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Bahareh Nahidian, Faezeh Ghanati, Maryam Shahbazi, Neda Soltani
The vegetative growth of Haematococcus pluvialis TMU1 was studied under batchwise cultivation in three common media, namely BBM, BG11, and 3NBBM. The BBM provided the best condition for the algal growth. It was further studied at different levels of nitrate and phosphate as macronutrients as well as iron and boron as trace elements. The dose-response of the algal growth to these macro/micronutrients was modeled with Monod/hormetic-type kinetics. Applying the modified BBM with 3-fold higher phosphate led to the highest cell density and up to 86% increase in the growth rate...
January 31, 2018: Bioresource Technology
Ranga Rao Ambati, Deepika Gogisetty, Ravishankar Gokare Aswathanarayana, Sarada Ravi, Panduranga Narasimharao Bikkina, Lei Bo, Su Yuepeng
Microalgae are rich source of various bioactive molecules such as carotenoids, lipids, fatty acids, hydrocarbons, proteins, carbohydrates, amino acids, etc. and in recent year's carotenoids from algae gained commercial recognition in the global market for food and cosmeceutical applications. However, the production of carotenoids from algae is not yet fully cost effective to compete with synthetic ones. In this context the present review examines the technologies/methods in relation to mass production of algae, cell harvesting for extraction of carotenoids, optimizing extraction methods etc...
January 25, 2018: Critical Reviews in Food Science and Nutrition
Pandian SureshKumar, Jibu Thomas, Vasudevan Poornima
Research on bioremediation of polycyclic aromatic hydrocarbons (PAHs) has established that several remediating microbial species are capable of degrading only low molecular weight (LMW)-PAHs, whereas high molecular weight (HMW)-PAHs are hardly degradable. In the present study, the efficiency of degradation of both LMW and HMW-PAHs by cytochrome P450 monooxygenase (CYP) of microalgae was studied. CYP have a key role in the detoxification of xenobiotics. So far, the structure of CYP in microalgae is not predicted; the protein structure was constructed by molecular modelling in the current study using the available template of microalgal CYP...
January 22, 2018: Environmental Monitoring and Assessment
Bangxiang He, Lulu Hou, Manman Dong, Jiawei Shi, Xiaoyun Huang, Yating Ding, Xiaomei Cong, Feng Zhang, Xuecheng Zhang, Xiaonan Zang
Haematococcus pluvialis is a commercial microalga, that produces abundant levels of astaxanthin under stress conditions. Acetate and Fe2+ are reported to be important for astaxanthin accumulation in H. pluvialis. In order to study the synergistic effects of high light stress and these two factors, we obtained transcriptomes for four groups: high light irradiation (HL), addition of 25 mM acetate under high light (HA), addition of 20 μM Fe2+ under high light (HF) and normal green growing cells (HG). Among the total clean reads of the four groups, 156,992 unigenes were found, of which 48...
January 7, 2018: International Journal of Molecular Sciences
Thomas O Butler, Gordon J McDougall, Raymond Campbell, Michele S Stanley, John G Day
Astaxanthin from Haematococcus pluvialis is commercially produced in a two-stage process, involving green vegetative (macrozooid) and red aplanospore stages. This approach has been scaled up to an industrial process but constraints limit its commercial success and profitability, including: contamination issues, high pigment extraction costs, requirements for high light levels and photo-bleaching in the red stage. However, in addition to the aplanospore stage, this alga can produce astaxanthin in vegetative palmelloid and motile macrozooid cells...
December 26, 2017: Biology
Ruijuan Ma, Skye R Thomas-Hall, Elvis T Chua, Faisal Alsenani, Eladl Eltanahy, Michael E Netzel, Gabriele Netzel, Yinghua Lu, Peer M Schenk
Haematococcus pluvialis is a green microalga of major interest to industry based on its ability to produce large amounts of astaxanthin. Biosynthesis of astaxanthin and its mono- and di-esters was significantly stimulated under 150 μmol m-2 s-1 of white LED (W-150) compared with lower light intensities, but the highest astaxanthin amounts were produced under 70 μmol m-2 s-1 of blue LED (B-70). Transcripts of astaxanthin biosynthesis genes psy, crtO, and bkt2 were upregulated under W-150, while psy, lcy, crtO, and crtR-B were upregulated by B-70...
December 4, 2017: Bioresource Technology
Xiang Cheng, ZhenBang Qi, Thomas Burdyny, Tian Kong, David Sinton
This study demonstrates the efficacy of low pressure supercritical CO2 extraction of astaxanthin from disrupted Haematococcus pluvialis. A microfluidic reactor was employed that enabled excellent control and allowed direct monitoring of the whole process at the single cell level, in real time. Astaxanthin extraction using ScCO2 achieved 92% recovery at 55 °C and 8 MPa applied over 15 h. With the addition of co-solvents, ethanol and olive oil, the extraction rates in both experiments were significantly improved reaching full recovery within a few minutes...
