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Biosurfactants are amphipathic molecules with considerable potential for application in different industries due to their biochemical characteristics, low toxicity as well as greater biodegradability and stability compared to chemical surfactants when submitted to adverse environmental conditions. The aim of the present study was to investigate the production of a biosurfactant by Candida lipolytica UCP 0988 grown in a medium containing 4.0% molasses, 2.5% used soybean frying oil, and 2.5% corn steep liquor for 144 h at 200 rpm. The biosurfactant was characterized; its stability and toxicity were investigated, and the compound was applied in oil removal tests. In the C. lipolytica growth and biosurfactant production studies, the surface tension of the medium was reduced from 72 mN/m to 25 mN/m, the critical micellar concentration (CMC) was 0.5 g/L (w/v), and the yield was 12 g/L. Tests under extreme conditions of temperature, pH, and NaCl indicated the stability of the biosurfactant. Fourier-transform infrared and nuclear magnetic resonance spectroscopy of the chemical structure of the purified biosurfactant suggested that the biosurfactant is a glycolipid. The anionic biosurfactant exhibited no toxicity to the microcrustacean Artemia salina or vegetable seeds (Brassica oleracea). Dispersion tests in seawater demonstrated 100% efficiency of the biomolecule against motor oil. The biosurfactant was efficient at removing oil from sand in static and kinetic tests at concentrations of ½ CMC (0.25 g/L), CMC (0.5 g/L), and 2 × CMC (1.0 g/L), with removal rates of 70 to 96%, whereas the synthetic surfactants tested removed only 10 to 18% of the oil. Based on the findings, the biosurfactant analyzed has considerable potential for the remediation of contaminated coastal and marine environments due to oil spills.

Biosurfactants are amphipathic molecules with considerable potential for application in different industries due to their biochemical characteristics, low toxicity as well as greater biodegradability and stability compared to chemical surfactants when submitted to adverse environmental conditions. The aim of the present study was to investigate the production of a biosurfactant by Candida lipolytica UCP 0988 grown in a medium containing 4.0% molasses, 2.5% used soybean frying oil, and 2.5% corn steep liquor for 144 h at 200 rpm. The biosurfactant was characterized; its stability and toxicity were investigated, and the compound was applied in oil removal tests. In the C. lipolytica growth and biosurfactant production studies, the surface tension of the medium was reduced from 72 mN/m to 25 mN/m, the critical micellar concentration (CMC) was 0.5 g/L (w/v), and the yield was 12 g/L. Tests under extreme conditions of temperature, pH, and NaCl indicated the stability of the biosurfactant. Fourier-transform infrared and nuclear magnetic resonance spectroscopy of the chemical structure of the purified biosurfactant suggested that the biosurfactant is a glycolipid. The anionic biosurfactant exhibited no toxicity to the microcrustacean Artemia salina or vegetable seeds (Brassica oleracea). Dispersion tests in seawater demonstrated 100% efficiency of the biomolecule against motor oil. The biosurfactant was efficient at removing oil from sand in static and kinetic tests at concentrations of ½ CMC (0.25 g/L), CMC (0.5 g/L), and 2 × CMC (1.0 g/L), with removal rates of 70 to 96%, whereas the synthetic surfactants tested removed only 10 to 18% of the oil. Based on the findings, the biosurfactant analyzed has considerable potential for the remediation of contaminated coastal and marine environments due to oil spills. [ABSTRACT FROM AUTHOR]

AbstractIn this study, the bioaccumulation of Cu(II) ion by Rhizopus delemar and Candida lipolytica was investigated and the bioaccumulation and biosorption of Cu(II) ions by Candida lipolytica compared. The specific growth rate and the maximum microorganism concentration of both microorganisms increased with increasing initial molasses concentration whereas decreased with increasing initial Cu(II) ion concentrations up to 250 mg/L. Accoding to Monod equation, the maximum specific growth rate and saturation constant for C. lipolytica and R. delemar were determined as 0.335 h−1-32.330 g/L and 0.406 h−1-24.182 g/L, respectively. The bioaccumulation efficiencies of R. delemar and C. lipolytica were determined as 74.18% and 67.30% in the presence of 50 mg/L Cu(II), respectively. At pH 4.0, the maximum biosorption rate (4.72 mg/g min) and the biosorbed Cu(II) ion concentration (49.0 mg/L) were obtained for C. lipolytica and these values increased with increasing Cu(II) concentration. Cu(II) biosorption by C. lipolytica fitted well to the Langmuir isotherm model and pseudo-second-order kinetic model and maximum adsorption capacity was found as 114.942 mg/g. The bioaccumulated Cu(II) was found to be 21.5 mg/g whereas the amounts of biosorbed Cu(II) were calculated as 53 mg/g by C. lipolytica at a concentration of 100 mg/L of Cu(II). [ABSTRACT FROM AUTHOR]

Biotechnological processes, particularly those involved in biosurfactant production, can pose significant financial challenges. The viability of biosurfactant production hinges on the creation of processes that make use of cost-effective raw materials. This study focuses on exploring the potential of Candida lipolytica ICCF 214 (ATCC 16618) reference strain for biosurfactant production using a mixture of vegetable oil and other chemical compounds used for fermentation medium (1% glutamic acid, urea, or glucose) as carbon sources. Based on the obtained results, we can conclude that all three fermentation media stimulated Candida lipolytica ICCF 214 strain to produce biosurfactants, but further analysis of surface tension and antimicrobial activity of the obtained biosurfactants is required. Additionally, we observed that media with a volume of 100 ml produced higher quantities of biosurfactants, due to the good aeration of the fermentation medium. However, even the ones with 150 ml showed decent performance during the bioprocess. [ABSTRACT FROM AUTHOR]

