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1.
A new paradigm for producing astaxanthin from the unicellular green alga Haematococcus pluvialis
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Zhen Zhang Baobei Wang Qiang Hu Milton Sommerfeld Yuanguang Li Danxiang Han 《Biotechnology and bioengineering》2016,113(10):2088-2099
2.
Kinetic models for astaxanthin production by high cell density mixotrophic culture of the microalga Haematococcus pluvialis 总被引:3,自引:0,他引:3
High cell density cultivation of Haematococcus pluvialis for astaxanthin production was carried out in batch and fed-batch modes in 3.7-L bioreactors with stepwise increased light
intensity control mode. A high cell density of 2.65 g L−1 (batch culture) or 2.74 g L−1 (fed-batch culture) was obtained, and total astaxanthin production in the fed-batch culture (64.36 mg L−1) was about 20.5% higher than in the batch culture (53.43 mg L−1). An unstructured kinetic model to describe the microalga culture system including cell growth, astaxanthin formation, as
well as sodium acetate consumption was proposed. Good agreement was found between the model predictions and experimental data.
The models demonstrated that the optimal light intensity for mixotrophic growth of H. pluvialis in batch or fed-batch cultures in a 3.7-L bioreactor was 90–360 μmol m−2 s−1, and that the stepwise increased light intensity mode could be replaced by a constant light intensity mode.
Received 24 December 1998/ Accepted in revised form 23 April 1999 相似文献
3.
Effects of hydrodynamic stress, dissolved oxygen (DO) concentration and carbon sources on heterotrophic α-tocopherol production
by Euglena gracilis were investigated. In a jar fermentor without baffle plates, increasing the agitation speed up to 500
rpm had no significant effect on cell growth and α-tocopherol production. However, in a jar fermentor equipped with baffle
plates, both the cell growth and α-tocopherol production were highly suppressed at 500 rpm. At high hydrodynamic stress, the
cells secreted nucleic acid-related substances to the culture broth and the shape of the cells shifted from elongated toward
spherical. High DO concentration had adverse effects on both cell growth and α-tocopherol production, the optimum DO concentration
being below 0.8 ppm. In comparison with glucose, the growth rate was lower but the α-tocopherol content of the cells was almost
four times higher when ethanol was used as the organic carbon source. In a fed-batch culture with ethanol, a very high cell
concentration of 39.5 g L-1 was obtained with α-tocopherol content of 1200 μg g-cell-1. This α-tocopherol content is very close to the values reported for photoautotrophic and photoheterotrophic cultures. A very
high α-tocopherol productivity of 102 μg L-1 h-1 was obtained, indicating that heterotrophic cultivation of E. gracilis has a very high potential as a substitute for the
current method of extraction from vegetable oils.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
4.
The green microalga Chlorella zofingiensis can produce the ketocarotenoid astaxanthin under heterotrophic culture conditions. Here we report the growth-associated biosynthesis
of astaxanthin in this biotechnologically important alga. With glucose as sole carbon and energy source, C. zofinginesis grew fast in the dark with rapid exhaustion of nitrogen and carbon sources from media, leading to a high specific growth
rate (0.034 h−1). Cultures started at a cell concentration of about 3.4 × 109 cells l−1 reached, after 6 days, standing biomass values of 1.6 × 1011 cells or 8.5 g dry weight l−1. Surprisingly, the biosynthesis of astaxanthin was found to start at early exponential phase, independent of cessation of
cell division. A general trend was observed that the culture conditions benefiting cell growth also benefited astaxanthin
accumulation, indicating that astaxanthin was a growth-associated product in this alga. The maximum cell dry biomass and astaxanthin
yield were 11.75 g l−1 and 11.14 mg l−1 (about 1 mg g−1), simultaneously obtained in the fed-batch culture with a combined glucose–nitrate mixture addition, which were the highest
ever reported in dark-heterotrophic algal cultures. The possible reasons why dark-heterotrophic C. zofingiensis could produce astaxanthin during the course of cell growth were discussed. 相似文献
5.
