Comprehensive metabolomics of Philippine Stichopus cf. horrens reveals diverse classes of valuable small molecules for biomedical applications.

Stichopus cf. horrens is an economically important sea cucumber species in Southeast Asia due to their presumed nutritional and medicinal benefits. However, compared to other sea cucumbers such as Apostichopus japonicus, there are no biochemical studies on which compounds contribute to the purported bioactivities of S. cf. horrens. To address this, a high-throughput characterization of the global metabolite profile of the species was performed through LC-MS/MS experiments and utilizing open-access platforms such as GNPS, XCMS, and metaboAnalyst. Bioinformatics-based molecular networking and chemometrics revealed the abundance of phospholipids such as phosphatidylcholines (PCs), phosphatidylethanolamines (PEs), phosphatidylinositols (PIs), and phosphatidylserines (PSs) in the crude samples. Body wall extracts were observed to have higher levels of structural, diacylated PCs, while the viscera have higher relative abundance of single-tail PCs and PEs that could be involved in digestion via nutrient absorption and transport for sea cucumbers. PEs and sphingolipids could also be implicated in the ecological response and morphological transformations of S. cf. horrens in the presence of predatory and other environmental stress. Interestingly, terpenoid glycosides and saponins with reported anti-cancer benefits were significantly localized in the body wall. The sulfated alkanes and sterols present in S. cf. horrens bear similarity to known kairomones and other signaling molecules. All in all, the results provide a baseline metabolomic profile of S. cf. horrens that may further be used for comparative and exploratory studies and suggest the untapped potential of S. cf. horrens as a source of bioactive molecules.

Physicochemical and Biochemical Characterization of Collagen from Stichopus cf. horrens Tissues for Use as Stimuli-Responsive Thin Films.

The mutable collagenous tissue (MCT) of sea cucumber, with its ability to rapidly change its stiffness and extensibility in response to different environmental stress conditions, serves as inspiration for the design of new smart functional biomaterials. Collagen, extracted from the body wall of Stichopus cf. horrens, a species commonly found in the Philippines, was characterized for its suitability as stimuli-responsive films. Protein BLAST search showed the presence of sequences commonly found in type VII and IX collagen, suggesting that Stichopus horrens collagen is heterotypic. The maximum transition temperature recorded was 56.0 ± 2 °C, which is higher than those of other known sources of marine collagen. This suggests that S. horrens collagen has better thermal stability and durability. Collagen-based thin films were then prepared, and atomic force microscopy (AFM) imaging showed the visible collagen network comprising the films. The thin films were subjected to thermomechanical analysis with degradation starting at >175 °C. At 100-150 °C, the collagen-based films apparently lose their translucency due to the removal of moisture. Upon exposure to ambient temperature, instead of degrading, the films were able to revert to the original state due to the readsorption of moisture. This study is a demonstration of a smart biomaterial developed from S. cf. horrens collagen with potential applications in food, pharmaceutical, biomedical, and other collagen-based research.

Diaporthe/Phomopsis longicolla degrades an array of bisphenol analogues with secreted laccase.

With recent initiatives to ban bisphenol A (BPA) in certain commercial products, manufacturers shifted to the production and use of BPA analogues. However, some of these BPA alternatives still possess endocrine disruptive activities. Many fungal enzymes are known to biodegrade phenolic compounds, such as BPA. However, the activity of these enzymes on BPA analogues remains unexplored. This study reports a secreted laccase from the endophytic fungus Diaporthe longicolla capable of degrading an impressive range of bisphenol analogues. The secreted crude enzymes are optimally active at pH 5 from 39 °C to 60 °C, efficiently degrading BPA as well as BPA analogues BPB, BPC, BPE and BPF. A purified form of laccase was identified from the crude fungal extract using FPLC and peptide sequencing. Furthermore, BPA induced the expression of this D. longicolla laccase gene. Overall, this paper demonstrated that the crude laccase enzyme from D. longicolla metabolizes BPA and select analogues, implicating the potential role of this fungus to remove environmental bisphenols.