ABSTRACT The antifungal susceptibility profile and epidemiological cut-off values (ECOFFs) of Yarrowia lipolytica, a rare opportunistic yeast, remain unclear. We conducted a comprehensive multi-method study on clinical isolates from various central hospitals, based on the China Hospital Invasive Fungal Surveillance Network (2009–2022). Our objective was to evaluate the antifungal susceptibility of Y. lipolytica, establish its local ECOFFs (L-ECOFFs), and compare the performance of the ATB FUNGUS 3 (ATB), Sensititre YeastOne (SYO), and minimum inhibitory concentration (MIC) test strip (MTS) with that of the broth microdilution (BMD) method. L-ECOFFs were established using ECOFFinder, and we examined ERG11 mutations to assess the reliability of the L-ECOFFs. The L-ECOFF for fluconazole was 8 µg/mL. Non-wild-type isolates of antifungal drugs, such as flucytosine and azoles, were exclusively isolated from patients. Additionally, we detected that four strains with the ERG11 A395T mutation (azole MIC >L-ECOFF) may be associated with the exposure to azole drugs. For azoles, ATB showed the highest essential agreement with the BMD (98.18%–100%), followed by SYO (85.45%–100%). However, ATB could not detect susceptibility to echinocandins, while SYO exhibited the highest agreement (98.18%–100%) in detecting echinocandin susceptibility. Our findings indicate that acquired azole cross-resistance has emerged despite Y. lipolytica infections being rare. This research provides crucial antifungal susceptibility data and establishes the initial L-ECOFFs for Y. lipolytica. The SYO is recommended as the optimal laboratory antifungal susceptibility testing method for Y. lipolytica, followed by ATB, whereas the use of MTS requires caution. We hope that this study will facilitate improved clinical management of Y. lipolytica infections. IMPORTANCE Yarrowia lipolytica, also known as Candida lipolytica, is an emerging opportunistic “rare pathogenic yeast”. Due to the limited data on its antifungal susceptibility, the clinical treatments become challenging. Based on the China Hospital Invasive Fungal Surveillance Network (2009–2022), we conducted a comprehensive multi-method study on clinical isolates from various central hospitals. This study is currently the largest study carried out to assess the antifungal susceptibility of Y. lipolytica. It is also the first to establish local epidemiological cut-off values (L-ECOFFs), identify its ERG11 mutations, and assess the consistency between the three prevalent commercial antifungal susceptibility testing methods and the broth microdilution method. We recommend the Sensititre YeastOne as the best option for antifungal susceptibility testing for Y. lipolytica, followed by the ATB FUNGUS 3. Nevertheless, practitioners should use the MIC test strip with discretion.

ULVA selenium nanoparticles (USeNPs) were synthesized and characterized, then examined for their wound healing capacity through in vitro assay showing promising healing (82.27%) with USeNPs concentration (500µg/mL). We also determined the antifungal potential via agar well diffusion technique, minimum inhibitory concentration (MIC), which was evaluated by a micro-dilution assay. The synergistic effect of the USeNPs individually or in combination with standard antifungal antibiotic (ketoconazole;100μg/mL) was studied against Cryptococcus neoformans RCMB 0049001 and Candida lipolytica RCMB 005007(1). Geotrichum candidum RCMB 041001 was also checked by agar well diffusion assay, followed by transmission electron microscopy to assess different changes in the most sensitive fungal yeast cells. The results indicated that USeNPs have a promising antifungal effect against C. neoformans RCMB 0049001 and C. lipolytica RCMB 005007(1) by achieving remarkable inhibition zones. In comparison, no effect was detected on G. candidum RCMB 041001. The MIC was found to be 78.1μg and 312.5μg for C. neoformans RCMB 0049001 and C. lipolytica RCMB 005007(1), respectively. The biosynthetic USeNPs have a strong antifungal potential and can elevate and strengthen the action of ketoconazole antibiotic towards different fungal pathogens, and this was obvious In the experiment of synergism carried out in the present study based on combining ketoconazole;100μg/mL with USeNPs, which resulted in a detached C. neoformas RCMB 0049001 cells with a severe dramatic change. [ABSTRACT FROM AUTHOR]

