Influence of Glucose and Saturated Free-Fatty Acid Mixtures on Citric Acid and Lipid Production by Yarrowia lipolytica

From a population of cells of Pseudomonas aeruginosa sensitive to 33 parts per million (ppm) of quaternary ammonium compound (QAC) and to 0.1 mg/ml of chloramphenicol (CAP), pure strains resistant to 750 ppm and 2.5 mg/ml of these antibacterial substances were isolated. Lipids from the sensitive and resistant cells grown under various conditions were extracted and characterized. Increased lipid biosynthesis was investigated as a possible factor in the resistance of this bacterium to CAP and QAC.Resistant cells grown in medium containing 207 ppm QAC at 25C averaged 77% more total lipid than sensitive cells. Resistant cells grown in the absence of QAC at 25C retained their resistance and averaged 27% more total lipid than sensitive cells. Cells grown at 32C in the presence of QAC contained 8% more total lipid than sensitive cells but less than cells grown at 25C under the same conditions. There was no increased lipid production by QAC-resistant cells grown at 37C in a Fermacell fermentor. Cells grown in CAP-containing medium (2.5 mg/ml) at 25C developed 28% more total lipid than sensitive cells grown in antibiotic-free medium.Gas–liquid chromatograms of the phospholipid, free fatty acid, and triglyceride fractions of the various cell types indicated that the same fatty acids were present. There was a 10% increase of the C18:1 fatty acid in both the phospholipid and free fatty acid fractions of the free lipids of cells grown in a Fermacell fermentor in the presence of CAP or QAC. However, there was no compensatory decrease in any single fatty acid, but rather a general decrease.Sensitive P. aeruginosa contained 14% free lipid and 3% to 6% bound lipid. The major phospholipid was phosphatidyl ethanolamine, which constituted 59% of the total phospholipid fraction of the sensitive cells. Analysis of fatty acids revealed that C16 amounted to 34%, C18:1 19%, and C16:1 and C18 each about 5% of the total present. These four fatty acids accounted for 63% of the free lipid present in the sensitive cells.

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Role of Enterococci in Cheddar Cheese: Free Fatty Acid Appearance and Citric Acid Utilization1

Journal of Milk and Food Technology ◽

10.4315/0022-2747-38.2.78 ◽

1975 ◽

Vol 38 (2) ◽

pp. 78-83 ◽

Cited By ~ 17

Author(s):

JANEP. JENSEN ◽

G. W. REINBOLD ◽

C. J. WASHAM ◽

E. R. VEDAMUTHU

Keyword(s):

Fatty Acid ◽

Citric Acid ◽

Free Fatty Acid ◽

Fatty Acid Content ◽

Cheddar Cheese ◽

Gas Production ◽

Lower Content ◽

Biochemical Effects ◽

Neutral Compounds

Eight lots of Cheddar cheese were manufactured to determine the microbiological response and biochemical effects of two strains each of Streptococcus faecalis and Streptococcus durans used as supplemental starters in combination with a commercial lactic culture. Each lot consisted of a control vat of cheese manufactured with the lactic starter only and an experimental vat of cheese containing the lactic starter and one of the enterococcus strains. Combinations of two curing temperatures (7.2 and 12.8 C) and two early cooling treatments (air vs. brine cooling) were used for cheeses from each vat to determine environmental effects on the cheeses. Cheeses manufactured with S. faecalis had a somewhat lower content of free fatty acids than did control cheeses, possibly because of early conversion of acids to neutral compounds. Cheeses manufactured with S. durans showed a fluctuating, but consistent, free fatty acid content among treatments, with overall amounts being greater than in the control cheeses or in cheeses made with S. faecalis. Cheeses cured at 12.8 C showed greater free fatty acid liberation, but the effects of early cooling rates were not significant. Citric acid in cheeses made with S. faecalis and in control cheeses was utilized most rapidly in 30 days at 12.8 C and extending to 60 days when cured at 7.2 C, after which no more breakdown seemed to occur. Cheeses made with S. durans 9–20 followed approximately the same pattern although some utilization took place between 90 and 180 days. In cheeses made with S. durans 15–20, however, citric acid utilization was continuous up to 180 days, and in cheeses cured at 12.8 C, citric acid was nearly depleted at 180 days. Cheeses made with S. durans 15–20 and cured at 12.8 C exhibited excessive gas production.

