Aislamiento, identificación y evaluación de levaduras con potencial probiótico in vitro provenientes del suero de queso Paipa

El objetivo de este trabajo fue aislar e identificar levaduras del lactosuero del queso Paipa y evaluar su potencial probiótico (in vitro) para su uso en alimentación animal. Las cepas se aislaron en caldo extracto de levadura-glucosa-cloranfenicol, se purificaron en agar PDA y se caracterizaron molecularmente. Se aislaron 10 cepas dentro de las que se encuentran Candida kefyr, Kluyveromyces marxianus, Pichia fermentans, entre otras. Las levaduras aisladas fueron evaluadas para evidenciar su uso potencial como probióticos en alimentación animal. Se determinó la resistencia a sales biliares (0,05, 0,1, 0,15, 0,20, 0,25 y 0,30 %), la estabilidad al pH del estómago (1,5, 2,0, 2,5, 3,0, 3,5 y 4,0) y resistencia al jugo gástrico (pH 1,5, NaCl de 0,2 % y pepsina de 0,32 %). En la prueba con diferentes concentraciones de sales biliares, las mejores cepas fueron K. marxianus (30_4) y P. fermentans (28_5). En la prueba de pH, el mejor desempeño lo tuvieron P. marxianus (30_4) y Yarrowia lipolytica. Finalmente, en la prueba de jugos gástricos se destacaron C. kefyr y K. marxianus (R_1). Las cepas que presentaron buen desempeño en casi todas las pruebas fueron K. marxianus (30_4) y P. fermentans (28_5), de tal forma que estas levaduras aisladas del lactosuero de queso Paipa tienen potencial en la aplicación como probióticos en la alimentación animal.

Ocena działania olejku jałowcowego (Juniperi aetheroleum) wobec grzybów drożdżopodobnych

Introduction. Juniper has been known and often used in folk medicine since ancient times. The extracts and essential oil of this plant’s fruit exhibit anti-inflammatory, antioxidant, anticancer, blood pressure lowering, antiarthritic, antirheumatic activity and are helpful in Alzheimer’s disease. Fruits contain essential oil (α-pinene, limonene, β-pinene, terpinen-4-ol, sabinene, β-phellandrene, α-terpinene, myrcene, γ-terpinene); organic acids, flavonoids and tannins. Juniper oil shows antimicrobial activity. Aim. The aim of this research was evaluating activity of juniper oil against yeast-like fungi isolated from the oral cavity. Material and methods. The study included 31 strains of fungi belonging to the following species: Candida albicans (14 strains), Candida glabrata (3), Candida guilliermondii (1), Candida humicola (1), Candida kefyr (2), Candida krusei (2), Candida lusitaniae (1), Candida parapsilosis (3), Candida tropicalis (3), Candida utilis (1) and 9 reference strains from genus: C. albicans ATCC 10231, C. glabrata ATCC 66032, C. guilliermondii ATCC 6260, C. kefyr, ATCC 4130, C. krusei ATCC 14249, C. lusitaniae ATCC 34499, C. parapsilosis ATCC 22019, C. tropicalis ATCC 750 i C. utilis ATCC 9958. The susceptibility (MIC) of fungal strains to juniper oil was determined by the method of serial dilution technique in Sabouraud’s agar. At first, the oil was diluted in DMSO, then in distilled water. The tested concentrations were: 20.0, 15.0, 10.0, 7.5 and 5.0 mg/ml. The suspension containing 105 CFU/per drop was transferred by a Steers replicator to the surface of Sabouraud’s agar with or without juniper oil (strains growth control). Incubation was carried out at 37°C for 24-48 hrs under aerobic conditions. The lowest concentration of oil that completely inhibited the growth of the tested yeast-like fungi was taken as the MIC. Results. The results indicated, that the strains of Candida guilliermondii and C. utilis were the most sensitive to juniper oil. The growth of these strains was inhibited at a concentration of 10.0 mg/ml. The 2 species of strains C. glabrata and Candida lusitaniae were sensitive to a concentration of 15.0 mg/ml. The juniper oil was less active against Candida kefyr strains (MIC – 7.5-> 20.0 mg/ml). Fungi from genus of C. krusei, Candida parapsilosis and C. tropicalis were susceptible to concentrations in the range 10.0-≥ 20.0 mg/ml. The Candida albicans strains were characterized by moderate susceptibility. The growth of the 50% strains was inhibited at concentration 15.0 mg/ml and another 50% strains at 20.0 mg/ml. Of all the yeast-like fungi strains tested only 1 strain was sensitive to the low concentration of 7.5 mg/ml, and another 5 strains to 10.0 mg/ml. The growth of 39% of fungi strains was inhibited at the concentration of 15.0 mg/ml and 42% at concentration 20.0 mg/ml of the oil and more. Conclusions. Candida guilliermondii and C. utilis showed the highest sensitivity to juniper oil. The Candida albicans strains were characterized by moderate susceptibility. The juniper oil showed the lowest activity against Candida humicola species.

Speciation and antifungal susceptibility testing of candida species isolated from clinical samples

Background: The importance of epidemiological monitoring of yeasts involved in pathogenic processes is unquestionable due to the increase in trend of infections caused by various species of Candida over the last decade; so are the changes observed in species causing Candidiasis and empirical antifungal treatment. Aims and Objective: To speciate the clinically isolated Candida species by phenotypic methods and to estimate the antifungal susceptibility of the isolated species against fluconazole, ketoconazole, voriconazole, itraconazole by disc diffusion method. Materials and Methods: A cross-sectional study conducted in 2018 in the Department of Microbiology, J. N. Medical College, KAHER, Belagavi Karnataka. Ethical Clarence was obtained from institutional ethical committee J.N. Medical College. Results: Out of 59 Candida isolates, Candida tropicalis was the predominant species 41(69.49%), followed by Candida glabrata 5 (8.47%), Candida parapsilosis and Candida lusitaniae 4 (6.78%) respectively, Candidaguilliermondii and Candida kefyr 2 (3.39%) respectively and the least one was Candida krusei 1 (1.69%). Voriconazole showed the highest level of sensitivity whereas Itraconazole has shown the least sensitivity pattern by disk diffusion method. Out of 59 Candida species, 52 (88.13%) were sensitive to Voriconazole, 44 (74.57%) were sensitive to Fluconazole, 40 (67.79%) were sensitive to Ketoconazole and the least sensitivity was shown by Itraconazole 30 (50.84%). Candida krusei and Candida guilliermondii showed 100% sensitive to Fluconazole, Voriconazole, Ketoconazole and Itraconazole respectively. Conclusion: Non-albicans Candida species are being common isolates from cases of candidiasis. Candida tropicalis is the predominant isolate, followed by Candida glabrata, Candida lusitaniae, Candida parapsilosis, Candida guilliermondii, Candida kefyr and Candida krusei. Most of the isolates were sensitive to Voriconazole.