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K Chekanov, E Schastnaya, A Solovchenko, E Lobakova
The atmospheric CO2 level is limiting for growth of phototrophic organisms such as microalgae, so CO2 enrichment boosts the growth and photosynthesis of microalgal cultures. Still, excessive CO2 injection might inhibit photosynthesis of microalgae. We investigated the effect of continuous sparging of the cultures of Haematococcus pluvialis BM 1 (IPPAS H-2018) (Chlorophyceae), the richest natural source of the value-added pigment astaxanthin. H. pluvialis cultures with CO2-enriched air-gas mixtures (with CO2 level from the atmospheric to 20%) on growth and astaxanthin accumulation in the microalga...
April 27, 2017: Journal of Photochemistry and Photobiology. B, Biology
Q L Luo, K P Wang, K Xiao, C G Wang, Z L Hu
Haematococcus pluvialis, as the most potential natural source of astaxanthin, which is a powerful antioxidant with high economic value, has attracted more and more scientific attention in recent years. An in-depth understanding of the mechanism for how H. pluvialis produces astaxanthin requires the intensive investigations on its genetic information. In particular, many reported studies were based on a variety of RNA analyses. However, it is difficult to extract RNA with high quality and quantity from H. pluvialis, because of the blockage from its thick cell wall and contamination by a large quantity of pigments, polysaccharides, and lipids...
April 13, 2017: Genetics and Molecular Research: GMR
Jieun Shin, Jong-Eun Kim, Kum-Ju Pak, Jung Il Kang, Tae-Seok Kim, Sang-Yoon Lee, Ik-Hyun Yeo, Jung Han Yoon Park, Jong Hun Kim, Nam Joo Kang, Ki Won Lee
Soybean-derived isoflavones have been investigated for their preventative effects against UV-induced symptoms of skin damage including wrinkle formation and inflammation. Haematococcus pluvialis is a freshwater species of Chlorophyta that contains high concentrations of the natural carotenoid pigment astaxanthin. Astaxanthin is known to be involved in retinoic acid receptor (RAR) signaling and previously been associated with the inhibition of activator protein (AP)-1 dependent transcription. Based on previous studies, we hypothesized that a combination of soy extract (SE) and Haematococcus extract (HE) may prevent UVB-induced photoaging through specific signaling pathways, as measured by UVB-induced wrinkling on hairless mice skin and expression changes in human dermal fibroblasts (HDFs)...
March 22, 2017: International Journal of Molecular Sciences
Han Sun, Bin Liu, Xue Lu, Ka-Wing Cheng, Feng Chen
An innovative staged cultivation (SC) method was proposed to overcome the limiting factors associated with the growth of Haematococcus pluvialis in the green growth phase. This strategy led to a 1.16-fold increase in biomass concentration. Light wavelength, nutrient concentration and extracellular metabolite were identified to be key limiting factors when cells of H. pluvialis were in the low, medium, and high cell density sub-phase, respectively. A mix of red and white light (2:1) was demonstrated for the first time to accelerate cell growth in the low cell density sub-phase...
March 4, 2017: Bioresource Technology
Ke Li, Jun Cheng, Hongxiang Lu, Weijuan Yang, Junhu Zhou, Kefa Cen
To elucidate the mechanism underlying the enhanced growth rate in the Haematococcus pluvialis mutated with (60)Co-γ rays and domesticated with 15% CO2, transcriptome sequencing was conducted to clarify the carbon metabolic pathways of mutant cells. The CO2 fixation rate of mutant cells increased to 2.57gL(-1)d(-1) under 15% CO2 due to the enhanced photosynthesis, carbon fixation, glycolysis pathways. The upregulation of PetH, ATPF0A and PetJ related to photosynthetic electron transport, ATP synthase and NADPH generation promoted the photosynthesis...
February 28, 2017: Bioresource Technology
Hui Jin, Yong Min Lao, Jin Zhou, Huai Jin Zhang, Zhong Hua Cai
A simple ultra-high-pressure liquid chromatography (UHPLC) method for rapidly and simultaneously identifying thirteen carotenoids in Haematococcus pluvialis was developed in this study. The method is capable of effectively separating two astaxanthin isomers, two ζ-carotene isomers, and three phytoene isomers on two simple C18 columns within 9 and 12min only by using methanol and acetonitrile, respectively. To our best knowledge, this is the rapidest method for these carotenoid isomers, currently. Using this method, carotenoid profiling in the astaxanthin-accumulating H...
March 10, 2017: Journal of Chromatography. A
Toshiyuki Komatsu, Suguru Sasaki, Yuki Manabe, Takashi Hirata, Tatsuya Sugawara
Astaxanthin, a carotenoid found mainly in seafood, has potential clinical applications due to its antioxidant activity. In this study, we evaluated the effect of dietary astaxanthin derived from Haematococcus pluvialis on skin photoaging in UVA-irradiated hairless mice by assessing various parameters of photoaging. After chronic ultraviolet A (UVA) exposure, a significant increase in transepidermal water loss (TEWL) and wrinkle formation in the dorsal skin caused by UVA was observed, and dietary astaxanthin significantly suppressed these photoaging features...
