scholarly journals Photo-hydrogen and lipid production from lactate, acetate, butyrate, and sugar manufacturing wastewater with an alternative nitrogen source byRhodobactersp.KKU-PS1

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6653 ◽  
Author(s):  
Thitirut Assawamongkholsiri ◽  
Alissara Reungsang ◽  
Sureewan Sittijunda

Photo-hydrogen and lipid production from individual synthetic volatile fatty acids (VFAs) and sugar manufacturing wastewater (SMW) byRhodobactersp. KKU-PS1 with sodium glutamate or Aji-L (i.e., waste from the process of crystallizing monosodium glutamate) as a nitrogen source was investigated. Using individual synthetic VFAs, the maximum hydrogen production was achieved with Aji-L as a nitrogen source rather than sodium glutamate. The maximum hydrogen production was 1,727, 754 and 1,353 mL H2/L, respectively, using 25 mM of lactate, 40 mM of acetate and 15mM of butyrate as substrates. Under these conditions, lipid was produced in the range of 10.6–16.9% (w/w). Subsequently, photo-hydrogen and lipid production from SMW using Aji-L as nitrogen source was conducted. Maximal hydrogen production and hydrogen yields of 1,672 mL H2/L and 1.92 mol H2/mol substrate, respectively, were obtained. Additionally, lipid content and lipid production of 21.3% (w/w) and 475 mg lipid/L were achieved. The analysis of the lipid and fatty acid components revealed that triacyglycerol (TAG) and C18:1 methyl ester were the main lipid and fatty acid components, respectively, found inRhodobactersp. KKU-PS1 cells.

RSC Advances ◽  
2015 ◽  
Vol 5 (94) ◽  
pp. 76779-76782 ◽  
Author(s):  
Hong-Yu Ren ◽  
Bing-Feng Liu ◽  
Fanying Kong ◽  
Lei Zhao ◽  
Nan-Qi Ren

Dark fermentative hydrogen production and microalgal lipid production was successfully combined to enhance the energy conversion from starch with simultaneous treatment of volatile fatty acids in the effluent.


Author(s):  
Ikumi Umetani ◽  
Eshetu Janka ◽  
Michal Sposób ◽  
Chris J. Hulatt ◽  
Synne Kleiven ◽  
...  

AbstractBicarbonate was evaluated as an alternative carbon source for a green microalga, Tetradesmus wisconsinensis, isolated from Lake Norsjø in Norway. Photosynthesis, growth, and lipid production were studied using four inorganic carbon regimes: (1) aeration only, (2) 20 mM NaHCO3, (3) 5% (v/v) CO2 gas, and (4) combination of 20 mM NaHCO3 and 5% CO2. Variable chlorophyll a fluorescence analysis revealed that the bicarbonate treatment supported effective photosynthesis, while the CO2 treatment led to inefficient photosynthetic activity with a PSII maximum quantum yield as low as 0.31. Conversely, bicarbonate and CO2 treatments gave similar biomass and fatty acid production. The maximum growth rate, the final cell dry weight, and total fatty acids under the bicarbonate-only treatment were 0.33 (± 0.06) day−1, 673 (± 124) mg L−1 and 75 (± 5) mg g−1 dry biomass, respectively. The most abundant fatty acid components were α-linolenic acid and polyunsaturated fatty acids constituting 69% of the total fatty acids. The fatty acid profile eventuated in unsuitable biodiesel fuel properties such as high degree of unsaturation and low cetane number; however, it would be relevant for food and feed applications. We concluded that bicarbonate could give healthy growth and comparative product yields as CO2.


2020 ◽  
Vol 42 (8) ◽  
pp. 1449-1455 ◽  
Author(s):  
Yongmei Zuo ◽  
Tassnapa Wongsnansilp ◽  
Xiaodong Zhang ◽  
Guiping Chen ◽  
Zhe Wu

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Ruiling Gao ◽  
Zifu Li ◽  
Xiaoqin Zhou ◽  
Wenjun Bao ◽  
Shikun Cheng ◽  
...  

