Fungi are commonly involved in dairy product spoilage and the use of bioprotective cultures can be a complementary approach to reduce food waste and economic losses. In this study, the antifungal activity of 89 Lactobacillus and 23 Pediococcus spp. isolates against three spoilage species, e.g., Yarrowia lipolytica, Rhodotorula mucilaginosa and Penicillium brevicompactum, was first evaluated in milk agar. None of the tested pediococci showed antifungal activity while 3, 23 and 43 lactobacilli isolates showed strong antifungal activity or total inhibition against Y. lipolytica, R. mucilaginosa and P. brevicompactum, respectively. Then, the three most promising strains, Lactobacillus paracasei SYR90, Lactobacillus plantarum OVI9 and Lactobacillus rhamnosus BIOIII28 at initial concentrations of 105 and 107 CFU/ml were tested as bioprotective cultures against the same fungal targets in a yogurt model during a 5-week storage period at 10 °C. While limited effects were observed at 105 CFU/ml inoculum level, L. paracasei SYR90 and L. rhamnosus BIOIII28 at 107 CFU/ml respectively retarded the growth of R. mucilaginosa and P. brevicompactum as compared to a control without selected cultures. In contrast, growth of Y. lipolytica was only slightly affected. In conclusion, these selected strains may be good candidates for bioprotection of fermented dairy products.
- Klíčová slova
- Antifungal, Bioprotection, Dairy product, Fungi, Lactobacilli, Pediococci,
- MeSH
- antifungální látky farmakologie MeSH
- Lactobacillus fyziologie MeSH
- mléčné výrobky mikrobiologie MeSH
- Pediococcus fyziologie MeSH
- Penicillium růst a vývoj MeSH
- potravinářská mikrobiologie MeSH
- probiotika MeSH
- Rhodotorula růst a vývoj MeSH
- Yarrowia růst a vývoj MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- antifungální látky MeSH
Fourteen samples of humic acids (HA) were screened for ability to influence reproduction and biodegradation activity of eukaryotic cells in the presence of chosen toxic pollutants. Microorganisms Candida maltosa and Rhodotorula mucilaginosa (soil isolates) were used for all tests. It was observed during our experiments that some samples of humic acids served as a protection against the high concentration of toxic pollutants (phenol, naphtalene etc). This effect can be widely used in many bioremediation technologies.
- MeSH
- biodegradace MeSH
- Candida růst a vývoj izolace a purifikace metabolismus MeSH
- huminové látky * MeSH
- kinetika MeSH
- kultivační média MeSH
- půdní mikrobiologie MeSH
- Rhodotorula růst a vývoj izolace a purifikace metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- huminové látky * MeSH
- kultivační média MeSH
Five yeast strains were isolated from soil and moss samples from the Livingston Island (Antarctica) and identified according to morphological cultural and physiological characteristics. All strains had an optimum growth temperature of 15 degrees C: none grew above 25 degrees C. They assimilated D-glucose, D-galactose, sucrose, cellobiose, trehalose, 2-keto-D-gluconate, D-xylose, D-ribose and melezitose. Four of them were nonfermentative, only one, which formed pseudomycelium fermented glucose, galactose, trehalose. Two strains were identified as pink-red yeasts belonging to genus Rhodotorula--R. minuta and R. mucilaginosa; two were related to the genus Cryptococcus--C. albidus and C. laurentii; one was Candida oleophila.
- MeSH
- Candida růst a vývoj izolace a purifikace metabolismus MeSH
- Cryptococcus růst a vývoj izolace a purifikace metabolismus MeSH
- glukonáty MeSH
- kultivační média MeSH
- kvasinky růst a vývoj izolace a purifikace metabolismus MeSH
- metabolismus sacharidů MeSH
- půdní mikrobiologie * MeSH
- Rhodotorula růst a vývoj izolace a purifikace MeSH
- teplota MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Antarktida MeSH
- Názvy látek
- gluconic acid MeSH Prohlížeč
- glukonáty MeSH
- kultivační média MeSH
Our main objective was to set up reproducible methods for a rapid determination of harmful effects of PCB-containing engine oils on cells. We used a plate method and Scenedesmus quadricauda, Saccharomyces cerevisiae, Rhodotorula glutinis and Pseudomonas putida as test organisms.
- MeSH
- Chlorophyta účinky léků růst a vývoj MeSH
- kvasinky účinky léků růst a vývoj MeSH
- polychlorované bifenyly farmakologie MeSH
- Pseudomonas putida účinky léků růst a vývoj MeSH
- Rhodotorula účinky léků růst a vývoj MeSH
- ropa * MeSH
- Saccharomyces cerevisiae účinky léků růst a vývoj MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- polychlorované bifenyly MeSH
- ropa * MeSH
The growth of yeast strains Saccharomyces cerevisiae, Rhodotorula rubra and Bullera alba isolated from natural lake microflora was examined in the presence of prehydrolysis lignin and/or its water-soluble derivative. The stimulation effect of the water-soluble lignin derivative was higher in comparison with that of unmodified lignin. The structural changes of the lignin macromolecule by the yeasts determined by IR spectroscopy indicate oxidative degradation and demeth(ox)ylation similar to that found with lignin-degrading hyphal fungi. The results indicate a partial utilization of lignin by the yeasts as carbon source.
