We tested the in vitro antimicrobial activities of cefcapene and other cephalosporins against 450 clinical isolates from of patients in Asan Medical Center. Minimal inhibitory concentrations (MICs) were determined by agar dilution method according to the recommendations of National Committee for Clinical Laboratory Standards. RESULTS: Compared with other cephalosporins (cefaclor, cefpodoxime, and cefixime), cefcapene had lower MIC distributions for Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, and methicillin-susceptible S. aureus. Cefcapene had variable activity against Enterobateriaceae. CONCLUSION: Cefcapene had excellent in vitro antimicrobial activities against common typical bacterial respiratory tract pathogens and methicillin-susceptible S. aureus. Cefcapene appears to be a promising agent for treatment of community-acquired respiratory tract infections and infections caused by methicillin-susceptible S. aureus.