Lipid metabolism and cell composition of the oleaginous yeast Apiotrichum curvatum grown at different carbon to nitrogen ratios

1990 ◽  
Vol 36 (5) ◽  
pp. 318-326 ◽  
Author(s):  
Wan-Soo Park ◽  
Patricia A. Murphy ◽  
Bonita A. Glatz
Keyword(s):  
Lipid Content ◽  
Lipid Accumulation ◽  
Catalase Activity ◽  
Oleaginous Yeast ◽  
Specific Activity ◽  
Dry Weight ◽  
Marker Enzyme ◽  
Cell Composition ◽  
Endogenous Lipid ◽  
Apiotrichum Curvatum

Apiotrichum curvatum ATCC 20509, an oleaginous yeast that can accumulate up to 60% of its cellular dry weight as intracellular lipid when grown with excess carbon, was grown in nitrogen-limited, balanced, and lactose-free medium with asparagine as nitrogen source and lactose as carbon source. Biomass and lipid accumulation were measured, cell composition was analyzed, and catalase activity was followed as marker enzyme for peroxisomes. The organism accumulated 54% of its dry weight as total cellular lipid when grown under nitrogen limitation and accumulated only 20–25% of its dry weight as lipid when grown in balanced medium. When starved for carbon, cells utilized endogenous lipid and carbohydrate as carbon and energy sources; the intracellular contents of lipid and carbohydrate decreased by 31 and 26%, respectively. Intracellular carbohydrates also seemed to be used as intermediates for lipid accumulation and lipid turnover. Catalase activity was strongly induced (over 10-fold increase in specific activity) when cells metabolized endogenous lipid. The lipid content of cells was inversely related to catalase activity and to intracellular protein or total nitrogen content. Lipid content showed no correlation with intracellular carbohydrate content. Key words: lipid, peroxisomes, oleaginous, Apiotrichum curvatum.

Evidence of peroxisomes and peroxisomal enzyme activities in the oleaginous yeast Apiotrichum curvatum

1991 ◽  
Vol 37 (5) ◽  
pp. 361-367 ◽  
Author(s):  
Wan Soo Park ◽  
Patricia A. Murphy ◽  
Bonita A. Glatz
Keyword(s):  
Enzyme Activities ◽  
Catalase Activity ◽  
Oleaginous Yeast ◽  
Corn Oil ◽  
Specific Activity ◽  
Glyoxylate Cycle ◽  
High Specific Activity ◽  
Beta Oxidation ◽  
Peroxisomal Enzyme ◽  
Apiotrichum Curvatum

The presence of peroxisomes and peroxisomal enzyme activities were investigated in the oleaginous yeast Apiotrichum curvatum ATCC 20509 (formerly Candida curvata D.) Catalase, a marker enzyme for peroxisomes, was measured in cell-free extracts prepared by sonication. The nature of the carbon and nitrogen sources in the growth medium greatly affected catalase activity. Cells grown on corn oil had high specific activity of catalase, but those grown on glucose, sucrose, or maltose had low specific activity. High specific activity of catalase was measured in cultures grown on media that supported poor growth (with soluble starch as carbon source or with methylamine, urea, or asparagine as nitrogen source). Peroxisomes from cells grown on corn oil were separated from other subcellular fractions in a discontinuous sucrose gradient. Major peaks of activity of fatty acid beta-oxidation and of two key enzymes in the glyoxylate cycle were found in fractions containing peroxisomes, but not in fractions corresponding to the mitochondria. Peroxisomal beta-oxidation showed equivalent activity with palmitoyl CoA or n-octanoyl CoA as substrate. Mitochondria did not seem to contain NAD-linked glutamate dehydrogenase. Peroxisomes with a homogeneous matrix and core surrounded by a single-layer membrane were observed with an electron microscope in cells grown on corn oil, but not in those grown on glucose. Staining with 3,3′-diaminobenzidine revealed that catalase activity was located in peroxisomes. Peroxisomes in this oleaginous yeast play important roles in lipid metabolism. Key words: lipid, peroxisomes, oleaginous, Apiotrichum curvatum, catalase, beta-oxidation, glyoxylate cycle.

