scholarly journals GrowingChlorella vulgarisin Photobioreactor by Continuous Process Using Concentrated Desalination: Effect of Dilution Rate on Biochemical Composition

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Ângelo Paggi Matos ◽  
Regina Coeli de Oliveira Torres ◽  
Luiz Rodrigo Ito Morioka ◽  
Elisa Helena Siegel Moecke ◽  
Kepler Borges França ◽  
...  

Desalination wastewater, which contains large amount of salt waste, might lead to severely environmental pollution. This study evaluated the effect of dilution rate (0.1≤D≤0.3day−1) on microalgal biomass productivity, lipid content, and fatty acid profile under steady-state condition ofChlorella vulgarissupplemented with concentrated desalination. Continuous culture was conducted for 55 days. Results show that the biomass productivity (Px) varied from 57 to 126 mg L−1 d−1(dry mass) when the dilution rate ranged from 0.1 to 0.3 day−1. At lowest dilution rate (D=0.1day−1), the continuous culture regime ensured the highest values of maximum biomass concentration (Xm=570±20 mL−1) and protein content (52%). Biomass lipid content was an increasing function ofD. The most abundant fatty acids were the palmitic (25.3±0.6%) atD=0.1day−1and the gamma-linolenic acid (23.5±0.1%) atD=0.3day−1ones. These fatty acids present 14 to 18 carbons in the carbon chain, being mainly saturated and polyunsaturated, respectively. Overall, the results show that continuous culture is a powerful tool to investigate the cell growth kinetics and physiological behaviors of the algae growing on desalination wastewater.

Energies ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5975
Author(s):  
Małgorzata Hawrot-Paw ◽  
Adam Koniuszy ◽  
Małgorzata Gałczyńska

Microalgae are a renewable source of unconventional biomass with potential application in the production of various biofuels. The production of carbon-neutral fuels is necessary for protecting the environment. This work determined the possibility of producing biomass of microalgae belonging to Monoraphidium genus using saline wastewater resulting from proecological salmon farming in the recirculating aquaculture system. The tests were carried out in tubular photobioreactors using LED light. As a part of the analyses, the growth and productivity of microalgal biomass, cell density in culture, and lipid concentration and ash content in biomass were determined. In addition, the concentration of selected phosphorus and nitrogen forms present in wastewater corresponding to the degree of their use by microalgae as a nutrient substrate was determined. The biomass concentration estimated in the tests was 3.79 g·L−1, while the maximum biomass productivity was 0.46 g·L−1·d−1. The cells’ optical density in culture measured at 680 nm was 0.648. The lipid content in biomass was 18.53% (dry basis), and the ash content was 32.34%. It was found that microalgae of the genus Monoraphidium effectively used the nitrogen as well as phosphorus forms present in the wastewater for their growth. The total nitrogen content in the sewage decreased by 82.62%, and total phosphorus content by over 99%. The analysis of the individual forms of nitrogen showed that N-NO3 was reduced by 85.37% and N-NO2 by 78.43%, while orthophosphate (V) dissolved in water was reduced by 99%. However, the content of N-NH4 in wastewater from the beginning till the end of the experiment remained <0.05 mg·L−1.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Indu Ambat ◽  
Sabina Bec ◽  
Elina Peltomaa ◽  
Varsha Srivastava ◽  
Anne Ojala ◽  
...  

AbstractThe combination of wastewater treatment and biodiesel production using algal cultivation was studied in the present work. The two main goals of the work were achieved by the cultivation of freshwater microalgae such as Chlamydomonas sp., Scenedesmus ecornis, and Scenedesmus communis in two different dilutions of fertilizer plant wastewater (FWWD1 and FWWD2) collected from Yara Suomi Oy, Finland. The growth pattern of different algal species in FWWD1 and FWWD2 was observed. The effect of pH on biomass concentration, lipid content, biomass productivity, and lipid productivity by all three algal species in FWWD1 and FWWD2 were monitored. The maximum biomass concentration and productivity were observed in FWWD1 at pH7.5 for Chlamydomonas sp. and at pH 8.5 for S. ecornis and S. communis. The maximum lipid content was detected in Chlamydomonas sp at pH5.5, followed by S. ecornis and then S. communis at pH 7.5 in FWWD2 obtained after co-solvent extraction method. The most significant removal percentage of COD by all algal species were observed in FWWD1, whereas the highest removal percentage of TN and TP were detected in FWWD2, respectively. The fatty acid methyl ester (FAME) characterization of each algal species in FWWD1 and FWWD2 at their optimum pH was investigated to determine the quality of obtained biodiesel.


