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The detailed chemical investigations of the South China Sea soft corals Sinularia tumulosa and Sinularia depressa, yielded two new compounds, namely tumulosterol A (1) and 11'-hydroxy-α-tocopherylquinone (3), along with four related known ones (2, 5–7). Their structures were determined by extensive spectroscopic analysis and comparison with the spectral data previously reported in the literature. In bioassays, compound 1 displayed significant cytotoxic effects against H1975 and MDA-MB-231 cells with IC50 values of 6.0 and 6.3 µM, respectively. In addition, compound 3 exhibited interesting inhibitory effect on lipopolysaccharide (LPS)-induced inflammatory responses in RAW264.7 cells with IC50 value of 9.5 µM. [ABSTRACT FROM AUTHOR]

Nanolobatone A, featuring an unprecedented tricyclo[10.3.0.01,2]pentadecane carbon skeleton, along with four new polyoxygenated and four unusual endoperoxide‐bridged casbane‐type diterpenoids were isolated from the Hainan soft coral Sinularia nanolobata. The structures of the new compounds were established by extensive spectroscopic analysis, X‐ray diffraction analysis, and time‐dependent density functional theory/electronic circular dichroism calculations. A plausible biosynthetic pathway of new isolates was proposed. Bioassays revealed that nanolobatone A showed weak antibacterial activity against the Gram‐positive bacteria Streptococcus pyogenes. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome (mitogenome) of the soft coral Sinularia acuta Manuputty and van Ofwegen, 2007 was sequenced and annotated using Illumina next-generation sequencing (NGS). The mitogenome of S. acuta was 18,730 bp in length and consisted of 14 protein-coding genes (PCGs), two ribosomal RNA genes (rRNA), and only one transfer RNA gene (tRNA-Met). The base composition was 30.18% A, 16.46% C, 19.35% G, and 34.00% T, with a total A + T content of 64.19%. The phylogenetic analysis demonstrated a close evolutionary relationship among Sinularia acuta, Sinularia penghuensis, and Sinularia maxima. [ABSTRACT FROM AUTHOR]

Soft corals are zooxanthellate sessile animals supporting various organisms in coral reefs. However, their populations are threatened by the impacts of ocean warming. Under thermal stress conditions, soft corals may experience mild to severe bleaching which may lead to death. Understanding soft coral bleaching responses highlights the importance in predicting how populations and diversity may be affected by changing climate scenarios. In this study, we examined the bleaching responses of the three dominant soft coral genera (Lobophytum, n = 1318; Sarcophyton, n = 116; Sinularia, n = 639 colonies) in the Bolinao-Anda Reef Complex (BARC), Pangasinan, north-western Philippines during the 2020 thermal stress event in terms of genus and colony size susceptibility, and zooxanthellae density. Degree heating week (DHW) data from 1986–2020 were obtained using remotely sensed data to determine thermal anomalies in the study sites. The maximum DHW (6.3) in 2020 occurred between July–August while bleaching surveys were done during October of the same year. The percentage of bleached portions in each colony was used to determine bleaching category: no bleaching (0%), moderately bleached (1–50%) and heavily bleached (>50%). Quantification of bleaching prevalence and susceptibility of colony sizes were determined by colony count and mean diameter measurements taken from quadrat photographs in October 2020. Haphazard tissue collection (∼3 cm) in each colony of three soft coral genera per bleaching category was done to quantify zooxanthellae density. Results showed that Lobophytum colonies had the lowest bleaching prevalence (41%), followed by Sinularia (66%) and Sarcophyton (78%). All colony size classes of the three genera were susceptible to bleaching. However, smaller colonies of Lobophytum (<15 cm), Sarcophyton (<5 cm) and Sinularia (<5 cm) showed less susceptibility than large colonies. Zooxanthellae density was significantly reduced in moderately and heavily bleached colonies. The results of this study highlight that bleaching susceptibility is genus specific, with Sarcophyton and Sinularia being more susceptible to bleaching than Lobophytum. Smaller colonies seemed to be less susceptible to bleaching than large-sized soft corals suggesting a differential thermal stress response. Spatial variations in bleaching prevalence were also found among reef sites with varying environmental conditions and thermal stress histories. This work provided initial observations on how bleaching affects soft corals. Further studies on soft coral community recovery are recommended to fully understand how these organisms perform after thermal stress events. [ABSTRACT FROM AUTHOR]

