Synthesis, stability and bioavailability of astaxanthin succinate diester

Effects of microencapsulation in dairy matrix on the quality characteristics and bioavailability of docosahexaenoic acid astaxanthin

BACKGROUND

Compared with free astaxanthin (Asta), docosahexaenoic acid astaxanthin monoester (Asta-C22:6) has higher stability and bioavailability. However, Asta-E is still unable to be used in the water system. Hence it is necessary to build a water-soluble delivery system. In this study, Asta-C22:6 microemulsion and microcapsule using whey protein isolate (WPI) and hydroxypropyl-β-cyclodextrin (HPβ-CD) as composite wall material were prepared. They were added to three dairy products (milk powder, yogurt and flavored dairy product). A dairy product rich in Asta-C22:6 with high bioavailability was designed by measuring quality characteristics, sensory evaluation and in vivo experiments.

RESULTS

Compared with spray drying, the freeze-drying microcapsule had a higher encapsulation efficiency (72.5%), water content (4%) and better solubility, and Asta-C22:6 microcapsule (1 g L^-1 ) yogurt had the best quality. The bioavailability of Asta-C22:6 microcapsule yogurt was further evaluated. After a single oral dose in mice, the bioavailability of Asta-C22:6 microcapsule in yogurt was significantly increased (C_max  = 0.31 μg mL^-1 , AUC_0-T  = 3.20 h μg mL^-1 ).

CONCLUSION

We successfully prepared Asta-C22:6 microcapsule yogurt, which improved the stability and bioavailability of Asta. The present research is meaningful for delivering unstable bioactive small molecules based on WPI and HPβ-CD. It provides an experimental basis for the application of Asta-C22:6 and the development of functional dairy products. © 2022 Society of Chemical Industry.

Esterification of Lutein from Japanese Knotweed Waste Gives a Range of Lutein Diester Products with Unique Chemical Stability

A valorization strategy for an aggravating type of plant waste is put to the test herein. It envisions the use of Japanese knotweed green leaves as a sustainable source of free lutein, from which bioactive diesters could be prepared as potential value-added products with improved properties. To this end, 13 structurally distinct model lutein diesters were synthesized and the relationships between their structure and stability were systematically determined. The forced degradation data show that the stability of a particular lutein diester may depend to a large extent on the type of exposure (elevated temperature, light, oxidant, or acidic environment) and, more importantly, not every esterification attempt necessarily leads to an enhancement of lutein's chemical stability. However, three branched and bulky products-lutein di(2,2-dimethylpropanoate), lutein di(2-methylpropanoate), and lutein di(3-methylbutanoate)-proved to be particularly relevant, as they consistently exhibited 1.5-21-fold higher stability compared to free lutein, regardless of the stress conditions used. Finally, we show that the Japanese knotweed plant matrix had a significant negative or positive effect on pigment degradation kinetics that could not be easily predicted. Thus, the proposed valorization strategy is quite feasible, but the esterification approach should be tailored to the intended use of a lutein diester.

Stability and bioavailability of protein matrix-encapsulated astaxanthin ester microcapsules

BACKGROUND

Astaxanthin ester derived from Haematococcus pluvialis is often used as a functional and nutritional ingredient in foods. However, its utilization is currently limited as a result of its chemical instability and low bioavailability. Food matrix microcapsules are becoming increasingly popular because of their safety and high encapsulation efficiency. In the present study, the effect of protein matrixes on the properties of microcapsules was evaluated.

RESULTS

We investigated the effects of storage on astaxanthin ester microcapsules and the corresponding rehydration solution at 40 °C under a nitrogen atmosphere, as well as in darkness. The results showed that the stability of products prepared based on whey protein (WP) and corn-gluten was superior to that of products prepared based on lactoferrin, soy protein and sodium caseinate. The bioavailability of astaxanthin ester microcapsules encapsulated with different proteins and examined by means of astaxanthin concentrations in the serum and liver after oral administration was compared. All five protein wall materials could significantly improve the bioavailability of astaxanthin ester. The microcapsules prepared based on WP had the highest bioavailability, with a value of 10.69 ± 0.75 μg·h mL^-1 , which was 3.15 times higher compared to that of the control group.