November 23, 2017: Bioresource Technology
Farouk K El-Baz, Rehab A Hussein, Khaled Mahmoud, Sayeda M Abdo
Microalgae represent a rich source that satisfies the growing need for novel ingredients of nutriceuticals, pharmaceuticals, and food supplements. Haematococcus pluvialis and Dunaliella salina microalgae are isolated from the Egyptian hydro-flora and are reported for their potent antioxidant activities. The cytotoxic activity of different fractions of both microalgae was investigated on 4 cell lines HePG2, MCF7, HCT116, and A549. The carotenoid rich fraction of H. pluvialis showed potent cytotoxic activity against colon cancer cell line and moderate activity against both liver and breast cancer cell lines...
November 29, 2017: Phytotherapy Research: PTR
Francesco Mascia, Laura Girolomoni, Marcelo J P Alcocer, Ilaria Bargigia, Federico Perozeni, Stefano Cazzaniga, Giulio Cerullo, Cosimo D'Andrea, Matteo Ballottari
Astaxanthin is a ketocarotenoid produced by photosynthetic microalgae. It is a pigment of high industrial interest in acquaculture, cosmetics, and nutraceutics due to its strong antioxidant power. Haematococcus pluvialis, a fresh-water microalga, accumulates high levels of astaxanthin upon oxidative stress, reaching values up to 5% per dry weight. H. pluvialis accumulates astaxanthin in oil droplets in the cytoplasm, while the chloroplast volume is reduced. In this work, we investigate the biochemical and spectroscopic properties of the H...
November 24, 2017: Scientific Reports
Tianyou Cheng, Xiaoying Xu, Wei Zhang, Lin Chen, Tianzhong Liu
AIMS: To establish a proper protoplast-preparation route from enriched motile flagellates and non-motile resting cells of Haematococcus pluvialis. METHODS AND RESULTS: Through cultivations in two mixotrophic media, enriched Haematococcus flagellates and resting cells were respectively produced and applied in enzymatic protoplast preparations. Great differences of enzymatic sensitivity and osmotic-lability were identified between them. Flagellates showed the same osmotic-lability as protoplasts and the ECM (extracellular matrix)-removing rate was applied for an evaluation of protoplast-releasing...
November 20, 2017: Journal of Applied Microbiology
Geng-Ming Lin, Yu-Heng Lai, Gilbert Audira, Chung-Der Hsiao
Green algae, Chlorella ellipsoidea, Haematococcus pluvialis and Aegagropila linnaei (Phylum Chlorophyta) were simultaneously decoded by a genomic skimming approach within 18-5.8-28S rRNA region. Whole genomic DNAs were isolated from green algae and directly subjected to low coverage genome skimming sequencing. After de novo assembly and mapping, the size of complete 18-5.8-28S rRNA repeated units for three green algae were ranged from 5785 to 6028 bp, which showed high nucleotide diversity (π is around 0.5-0...
November 6, 2017: International Journal of Molecular Sciences
Xixian Wang, Lihui Ren, Yetian Su, Yuetong Ji, Yaoping Liu, Chunyu Li, Xunrong Li, Yi Zhang, Wei Wang, Qiang Hu, Danxiang Han, Jian Xu, Bo Ma
Raman-activated cell sorting (RACS) has attracted increasing interest, yet throughput remains one major factor limiting its broader application. Here we present an integrated Raman-activated droplet sorting (RADS) microfluidic system for functional screening of live cells in a label-free and high-throughput manner, by employing AXT-synthetic industrial microalga Haematococcus pluvialis (H. pluvialis) as a model. Raman microspectroscopy analysis of individual cells is carried out prior to their microdroplet encapsulation, which is then directly coupled to DEP-based droplet sorting...
November 9, 2017: Analytical Chemistry
Yoon Young Choi, Min Eui Hong, Eon Seon Jin, Han Min Woo, Sang Jun Sim
The aim of this study is investigate the effect of column diameter (D), height/diameter (H/D) ratio, and gas flow rate on microalgae cultivation, Haematococcus pluvialis. Bubble column reactors with various D and H/D ratio were tested to assess the hydrodynamic properties and biomass production performance. Then, H. pluvialis was cultured under outdoor autotrophic conditions using industrial flue gas. By optimizing the reactor module, reactor volume increased to 354% with minimized biomass loss. Compared to the control, developed module showed biomass and astaxanthin productivity of 0...