[Display omitted] • Black soldier fly larvae are not effective in lipid removal and transformation. • Fungi enrichment is capable of improving lipid bioconversion rate by BSFL. • Candida Lipolytica was superior fungus for the lipid bioconversion improvement. • Candida Lipolytica facilitated lipid transformation through fatty acid assimilation. • BSFL retrieved from food waste obtained high yield of polysaturated fatty acid. Food waste can be converted into insectile fatty acids (FAs) by the larvae of black soldier fly (BSFL), Hermetia illucens , for use in the feed sector or as a source of biodiesel. However, waste oil was less decomposed than carbohydrate or protein in frass due to the limitation of larval lipid metabolism. In this study, 10 yeast strains were screened, corresponding to six species, to examine their capacity of improving lipid transformation performance by BSFL. The species of Candida lipolytica was superior to the other five species, which exhibited significantly higher lipid reduction rate (95.0–97.1 %) than the control (88.7 %), and the larval FA yields achieved 82.3–115.5 % of the food waste FA matters, suggesting that BSFL not only transformed waste oil but also biosynthesized FAs from waste carbohydrate and other substances. Further, the CL2 strain of Candida lipolytica was examined for treating food waste containing high lipid content (16–32 %). The lipid removal rate was found improved from 21.4 to 42.3 % (control) to 80.5–93.3% in the waste containing 20–32 % lipid. The upper limit of lipid content that could be endured by BSFL was ≈16 %, and the CL2-enrichment elevated the upper limit to ≈24 %. Fungal community analysis indicated that Candida spp. accounted for the lipid removal improvement. The Candida spp. CL2 strain may facilitate the lipid reduction and transformation by BSFL through microbial catabolizing and assimilation of waste FAs. Altogether, this study suggests that yeast enrichment is feasible in improving lipid transformation by BSFL especially for food waste exhibiting high lipid content. [ABSTRACT FROM AUTHOR]

Candida lipolytica is an uncommon Candida species causing invasive fungemia. This yeast is mainly associated with the colonisation of intravascular catheters, complicated intra-abdominal infections, and infections in the paediatric population. Here, we report a case of C. lipolytica bloodstream infection in a 53-year-old man. He was admitted for an alcohol withdrawal syndrome and mild COVID-19. Among the primary risk factors for candidemia, only the use of broad-spectrum antimicrobials was reported. The empiric treatment was commenced with caspofungin and then targeted with intravenous fluconazole. Infective endocarditis was ruled out using echocardiography, and PET/TC was negative for other deep-seated foci of fungal infection. The patient was discharged after blood culture clearance and clinical healing. To the best of our knowledge, this is the first case of C. lipolytica candidemia in a patient with COVID-19 and alcohol use disorder. We performed a systematic review of bloodstream infections caused by C. lipolytica. Clinicians should be aware of the possibility of C. lipolytica bloodstream infections in patients with alcohol use disorder, especially in a COVID-19 setting. [ABSTRACT FROM AUTHOR]

Atypical Candida spp. infections are rising, mostly due to the increasing numbers of immunocompromised patients. The most common Candida spp. is still Candida albicans; however, in the last decades, there has been an increase in non-Candida albicans Candida species infections (e.g., Candida glabrata, Candida parapsilosis, and Candida tropicalis). Furthermore, in the last 10 years, the reports on uncommon yeasts, such as Candida lusitaniae, Candida intermedia, or Candida norvegensis, have also worryingly increased. This review summarizes the information, mostly related to the last decade, regarding the infections, diagnosis, treatment, and resistance of these uncommon Candida species. In general, there has been an increase in the number of articles associated with the incidence of these species. Additionally, in several cases, there was a suggestive antifungal resistance, particularly with azoles, which is troublesome for therapeutic success. [ABSTRACT FROM AUTHOR]

Candida lipolytica is an uncommon Candida species causing invasive fungemia. This yeast is mainly associated with the colonisation of intravascular catheters, complicated intra-abdominal infections, and infections in the paediatric population. Here, we report a case of C. lipolytica bloodstream infection in a 53-year-old man. He was admitted for an alcohol withdrawal syndrome and mild COVID-19. Among the primary risk factors for candidemia, only the use of broad-spectrum antimicrobials was reported. The empiric treatment was commenced with caspofungin and then targeted with intravenous fluconazole. Infective endocarditis was ruled out using echocardiography, and PET/TC was negative for other deep-seated foci of fungal infection. The patient was discharged after blood culture clearance and clinical healing. To the best of our knowledge, this is the first case of C. lipolytica candidemia in a patient with COVID-19 and alcohol use disorder. We performed a systematic review of bloodstream infections caused by C. lipolytica. Clinicians should be aware of the possibility of C. lipolytica bloodstream infections in patients with alcohol use disorder, especially in a COVID-19 setting.

Contamination caused by hydrocarbons can produce permanent and irreparable damage to the environment. Biosurfactants' production has been intensively studied in the last years, for these agents are biodegradable and have applications in several industrial sectors. Moreover, they have, as well, managed to be ecologically compatible and to carry out the biodegradation of hydrophobic pollutants without damaging the environment. Bioremediation involves using microorganisms or their microbial metabolites for the degradation of contaminants, avoiding the use of chemicals. Biosurfactants are amphipathic biomolecules produced by microorganisms capable of allowing water-oil interaction and also providing biostimulation in the degradation process. In this work, it was used a medium formulated with distilled water supplemented with 2.5% corn steep liquor, 4.0% molasses, and 2.5% frying oil as substrates used to produce a biosurfactant Candida lipolytica (UCP 0988), at 28 ºC during 144 hours under 200 rpm. The biosurfactant's tensoactive properties were determined, and its isolation, toxicity, and bioremediation application were described. The surface tension values indicated a reduction in water tension from 72 to 28 mN/m and a yield of 21g/L in biosurfactant and Critical Micellar Concentration (CMC) of 0.5%. The biosurfactant produced demonstrated stability concerning emulsification and surface tension in extreme pH values (2 to 12), concentrations of NaCl (2 to 10%), and different temperatures (5 to 120°C), and it did not present toxicity to the vegetables. The crude or isolated biosurfactant showed efficiency in removing 57% - 70% of the motor oil in contaminated soil under static conditions. The results obtained demonstrated biosurfactant produced by C. lipolytica showed promising properties for use in bioremediation of hydrophobic compounds. [ABSTRACT FROM AUTHOR]