Water ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 106 ◽  
Author(s):  
Małgorzata Hawrot-Paw ◽  
Adam Koniuszy ◽  
Małgorzata Gałczyńska ◽  
Grzegorz Zając ◽  
Joanna Szyszlak-Bargłowicz

Aquaculture wastewater contains a huge amount of substances that can cause environmental pollution. However, microalgae can absorb these compounds and convert them into useful biomass. In this study, Chlorella minutissima was grown in the wastewater resulting from saline aquaculture. The microalgae were found to effectively utilize nitrogen and phosphorus in the wastewater for its growth. During wastewater treatment, the cell density increased almost fivefold compared to the initial value (OD680 0.502). Moreover, batch culture resulted in the maximum biomass concentration and productivity of 4.77 g/L and 0.55 g/L/day, respectively. The contents of total nitrogen and total phosphorus in wastewater decreased by 88% and over 99%, respectively. In addition, the content of N-NO3 was reduced by 88.6%, N-NO2 by 74.3%, and dissolved orthophosphates (V) by 99%. At the beginning and throughout the experiment, the content of N-NH4 in wastewater remained below 0.05 mg/L. Furthermore, a high lipid content of 46.4% (w/w) was also obtained from the studied microalgae.


Marine Drugs ◽  
2021 ◽  
Vol 19 (6) ◽  
pp. 314
Author(s):  
Won-Kyu Lee ◽  
Yong-Kyun Ryu ◽  
Woon-Yong Choi ◽  
Taeho Kim ◽  
Areumi Park ◽  
...  

There is increasing demand for essential fatty acids (EFAs) from non-fish sources such as microalgae, which are considered a renewable and sustainable biomass. The open raceway system (ORS) is an affordable system for microalgae biomass cultivation for industrial applications. However, seasonal variations in weather can affect biomass productivity and the quality of microalgal biomass. The aim of this study was to determine the feasibility of year-round Tetraselmis sp. cultivation in a semi-ORS in Korea for biomass and bioactive lipid production. To maximize biomass productivity of Tetraselmis sp., f medium was selected because it resulted in a significantly higher biomass productivity (1.64 ± 0.03 g/L) and lower omega-6/omega-3 ratio (0.52/1) under laboratory conditions than f/2 medium (0.70/1). Then, we used climatic data-based building information modeling technology to construct a pilot plant of six semi-ORSs for controlling culture conditions, each with a culture volume of 40,000 L. Over 1 year, there were no significant variations in monthly biomass productivity, fatty acid composition, or the omega-6/omega-3 ratio; however, the lipid content correlated significantly with photosynthetic photon flux density. During year-round cultivation from November 2014 to October 2017, areal productivity was gradually increased by increasing medium salinity and injecting CO2 gas into the culture medium. Productivity peaked at 44.01 g/m2/d in October 2017. Throughout the trials, there were no significant differences in average lipid content, which was 14.88 ± 1.26%, 14.73 ± 2.44%, 12.81 ± 2.82%, and 13.63 ± 3.42% in 2014, 2015, 2016, and 2017, respectively. Our results demonstrated that high biomass productivity and constant lipid content can be sustainably maintained under Korean climate conditions.


1961 ◽  
Vol 7 (4) ◽  
pp. 491-505 ◽  
Author(s):  
Andreas H. W. Hauschild ◽  
Hilliard Pivnick

An apparatus is described for the continuous growth of bacteria. Brucella abortus S.19 has been grown in continuous culture for periods up to 3 weeks with populations up to 2 × 1011viable cells per ml and without the establishment of nonsmooth variants.Concentrations between 3 × 109and 2 × 1011cells per ml could be maintained as a function of the dilution rate without the requirement of a known limiting factor in the medium. In a series of steady-state conditions, the specific growth rate increased steadily up to 0.28 hour−1with decreasing population levels.Incidence of mutants was governed by the dilution rate and could also be reduced by various chelating substances.In continuous growth combined with continuous dialysis, population levels were approximately twice those obtained in continuous growth without dialysis. The effect of dialysis appears to be the continuous removal of growth-limiting metabolic products.


1977 ◽  
Vol 8 (24) ◽  
pp. no-no
Author(s):  
J. C. JUN. CRAIG ◽  
M. F. KOZEMPEL ◽  
H. I. SINNAMON ◽  
M. J. CALHOUN ◽  
W. K. HEILAND

Plants ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 31 ◽  
Author(s):  
Maria N. Metsoviti ◽  
George Papapolymerou ◽  
Ioannis T. Karapanagiotidis ◽  
Nikolaos Katsoulas

In this research, the effect of solar irradiance on Chlorella vulgaris cultivated in open bioreactors under greenhouse conditions was investigated, as well as of ratio of light intensity in the 420–520 nm range to light in the 580–680 nm range (I420–520/I580–680) and of artificial irradiation provided by red and white LED lamps in a closed flat plate laboratory bioreactor on the growth rate and composition. The increase in solar irradiance led to faster growth rates (μexp) of C. vulgaris under both environmental conditions studied in the greenhouse (in June up to 0.33 d−1 and in September up to 0.29 d−1) and higher lipid content in microalgal biomass (in June up to 25.6% and in September up to 24.7%). In the experiments conducted in the closed bioreactor, as the ratio I420–520/I580–680 increased, the specific growth rate and the biomass, protein and lipid productivities increased as well. Additionally, the increase in light intensity with red and white LED lamps resulted in faster growth rates (the μexp increased up to 0.36 d−1) and higher lipid content (up to 22.2%), while the protein, fiber, ash and moisture content remained relatively constant. Overall, the trend in biomass, lipid, and protein productivities as a function of light intensity was similar in the two systems (greenhouse and bioreactor).