Extending our knowledge about the bleaching and recovery processes in octocorals can offer valuable insights to predict future reef responses to continuing climate change. The octocoral Sinularia heterospiculata was exposed to a heat stress (32°C) for 2 days and then recovered within 205 days. The coral's response was assessed by measuring total lipids, chlorophylls , carotenoids, and relative endosymbiont density. During the bleaching period, the coral lost half of its dinoflagellate symbionts; during the recovery period, it could completely restore their population. Photosynthetic activity of dinoflagellate symbionts was reduced after 1 week of recovery. However, the level of lipids was stable. The contents of chlorophyll b after the 2-day bleaching period increased relative to their proportion in the endosymbionts, which may be associated with the chlorophyll repackaging and absorption of more light. The content of carotenoids increases, which is probably associated with the complementary function of carotenoids as antioxidants. [ABSTRACT FROM AUTHOR]

Soft corals are well-known as excellent sources of marine-derived natural products. Among them, members of the genera Sarcophyton, Sinularia, and Lobophytum are especially attractive targets for marine natural product research. In this review, we reported the marine-derived natural products called cembranoids isolated from soft corals, including the genera Sarcophyton, Sinularia, and Lobophytum. Here, we reviewed 72 reports published between 2016 and 2020, comprising 360 compounds, of which 260 are new compounds and 100 are previously known compounds with newly recognized activities. The novelty of the organic molecules and their relevant biological activities, delivered by the year of publication, are presented. Among the genera presented in this report, Sarcophyton spp. produce the most cembranoid diterpenes; thus, they are considered as the most important soft corals for marine natural product research. Cembranoids display diverse biological activities, including anti-cancer, anti-bacterial, and anti-inflammatory. As cembranoids have been credited with a broad range of biological activities, they present a huge potential for the development of various drugs with potential health and ecological benefits. [ABSTRACT FROM AUTHOR]

Aim: Spinal cord traumas have become a serious health problem with the increase in the ageing population in society. The present study aimed to show the anti-inflammatory activity of methylprednisolone and sinularia administered following spinal cord trauma. Materials and Methods: Sea corals are widely found on earth. Sinularia is one of the 17 known active substances of sinularia flexibilis, and several studies have been conducted on its anti-inflammatory, anti-oedema and cytotoxic effects. Despite the recent scientific studies, discussions continue as there are no effective treatment methods in use apart from methylprednisolone; however, the test animals received methylprednisolone treatment to compareits effects with those of sinularia, a secondary active ingredient of s. flexibilis. Results: Paired comparisons for serum IL-1β and tissue TNF-α were made with Dunn's test. When serum IL-1β and tissue TNF-α levels were evaluated, a significant difference was detected in the group taking sinularia treatment compared to the trauma group Sinularia treatment was more efficient on different cytokines and compared to methylprednisolone treatment used routinely, it significantly affected both IL-1β level and TNF-α levels in serum Conclusion: Anti-edematous, cytotoxic and anti-inflammatory effects of sinularia have been shown in our study. Sinularia, which has no known harmful effect on the human body according to the literature, may be clinically used in the future; however, more detailed and supportive experimental studies should be conducted on the subject. [ABSTRACT FROM AUTHOR]

Chemical examination of the octocoral Sinularia humilis, collected in the waters of Taiwan, led to the isolation of S8 (1). Its structure was determined by a single-crystal x-ray diffraction analysis and this is the first time that S8 has been reported from a marine invertebrate. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome of Sinularia penghuensis was sequenced and analyzed using next-generation sequencing. The present mitochondrial genome was 18730 bp in length, containing 14 protein-coding genes (PCGs) (cox1-cox3.nad1-nad6, nad4L, atp6, atp8, cytb, and MutS), two ribosomal RNA genes (rRNAs) (12S and 16S), and one transfer RNA gene (Met-tRNA). The phylogenetic analysis of family Alcyoniidae revealed that S. penghuensis and Sinularia maxima cluster together. Five species in Sinularia reveals high identity in mitogenome sequences that the lowest variable sites (SNPs) were found between S. penghuensis and S. maxima. [ABSTRACT FROM AUTHOR]

Two new steroids, ximaosteroid E ( 1 ) and ximaosteroid F ( 2 ), along with two known related compounds ( 3 and 4 ), were isolated from the Chinese soft coral Sinularia sp . Notably, 1 possesses an uncommon dihydrofuran group. Their structures were established from extensive spectroscopic analyses and comparisons of their spectral data with those reported in the literature. The absolute configuration of 2 was determined by applying the modified Mosher’s method. In bioassay, compounds 1 , 2 , and 4 showed significant cytotoxicity against the HL-60 tumor cell line with IC 50 values of 1.79, 4.03 and 0.69 μM, respectively. [ABSTRACT FROM AUTHOR]