scholarly journals Valorization of Brewers’ Spent Grain for the Production of Lipids by Oleaginous Yeast

Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3052 ◽  
Author(s):  
Alok Patel ◽  
Fabio Mikes ◽  
Saskja Bühler ◽  
Leonidas Matsakas
Keyword(s):  
Lipid Content ◽  
Oleaginous Yeast ◽  
Lipid Production ◽  
Enzymatic Saccharification ◽  
Dry Weight ◽  
Lipid Concentration ◽  
Microwave Assisted ◽  
Spent Grain ◽  
Synthetic Media ◽  
By Products

Brewers’ spent grain (BSG) accounts for 85% of the total amount of by-products generated by the brewing industries. BSG is a lignocellulosic biomass that is rich in proteins, lipids, minerals, and vitamins. In the present study, BSG was subjected to pretreatment by two different methods (microwave assisted alkaline pretreatment and organosolv) and was evaluated for the liberation of glucose and xylose during enzymatic saccharification trials. The highest amount of glucose (46.45 ± 1.43 g/L) and xylose (25.15 ± 1.36 g/L) were observed after enzymatic saccharification of the organosolv pretreated BSG. The glucose and xylose yield for the microwave assisted alkaline pretreated BSG were 34.86 ± 1.27 g/L and 16.54 ± 2.1 g/L, respectively. The hydrolysates from the organosolv pretreated BSG were used as substrate for the cultivation of the oleaginous yeast Rhodosporidium toruloides, aiming to produce microbial lipids. The yeast synthesized as high as 18.44 ± 0.96 g/L of cell dry weight and 10.41 ± 0.34 g/L lipids (lipid content of 56.45 ± 0.76%) when cultivated on BSG hydrolysate with a C/N ratio of 500. The cell dry weight, total lipid concentration and lipid content were higher compared to the results obtained when grown on synthetic media containing glucose, xylose or mixture of glucose and xylose. To the best of our knowledge, this is the first report using hydrolysates of organosolv pretreated BSG for the growth and lipid production of oleaginous yeast in literature. The lipid profile of this oleaginous yeast showed similar fatty acid contents to vegetable oils, which can result in good biodiesel properties of the produced biodiesel.

scholarly journals The Effect of Chromium on Photosynthesis and Lipid Accumulation in Two Chlorophyte Microalgae

2021 ◽  
Author(s):  
Khawaja Muhammad Imran Bashir ◽  
Hyeon-Jun Lee ◽  
Sana Mansoor ◽  
Alexander Jahn ◽  
Man-Gi Cho
Keyword(s):  
Lipid Content ◽  
Lipid Accumulation ◽  
Culture Medium ◽  
Dry Weight ◽  
Cell Number ◽  
Gravimetric Analysis ◽  
Growth Responses ◽  
Photosynthetic Inhibition ◽  
Negative Effect ◽  
The Impact

Heavy metals have adverse effects on microalgae growth and metabolism. Photosynthesis and lipid profile are quite sensitive to heavy metal toxicity. The impact of chromium (Cr) on growth and photosynthetic activity of Dictyosphaerium pulchellum and Micractinium pusillum exposed to different concentrations (0 – 500 μg L-1) was investigated for 11 days. The influence of Cr on cell density and cell number followed similar trends, indicating a possible correlation among these growth responses. A significant (p < 0.05) increase in lipid content was observed with the increasing concentration of Cr however, growth was suppressed at higher concentrations exceeding 100 μg L-1. Addition of Cr in the cell culture medium showed a negative effect on quantum yield (Fv/Fm) and a photosynthetic inhibition of > 65% was noted in both species at 500 μg L-1. However, the lipid gravimetric analysis presented inner cell lipid content up to 36% and 30% of dry weight biomass for D. pulchellum and M. pusillum, respectively. The effects of chromium on growth and lipid accumulation in both microalgae species was concentration and exposure time dependent. This shows that an appropriate concentration of chromium in culture medium could be beneficial for higher lipid accumulation in freshwater eukaryotic microalgae species.