2017 ◽  
Vol 47 (2) ◽  
Author(s):  
Vitória Regina Takeuchi Fernandes ◽  
Maria Luiza Rodrigues de Souza ◽  
Eliane Gasparino ◽  
Marcos Eduardo Coutinho ◽  
Jesuí Vergílio Visentainer ◽  
...  

ABSTRACT: This study evaluated the yield, color, and chemical composition of commercial cuts (tail, sirloin cut, back fillet, and thigh) of Pantanal caiman meat in both sexes. The yield of tail was higher than other cuts, and the yield of females (17.0%) was higher than males (15.9%). The thigh of males had lower protein content (20.8%) compared with other cuts. Females showed a higher lipid content in the tail (2.4%) and thigh (0.8%) compared with males (1.7% and 0.4%, respectively). The tail presented the greatest content of monounsaturated fatty acids (45.2%) and higher n6/n3 ratio (4.6). Although lightness was not different among cuts or between sexes, there were differences in color. Males have more yellowish meat compared with females. Thigh and back fillet were more reddish when compared to sirloin cut and tail, regardless of sex. In conclusion, female tail meat provided greater yield and lipid content than males, and this result was statistically significant. These findings can help producers and consumers alike, better understand yield, quality, and nutritional quality of Pantanal caiman meat.


Plants ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 463 ◽  
Author(s):  
Ali Nawaz Kumbhar ◽  
Meilin He ◽  
Abdul Razzaque Rajper ◽  
Khalil Ahmed Memon ◽  
Muhammad Rizwan ◽  
...  

The decline in fossil fuel reserves has forced researchers to seek out alternatives to fossil fuels. Microalgae are considered to be a promising feedstock for sustainable biofuel production. Previous studies have shown that urea is an important nitrogen source for cell growth and the lipid production of microalgae. The present study investigated the effect of different concentrations of urea combined with kelp waste extract on the biomass and lipid content of Chlorella sorokiniana. The results revealed that the highest cell density, 20.36 × 107 cells−1, and maximal dry biomass, 1.70 g/L, were achieved in the presence of 0.5 g/L of urea combined with 8% kelp waste extract. Similarly, the maximum chlorophyll a, b and beta carotenoid were 10.36 mg/L, 7.05, and 3.01 mg/L, respectively. The highest quantity of carbohydrate content, 290.51 µg/mL, was achieved in the presence of 0.2 g/L of urea and 8% kelp waste extract. The highest fluorescence intensity, 40.05 × 107 cells−1, and maximum total lipid content (30%) were achieved in the presence of 0.1 g/L of urea and 8% kelp waste extract. The current study suggests that the combination of urea and kelp waste extract is the best strategy to enhance the biomass and lipid content in Chlorella sorokiniana.


1970 ◽  
Vol 45 (3) ◽  
pp. 313-324
Author(s):  
HC Schonfeldt ◽  
N Hall

Feeding systems, slaughter age and other production techniques notably influence the nutrient content of red meat. The modernization of the different South African production systems since the previous nutrient composition studies, justifies the necessity to update existing knowledge on the nutritional profile of South African produced beef. In addition, a need was identified to extrapolate the effect of the two different feeding systems (extensive and intensive) on this nutritional profile. Results indicate that the total lipid content of marketable young carcasses (age A, fat code 2) has decreased over time, in line with global health and nutrition trends for leaner foods. With the majority of beef from these young carcasses being produced on intensive grain-based feeding systems, South Africa has a unique advantage in terms of total lipid content of such grain-fed produce. Internationally, grain-fed red meat is in most cases higher in total and saturated fat content compared to grass-fed counterparts, while in South African the opposite was observed. In addition to total fat content, the role of various lipid fractions in human health has often been associated with specific produce positioning and marketing. South African grass-fed beef is significantly higher in healthy omega 3 fatty acids and conjugated linoleic acid, irrespective of degree of fat trimming. From a human nutrition perspective, it should be kept in mind that the total amount of omega 3 fatty acids per edible portion of beef produced in either production system is low in comparison to human dietary recommendations.Keywords: Beef, fatty acids, grain-fed beef, grass-fed beef, physical composition


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