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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.

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The stability of enzymes with no reduction in their catalytic activity still remains a critical issue in industrial applications. Naturally occurring osmolytes are commonly used as protein stabilizer. Apart from increasing the stability and catalytic activity, these osmolytes do not change the structure of enzyme. There are a few general schemes about the stabilization mechanism of these osmolytes but the details of their mechanism have not been found so far. In this study, we investigated the simultaneous effects of sorbitol and trehalose on the activity and structural stability of Pseudomonas cepacia lipase (PCL) using UV–visible, fluorescence and circular dichroism (CD) spectroscopy. In order to trace the refractive index and dielectric constant alterations upon the addition of osmolytes, microenvironment of the enzyme (PCL) was studied by means of SPR technique.The results revealed that osmolytes increased catalytic activity and intrinsic fluorescence intensity of PCL. In the presence of both osmolytes the activity of enzyme is greater than when each of the osmolytes is used individally. Far-UV CD spectra indicated that the secondary structural content of protein has been some what increased upon interacting with these osmolytes.The results of SPR technique indicated none of the above osmolytes could change the dielectric constant of medium considerably. This study revealed the synergy of two osmolytes toward increasing the activity and stability of enzyme.

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The effect of simultaneous application of probiotic and digestive enzyme on the intestinal digestive activity of the whiteleg shrimp, Litopenaeus vannamei, was evaluated. For this purpose, the juvenile shrimps were fed for 30 days with a dietary probio-enzyme (containing a combination of six exogenous enzymes and four probiotic bacterial strains) at four concentrations of 0, 0.25, 0.5, and 1 g kg^-1 feed. Shrimps (5.04±0.39 g ind^-1) were randomly distributed in 12 aquaria (4 treatments × 3 replications); each aquarium contained 15 individual shrimps. Results indicated significantly (p≤0.05) higher growth performance, amylase and lipase activity at 0.5 g kg^-1 treatment as compared to other treatments. Protease activity was, however, significantly (p≤ 0.05) higher at 1.0 g kg^-1treatment as compared to other groups. Results also indicated that increase in the concentration of probiotic and enzymes supplementation was not associated with increase in all the digestive enzyme activity. In other words, probiotics and enzymes onlywithin specific range can have positive effect on growth performance and digestive enzyme activity of L. vannamei, above or below.

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The present study investigateeffect of different dietary macronutrient composition on fatty acids profile, body fat and pancreatic lipase enzyme activity in Siberian sturgeon. A group of 180 Siberian sturgeons juvenile (initial weight, 30 ± 5 g) were used in this experiment and fed on four isoenergetic diets. Diets were named LP-St (low protein and high carbohydrate: lipid ratio), HP-St (high protein and high carbohydrate: lipid ratio), LP-L (low protein and low carbohydrate: lipid ratio) and HP-L (high protein and low carbohydrate: lipid ratio). Fish were fed apparent satiety for 10 weeks. The samples were obtained from body carcass and juveniles intestine. In this study, the same level of fish oil and sunflower oil were used as a source of diet lipid content. The HUFAs content in HP-St and LP-L diets were showed highest and lowest value, respectively. The results showed the body fatty acidsprofiles was significantly affected by fatty acids composition in diets (P < 0.5). Diets with high protein and high carbohydrates concentrated SFA and MUFA in fish carcass. Moreover, the PUFA content increased in sturgeon fed with high lipid diet. However,the results of this study showed the body lipid content wasaffected by total lipid content of diet and lipase activity decreased in Siberian sturgeon intestine fed on LP-L diet with lowest HUFA.

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Lipases, as an important enzyme group, are able to catalyze hydrolysis or synthesis of esters.The lipase from pseudomonas fluorescens (E.C.3.1.1.3) is a thermophilic kind of lipases (MW around 33 Kd). In this study, the effect of different concentrations of sorbitol on the activity and conformational stability of Psedomonas fluorescence lipase was evaluated using UV/Vis and Circular Dichroism (CD), respectively. According to the results of thermodynamic studies the 0.6 M concentration of sorbitol was selected for refolding and unfolding kinetic measurements with stopped flow fluorescence apparatus. Kinetics data indicate that unfolding of lipase is performed via two different pathways; one of them is probably involves a synchronous unfolding and dissociation of subunits and the other one comprises a two step unfolding in which the subunits are first dissociated followed by complete unfolding of subunits. We found that more population of protein molecules unfolded with slow phase unfolding pathway when sorbitol is present in the unfolding buffer. Furthermore; refolding kinetics data suggest that in the presence of sorbitol the energy barrier of refolding is reduced.

