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Feng Chen - One of the best experts on this subject based on the ideXlab platform.
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Isolation and proteomic alalysis of cell wall‐deficient Haematococcus pluvialis mutants
Proteomics, 2005Co-Authors: Sheng Bing Wang, Feng Chen, Milton R. SommerfeldAbstract:The green alga Haematococcus pluvialis has a plant-like cell wall consisting of glycoproteins and cellulose that is modified during the cell cycle and under various conditions. These features allow Haematococcus to be used as a model organism for studying cell wall biology. Development of the Haematococcus model is hampered by the absence of mutants that could provide insight into the biosynthesis and assembly of wall components. Haematococcus mutants (WM#537 and WM#2978) (WM--wall mutant) with defective cell walls were obtained by chemical mutagenesis. WM#537 features a secondary wall of considerably reduced thickness, whereas WM#2978 possesses a somewhat reduced secondary wall with little intervening space between the wall and plasmalemma. 2-DE revealed that a majority of the cell wall proteins were present in the wild-type and mutant cell walls throughout the cell cycle. PMF identified 55 wall protein orthologs from these strains, including a subset of induced proteins known to be involved in wall construction, remodeling, and defense. Down-regulation of certain wall proteins in the two mutants was associated with the wall defects, whereas overexpression of other proteins may have compensated for the defective walls in the two mutants.
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Purification of trans-astaxanthin from a high-yielding astaxanthin ester-producing strain of the microalga Haematococcus pluvialis
Food Chemistry, 2000Co-Authors: Jian-ping Yuan, Feng ChenAbstract:The purification method including extraction, saponification, and separation was established for preparing free trans-astaxanthin from a high-yielding astaxanthin ester-producing strain of the microalga Haematococcus pluvialis which contained 3.67% trans-astaxanthins and 1.35% cis-astaxanthins of the dry cells. Low temperature (5°C) was chosen to minimize the degradation of astaxanthins during saponification, and 94.4% free trans-astaxanthin was obtained from trans-astaxanthin esters after 12 h of saponification. With this method, 32.2 mg trans-astaxanthin was obtained from 1 g dry algal cells. In addition, a new gradient reversed-phase HPLC method, suited for the quick analysis of free astaxanthins and astaxanthin esters in the unsaponified and saponified pigment extracts from the high-yielding astaxanthin ester-producing strain of the microalga Haematococcus pluvialis, was developed and applied to the determination of astaxanthin contents during the processes of extraction, saponification, and purification.
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Chromatographic separation and purification of trans-astaxanthin from the extracts of Haematococcus pluvialis
Journal of Agricultural and Food Chemistry, 1998Co-Authors: Jian-ping Yuan, Feng ChenAbstract:A gradient reversed-phase HPLC method was developed for the separation of astaxanthin esters and the isomers of astaxanthin from the unsaponified and saponified pigment extracts of the microalga Haematococcus pluvialis. Four kinds of isomers of astaxanthin and astaxanthin esters, (3S,3‘S)-trans-astaxanthin, (3S,3‘S)-9-cis-astaxanthin, (3S,3‘S)-13-cis-astaxanthin, (3R,3‘R)-trans-astaxanthin, and their esters, were separated and identified. A small amount of (3S,3‘S)-15-cis-astaxanthin was also detected from the saponified extract. In addition, a chromatographic purification method was established for the preparation of natural trans-astaxanthin from the saponified extract of H. pluvialis. With this method, 3.7 mg of astaxanthin was isolated from 1 g of dry biomass of H. pluvialis. The purified astaxanthin contained approximately 97.7% trans-astaxanthin, 1.1% cis-astaxanthin, and 1.2% impurity. Keywords: Astaxanthin; astaxanthin esters; purification; carotenoids; Haematococcus pluvialis; HPLC
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Identification of astaxanthin isomers in Haematococcus lacustrisby HPLC-photodiode array detection
Biotechnology Techniques, 1997Co-Authors: Jian-ping Yuan, Feng ChenAbstract:An HPLC method was developed for the separation and identification of the isomers of astaxanthin from the saponification products of the individual astaxanthin ester fractions and the total pigment extract from Haematococcus lacus-tris. Six astaxanthin ester fractions were initially separated and collected by HPLC. These astaxanthin ester fractions and the total pigment extract were subsequently respectively hydrolysed. Four isomers of astaxanthin in the saponified mixtures were separated and identified respectively as (3S, 3¢S)- trans-astaxanthin (478.8 nm), (3S, 3¢S)-9-cis-astaxanthin (470.4 nm), (3S, 3¢S)-13- cis-astaxanthin (371.8 and 468.0 nm) and (3R, 3¢R)- trans-astaxanthin (477.6 nm) according to their absorbance spectra and absorption maxima by photodiode array detection. The relative contents of these isomers were determined to be 72.8, 9.7, 8.9 and 8.6%, respectively, in Haematococcus lacustris.