Herein, we provide observation on the ecological relationships between the hydrozoan species Pteroclava krempfi and three alcyonacean genera: Lobophytum, Sarcophyton and Sinularia from protected and exposed reef habitats in the Maldives. The associations were found to be widespread in the investigated area with both an overall and taxon-specific symbiosis prevalence higher in the exposed reef sites. Pteroclava krempfi most frequently occurred with Lobophytum, followed by Sinularia and Sarcophyton. The prevalence of P. krempfi with soft corals was also positively correlated to percent host cover, which was higher in the outer reef sites, suggesting a host-reliant relationship for the hydrozoan. However, the nature of these relationships, as as well as the factors that drive their establishment, requires further investigation. The widespread degradation of coral reef ecosystems endangers the existence of many poorly understood, but intimate relationships that often go unrecognized. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome (mitogenome) of the soft coral Sinularia acuta Manuputty and van Ofwegen, 2007 was sequenced and annotated using Illumina next-generation sequencing (NGS). The mitogenome of S. acuta was 18,730 bp in length and consisted of 14 protein-coding genes (PCGs), two ribosomal RNA genes (rRNA), and only one transfer RNA gene ( tRNA-Met ). The base composition was 30.18% A, 16.46% C, 19.35% G, and 34.00% T, with a total A + T content of 64.19%. The phylogenetic analysis demonstrated a close evolutionary relationship among Sinularia acuta , Sinularia penghuensis , and Sinularia maxima ., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2023 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)

Two new cubitanoids, nanoculones A and B (1 and 2), and three new cembranoids, nanolobols A-C (3-5), as well as six known compounds, calyculone I (6), sinulariuol A (7), sinulariols C, D, H, and J (8-11), were isolated from the soft coral Sinularia nanolobata, collected off the coast of the eastern region of Taiwan. Their structures were elucidated on the basis of extensive spectroscopic analysis. Cytotoxicity of compounds 1-11 was evaluated. The nitric oxide (NO) inhibitory activity of selected compounds was further measured by assay of lipopolysaccharide (LPS)-stimulated NO production in activated RAW264.7 cells. The results showed that none of 1-11 exhibited cytotoxicity against the tested cancer cell lines, whereas compound 8 was found to significantly reduce NO production. [ABSTRACT FROM AUTHOR]

Three cadinane-type sesquiterpenoids, endoperoxide ( 1) and hydroperoxides ( 2, 3) together with three known sesquiterpenoids ( 4- 6) were isolated from an Okinawan soft coral, Sinularia species. Structures of these isolates were elucidated by spectroscopic analyses (NMR, IR and MS) and molecular modeling. In addition, the isolates 1- 3 as new compounds were examined for biological activities, resulting that they have antibacterial activity and weak cytotoxicity against HCT116 cells as well as anti-inflammatory effect on LPS/IFN-γ-stimulated RAW 264.7 macrophage cells. [ABSTRACT FROM AUTHOR]

Bioassay-guided fractionation of the marine sponge Lendenfeldia dendyi and the soft coral Sinularia dura resulted in the isolation of five polybrominated diphenyl ethers ( 1-5). The structures of the isolated compounds were determined using spectroscopic methods (1D and 2D NMR) and HRMS analyses. The absolute structures of compounds 1 and 2 were confirmed by X-ray analysis. Antimicrobial testing of the isolated compounds along with the acetylated derivative of compound 2 ( 2a) indicated that they displayed a significant and selective activity against methicillin-resistant Staphylococcus aureus (MRSa) with IC values of <0.04-1.18 µM. The antimalarial and antileishmanial activities of the isolated compounds were also evaluated. [ABSTRACT FROM AUTHOR]

Six new casbane diterpenoids, sinularcasbanes G-L ( 1- 6, resp.) were isolated from the soft coral Sinularia sp. Their structures were established by extensive spectroscopic analyses, especially 2D-NMR and HR-ESI-MS. The configuration was confirmed by CD analyses and by comparison with data reported in the literature. The compounds were evaluated for cytotoxicity against ten human cancer cell lines (H1975, U937, K562, BGC823, MOLT-4, MCF-7, A549, HeLa, HL60, and Huh-7) and showed no activity. [ABSTRACT FROM AUTHOR]

