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Aims: To assess the in¯uence of sporulation media on heat resistance, and the use of stress recovery media to measure preservation injury of spores of ®ve representative spoilage bacilli. Methods and Results: Bacillus spores prepared on nutrient agar supplemented with Ca 2+ , Mg 2+ , Mn 2+ , Fe 2+ and K + were more heat-resistant than spores obtained from nutrient agar with Mn 2+ . This increased heat resistance correlated with a decrease in the protoplast water content as determined by buoyant density sedimentation. The degree of preservation injury severity could be assessed on media containing NaCl at moderate pH and organic acids at acid pH. Ca-DPA, K + or proline were added to the recovery media to demonstrate that heat probably caused injury to both spore germination and the outgrowth system. Signi®cance and Impact of the Study 2 : The metal content of sporulation media can strongly effect the validity of preservation resistance studies. The distinctive recovery media developed here can be relevant for assessing and comparing new preservation technologies.

The white rot fungus Bjerkandera sp. strain BOS55 produces veratryl, anisyl, 3-chloroanisyl, and 3,5-dichloroanisyl alcohol and the corresponding aldehydes de novo from glucose. All metabolites are produced simultaneously with the extracellular ligninolytic enzymes and have an important physiological function in the fungal ligninolytic system. Both mono-and dichlorinated anisyl alcohols are distinctly better substrates for the extracellular aryl alcohol oxidases than veratryl alcohol. The aldehydes formed are readily recycled by reduction by washed fungal mycelium, thus creating an extracellular H202 production system regulated by intracellular enzymes. Lignin peroxidase does not oxidize the chlorinated anisyl alcohols either in the absence or in the presence of veratryl alcohol. It was therefore concluded that the chlorinated anisyl alcohols are well protected against the fungus's own aggressive ligninolytic enzymes. The relative amounts of veratryl alcohol and the chlorinated anisyl alcohols differ significantly according to the growth conditions, indicating that production of veratryl alcohol and the production of the (chlorinated) anisyl metabolites are independently regulated. We conclude that the chlorinated anisyl metabolites biosynthesized by the white rot fungus Bjerkandera sp. strain BOS55 can be purposefully produced for ecologically significant processes such as lignin

Intestinal microorganisms play an important role in plant fiber degradation by larvae of the rose chafer Pachnoda marginata. In the hindgut of the larvae 2.5 to 7.4 x 10(8) bacteria per ml of gut content with xylanase or endoglucanase activity were found. Bacteria in the midgut were not (hemi)cellulolytic, but the alkaline environment in this part of the intestinal tract functions as a precellulolytic phase, solubilizing part of the lignocellulosic material. Accordingly, the degradation of lignocellulose-rich material in Pachnoda marginata larvae appeared to be a combination of a physico-chemical and microbiological process. A number of different facultative anaerobic and strictly anaerobic bacteria with (hemi)cellulolytic activity were isolated from the hindgut. A dominant (hemi)cellulolytic species was a Gram positive, irregular shaped, facultative aerobic bacterium. Further physiological identification placed the isolate in the genus Promicromonospora. Comparative 16S rDNA analysis and phenotypic features revealed that the isolate represented a new species for which the name Promicromonospora pachnodae is proposed. P. pachnodae produced xylanases and endoglucanases on several plant derived polymers, both under aerobic and anaerobic conditions.