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Potent and specific inhibitors of hyaluronidases, a group of enzymes preferentially catalysing the hydrolysis of hyaluronic acid, are not known so far. Such compounds could be useful as pharmacological tools for studying the physiological and pathophysiological role of both hyaluronan and hyaluronidases. The effects of sulphated and non-sulphated structurally different oligosaccharides on bovine testicular hyaluronidase, hyaluronidase from bee venom and hyaluronate lyase from Streptococcus agalactiae (hylB (4755)) were studied with the Morgan-Elson reaction. Several active compounds were identified within a series of sulphated beta-(1,4)-galacto-oligosaccharides. The determined IC (50) values of these sulphated oligosaccharides ranged from 4 microM to 630 microM for all hyaluronan-degrading enzymes. Sulphated oligosaccharides like verbascose, planteose and neomycin showed comparable inhibition on all hyaluronidases, thereby possessing 100 - 500 times the activity of the widely accepted hyaluronidase inhibitor apigenin.

Hydrophilic knotwood extracts from 18 wood species were assessed in disc diffusion and liquid culture tests for antibacterial effects against three species of paper mill bacteria. The Pinus sylvestris, P. resinosa, P. contorta, and P. banksiana extracts decreased or inhibited bacterial growth. The susceptibility order was P. sylvestris > P. resinosa > P. contorta > P. banksiana, correlating with the concentrations of pinosylvin and pinosylvin monomethyl ether in these wood species. Also, Pseudotsuga menziesii and Thuja occidentalis extracts had a small inhibitory effect. The Gram-positive Bacillus coagulans was more susceptible to the extracts than the Gram-negative Burkholderia multivorans and Alcaligenes xylosoxydans. The main components in the Pinus knotwood extracts were pinosylvin monomethyl ether and pinosylvin, suggesting these to be the active components. Therefore, pure pinosylvin, pinosylvin monomethyl ether, and dihydro-pinosylvin monomethyl ether were also tested. All compounds showed antibacterial effects. However, higher concentrations were needed for these pure compounds than for the knotwood extracts. Pinosylvin had stronger antibacterial effects than pinosylvin monomethyl ether. This work shows that knotwood extracts, especially from Pinus species, have a potential for use as natural biocides in papermaking.

A sulfated emodin glucoside, emodin 8-O-beta-D-glucopyranosyl-6-O-sulfate (1), was isolated from the roots of Rheum emodi in an investigation of the active constituents of this Nepalese medicinal plant, and its structure was determined by spectroscopic and chemical methods. Additionally, two rare auronols, carpusin (2) and maesopsin (3), besides other anthraquinones and phenolics, were isolated and identified. Compounds 2 and 3 showed significant antioxidant activity in the DPPH assay, while chrysophanol, physcion, and emodin and their 8-O-glucosides were found to be inactive.

Spathodea campanulata stem bark decoction (SCD) has shown hypoglycemic activity in mice. It was separated by column chromatography into different fractions, which were evaluated for their hypoglycemic, anticomplement and anti-HIV activities. The most polar fraction exerted by far the most prominent effect in different biological models.

Analysis of the proportion of cell types in native wood is important for understanding the environmental stresses including an increasing atmospheric CO2 concentration on the structure of wood, especially for the management of plantation forests which will reduce our reliance on natural forests. The conventional method for determining the proportion of cell types is a quantitative microscopy, which is one of the image analyzing systems using a light microscope combined with a microcomputer. However, it is a lengthy multistep procedure. We have examined the feasibility of using Fourier transform Raman spectroscopy for rapid determination of proportion of cell types (fiber, ray parenchyma, vessels, and axial parenchyma) in native wood with using wood meals of two Eucalyptus species, including samples of various ages and colors. By the application of second derivative transformation of Raman spectroscopic data and the partial least-squares regression, we have successfully obtained highly significant correlations between microscopically measured and Raman predicted values for all traits except vessels with correlation coefficients of >0.9 and 0.8, respectively, in the calibration and in the prediction. This method is valid for all traits since vessels can be calculated by the rest of three traits, and will help to solve the effect of the environmental issues on trees and the supplement of renewable raw materials., (Copyright 1999 Academic Press.)

A water extraction of crushed leaves of Nerium oleander yielded 2.3% of a crude polysaccharide. The main fraction (67%) represents a pectic polysaccharide mainly composed of galacturonic acid besides rhamnose, arabinose and galactose. The polysaccharide structure was characterized by NMR, mild acid- and pectinase treatment combined with GC-MS analyses. In vivo tests for a possible antitumor activity did not result in a significant action. Investigation of immunomodulating activity brought some indications for mitogenic activity and a weak macrophage-mediated cytotoxicity. Increase of phagocytosis could not be doubtlessly assigned to the polysaccharide due to the high amount of endotoxin in the homogenous fraction OLE 2.