The mass coral bleaching event in South East Asian countries in 2010 caused severe damage to reef dwellers on the coast of the Andaman Sea and the Gulf of Thailand. Bleaching is a process where the symbiosis between corals and zooxanthellae (dinoflagellates of the genus Symbiodinium) breaks down. The symbiosis between Symbiodinium and corals is essential to the productivity, survival and success of corals. Symbiodinium associated with coral hosts is classified into six genetically distinct clades based on nuclear ribosomal DNA and partial chloroplast large subunit rDNA. Each clade possesses unique environmental, ecological and geographic variations, influencing the resilience of corals to elevated temperatures and bleaching. This study was the first field observation of changes in Symbiodinium communities in the Gulf of Thailand over two years including a natural bleaching event from late April to June, 2010. Phylogenetic clades and diversity of Symbiodinium inhabiting soft corals of the genus Sinularia were investigated using the analysis of chloroplast gene sequence variation at the ribosomal large subunit 23S Domain V. A total of 69 Sinularia spp. samples were obtained from two sampling sites off Jorake and Juang Islands (Sattahip, Chonburi Province) during two sampling periods: before (November 2008-January 2010, n??45) and after (November 2010, n??24) the 2010 coral bleaching event. The results revealed a significant change in the Symbiodinium community after the bleaching event. Before bleaching, most of Symbiodinium clade D was detected from Jorake Island while clade C was dominant in the Juang Islands. In contrast, after bleaching, only clade D was identified from both sampling sites. [ABSTRACT FROM AUTHOR]

Two novel chlorine-containing cembranoids, chlorofurancembranoids A (1) and B (2), were isolated from an octocoral identified as Sinularia sp. The structures of 1 and 2 were elucidated using spectroscopic methods, and the absolute configuration of 1 was further confirmed by single-crystal X-ray diffraction analysis. Cembranoid 2 showed cytotoxicity towards human promyelocytic leukemia HL-60 cells, with an IC 50 value of 3.67 μM. [Display omitted] [ABSTRACT FROM AUTHOR]

The application of DNA barcoding to anthozoan cnidarians has been hindered by their slow rates of mitochondrial gene evolution and the failure to identify alternative molecular markers that distinguish species reliably. Among octocorals, however, multilocus barcodes can distinguish up to 70 % of morphospecies, thereby facilitating the identification of species that are ecologically important but still very poorly known taxonomically. We tested the ability of these imperfect DNA barcodes to estimate species richness in a biodiversity survey of the shallow-water octocoral fauna of Palau using multilocus ( COI, mtMutS, 28S rDNA) sequences obtained from 305 specimens representing 38 genera of octocorals. Numbers and identities of species were estimated independently (1) by a taxonomic expert using morphological criteria and (2) by assigning sequences to molecular operational taxonomic units (MOTUs) using predefined genetic distance thresholds. Estimated numbers of MOTUs ranged from 73 to 128 depending on the barcode and distance threshold applied, bracketing the estimated number of 118 morphospecies. Concordance between morphospecies identifications and MOTUs ranged from 71 to 75 % and differed little among barcodes. For the speciose and ecologically dominant genus Sinularia, however, we were able to identify 95 % of specimens correctly simply by comparing mtMutS sequences and in situ photographs of colonies to an existing vouchered database. Because we lack a clear understanding of species boundaries in most of these taxa, numbers of morphospecies and MOTUs are both estimates of the true species diversity, and we cannot currently determine which is more accurate. Our results suggest, however, that the two methods provide comparable estimates of species richness for shallow-water Indo-Pacific octocorals. Use of molecular barcodes in biodiversity surveys will facilitate comparisons of species richness and composition among localities and over time, data that do not currently exist for any octocoral community. [ABSTRACT FROM AUTHOR]

[Display omitted] A novel cembranoid, (1 R ,7 R ,8 R ,11 R ,12 R)-7,8:11,12-bisepoxycembrene A (1), was isolated from an octocoral Sinularia sp. The structure of 1 was elucidated using spectroscopic methods, and its absolute configuration was confirmed by a single-crystal X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

Abstract: A novel norcembranoidal diterpene, sinulanorcembranolide A (1), which was found to possess a new carbon skeleton, was isolated from an octocoral identified as Sinularia gaweli. The structure of 1 was elucidated by spectroscopic methods. Sinulanorcembranolide A (1) was proven to be the first norcembranoidal diterpene with carbon–carbon linages between C-5/13 and C-7/12. A plausible biosynthetic pathway of 1 was proposed. [Copyright &y& Elsevier]