Jin Liu Zheng Sun Yujuang Zhong Henri Gerken Junchao Huang Feng Chen 《Journal of applied phycology》2013,25(5):1447-1456
The aim of the present study was to survey the growth and astaxanthin production of E17, an astaxanthin-rich mutant of Chlorella zofingiensis, through feeding the low-cost carbon source cane molasses. In heterotrophic batch cultivation, E17 fed with pretreated molasses achieved biomass (1.79 g L?1 day?1) and astaxanthin (1.99 mg L?1 day?1) productivities comparable to those with glucose, which were about 2- and 2.8-fold of those fed with untreated molasses, respectively. Molasses-induced astaxanthin accumulation may be attributed to the elicited expression of carotenogenic genes, in particular the genes specifically responsible for the ketolation and hydroxylation of β-carotene to form astaxanthin. A two-stage fed-batch strategy was employed to grow E17 and induce astaxathin accumulation, resulting in 45.6 g L?1 biomass and 56.1 mg L?1 astaxanthin, the highest volumetric astaxanthin yield ever reported for this alga. In addition, the astaxanthin production by E17 was tested with a semi-continuous culture method, where the directly diluted raw molasses (giving 5 g L?1 sugar) was used as the carbon source. Little growth inhibition of E17 was observed in the semi-continuous culture with a biomass productivity of 1.33 g L?1 day?1 and an astaxanthin productivity of 0.83 mg L?1 day?1. The mixotrophic semi-continuous cultures enhanced the biomass and astaxanthin productivities by 29.3 % and 42.2 %, respectively. This study highlights the potential of using the industrially cheap cane molasses towards large-scale cost-saving production of the high-value ketocarotenoid astaxanthin. 相似文献
6.
Influence of culture conditions such as light, temperature and C/N ratio was studied on growth of Haematococcus pluvialis and astaxanthin production. Light had significant effect on astaxanthin production and it varied with its intensity and direction
of illumination and effective culture ratio (ECR, volume of culture medium/volume of flask). A 6-fold increase in astaxanthin
production (37 mg/L) was achieved with 5.1468·107 erg·m−2·s−1 light intensity (high light, HL) at effective culture ratio of 0.13 compared to that at 0.52 ECR, while the difference in
the astaxanthin production was less than 2 — fold between the effective culture ratios at 1.6175·107 erg·m−2·s−1 light intensity (low light, LL). Multidirectional (three-directional) light illumination considerably enhanced the astaxanthin
production (4-fold) compared to unidirectional illumination. Cell count was high at low temperature (25 °C) while astaxanthin
content was high at 35 °C in both autotrophic and heterotrophic media. In a heterotrophic medium at low C/N ratio H. pluvialis growth was higher with prolonged vegetative phase, while high C/N ratio favoured early encystment and higher astaxanthin
formation. 相似文献
7.
Chang Duk Kang Se Jong Han Seung Phill Choi Sang Jun Sim 《Bioprocess and biosystems engineering》2010,33(1):133-139
A fed-batch culture process followed by subsequent photoautotrophic induction was established for the high density culture
of astaxanthin-rich Haematococcus pluvialis using a CO2-fed flat type photobioreactor under unsynchronized illumination. Fed-batch culture was performed with an exponential feeding
strategy of the growth-limiting nutrients, nitrate and phosphate, concurrently with the stepwise supplementation of light
depending on the cell concentration. During the growth phase, a biomass of 1.47 g/L was obtained at a biomass productivity
of 0.33 g/L/day. Photoautotrophic induction of the well-grown vegetative cells was performed consecutively by increasing the
light intensity to 400 μmol photon/m2/s, while keeping the other conditions in the CO2-fed flat type photobioreactor fixed, yielding an astaxanthin production of 190 mg/L at an astaxanthin productivity of 14 mg/L/day.