Aim: The aim of the study was to analyze the selected nanomechanical properties of Candida spp: Candida albicans (standard strain ATCC 10231), Candida albicans (clinical strain, cultured from an oral swab), Candida lipolytica (clinical strain, cultured from a nosal swab) in atomic force microscopy (AFM). Material/Methods: The culture Candida spp. was performed of Tryptone Soya Broth (BioMaxima). The topography and sample properties were analysed in AFM (Ntegra Spectra C from NT) and the results were carried out using NOVA 1.1.0.1824 software. Results: C. albicans ATCC 10231 cells were significantly higher 1.81 µm (p = 0.001) from clinical strains: C. albicans (1.30 µm) and C. lipolytica (1.23 µm). C. albicans ATCC 10231 cells, and C. albicans cells of the clinical strain were softer, especially in the top parts of cells, than C. lipolytica cells. Adhesion force measured for C. albicans ATCC 10231 was 62.83 nN, and was significantly higher compared to the values obtained for C. albicans (41.93 nN, p = 0.0002) and C. lipolytica (41.78 nN, p = 0.0002). The stiffness of the Candida spp. cell surface was comparable and was in the range of 5-6 nA. Conclusions: The differences in height may result from different conditions in which clinical strains grow. Adhesion force can be helpful in the analysis of the degree of destruction of the cell wall by various substances. The conducted analyses showed morphological differences and the differences in mechanical properties of the researched Candida spp. This data may be important in assessing their susceptibility to the effects of various substances of a lytic nature. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the potential application of the biosurfactant from Candida lipolytica grown in low-cost substrates, which has previously been produced and characterized under optimized conditions as an adjunct material to enhance the remediation processes of hydrophobic pollutants and heavy metals generated by the oil industry and propose the formulation of a safe and stable remediation agent. In tests carried out with seawater, the crude biosurfactant demonstrated 80% oil spreading efficiency. The dispersion rate was 50% for the biosurfactant at a concentration twice that of the CMC. The biosurfactant removed 70% of motor oil from contaminated cotton cloth in detergency tests. The crude biosurfactant also removed 30–40% of Cu and Pb from standard sand, while the isolated biosurfactant removed ~30% of the heavy metals. The conductivity of solutions containing Cd and Pb was sharply reduced after biosurfactants' addition. A product was prepared through adding 0.2% potassium sorbate as preservative and tested over 120 days. The formulated biosurfactant was analyzed for emulsification and surface tension under different pH values, temperatures, and salt concentrations and tested for toxicity against the fish Poecilia vivipara. The results showed that the formulation had no toxicity and did not cause significant changes in the tensoactive capacity of the biomolecule while maintaining activity demonstrating suitability for potential future commercial product formulation.

Candida lipolytica with efficient decolorization of Acid Red 3 G was screened. An experimental design based on the response surface method was applied to finding the optimal conditions. The results showed that the optimum dye decolorizing conditions were 160 r/min with shake cultivation, initial dye concentration (400 mg/ L) , incubation temperature 30 °C with inoculum amount 5 % , and the medium compositions were glucose 21 g/L, yeast extract 10 g/L, Mg2+ 20 mmol/L, and Cu2+ 9. 5 mg/L. The Candida lipolytica culture exhibited decolorization 97. 5 % within 48 h. These results demonstrated that the Candida lipolytica culture had high potential to decolorize azo dyes textile-dyeing wastewater. [ABSTRACT FROM AUTHOR]

Background: Biotechnological processes are costly, especially for the production of biosurfactants. The successful production of a biosurfactant is dependent on the development of processes using low cost raw materials. Considering the importance of the characteristics of a biosurfactant to facilitate its industrial application, the properties of the biosurfactant produced by Candida lipolytica through previously optimized medium have been established. Results: The yeast was grown for 72 h to determine the kinetics of growth and production. The surface tension of the cell-free broth was reduced from 55 to 25 mN/m. The yield of biosurfactant was 8.0 g/l with a CMC of 0.03%. The biosurfactant was characterized as an anionic lipopeptide composed of 50% protein, 20% lipids, and 8% of carbohydrates. Conclusions: The isolated biosurfactant showed no toxicity against different vegetable seeds: Brassica oleracea, Solanum gilo and Lactuca sativa L. and the micro-crustacean Artemia salina. The properties of the biosurfactant produced suggest its potential application in industries that require the use of effective compounds at low cost.