Abstract Background Volatile fatty acids (VFAs) can be effective and promising alternate carbon sources for microbial lipid production by a few oleaginous yeasts. However, the severe inhibitory effect of high-content (> 10 g/L) VFAs on these yeasts has impeded the production of high lipid yields and their large-scale application. Slightly acidic conditions have been commonly adopted because they have been considered favorable to oleaginous yeast cultivation. However, the acidic pH environment further aggravates this inhibition because VFAs appear largely in an undissociated form under this condition. Alkaline conditions likely alleviate the severe inhibition of high-content VFAs by significantly increasing the dissociation degree of VFAs. This hypothesis should be verified through a systematic research. Results The combined effects of high acetic acid concentrations and alkaline conditions on VFA utilization, cell growth, and lipid accumulation of Yarrowia lipolytica were systematically investigated through batch cultures of Y. lipolytica by using high concentrations (30–110 g/L) of acetic acid as a carbon source at an initial pH ranging from 6 to 10. An initial pH of 8 was determined as optimal. The highest biomass and lipid production (37.14 and 10.11 g/L) were obtained with 70 g/L acetic acid, whereas cultures with > 70 g/L acetic acid had decreased biomass and lipid yield due to excessive anion accumulation. Feasibilities on high-content propionic acid, butyric acid, and mixed VFAs were compared and evaluated. Results indicated that YX/S and YL/S of cultures on butyric acid (0.570, 0.144) were comparable with those on acetic acid (0.578, 0.160) under alkaline conditions. The performance on propionic acid was much inferior to that on other acids. Mixed VFAs were more beneficial to fast adaptation and lipid production than single types of VFA. Furthermore, cultures on food waste (FW) and fruit and vegetable waste (FVW) fermentate were carried out and lipid production was effectively improved under this alkaline condition. The highest biomass and lipid production on FW fermentate reached 14.65 g/L (YX/S: 0.414) and 3.20 g/L (YL/S: 0.091) with a lipid content of 21.86%, respectively. By comparison, the highest biomass and lipid production on FVW fermentate were 11.84 g/L (YX/S: 0.534) and 3.08 g/L (YL/S: 0.139), respectively, with a lipid content of 26.02%. Conclusions This study assumed and verified that alkaline conditions (optimal pH 8) could effectively alleviate the lethal effect of high-content VFA on Y. lipolytica and significantly improve biomass and lipid production. These results could provide a new cultivation strategy to achieve simple utilizations of high-content VFAs and increase lipid production. Feasibilities on FW and FVW-derived VFAs were evaluated, and meaningful information was provided for practical applications.


1971 ◽  
Vol 17 (11) ◽  
pp. 1357-1365 ◽  
Author(s):  
E. A. Anderes ◽  
W. E. Sandine ◽  
P. R. Elliker

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.


1969 ◽  
Vol 20 (3) ◽  
pp. 491 ◽  
Author(s):  
GJ Faichney

Acetic, propionic, and butyric acids labelled with 14C were infused into the caecum of continuously fed sheep. The specific activity of the volatile fatty acids (VFA) in the caecum was determined at intervals during the infusion. The production rate was calculated by isotope dilution from the results of those experiments in which steady state conditions were obtained. Substantial interconversions occurred between the fatty acid fractions. The total production of VFA was about 440 mmoles/day, equivalent to 125 kcal/day or 5.3% of the animal's digestible energy intake.


1967 ◽  
Vol 18 (4) ◽  
pp. 625 ◽  
Author(s):  
FV Gray ◽  
RA Weller ◽  
AF Pilgrim ◽  
GB Jones

l(a). Volatile fatty acid (VFA) production (moles/12 hr) by two sheep fed at 2-hourly intervals on a constant ration containing equal parts of wheaten hay and lucerne hay, showed no significant difference between the sheep or between day-time and night-time values. The precision with which production could be measured over a series of 12-hr periods is given. The quantities of VFA produced in the rumen on successive days varied considerably; the extent of this variation was similar to that occurring in the quantities of faeces passed. (b) Production remained much the same whether the sheep were fed at intervals of 1, 2, or 12 hr. (c) The energy of the VFA produced in the rumen was equivalent to about 54% of the digestible energy of the diet. 2. Similar amounts of VFA were produced from two different mixtures of wheaten hay and lucerne hay, and from lucerne hay alone. 3. A modification in the procedure for measuring VFA production was tested and found to be satisfactory. The necessary apparatus could be readily carried on the back of a freely moving sheep.


2011 ◽  
Vol 102 (22) ◽  
pp. 10480-10485 ◽  
Author(s):  
Jingxian Sun ◽  
Xianzheng Yuan ◽  
Xiaoshuang Shi ◽  
Chunfeng Chu ◽  
Rongbo Guo ◽  
...  

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