effective-techniques-for-feeding-ex-situ-culture-brooding

Effective Techniques for the Feeding and <em>Ex Situ</em> Culture of a Brooding Scleractinian Coral, <em>Pocillopora acuta</em>

Climate change is affecting the survival, growth, and recruitment of corals globally, with large-scale shifts in abundance and community composition ...

National Museum of Marine Biology & Aquarium

Gorgonian corals are suffering continued decline in population and reproductive ability because of environmental changes. Cryopreservation can play an important role in ex situ conservation for these corals. In the present study, oocyte chilling sensitivity in the context of adenosine triphosphate (ATP) response in two gorgonian species (Junceella juncea and Junceella fragilis) and the effectiveness of cryoprotectants in protecting coral oocytes from chilling injury were studied in an attempt to develop protocols for their cryopreservation. Oocytes of two gorgonian corals were exposed to methanol (1 M, 2 M) and EG (1 M) at 5, 0 and -5 degree C for up to 216 hours, and ATP levels in oocytes were then determined. ATP levels decreased gradually with exposure time and 1M methanol was more effective in protecting oocytes from chilling injury than other cryoprotectant treatments tested. J. juncea oocytes were less sensitive to chilling than J. fragilis oocytes. This study provided useful information for development of cryopreservtion protocols for the two gorgonian coral oocytes.

Gorgonian coral (Junceella juncea and Junceella fragilis) oocyte chilling sensitivity in the context of adenosine triphosphate response (ATP).

Sea turtles are globally endangered and face daily anthropogenic threats, including pollution. However, there is a lack of ecotoxicological information on sea turtles, especially in the Asia-Pacific region. This study aims to determine pollutant levels of foraging green turtles (Chelonia mydas) in South China, including Hong Kong, Guangdong and Taiwan, as a basis for their conservation. Scute, liver and muscle tissues of stranded green turtles were analysed for levels of 17 trace elements and methylmercury (MeHg) (n = 86 for scute and n = 14 for liver) and polybrominated diphenyl ethers (PBDEs) (n = 11 for muscle and n = 13 for liver). Ten-fold higher levels of Pb, Ba, V and Tl and 40-fold greater Cd levels were measured in green turtle livers in South China relative to other studies conducted over 10 years ago. Measured PBDE levels were also 27-fold and 50-fold greater than those reported in Australia and Japan. These results warrant further investigation of potential toxicological risks to green turtles in South China and their source rookeries in Malaysia, Micronesia, Indonesia, Marshall Islands, Japan and Taiwan. Research should target monitoring pollutant levels in sea turtles within the West Pacific/Southeast Asia regional management unit spanning East Asia to Southeast Asia to fill in knowledge gaps, in particular in areas such as Thailand, Vietnam, Indonesia, Malaysia and the Philippines where less or no data is available and where foraging grounds of sea turtles have been identified.

Levels of trace elements, methylmercury and polybrominated diphenyl ethers in foraging green turtles in the South China region and their conservation implications.

Three new sesquiterpenoids (sinuketal (), sinulins A and B ( and )) and two new cembranoids (sinulins C and D ( and )), as well as eight known sesquiterpenoids () and eight known cembranoids (), were isolated from the Xisha soft coral  sp. Their structures were elucidated by extensive spectroscopic analysis. Compound  possesses an unprecedented isopropyl-branched bicyclo [6.3.0] undecane carbon skeleton with unique endoperoxide moiety, and a plausible biosynthetic pathway of it was postulated. According to the reported biological properties of endoperoxide, the antimalarial, cytotoxic, antiviral, and target inhibitory activities of  were tested. Compound  showed mild in vitro antimalarial activity against  3D7, weak cytotoxic activities toward Jurkat, MDA-MB-231, and U2OS cell lines, inhibitory effects against influenza A viruses H1N1 and PR8, as well as mild target inhibitory activity against acetylcholinesterase. The other compounds were evaluated for cytotoxicities against HeLa, HCT-116, and A549 tumor cell lines and target inhibitory activities against protein tyrosine phosphatase 1B (PTP1B). Compound  exhibited cytotoxicities against HeLa and HCT-116, and compounds , , and  showed mild target inhibitory activities against PTP1B.

Terpenoids from the Soft Coral  sp. Collected in Yongxing Island.

Submarine groundwater discharge (SGD) is the submarine seepage of all fluids from coastal sediments into the overlying coastal seas. It has been well documented that the SGD may contribute a great deal of allochthonous nutrients to the coastlines. It is, however, less known how much carbon enters the ocean via the SGD. Nutrients (NO, NO, NH, PO, SiO), alkalinity and dissolved inorganic carbon (DIC) in the submarine groundwater were measured at 20 locations around Taiwan for the first time. The total N/P/Si yields from the SGD in Taiwan are respectively 3.28 ± 2.3 × 10, 2.6 ± 1.8 × 10 and 1.89 ± 1.33 × 10 mol/km/a, compared with 9.5 ± 6.7 × 10 mol/km/a for alkalinity and 8.8 ± 6.2 × 10 mol/km/a for DIC. To compare with literature data, yields for the major estuary across the Taiwan Strait (Jiulong River) are comparable except for P which is extremely low. Primary production supported by these nutrient outflows is insufficient to compensate the DIC supplied by the SGD. As a result, the SGD helps making the coastal waters in Taiwan and Jiulong River heterotrophic.

Submarine Groundwater Discharge helps making nearshore waters heterotrophic.

