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Bioresources and Bioprocessing Nov 2023Large amounts of astaxanthin (about 4% DW) can be produced under nitrogen starvation of Haematococcus pluvialis in photobioreactors (PBRs) exposed to high light...
Large amounts of astaxanthin (about 4% DW) can be produced under nitrogen starvation of Haematococcus pluvialis in photobioreactors (PBRs) exposed to high light conditions to induce a light stress. However, in PBR, the large biomass concentration usually achieved leads to strong light attenuation conditions, which makes complex the analysis of this "light stress". This study aims to elucidate the role of light transfer in astaxanthin cell content and productivity from the microalga Haematococcus pluvialis during nitrogen starvation. Haematococcus pluvialis was cultivated in a flat-panel PBR in a batch mode with sudden nitrogen starvation conditions and an incident photon flux density (PFD) of 250 µmol m s. Different initial biomass concentrations ( ) were evaluated, 0.21, 0.52, 1.39 and 2.21 kg m. As a result, spectral mass absorption cross-sections of Haematococcus pluvialis were measured at different times during nitrogen starvation, and were used to relate the mean rate of photon absorption (MRPA) to the astaxanthin productivity. A minimum initial MRPA of 7000 ± 500 µmol kg s was found necessary to trigger large accumulation of astaxanthin in Haematococcus pluvialis cells (up to 3.21% DW) during nitrogen starvation conditions. The results also demonstrated the link between the MRPA and the daily astaxanthin productivity of Haematococcus pluvialis cultures, introducing then the MRPA as a physical quantity of interest for a rational optimization of the light culture conditions in PBRs.
PubMed: 38647902
DOI: 10.1186/s40643-023-00700-0 -
Redox Report : Communications in Free... Dec 2024The study aimed to assess the role of Astaxanthin (ATX) in palmitic acid(PA) -induced bone loss in Ovariectomized(OVX) rats.
OBJECTIVES
The study aimed to assess the role of Astaxanthin (ATX) in palmitic acid(PA) -induced bone loss in Ovariectomized(OVX) rats.
METHODS
In the OVX rat model, we observed that PA affects bone metabolism and accelerates bone loss. Additionally, treatment with ATX was able to suppress the deleterious effects of PA and a simultaneous decrease in serum MDA levels and an increase in SOD was observed.
RESULTS
In addition, rats treated with ATX were observed to have significantly increased bone mass and elevated activity of SIRT1 and SOD2 in bone tissue. When MC3T3-E1 and RAW264.7 cells induced osteoblast and osteoclast differentiation, the ATX intervention was able to significantly restore the restriction of osteogenic differentiation and the up-regulation of osteoclast differentiation with PA therapy. Furthermore, we confirm that PA damage to cells is caused by increased oxidative stress, and that ATX can target and modulate the activity of SIRT1 to regulate the levels of oxidative stress in cells.
CONCLUSION
Summarizing, ATX may inhibit PA-induced bone loss through its antioxidant properties via the SIRT1 signaling pathway.
Topics: Rats; Animals; Osteoporosis; Osteogenesis; Palmitic Acid; Sirtuin 1; Cell Differentiation; Oxidative Stress; Xanthophylls
PubMed: 38623993
DOI: 10.1080/13510002.2024.2333096 -
Scientific Reports Apr 2024This study aimed to establish an astaxanthin-rich strain of the calanoid copepod Pseudodiaptomus annandalei, through selective breeding based on RGB (red, green and...
This study aimed to establish an astaxanthin-rich strain of the calanoid copepod Pseudodiaptomus annandalei, through selective breeding based on RGB (red, green and blue) value, a parameter indicating color intensity. We evaluated the RGB value frequency distributions of the copepod populations, and selected individuals with the highest 10% and the lowest 10% RGB value over six generations. The RGB value, nauplii production, clutch interval and clutch number were assessed, and the genetic gain was calculated across generations (G-G). Two strains of copepods were selected and defined as dark body copepod strain (DBS) and light body copepod strain (LBS) at the end of experiment. Results revealed significantly lower RGB values (male: 121.5 ± 14.1; female: 108.8 ± 15) in the G DBS population compared to the G (male: 163.9 ± 13.1; female: 162.2 ± 14.6), with higher genetic gains of RGB values during G to G. While DBS females exhibited longer clutch intervals in the G and G, there was no significant difference in nauplii production between the two strains across all generations. Significantly higher astaxanthin content was found in the DBS copepods (0.04 μg/ ind.) compared to the LBS copepods (0.01 μg/ ind.) and the non-selective copepods (0.02 μg/ ind.) 20 months post selective breeding, validating the stability of the desired trait in the DBS strain. This study successfully established an astaxanthin-rich strain of P. annandalei, which provides implications for enhancing marine and brackish larviculture production.