CONCLUSION

The results of the present study showed that protein encapsulation, especially WP encapsulation, could effectively improve the stability, water solubility and bioavailability of astaxanthin esters. Thus, WP can be used as the main wall material in delivery systems. © 2021 Society of Chemical Industry.

Mechanistic role of astaxanthin derived from shrimp against certain metabolic disorders

Oxidative stress caused by the imbalance between production of oxidants and antioxidants in the body leads to the development of different ailments. The bioactive compounds derived from marine sources are considered to be safe and appropriate to use. Astaxanthin possesses antioxidant activity about 100-500 times higher than other antioxidants such as α-tocopherol and β-carotene. It has numerous health benefits and vital pharmacological properties for the treatment of diseases like diabetes, hypertension, cancer, heart disease, ischemia, neurological disorders, and potential role in liver enzyme gamma-glutamyl transpeptidase which has significance in medicine as a diagnostic marker. The primary source of astaxanthin among crustaceans is shrimps and the presence of astaxanthin protects shrimps from oxidation of polyunsaturated fatty acids and cholesterol. Conclusively, astaxanthin derived from shrimps is very effective against oxidative stress which can lead to certain ailments.

Benefits of Exercise and Astaxanthin Supplementation: Are There Additive or Synergistic Effects?

A healthy lifestyle is essential for maintaining physical and mental health. Health promotion, with a particular emphasis on regular exercise and a healthy diet, is one of the emerging trends in healthcare. However, the way in which exercise training and nutrients from dietary intake interact with each other to promote additive, synergistic, or antagonistic effects on physiological functions leading to health promotion, and the possible underlying biomolecular mechanisms of such interactions, remain poorly understood. A healthy diet is characterized by a high intake of various bioactive compounds usually found in natural, organic, and fresh foodstuffs. Among these bioactive compounds, astaxanthin (ASX), a red carotenoid pigment especially found in seafood, has been recognized in the scientific literature as a potential nutraceutical due to its antioxidant, anti-inflammatory, and neurotrophic properties. Therefore, scientists are currently exploring whether this promising nutrient can increase the well-known benefits of exercise on health and disease prevention. Hence, the present review aimed to compile and summarize the current scientific evidence for ASX supplementation in association with exercise regimes, and evaluate the additive or synergistic effects on physiological functions and health when both interventions are combined. The new insights into the combination paradigm of exercise and nutritional supplementation raise awareness of the importance of integrative studies, particularly for future research directions in the field of health and sports nutrition science.

Influence of oil matrixes on stability, antioxidant activity, bioaccessibility and bioavailability of astaxanthin ester

BACKGROUND

Astaxanthin ester (Asta-E) is used as functional nutraceuticals in many food products. Unfortunately, Asta-E utilization is currently limited owing to its chemical instability and low bioavailability. The purpose of this study is to investigate the promotion effect of oil matrixes on the stability, antioxidant activity, bioaccessibility and bioavailability of Asta-E.

RESULTS

The results showed that the stability of Asta-E in six oil matrixes was improved. Based on the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity experiment, the antioxidant activity of Asta-E was positively correlated with the degree of unsaturation of the oil matrixes, but not with the side chain length. The in vitro gastrointestinal tract (GIT) simulation model and in vivo experiment using mice were also employed to investigate the digestion and absorption characteristics of Asta-E in various oil matrixes. The results demonstrated that the bioaccessibility and bioavailability of Asta-E increased with the increase of fatty acid chain length of oil matrixes (triglyceride oleate > triglyceride caprylate > triglyceride butyrate), as well as with the decrease of unsaturation degree (olive oil > corn oil > fish oil).

CONCLUSION

Monounsaturated fatty acids (MUFA) and long-chain triglyceride (LCT) in an oil matrix were the factors that could efficiently improve the bioavailability of Asta-E. Moreover, the size of the mixed micelles of Asta-E during digestion was the main factor influencing the bioaccessibility of Asta-E. This study provides references for the design of suitable oil matrixes for Asta-E. © 2020 Society of Chemical Industry.

