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Peanuts are an important crop grown in Egypt for either local consumption or export to European markets. The present study examined the importance of mycotoxigenic Aspergilli in Egyptian peanuts from five different regions (Alexandria, El-Beheira, El- Daqahliya, El-Sharqiya, Asyut) in two seasons (2007, 2008). This led to consideration of different potential strategies to control aflatoxigenic A. flavus strains and associated aflatoxin contamination of peanuts. The most common species in peanuts were from Aspergillus section Flavi, Aspergillus section Nigri and Aspergillus section Circumdati. Both qualitative (coconut cream agar) and quantitative analyses (HPLC) were used to analyse the potential mycotoxin production by strains isolated from peanuts. Of a total of 88 Aspergillus section Flavi strains examined, 90% were aflatoxigenic. Cont/d.

This study was concerned with a chemical and microbiological characterisation of cheese made using milk from Algarvian goat breed. Seasonal variation of the microbiota and the gross chemical composition of the raw and boiled milk and cheese during the lactation period were studied. The cardoon microbiota and the variation of microbiota during ripening were studied also. The lactic acid bacteria (LAB) were isolated, identified to genus level and their technological properties such as bacteriocin production, acidifying capacity, proteolysis and lipolysis were studied. The results showed that boiling milk does not represent a cause of variation in its gross composition and almost all the gross components of the milk and cheese register no variation during the studied period, except for fat, which increased until the middle of the lactation period and decreased after that. In cardoon, the microorganisms that are able to produce spores are the most important, thus analysis of yeasts and moulds was carried out which allowed the arrangement of the tested samples into three groups. Most of the identified moulds from the cardoon samples are from the genus Aspergillus. During the study period, differences in the microbiota of the raw milk were not observed, with Lactococcus and Lactobacillus being the prevalent groups. All the tested microorganisms increased approximately by two orders of magnitude from milk to cheese. Lactobacillus was the predominant group during the maturation period. Total coliforms tended to diminish in the early stages of ripening. Isolates from Lactobacillus and Pediococcus genera showed fast acidification capacity, which could be an indicator of good potential for their use as starter bacteria. Some Lactobacillus produced bacteriocin which can contribute to the removal of other bacteria. Aerococcus, Leuconostoc and Lactobacillus presented high proteolytic activity, which mean they could be used as adjunct cultures to improve proteolysis. Only one isolate (Pediococcus) showed lipolytic activity. In conclusion, by their technological characteristics some isolates could be selected as starter cultures, however, further research of their pathogenesis is necessary before using them in pilot plant production.

For fungal contamination of foodstuffs, there are no fast, reliable, automated techniques to examine growth, nor have any predictive models been developed to describe the growth in the same way as for bacteria. Traditional plating methods can take 3 to 7 days to get adequate results depending on the fungal species utilised and well over a month for challenge testing, an unacceptable delay especially for the food industry. In this study two rapid analysis techniques were investigated, conductimetry (direct and indirect) and turbidimetry (Bioscreen), with the sole objective being to analyse their capability to detect fungal growth in optimum conditions and in the presence of inhibitory agents, in this case sorbic acid and vanillin. Three fungal (Aspergillus niger, Fusarium oxysporum and Pencillium verrucosum) and one yeast species (Saccharomyces cerevisiae) were used, though only A. niger growth was analysed using both of the rapid analysis techniques. Two bacterial species (Escherichia coli and Salmonella enterica serovar typhimurium) were also tested using the conductimetry technique for comparison. It was found that both the impedance and turbidimetry methods provided a sensitive and rapid means of detecting, and, under standardised conditions, measuring the activity of micro-organisms. The rate of response showed close correlation with the concentration of both bacteria and spores in the initial inoculum for each strain tested so correlation curves could be constructed to estimate the number of viable cells and spores in a suspension. Moreover, both methods can be used for the accurate screening of potential antimicrobial substances. In comparison with the turbidimetry method though, the impedance method did show a greater deal of variability and there is the possibility it is unsuitable for the analysis of certain fungal species. In addition the direct impedance technique was found to be completely unusable for the analysis of fungal growth. Despite these disadvantages both are promising rapid alternatives to the standard plating technique.

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Although fungi are essential to functioning of forest ecosystems, ecology of wood decay fungi, particularly rare species, is understudied. <italic> Hericium coralloides,</italic> on the UK red data list, <italic>H. erinaceus </italic> and <italic>Piptoporus quercinus,</italic> UK BAP species, and <italic> H. cirrhatum</italic> are rare in the UK, existing in isolated populations in areas with a history of continuous tree cover. Hericium spp. fruit primarily on beech (<italic>Fagus sylvatica</italic>), and <italic>P. quercinus</italic> exclusively on oak (Quercus spp.). Their ecology is unknown, beyond information on fruit body occurence, combative ability against wood decay fungi and extension rates on agar. Their ecology in terms of spore dispersal and germination, and inter- and intraspecific interactions was investigated. Basidiospore dispersal of Hericium spp. was typical of basidiomycetes over the distances investigated (0-100 m from fruit bodies), but basidiospore germination was consistently under 1% in the laboratory. Mating systems of <italic>H. coralloides</italic> and <italic>H. erinaceus</italic> were bifactorial, confirming previous research using North American isolates. <italic>H. cirrhatum'</italic>s mating system remains unclear, due to anomalous clamp connections. Mating experiments also showed that <italic>H. coralloides</italic> from different host species can interbreed, and fruit bodies occurring simultaneously on a substrate may originate from a single mycelium. <italic>H. coralloides</italic> was successfully established artificially in living beech, revealed using molecular techniques. Primary mycelia of <italic>H. coralloides</italic> were more combative than secondary, indicating the significance of this lifecycle stage for rare species. <italic> P. quercinus</italic> had under 1% spore germination and unifactorial mating. The six populations sampled had only four mating alleles, two being unique to one fruit body. This implies inbreeding, but phenotypic variation (extension rates and colony morphology) prove the population is not clonal. Results are discussed in relation to ecology of rare fungi in general, possible factors relating to the rarity of Hericium spp. and <italic>P. quercinus,</italic> and potential conservation strategies for these species.