Topics: Animals; Female; Male; Copepoda; Xanthophylls
PubMed: 38622162
DOI: 10.1038/s41598-024-59224-y -
Foods (Basel, Switzerland) Mar 2024In this study, we investigated the body characteristics, carotenoid composition, and nutritional quality of with different hepatopancreas redness (). We distributed the...
In this study, we investigated the body characteristics, carotenoid composition, and nutritional quality of with different hepatopancreas redness (). We distributed the crabs into two groups based on the hepatopancreas values and compared their body characteristics, chroma, carotenoid composition, and protein, lipid, total sugar, amino acid, and fatty acid content via paired -test. The results revealed that the relationships between hepatopancreas values and crab quality are sex specific. In female crabs, the differences in nutritional characteristics were evident mainly in the hepatopancreases and ovaries. In the redder hepatopancreases, the content of zeaxanthin and β-carotene increased, and the levels of C22:6n3 and C20:5n3 decreased ( < 0.05). In the ovaries, the content of astaxanthin, canthaxanthin, β-carotene, umami, and sweet amino acids were lower in the redder hepatopancreas crabs ( < 0.05). In male crabs, there were positive relationships between hepatopancreas and amino acid and fatty acid content. The content of leucine, arginine, and total umami amino acids in muscles and of unsaturated fatty acids and n-6 polyunsaturated fatty acids in hepatopancreases and testicles increased with increasing hepatopancreas values ( < 0.05). Therefore, the redder the hepatopancreas, the higher the nutritional quality of male crabs.
PubMed: 38611298
DOI: 10.3390/foods13070993 -
Heliyon Apr 2024To ascertain their potential for heavy metal pollution remedy, we studied the adsorption mechanism of cadmium onto scallop shells and the interactions between the heavy...
To ascertain their potential for heavy metal pollution remedy, we studied the adsorption mechanism of cadmium onto scallop shells and the interactions between the heavy metal and the shell matrix. Intact shells were used to investigate the uptake and diffusion of the metal contaminant onto the shell carbonatic layers, as well as to evaluate the distribution of major and trace elements in the matrix. LA-ICPMS measurements demonstrate that Cd is adsorbed on a very thin layer on the inner and outer surfaces of the shell. Structural and thermal analyses showed the presence of 9 wt.-% of a CdCO phase indicating that the adsorption is mainly a superficial process which involves different processes, including ion exchange of Ca by Cd. In addition, organic components of the shell could contribute to adsorption as highlighted by different metal uptake observed for shells with different colours. In particular, darker shells appeared to adsorb more contaminant than the white ones. The contribution of the organic shell components on the adsorption of heavy metals was also highlighted by the element bulk content which showed higher concentrations of different metals in the darker specimen. Raman spectroscopy allowed to identify the pigments as carotenoids, confirmed by XRD measurements which highlighted the presence of astaxanthin phases. The results presented here provide new insights into the Cd adsorption mechanism highlighting the important contribution given by the organic components present in the biogenic carbonate matrix. Furthermore, the high efficiency of Cd removal from water by scallop shells, supported by adsorption kinetic and isotherm studies, has been demonstrated.
PubMed: 38601540
DOI: 10.1016/j.heliyon.2024.e29296 -
Scientific Reports Apr 2024Astaxanthin, a versatile C40 carotenoid prized for its applications in food, cosmetics, and health, is a bright red pigment with powerful antioxidant properties. To...
