Analysis on Immune Tolerance and Resistance Mechanism of <i>Cryptococcus albidus</i>of AIDS Patients with Opportunistic Cryptococci Infection

Objective: To explore more about the immune tolerance and drug resistance of white Cryptococci albidus in AIDS patients with opportunistic Cryptococcus infection. Methods: To analyze drug resistance of the samples of white Cryptococcus albidus extracted from opportunistic infection AIDS patients in the certain infection area from October 2011 to December 2014. Results: After analyzing two samples of Cryptococcus albidus from 885 cases with opportunistic infection, we found that one of the samples do resist to ten common antibiotics. They were fluconazole, flu-cytosine, fluconazole, caspofungin, amphotericin B, MI miconazole, terbinafine, ketoconazole and itraconazole. The other one was sensitive to voriconazole, but resistant to the rest of the drug. Two strains of bacteria were inoculated into the animals in vivo and their DNA was extracted to carry out the genotyping analysis. The results showed that different degrees of resistance gene amplification bands were found in the 10 kinds of antibiotics. Conclusion: Although there were few opportunistic infection Cryptococcus albidus in AIDS patients, it was easy to show its resistance to drugs. Therefore, great attention should be paid to it for the medical workers.

Anti-yeast activities of Origanum oil against human pathogenic yeasts

Outbreak of autoimmune diseases by pathogenic yeasts has led to a serious medical threat. As these organisms evolve resistance to existing antifungal drugs, the concern could be further compounded. The realm of plant derived products offers a wide spectrum of potentially valuable alternatives to the existing synthetic fungicides. Essential oils from sev-eral medicinal plants have been shown to exhibit pharmacological attributes. In the present study, anti-yeast properties of Oregano essential oil (OEO) were examined in vitro against four human patho-genic yeasts i.e., Candida albicans, Cryptococcus al-bidus, Cryptococcus neoformans and Rhodotorula ru-brum. OEO concentration of 200 μg/mL was found to be growth inhibitory against all four yeasts examined, thereby showing its potential to function as a natural anti-yeast agent.

Sustainable Production of Microbial Lipids from Lignocellulosic Biomass Using Oleaginous Yeast Cultures

Microbial lipids derived from oleaginous yeast could be a promising resource for biodiesel and other oleochemical materials. The objective of this study was to develop an efficient bioconversion process from lignocellulosic biomass to microbial lipids using three types of robust oleaginous yeast: T. oleaginosus, L. starkeyi, and C. albidus. Sorghum stalks and switchgrass were utilized as feed-stocks for lipid production. Among oleaginous yeast strains, T. oleaginous showed better performance for lipid production using sorghum stalk hydrolysates. Lipid titers of 13.1 g·L-1 were achieved by T. oleaginosus, using sorghum stalk hydrolysates with lipid content of 60% (wt·wt-1) and high lipid yield of 0.29 g·g-1, which was substantially higher than the value reported in literature. Assessment of overall lipid yield revealed a total of 14.3 g and 13.3 g lipids were produced by T. oleaginosus from 100 g of raw sorghum stalks and switchgrass, respectively. This study revealed that minimization of sugar loss during pretreatment and selection of appropriate yeast strains would be key factors to develop an efficient bioconversion process and improve the industrial feasibility in a lignocellulose-based biorefinery.