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Four new bisamides1–4, and two new rhamnosides (5,6), along with four known compounds7–10, were isolated from a scale culture of the mangrove-derived actinomyceteStreptomycessp. SZ-A15. All structures were determined through analysis of the UV, IR, HRESIMS, 1D and 2D NMR spectra as well as by comparison with literature data. BRD4 inhibition of all isolated compounds was evaluated. As for the ability to inhibit protein BRD4, compound9exhibited moderate activity with the value of 78.4 ± 2.2% at 10 μM. [ABSTRACT FROM PUBLISHER]

A fermentation of marine fungus Penicillium janthinellum DT-F29 on solid rice medium led to the isolation of three new compounds, brefeldin D (1) and penialidins D-E (5–6), along with other five known brefeldins and penialidins. The structures of above compounds were determined on the basis of MS and NMR analysis. [ABSTRACT FROM AUTHOR]

This paper investigates the issue of stability and bifurcation for a delayed fractional neural network with three neurons by applying the sum of time delays as the bifurcation parameter. Based on fractional Laplace transform and the method of stability switches, some explicit conditions for describing the stability interval and emergence of Hopf bifurcation are derived. The analysis indicates that time delay can effectively enhance the stability of fractional neural networks. In addition, it is found that the stability interval can be varied by regulating the fractional order if all the parameters are fixed including time delay. Finally, numerical examples are presented to validate the derived theoretical results. [ABSTRACT FROM AUTHOR]

Secondary metabolites profiles of co-culture of Aspergillus flavipes and Streptomyces sp. that isolated from the same habitat showed an induced production of a series of cytochalasans (five aspochalasins and rosellichalasin, determined by MS and NMR analysis). These cytochalasans were found to be produced by A. flavipes in LC–MS comparison analysis, and biological activity assays revealed that they were able to cause cytotoxic effects against Streptomyces sp. within a wide range of concentrations without causing any effect to the producer A. flavipes, which favoured the producer in competition. Further induction mechanism study applying membrane-separated culture and morphology study with scanning electron microscopy (SEM) suggested that the successful induction of active secondary metabolites required microbial physical contact. [ABSTRACT FROM AUTHOR]

A new eremophilane sesquiterpene, capnodiumone (1), along with five known eremophilane sesquiterpenes (2–6) and eight other compounds (7–14), have been isolated from a mangrove-associated fungusCapnodiumsp. SZ-F22. The chemical structures were elucidated on the basis of extensive spectroscopic analysis. The broth extract of the fungus exhibited a good inhibitory effect on the mycelium growth againstFusarium graminearumat 100 μg/mL, however, all the 14 compounds showed no expected antifungal activity. The probable reasons were discussed. [ABSTRACT FROM PUBLISHER]

Tryptamine derivatives such as tryptamine and bacillamides were strong algicidal compounds promising in controlling harmful algae blooms, but their bioactivity and application researches were hindered by extremely low natural production rates. This study found an induced production of algicidal tryptamine derivatives by co-culture of marineStreptomyceswithBacillus mycoides, and optimised the culture method through changing important factors such as medium nutrition content, culture mode and pH value. The final established co-culture method used only 5 g yeast extracts and 5 g glycerol in 1 L 75% sea water, but got a yield of 14.9 mg/LN-acetyltryptamine, 2.8 mg/LN-propanoyltryptamine, 3.0 mg/L bacillamide A, 13.7 mg/L bacillamide B and 9.6 mg/L bacillamide C, which were all undetectable under normal culture conditions. [ABSTRACT FROM PUBLISHER]

Partial component consensus means that some components of all state variables in a multi-agent system tend to be convergence as time tends to be infinite. It is a dynamics behavior that is weaker than identical consensus. In this paper, partial component consensus of nonlinear multi-agent systems via intermittent pinning control is investigated for the first time, and the intermittent signal can be aperiodic. With the help of permutation matrix method, the corresponding error system is reduced to a new error system. Then, partial component consensus in the multi-agent system is converted into the stability of the new error system with respect to partial variables. Based on matrix theory, graph theory and stability theory of partial variables, some sufficient conditions to guarantee exponential partial component consensus are derived. Finally, numerical simulations are shown to demonstrate correctness of the theoretical results. • Partial component consensus dependence on exponential partial variable stability is discussed for the first time. • The internal communication network between agents is a directed graph. • Aperiodically and periodically intermittent pinning control are taken into account, respectively. • Some novel criteria for partial component consensus via intermittent pinning control protocols are derived. [ABSTRACT FROM AUTHOR]