A first glance into the nutritional properties of the sea cucumber Parastichopus regalis from the Mediterranean Sea (SE Spain)

How Biological Activity in Sea Cucumbers Changes as a Function of Species and Tissue

Biological activity and bioactive compound content in sea cucumbers was assessed, considering Parastichopus regalis, Holothuria mammata, Holothuria forskali, and Holothuria arguinensis as species and intestine, muscle band, respiratory tree, body wall, and gonads as tissues. P. regalis had the lowest content in phenolic compounds and antioxidant activity in contrast to Holothuria species. In the respiratory tree, the highest phenolic concentration was recorded in H. arguinensis, 76.4 ± 1.2 mg GAE/100 g dw vs. 21.0-49.0 mg GAE/100 g dw in the other species. H. arguinensis had the highest DPPH and FRAP results in the gonads, 13.6 ± 0.7 mg AAE/100 g dw vs. 2.6-3.5 mg AAE/100 g dw and 27.1 ± 0.3 μmol Fe2+/g dw vs. 8.0-15.9 μmol Fe2+/g dw, respectively. Overall, P. regalis biomass presented the highest anti-inflammatory activity levels and H. arguinensis the lowest anti-inflammatory levels. The respiratory tree was the most anti-inflammatory (measured by the inhibition of cyclooxygenase-2, COX-2) tissue in H. mammata and H. forskali (also the muscle band in this case), 76.3 ± 6.3% and 59.5 ± 3.6% COX-2 inhibition in 1 mg/mL aqueous extracts, respectively. The results demonstrated a variable bioactive potential and advantage in targeting antioxidant properties in the muscle band and anti-inflammatory activity in the respiratory tree, which may constitute a starting point for a biorefinery approach envisaging multiple applications.

The Effect of Ultrasound on the Rehydration Characteristics of Semi-Dried Salted Apostichopus japonicus

To effectively shorten the rehydration time of Apostichopus japonicus and reduce the nutrient loss during the rehydration process, an ultrasound-assisted rehydration method was adopted to rehydrate semi-dry salted A. japonicus in this study. The effects of different ultrasonic powers, temperatures, and times on the rehydration characteristics, textural characteristics, and sensory quality of the semi-dry salted A. japonicus were studied. Box-Behnken response surface analysis was used to study the influence of the interactions among the three factors on the rehydration ratio of the semi-dry salted A. japonicus, and a quadratic multinomic regression model was established to predict the optimal rehydration ratio. The results showed that ultrasound could change the structure of semi-dry salted A. japonicus and form a spatial network structure, thereby improving its water absorption capacity and reducing rehydration time. The optimal rehydration effect could be obtained when the ultrasonic power was 400 W, the ultrasonic temperature was 50 °C, and the ultrasonic time was 83 min. Ultrasonic power, ultrasonic time, and ultrasonic temperature influenced the rehydration ratio of the semi-dry salted A. japonicus. Under the optimal rehydration conditions in this study, the rehydration ratio of semi-dry salted A. japonicus obtained by the test was 2.103, which was consistent with the value predicted by the Box-Behnken response surface method.

UHPLC-MS/MS metabolomics analysis of sea cucumber (Apostichopus japonicus) processed using different methods

The effects of different processing methods on the nutritional components of sea cucumber (Apostichopus japonicus) are of concern to consumers who select sea cucumber products. This study employed liquid chromatography tandem mass spectrometry to examine the metabolites in fresh, unsoaked salted, soaked salted, and instant sea cucumber body wall samples sourced from Dalian, China. Metabolites were evaluated utilizing partial least squares discriminant analysis (PLS-DA) and subsequently subjected to KEGG metabolic pathway analysis for further investigation. PLS-DA effectively discriminated the body wall metabolites of sea cucumbers obtained via various processing techniques. The differential metabolites identified predominantly encompassed amino acids, lipids, and carbohydrates. Subsequent KEGG metabolic pathway analysis demonstrated a significant association between lipid, carbohydrate, and amino acid metabolism and the specific processing methods employed. The assessment of nutritional differences corresponding to the various A. japonicus processing methods was conducted. The findings of this study can assist in the choice of sea cucumber products and the selection of suitable processing methods.