Abstract: The soft coral Sinularia flexibilis is currently considered as a suitable candidate for aquaculture. This soft coral is commonly traded for marine aquariums, is used in reef restoration efforts, as well as in the bioprospecting of marine natural products. The production of this coral under controlled laboratory conditions may be the best option for a sustainable and continuous supply of its biomass. It is known that the fragmentation of corals harboring photosymbiotic unicellular dinoflagellates of genus Symbiodinium, commonly termed zooxanthellae, can be influenced by light, as the photosynthetic performance of zooxanthellae can affect coral physiology and growth. This study aimed to investigate the effect of different light intensities on the photobiology of S. flexibilis following ex situ fragmentation. S. flexibilis mother colonies were fragmented after being acclimated for 5months to a photoperiod of 12h light with an irradiance of 120μmolquantam−2 s−1. Fragments were then distributed by three light treatments (50, 80 and 120μmolquantam−2 s−1) for monitoring of their photosynthetic performance, photosynthetic and accessory pigment concentration, zooxanthellae density, and growth. No significant differences were recorded one month post-fragmentation on the maximum quantum yield of PSII (F v/F m), neither on zooxanthellae density, between fragmented corals placed under tested light intensities. However, zooxanthellae density significantly increased after 5months in fragments exposed to 50 and 80μmolquantam−2 s−1, while F v/F m and pigment concentration decreased under the highest light intensity (120μmolquantam−2 s−1). This study showed that the use of low light levels after fragmentation, in the absence of heterotrophic feeding, do not significantly affect coral growth. Moreover, light levels used after fragmentation should be adjusted according to the intended stocking time of produced coral fragments. [Copyright &y& Elsevier]

A new sterol, (22R,23R,24R)-5α,8α-epidioxy-22,23-methylene-24-methylcholest- 6,9(11)-dien-3β-ol (1), and two known sterols, (22R,23R,24R)-5α,8α-epidioxy-22,23-methylene-24-methylcholest-6-en-3β-ol (2) and 24-methylenecholestane-1α,3β,5α, 6β,11α-pentol (3), were isolated from the soft coral Sinularia gaweli. The structure of sterol 1 was established by spectroscopic methods and by comparison of the spectral data with those of known analogues. The cytotoxicity of sterols 1-3 towards various tumor cells is reported. [ABSTRACT FROM AUTHOR]

Six new casbane diterpenoids, named as sinularcasbanes A-F (1-6), along with six known analogues 7-12, were isolated from a South China Sea soft coral, Sinularia sp. The structures of the new compounds were elucidated by extensive spectroscopic analysis and by comparison with data reported in the literature. All compounds were evaluated for their cytotoxicity against selected cancer cell lines and the inhibition of lipopolysaccharide (LPS)-induced nitric oxide (NO) production in mouse peritoneal macrophages. [ABSTRACT FROM AUTHOR]

Two norcembranoidal diterpenes, 5-episinuleptolide acetate (1) and scabrolide D (2), were isolated from a Formosan octocoral identified as Sinularia sp. The structures of norcembranoids 1 and 2 were established by spectroscopic methods and by comparison of the spectral data with those of known analogues and 1 was proven to be a new natural product. Norcembranoid 1 was found to exhibit cytotoxicity toward a panel of tumor cells [ABSTRACT FROM AUTHOR]

Fatty acids (FAs) composition of eight zooxanthellate soft corals, Sinularia leptoclados, S. flexibilis, S. aff. deformis, S. lochmodes, S. cf. muralis, S. densa, S. notanda and S. cruciata collected in Van Phong Bay (Vietnam) were studied to identify possible origin of unsaturated FAs. The main FAs were 14:0, 16:0, 7-Me-16:1n-10, 16:1n-7, 16:2n-7, 18:0, 18:1n-9, 18:4n-3, 20:4n-6, 20:5n-3, 22:6n-3, 24:5n-6 and 24:6n-3. On the average, saturated, monounsaturated, and polyunsaturated FAs (PUFAs) contributed 35.6, 6.2 and 54.0% of total coral FAs, respectively. PUFAs of n-6 series predominated in all animals (n-6/n-3 > 1.6). The content of 20:4n-6 varied from 10.2 to 23.8%. The main n-3 PUFA was 18:4n-3 (on the average, 5.4%); the contribution of 20:5n-3 and 22:6n-3, typical PUFAs of marine organisms, was not more than 2.4 and 3.9%, respectively. In Sinularia, PUFAs were produced by endosymbiotic dinoflagellates (zooxanthellae) and the coral host tissue, or obtained with food. Zooxanthellae can be considered as the source of C16 PUFAs and 18:4n-3. The coral host synthesized 18:2n-7, 24:5n-6 and 24:6n-3 acids. The low content of 18:1n-7, saturated odd-chain FAs and saturated methyl-branched FAs indicated a negligible contribution of bacteria to total lipids of Sinularia. A comparison of the levels of diatom and dinoflagellate FA markers in coral and plankton lipids showed eukaryotic microalgae to play a secondary role in feeding of Sinularia. The high level of 20:4n-6 may be considered as an indicator of heterotrophic feeding of Sinularia. [ABSTRACT FROM PUBLISHER]