2017: PloS One
Jun Cheng, Ke Li, Yanxia Zhu, Weijuan Yang, Junhu Zhou, Kefa Cen
Transcriptome sequencing and annotation was performed on Haematococcus pluvialis mutant red cells induced with high light under 15% CO2 to demonstrate why astaxanthin yield of the mutant was 1.7 times higher than that of a wild strain. It was found that 56% of 1947 differentially expressed genes were upregulated in mutant cells. Most significant differences were found in unigenes related to photosynthesis, carotenoid biosynthesis and fatty acid biosynthesis pathways. The pyruvate kinase increased by 3.5-fold in mutant cells...
March 2017: Bioresource Technology
Lu-Lu Hou, Feng Liu, Xiaonan Zang, Xuecheng Zhang, Bangxiang He, Yating Ding, Xinwei Song, Dongfang Xiao, Haitao Wang
OBJECTIVES: To optimize the cultivation media for the growth rate of Haematococcus pluvialis and to study the transcription regulation of the algal nitrate reductase (NR), a key enzyme for nitrogen metabolism. RESULTS: The NR gene from H. pluvialis hd7 consists of 5636 nucleotides, including 14 introns. The cDNA ORF is 2718 bp, encoding a 905 aa protein with three conserved domains. The NR amino acids of H. pluvialis hd7 are hydrophilic and have similarity of 72% compared to that of Dunaliella...
April 2017: Biotechnology Letters
Litao Zhang, Fang Su, Chunhui Zhang, Fengying Gong, Jianguo Liu
The cell transformation from green motile cells to non-motile cells and astaxanthin accumulation can be induced in the green alga Haematococcus pluvialis cultured outdoors. In the initial 3 d of incubation (cell transformation phase), light absorption and photosynthetic electron transport became more efficient. After five days of incubation (astaxanthin accumulation phase), the light absorption per active reaction center (ABS/RC) increased, but the efficiency of electron transport (ψo) and the quantum yield of electron transport (φEo) decreased with increased time, indicating that the capacity of photosynthetic energy utilization decreased significantly during astaxanthin accumulation, leading to an imbalance between photosynthetic light absorption and energy utilization...
December 26, 2016: International Journal of Molecular Sciences
Yihong Zheng, Ze Li, Ming Tao, Jiancheng Li, Zhangli Hu
Algae are at a low trophic level and play a crucial role in aquatic food webs. They can uptake and accumulate the trace element selenium (Se), which can be either essential or toxic to algal growth depending on the dosage and species. Se toxicity and algae resistance varied across different organisms. In order to investigate the effects of Se on the unicellular green alga Haematococcus pluvialis, an important industrial resource for natural astaxanthin, the algal growth rate, chlorophyll content, and fluorescence parameters were derived from experimental treatment with different concentrations of selenite...
February 2017: Aquatic Toxicology
Martina Vakarelova, Francesca Zanoni, Piergiovanni Lardo, Giacomo Rossin, Federica Mainente, Roberto Chignola, Alessia Menin, Corrado Rizzi, Gianni Zoccatelli
Astaxanthin is a carotenoid known for its strong antioxidant and health-promoting characteristics, but it is also highly degradable and thus unsuited for several applications. We developed a sustainable method for the extraction and the production of stable astaxanthin microencapsulates. Nearly 2% astaxanthin was extracted by high-pressure homogenization of dried Haematococcus pluvialis cells in soybean oil. Astaxanthin-enriched oil was encapsulated in alginate and low-methoxyl pectin by Ca(2+)-mediated vibrating-nozzle extrusion technology...
April 15, 2017: Food Chemistry
Jan Jehlička, Adam Culka, Linda Nedbalová
We tested the potential of a miniaturized Raman spectrometer for use in field detection of snow algae pigments. A miniature Raman spectrometer, equipped with an excitation laser at 532 nm, allowed for the detection of carotenoids in cells of Chloromonas nivalis and Chlamydomonas nivalis at different stages of their life cycle. Astaxanthin, the major photoprotective pigment, was detected in algal blooms originating in snows at two alpine European sites that differed in altitude (Krkonoše Mts., Czech Republic, 1502 m a...
December 2016: Astrobiology
Adam Dawidziuk, Delfina Popiel, Magda Luboinska, Michal Grzebyk, Maciej Wisniewski, Grzegorz Koczyk
Due to its superior antioxidant capabilities and higher activity than other carotenoids, astaxanthin is used widely in the nutraceutical and medicine industries. The most prolific natural producer of astaxanthin is the unicellular green microalga Haematococcus pluvialis. The correct identification of any contaminants in H. pluvialis cultures is both essential and nontrivial for several reasons. Firstly, while it is possible to distinguish the main microalgal contaminant Coelastrella sp. (in H. pluvialis cultures), in practice, it is frequently a daunting and error-prone task for personnel without extensive experience in the microscopic identification of algal species...
