Query: Haematococcus pluvialis

title: Integrated ultrasound assisted liquid biphasic flotation for efficient extraction of astaxanthin from Haematococcus pluvialis.
abstract: The purpose of this investigation is to evaluate the implementation of ultrasound assisted liquid biphasic flotation (LBF) system for the recovery of natural astaxanthin from Haematococcus pluvialis microalgae. Various operating conditions of ultrasound assisted LBF systems such as the position of ultrasound horn, mode of ultrasonication (pulse and continuous) amplitude of ultrasonication, air flowrate, duration of air flotation, and mass of H. pluvialis microalgae were evaluated. The effect of ultrasonication on the cellular morphology of microalgae was also assessed using microscopic analysis. Under the optimized operating conditions of UALBF, the maximum recovery yield, extraction efficiency, and partition coefficient of astaxanthin were 95.08 3.02% 99.74 0.05% and 185.09 4.78, respectively. In addition, the successful scale up operation of ultrasound assisted LBF system verified the practicability of this integrated approach for an effective extraction of natural astaxanthin.

title: Biotechnological production of astaxanthin from the microalga Haematococcus pluvialis.
abstract: Although biotechnologies for astaxanthin production from Haematococcus pluvialis have been developed for decades and many production facilities have been established throughout the world, the production cost is still high. This paper is to evaluate the current production processes and production facilities, to analyze the R&D strategies for process improvement, and to review the recent research advances shedding light on production cost reduction. With these efforts being made, we intent to conclude that the production cost of astaxanthin from Haematococcus might be substantially reduced to the levels comparable to that of chemical astaxanthin through further R&D and the future research might need to focus on strain selection and improvement, cultivation process optimization, innovation of cultivation methodologies, and revolution of extraction technologies.

title: Astaxanthin and other Nutrients from Haematococcus pluvialis Multifunctional Applications
abstract: Bioactive compounds of natural origin are gaining increasing popularity. High biological activity and bioavailability, beneficial effects on health and safety of use are some of their most desirable features. Low production and processing costs render them even more attractive. Microorganisms have been used in the food, medicinal, cosmetic and energy industries for years. Among them, microalgae have proved to be an invaluable source of beneficial compounds. Haematococcus pluvialis is known as the richest source of natural carotenoid called astaxanthin. In this paper, we focus on the cultivation methods of this green microalga, its chemical composition, extraction of astaxanthin and analysis of its antioxidant, anti inflammatory, anti diabetic and anticancer activities. H. pluvialis, as well as astaxanthin can be used not only for the treatment of human and animal diseases, but also as a valuable component of diet and feed.

title: Study on mechanism of synthetic astaxanthin and Haematococcus pluvialis improving the growth performance and antioxidant capacity under acute hypoxia stress of golden pompano (Trachinotus ovatus) and enhancing anti inflammatory by activating Nrf2 ARE pathway to antagonize the NF kB pathway
abstract: A nutritional feeding experiment with synthetic astaxanthin and Haematococcus pluvialis supplemented was conducted to determine growth performance, antioxidant capacity and anti inflammation in golden pompano (Trachinotus ovatus).Three diets were formulated with or without H. pluvialis and synthetic astaxanthin supplemented to feed fish for 8 weeks. As the results showed, growth performance (FBW, WG and SGR) significantly increased with synthetic astaxanthin and H. Pluvialis supplemented. Feed coefficient ratio (FCR) of T. ovatus fed diets with H. Pluvialis and astaxanthin supplemented was lower than that of fish fed the control diet. The hepatic total antioxidant capacity (T AOC) in T. ovatus fed diet with H. Pluvialis and astaxanthin supplemented was higher than that of fish fed the control one. Superoxide dismutase (SOD) and hepatic malondialdehyde (MDA) declined slightly with astaxanthin and H. Pluvialis supplementated than that in control group without significant differences. Under normal rearing experiments, there was no significant difference among the treatments in Nrf2 ARE related genes. However, after the acute hypoxia trial, the relative expression of Nrf2, Keap1, CAT, SOD, GSH PX and HO 1 were all significantly higher in astaxanthin and H. Pluvialis treatments than that in the control group. After LPS administration, the mRNA relative expression of Nrf2 ARE related genes including Keap1, Nrf2, CAT, GSH PX, HO 1 and SOD were all significantly higher in astaxanthin and H. Pluvialis treatments than that in the control group. The mRNA relative expression of NF kB related genes IKK, IkB, and P65 as well as IL1b were all significantly lower in astaxanthin and H. Pluvialis treatments than that in the control group. These results indicated that dietary astaxanthin and H. Pluvialis improved the growth performance and antioxidant capacity under acute hypoxia stress, and alleviated the inflammatory response by activating Nrf2 ARE pathway to antagonize the NF kB pathway.