- MeSH
- biodegradace MeSH
- lignin chemie metabolismus MeSH
- mitosporické houby růst a vývoj metabolismus MeSH
- Rhodotorula růst a vývoj metabolismus MeSH
- Saccharomyces cerevisiae růst a vývoj metabolismus MeSH
- spektrofotometrie infračervená MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
- Názvy látek
- lignin MeSH
The potential oil-producing yeast Rhodotorula gracilis was found to produce higher yields of biomass (13.7 g/L) and lipids (20.3%) in a nitrogen-limited and economically cheaper medium (molasses without yeast extract) in a submerged fermentation system. But, when the yeast was grown on four different wheat bran media by solid-state fermentation technique, different media combinations affected the percent increase in biomass, protein, oil production, fatty acid profile and degree of saturation and unsaturation. The initial lipid content in the control medium was 3.5% while in a medium with wheat bran, molasses, and minerals it was 69.8%. The yeast did not produce alpha-amylase, amyloglucosidase and cellulolytic enzymes for the breakdown of wheat bran. The yeast produced red carotenoids, a precursor of vitamin B12 and some oligounsaturated fatty acids in the fermented product.
- MeSH
- biotechnologie MeSH
- fermentace MeSH
- fortifikované potraviny MeSH
- kultivační média MeSH
- lipidy biosyntéza MeSH
- mastné kyseliny metabolismus MeSH
- metabolismus sacharidů MeSH
- mykologie metody MeSH
- oleje metabolismus MeSH
- potravinářská technologie MeSH
- potravní vláknina metabolismus MeSH
- Rhodotorula růst a vývoj metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- kultivační média MeSH
- lipidy MeSH
- mastné kyseliny MeSH
- oleje MeSH
- potravní vláknina MeSH
The previously described effect of cell suspension density on metabolic and transport phenomena in yeast, apparently caused by inhibition by dissolved carbon dioxide, is also observed with the accumulation ratio of both sugars and amino acids where not only a kinetic but also a energetic factor comes into play. Unlike all previously measured metabolic and transport parameters, the dependence of the accumulation ratio on suspension density is not monotonic but shows a pronounced maximum in the range of 4-8 mg dry wt/ml, depending on yeast species and on cultivation conditions. In Rhodotorula gracilis and in Lodderomyces elongisporus it is not due to CO2 but is semiquantitatively related to the proton-motive force across the plasma membrane as well as to the intracellular ATP content. It is observed both in oxygen and in argon, over a wide range of pH values and of temperatures, but it is suppressed by metabolic inhibitors. It is expressed only in a range of transported solute concentrations between about 0.1 and 10 mM.
- MeSH
- aminokyseliny metabolismus MeSH
- biologický transport MeSH
- buněčná membrána metabolismus MeSH
- deoxyglukosa metabolismus MeSH
- kinetika MeSH
- koncentrace vodíkových iontů MeSH
- kvasinky růst a vývoj metabolismus ultrastruktura MeSH
- metabolismus sacharidů * MeSH
- prolin metabolismus MeSH
- Rhodotorula růst a vývoj metabolismus ultrastruktura MeSH
- Saccharomyces cerevisiae růst a vývoj metabolismus ultrastruktura MeSH
- Saccharomycetales růst a vývoj metabolismus ultrastruktura MeSH
- teplota MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- 6-deoxyglucose MeSH Prohlížeč
- aminokyseliny MeSH
- deoxyglukosa MeSH
- prolin MeSH
The phenotype and genotype of six strains of the genus Rhodotorula Harrison and of one strain of the genus Cryptococcus Phaff et Fell, with anomalous thickening of cell walls were investigated. The present studies showed that the strains investigated represent different stages of the life cycles of the genus Rhodosporidium Banno. The anomalous thickening of the cell walls can be explained by extreme conditions resulting in the formation of surviving forms (teliospores, chlamydospores).
- MeSH
- bakteriální proteiny analýza MeSH
- buněčná stěna analýza MeSH
- Cryptococcus analýza klasifikace růst a vývoj MeSH
- fenotyp MeSH
- glukosamin analýza MeSH
- karotenoidy analýza MeSH
- mitosporické houby klasifikace MeSH
- Rhodotorula analýza klasifikace růst a vývoj MeSH
- spory hub růst a vývoj MeSH
- teplota MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- bakteriální proteiny MeSH
- glukosamin MeSH
- karotenoidy MeSH