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Role of Enterococci in Cheddar Cheese: Organoleptic Considerations1

Journal of Milk and Food Technology ◽

10.4315/0022-2747-38.3.142 ◽

1975 ◽

Vol 38 (3) ◽

pp. 142-145 ◽

Cited By ~ 11

Author(s):

JANE P. JENSEN ◽

G. W. REINBOLD ◽

C. J. WASHAM ◽

E. R. VEDAMUTBU

Keyword(s):

Lactic Acid ◽

Fatty Acid ◽

Citric Acid ◽

Free Fatty Acid ◽

Cheddar Cheese ◽

Streptococcus Faecalis ◽

Growth And Survival ◽

Respective Control ◽

Significant Difference

Eight lots of Cheddar cheese were manufactured with two strains each of Streptococcus faecalis and Streptococcus durans and subjected to combinations of two early cooling treatments (air vs. brine cooling) and two curing temperatures (7.2 and 12.8 C). The enterococcus cultures were used as supplemental starters in combination with a commercial lactic culture. These cheeses were analyzed for microbiological growth and survival, proteolysis, lactic acid development, free fatty acid appearance, and citric acid utilization—each being compared with a control cheese made without enterococci. Results were presented in three previous articles. This series is concluded with the results of organoleptic ana1ysis of the cheeses. Cheeses made with S. faecalis were either comparable to or less desirable than their respective control cheeses. Those made with S. durans, however, were in all instances more desirable than their controls. Cheeses cured at 7.2 C were always given the better scores, but there was no statistically significant difference between air- and brine-cooled cheeses.

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Simultaneous Conversion of Triglyceride/Free Fatty Acid Mixtures into Biodiesel Using Sulfated Zirconia

Topics in Catalysis ◽

10.1007/s11244-010-9463-2 ◽

2010 ◽

Vol 53 (11-12) ◽

pp. 773-782 ◽

Cited By ~ 42

Author(s):

Dussadee Rattanaphra ◽

Adam Harvey ◽

Penjit Srinophakun

Keyword(s):

Fatty Acid ◽

Free Fatty Acid ◽

Sulfated Zirconia ◽

Fatty Acid Mixtures

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TRIANGULAR PHASE DIAGRAMS TO PREDICT THE FRACTIONATION OF FREE FATTY ACID MIXTURES VIA UREA COMPLEX FORMATION

Separation Science and Technology ◽

10.1081/ss-100000850 ◽

2001 ◽

Vol 36 (1) ◽

pp. 45-58 ◽

Cited By ~ 6

Author(s):

Douglas G. Hayes ◽

James Van Alstine ◽

Anne-Lee Asplund

Keyword(s):

Fatty Acid ◽

Free Fatty Acid ◽

Complex Formation ◽

Phase Diagrams ◽

Urea Complex ◽

Fatty Acid Mixtures

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THE EFFECT OF TEMPERATURE AND NITRATE COMPOUND ON GROWTH, BIOMASS AND FREE FATTY ACID CONTENT ON MICROALGAE CULTURE OF Spirulina sp. and Skeletonema sp.

Jurnal Bahan Alam Terbarukan ◽

10.15294/jbat.v7i1.8513 ◽

2018 ◽

Vol 7 (1) ◽

pp. 01-11

Author(s):

Nita Rukminasari ◽

Muhammad Lukman ◽

Rahmadi Tambaru ◽

Dwi Fajriyati Inaku ◽

Suharto Suharto

Keyword(s):

Growth Rate ◽

Fatty Acid ◽

Free Fatty Acid ◽

Acid Concentration ◽

Fatty Acid Content ◽

Lipid Production ◽

Fatty Acid Concentration ◽

Effect Of Temperature ◽

Free Fatty Acid Concentration ◽

Increasing Temperature

Temperature and availability nutrients played an important role on growth and lipid production of microalgae. In this study, we examined the effect of increasing suhu and excessed and depleted NO3 on growth rate, biomass and free fatty acid concentration in the Spirulina sp and Skeletonema sp. Two microalgae were culture on Conway and Milne media for 21 days using continuous culture technique. There were four temperature treatments, such as 28oC, 30oC, 32oC and 34oC and three nutrient treatments, which were control nutrient treatment, without NO3 and two times NO3 concentrations from control treatments with three replicates for each treatments. Results found that increasing temperature significantly affected on biomass and concentration free fatty acid, meanwhile nutrient treatments affected on growth rate, biomass and concentration of organic Carbon. In general, increasing temperature was more affected on Spirulina sp in terms of increasing growth rate, biomass and free fatty acid concentration. However, Skeletonema sp was more responsive to availability of NO3 in the media culture for increasing free fatty acid, and percentage of free fatty acid per dry weight.

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