Attenuation of the Na/K‑ATPase/Src/ROS amplification signaling pathway by astaxanthin ameliorates myocardial cell oxidative stress injury

The 3S, 3′S-ASTaxanthin (3S, 3′S-AST) isomer has strong antioxidant activity; however, its protective roles and potential mechanisms against oxidative stress damage in cardiomyocytes have not been investigated. Na⁺/K⁺-ATPase (NKA)/Src signal activation has an important role in increasing reactive oxygen species (ROS) production. The aim of the present study was to investigate the protective effects and mechanism of 3S, 3′S-AST on hydrogen peroxide (H₂O₂)-induced oxidative stress injury in H9c2 myocardial cells. The protective effects of 3S, 3′S-AST on H₂O₂-induced H9c2 cell injury was observed by measuring lactate dehydrogenase and creatine kinase myocardial band content, cell viability and nuclear morphology. The antioxidant effect was investigated by analyzing ROS accumulation and malondialdehyde, glutathione (GSH) peroxidase, GSH and glutathione reductase activity levels. The protein expression levels of Bax, Bcl-2, caspase-3 and cleaved caspase-3 were analyzed using western blotting to determine cardiomyocyte apoptosis. Western blot analysis of the phosphorylation levels of Src and Erk1/2 were also performed to elucidate the molecular mechanism involved. The results showed that 3S, 3′S-AST reduced the release of LDH and promoted cell viability, and attenuated ROS accumulation and cell apoptosis induced by H₂O₂. Furthermore, 3S, 3′S-AST also restored apoptosis-related Bax and Bcl-2 protein expression levels in H₂O₂-treated H9c2 cells. The phosphorylation levels of Src and Erk1/2 were significantly higher in the H₂O₂ treatment group, whereas 3S, 3′S-AST pretreatment significantly decreased the levels of phosphorylated (p)-Src and p-ERK1/2. The results provided evidence that 3S, 3′S-AST exhibited a cardioprotective effect against oxidative stress injury by attenuating NKA/Src/Erk1/2-modulated ROS amplification.

Astaxanthin n-Octanoic Acid Diester Ameliorates Insulin Resistance and Modulates Gut Microbiota in High-Fat and High-Sucrose Diet-Fed Mice

Astaxanthin n-octanoic acid diester (AOD) is a type of astaxanthin connecting medium-chain fatty acids with a more stable structure. In this study, we examined the role of AOD in ameliorating insulin resistance (IR) induced by a high-fat and high-sucrose diet (HFD) as well as its effect on modulating gut microbiota in mice, with free astaxanthin (AST) as a comparison. Four groups of male C57BL/6J mice (6 weeks old; n = 10 per group) were fed with a normal control diet (NC), HFD orally administered with AOD, AST (50 mg/kg body weight), or vehicle for 8 weeks. AOD improved glucose tolerance, IR, systematic and intestinal inflammation, and intestinal integrity better than AST. Further, both AOD and AST modulated gut microbiota. A significantly higher abundance of Bacteroides and Coprococcus was found in AOD than in AST, and the predicted pathway of carbohydrate metabolism was significantly impacted by AOD. Overall, AOD may play a role in alleviating IR and inflammation with the modulating effect on microbiota in HFD-fed mice. Our findings could facilitate the development of AOD as a bioactive nutraceutical and more stable alternative to AST.

Hydrophilic Astaxanthin: PEGylated Astaxanthin Fights Diabetes by Enhancing the Solubility and Oral Absorbability

To develop hydrophilic astaxanthin with significantly enhanced solubility and stability, astaxanthin polyethylene glycol succinate (APGS) was synthesized by esterification of an astaxanthin succinate diester with polyethylene glycol 1000. The chemical structure of the hydrophilic derivative was confirmed by ¹H nuclear magnetic resonance and mass spectra. APGS showed better solubility than free astaxanthin in water and enhanced bioavailability compared to that of free astaxanthin. Additionally, testing the effects on diabetes and inflammation in a high-fat- and high-sucrose-diet-induced insulin-resistant mouse model demonstrated its benefits, suggesting that APGS maintains the health-promoting properties of astaxanthin. These results suggest that APGS could be a better source of hydrophilic astaxanthin.