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Separation and identification of astaxanthin esters and chlorophylls in Haematococcus lacustris by HPLC
Biotechnology Techniques, 1996Co-Authors: Jian-ping Yuan, Xiandi Gong, Feng ChenAbstract:An isocratic reverse-phase high performance liquid chromatographic method was developed for the separation of carotenoids and chlorophylls from extracts of Haematococcus lacustris. Astaxanthin monoesters are the principal carotenoids in Haematococcus lacustris. Five astaxanthin monoesters, which accounted for 79% of the total carotenoids, were identified and the individual contents were determined by HPLC to be 7.3, 24.9, 6.1, 49.4 and 12.3% of the total astaxanthin monoesters, respectively. The maximum absorption wavelengths of the five astaxanthin monoesters in the mobile phase were all 479 nm, and that of free astaxanthin, the main saponification product of the astaxanthin esters, was 478 nm.
Milda Gumbyte - One of the best experts on this subject based on the ideXlab platform.
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Biomass and oil content of Chlorella sp., Haematococcus sp., Nannochloris sp. and Scenedesmus sp. under mixotrophic growth conditions in the presence of technical glycerol
Journal of Applied Phycology, 2014Co-Authors: Vaida Andruleviciute, Violeta Makareviciene, Virginija Skorupskaite, Milda GumbyteAbstract:The growth of algae strains Chlorella sp., Haematococcus sp., Nannochloris sp. and Scenedesmus sp. under mixotrophic conditions in the presence of different concentrations of technical glycerol was investigated with the aim of increasing biomass growth and algae oil content. The highest concentration of lipid obtained in media with 5 g L^−1 glycerol for Chlorella sp., Scenedesmus sp., Nannochloris sp. and Haematococcus sp. was 17.77, 22.34, 27.55 and 34.22 % larger than during the autotrophic growth of these species. Increases in triacylglycerols of up to ten times was observed for Scenedesmus sp. under mixotrophic conditions (using 10 g L^−1 glycerol), whereas an increase of 2.28 times was found for Haematococcus sp. The content of saturated fatty acids of Scenedesmus , Chlorella , Haematococcus and Nannochloris was 67.11, 34.63, 23.39 and 24.23 %, and the amount of unsaturated fatty acids was 32.9, 65.06, 79.61 and 75.78 % of total fatty acids, respectively. Growth on technical glycerol of these strains with light produced higher biomass concentrations and lipid content compared with autotrophic growth. The fatty acid content of oils from these species suggests their potential use as biodiesel feedstock.
Sang Jun Sim - One of the best experts on this subject based on the ideXlab platform.
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Enhanced astaxanthin extraction efficiency from Haematococcus pluvialis via the cyst germination in outdoor culture systems
Process Biochemistry, 2015Co-Authors: Yoon Young Choi, Min Eui Hong, Sang Jun SimAbstract:Abstract Haematococcus pluvialis is the richest source of natural astaxanthin (3S, 3′S), but the rigid cell wall of mature red cyst (aplanospore) complicates the efficient extraction of astaxanthin from the strain. Herein, the cyst germination method was developed by using nitrate and light for practical application for an efficient astaxanthin extraction from Haematococcus cells cultured in outdoor condition where flue gas, solar radiation and photobioreactor were used. Notably, autotrophic germination rate was easily regulated by light intensity. Under conditions of low germination rate, total astaxanthin concentration was highly maintained and astaxanthin extraction efficiency was rapidly enhanced during autotrophic germination. As a result, under homogenization (30 s), the extracted astaxanthin concentration in the cells treated with 1 mM KNO 3 –150 μE/m 2 /s was highly increased by 58% compared to the cells treated without germination. Our technical solution will definitely improve an astaxanthin extraction titer with the practical application in outdoor Haematococcus culture system.
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Astaxanthin production by a highly photosensitive Haematococcus mutant
Process Biochemistry, 2012Co-Authors: Min Eui Hong, Won Seok Chang, Seung Phill Choi, Youn-il Park, Young Kee Kim, Byung Woo Kim, Sang Jun SimAbstract:Abstract Haematococcus pluvialis synthesizes a high yield of astaxanthin using CO2 in a photoautotrophic culture without contaminant heterotrophs; however, it takes too long to induce astaxanthin production. In this study, a highly photosensitive mutant strain was attained by conventional random mutagenesis and an efficient isolation method to shorten induction time. Sensitivity to photoinhibition in this mutant was raised by a partial lesion in the photosystem II (PSII) of photosynthesis, thereby prompting a change in cellular morphology as well as stimulating carotenogenesis (astaxanthin production). As a result, the concentrations of cell biomass and astaxanthin were dramatically increased by 27% and 62% under strong light and 79% and 153% under moderate light, respectively. This Haematococcus mutant would be useful for the economical astaxanthin production capable of reducing the light energy cost in a photoautotrophic culture system, even in areas with insufficient sunlight.