scholarly journals Role of Snf-β in lipid accumulation in the high lipid‐producing fungus Mucor circinelloides WJ11

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Shaista Nosheen ◽  
Tahira Naz ◽  
Junhuan Yang ◽  
Syed Ammar Hussain ◽  
Abu Bakr Ahmad Fazili ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Lipid Metabolism ◽  
Lipid Content ◽  
Lipid Accumulation ◽  
Dry Weight ◽  
Mucor Circinelloides ◽  
Control Strain ◽  
High Lipid ◽  
Overexpressing Strain

Abstract Background Mucor circinelloides WJ11 is a high-lipid producing strain and an excellent producer of γ-linolenic acid (GLA) which is crucial for human health. We have previously identified genes that encode for AMP-activated protein kinase (AMPK) complex in M. circinelloides which is an important regulator for lipid accumulation. Comparative transcriptional analysis between the high and low lipid-producing strains of M. circinelloides showed a direct correlation in the transcriptional level of AMPK genes with lipid metabolism. Thus, the role of Snf-β, which encodes for β subunit of AMPK complex, in lipid accumulation of the WJ11 strain was evaluated in the present study. Results The results showed that lipid content of cell dry weight in Snf-β knockout strain was increased by 32 % (from 19 to 25 %). However, in Snf-β overexpressing strain, lipid content of cell dry weight was decreased about 25 % (from 19 to 14.2 %) compared to the control strain. Total fatty acid analysis revealed that the expression of the Snf-β gene did not significantly affect the fatty acid composition of the strains. However, GLA content in biomass was increased from 2.5 % in control strain to 3.3 % in Snf-β knockout strain due to increased lipid accumulation and decreased to 1.83 % in Snf-β overexpressing strain. AMPK is known to inactivate acetyl-CoA carboxylase (ACC) which catalyzes the rate-limiting step in lipid synthesis. Snf-β manipulation also altered the expression level of the ACC1 gene which may indicate that Snf-β control lipid metabolism by regulating ACC1 gene. Conclusions Our results suggested that Snf-β gene plays an important role in regulating lipid accumulation in M. circinelloides WJ11. Moreover, it will be interesting to evaluate the potential of other key subunits of AMPK related to lipid metabolism. Better insight can show us the way to manipulate these subunits effectively for upscaling the lipid production. Up to our knowledge, it is the first study to investigate the role of Snf-β in lipid accumulation in M. circinelloides.

Screening the Potential Oleaginous Yeast Strains for Lipid Accumulation on Glycerol, a By-Product from Biodiesel Production

2013 ◽  
Vol 781-784 ◽  
pp. 2445-2451
Author(s):  
Aksorn Riengsilchai ◽  
Pornpun Siramon ◽  
Vittaya Punsuvon
Keyword(s):  
Lipid Content ◽  
Lipid Accumulation ◽  
Oleaginous Yeast ◽  
Rhodotorula Glutinis ◽  
Biodiesel Production ◽  
Total Biomass ◽  
Glycerol Concentration ◽  
Cultivation Conditions ◽  
Inoculum Volume ◽  
Palm Oil Biodiesel

In this work, glycerol, a by-product from palm oil-biodiesel plant, was used as an alternative substrate for cultivating oleaginous yeast Rhodotorula glutinis (R. glutinis). Three R. glutinis strains were selected to compare the biomass production and lipid accumulation potencies namely, NBRC 0695, NBRC 1099 and NBRC 1501. The results found that R. glutinis NBRC 1099 was identified as the best lipid accumulation strain among the three strains tested, with a total biomass of 0.17 g/L and a lipid content of 40.80% at 24 hours when using the concentration of glycerol in the medium at 30 g/L. Furthermore, the optimization of cultivation conditions for the best oil producing strain obtained was evaluated using response surface methodology (RSM). A 5-level 2-factor central composite design (CCD) was used to build the statistical model. The optimum cultivation conditions for R. glutinis NBRC 1099 found in this study was: the glycerol concentration in the medium (34.14 g/L), the inoculum volume (1.6 mL; 4.5 x 107 cell) and incubated at 30°C for 24 hours. This optimum condition gave 43.65% of the lipid content. Five fatty acids were found in the lipid produced from this condition namely, myristic acid (0.72%), palmitic acid (19.64%), stearic acid (54.59%), oleic acid (19.44%), linoleic acid (2.04%) and linolenic acid (3.56%).