In this study, Candida lipolytica lipase ( CLL ) was immobilized on magnetic multi-walled carbon nanotubes (mMWCNTs) via hydrophobic and cation-exchange interaction. The resultant immobilized CLL showed much better thermal stability, biocatalyst activity and easier recycling than the free form. A method for efficient enzymatic acidolysis of tripalmitin (PPP) with oleic acid (OA), to produce OPO-rich TAGs, was developed, using the immobilized CLL as the biocatalyst. Under optimized conditions (2% water, 20 mg/ml enzyme, 1:6 PPP/OA, 50 °C, 2 h), the content of OPO in the final product reached 46.5%. CLL @mMWCNTs had a better activity and manipulative stability than commercial lipases. More importantly, the feasibility of CLL @mMWCNTs was also validated in the practical production of OPO-rich TAGs, using lard and restructured palm oil as the raw material. These results suggest that CLL @mMWCNTs is a promising biocatalyst for the OPO-rich TAGs production and will be helpful for the infant formula industry. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the potential application of the biosurfactant from Candida lipolytica grown in low-cost substrates, which has previously been produced and characterized under optimized conditions as an adjunct material to enhance the remediation processes of hydrophobic pollutants and heavy metals generated by the oil industry and propose the formulation of a safe and stable remediation agent. In tests carried out with seawater, the crude biosurfactant demonstrated 80% oil spreading efficiency. The dispersion rate was 50%for the biosurfactant at a concentration twice that of the CMC. The biosurfactant removed 70% of motor oil from contaminated cotton cloth in detergency tests. The crude biosurfactant also removed 30-40% of Cu and Pb from standard sand, while the isolated biosurfactant removed ~30% of the heavy metals. The conductivity of solutions containing Cd and Pb was sharply reduced after biosurfactants' addition. A product was prepared through adding 0.2% potassium sorbate as preservative and tested over 120 days. The formulated biosurfactant was analyzed for emulsification and surface tension under different pH values, temperatures, and salt concentrations and tested for toxicity against the fish Poecilia vivipara. The results showed that the formulation had no toxicity and did not cause significant changes in the tensoactive capacity of the biomolecule while maintaining activity demonstrating suitability for potential future commercial product formulation. [ABSTRACT FROM AUTHOR]

This large-scale production, toxicity, characterization and economic analysis of the biosurfactant from Candida lipolytica UCP 0988 produced in the low-medium formulated with animal fat and corn steep liquor was investigated. The biosurfactant was produced in the stationary phase under 200 rpm in the absence of aeration and reduced the surface tension of the medium from 50 to 28 mN/m after 96 h, yielding 10.0 g/L of isolated biosurfactant in a 2 L bioreactor. The production was maximized in a 50 L bioreactor, reaching 40 g/L biosurfactant and 25 mN/m. The cell biomass was quantified and characterized for use in animal nutrition. Chemical structures of the biosurfactant were identified using FTIR and NMR. The crude biosurfactant was not toxic to the bivalve Anomalocardia brasiliana , to the microcrustacean Artemia salina, or three species of vegetables seeds. The biosurfactant stimulated the degradation of motor oil by the seawater indigenous microorganisms. The results obtained indicate that the biosurfactant produced has great potential to be applied as a bioremediation agent for cleaning oil spills. [ABSTRACT FROM AUTHOR]

Goat milk fat is known for the higher content of short- and medium- chain fatty acids, which have antibacterial and antifungal properties. By solid state enzymatic hydrolysis of goat milk fat, using different Candida lipolytica strains as lipase sources, were obtained hydrolysate products with antimicrobial activity. The antimicrobial properties of hydrolysates against some spoilage microorganisms, bacteria (Bacillus subtilis, Bacillus cereus) and fungi (Saccharomyces cerevisae, Candida mycoderma, Rhodotorula glutinis, Aspergillus niger, Penicillium spp. and Geotrichum candidum) were evaluated. Hydrolysate extracts produced by hydrolysis activity of Candida lipolytica G.01.3.1strain exerted inhibitory effect against bacteria, as well as fungi. The results of this study could be considered promising for developing new natural preservatives that could be used in food industry in order to reduce food contamination, increase the shelf life and for food safety assurance. [ABSTRACT FROM AUTHOR]

Detailed analyses of the biodegradation of 1-alkoxy-2,4-dichlorobenzenes by Yarrowia lipolytica KCTC 17618 were conducted by gas chromatography-mass spectrometry. Eight different 1-alkoxy-2,4-dichlorobenzenes with a linear alkylgroup (butyl to tetradecyl) were subjected to liquid culture. Y. lipolytica could rapidly metabolize short-chain analogues (butyl to hexyl) and utilize them as the sole carbon source for growth, whereas the analogues with longer alkyl groups were unable to support the growth but gradually metabolized in the nutrient media. The metabolic rates decreased with an increase of alkyl chain length up to a decyl group. Comprehensive metabolite analysis indicated that 4-(2,4-dichlorophenoxy)-butyric acid was the final metabolite of substrates with even-numbered alkoxy groups. 4-(2,4-dichlorophenoxy)-butyric acid is a well-known plant growth regulator and herbicide. In case of odd-numbered alkoxybenzenes, 3-(2,4-dichlorophenoxy)-propionic acid was the most abundant metabolite and no trace of 4-(2,4-dichlorophenoxy)-butyric acid was observed. These findings suggested that alkyl chain metabolism by the yeast follows a typical β-oxidation mechanism. The metabolism was partially inhibited by piperonylbutoxide, a common cytochrome P450 inhibitor. Dose-dependent production of 4-(2,4-dichlorophenoxy)-butyric acid from 1-butoxy-2,4-dichlorobenzene was evaluated. The maximum yield was 487 mg l −1 at 1 g l −1 of substrate. In summary, Y. lipolytica could efficiently produce 4-(2,4-dichlorophenoxy)-butyric acid from 1-alkoxy-2,4-dichlorobenzenesthrough oxidative metabolism. [ABSTRACT FROM AUTHOR]