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Productive Encystment of Haematococcus pluvialis by Controlling a Specific Irradiation Rate in a Photoautotrophic Induction System for Astaxanthin Production
Journal of Industrial and Engineering Chemistry, 2006Co-Authors: Chang Duk Kang, Jin Suk Lee, Tai Hyun Park, Sang Jun SimAbstract:A productive photoautotrophic induction system was established for the production of antioxidative astaxanthin by the green microalga Haematococcus pluvialis. During photoautotrophic induction, N-deprived Haematococcus cells were sensitive to the specific irradiation rate (I) on transformation to astaxanthin-rich cyst cells. Compared with the CO2 condition, the optimum specific irradiation rate (Iopt) was confined within narrow limits between light limitation and inhibition. Maximal astaxanthin synthesis in H. pluvialis was promoted under a 5 % CO2 environment and unsynchronized illumination with a specific irradiation rate of 80 µmol photon/g·s, yielding an accumulation rate of 4.3 mg/g·day. This result indicates that a favorable CO2 concentration and controlled specific irradiation rate leads to the productive encystment of H. pluvialis and enhanced astaxanthin synthesis.
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Astaxanthin biosynthesis from simultaneous N and P uptake by the green alga Haematococcus pluvialis in primary-treated wastewater
Biochemical Engineering Journal, 2006Co-Authors: Chang Duk Kang, Tai Hyun Park, Sang Jun SimAbstract:Abstract An alternative microalgal system for biological wastewater treatment is proposed for both the removal of nitrogen and phosphorus from wastewater and the production of a valuable carotenoid, astaxanthin. The system consists of sequential photoautotrophic cultivation and induction processes using the green alga Haematococcus pluvialis . The Haematococcus process was applied to primary-treated sewage (PTS) and primary-treated piggery wastewater (PTP) with serial dilution. H. pluvialis grew well on PTS and PTP diluted four-fold, resulting in the successful removal of nitrogen and phosphorus from both wastewaters. At that time, cell growth rates were comparable to those in the algal-defined NIES-C medium. Following the cultivation stage, N-deprived vegetative cells were transformed under photoautotrophic induction by continuous feeding of both CO 2 -mixed gas and intense light to red aplanospores with substantial astaxanthin contents. The resulting astaxanthin contents accounted for about 5.1 and 5.9% of the total biomass of the PTS and PTP cultures, respectively. Our results indicate the potential of the proposed Haematococcus process as a subsidiary wastewater treatment technology with the capability of biosynthesizing the high-value antioxidant astaxanthin.
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Comparison of heterotrophic and photoautotrophic induction on astaxanthin production by Haematococcus pluvialis
Applied microbiology and biotechnology, 2005Co-Authors: Chang Duk Kang, Tai Hyun Park, J. S. Lee, Sang Jun SimAbstract: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.
Jian-ping Yuan - One of the best experts on this subject based on the ideXlab platform.
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Purification of trans-astaxanthin from a high-yielding astaxanthin ester-producing strain of the microalga Haematococcus pluvialis
Food Chemistry, 2000Co-Authors: Jian-ping Yuan, Feng ChenAbstract:The purification method including extraction, saponification, and separation was established for preparing free trans-astaxanthin from a high-yielding astaxanthin ester-producing strain of the microalga Haematococcus pluvialis which contained 3.67% trans-astaxanthins and 1.35% cis-astaxanthins of the dry cells. Low temperature (5°C) was chosen to minimize the degradation of astaxanthins during saponification, and 94.4% free trans-astaxanthin was obtained from trans-astaxanthin esters after 12 h of saponification. With this method, 32.2 mg trans-astaxanthin was obtained from 1 g dry algal cells. In addition, a new gradient reversed-phase HPLC method, suited for the quick analysis of free astaxanthins and astaxanthin esters in the unsaponified and saponified pigment extracts from the high-yielding astaxanthin ester-producing strain of the microalga Haematococcus pluvialis, was developed and applied to the determination of astaxanthin contents during the processes of extraction, saponification, and purification.