The proposed sequential photoautotrophic process has high potential as simple and productive process for the production of
valuable Haematococcus astaxanthin. 相似文献
8.
Comparison of heterotrophic and photoautotrophic induction on astaxanthin production by Haematococcus pluvialis 总被引:1,自引:0,他引:1
During light induction for astaxanthin formation in Haematococcus pluvialis, we substituted photoautotrophic induction for heterotrophic induction using acetate, both to prevent contamination by heterotrophs due to addition of organic carbon and to enhance carbon assimilation in the induced cells. Strong photoautotrophic induction was performed by N-deprivation of photoautotrophically grown Haematococcus cells followed by supplementation with bicarbonate (HCO3–) or CO2. Bicarbonate-induced cells contained more astaxanthin than acetate-induced cells, and even further enhancement of astaxanthin accumulation was achieved by continuous CO2 supply. The maximum astaxanthin content (77.2 mg g–1 biomass, 3.4-fold higher than with heterotrophic induction) was obtained under conditions of 5% CO2, yielding astaxanthin concentration and productivity of 175.7 mg l–1 and 6.25 mg l–1 day–1, respectively. The results indicate that photoautotrophic induction is more effective than heterotrophic induction for astaxanthin synthesis in H. pluvialis. 相似文献
9.
《Biochemical Engineering Journal》2008,40(3):575-580
Haematococcus pluvialis was cultivated under photoautotrophic conditions in a bubble column with fed-batch addition of nutrients, especially nitrate, and a cell number above 5 × 106 cells mL−1 was attained after 300 h.The reduction of nutrient concentrations accompanied by dilution of the fermentation broth and an increase in the light intensity enhanced accumulation of astaxanthin. The final astaxanthin concentration of 390 mg L−1 was several times higher than ever reported. This combination of fed-batch addition of nutrients and dilution of broth for nutrient deficiency is a promising method for attainment of high cell and astaxanthin concentrations in a bubble column photobioreactor. 相似文献
10.
S S Win A Impoolsup A Noomhorm 《Journal of industrial microbiology & biotechnology》1996,16(2):117-123
Growth kinetics ofSaccharomyces cerevisiae in glucose syrup from cassava starch and sugarcane molasses were studied using batch and fed-batch cultivation. The optimum temperature and pH required for growth were 30°C and pH 5.5, respectively. In batch culture the productivity and overall cell yield were 0.31 g L–1 h–1 and 0.23 g cells g–1 sugar, respectively, on glucose syrup and 0.22 g L–1 h–1 and 0.18 g cells g–1 sugar, respectively, on molasses. In fed-batch cultivation, a productivity of 3.12 g L–1 h–1 and an overall cell yield of 0.52 g cells g–1 sugar in glucose syrup cultivation and a productivity of 2.33 g L–1 h–1 and an overall cell yield of 0.46 g cells g–1 sugar were achieved in molasses cultivation by controlling the reducing sugar concentration at its optimum level obtained from the fermentation model. By using an on-line ethanol sensor combined with a porous Teflon® tubing method in automating the feeding of substrate in the fed-batch culture, a productivity of 2.15 g L–1 h–1 with a yield of 0.47 g cells g–1 sugar was achieved using glucose syrup as substrate when ethanol concentration was kept at a constant level by automatic control. 相似文献
11.
Joon Chul Park Seung Phill Choi Min-Eui Hong Sang Jun Sim 《Bioprocess and biosystems engineering》2014,37(10):2039-2047
For efficient astaxanthin production from the culture of green microalga, Haematococcus pluvialis, a two-stage mixotrophic culture system was established with stepwise increased light irradiance. By perfusion process, high density biomass (2.47 g/L) was achieved during the vegetative stage due to no detrimental effect of inhibitory metabolites, which was 3.09 and 1.67 times higher than batch and fed-batch processes, respectively. During the induction stage, biomass and astaxanthin were subsequently produced to the very high level 12.3 g/L and 602 mg/L, under stepwise increased light irradiance (150–450 μE/m2/s), respectively. These results indicate that the combinatorial approach of perfusion culture during the vegetative stage and stepwise light irradiation during the induction stage is a promising strategy for the simultaneous production of high concentration of biomass and astaxanthin in microalgae including H. pluvialis. 相似文献
12.
