1-Ethyl-3-methylimidazolium tolerance and intracellular lipid accumulation of 38 oleaginous yeast species.

Pretreatment with ionic liquids (IL) such as 1-ethyl-3-methylimidazolium chloride or acetate is an effective method for aiding deconstruction of lignocellulosic biomass; however, the residual IL remaining in hydrolysates can be inhibitory to growth of ethanologenic or oleaginous yeasts that have been examined in the literature. The aim of this study was to identify oleaginous yeasts that are tolerant of the IL [C2C1Im][OAc] and [C2C1Im]Cl using 45 strains belonging to 38 taxonomically diverse species within phyla Ascomycota and Basidiomycota. Yeasts were cultivated in laboratory medium supplemented with 0, 2, or 4% IL in 96-well plates. The eight most tolerant strains were then cultivated in 10-mL media with no IL, 242mM [C2C1Im][OAc], or 242mM [C2C1Im]Cl. The effects of [C2C1Im]+ exposure on cell mass production and lipid accumulation varied at the species and strain level. The acetate salt decreased cell biomass and lipid production more severely than did the chloride ion for six strains. Lipid output was not markedly different (2.1 vs. 2.3 g/L) in Yarrowia lipolytica UCDFST 51-30, but decreased from 5 to 65% in other yeasts. An equimolar concentration of the chloride salt resulted in much milder effects, from 25% decrease to 66% increase in lipid output. The highest lipid outputs in this media were 8.3 and 7.9 g/L produced by Vanrija humicola UCDFST 10-1004 and UCDFST 12-717, respectively. These results demonstrated substantial lipid production in the presence of [C2C1Im]Cl at concentrations found in lignocellulosic hydrolysates, and thus, these two strains are ideal candidates for further investigation.

Discovery of synthesis and secretion of polyol esters of fatty acids by four basidiomycetous yeast species in the order Sporidiobolales.

Polyol esters of fatty acids (PEFA) are amphiphilic glycolipids produced by yeast that could play a role as natural, environmentally friendly biosurfactants. We recently reported discovery of a new PEFA-secreting yeast species, Rhodotorula babjevae, a basidiomycetous yeast to display this behavior, in addition to a few other Rhodotorula yeasts reported on the 1960s. Additional yeast species within the taxonomic order Sporidiobolales were screened for secreted glycolipid production. PEFA production equal or above 1 g L-1 were detected in 19 out of 65 strains of yeast screened, belonging to 6 out of 30 yeast species tested. Four of these species were not previously known to secrete glycolipids. These results significantly increase the number of yeast species known to secrete PEFA, holding promise for expanding knowledge of PEFA synthesis and secretion mechanisms, as well as setting the groundwork towards commercialization.

Screening diabetic and hypertensive patients for ocular pathology using telemedicine technology in rural West Virginia: a retrospective chart review.

PURPOSE: There is a disparity between the number of people who need healthcare and availability of medical services in rural areas. This paper describes the experience of using telemedicine technologies for ophthalmologic evaluation in diabetic and hypertensive patients presenting to a community health center in rural West Virginia. METHODS: A registered nurse at a community health center in McDowell County, WV was trained to use a retinal camera to capture high-resolution digital images of the retina. Patients with diabetes or hypertension were screened during their routine primary care visits. Retinal photos were transmitted to an ophthalmologist for review and reports from the screenings were returned with instruction for follow-up care or specialist referral when indicated. FINDINGS: A retrospective chart review of 643 patients with diabetes or hypertension who were screened for ocular problems from October 2003 to December 2009 was completed. 44.8% of patients who were screened in the primary care center were identified as having 1 of 34 types of eye pathology that were previously unknown, of which 33% of patients were recommended to seek prompt attention by a retina consultant or glaucoma specialist for suspected ocular pathology. CONCLUSIONS: Our review demonstrates the actual benefits of telemedicine in the effective screening of diabetic and hypertensive patients for eye pathology, and our experience suggests that using distance medicine and telemedicine technologies is valuable for screening rural populations.

Cost-savings analysis of telemedicine use for ophthalmic screening in a rural Appalachian health clinic.

Life in mountainous, rural areas poses unique obstacles for ophthalmic care--notably, a lack of access to ophthalmologists and cost of care. Using telemedicine as a screening tool addresses both issues for diabetic retinopathy (DR) screening, as fundus photography has been determined to be sensitive and specific when screening for DR. The American Diabetes Association places a Grade E recommendation on fundus photography as a screening tool. We analyze the financial impact of ophthalmic telemedicine in a mountainous, rural health clinic in West Virginia over a seven year period from 2003-2009. At-risk patients are screened with a fundus camera during routine clinic visits, and the image is interpreted off-site by an ophthalmologist. Patients are either advised to follow up yearly or receive an immediate opthalmic referral. Considering the number of patients screened, travel costs, work missed, overhead, and billing considerations yields a savings of $153.43 per patient visit.

Ionic Liquid Tolerance of Yeasts in Family Dipodascaceae and Genus Wickerhamomyces.

In previous studies of ionic liquid (IL) tolerance of numerous species of ascomycetous yeasts, two strains of Wickerhamomyces ciferrii and Galactomyces candidus had unusually high tolerance in media containing up to 5% (w/v) of the 1-ethyl-3-methylimidazolium acetate ([C2C1Im][OAc]). The study aimed at investigating whether additional strains of these species, and additional species in the Dipodascaceae family, also possess IL tolerance, and to compare sensitivity to the acetate and chloride versions of the ionic liquid. Fifty five yeast strains in the family Dipodascaceae, which encompasses genera Galactomyces, Geotrichum, and Dipodascus, and seven yeast strains of species Wickerhamomyces ciferrii were tested for ability to grow in laboratory medium containing no IL, 242 mM [C2C1Im][OAc], or 242 mM [C2C1Im]Cl, and in IL-pretreated switchgrass hydrolysate. Many yeasts exhibited tolerance of one or both ILs, with higher tolerance of the chloride anion than of the acetate anion. Different strains of the same species exhibited varying degrees of IL tolerance. Galactomyces candidus, UCDFSTs 52-260, and 50-64, had exceptionally robust growth in [C2C1Im][OAc], and also grew well in the switchgrass hydrolysate. Identification of IL tolerant and IL resistant yeast strains will facilitate studies of the mechanism of IL tolerance, which could include superior efflux, metabolism or exclusion.