Astaxanthin, a versatile C40 carotenoid prized for its applications in food, cosmetics, and health, is a bright red pigment with powerful antioxidant properties. To enhance astaxanthin production in Corynebacterium glutamicum, we employed rational pathway engineering strategies, focused on improving precursor availability and optimizing terminal oxy-functionalized C40 carotenoid biosynthesis. Our efforts resulted in an increased astaxanthin precursor supply with 1.5-fold higher β-carotene production with strain BETA6 (18 mg g CDW). Further advancements in astaxanthin production were made by fine-tuning the expression of the β-carotene hydroxylase gene crtZ and β-carotene ketolase gene crtW, yielding a nearly fivefold increase in astaxanthin (strain ASTA**), with astaxanthin constituting 72% of total carotenoids. ASTA** was successfully transferred to a 2 L fed-batch fermentation with an enhanced titer of 103 mg L astaxanthin with a volumetric productivity of 1.5 mg L h. Based on this strain a pathway expansion was achieved towards glycosylated C40 carotenoids under heterologous expression of the glycosyltransferase gene crtX. To the best of our knowledge, this is the first time astaxanthin-β-D-diglucoside was produced with C. glutamicum achieving high titers of microbial C40 glucosides of 39 mg L. This study showcases the potential of pathway engineering to unlock novel C40 carotenoid variants for diverse industrial applications.
Topics: Carotenoids; Corynebacterium glutamicum; Xanthophylls; beta Carotene; Metabolic Engineering
PubMed: 38582923
DOI: 10.1038/s41598-024-58700-9 -
Frontiers in Bioengineering and... 2024Valorization of food processing effluent (FPE) by microalgae cultivation for astaxanthin production is regarded as a potential strategy to solve the environmental... (Review)
Review
Cultivation of microalgae in food processing effluent for pollution attenuation and astaxanthin production: a review of technological innovation and downstream application.
Valorization of food processing effluent (FPE) by microalgae cultivation for astaxanthin production is regarded as a potential strategy to solve the environmental pollution of food processing industry and promote the development of eco-friendly agriculture. In this review paper, microalgal species which have the potential to be employed for astaxanthin in FPE were identified. Additionally, in terms of CO emission, the performances of microalgae cultivation and traditional methods for FPE remediation were compared. Thirdly, an in-depth discussion of some innovative technologies, which may be employed to lower the total cost, improve the nutrient profile of FPE, and enhance the astaxanthin synthesis, was provided. Finally, specific effects of dietary supplementation of algal astaxanthin on the growth rate, immune response, and pigmentation of animals were discussed. Based on the discussion of this work, the cultivation of microalgae in FPE for astaxanthin production is a value-adding process which can bring environmental benefits and ecological benefits to the food processing industry and agriculture. Particularly, technological innovations in recent years are promoting the shift of this new idea from academic research to practical application. In the coming future, with the reduction of the total cost of algal astaxanthin, policy support from the governments, and further improvement of the innovative technologies, the concept of growing microalgae in FPE for astaxanthin will be more applicable in the industry.
PubMed: 38572356
DOI: 10.3389/fbioe.2024.1365514 -
Respiratory Research Mar 2024Astaxanthin (AXT) is a keto-carotenoid with a variety of biological functions, including antioxidant and antifibrotic effects. Small airway remodeling is the main...
BACKGROUND
Astaxanthin (AXT) is a keto-carotenoid with a variety of biological functions, including antioxidant and antifibrotic effects. Small airway remodeling is the main pathology of chronic obstructive pulmonary disease (COPD) and is caused by epithelial-to-mesenchymal transition (EMT) and fibroblast differentiation and proliferation. Effective therapies are still lacking. This study aimed to investigate the role of AXT in small airway remodeling in COPD and its underlying mechanisms.
METHODS
First, the model of COPD mice was established by cigarette smoke (CS) exposure combined with intraperitoneal injection of cigarette smoke extract (CSE). The effects of AXT on the morphology of CS combined with CSE -induced emphysema, EMT, and small airway remodeling by using Hematoxylin-eosin (H&E) staining, immunohistochemical staining, and western blot. In addition, in vitro experiments, the effects of AXT on CSE induced-EMT and fibroblast function were further explored. Next, to explore the specific mechanisms underlying the protective effects of AXT in COPD, potential targets of AXT in COPD were analyzed using network pharmacology. Finally, the possible mechanism was verified through molecular docking and in vitro experiments.
RESULTS
AXT alleviated pulmonary emphysema, EMT, and small airway remodeling in a CS combined with CSE -induced mouse model. In addition, AXT inhibited the EMT process in airway cells and the differentiation and proliferation of fibroblasts. Mechanistically, AXT inhibited myofibroblast activation by directly binding to and suppressing the phosphorylation of AKT1. Therefore, our results show that AXT protects against small airway remodeling by inhibiting AKT1.
