جستجوی مقالات مرتبط با کلیدواژه « یاروویا لیپولیتیکا » در نشریات گروه « علوم پایه »

Among the sources of oils (vegetable, animal, microorganism), microbial oil has attracted the attention of many researchers. Oily microorganisms are able to accumulate 20 to 80% of lipids in each dry biomass. Among various microorganisms (bacterias, microalgae, fungal species including yeasts), some yeasts are considered to be the superior source of oil production. Yarrowia lipolytica</em> is an excellent example of oily microorganisms with high fat production efficiency. By using cheap, native and available pulp as a production medium, the cost of oil produced by yeasts can be reduced. The microbial oil produced is used for medicinal, food and cosmetic purposes. In this study, the pleomorphism of Yarrowia lipolytica</em> (ATCC 18942) was examined microscopically in different culture media. After culturing the  yeast in media containing olive, sesame and sunflower pulp, in semi-open culture conditions, the fatty acids produced were analyzed using GC-MS and FTIR techniques. After reviewing the results, the medium containing olive pulp was selected and the microbial lipid produced in this medium was extracted. Then dry weight of biomass and microbial fat were measured. The results showed that the fatty acids extracted from the medium containing olive oli cake included oleic acid, palmitic acid, linoleic acid and stearic acid, which had the best production of fatty acids among the pulp. The content of  microbial fat and dry weight were 4.07 and 7.83 g/l, respectively, and microbial fat production efficiency was 51.97%. 

Glucose oxidase (GOX) is considered a commercial enzyme in the medicine, pharmaceutical, and food industries. Optimization of the fermentation medium and conditions is important to increase heterologous GOX production. The current study aimed to optimize GOX production in a ‎recombinant strain of Yarrowia lipolytica via statistical techniques.

Response surface methodology (RSM) as a statistical technique for the design of the experiment was used for the optimization of recombinant GOX production by Y. lipolytica. Then, the optimized conditions were used for the production of GOX in bioreactor cultivation.

GOX production was increased up to 570 U/L after optimization of the medium in flask culture which is 2 times more than the non-optimized medium. In the bioreactor culture using optimized medium containing glucose and sucrose as carbon sources, GOX production was reached 720 and 730 U/L after two and six days, respectively.

Results of the study provided valuable information about the statistical optimization of bioprocess development for the production of heterologous protein in Y. lipolytica.

Lipase (EC 3.1.1.3) is one of the most important class of industrial enzymes. The non-conventional yeast Yarrowia lipolytica is non-pathogenic to humans and is known as safe for some industrial processes. This yeast can produces different types of lipase. Extracellular lipase production depends on medium composition and environmental conditions. Olive oil as carbon source, yeast extract and tryptone as nitrogen sources and pH in different levels were investigated to optimization of lipase production in the mutant strain Yarrowia lipolytica FDY1390 by Taguchi experiment design method. Qualitek-4 software was used to Taguchi experiment design method. The highest lipase production (340 U/mL) was obtained in medium containing 20 g/L Olive oil, 15 g/L yeast extract and tryptone, pH 4 after 72 h of fermentation process. Study and optimization of lipase production can be reduce the cost of production and so use of this enzyme by various industries.

Proteases are the most important industrial enzymes. These enzymes have gained much attention due to their industrial applications in eliminating the environmental pollutions and improving the industrial processes. The aims of this research were the isolation and identification of native yeasts that were able to produce the alkaline protease. Several samples of soil, water and wastewater were collected from various places. The culture media used for screening of yeast spp. with potential of alkaline protease production were alkaline peptone agar and alkaline milk agar. The alkaline protease activity in potential spp. was measured using Lowry method. The effects of different culture media on the production of alkaline protease by selected yeast isolates were determined. For molecular identification of the best isolate, the DNA extraction was performed and the PCR followed using universal 18s rDNA primers. Among 27 isolates with the capability of alkaline protease production, one isolate with the most enzyme activity, 525 u/ ml, was selected for further processing. The best culture medium for alkaline protease production was YPG broth. The comparison of 18s rDNA sequence from isolated yeast with the highest enzyme activity, with the genomic database available in Gen Bank, using BLAST software showed that our yeast isolate had the highest similarity with Yarrowia lipolytica.Discussion and According to numerous applications of alkaline proteases industrially and the lack of their production in our country, the native strains could be beneficial for their production. Regarding to non-pathogenicity and high productivity of alkaline protease by our isolated yeast, Yarrowia lipolytica, this isolate could be introduced as an amenable strain for industrial production of alkaline protease.

Lipase is used in the production of detergents, cosmetics, pharmaceuticals, flavour enhancers and foods. The lipase of yeast Yarrowia lipolytica can be used for production of important class of chemical intermediates in the pharmaceutical industry. Lipase production depends on media composition and environmental conditions. Y. lipolytica DSM 3286 strain was cultured on media containing different organic and inorganic nitrogen sources. Lipase production was investigated by measuring biomass and lipase activity was detected by ρ-nitrophenyl laurate (PNPL) spectrophotometric assay method at various times within a period of 7 days. In this study, the effect of different nitrogen sources was investigated on Y. lipolytica DSM 3286 lipase production. The maximal lipase production (34.7 U/ml after 48 h) was detected in medium containing yeast extract as nitrogen source. The optimum temperature and pH of the enzyme activity were 37 °C and 7, respectively. The final goal of this study is to develop and optimize lipase production by Y. lipolytica for use in pharmaceutical industry.

The non-conventional yeast Yarrowia lipolytica produces several lipases. Lipase enzyme is one of the most important classes of industrial enzymes. Lipase is used in the production of detergents، cosmetics، pharmaceuticals، flavour enhancers and foods. Lipase production depends on media composition and environmental conditions. To select a suitable carbon source for high level of lipase production، Y. lipolytica DSM 3286 was cultured on different carbon sources. The highest lipase production was detected in medium containing Olive oil (34. 6 U/ml) after 48 h in comparison with other used carbon sources. The results of this study are under development Y. lipolytica lipase production.