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From 1999 and 2000, DAG oil production has been started in Japan and USA. It must be mentioned that DAG oil has been considered as useful product for human health and it is known as functional and nutraceutical cooking oil. The objective of this study was to evaluate reaction parameters in DAG production from safflower oil and to optimize the process to obtain maximum yield of DAG. After safflower oil extraction, enzymatic glycerolysis was used to produce DAG oil. The treatments were determined using Design-expert software and after modeling, the process optimization was done. Finally, some physicochemical properties of DAG oil were investigated. After modeling, it was observed that the enzyme load had linear effect while the reaction temperature and glycerol content showed the quadratic effect on DAG yield. Also it was obtained that there was significant interaction effect between enzyme load/time, enzyme load/ glycerol and time/glycerol. Results showed that there was no significant difference between DAG and safflower oils in terms of specific gravity and iodine value but refractive index, color and peroxide value were different. Maximum production of DAG (48.454 %) obtained at reaction temperature of 46.9 ^ºC, reaction time of 4 h, enzyme load of 0.75 % (weight of oil), and molar ratio of glycerol to oil 2:1 which was increased to 53.84 % after product purification.  

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In recent years, following the mechanization of life, people tend to have products with higher quality and longer shelf life. Following this demand, studies have been introduced different technologies to the food industry; the part baked and frozen bread has been more attention. Although freezing, frozen storage and thawing have detrimental effect on bread properties. Use a variety breads improvement such as emulsifiers, oxidants and hydrocolloids can be used to reduce this impact without any negative effect. The aim of this study produce semi volume Barbari bread as part baked and frozen storage, in order to increase their shelf life and adding guar gum and lipase to formulation for improve quality, rheological and sensory characteristics in cycle freezing, storage and thawing. Bread prepared as part baked, freezing in -18ċ and storage for 15 day, after this time samples were thawing and full baked.  Then volume, porosity, texture, index image and sensory properties were measured. For Data Analysis used Statistica software and Duncan test, for mean comparisons. The result showed guar gum in 0.4 concentrations can be improvement volume, porosity, texture, index image and sensory properties, lipase at 0.05 level influenced on volume, porosity, texture in sensory properties and index image.  

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Nowadays, additives are commonly used in cooking industry. Emulsifiers are one of the important materials generally used to improve the quality and efficiency of dough, to make the usability of dough easier, and to reduce dough wastage through delaying the staling time. The purpose of this study is to investigate the influence of adding two kinds of emulsifier including DATEM and Glycerol mono stearate  In 3 levels of %0,% 0/2, and %0/4 and Lipase Enzyme in 3 levels of 0, 100, and 200 PPM(activity 25KLU/g). The influence of adding above-mentioned materials was sought in qualitative and quantitative features of doughnut made from solid dough (texture, moisture, activity water  (AW), specific volume, porosity, and general acceptability). According to the random statistical study and the obtained significant difference (p<0/05) among treatments, it was shown that the combinations with %0/2 of Datem, %0/2 of GMS and 100 PPM of Lipase Enzyme presented the most specific  volume, porosity, moisture and the least hardness level, and consequently low speed staling 2 hours after cooking and 4 days after maintenance. This instance won the highest grade from tasting judges. The result indicated that after the experiment the qualitative and quantitative features of doughnut improved in comparison with the instance case. The case with %0/2 of Datem, %0/2 of GMS and 100 PPM of Lipase Enzyme showed lower speed of staling. Other parameters such as moisture level, activity water (AW), volume, porosity level, and general acceptability also presented better condition in this case.  

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This study is aimed to investigate the effect of microbial Lipase enzymes in different concentration of 10,30 and 50 ppm and ckecking it effect on bugget`s quality. Physicochemical characteristics of bread such as moisture, volume, texture tough, color and intuitive traits are evaluated. The results revealed that there aren`t  any remarkable differences in smell, volume, taste, crust color, shape coordination, crack and rupture and exterior characteristics between experiments and control experiment in intuitive evaluation (P>0.5). Bread produced in 10,30 ppm values of  Lipase enzyme have more prominence  in  characteristics like inner texture , crust quality, improving the ability to br chewed, proper perforation of the texture than control experiment, but using 10 ppm Lipase showed the most prominence in receiving overall intuitive characteristics. According to the results of texture examinations, using10,30ppm concentrations lipase  is better than 50 ppm lipase. Bread produced with 10ppm lipase showed the maximum volume and best crumb color, and 30 ppm lipase enzyme the best crust color of the all, and it has the maximum moisture between experiments and it was a remarkable difference among all experiments (P<0.5).  