The methanol extract of a Sinularia sp., collected from Bowden Reef, Queensland, Australia, yielded ten natural products. These included the new nitrogenous diterpene (4R*,5R*,9S*,10R*,11Z)-4-methoxy-9-((dimethylamino)-methyl)-12,15-epoxy-11 (13)-en-decahydronaphthalen-16-ol (1), and the new lobane, (1R*,2R*,4S*,15E)-loba-8,10, 13(14),15(16)-tetraen-17,18-diol-17-acetate (2). Also isolated were two known cembranes, sarcophytol-B and (1E,3E,7E)-11,12-epoxycembratrien-15-ol, and six known lobanes, loba-8, 10,13(15)-triene-16,17,18-triol, 14,18-epoxyloba-8,10,13(15)-trien-17-ol, lobatrientriol, lobatrienolide, 14,17-epoxyloba-8,10,13(15)-trien-18-ol-18-acetate and (17R)-loba-8,10,13 (15)-trien-17,18-diol. Structures of the new compounds were elucidated through interpretation of spectra obtained after extensive NMR and MS investigations and comparison with literature values. The tumour cell growth inhibition potential of 1 and 2 along with loba-8,10,13(15)-triene-16,17,18-triol, 14,17-epoxyloba-8,10,13 (15)-trien-18-ol-18-acetate, lobatrienolide, (1E,3E,7E)-11,12-epoxycembratrien-15-ol and sarcophytol-B were assessed against three human tumour cell lines (SF-268, MCF-7 and H460). The lobanes and cembranes tested demonstrated 50% growth inhibition in the range 6.8-18.5 &mgr;M, with no selectivity, whilst 1 was less active (GI50 70-175 &mgr;M). [ABSTRACT FROM AUTHOR]

The article presents the study which examined two new species and a new record of the Genus sinularia (Octocorallia: Alcyonacea) that were discovered at the Penghu archipelago in Taiwan. The two new species are the Sinularia penghuensis sp. nov. and the S. wanannensis sp. nov. It claims that the Sinularia specie is a highly speciose genus among IndoPacific coral reefs octocorals. The species were examined through the use of scanning electron microscopy (SEM). The species were also compared with materials kept at the Zoological Museum, Department of Zoology, Tel Aviv University, Israel (ZMTAU) and the Netherlands Center for Biodiversity, Naturalis, Leiden, the Netherlands (RMNH).

Alcyonacean octocorals in tropical reefs are usually not considered as reef builders. Some Sinularia species, however, are capable of consolidating sclerites at the colony base to form spiculite. Nanwan Bay, southern Taiwan, features both fossilized and recently formed boulders composed of spiculite, thus demonstrating the role of Sinularia in contributing to the reef structure. Section radiography of an 18.5 kg spiculite boulder demonstrated a regular density banding of 3-6-mm intervals. Core survey indicated spiculite coverage of 25-30% on the live reef and of 30-40% on the uplifted boulders. Cores taken from living Sinularia revealed a distinct transition from discrete sclerites to compact spiculite and amorphous calcium carbonate cementing the sclerites. In the widespread S. gibberosa, sclerite formation appeared to start intracellularly, followed by a prolonged extracellular calcification process. At the calcification site, multiple sclerocytes formed expanded pseudopod-like membranes that interconnected, forming multicellular vesicles (MCVs) around the sclerites. The MCVs and the pseudopods disappeared at sclerite maturation, followed by degradation of the sclerocytes around the mature sclerites. At the colony base, granular vesicles were distributed among the sclerites, indicating a cementing process in progress. These findings suggest that colonies of Sinularia are able to cement sclerites and consolidate them at their base into spiculite, thus making them reef builders. [ABSTRACT FROM AUTHOR]

Abstract: Chemical analysis of the Indonesian soft coral Sinularia sp. (order Alcyonacea, family Alcyoniidae) afforded two known and three new C-4 norcembranoids, named chloroscabrolides A (3) and B (4) and prescabrolide (5). Chloroscabrolide A is a pentacyclic norcembranoid including an unprecedented THF-type ring to connect C-13 and C-15; furthermore, it is only the second chlorinated cembranoid derivative to be reported in the literature. The relative configuration of chloroscabrolide A has been established on the basis of a comparison between experimental 13C NMR data and DFT-calculated 13C NMR chemical shifts. All the isolated norcembranoids have been evaluated for iNOS protein inhibition. [Copyright &y& Elsevier]

A new species of the genus Sinularia, S. choui, featuring leptoclados-type clubs, is described and depicted from Singapore coral reefs. S. acuta Manuputty & Ofwegen, 2007, featuring similar clubs, is discussed. Three other species of this genus with such clubs are listed: S. maxima Verseveldt, 1971; S. molesta Tixier-Durivault, 1970 and S. verseveldti Ofwegen, 1996. S. polydactyla (Ehrenberg, 1834) is also listed. All these species are new zoogeographical records for Singapore. The total Sinularia citation fauna of Singapore currently comprises of 18 species. [ABSTRACT FROM AUTHOR]

The article presents a study on the identification of three new species of Lobophytum and Sinularia genera as a result of octocoral survey undertaken in Penghu Archipelago, Taiwan. The study collected 230 octocoral specimens in July 2006 and July 2009 through scuba diving. The study revealed the new species such as Lobophytum hsiehi sp. nov. which has no polyp sclerites, Sinularia daii sp. nov. which has large clubs, and Sinularia soongi sp. nov. with tentacle rods and polyps with collaret.