We have conducted a long-term research on the Taiwanese soft coral , which resulted in many xenicane-type diterpenoids such as asterolaurins A-M from  coral tissues during the non-spawning period were isolated. Here, we report a new xenicane diterpenoid, asterolaurin N (), along with three known xenicane-type monocarbocyclic diterpenes [13-epi-9-desacetylxenicin (), xeniolide-B 9-acetate () and asterolaurin I ()] from  during the spawning period. The structures of the new secondary metabolite were established with an extensive spectroscopic analysis. The 1D and 2D nuclear magnetic resonance (NMR) data of the compounds were discussed. We discovered that the C-15 of  contains two methyl groups on a carbon bearing an acetyl group, which has not been reported previously. In addition, Compounds , , and  showed selective cytotoxic activity against Molt 4, while  exhibited significant cytotoxicity against Molt 4, K562, Sup-T1 and U937 cell lines.

New secondary metabolite with cytotoxicity from spawning soft coral  in Taiwan.

Our continuous chemical study of a cultured octocoral  led to the isolation of four new briarane diterpenoids, briarenols Q-T (-). The structures of new metabolites - were established by spectroscopic methods, and compounds  and  were found to inhibit the generation of inducible nitric oxide synthase (iNOS) from RAW 264.7 stimulated by lipopolysaccharides (LPS).

Briarenols Q-T: Briaranes from A Cultured Octocoral  (Kükenthal, 1908).

 is proven to be a rich source of 3,8-cyclized cembranoids (briarane) with a bicyclo[8.4.0] carbon core. In the present study, four previously unreported briaranes, briarenols W-Z (-), along with solenolide A (), briarenolide M (), briaexcavatolide F (), and brianolide (), were isolated and characterized through spectroscopic analysis, and the absolute configuration of  was corroborated by a single-crystal x-ray diffraction analysis. Briaranes  and  were found to induce significant inflammatory activity in lipopolysaccharide (LPS)-induced RAW 264.7 mouse macrophage cells by enhancing the expression of the inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins.

Briarenols W-Z: Chlorine-Containing Polyoxygenated Briaranes from Octocoral  (Kükenthal, 1908).

Bladder cancer (BC) is a very common type of malignant cancer in men and new therapeutic strategies are urgently needed to reduce mortality. Several studies have demonstrated that Rhopaloic acid A (RA), a compound isolated from marine sponges, fights cancer but its potential anti-tumor effect on BC is still unknown.

Rhopaloic acid A induces apoptosis, autophagy and MAPK activation through ROS-mediated signaling in bladder cancer.

The ichthyofauna of continental islands is characterized by immigration through a land bridge due to fluctuating sea levels. Hainan Island is adjacent to the southern margin of mainland China and provides opportunities for understanding the origin and diversification of freshwater fishes. The aim of our study was to evaluate the level of genetic variation and phylogeographic structure of  on Hainan Island and mainland China, using mtDNA cyt  gene (1140 bp) and D-loop (926 bp), nuclear RAG1 gene (1506 bp), and 12 microsatellite loci. Mitochondrial phylogenetic analysis identified five major lineages according to the geographical distribution from different populations. We suggested that two dispersal events occurred: the population in the Changhua River migrated to the Red River (Lineage B), and the populations in the South Hainan region moved northwards to the North Hainan region. However, populations in Northwest Hainan Island dispersed to the populations around the Gulf of Tonkin (Lineage A1) and populations in Northeast Hainan Island dispersed to the populations in mainland China (Lineage A2). Our results indicated that the populations of  suffered a bottleneck event followed by a recent population expansion supported by the ABC analysis. We suggest that  populations were found mostly in the lowlands and a lack of suitable freshwater habitat in southern mainland China and Hainan during the Last Interglacial period, and then expansion occurred during the Last Glacial Maximum.

Article	Year
Gorgonian coral (Junceella juncea and Junceella fragilis) oocyte chilling sensitivity in the context of adenosine triphosphate response (ATP). Cryo letters\| PubMed ID: 21766143	2011
Levels of trace elements, methylmercury and polybrominated diphenyl ethers in foraging green turtles in the South China region and their conservation implications. Environmental pollution (Barking, Essex : 1987)\| PubMed ID: 29245147	2018
Terpenoids from the Soft Coral sp. Collected in Yongxing Island. Marine drugs\| PubMed ID: 29652789	2018
Submarine Groundwater Discharge helps making nearshore waters heterotrophic. Scientific reports\| PubMed ID: 30076335	2018
New secondary metabolite with cytotoxicity from spawning soft coral in Taiwan. Natural product research\| PubMed ID: 31364881	2021
Briarenols Q-T: Briaranes from A Cultured Octocoral (Kükenthal, 1908). Marine drugs\| PubMed ID: 32722176	2020
Briarenols W-Z: Chlorine-Containing Polyoxygenated Briaranes from Octocoral (Kükenthal, 1908). Marine drugs\| PubMed ID: 33572535	2021
Rhopaloic acid A induces apoptosis, autophagy and MAPK activation through ROS-mediated signaling in bladder cancer. Phytomedicine : international journal of phytotherapy and phytopharmacology\| PubMed ID: 34481340	2021
Multilocus Phylogeography and Population Genetic Analyses of Reveal Pleistocene Isolation Followed by High Gene Flow around the Gulf of Tonkin. Genes\| PubMed ID: 36292792	2022

Xuan-Ci Zhang

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