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Today, many studies are doing to identify the lipolytic microorganisms because of the important role of them in the production of microbial lipases. Oilseed meals are a good place to achieve these microorganisms. In this field, yeasts are more important in comparison with other microorganisms. In this study, we isolated 27 types of fungi from Yazd sesame meal. After the evaluation of macro and micro morphological features, it was identified that 16 of them were from yeast group. Lipolytic yeasts were screened using Tween 80 agar medium and were identified to genus and species by colony and cell morphology observations and evaluation of fermentation reactions and the use of carbon and nitrogen sources. 4 lipolytic  screened  yeasts were included Sporidiobolus pararoseus, Sporobolomyces salmonicolor, Cryptococcus albidus and Yarrowia lipolytica .The ratio of areola diameter to the well diameter was  between 2.314 – 2.714. S. pararoseus showed  the maximum ratio of areola to well diameter (2.714) .Lipase activity of these four types of yeasts was measured in submerged cultures with Cezepek Dox medium for 7 days at 30 °C and 200 rpm by using of photometry method and p-nitrophenyl palmitate substrate. Lipase activity range was between 0.866 – 4.333 U/ml, and Cryptococcus albidus had the highest lipase activity 4.333 U / ml, while it showed the least biomass growth among other yeasts (OD= 0.577). Yarrowia lipolytica showed lipase activity of 3.466 U/ml and also, the highest biomass growth OD =0.806.  

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Kimchi is a fermented herbal supplement, and appetizer that according to a raw material, process and geographical location are classified more than161 types. In this study, after kimchi production, isolation and identification of microorganisms was performed by molecular method. Lipase producing strain, Trichosporon asahii was isolated from kimchi sample (19.01 ±3 U/ml). The various medium components and culture parameters to achieve a more cost effective and economically viable bioprocess were screened and optimized using Design Expert software. PBdesignsare used to screen the most effective variables on lipase production that fermentation temperature and initial pHfor 48 hours 30 . According to the results, extract of nigella sativa, olive oil, yeast extract, magnesium chloride, respectively, were the most variable. Variable particle size and pepton ehavenegative effect. The variable selection and optimization on was performed more efficiently. Finally, lipase activity was 35 ± 0.5 U/ml in the optimal conditions using a medium containing15% sativa extract, 10 g/l yeast extract, 22.5 g/l olive oiland25 mM/l magnesium chloride in the rotation speed of 150 rpm, respectively, as well as enzyme activityafter84/1times the optimal state before optimization. The kinetic parameters V (max) and K (m) was 0.367 mM / min and 0.53 mM through Michaelis–Menten Chart, respectively. Low K_m indicates high affinity between enzyme and substrate and high V_max demonstrates high catalytic performance of the enzyme

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Yarrowia lipolytica is unusual yeast that has the ability to produce important metabolites such as lipase enzymes. Lipase enzyme has many applications in different industries including manufacturing of detergents, food industry, pharmacy, fuel and etc. In this paper, we studied the lipase enzyme produced by the yeast under different treatments of nitrogen sources such as yeast extract, peptone, soybean meal, sesame meal and sesame meal extracts on the medium of Czapek Dox Broth. Selected treatments of nitrogen resources include treatment solution (100%), solution (50%) containing with sesame cake extract (3.6%), solution (50%) containing with sesame cake extract (3.6%) in distilled water, solution (50%) containing with yeast extract (3.6%) in distilled water and solution (50%) containing with peptone (3.6%) in distilled water on the medium (CDB). Fermentation time levels are considered 3, 4 and 5 days. Among examined treatments, Treatment solution (50%) containing with sesame cake extract (3.6%) on the medium (CDB) showed the highest lipase activity (91.5900±0.56241 and 67.5200 ± 0.01000 enzyme units, respectively) in the fourth day of incubation with stirring speed (120 rpm) and temperature (30 °C). The results show use of sesame cake extract increases lipase activity more than use of yeast extract and peptone at the level of 5%. Also, statistical analysis of resulted data showed use of sesame cake extract increases lipase activity significantly at 5% level in comparison with yeast extract and peptone.

