Staining fungi

The Gram-Weigert stain is used to stain the cyst walls of P. carinii cysts. It also stains fungi and many bacteria. Impression... 

A few studies have been performed examining the resistance of acetylated wood to mould and stain fungi in a laboratory environment (Wakeling etal., 1991, 1992). These studies found that acetylation reduced the rate of mould growth, but at the end of the test there was no difference in the extent of colonization. Furthermore, samples modified to a WPG of 10 % exhibited a higher rate of colonization for reasons that were not clear. Samples acetylated up to a WPG of 20 % did not exhibit any improvement in performance in terms of mould growth, compared to unmodified samples, when exposed in a field trial. 

Wakeling, A.N., Plackett, D.V. and Cronshaw, D.R. (1991). The susceptibility of acetylated Pinus radiata to mould and stain fungi. In Proceedings of the International Symposium on Chemical Modification of Wood, Kyoto, Japan, Takahashi, M. (Ed.), pp. 142-147. 

Boon, M. E., Barlow, Y., Marres, E. M., and Milios, J. 1998. Microwave-stimulated lones-Marres method for staining fungi in brain tissue of immunocompromised patients. Methods Enzymol. 75 123-131. 

Planing air-dried lumber largely removes surface discoloration caused by moulds, but discoloration in the wood caused by staining fungi cannot be removed. 

Points 1 and 4 need no further comment. The requirement of 2 is also obvious, considering that this treatment is restricted only to a thin surface layer of the wood and a delay of the treatment allows staining fungi to penetrate beyond the treated layer, where their growth is uninhibited. 

Ayer, W. Kawahara, N. "Lecythophorin, a potent inhibitor of blue-stain fungi, from the hyphomycetous fungus Lecythophora hoffmannii", Tetrahedron Lett., 1995, 36, 7953-7956. 

Optical purity has also been shown to Influence the fungistatic properties of oleoresln monoterpenes. The growth of blue-stain fungi (Ceratocytls spp.) and Fomes annosus Is... 

Wood-Staining Fungi. These fungi are of two types ... 

Although blue stain fungi do not cause decay of wood, they lower the quality of wood and wood products (Fig. 1). In the pulping process, blue stain reduces pulp brightness, which leads to significant increases in the... 

The two most important aspen blue stain fungi are Ophiostoma crassivaginatum and O. piliferum. The secondary metabolites of the blue stain fungus O, crassivaginatum were studied in an attempt to obtain insight into the nature of the staining material. Several simple phenolic compounds were identified which, at least in part, can be responsible for the discoloration of aspen wood infected with this fungus (72). 

An unidentified Zythiostroma species, isolated from aspen, was also found to be antagonistic to O. crassivaginatum. Zythiostromic acids A (25) and B (26), as well as zythiostromolide (27) isolated from the culture broth of this fungus, although new natural compounds, were inactive against the blue stain fungi (16) (Chart 5). 

Lecythophorin (29) shows very good activity at 1 pg/ml against the blue stain fungi (20), but the fact that the fermentation yield is very low and synthetic preparations of this compound will, presumably, not be possible on a commercial scale, precludes the use of this compound in the field. 

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