title: A strategy for stimulating astaxanthin and lipid production in Haematococcus pluvialis by exogenous glycerol application under low light
abstract: In large scale outdoor cultivation, Haematococcus pluvialis cultures are frequently exposed to low light caused by continuous rain conditions. Low light significantly restricts biomass and astaxanthin accumulation, thereby decreasing astaxanthin productivity. In this study, the effects of exogenous glycerol on the growth, photosynthesis, and astaxanthin and lipid accumulation in H. pluvialis under low light were investigated. A strategy was developed for promoting astaxanthin and lipid production in H. pluvialis under low light by the application of exogenous glycerol. Under low light, exogenous glycerol did not change the biomass and photosynthetic capacity of H. pluvialis. The addition of 1 mL L 1 glycerol increased total lipid content by 36.8% by increasing the formation of fatty acids during an 11 day growth period. Furthermore, exogenous glycerol could directly accelerate astaxanthin production under low light by increasing the formation of substrates (e.g. pyruvate) Meanwhile, the elevated fatty acid level due to the addition of glycerol facilitated the esterification of astaxanthin, thereby accelerating the biosynthesis of astaxanthin indirectly, which is indicated by the fact that exogenous glycerol enhanced astaxanthin esters content significantly under low light. All these results suggest that H. pluvialis has the ability to utilize glycerol for astaxanthin and lipid production under low light.

title: Primary metabolism is associated with the astaxanthin biosynthesis in the green algae Haematococcus pluvialis under light stress
abstract: Haematococcus pluvialis is a kind of native bioresource, which accumulate high abundance of astaxanthin, one of the most important bioactive compounds, under various biotic and abiotic stress conditions particularly under high light. However, the global metabolic responses to high light in general and the relationship between primary metabolism and astaxanthin accumulation in particular are still obscure. In this study, non targeted metabolomics approach was first to be used to profile the dynamic metabolic changes of H. pluvialis along astaxanthin accumulation under different light intensities, in which >200 low molecular metabolites were identified. The integration of metabolomics data with previous transcriptomic data uncovered several metabolic pathways including raffinose family oligosaccharides biosynthesis pathway, GSH metabolism pathways, pyrimidine and purine metabolism pathways, TCA cycle, and phospholipids, that are important for astaxanthin biosynthesis under high light intensity, pinpointing a metabolic shift from primary metabolism to astaxanthin biosynthesis. Exogenous application of related metabolites such as nucleotides, carbohydrates and amino acids in algal medium confirmed the metabolic link between primary metabolism and astaxanthin biosynthesis. Our results provides with a solid metabolic base for the manipulation of astaxanthin production under high light stress, and reveals metabolic insights into the adaption strategy of H. pluvialis against light stress conditions.

title: Isolation of astaxanthin monoesters from the microalgae Haematococcus pluvialis by high performance countercurrent chromatography (HPCCC) combined with high performance liquid chromatography (HPLC)
abstract: Astaxanthin is a potent natural antioxidant with beneficial bioactivities demonstrated primarily for its free (non esterified) form. However, its natural producer, the microalgae Haematococcus pluvialis synthesizes astaxanthin mostly in ester forms which have been little valorized so far. Hence, to contribute to the commercial use of astaxanthin esters, a scalable and efficient isolation technology is required. In this study, five astaxanthin monoesters were isolated from H. pluvialis using high performance countercurrent chromatography (HPCCC) where the lower phase of a biphasic solvent system (n heptane:acetonitrile, ratio 5:5, v/v) was used as a mobile phase. Around 200 mg of biomass extract was subjected to the HPCCC leading to a separation of the target astaxanthin esters. To further increase the process productivity, a multi injection HPCCC method was developed by combining two elution modes (reverse phase and co current) In co current elution mode, both the mobile and stationary phases were pumped simultaneously at flow rates of 3 and 1 mL/min respectively, so that the stationary phase that gets lost during each separation cycle is replenished. In total, five injections of samples (200 mg of extract, each) were achieved. Final purification with high performance liquid chromatography (HPLC) afforded five astaxanthin derivatives esterified with a linolenic acid (1, 4 mg) linoleic acid (2, 8 mg) palmitic acid (3, 8 mg) oleic acid (4, 12 mg) and stearic acid (5, 1 mg) with purities of 98% as determined by HPLC analysis. Only compound 4 exhibited a cytotoxic effect against human gastric cancer cells. The present study shows a useful approach for obtaining individual astaxanthin esters from H. pluvialis.

