Yeasts and filamentous fungi associated with some dairy products in Egypt.

This work aimed to identify and evaluate the diversity of yeasts and filamentous fungi that contaminate some dairy products (fresh buffalo milk, plain yoghurt, butter and Kareisk cheese) in Assiut city, Egypt. The identification was based on phenotypic characteristics, and genotypically in case of yeasts. The pHs of all dairy products lie within the acidic range, but yoghurt registered the highest value. A total of 41 genera and 89 species+3 varieties were recovered from all dairy products investigated on DRBC (26 genera representing 59 species+1 variety), DG18 (32 genera, 56 species+2 varieties) and MY50G (31 genera, 64 species+2 varieties). From these, filamentous fungi were represented by 21 genera and 59 species+2 varieties, and yeasts by 20 genera and 30 species+1 variety. In all products except yoghurt, the xerophilic media (DG18 and MY50G) supported more diversity of fungal species than the general medium (DRBC). Reversely, DRBC supported more propagules originated from all products than DG18 and DRBC. On the other hand, the highest numbers of propagules were recovered from Kareish cheese and butter on MY50G, while the lowest numbers were recorded from yoghurt and raw milk on MY50G. Moreover, yeasts constituted the greatest part of propagules from the four products on the three isolation media except the raw milk on MY50G. From yeasts, Candida, Cyberlindnera, Debaryomyces, Galactomyces, Kazachstania, Kluyveromyces, Myerozyma, Pichia, Rhodotorula, Trichosporon; and from filamentous fungi, only Aspergillus, Cladosporium, Mucor and Penicillium were found contaminating all dairy products. Possible medical problems related to the presence of these fungi or to their metabolic products are discussed.

Incidence and biodiversity of yeasts, dermatophytes and non-dermatophytes in superficial skin infections in Assiut, Egypt.

OBJECTIVE: The aim was to identify the incidence of the causal agents from dermatophytes, non-dermatophytes and yeasts in Assiut Governorate employing, beside the morphological and physiological techniques, the genotypic ones. PATIENTS: Samples from infected nails, skin and hair were taken from 125 patients. MATERIALS AND METHODS: Patients who presented with onychomycosis, tinea capitis, tinea corporis, tinea cruris and tinea pedis during the period from February 2012 to October 2015 were clinically examined and diagnosed by dermatologists and were guided to Assiut University Mycological Centre for direct microscopic examination, culturing and identification. RESULTS: Onychomycosis was the most common infecting (64.8% of the cases) followed by tinea capitis (17.6%). Direct microscopic preparations showed only 45 positive cases, while 96 cases showed positive cultures. Infections were more frequent in females than males. Fifty-one fungal species and 1 variety were obtained. Yeasts were the main agents being cultured from 46.02% of total cases. Non-dermatophytes were the second etiologic agents. Aspergillus was responsible for infecting 19.47% of total cases and dermatophytes appeared in only 15.93% of the cases. CONCLUSIONS: Yeasts were the main causal agents followed by non-dermatophytic fungi (mainly species of Aspergillus, then Alternaria, Scopulariopsis and Fusarium). Both direct microscopic preparations and culturing are recommended for mycological evaluation of clinical specimens. Sequence analysis of ITS region is recommended for yeast identification.

Bulbs mycoflora and their relation with three stored product mites.

The distribution of moulds on stored and field onion and garlic plants infested by bulb mites in Assiut area (Egypt) was studied using PDA medium at 28 degrees C. Among 40 host samples and the three mite species tested no significant difference was noted in the contamination by moulds. A total of 20 species appertaining to 11 genera were identified from the tested mites and their habitats. The predominant moulds on all samples were "storage moulds" from the genera Aspergillus (A. niger, A. versicolor) and Penicillium (P. chrysogenum, P. funiculosum, and "field moulds" among which Alternaria, Cladosporium, Fusarium (and its teleomorphs) and Setosphaeria were encountered most frequently. One fungus well known facultative pathogen was obtained: Beauveria bassiana. The tested mites transfer A. niger, N. haematococca, R. stolonifer and P chrysogenum outside their bodies while, A. flavus and A. ochraceus transfer through their digestive tracts along with the foods. Individuals of all mites could survived till the end of the experiment on all fungal species tested except A. niger, A. ochraceus and A. sydowii. Among 48 isolates screened for their ability to produce chitinase, about 83% of the isolates could produce this enzyme. Most of the positive isolates (17 isolates) had moderate producers

Mycoflora inhabiting water closet environments.

Sixty-six fungal species in addition to two species varieties belonging to 31 genera were isolated during the current study from water closet (WC) sewage samples (39 species and two varieties in 20 genera) and WC air (53 species and two varieties in 25 genera). There were more fungi in the WC air than in sewage. The most prevalent fungi in WC sewage and air were members of the genera Aspergillus, Cladosporium and Penicillium. Acremonium, Alternaria, Emericella, Mycosphaerella and Pleospora were dominant only in WC air. Some species of these genera are considered to be true or opportunistic pathogens. The pollution level due to the bacterial flora either in the air or in the sewage of WCs was relatively higher than that of the fungal flora. Testing the capability to produce urease, nearly all fungal isolates (65 out of 67) and bacteria tested (35 out of 36) proved to be good urease producers.

Mycoflora and natural occurrence of mycotoxins in tobacco from cigarettes in Egypt.

Forty-two species and 4 varieties belonging to 21 genera were collected from 40 tobacco samples on glucose- and cellulose-Czapek's agar at 28 degrees C and 45 degrees C. The most common mesophiles (at 28 degrees C) in tobacco on the two types of media were: Aspergillus flavus, A. flavus var. columnaris, A. fumigatus, A. niger, Penicillium chrysogenum and P. funiculosum. Two samples were heavily contaminated with members of Fusarium (F. moniliforme, F. oxysporum, F. solani). Some fungi were encountered only on plates of cellulose agar as Chaetomium globosum, Stachybotrys atra var. microspora and S. chartarum. At 45 degrees C the most prevalent fungus was A. fumigatus. Truely thermophiles were also collected: Humicola grisea var. thermoidae, Rhizomucor pusillus and Thermoascus aurantiacus. Based on biological assays (brine shrimp larvae (Artemia salina L.) and Bacillus megatherium test) and chemical analysis of chloroform extraction of tobacco (TLC and UV spectrophotometric), four samples (out of 40) had toxicity and four compounds of mycotoxins were detected namely; aflatoxins B1 & B2 (2 samples; 15.5 and 20.7 micrograms/kg), zearalenone (1 sample, 5.5 micrograms) and T-2 toxin (1 sample, 2.8 micrograms). For studying the tracing of aflatoxins in smoking cigarettes, three doses (10, 20 and 50 micrograms) of aflatoxins B1 and B2 (w/w, 1:1) were injected each in ten cigarettes. All extracts of cigarettes smoke proved to be non-toxic and mycotoxins not detected. However, aflatoxins were detected in topping filter (2.8, 3.5 and 8.8 micrograms/the three doses, respectively).