Two metabolites featuring norcembranoid diterpene skeleton have been isolated from chloroform extract of soft coral of the genus sinularia, which was collected from the southern coast of India. The structures of the metabolites were determined by 1D, 2D NMR spectroscopic data and HRESIMS data analysis. The compounds have shown moderate-to-high antimicrobial activities. The structure and the relative stereochemistry of the metabolite 1 have been determined by X-ray crystallography. [ABSTRACT FROM AUTHOR]

The resilience of Symbiodinium harboured by corals is dependent on the genetic diversity and extent of connectivity among reef populations. This study presents genetic analyses of Great Barrier Reef (GBR) populations of clade C Symbiodinium hosted by the alcyonacean coral, Sinularia flexibilis. Allelic variation at four newly developed microsatellite loci demonstrated that Symbiodinium populations are genetically differentiated at all spatial scales from 16 to 1,360 km (pairwise ΦST = 0.01-0.47, mean = 0.22); the only exception being two neighbouring populations in the Cairns region separated by 17 km. This indicates that gene flow is restricted for Symbiodinium C hosted by S. flexibilis on the GBR. Patterns of population structure reflect longshore circulation patterns and limited cross-shelf mixing, suggesting that passive transport by currents is the primary mechanism of dispersal in Symbiodinium types that are acquired horizontally. There was no correlation between the genetic structure of Symbiodinium populations and their host S. flexibilis, most likely because different factors affect the dispersal and recruitment of each partner in the symbiosis. The genetic diversity of these Symbiodinium reef populations is on average 1.5 times lower on inshore reefs than on offshore reefs. Lower inshore diversity may reflect the impact of recent bleaching events on Sinularia assemblages, which have been more widespread and severe on inshore reefs, but may also have been shaped by historical sea level fluctuations or recent migration patterns. [ABSTRACT FROM AUTHOR]

Sinularia polydactyla, an abundant Indo-Pacific soft coral species, exhibits biochemical phenotypic plasticity, prompting investigations into differences in mRNA diversity and complexity in response to predation stress. Changes in transcriptome complexity of S. polydactyla cDNA libraries were measured using reannealing rate assays that employ an informatics-based analysis of kinetic profiles. This method allows for quick, high-throughput analysis of sequence complexity and has been used to compare transcriptome-level differences in other marine invertebrates. Here, S. polydactyla colonies were transplanted between two sites exhibiting high and low predation levels. Statistically significant differences between bite scar counts found on different transplant groups suggest site-specific variation in predation. Changes in mRNA pool complexity were quantified to indicate shifts in secondary metabolite concentration between treatment groups. Examining the complexity of the mRNA pool in this soft coral is one of the first steps toward understanding the mechanisms of phenotypic plasticity at a biochemical and molecular level. [ABSTRACT FROM AUTHOR]

Abstract: Four novel cyclic peroxide-containing sesquiterpenes ( 1–4 ), with a γ-alkylidene-α-methyl-α,β-unsaturated γ-lactone moiety, have been isolated from a Formosan soft coral of the genus Sinularia. Their structures were elucidated mainly by extensive 1D and 2D NMR experiments. [Copyright &y& Elsevier]

The soft coral genus Sinularia is one of the most widely distributed soft corals. It constitutes a dominant portion of the biomass in the tropical reef environment. Sinularia elaborates a rich harvest of secondary metabolites including sesquiterpenes, diterpenes, polyhydroxylated steroids, and polyamine compounds. These metabolites were recently shown to possess a range of biological activities such as antimicrobial, anti-inflammatory, and cytotoxic activities. During the past decade, Sinularia has yielded many new structures with novel skeletons. Several of the previously published secondary metabolites have been reexamined for their pharmacological properties, and the results strongly support further investigations. The current article reviews the terpenoids of the soft coral genus Sinularia and their pharmacological significance. [ABSTRACT FROM AUTHOR]