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Chromatographic separation and purification of trans-astaxanthin from the extracts of Haematococcus pluvialis
Journal of Agricultural and Food Chemistry, 1998Co-Authors: Jian-ping Yuan, Feng ChenAbstract:A gradient reversed-phase HPLC method was developed for the separation of astaxanthin esters and the isomers of astaxanthin from the unsaponified and saponified pigment extracts of the microalga Haematococcus pluvialis. Four kinds of isomers of astaxanthin and astaxanthin esters, (3S,3‘S)-trans-astaxanthin, (3S,3‘S)-9-cis-astaxanthin, (3S,3‘S)-13-cis-astaxanthin, (3R,3‘R)-trans-astaxanthin, and their esters, were separated and identified. A small amount of (3S,3‘S)-15-cis-astaxanthin was also detected from the saponified extract. In addition, a chromatographic purification method was established for the preparation of natural trans-astaxanthin from the saponified extract of H. pluvialis. With this method, 3.7 mg of astaxanthin was isolated from 1 g of dry biomass of H. pluvialis. The purified astaxanthin contained approximately 97.7% trans-astaxanthin, 1.1% cis-astaxanthin, and 1.2% impurity. Keywords: Astaxanthin; astaxanthin esters; purification; carotenoids; Haematococcus pluvialis; HPLC
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Identification of astaxanthin isomers in Haematococcus lacustrisby HPLC-photodiode array detection
Biotechnology Techniques, 1997Co-Authors: Jian-ping Yuan, Feng ChenAbstract:An HPLC method was developed for the separation and identification of the isomers of astaxanthin from the saponification products of the individual astaxanthin ester fractions and the total pigment extract from Haematococcus lacus-tris. Six astaxanthin ester fractions were initially separated and collected by HPLC. These astaxanthin ester fractions and the total pigment extract were subsequently respectively hydrolysed. Four isomers of astaxanthin in the saponified mixtures were separated and identified respectively as (3S, 3¢S)- trans-astaxanthin (478.8 nm), (3S, 3¢S)-9-cis-astaxanthin (470.4 nm), (3S, 3¢S)-13- cis-astaxanthin (371.8 and 468.0 nm) and (3R, 3¢R)- trans-astaxanthin (477.6 nm) according to their absorbance spectra and absorption maxima by photodiode array detection. The relative contents of these isomers were determined to be 72.8, 9.7, 8.9 and 8.6%, respectively, in Haematococcus lacustris.
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Separation and identification of astaxanthin esters and chlorophylls in Haematococcus lacustris by HPLC
Biotechnology Techniques, 1996Co-Authors: Jian-ping Yuan, Xiandi Gong, Feng ChenAbstract:An isocratic reverse-phase high performance liquid chromatographic method was developed for the separation of carotenoids and chlorophylls from extracts of Haematococcus lacustris. Astaxanthin monoesters are the principal carotenoids in Haematococcus lacustris. Five astaxanthin monoesters, which accounted for 79% of the total carotenoids, were identified and the individual contents were determined by HPLC to be 7.3, 24.9, 6.1, 49.4 and 12.3% of the total astaxanthin monoesters, respectively. The maximum absorption wavelengths of the five astaxanthin monoesters in the mobile phase were all 479 nm, and that of free astaxanthin, the main saponification product of the astaxanthin esters, was 478 nm.
Vaida Andruleviciute - One of the best experts on this subject based on the ideXlab platform.
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Biomass and oil content of Chlorella sp., Haematococcus sp., Nannochloris sp. and Scenedesmus sp. under mixotrophic growth conditions in the presence of technical glycerol
Journal of Applied Phycology, 2014Co-Authors: Vaida Andruleviciute, Violeta Makareviciene, Virginija Skorupskaite, Milda GumbyteAbstract:The growth of algae strains Chlorella sp., Haematococcus sp., Nannochloris sp. and Scenedesmus sp. under mixotrophic conditions in the presence of different concentrations of technical glycerol was investigated with the aim of increasing biomass growth and algae oil content. The highest concentration of lipid obtained in media with 5 g L^−1 glycerol for Chlorella sp., Scenedesmus sp., Nannochloris sp. and Haematococcus sp. was 17.77, 22.34, 27.55 and 34.22 % larger than during the autotrophic growth of these species. Increases in triacylglycerols of up to ten times was observed for Scenedesmus sp. under mixotrophic conditions (using 10 g L^−1 glycerol), whereas an increase of 2.28 times was found for Haematococcus sp. The content of saturated fatty acids of Scenedesmus , Chlorella , Haematococcus and Nannochloris was 67.11, 34.63, 23.39 and 24.23 %, and the amount of unsaturated fatty acids was 32.9, 65.06, 79.61 and 75.78 % of total fatty acids, respectively. Growth on technical glycerol of these strains with light produced higher biomass concentrations and lipid content compared with autotrophic growth. The fatty acid content of oils from these species suggests their potential use as biodiesel feedstock.