A low-cost nutrient medium based on corn steep liquor (CSL) was developed for the production of acetates byClostridium thermoaceticum. Pre-treatment of CSL with dolime and vitamin supplementation increased the rate of acetate production. Adding excess nutrients in a fed-batch mode minimized by-product formation and increased final acetate concentration from 19 g L–1 to 40 g L–1 acetic acid. High yields of acetic acid (0.95 g g–1 glucose in fed-batch mode) was probably due to the conversion of the lactic acid in CSL into acetic acid by the organism. 相似文献
13.
Gschaedler A. Thi Le N. Boudrant J. 《Journal of industrial microbiology & biotechnology》1994,13(4):225-232
Summary This study highlights data about the production of a recombinant protein (glyceraldehyde-3-phosphate dehydrogenase) byE. coli HB 101 (GAPDH) during batch and fed-batch fermentations in a complex medium. From a small number of experiments, this strain has been characterized in terms of protein production performance and glucose and acetate influences on growth and recombinant protein production. The present results show that this strain is suitable for recombinant protein production, in fed-batch culture 55 g L–1 of biomass and 6 g L–1 of GAPDH are obtained. However this strain, and especially GAPDH overproduction is sensitive to glucose availability. During fermentations, maximum yields of GAPDH production have been obtained in batch experiments for glucose concentration of 10 g L–1, and in fed-batch experiments for glucose availability of 10 g h–1 (initial volume 1.5 L). The growth of the strain and GAPDH overproduction are also inhibited by acetate. Moreover acetate has been noted as an activator of its own formation. 相似文献
14.
Induction of astaxanthin formation by reactive oxygen species in mixotrophic culture of Chlorococcum sp. 总被引:1,自引:0,他引:1
The induction of astaxanthin formation by reactive oxygen species in mixotrophic culture of Chlorococcum sp. was investigated. H2O2 (0.1 mM) enhanced the total astaxanthin formation from 5.8 to 6.5 mg g–1 cell dry wt. Fe2+ (0.5 mM) added to the medium with H2O2 (0.1 mM) further promoted astaxanthin formation to 7.1 mg g–1 cell dry wt. Similarly, Fe2+ (0.5 mM) together with methyl viologen (0.01 mM) promoted astaxanthin formation to 6.3 mg g–1 cell dry wt. In contrast, an addition of KI (1 mM), a specific scavenger for hydroxyl radicals (OH), together with H2O2 (0.1 mM) and Fe2+ (0.5 mM), to the medium decreased astaxanthin formation to 1.8 mg g–1 cell dry wt. KI (1 mM) also inhibited the enhancement of carotenogenesis by superoxide anion radicals (O2
–), with a decrease of astaxanthin formation to 1.7 mg g–1 cell dry wt. This suggested that O2
– might be transformed to OH before promoting carotenogenesis in Chlorococcum sp. 相似文献
15.
Production of biomass and phycocyanin (PC) were investigated in highly pigmented variants of the unicellular rhodophyte Galdieria sulphuraria, which maintained high specific pigment concentrations when grown heterotrophically in darkness. The parental culture, G. sulphuraria 074G was grown on solidified growth media, and intensely coloured colonies were isolated and grown in high-cell-density fed-batch
and continuous-flow cultures. These cultures contained 80–110 g L−1 biomass and 1.4–2.9 g L−1 PC. The volumetric PC production rates were 0.5–0.9 g L−1 day−1. The PC production rates were 11–21 times higher than previously reported for heterotrophic G. sulphuraria 074G grown on glucose and 20–287 times higher than found in phototrophic cultures of Spirulina platensis, the organism presently used for commercial production of PC. 相似文献
16.
