ABSTRACT
One hundred and eighty one yeast strains were isolated from 180 soil samples collected in three types of forest. The samples were taken during one year. The yeast species found were similar in spite of distinct forest types. Cryptococcus laurentii, Cystofilobasidium capitatum, Leucosporidium scottii, Rhodotorula aurantiaca, and Trichosporon cutaneum were the predominant species in both deciduous and coniferous forests. The number of yeasts ranged from 1.5 x 10(3) to 1.1 x 10(4) CFU/g soil. We found that yeasts occurred unevenly in soils during the year. The lowest number of yeasts was ascertained in December and the highest one in May.
Subject(s)
Soil Microbiology , Trees , Yeasts/isolation & purification , Ecosystem , Yeasts/classificationABSTRACT
One hundred and seventy yeast strains belonging to 14 genera and 29 species were isolated from 112 water samples of the river Danube in the area of Bratislava. The samples were collected through the year from April to March. Saccharomyces cerevisiae, Candida maltosa, Aureobasidium pullulans, Cystofilobasidium capitatum, Rhodotorula glutinis, Geotrichum candidum, and Candida krusei were the most frequent. The basidiomycetous yeasts and yeast-like organisms with oxidative metabolism were present in approximately equal numbers to those with fermentative metabolism. Saccharomyces cerevisiae was the dominant yeast and was isolated from 50% of all samples examined and represented approximately one quarter of the yeast community. Yeast densities ranged from 100 to 21,100 CFU per litre. The highest population density was observed in October. Cryptococcus albidus, Saccharomyces cerevisiae, Rhodotorula glutinis, and Aureobasidium pullulans formed the main part of the yeast population in this month.
Subject(s)
Ascomycota/isolation & purification , Basidiomycota/isolation & purification , Water Microbiology , Aerobiosis , Bacteriological Techniques , Colony Count, Microbial , Culture Media/metabolism , Ecology , Environmental Microbiology , Fermentation , Saccharomyces cerevisiae/isolation & purification , Seasons , SlovakiaABSTRACT
The killer activity of 46 strains belonging to 12 yeast and yeast-like species isolated from water or sediment samples was studied. Only two strains of the genus Cryptococcus did not show killer activity. Killer activity of yeast-like species Aureobasidium pullulans, Hyphopichia burtonii and Geotrichum candidum, and yeast species Candida krusei and Candida lambica was low. Sporobolomyces salmonicolor, Cryptococcus laurentii and Cryptococcus albidus had better activity against basidiomycetous than ascomycetous species. Hansenula anomala strains showed good activity against Geotrichum candidum strains, Cryptococcus albidus, and Sporobolomyces salmonicolor. Rhodotorula species showed activity against the majority of both ascomycetous and basidiomycetous species.
Subject(s)
Fungal Proteins/physiology , Mycotoxins , Water Microbiology , Yeasts/physiology , Ascomycota/physiology , Basidiomycota/physiology , Geologic Sediments/microbiology , Hydrogen-Ion Concentration , Killer Factors, Yeast , Slovakia , Temperature , Water Pollutants/metabolism , Yeasts/isolation & purificationABSTRACT
Fifteen genera and 29 yeast species were found in the water of three fish-ponds located in the area of the Lowland Zahorie (Slovakia). The fish-ponds were sampled in summer and autumn. Aureobasidium, Sporobolomyces, Candida, and Cryptococcus species occurred the most frequently. The composition of yeast species was more heterogeneous in summer than in autumn, but the number of yeasts observed in autumn was 5.5 times higher than those isolated in summer. Some species of the genus Candida, Hyphopichia burtonii, Aureobasidium pullulans, Hansenula anomala and Cryptococcus laurentii were frequently isolated in summer in high counts. The occurrence of the "black yeasts" A. pullulans increased in autumn and together with red yeasts Sporobolomyces roseus represented approximately 70% of the yeast population.