scholarly journals The Effect of Chromium on Photosynthesis and Lipid Accumulation in Two Chlorophyte Microalgae

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2260
Author(s):  
Khawaja Muhammad Imran Bashir ◽  
Hyeon-Jun Lee ◽  
Sana Mansoor ◽  
Alexander Jahn ◽  
Man-Gi Cho
Keyword(s):  
Fatty Acids ◽  
Lipid Content ◽  
Lipid Accumulation ◽  
Culture Medium ◽  
Dry Weight ◽  
Hexadecenoic Acid ◽  
Gravimetric Analysis ◽  
Photosynthetic Inhibition ◽  
Negative Effect ◽  
The Impact

Heavy metals have adverse effects on microalgae metabolism and growth. Photosynthesis and lipid profile are quite sensitive to heavy metal toxicity. The impact of hexavalent chromium—Cr(VI) on photosynthesis and lipid accumulation in Mucidosphaerium pulchellum and Micractinium pusillum exposed to different concentrations (0–500 μg L−1) was investigated for 11 days. A significant (p < 0.05) increase in lipid content was observed with increasing Cr(VI) concentration. However, growth was suppressed at higher concentrations exceeding 100 μg L−1. Addition of Cr(VI) in the cell culture medium showed a negative effect on quantum yield (Fv/Fm), and a photosynthetic inhibition of >65% was noted in both species at 500 μg L−1. However, the lipid gravimetric analysis presented inner cell lipid content up to 36% and 30% of dry weight biomass for M. pulchellum and M. pusillum, respectively. The fatty acids profiles of both microalgae species showed higher levels of hexadecenoic acid as well as ω3, ω6, and ω7 fatty acids. The effect of Cr(VI) on photosynthesis and lipid accumulation in both microalgae species was concentration and exposure time dependent. This shows that an appropriate concentration of Cr(VI) in culture medium could be beneficial for higher lipid accumulation in freshwater eukaryotic microalgae species.

Role of pentose phosphate pathway in lipid accumulation of oleaginous fungus Mucor circinelloides

RSC Advances ◽  
2015 ◽  
Vol 5 (118) ◽  
pp. 97658-97664 ◽  
Author(s):  
Lina Zhao ◽  
Xin Tang ◽  
Xiao Luan ◽  
Haiqin Chen ◽  
Yong Q. Chen ◽  
...  
Keyword(s):  
Lipid Content ◽  
Pentose Phosphate Pathway ◽  
Lipid Accumulation ◽  
Dry Weight ◽  
Mucor Circinelloides ◽  
Pentose Phosphate ◽  
Phosphogluconate Dehydrogenase ◽  
Oleaginous Fungus ◽  
Glucose 6 Phosphate Dehydrogenase

Overexpressing the genes coding for glucose 6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase from the pentose phosphate pathway in the oleaginous fungusMucor circinelloidesincreased the lipid content of cell dry weight by 20–30%.