May 2017: Journal of Applied Genetics
Yuan Guo, Yanping Dong, Xiao Hong, Xiaonan Pang, Defu Chen, Xiwen Chen
Identification and evolution of salt tolerant genes are crucial steps in developing salt tolerant crops or microorganisms using biotechnology. Ds-26-16, a salt tolerant gene that was isolated from Dunaliella salina, encodes a transcription factor that can confer salt tolerance to a number of organisms including Escherichia coli (E. coli), Haematococcus pluvialis and tobacco. To further improve its salt tolerance, a random mutagenesis library was constructed using deoxyinosine triphosphate-mediated error-prone PCR technology, and then screened using an E...
October 29, 2016: International Journal of Molecular Sciences
Xiaojuan Liu, Mingyue Song, Zili Gao, Xiaokun Cai, William Dixon, Xiaofeng Chen, Yong Cao, Hang Xiao
Astaxanthin (AST) is a xanthophyll carotenoid with potential protective effects against carcinogenesis. Different stereoisomers of AST (ASTs) exist in a variety of food sources. Due to limited information on the bioactivities of ASTs, the present study investigated the inhibitory effects of ASTs on HCT116 and HT29 human colon cancer cells. ASTs investigated herein included 3S,3'S (S) from Haematococcus pluvialis, 3R,3'R (R) from Phaffia rhodozyma, and a statistical mixture (S: meso: R = 1:2:1) (M) from synthetic AST...
October 11, 2016: Journal of Agricultural and Food Chemistry
Gianandrea Guidetti, Alessandro Di Cerbo, Angela Giovazzino, Valentina Rubino, Anna Teresa Palatucci, Sara Centenaro, Elena Fraccaroli, Laura Cortese, Maria Grazia Bonomo, Giuseppina Ruggiero, Sergio Canello, Giuseppe Terrazzano
Several extrinsic factors, like drugs and chemicals, can foster autoimmunity. Tetracyclines, in particular oxytetracycline (OTC), appear to correlate with the emergence of immune-mediated diseases. Accumulation of OTC, the elective drug for gastrointestinal and respiratory infectious disease treatment in broiler chickens, was reported in chicken edible tissues and could represent a potential risk for pets and humans that could assume this antibiotic as residue in meat or in meat-derived byproducts. We investigated the in vitro anti-inflammatory properties of a pool of thirteen botanicals as a part of a nutraceutical diet, with proven immunomodulatory activity...
2016: Journal of Immunology Research
Minmin Shang, Wei Ding, Yongteng Zhao, Jun-Wei Xu, Peng Zhao, Tao Li, Huixian Ma, Xuya Yu
Haematococcus pluvialis is a promising natural source of high-value antioxidant astaxanthin under stress conditions. Biotic or abiotic elicitors are effective strategies for improving astaxanthin production in H. pluvialis. Butylated hydroxyanisole (BHA) was identified as an effective inducer for H. pluvialis LUGU. Under a treatment of 2mgL(-1) BHA (BHA2), astaxanthin content reached a maximum of 29.03mgg(-1) dry weight (DW) (2.03-fold of that in the control) after 12day of the mid-exponential growth phase...
October 20, 2016: Journal of Biotechnology
Thi-Thao Vo, Changsu Lee, Sang-Il Han, Jee Young Kim, Sok Kim, Yoon-E Choi
In this study, we explored the effects of ACC on other stages of H. pluvialis. Interestingly, even though ACC displayed a dose-dependent effect on astaxanthin production, it is evident that astaxanthin production could be facilitated whenever the cells were treated at the early red stage. The transcriptional levels of BKT, CHY, SOD, and CAT genes supported enhanced astaxanthin biosynthesis upon ACC treatment at the early red stage. The combinatorial synergistic effect of ACC and light intensity was also confirmed...
November 2016: Bioresource Technology
Zhen Zhang, Baobei Wang, Qiang Hu, Milton Sommerfeld, Yuanguang Li, Danxiang Han
The unicellular green alga Haematococcus pluvialis has been exploited as a cell factory to produce the high-value antioxidant astaxanthin for over two decades, due to its superior ability to synthesize astaxanthin under adverse culture conditions. However, slow vegetative growth under favorable culture conditions and cell deterioration or death under stress conditions (e.g., high light, nitrogen starvation) has limited the astaxanthin production. In this study, a new paradigm that integrated heterotrophic cultivation, acclimation of heterotrophically grown cells to specific light/nutrient regimes, followed by induction of astaxanthin accumulation under photoautotrophic conditions was developed...
October 2016: Biotechnology and Bioengineering
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