M.M. Mendes-Pinto M.F.J. Raposo J. Bowen A.J. Young R. Morais 《Journal of applied phycology》2001,13(1):19-24
Although Haematococcus pluvialis is one of the most importantnatural sources of the carotenoid astaxanthin as a pigmentor for theaquaculture industry, the thick sporopollenin cell wall in the cysts hindersastaxanthin extraction and its subsequent bio-availability to fish. A rangeof physical and chemical processes were tested to promote the disruptionof the encysted cells. The efficacy of these processes was evaluated interms of astaxanthin recovery, which was assessed by determining theextent of leaching of astaxanthin into an organic solvent. The processestested were: autoclave 30 min, 121 °C, 1 atm; HCl 0.1 M, 15min and 30 min; NaOH 0.1 M, 15 min and 30 min; enzymatictreatment with a mixture of 0.1% protease K and 0.5% driselase in aphosphate buffer, pH 5.8, 30 °C, for one hour; spray drying, inlet180 °C, outlet 115 °C; and mechanical disruption, with acell homogeniser developed for this purpose. The mechanical(homogenisation) and autoclave treatments were the most effective in termsof extraction and availability. 相似文献
17.
Factors affecting the astaxanthin production by a unicellular green alga, Haematococcus pluvialis UTEX 16, were evaluated with sequential fractional factorial design. To simulate an actual production mode, a two-stage process was adapted for astaxanthin production: the alga was first cultivated under vegetative growth conditions, and then astaxanthin production was induced by applying various induction methods. A high dose of irradiation was most effective for the production of astaxanthin both in weight (mg/g) and in cellular (pg/cell) contents. A combination of nitrogen deficiency and acetate addition also significantly increased the astaxanthin content of cells on a dry weight basis. Meanwhile, the acetate addition alone increased only the cellular content of astaxanthin. Although the addition of ferrous ion alone had a negative effect on the weight content of astaxanthin, simultaneous addition of ferrous ion and acetate was effective for increasing the cellular content of astaxanthin. 相似文献
18.
The green alga Haematococcus pluvialis is the current best source of natural astaxanthin, a high-value carotenoid. Traditionally, the production process of astaxanthin by this algae is achieved by a two-stage system: during the first stage, vegetative “green” cells are produced and then converted, in the second stage, into cysts that accumulate astaxanthin. In this work, a medium screening strategy based on the mixing of a three-component hydroponic fertilizer was applied to identify a new formulation optimized for the vegetative stage. A maximal and high cell density of 2?×?106 cells mL?1 was obtained in a medium containing a high level of phosphate relative to nitrate, resulting in a N/P ratio much lower than commonly used media for H. pluvialis. In this medium, cells remained at the vegetative and motile stage during a prolonged period of time. Both high cell density culture and motile stage persistence was proved to be related to the N/P feature of this medium. We conclude that the macrozoid stage of H. pluvialis is favored under high-P and low-N supply and that low-cost hydroponic fertilizers can be successfully used for achieving high density cultures of vegetative cells of H. pluvialis. 相似文献
19.