Almost all oleaginous microorganisms are available for biodiesel production, and for the mechanism of oil accumulation, which is what makes a microbial approach economically competitive. This study investigated the potential that the yeast Candida lipolytica UCP0988, in an anamorphous state, has to produce simultaneously a bioemulsifier and to accumulate lipids using inexpensive and alternative substrates. Cultivation was carried out using waste soybean oil and corn steep liquor in accordance with 22 experimental designs with 1% inoculums (107 cells/mL). The bioemulsifier was produced in the cell-free metabolic liquid in the late exponential phase (96 h), at Assay 4 (corn steep liquor 5% and waste soybean oil 8%), with 6.704 UEA, IE24 of 96.66%, and showed an anionic profile. The emulsion formed consisted of compact small and stable droplets (size 0.2-5 μm), stable at all temperatures, at pH 2 and 4, and 2% salinity, and showed an ability to remove 93.74% of diesel oil from sand. The displacement oil (ODA) showed 45.34 cm2 of dispersion (central point of the factorial design). The biomass obtained from Assay 4 was able to accumulate lipids of 0.425 g/g biomass (corresponding to 42.5%), which consisted of Palmitic acid (28.4%), Stearic acid (7.7%), Oleic acid (42.8%), Linoleic acid (19.0%), and γ-Linolenic acid (2.1%). The results showed the ability of C. lipopytica to produce both bioemulsifier and biodiesel using the metabolic conversion of waste soybean oil and corn steep liquor, which are economic renewable sources. [ABSTRACT FROM AUTHOR]

Corn cob hydrolysate was used as substrate for growth and lipid accumulation via oleaginous yeast species. A mass based suspension of 10 g 100 g-1 corn cob hydrolysate contained 26.0 g L-1 glucose, 8.5 g L-1 xylose. The inhibitor concentrations were 0.16 g L-1 acetic acid, 1.50 g L-1 formic acid, 0.48 g L-1 HMF and 0.06 g L-1 furfural. These conditions reduced the cell growth of non-adapted yeast. Successful adaptation of the tested yeasts over several generations in corn cob hydrolysate was performed. The adapted yeast Candida lipolytica produced 19.4 g 100 g-1 lipids in relation to the dry weight in 7.5 g 100 g-1 dry matter corn cob hydrolysate in fed batch mode. The scale up was done up to a volume of 2.5 litres - here lipid accumulation up to 17.5 g 100 g-1 was demonstrated with the quantitative GC/FID analyses. Predominantly oleic acid, palmitic acid, linoleic and palmitoleic acid were produced. This lipid spectrum is suitable for biodiesel production. [ABSTRACT FROM AUTHOR]

We present the first clinical report of an infection caused by Candida galli, an anamorphic yeast species in the Yarrowia clade. C. galli has been described in the literature only four times, but never before it has been isolated from clinical samples. The colony morphology on Sabouraud medium and morphotype on CHROMagar Candida medium were similar to C. lipolytica as well as the carbon assimilation profile. The phenotypic differences with C. lipolytica were the non-assimilation of N-acetyl glucosamine, the absence of urease activity, growth in 10 % NaCl with 5 % glucose and in vitamin-free medium. MALDI-TOF MS could not generate reliable identification of the strain. Molecular analysis based on amplification of the ITS1-5.8S-ITS2 rDNA regions confirmed the identity as C. galli. Antifungal susceptibility test clearly demonstrated high MICs to 5-fluorocytosine, amphotericin B and fluconazole, as in the species belonging to the Yarrowia clade. [ABSTRACT FROM AUTHOR]

The maximisation of the production of metabolites of industrial interest from fermentative processes, such as biosurfactants, requires standardisation of the medium and the cultivation conditions. In this sense, experiments were conducted to maximise the production of the biosurfactant from Candida lipolytica UCP0988 cultivated on 5% animal fat and 2.5% corn steep liquor using a 2 3 full factorial design. The effects and interactions of the agitation speed (200, 300 and 400 rpm), the variables aeration (0, 1 and 2 vvm) and time of cultivation (48, 96 and 144 h) on the surface tension, yield and biomass were evaluated. The results showed that the variable time of cultivation had positive influence on the production of biosurfactant, while the increase of the variables aeration and agitation showed a negative effect. These results indicate that the biosurfactant has a strong potential to be applied as a clean-up of oil spills at sea and on shorelines. [ABSTRACT FROM AUTHOR]

Abstract: In this study, MgAl-LDHs (layered double hydroxides) intercalated with sodium dodecyl sulfate and outside surface modified with (3-aminopropyl)triethoxysilane (KH550) were prepared. The existence of organic part in LDHs improved immobilization efficiency and activity recovery of candida lipolytic lipase loaded. Also the positive charge in framework of LDHs was found to be beneficial to the enzyme immobilization. An immobilization efficiency of 56.4% and an activity recovery over 69.2% of the enzyme were obtained after it was loaded on the intercalated and modified LDHs, and catalytic activity of the immobilization can be kept at least five times. Moreover, the immobilized enzyme was found to have higher temperature resistance, wider pH value and better thermostability in reactive activity. [Copyright &y& Elsevier]

