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Microwave radiation was used as the heating source in southern pine wood liquefaction with PEG/ glycerin binary solvent. It was found that microwave heating was more efficient than conventional oil bath heating for wood liquefaction. The wood residue content of the H 2 SO 4 catalyzed liquefied wood dropped to zero within 5 min with microwave heating. The resulting liquefied wood polyols have suitable hydroxyl values for the preparation of rigid PU foams. Both the compressive strength and apparent modulus of the liquefied-wood-based PU foams increased as the isocyanate index increased from 80 to 120. The foams from H 3 PO 4 catalyzed polyols had lower densities than those from H 2 SO 4 and the petroleum-based controls. They also showed lower strength and modulus than those from H 2 SO 4 . Liquefied-wood-based PU foams generally have lower compressive strength and apparent modulus than the petroleumbased controls. However, they showed better restorability from deformation than the petroleum-based controls. Zusammenfassung Mittels Mikrowellenstrahlung als Wär-mequelle wurde Southern Pine Holz mit PEG/Glycerin als binärem Lösungsmittelsystem verflüssigt. Es zeigt sich, dass Holz mittels Mikrowellenerhitzung effizienter verflüssigt werden kann als mittels konventioneller Erhitzung im Ölbad. Der Restholzanteil des mit Katalysator H 2 SO 4 verflüssigten Holzes fiel nach fünfminütiger Mikrowellenbeheizung auf Null. Die Hydroxylzahlen der so verflüssigten Holzpolyole sind für die Herstellung von PUHartschaumstoff geeignet. Sowohl die Druckfestigkeit als auch die Steifigkeit der PU-Schaumstoffe aus verflüssigtem Holz nahmen mit steigendem Isocyanatindex von 80 auf 120 zu. Die Schaumstoffe der mit Katalysator H 3 PO 4 erzeugten Polyole wiesen geringere Dichten auf als diejenigen mit Katalysator H 2 SO 4 und als Schaumstoffe auf Mineralölbasis. Die Festigkeit und der E-Modul waren ebenfall geringer. PU-Schaumstoffe auf Basis von verflüssigtem Holz wiesen generell eine niedrigere Druckfestigkeit und eine niedrigere Steifigkeit auf als die Kontrollproben auf Mineralölbasis. Allerdings zeigten sie ein besseres Rückverformungsverhal-ten als die Kontrollproben auf Mineralölbasis.

The objective of this investigation was to find a simple method for the production of phenolic rich products and sugar derivatives (biopolyols) via separation of liquefied lingocellulosic materials. Liquefaction of lignocellulosic materials was conducted in methanol at 180°C for 15 min with the conversion of raw materials at about 75%. After liquefaction, the liquefied products were separated by addition of a sufficient amount of water. It was found that the hydrophobic phenolics could be largely separated from aqueous solutions. The phenolic products that precipitated from the aqueous phase were mainly composed of phenolic derivatives such as 2-methoxy-4-propyl-phenol and 4-hydroxy-3-methoxybenzoic acid methyl ester. Afterwards, the aqueous solution was distilled under vacuum to remove water and formed a viscous liquid product henceforth termed biopolyol. As evidenced by GC-MS analysis, the biopolyols contained methyl sugar derivatives, including methyl β-D-mannofuranoside, methyl α-D-galactopyranoside, methyl α-D-glucopyranoside, and methyl β-D-glucopyranoside. The effect of glycerol on promotion of the liquefaction reaction was also studied. The yield of residue was significantly decreased from approximately 25 to 12% when a glycerol-methanol mixture was used as solvent rather than methanol. According to the GC-MS analysis, the total content of phenolics and poly-hydroxy compounds (including glycerol and sugar derivatives) in phenolic products and biopolyols was 65.9 and 84.9%, respectively. Therefore, a new method for fractionation of liquefied products was proposed according to the molecular structure of the biomass.

Tripyrrole molecules have received renewed attention due to reports of numerous biological activities, including antifungal, antibacterial, antiprotozoal, antimalarial, immunosuppressive, and anticancer activities. In a screen of bacterial strains with known toxicities to termites, a red pigment-producing strain, HDZK-BYSB107, was isolated from Chamaecyparis lawsoniana, which grows in Oregon, USA. Strain HDZK-BYSB107 was identified as Serratia marcescens subsp. lawsoniana. The red pigment was identified as prodigiosin using ultraviolet absorption, LC-MS, and 1H-NMR spectroscopy. The bacterial prodigiosin had an inhibitory effect on both Gram-negative and Gram-positive bacteria. The main objective of this study was to explore the anticancer activities and mechanism of strain HDZK-BYSB107 prodigiosin by using human choriocarcinoma (JEG3) and prostate cancer cell lines (PC3) in vitro and JEG3 and PC3 tumor-bearing nude mice in vivo. In vitro anticancer activities showed that the bacterial prodigiosin induced apoptosis in JEG3 cells. In vivo anticancer activities indicated that the prodigiosin significantly inhibited the growth of JEG3 and PC3 cells, and the inhibitory activity was dose and time dependent. The anticancer efficacy of the bacterial prodigiosin on JEG3 and PC3 cells, JEG3 and PC3 tumor exhibited a correlation with the down regulation of the inhibitor of IAP family, including XIAP, cIAP-1 and cIAP-2, and the activation of caspase-9 and caspase-3 accompanied by proteolytic degradation of poly (ADP-ribose)-polymerase. The expressions of P53 and Bax/Bcl-2 in JEG3 and PC3 cells were significantly higher than in untreated groups. Our results indicated that the bacterial prodigiosin extracted from C. lawsoniana is a promising molecule due to its potential for therapeutic applications.

ABSTRACT:The amount of wood residue is used as a measurement of the extent of wood liquefaction. Characterization of the residue from wood liquefaction provides a new approach to understand some fundamental aspects of the liquefaction reaction. Residues were characterized by wet chemical analyses, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The Klason lignin content of the residues decreased, while the holocellulose and a-cellulose contents increased as the phenol to wood ratio (P/W) increased. A peak at 1735 cm-', which was attributed to the ester carbony1 group in xylan, disappeared in the FTIR spectra of the residues from liquefied wood under a sealed reaction system, indicating significantly different effects of atmospheric versus sealed liquefaction. The crystallinity index of the residues was higher than that of the untreated wood particles and slightly increased with an increase in the P/W ratio. The SEM images of the residues showed that the fiber bundles were reduced to small-sized bundles or even single fibers as the P/W ratio increased from 1/1 to 3/1, which indicated that the lignin in the middle lamella had been dissolved prior to the cellulose during liquefaction. 63 2007 Wiley Periodicals, Inc.