Luis M. Lubián Olimpio Montero Ignacio Moreno-Garrido I. Emma Huertas Cristina Sobrino Manuel González-del Valle Griselda Parés 《Journal of applied phycology》2000,12(3-5):249-255
Pigment composition and its variation with culture agewere analyzed in six strains of Nannochloropsis(Eustigmatophyceae). The capacity for accumulationof the ketocarotenoids astaxanthin and canthaxanthinwas higher in N. salina and N. gaditanathan in the other strains studied here. Theinfluence of salinity (15 to 100 practical units) onpigment production was studied in N. gaditana,where a defined pattern of variation could not befound apart from a notable increase in zeaxanthin at100. In cultures grown in a photobioreactor and athigh cell densities of about 109 cells mL-1,pigment production reached: 350 mg L-1 forchlorophyll a, 50 mg L-1 for violaxanthin,5 mg L-1 for canthaxanthin, 3 mg L-1 forastaxanthin. The highest contents of canthaxanthin andastaxanthin obtained in experiments with N.gaditana were 19.4 and 14.6 ng pigment (106cells)-1, respectively, which accounts for 0.7%dry weight. By means of xanthophyll cycle inductionthrough exposure of cells to high irradiance and at40 °C, conversion of violaxanthin intozeaxanthin may attain up to 70% of the violaxanthincontent, which corresponds to 0.6% dry weight. Theresults indicate that interest in Nannochloropsis as a source of valuable pigments isnot related to its capacity for single pigmentaccumulation, but the availability of a range ofpigments such as chlorophyll a, zeaxanthin,canthaxanthin and astaxanthin, each with highproduction levels. 相似文献
20.
A family of 10 competing, unstructured models has been developed to model cell growth, substrate consumption, and product formation of the pyruvate producing strain Escherichia coli YYC202 ldhA::Kan strain used in fed-batch processes. The strain is completely blocked in its ability to convert pyruvate into acetyl-CoA or acetate (using glucose as the carbon source) resulting in an acetate auxotrophy during growth in glucose minimal medium. Parameter estimation was carried out using data from fed-batch fermentation performed at constant glucose feed rates of
qVG=10 mL h–1. Acetate was fed according to the previously developed feeding strategy. While the model identification was realized by least-square fit, the model discrimination was based on the model selection criterion (MSC). The validation of model parameters was performed applying data from two different fed-batch experiments with glucose feed rate
qVG=20 and 30 mL h–1, respectively. Consequently, the most suitable model was identified that reflected the pyruvate and biomass curves adequately by considering a pyruvate inhibited growth (Jerusalimsky approach) and pyruvate inhibited product formation (described by modified Luedeking–Piret/Levenspiel term).List of symbols cA
acetate concentration (g L–1)
- cA,0
acetate concentration in the feed (g L–1)
- cG
glucose concentration (g L–1)
- cG,0
glucose concentration in the feed (g L–1)
- cP
pyruvate concentration (g L–1)
- cP,max
critical pyruvate concentration above which reaction cannot proceed (g L–1)
- cX
biomass concentration (g L–1)
- KI
inhibition constant for pyruvate production (g L–1)
- KIA
inhibition constant for biomass growth on acetate (g L–1)
- KP
saturation constant for pyruvate production (g L–1)
- KP
inhibition constant of Jerusalimsky (g L–1)
- KSA
Monod growth constant for acetate (g L–1)
- KSG
Monod growth constant for glucose (g L–1)
- mA
maintenance coefficient for growth on acetate (g g–1 h–1)
- mG
maintenance coefficient for growth on glucose (g g–1 h–1)
- n
constant of extended Monod kinetics (Levenspiel) (–)
- qV
volumetric flow rate (L h–1)
- qVA
volumetric flow rate of acetate (L h–1)
- qVG
volumetric flow rate of glucose (L h–1)
- rA
specific rate of acetate consumption (g g–1 h–1)
- rG
specific rate of glucose consumption (g g–1 h–1)
- rP
specific rate of pyruvate production (g g–1 h–1)
- rP,max
maximum specific rate of pyruvate production (g g–1 h–1)
- t
time (h)
- V
reaction (broth) volume (L)
- YP/G
yield coefficient pyruvate from glucose (g g–1)
- YX/A
yield coefficient biomass from acetate (g g–1)
- YX/A,max
maximum yield coefficient biomass from acetate (g g–1)
- YX/G
yield coefficient biomass from glucose (g g–1)
- YX/G,max
maximum yield coefficient biomass from glucose (g g–1)
-
growth associated product formation coefficient (g g–1)
-
non-growth associated product formation coefficient (g g–1 h–1)
-
specific growth rate (h–1)
- max
maximum specific growth rate (h–1) 相似文献