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Towards the sustainable development, optoelectronic devices with biodegradability and biocompatibility have been a desirable but challenging issue for years. In this study, an all-biomaterial random laser device based on all-marine elements has been demonstrated. Chlorophyll and blue coral skeletons serve as gain medium and scattering centers, respectively. The chlorophyll is derived from marine diatoms, which are ubiquitous in the ocean and set up an abundant source for the device. On the other hand, the coral skeletons with intrinsic nanorod structures can provide a strong optical confinement and feedback for laser action. The proposed design signifies the novel application of marine materials and represents a significant step for the development of bio-inspired photonics modules.

Recurrent thermal stress events and intensified precipitation alter the ocean environment resulting in the decline of coral populations. However, the influence of these changes on larval survival and settlement is not well understood. We examined the effect of salinity (15, 20, 25, 30, 35, and 40 ppt) and temperature (27 °C, 30 °C, and 33 °C) on settlement and survival of larvae of the octocoral, Heliopora coerulea. Larvae settled successfully at salinities from 25 to 30 ppt. On the other hand, larval survival and settlement decreased with increasing temperature. A combination of 25–35 ppt and 27–30 °C resulted in highest survival and settlement. These results indicate that early life stages of H. coerulea are negatively impacted by thermal stress but may be able to survive at reduced salinity. The wider tolerance range of H. coerulea larvae compared to most scleractinian larvae may thus contribute to the success of this coral on disturbed reef ecosystems.

Seven new diterpenes, helioporins A-G (1–7), have been isolated from the blue coral Heliopora coerulea . The structures determined by spectroscopic data and chemical conversions are related to the aglycons of pseudopterosins and seco-pseudopterosins, which are antiinflammatory glycosides from Caribbean gorgonians. Treatment of helioporin A ( a ) with TMSI/NaI followed by Na 2 S 2 O 3 gave helioporin E ( 5 ) and an unusual product ( 11 ) resulting from CC bond cleavage. Reaction of helioporin B ( 2 ) with Tf 2 O/C 5 H 2 NMe t -Bu 2 followed by catalytic reduction gave a cyclization product ( 14 ) which was identical with a compound derived from 5 . All helioporins were chemically correlated and their relative stereochemistry was related to that of the aglycon of pseudopterosin G ( 10 ). Helioporins A and B showed antiviral activity against HSV1 and C-G cytotoxicity against P388.

Zeatin, zeatin riboside, dihydrozeatin and isopentenyladenine have been isolated from green algae and blue coral along with two new cytokinins, characterized as 2-hydroxy-6-methylaminopurine and 2-hydroxy-1′methylzeatin.