Abstract: There has been a growing interest in the use of biosurfactants to accelerate the transfer of hydrophobic contaminants and subsequent degradation by microbial cells. The aim of the present study was to investigate the applicability of a yeast biosurfactant, denominated Rufisan, which is reported to have excellent surfactant properties (Rufisan is capable of reducing surface tension of the medium to 25.29mN/m), in the treatment of contaminants from municipal solid waste contained in soils used as slurry barriers. Rufisan has been characterized as nontoxic and biodegradable. Soils with different granulometries were contaminated in the laboratory with motor oil. Oil removal tests were performed in beakers and packed glass columns. The results demonstrated that the crude Rufisan biosurfactant was able to remove approximately 30% of the motor oil from the soils in the static tests performed in glass columns, whereas the isolated biosurfactant at the critical micelle concentration removed 98% of the oil from beakers in the kinetic assays. Soil type and biosurfactant concentration exerted no influence on the oil removal rate, which suggests the displacement mechanism for the release of oil droplets adsorbed to the soil particles. The present findings demonstrate the potential of this biosurfactant as an adjuvant in environmental decontamination processes of petroleum derivates. [Copyright &y& Elsevier]

Abstract: In the present study, low-cost media based on animal fat and corn steep liquor combined with glucose, yeast extract, urea and other inorganic nitrogen sources were evaluated for the production of biosurfactants by the yeast Candida lipolytica UCP0988 in batch shake flasks. At the end of the 6-day fermentation period, the medium containing only animal fat (5%) and corn steep liquor (2.5%) yielded the maximal reduction in surface tension (from 50 to 28mN/m). The properties of the biosurfactant separated by different organic solvent extractions were investigated and the critical micelle concentration was determined. Preliminary chemical characterisation revealed the anionic nature of the biosurfactant. Compositional analysis of the biosurfactant was carried out using thin layer chromatography. The biosurfactant produced by the isolate was characterised as a glycolipid. Emulsification activity and surface tension stability of the biosurfactant produced using different hydrocarbons and vegetable oils and the effect of pH, temperature and the addition of salt were also studied. The cell-free broth (crude biosurfactant) was effective at recovering up to 70% of the residual oil from oil-saturated sand samples and also effective at oil displacement (54%). The crude biosurfactant from C. lipolytica and aqueous solutions of the isolated biosurfactant at 0.04%, 0.08% and 0.16% were effective in recovering up to 100% of the motor oil from the walls of the beakers. These properties indicate the potential of a cheaply produced glycolipid for application in the oil industry. [Copyright &y& Elsevier]

A series of macroporous beaded terpolymers with epoxy groups were synthesized by suspension polymerization with glycidyl methacrylate (GMA), ethylene glycol dimethacrylate (EGDMA), and the third monomers including styrene, methyl methacrylate, n-butyl acrylate (BA), butyl methacrylate (BMA), and 2-hydroxyethyl methacrylate for immobilization of Candida lipolytica lipase. The effect of various third monomers on loading and activity recovery of immobilized lipase were studied. Terpolymers with BA as the third monomer were found to give the biggest loading of lipase, and the activity recovery of lipase immobilized on poly(GMA-EGDMA-BA) terpolymers reached 79.0%. As the content of BA (%) increasing, the loading of lipase enhanced, but the activity recovery reached 88.5% for the initial stage and decreased to 46.9% at last. The poly(GMA-EGDMA-BA-10) showed an optimal result in lipase immobilization. Lipase immobilized on poly(GMA-EGDMA-BA-10) carriers had broader pH and higher temperature stability. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

Abstract: Rapid identification of clinically important yeasts can facilitate the initiation of anti-fungal therapy, since susceptibility is largely species-dependent. We evaluated melting peak and melting curve analysis of the internally transcribed spacer region 2 fragment (ITS2-MCA) as an identification tool for distinguishing between 16 Candida spp., i.e. Candida albicans, Candida bracarensis, Candida dubliniensis, Candida famata, Candida glabrata, Candida guilliermondii, Candida inconspicua, Candida kefyr, Candida krusei, Candida lipolytica, Candida lusitaniae, Candida nivariensis, Candida norvegensis, Candida parapsilosis, Candida tropicalis and Candida sojae, and Saccharomyces cerevisiae and one species pair, i.e. Candida metapsilosis/Candida orthopsilosis. Starting from a cultured isolate, ITS2-MCA led to differentiation of these species within 6 h. According to our findings, ITS2-MCA offers a simple, rapid and cost-effective method for identification of cultured isolates of the clinically most relevant and prevalent Candida species. Further studies will be necessary to evaluate how it performs on mixed samples and clinical samples. [Copyright &y& Elsevier]

Abstract: Sphingolipids are involved in cell differentiation and morphogenesis in eukaryotic cells. In this study, YlLac1p, a ceramide synthase required for glucosylceramide (GlcCer) synthesis, was found to be essential for hyphal growth in Yarrowia lipolytica. Y. lipolytica GlcCer was shown to be composed of a C16:0 fatty acid, which is hydroxylated at C2, and a C18:2 long chain base, which is unsaturated at both C4 and C8 and methylated at C9. Domain swapping analysis revealed that the entire TRAM/Lag1/CLN8 (TLC) domain, not the Lag1 motif, is crucial for the function of YlLac1p. YlDes1p, the C4 desaturase of the ceramide synthesized by YlLac1p, was also required for Y. lipolytica morphogenesis. Both Yllac1Δ and Yldes1Δ mutants neither polarize lipid rafts nor form normal vacuoles. Interestingly, mutation in YlPEX5, which encode a peroxisomal targeting signal receptor, partially suppressed the defective hyphal growth of Yllac1Δ. The Yllac1ΔYlpex5Δ mutant restored the ability to polarize lipid rafts and to form normal vacuoles, although it could not synthesize GlcCer. Taken together, our results suggest that GlcCer or GlcCer derivatives may be involved in hyphal morphogenesis in Y. lipolytica, at least in part, by affecting polarization of lipid rafts and vacuole morphogenesis. [Copyright &y& Elsevier]