Sea cucumber-derived compounds for treatment of dyslipidemia: A review

Dyslipidemias are disorders of plasma levels of lipids, such as elevated levels of total cholesterol and triglyceride, that are associated with various human diseases including cardiovascular disease (CVD) and non-alcoholic fatty liver disease (NAFLD). Statins are the first-line drugs for treatment of dyslipidemia. However, a substantial proportion of patients cannot reach the recommended LDL-c level even with the highest tolerated doses of statins, and there is no available drug specifically for NAFLD therapy. Sea cucumbers are one of the widely distributed invertebrates, and are an important resource of food and medicine. Sea cucumbers have many valuable nutrients including saponins, fatty acids, phospholipids, cerebrosides, sulfated polysaccharides, as well as proteins and peptides. In recent years, these natural products derived from sea cucumbers have attracted attentions for treatment of CVD and NAFLD because of their lipid-lowering effect and low toxicity. However, the hypolipidemic mechanisms of action and the structure-activity relationship of these bioactive components have not been well-documented in literature. This review article summarizes the signaling pathways and the potential structure-activity relationship of sea cucumber-derived bioactive compounds including saponins, lipids, carbohydrates as well as peptides and proteins. This article will provide information useful for the development of sea cucumber-derived lipid-lowering compounds as well as for investigation of hypolipidemic compounds that are derived from other natural resources.

Comprehensive proteomic analysis of sea cucumbers (Stichopus japonicus) in thermal processing by HPLC-MS/MS

Thermal processing is the most frequently adopted processing technology for sea cucumbers, which can significantly affect their protein composition. In this paper, three thermal processing methods high pressure steaming (HPS), atmospheric pressure boiling (APB), and atmospheric pressure steaming (APS) were adopted and protein compositions of both body walls and cooking liquors by thermal processing stichopus japonicus were systematically analysis by proteomic strategy. The total proteins loss rates of body walls were 11.6%, 13.0%, and 14.8% for HPS, APS, and APB methods, respectively. However, the main types of protein composition were retained. Similar mechanisms of protein loss may exist even if different thermal processing were applied. The most frequent hydrolysis sites in thermal processing were phenylalanine, leucine, asparagine, and tyrosine at both C and N terminals. This study provides theoretical guidance for optimizing the industry thermal processing of sea cucumbers.

Arenga westerhoutii Griff.: bioactive constituents, nutraceuticals, antioxidant and anti-diabetic potential of stem extract and an insight into molecular docking analysis

Herein, we reported a systematic scientific study of Arenga westerhoutii Griff. by evaluating its bioactive components, nutraceuticals, antioxidant and anti-diabetic properties. Three major bioactive compounds were identified using HPLC and HRMS. Quantification of the components through HPLC yielded the presence of 75.67 ± 0.05, 38.19 ± 0.10 and 13.11 ± 0.02 µg/mL of chlorogenic acid, ferulic acid and epicatechin respectively in 1 mg/ml of the extract. 50% MeOH hydro-alcoholic extract was found to show lowest IC₅₀ value in both in-vitro antioxidant (IC₅₀ = 2.925 ± 0.12 µg/mL, DPPH assay) and anti-diabetic assays (IC₅₀ = 18.03 ± 0.18 µg/mL, α-glucosidase assay). Further analysis by molecular docking study suggested the interaction of components towards α-glucosidase enzyme.

Occurrence and patterns of nutritional traits and polycyclic aromatic hydrocarbons (PAHs) in sea cucumber (Holothuria polii) tissues: benefits and risk for human health

Objectives

The paper evaluated the benefit and risk for human health associated with consumption of sea cucumber H. polii from Italian coasts (Central Mediterranean Sea).

Materials and Methods

body wall-BW, internal tunic-ITu, muscle bands-MB, alimentary canal-AC, gonad-Gd and respiratory tree-RT of H. polii were analyzed for proximate composition. Moreover, aminoacids, fatty acids and polycyclic aromatic hydrocarbons (PAHs) were determined with HPLC UV/Vis, GC-FID and GC-MS, respectively.

Results

Differences in the contents of Total Aminoacids (TAA) occurred based on tissue and sex, with AC and MB of female and Gd of male showing higher contents (range 47.8 -60.2 g/kg ww). Glycine and glutamic acid were the most abundant. Polyunsaturated (PUFA) was the major class of fatty acids and Arachidonic and Eicosapentaenoic (EPA) acids were the predominant PUFA. n-3 PUFA showed higher content in Gd, AC and RT indicating a higher quality. A favorable n-3/n-6 in the range 1.04-1.67 was observed. PAHs showed values ranged from 23 to 207 µg/kg ww with the highest levels in Gd-AC tissues and the lower in BW. Benzo[a]Pyrene, the most toxic compound, was detected in all tissues, of both sexes, at levels of 1.5-18 µg/Kg ww.

Conclusion

All tissues of H. polii, although with differences among them, are valuable food and can contribute for a healthy diet. Excess Cancer risk (CR) values for Gd and AC tissues, were above the considerable CR threshold of one in ten thousand established by USEPA, for high ingestion rate of these seafood.