title: Comparison of effect of dietary supplementation with Haematococcus pluvialis powder and synthetic astaxanthin on carotenoid composition, concentration, esterification degree and astaxanthin isomers in ovaries, hepatopancreas, carapace, epithelium of adult female Chinese mitten crab (Eriocheir sinens
abstract: Astaxanthin is widely used in aquaculture, being added to feeds to give desirable coloration to the farmed animals. Little is known about the different effects of natural and synthetic astaxanthin on Chinese mitten crab (Eriocheir sinensis) This study was conducted to compare the effects of dietary supplementation with Haematococcus pluvialis powder and synthetic astaxanthin on carotenoid composition, concentration, degree of esterification and astaxanthin isomers of E. sinensis. Six experimental diets were formulated including a basal diet, three diets containing H. pluvialis powder (0.2% 0.4% 0.6% and two diets containing synthetic astaxanthin (0.13% 0.16% with each diet being fed to female crabs (average body weight of 85 5 g) in triplicate tanks with 12 crabs in each. After feeding for 30 and 60 days, the ovaries, hepatopancreas, carapace and epithelium of 3 crabs from each tank were taken for carotenoid analysis. Dietary supplementation with H. pluvialis powder and synthetic astaxanthin increased the astaxanthin concentration of E. sinensis in a dose dependent manner. After 60 days, the astaxanthin concentration in body parts of crabs from high to low were ovaries (45.19 343.37 mg/kg) epithelium (14.98 37.74 mg/kg) carapace (12.86 21.71 mg/kg) and hepatopancreas (0.49 8.75 mg/kg) Astaxanthin in the epithelium was found in esterified form but in other body parts the astaxanthin was not esterified. All trans astaxanthin was predominant in the ovaries, epithelium and carapace, and the proportion varied from 59.74% to 96.94% (3S,3'S) astaxanthin was mostly deposited in the ovaries of crabs fed with diets containing H. pluvialis powder and the proportion (85.18% 96.27% increased significantly with increasing astaxanthin concentration of diets. Differences of astaxanthin isomers between diets and body parts indicated that isomers were deposited selectively and were likely to be accompanied by isomerization. To achieve the same effect on body astaxanthin concentration, synthetic astaxanthin required a higher level of addition than H. pluvialis powder. These results suggest that H. pluvialis powder is more effective in astaxanthin accumulation of E. sinensis, and also improves carotenoid and astaxanthin isomer composition of E. sinensis in comparison with synthetic astaxanthin.

title: Enhancement of astaxanthin production by Haematococcus pluvialis using magnesium aminoclay nanoparticles.
abstract: Improving the content and production of high value ketocarotenoid pigments is critical for the commercialization of microalgal biorefineries. This study reported the use of magnesium aminoclay (MgAC) nanoparticles for enhancement of astaxanthin production by Haematococcus pluvialis in photoautotrophic cultures. Addition of 1.0 g/L MgAC significantly promoted cellular astaxanthin biosynthesis (302 69 pg/cell) presumably by inducing tolerable oxidative stress, corresponding to a 13.7 fold higher production compared to that in the MgAC untreated control (22 2 pg/cell) The lipid content and cell size of H. pluvialis improved by 13.6 and 2.1 fold, respectively, compared to that of the control. Despite reduced cell numbers, the overall astaxanthin production (10.3 0.4 mg/L) improved by 40% compared to the control (7.3 0.6 mg/L) owing to improved biomass production. However, an MgAC dosage above 1.0 g/L inhibited biomass production by inducing electrostatic cell wall destabilization and aggregation. Therefore, MgAC induced stimulation of algae varies widely based on their morphological and physiological characteristics.

title: Recent advances in biorefinery of astaxanthin from Haematococcus pluvialis.
abstract: Haematococcus pluvialis is one of the most abundant sources of natural astaxanthin as compared to others microorganism. Therefore, it is important to understand the biorefinery of astaxanthin from H. pluvialis, starting from the cultivation stage to the downstream processing of astaxanthin. The present review begins with an introduction of cellular morphologies and life cycle of H. pluvialis from green vegetative motile stage to red non motile haematocyst stage. Subsequently, the conventional biorefinery methods (e.g. mechanical disruption, solvent extraction, direct extraction using vegetable oils, and enhanced solvent extraction) and recent advanced biorefinery techniques (e.g. supercritical CO2 extraction, magnetic assisted extraction, ionic liquids extraction, and supramolecular solvent extraction) were presented and evaluated. Moreover, future prospect and challenges were highlighted to provide a useful guide for future development of biorefinery of astaxanthin from H. pluvialis. The review aims to serve as a present knowledge for researchers dealing with the bioproduction of astaxanthin from H. pluvialis.