The yeast Yarrowia lipolytica VKM Y-2412 was selected as a prospective producer of α-ketoglutaric acid (KGA) from ethanol. The following peculiarities were found: (1) the intensive KGA production occurred only under the limitation of cell growth by thiamine and the excess of ethanol and nitrogen, (2) the production of KGA from ethanol required increased amount of zinc and iron ions, and (3) KGA production increased significantly with a high aeration at pH medium equal to 3.5. Under optimal conditions, the Y. lipolytica VKM Y-2412 produced up to 172 g l of KGA with the mass yield coefficient of 0.70 g g. [ABSTRACT FROM AUTHOR]

Abstract: The inactivation of Candida lipolytica LMM02.68 and Escherichia coli LMM1010 on 1-cm apple cubes in acidified glucose solution (12.5 or 25.0% d-glucose) by high pressure treatment at 200–650MPa for 10min at 25 or 40°C was investigated. At 25°C and in all solutions, a 6-log reduction of C. lipolytica and E. coli was achieved at 400 and 600MPa, respectively. Subsequently the shelf-life of HP-treated packaged apple pieces in 25.0% acidified glucose solution was studied during refrigerated storage (7°C) in a pilot-scale study with 306 packages containing 200g of product. The microbiological shelf-life of the product, defined as the time when the aerobic mesophilic plate count or mold and yeast count first exceeded 7logCFU/g, was extended from 15days at 7°C for the untreated product to at least 90days after treatment at 450MPa at 10°C for 10min. HP treatment had no measurable effect on the hardness of the apple pieces, but to prevent browning during the entire storage period, addition of sodium metabisulfite was necessary. This work demonstrates that HP treatment is well suited to preserve fruit pieces in syrup for extended periods with maximal quality retention. Industrial relevance: HP-treated products are increasingly finding their way to the market. There is however a need of integrated studies that translate fundamental scientific findings from laboratory-scale model systems to the complexity and scale of real food production. In this study, the processing conditions required for the inactivation of relevant spoilage and pathogenic organisms by HP on apple pieces in glucose solution were defined. Subsequently, the shelf‐life was determined in a large scale pilot experiment comprising 306 packages each containing 200g of apple pieces in glucose solution, by evaluating both the microbiological quality and safety and color and texture during refrigerated storage after HP treatment. [Copyright &y& Elsevier]

We entrap lipase from Candida lipolytica by diatomite adsorption, and study the enzymatic properties of immobilized enzyme and free enzyme, we also use immobilized lipase for enzymatic wool scouring. The results show that the optimal temperature of the immobilized enzyme is increased 5 °C than free enzyme, and its optimum pH value mobiles to the alkaline direction by 0.5 units, with greatly improved thermal and pH value stability. Under the optimal reaction pH value of the immobilized enzyme, the optimal parameter of the variables are determined as:temperature 45 °C, bath ratio 1: 35 and time 20 h. [ABSTRACT FROM AUTHOR]

Abstract: This study aimed at enhancing α-ketoglutaric acid (α-KG) production by Yarrowia lipolytica WSH-Z06. Batch culture experiments demonstrated that CaCO3 and a relatively low pH (3.0) in the α-KG production phase contributed to α-KG synthesis. Using a two-stage pH control strategy, in which pH was buffered by CaCO3 in the growth phase and then maintained at 3.0 in the α-KG production phase, the yield of α-KG reached 53.4gL−1. In the later phase of batch fermentation, the glycerol was exhausted but synthesis of α-KG did not cease. Therefore, glycerol was fed with an integrated fed-batch mode, and α-KG production increased to 66.2gL−1 with a productivity of 0.35gL−1 h−1. Compared to optimal batch culture, α-KG production and productivity were enhanced by 23.9% and 16.7%, respectively. The two-stage pH control strategy, constant feeding approach and lower pH in later phase would be useful for α-KG industrial production. [Copyright &y& Elsevier]

The effects of agitation rates from 400 to 900 rpm and aeration rates ranging from 0.18 to 0.6 vvm on biomass and citric acid production on glycerol media by acetate-negative mutants of Yarrowia lipolytica, Wratislavia 1.31 and Wratislavia AWG7, in batch culture were studied. The agitation rates of 800 and 900 rpm (at a constant aeration rate of 0.36 vvm) and aeration rates within the range of 0.24–0.48 vvm (at a constant agitation rate of 800 rpm), which generated dissolved oxygen concentration (DO) higher than 40%, were found the best for citric acid biosynthesis from glycerol. An increase in agitation rate (higher than 800 rpm) and aeration rate (higher than 0.36 vvm) had no impact on DO and citric acid production. The highest citric acid concentration (92.8 g/L) and yield (0.63 g/g) were obtained with Wratislavia 1.31 strain at 0.24 vvm. The highest volumetric citric acid production rate (1.15 g/Lh) and specific citric acid production rate (0.071 g/gh) were reached at 0.48 vvm. [ABSTRACT FROM PUBLISHER]