Four New Briarane Diterpenoids from the Gorgonian Coral Junceella fragilis

Chemical investigation of the gorgonian coral Junceella fragilis, collected by scuba diving in Taiwan, resulted in the isolation of four new briarane‐type diterpenoids, frajunolides A–D ( 1 – 4 ), along with three known briaranes. Their structures were elucidated on the basis of spectroscopic studies, especially 1‐ and 2D‐NMR as well as HR‐MS experiments. The inhibitory effect of all isolated metabolites towards superoxide‐anion generation and elastase release by human neutrophils in response to formylmethionyl‐leucyl‐phenylalanine/dihydrocytochalasin B (FMLP/CB) was evaluated.     

Two furano-sesquiterpenes from the South China Sea Sponge Dysidea fragilis

A new sesquiterpene, ent-furodysin (1), has been isolated from the South China Sea Sponge Dysidea fragilis, along with a known sesqui-terpene, ent-furodysinin (2). The structure and relative stereochemistry of 1 and 2 were established by spectral analysis.     

Ten new antifouling briarane diterpenoids from the South China Sea gorgonian Junceella juncea

Ten new antifouling briarane diterpenoids, juncins R-ZI (1-10) were isolated from the South China Sea gorgonian coral Junceella juncea. The structures of these new compounds were established by extensive spectroscopic analysis, including 1D and 2D NMR data. Compounds 1-10 all showed potent antifouling activities against the larval settlement of barnacle Balanus amphitrite at nontoxic concentrations with EC₅₀ values of 0.004, 0.34, 2.65, 1.61, 3.77, 21.06, 0.004, 0.14, 1.47, and 0.51 μg mL⁻¹. The structure-activity relationship was discussed.     

Juncenolides H – K,New Briarane Diterpenoids from Junceella juncea

Chemical investigation of the Taiwanese gorgonian coral Junceella juncea resulted in the isolation of four new briarane‐type diterpenoids, juncenolides H, I, J, and K ( 1 – 4 ). Their structures were determined on the basis of spectroscopic analysis, especially 1‐ and 2D‐NMR. The inhibitory effects of compounds 1 – 4 on superoxide‐anion generation and elastase release by human neutrophils were evaluated.     

Identification of the polymorphisms in IFITM3 gene and their association in a Korean population with ulcerative colitis

Interferons play critical roles in tumor pathogenesis by controlling apoptosis and through cellular anti-proliferative and differentiation activities. Interferon inducible transmembrane protein (IFITM) family genes have been implicated in several cellular processes such as the homotypic cell adhesion functions of IFN and cellular anti-proliferative activities. Expression levels of IFITM genes have been found to be up-regulated in gastric cancer cells and colorectal tumors. IFITM3 (also known as 1-8U) is a member of the IFITM family, and has been described as a key player in specification of germ cell fate. IFITM3 was first isolated from a genetic screen aimed at identifying genes involved in acquisition of germ cell competence. It has been proposed that epiblast cells have the highest expression of IFITM3 initiated germ cell specification and that homotypic association can discriminate germ cells from their somatic neighbors. In an attempt to better understand the genetic influences of IFITM3 on ulcerative colitis, we have identified possible variation sites and single nucleotide polymorphisms (SNPs) through two exons and their boundary IFITM3 intron sequences including the ~2.1 kb promoter regions. To determine whether or not these IFITM3 SNPs are associated with susceptibility to ulcerative colitis, frequencies of the genotype and allele of IFITM3 polymorphisms were analyzed on genomic DNAs isolated from patients with ulcerative colitis and from healthy controls. We also investigated the haplotype frequencies constructed by these SNPs in both groups. In this study, we also showed that expression level of IFITM3 mRNA was significantly higher in tissues of the ileum and cecum of the digestive system. We identified a total of seven SNPs and multiple variation regions in the IFITM3 gene. The genotype frequency of the g.-204T>G polymorphism in patients with ulcerative colitis was significantly different from that of the control group. Our results strongly suggest that polymorphisms of the IFITM3 gene may be associated with susceptibility to ulcerative colitis.     

Juncenolide E,A New Briarane from Taiwanese Gorgonian Junceella Juncea

In addition to junceellolides B ( 3 ) and C ( 4 ), a new briarane, juncenolide E ( 1 ) has been isolated from the acetone extract of the red gorgonian Junceella juncea, collected on the southern coast of Taiwan. The structure of juncenolide E was determined by interpretation of MS, COSY, HMQC, HMBC and NOESY spectra.     

New briaranes from the octocorals Briareum excavatum (Briareidae) and Junceella fragilis (Ellisellidae)

Six 12-hydroxybriaranes, including four new diterpenoids, briaexcavatins I-L (1-4), and two known metabolites, excavatolides C (5) and E (6), have been isolated from the cultured scleraxonia Briareum excavatum. In addition, the gorgonian coral Junceella fragilis yielded a new chlorinated briarane, fragilide C (10). The structures of above compounds were determined by spectroscopic methods and the structures of 5 and 6 were further confirmed by X-ray data analysis for the first time. The absolute configuration of 6 was elucidated by chemical conversion. Some of these briaranes have displayed inhibitory effects on superoxide anion generation by human neutrophils.     

Bioactive Compounds from Ephedra fragilis: Extraction Optimization,Chemical Characterization,Antioxidant and AntiGlycation Activities

Response surface methodology (RSM) with a Box–Behnken design (BBD) was used to optimize the extraction of bioactive compounds from Ephedra fragilis. The results suggested that extraction with 61.93% ethanol at 44.43 °C for 15.84 h was the best solution for this combination of variables. The crude ethanol extract (CEE) obtained under optimum extraction conditions was sequentially fractionated with solvents of increasing polarity. The content of total phenolic (TP) and total flavonoid (TF) as well as the antioxidant and antiglycation activities were measured. The phytochemical fingerprint profile of the fraction with the highest activity was characterized by using RP-HPLC. The ethyl acetate fraction (EAF) had the highest TP and TF contents and exhibited the most potent antioxidant and antiglycation activities. The Pearson correlation analysis results showed that TP and TF contents were highly significantly correlated with the antioxidant and antiglycation activities. Totally, six compounds were identified in the EAF of E. fragilis, including four phenolic acids and two flavonoids. Additionally, molecular docking analysis also showed the possible connection between identified bioactive compounds and their mechanisms of action. Our results suggest new evidence on the antioxidant and antiglycation activities of E. fragilis bioactive compounds that may be applied in the treatment and prevention of aging and glycation-associated complications.     

Antifeedant and antifouling briaranes from the South China Sea gorgonian <Emphasis Type="Italic">Junceella juncea</Emphasis>

A new briarane diterpene, juncin ZII (1), along with three known briaranes (2–4), was isolated from the EtOH/CH₂Cl₂ extracts of the South China Sea gorgonian Junceella juncea. The structure of 1 was established by extensive spectroscopic analysis, including 1D and 2D NMR data. For compounds 1–4 and eight other briaranes (5–12) isolated from J. juncea previously, the antifeedant activity against second-instar larvae of Spodoptera litura and cytotoxicity against S. litura cells were investigated, and it was observed that they all exhibit medium antifeedant activity. Compounds 1, 8, 9, and 12 also showed potent antifouling activity against the larval settlement of barnacle Balanus amphitrite at nontoxic concentrations with EC₅₀ values of 0.004, 0.005, 2.82, and 0.447 μg/mL, respectively, while all compounds did not show obvious cytotoxicity against tumor cell lines K562, A549, Hela, and Hep-2. Their structure-activity relationship was discussed. Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 44–47, January–February, 2009.