BIOASSAY OF PROLACTIN

1969 ◽  
Vol 60 (1) ◽  
pp. 91-100 ◽  
Author(s):  
Charles S. Nicoll
Keyword(s):  
Epithelial Cells ◽  
Lipid Content ◽  
Dry Weight ◽  
Fat Content ◽  
Assay Sensitivity ◽  
Mucosal Epithelium ◽  
Wet Weight ◽  
Total Dry Weight

ABSTRACT The response of the pigeon crop-sac to systemically acting prolactin (injected subcutaneously) was evaluated by measuring the wet weight of the responsive lateral lobes of the organ and by determining the dry weight of a 4 cm diameter disc of mucosal epithelium taken from one hemicrop. Of several different injection schedules tested, administration of prolactin in four daily injections was found to yield optimal responses. When compared with a graded series of prolactin doses, measurement of the mucosal dry weight proved to be a better method of response quantification than determination of the crop-sac wet weight with respect to both assay sensitivity and precision. The submucosal tissue of the crop-sac was estimated to constitute about 64 % of the total dry weight of the unstimulated organ and it was found to be relatively unresponsive to prolactin stimulation in comparison with the mucosa. The lipid content of the mucosal epithelium was determined using unstimulated crop-sacs or tissues which showed varying degrees of prolactin-induced proliferation. The fat content of the mucosal epithelial cells increased only slightly more rapidly than the dry weight or the defatted dry weight of the mucosa. Suggestions are made for the further improvement of the systemic crop-sac assay for prolactin.

scholarly journals Field Cage Assessment of Feeding Damage by Riptortus pedestris on Soybeans in China

Insects ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 255
Author(s):  
Wenjing Li ◽  
Yu Gao ◽  
Yinglu Hu ◽  
Juhong Chen ◽  
Jinping Zhang ◽  
...  
Keyword(s):  
Lipid Content ◽  
Transfer Rate ◽  
Soybean Seed ◽  
Dry Weight ◽  
Nutrient Transfer ◽  
Field Cage ◽  
Stay Green ◽  
Riptortus Pedestris ◽  
Green Leaves ◽  
Pest Density

The bean bug, Riptortus pedestris, is a major pest of soybeans. In order to assess the critical stages of soybean damage by R. pedestris, we tested the damage to soybeans at different growth stages (R2, R4, and R6) caused by five densities of R. pedestris (1, 2, 3, 4, and 5) through a field cage experiment. The results show that the R4 stage was the most sensitive stage in terms of suffering R. pedestris injury damage, followed by the R6 stage and then the R2 stage. The number of stay green leaves was 7.04 per plant, the abortive pod rate of the soybeans was 56.36%, and the abortive seed rate of the soybeans was 46.69%. The dry weight of the soybeans was 14.20 g at the R4 stage; these values of R4 were significantly higher than at the R2 and R6 stages. However, the dry weight of soybean seed was 4.27 g and the nutrient transfer rate was 27.01% in the R4 stage; these values were significantly lower than in the R2 and R6 stages. The number of stay green leaves, abortive pod rates, and abortive seed rates were all increased significantly with increasing pest density at each stage of soybean growth. However, the nutrient transfer rate was significantly decreased with the increase in the pest density. Soybean nutrition factors changed after they suffered R. pedestris injury; the lipid content of the soybean seed decreased and the lipid content of the soybean plant increased compared to controls, when tested with a density of five R. pedestris in the R4 stage. These results will be beneficial to the future management of R. pedestris in soybean fields.

METHODS OF PROTEIN EXTRACTION FROM NEUROSPORA CRASSA

1964 ◽  
Vol 10 (1) ◽  
pp. 29-35 ◽  
Author(s):  
G. J. Stine ◽  
W. N. Strickland ◽  
R. W. Barratt
Keyword(s):  
Glutamic Acid ◽  
Neurospora Crassa ◽  
Total Protein ◽  
Extraction Method ◽  
Protein Extraction ◽  
Specific Activity ◽  
Dry Weight ◽  
Acid Dehydrogenase ◽  
Total Enzyme

Nine methods for disrupting the mycelium of Neurospora crassa have been compared. Protein percentages are calculated per gram dry weight of mycelium. A TPN-specific glutamic acid dehydrogenase was extracted and the efficiency of each extraction method is given as total enzyme extracted and specific activity. In terms of total protein, total enzyme, and practicality of the method, the Hughes Press, the French Press and the Raper–Hyatt Press were found to be the most efficient. The advantages and limitations of each method are considered.

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