We evaluated the role that demography may play in the formation of local aggregations ofSinularia flexibilis(Quoy&Gaimard, 1833), a soft coral that commonly dominates inshore coral reefs of the Great Barrier Reef (GBR), Australia. Two populations on inshore reefs of the Palm Islands were censused once a year for 3?years, starting 10 mo after the extensive bleaching mortality in early 1998. Larger colonies became more prevalent over time; mean colony size increasing by 35%, from 276 cm2 in 1998 to 373 cm2 in 2000. Growth rates were size dependent, with smaller colonies growing proportionally faster than larger colonies. Change in size relative to initial size indicated an expected mean annual growth of 128 cm2 for a 50-cm2 colony. Zero growth was predicted at 532±21cm2, with colonies larger than this likely to undergo fission or shrink. Forty-three percent of colonies were undergoing fission at any time at both localities. Most new colonies were produced by fission (70%,n=285), with the remainder produced by the recruitment of sexually produced larvae (19%) or by colony translocation (11%). The sexual and asexual recruitment rates were 0.24 and 1.0 recruits m-2 year?1, respectively. Opportunistic recruitment and rapid growth following disturbances are commonly assumed to be the mechanisms leading soft corals to dominate locally. In this study, these mechanisms operated more slowly than expected, with no net change in population size. [ABSTRACT FROM AUTHOR]

Coral polyps host intracellular symbiotic dinoflagellates (SD). The loss of SD (referred as bleaching) under stressful environmental conditions is the main reason of coral reef destruction, and therefore, intensively studied over the world. Lipids are the structural base of biomembranes and energy reserve of corals and are directly involved in the coral bleaching. In order to establish a relationship between coral tissue morphology, physiological processes and lipidome dynamics during bleaching, the soft coral Sinularia heterospiculata was exposed to experimental heat stress (33 °C) for 72 h. A chlorophyll content, structure of cells, the level of reactive oxygen species (ROS), and molecular species of storage and structural lipids were analyzed. After 24 h of heat exposure, the level of ROS-positive SD cells did not increase, but the host tissues lost a significant part of SD. The removal of SD cells by exocytosis were suggested. Exocytosis was presumed to prevail at earlier stages of the soft coral bleaching. Symbiophagosomes with degenerative SD were observed in the stressed coral host cells. After 24 h, the content of phosphatidylinositols, which involved in apoptosis and autophagy, was significantly decreased. The innate immune response was triggered, and SD were digested by the coral host. After 48 h, a degradation of SD chloroplasts and a decrease in the specific monogalactosyldiacylglycerol molecular species were detected that confirmed a disruption of lipid biosynthesis in chloroplasts. At the end of coral bleaching, the appearance of oxidized phosphatidylethanolamines, indicating damage to the host membranes, and the degradation of the coral tissues were simultaneously observed. Thus, a switch between dominant mechanisms of the SD loss during bleaching of S. heterospiculata was found and proved by certain variations of the lipidomic profile. Lipidomic parameters may become indicators of physiological processes occurring in the symbiotic coral organism and may be used for assessing anthropogenic or natural destructive effects on coral reefs. [Display omitted] • Lipid parameters can serve as indicators of processes occurring in stressed coral. • Content of prokaryotic monogalactosyldiacylglycerols pointed to zooxanthellae damages. • Phosphatidylinositol involved in apoptosis and autophagy was significantly decreased. • Oxidized phosphatidylethanolamines indicated on damages to the host cell membranes. [ABSTRACT FROM AUTHOR]

Marine organisms are recognized as a rich source of bioactive secondary metabolites. The remarkable abundance and diversity of bioactive small molecules isolated from soft corals displayed their essential role in drug discovery for human diseases. Sterols and terpenes, particularly cembranolides, 14-membered cyclic diterpene, demonstrated numerous biological activities, such as antitumor, antimicrobial, antiviral, antidiabetic, anti-osteoporosis and anti-inflammatory. Accordingly, continuous investigation of marine soft corals leads the way to discover a plentiful number of chemical diverse natural products with various biological potentials for prospective pharmaceutical industrial applications. Such review affords plenary inspection of the total secondary metabolites isolated from the Sinularia, from 2008 until 2020, besides their natural sources as well as bioactivities whenever possible., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Sinularia is one of the conspicuous soft coral species widely distributed in the world's oceans at a depth of about 12 m. Secondary metabolites from the genus Sinularia show great chemical diversity. More than 700 secondary metabolites have been reported to date, including terpenoids, norterpenoids, steroids/steroidal glycosides, and other types. They showed a broad range of potent biological activities. There were detailed reviews on the terpenoids from Sinularia in 2013, and now, it still plays a vital role in the innovation of lead compounds for drug development. The structures, names, and pharmacological activities of compounds isolated from the genus Sinularia from 2013 to March 2021 are summarized in this review. [ABSTRACT FROM AUTHOR]