Secondary Metabolites with Anti-Inflammatory Activities from One Actinobacteria Amycolatopsis taiwanensis

Phytochemical investigation and chromatographic separation of extracts from one new actinobacteria strain Amycolatopsis taiwanensis that was isolated from soil of Yilan township, in the north of Taiwan, led to the isolation of nine new compounds, amycolataiwanensins A–I (1–9, resp.), and one new natural product, namely amycolataiwanensin J (10). The structures of the new compounds were unambiguously elucidated on the basis of extensive spectroscopic-data analysis (1D- and 2D-NMR, MS, and UV) and comparison with literature data. The effect of some isolates on the inhibition of NO production in lipopolysaccharide-activated RAW 264.7 murine macrophages was evaluated. Of the isolates, 3, 5, 7 and 8 exhibited potent anti-NO production activity, with IC₅₀ values of 17.52, 12.31, 17.81 and 13.32 μM, respectively, compared to that of quercetin, an iNOS inhibitor with an IC₅₀ value of 35.94 μM. This is the first report on indole metabolite from the genus Amycolatopsis.     

Synthesis and property comparison of isomeric AB‐type homo‐ and copoly(etherimide)s

AB‐type homo‐ and copoly(etherimide)s were prepared by the polymerization of 3‐ and 4‐(3,4‐dicarboxyphenyloxy)aniline hydrochlorides ( 3A and 4A ) at 160 °C in dimethylacetamide in the presence of triethylamine and triphenyl phosphite. After the structures of the polymers were characterized, their solubilities, ultraviolet–visible (UV–vis) absorption behaviors, thermal properties, and crystallinities were measured, and these properties are discussed with respect to the structure of the homopolymers and the composition of the copolymers. Poly(etherimide) (PEI) derived from 3A [PEI( 3A )] was amorphous and soluble in chloroform on heating, whereas that derived from 4A [PEI( 4A )] was crystalline and insoluble in common organic solvents even on heating. In UV–vis absorption spectra, PEI( 4A ) showed a small bathochromic shift relative to N‐phenylphthalimide, but PEI(3A) did not. PEI(3A) revealed a glass‐transition temperature (T_g) at 195 °C, but no T_g was detectable for PEI( 4A ). All the measured physical properties of the copoly(etherimide)s showed a good dependence on their composition between PEI( 3A ) and PEI( 4A ). © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 402–410, 2000     

A line‐scan hyperspectral Raman system for spatially offset Raman spectroscopy

Spatially offset Raman spectroscopy (SORS) is a technique that can obtain subsurface layered information by collecting Raman spectra from a series of surface positions laterally offset from the excitation laser. Currently optical fiber probes are used as major tools in SORS measurement, which are either slow (single fiber probe with mechanical movement) or restricted in selecting offset range and interval (fiber probe array). This study proposes a new method to conduct SORS measurement based on a newly developed line‐scan hyperspectral Raman imaging system. A 785‐nm point laser was used as an excitation source. A detection module consisting of an imaging spectrograph and a charge‐coupled device camera was used to acquire line‐shape SORS data in a spectral region of −592 to 3015 cm⁻¹. Using a single scan, the system allowed simultaneous collection of a series of Raman spectra in a broad offset range (e.g. 0–36 mm in two sides of the incident laser) with a narrow interval (e.g. 0.07 mm). Four layered samples were created by placing butter slices with thicknesses of 1, 4, 7, and 10 mm on top of melamine powder, providing different individual Raman characteristics to test the line‐scan SORS technique. Self‐modeling mixture analysis (SMA) was used to analyze the SORS data. Raman spectra from butter and melamine were successfully retrieved for all four butter‐on‐melamine samples using the SMA method. The line‐scan SORS measurement technique provides a flexible and efficient method for subsurface evaluation, which has potential to be used for food safety and quality inspection. Copyright © 2015 John Wiley & Sons, Ltd.