CONCLUSIONS
The present study identified and illustrated a new food function of AXT, indicating that AXT could be used in the therapy of COPD-induced small airway remodeling.
Topics: Mice; Animals; Cigarette Smoking; Airway Remodeling; Molecular Docking Simulation; Signal Transduction; Pulmonary Disease, Chronic Obstructive; Pulmonary Emphysema; Nicotiana; Xanthophylls
PubMed: 38555458
DOI: 10.1186/s12931-024-02768-4 -
Frontiers in Microbiology 2024Nowadays the increasing amount of saline wastewaters has given rise to various biological desalination processes, among which the application possibilities of microalgae...
Nowadays the increasing amount of saline wastewaters has given rise to various biological desalination processes, among which the application possibilities of microalgae represents a priority research area. Next to "real" aquatic species (members of phytoplankton or phytobenthon), species from ephemeral aquatic habitats or aeroterrestrial algae also could be good candidates of research studying salt tolerance or desalination ability, since salinity stress is often referred as "physiological drought" and species from ephemeral habitats can be characterized by high drought tolerance. In this study, the salinity tolerance, salt and nutrient removal ability of a strain from eastern Hungary were investigated. Vegetative cells showed low salt tolerance, survival was ensured by the formation of cysts up to a sodium-chloride concentration of 2,000 mg l. Although relatively moderate (a max. 30%) conductivity reduction and chloride removal were observed, notable (nearly 100%) nitrate and phosphate removal occurred even in the presence of 2,000 mg l NaCl. Carotenoid accumulation was observed earlier and in higher extent in salt treated cultures than in drying out ones, although the amount of astaxanthin-esters was significantly higher in the cultures of drying out experiment than in the corresponding cultures of salt treatment characterized with similar chloride content. Our results suggest that algae isolates from ephemeral aquatic habitats endangered by regular drying out (exposed to special salt stress), could have notable salt tolerance and consequently successful applicability in nutrient removal processes from slightly saline wastewaters. The accumulation of valuable metabolites (such as astaxanthin) as a response to salinity stress, could enhance the economic value of the biomass.
PubMed: 38550863
DOI: 10.3389/fmicb.2024.1332642 -
Molecules (Basel, Switzerland) Mar 2024The oral delivery strategy of natural anti-oxidant and anti-inflammatory agents has attracted great attention to improve the effectiveness of ulcerative colitis (UC)...
The oral delivery strategy of natural anti-oxidant and anti-inflammatory agents has attracted great attention to improve the effectiveness of ulcerative colitis (UC) treatment. Herein, we developed a novel orally deliverable nanoparticle, carboxymethyl chitosan (CMC)-modified astaxanthin (AXT)-loaded nanoparticles (CMC-AXT-NPs), for UC treatment. The CMC-AXT-NPs were evaluated by appearance, morphology, particle size, ζ-potential, and encapsulation efficiency (EE). The results showed that CMC-AXT-NPs were nearly spherical in shape with a particle size of 34.5 nm and ζ-potential of -30.8 mV, and the EE of CMC-AXT-NPs was as high as 95.03%. The CMC-AXT-NPs exhibited preferable storage stability over time and well-controlled drug-release properties in simulated intestinal fluid. Additionally, in vitro studies revealed that CMC-AXT-NPs remarkably inhibited cytotoxicity induced by LPS and demonstrated superior antioxidant and anti-inflammatory abilities in Raw264.7 cells. Furthermore, CMC-AXT-NPs effectively alleviated clinical symptoms of colitis induced by dextran sulfate sodium salt (DSS), including maintaining body weight, inhibiting colon shortening, and reducing fecal bleeding. Importantly, CMC-AXT-NPs suppressed the expression of pro-inflammatory cytokines like TNF-α, IL-6, and IL-1β and ameliorated DSS-induced oxidative damage. Our results demonstrated the potential of CMC-modified nanoparticles as an oral delivery system and suggested these novel AXT nanoparticles could be a promising strategy for UC treatment.
Topics: Humans; Colitis, Ulcerative; Chitosan; Nanoparticles; Anti-Inflammatory Agents; Dextran Sulfate; Colitis; Xanthophylls
PubMed: 38542929
DOI: 10.3390/molecules29061291