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The lipase is used broadly in different industries such as food, drug, petroleum and detergent industry due to the catalyst ability of wide range of conversion reactions such as hydrolyzed, esterification and transesterification . Yeasts are one of the main generators of lipases. In this paper, we use RSM and CCD in order to examine the effect of PH (5.5-7.5), time incubator (3-7days) and sesame meal extracts added to experimental medium (0-100%) on lipase generation and activity, generated biomass of Cryptococcus albidusand optimization of lipase generation process and generated biomass. The results showed that the percentages of sesame meal extracts added to experimental medium and time incubator are the most effective factors on lipase generation and activity and amount of generated biomass, respectively. Based on conducted experiments, optimized conditions of lipase generation and amount of generated biomass are determined PH 5.56 time incubator 7 days and percentages of sesame meal extracts added to experimental medium 100 percent in order to achieve maximum lipase activity (98.96 unit enzyme) and cell dry weight (1.14 gram per 100 mili liter medium).

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Researchers are currently directing their efforts toward developing new enzyme stabilization and enhancement strategies to broaden their application in various industries. This study utilized a unified platform to stabilize and safeguard proteins in industrial settings. Despite the wide-ranging industrial applications of lipases, their utility in industrial processes is limited by their susceptibility to degradation under harsh environmental conditions. In our study, we used a dual-purpose strategy that involved both enzyme stabilization and the shielding of an organosilica protective layer. After expressing and purifying the recombinant lipase enzyme, we immobilized it onto silica nanoparticles and shielded it with an organosilica nanolayer to protect the enzyme. We meticulously examined the optimal thickness of the protective layer and its influence on enzyme stabilization against environmental stressors. Our research findings demonstrate that the immobilized enzyme exhibited a remarkable level of stability compared to its free enzyme when subjected to various factors, such as fluctuations in temperature and exposure to chemical agents. Furthermore, the immobilized samples displayed optimal activity across a broad range of temperatures, highlighting this approach's adaptability and efficacy. Notably, the organosilica layer significantly bolstered the reactivity recovery of denatured proteins with SDS and urea, highlighting the versatile applications of this method. These findings indicated that our present platform has great potential to improve the efficiency and stability of industrial enzymes against various environmental challenges.
 

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Millet is one of the cereals that used in the preparation of gluten-free products for celiac patients. Physical modification methods such as heat-moisture treatments and microwave can be used to improve the performance of gluten-free flours in the baking industry. Millet seeds have limited shelf life in normal storage condition due to its relatively high fat content and high activity of lipase enzymes. In this study Heat-moisture treatments at different levels of moisture (11,15 and 20%) and two different temperatures (90 and 110°C) for 3 hours in oven and microwave treatment at different levels of moisture (11,15 and 20%) were used at different times (30,60 and 90S) with a constant power of 900 W. Then, in order to ensure the effect of the above treatments, the amount of free fatty acids of the treated flours was measured every 10 days as well as the level of lipase activity on the first day and after 30 days. In the heat-moisture treatment, the rate of inactivation of the lipase enzyme increased with simultaneous increase of moisture and temperature of the oven as well as in the microwave treatment with simultaneous increase of moisture and microwave time and the amount of free fatty acid flour during 30 days of storage was reduced. The highest rate of inactivation of lipase enzyme and the least change in the free fatty acid content of flour in heat-moisture and microwave treatments were observed in treatment with 20% moisture content and 110°C, and treatment with 20% moisture and 90S.

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Doogh is a dairy drink that has a special place among the drinks in the market. The two phases of this product during storage are a major problem due to the low pH and the accumulation of caseins.Therefore, in this study, the efficacy of microbial transglutaminase (at doses of 10, 15 and 20 ppm) and lipaseenzymes (at doses of 30, 45 and 60 ppm) in doogh stabilization and their effect on physicochemical, microbial, sensory and free fatty acids was investigated.To compare the mean of treatments, Duncan test was used at 5% probability level. Data analysis was done using SPSS software.
The results showed that treatment with these enzymes improved the stability.The amount of unsaturated fatty acids in the control sample is higher than the treated samples.The results of sensory evaluation showed no significant difference between treated and control samples (p> 0.05). But overall acceptance by evaluators increased with increasing dosages of enzymes in doogh.