Marine invertebrates and their associated microorganisms are rich sources of bioactive compounds. Among them, coral and its associated microorganisms are promising providers of marine bioactive compounds. The present review provides an overview of bioactive compounds that are produced by corals and coral-associated microorganisms, covering the literature from 2010 to March 2019. Accordingly, 245 natural products that possess a wide range of potent bioactivities, such as anti-inflammatory, cytotoxic, antimicrobial, antivirus, and antifouling activities, among others, are described in this review.

The renin angiotensin system (RAS) is a hormone system that regulates blood pressure and water balance. Excessive activation of this system is considered to be the main cause of hypertension.1) Angiotensin I-converting enzyme (ACE) is the most important regulatory site of RAS. ACE catalyses the conversion of angiotensin I, an inactive decapeptide, into angiotensin II, an octapeptide with potent vasoconstrictive activity. In fact, a number of synthetic ACE inhibitors have been widely used in patients with cardiac failure and renal disease. Moreover, ACE inhibitors have been identified and isolated from a wide range of plant and animal sources. 2-4)Myrica esculenta BUCH-HAM. ex. D. DON. (Myricaceae) is abundant found in India, South China, Japan, Malaysia, and Vietnam. In Vietnam, the plant is widely distributed in mountainous areas at altitudes ranging from 1000 to 2200 m above sea level. The barks are used in Vietnamese folk medicine to treat catarrhal fever, cough, sore throat, and skin disease.5) Several studies on the chemical constituents of M. esculenta have reported the presence of triterpenoids 6) and tannins. 7) We have been studying the effects of components of Myrica species on cardiovascular diseases. Here we report the isolation of a new monoterpenoid glycoside and eleven known compounds from M. esculenta, and discuss their ACE inhibitory activity. Results and DiscussionDried leaves of M. esculenta were extracted with MeOH and fractionated with chloroform (CHCl 3 ), ethyl acetate (EtOAc) and water. From these extracts and subsequently separation, one new and eleven known compounds were isolated and their structures were elucidated using physicochemical and spectroscopic methods. (Fig. 1 One new monoterpenoid glycoside, myresculoside (1), and eleven known compounds, were isolated from methanol extract of Myrica esculenta leaves by repeated column chromatography. The effects of these compounds on angiotensin I-converting enzyme (ACE) inhibition were investigated. Compounds 3 and 4 showed the most potent ACE inhibition with rates of 29.97% and 25.63% at concentration of 100 mM, respectively. Compounds 5, 6, and 11 showed weak activity with inhibitory rates of 0.07-1.41% at concentration of 100 mM.

No abstract

No abstract

Context:Paramignya trimera (Oliv.) Burkill (Rutaceae) has been used to treat liver diseases and cancer. However, the anti-inflammatory effects of this medicinal plant and its components have not been elucidated.Objective: This study investigated chemical constituents of the P. trimera stems and evaluated anti-inflammatory effects of isolated compounds.Materials and methods: Cytotoxicity of isolated compounds (5–40 μM) toward BV2 cells was tested using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) for 24 h. Inhibitory effects of isolated compounds (5-40 μM) on nitrite and PGE2 concentrations were determined using Griess reaction and PGE2 ELISA kit, respectively (pretreated with the compounds for 3 h and then stimulated for 18 h with LPS). Inhibitory effects of compounds (5-40 μM) on iNOS and COX-2 protein expression were evaluated by Western blot analysis (pretreated with the compounds for 3 h and then stimulated for 24 h with LPS).Results: Seven coumarins were isolated and identified as: ostruthin (1), ninhvanin (2), 8-geranyl-7-hydroxycoumarin (3), 6-(6′,7′-dihydroxy-3′,7′-dimethylocta-2′-enyl)-7-hydroxycoumarin (4), 6-(7-hydroperoxy-3,7-dimethylocta-2,5-dienyl)-7-hydroxycoumarin (5), 6-(2-hydroxyethyl)-2,2-dimethyl-2H-1-benzopyran (6), and luvangetin (7). Compounds 1–4 and 7 inhibited NO and PGE2 production in LPS-stimulated BV2 cells, with IC50 values ranging from 9.8 to 46.8 and from 9.4 to 52.8 μM, respectively. Ostruthin (1) and ninhvanin (2) were shown to suppress LPS-induced iNOS and COX-2 protein expression.Discussion and conclusion: The present study provides a scientific rationale for the use of P. trimera in the prevention and treatment of neuroinflammatory diseases. Ostruthin and ninhvanin might have potential therapeutic effects and should be considered for further development as new anti-neuroinflammatory agents.