October 16, 2017: Bioresource Technology
A Ligia Focsan, Nikolay E Polyakov, Lowell D Kispert
Abstract The antioxidant astaxanthin is known to accumulate in Haematococcus pluvialis algae under unfavorable environmental conditions for normal cell growth. The accumulated astaxanthin functions as a protective agent against oxidative stress damage, and tolerance to excessive reactive oxygen species (ROS) is greater in astaxanthin-rich cells. The detailed mechanisms of protection have remained elusive, however, our Electron Paramagnetic Resonance (EPR), optical and electrochemical studies on carotenoids suggest that astaxanthin's efficiency as a protective agent could be related to its ability to form chelate complexes with metals and to be esterified, its inability to aggregate in the ester form, its high oxidation potential and the ability to form proton loss neutral radicals under high illumination in the presence of metal ions...
October 21, 2017: Antioxidants (Basel, Switzerland)
Ruijuan Ma, Yan Li, Yinghua Lu
The PII signaling protein is a key protein for controlling nitrogen assimilatory reactions in most organisms, but little information is reported on PII proteins of green microalga Haematococcus pluvialis. Since H. pluvialis cells can produce a large amount of astaxanthin upon nitrogen starvation, its PII protein may represent an important factor on elevated production of Haematococcus astaxanthin. This study identified and isolated the coding gene (HpGLB1) from this microalga. The full-length of HpGLB1 was 1222 bp, including 621 bp coding sequence (CDS), 103 bp 5' untranslated region (5' UTR), and 498 bp 3' untranslated region (3' UTR)...
October 11, 2017: Marine Drugs
A K M Mofasser Hossain, Margaret A Brennan, Susan L Mason, Xinbo Guo, Xin An Zeng, Charles S Brennan
Marine-based food supplements can improve human nutrition. In an effort to modulate glycaemic response and enhance nutritional aspects, marine-derived algal food rich in astaxanthin was used in the formulation of a model food (wholemeal cookie). Astaxanthin substitution of cookies made from three flours (wheat, barley and oat) demonstrated a significant reduction in the rate of glucose released during in vitro digestion together with an increase in the total phenolic content (TPC) and antioxidant capacity of the food...
July 26, 2017: Foods (Basel, Switzerland)
Yu-Ju Lin, Jui-Jen Chang, Hao-Yeh Lin, Caroline Thia, Yi-Ying Kao, Chieh-Chen Huang, Wen-Hsiung Li
In this study, an astaxanthin-biosynthesis Kluyveromyces marxianus strain Sm23 was first constructed, which could produce 31µg/g DCW astaxanthin. Then, repeated genome integration of the key astaxanthin biosynthesis genes Hpchyb and bkt was done to increase gene copy number and astaxanthin yield. Four improved strains were obtained and the yield of astaxanthin and the total yield of carotenoids in a strain increased with the copy numbers of Hpchyb and bkt. To improve the yield further, the gene Hpchyb from Haematococcus pluvialis was modified by site-directed mutagenesis to increase the enzyme efficiency or/and to prevent the heterologous protein degradation by ubiquitination...
December 2017: Bioresource Technology
Ewelina Pogorzelska, Jolanta Godziszewska, Marta Brodowska, Agnieszka Wierzbicka
Astaxanthin is proven to be one of the most potent, naturally occurring antioxidants. A rich source of astaxanthin is algae Haematoccocus pluvialis (H. pluvialis). The aim of the study was to investigate antioxidant effect of H. pluvalis extract added in different levels (0.15, 0.3 or 0.45g/kg of meat) on colour and oxidative stability of raw ground pork meat during refrigerated storage (7days). Obtained data revealed that DPPH scavenging activity of the extract at the concentration of 0.45g/kg of meat was as high as 85%...
January 2018: Meat Science
Weiwei Wei, Kang Xiao, Ming Tao, Lifu Nie, Dan Liu, Shanming Ke, Xierong Zeng, Zhangli Hu, Peng Lin, Yu Zhang
The freshwater unicellular microalga Haematococcus pluvialis (H. pluvialis) has gained increasing attention because of its high-value metabolite astaxanthin, a super anti-oxidant. For the maximum astaxanthin production, a key problem is how to determine the senescent green vegetative phase of H. pluvialis cells to apply the astaxanthin production inducers. The conventional methods are time-consuming and laborious. In this study, a novel platform based on organic electrochemical transistor (OECT) was produced...
August 31, 2017: Sensors
Lo'ai Alanagreh, Caitlin Pegg, Amritha Harikumar, Mark Buchheim
Primary and secondary structural data from the internal transcribed spacer two (ITS2) have been used extensively for diversity studies of many different eukaryotic organisms, including the green algae. Ease of amplification is due, at least in part, to the fact that ITS2 is part of the tandemly-repeated rRNA array. The potential confounding influence of intragenomic variability has yet to be addressed except in a few organisms. Moreover, few of the assessments of intragenomic variation have taken advantage of the deep sequencing capacity of sequence-by-synthesis protocols...
2017: PloS One
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