RESUMEN
The aim of this work was to study the ability ofyeasts isolated from crops and dairy products to convert starch to ethanol. The isolated yeasts were screened for their ability to hydrolyze starch. Six most active strains were identified as Lipomyces mesembrius spp. 5.4, 5.5 and 6.4, Shwanniomyces vanrijiae var yarowii F33, Torulaspora sp. F7 and Candida sp. S26. The selected yeasts produced low levels of ethanol from starch under aerobic conditions - 0.006-0.129 g/l (0.3-0.87 % of theoretical yield) and microaerobic conditions - 0. 089-0.35 g/l (1.61-6.07 % of theoretical yield). These amylolytic yeast strains will be studied as the potential candidates for the cocultivation with efficient ethanol producers which do not possess the ability to directly hydrolyze starch.
Asunto(s)
Candida/metabolismo , Etanol/metabolismo , Lipomyces/metabolismo , Saccharomycetales/metabolismo , Almidón/metabolismo , Torulaspora/metabolismo , Aerobiosis/fisiología , Candida/aislamiento & purificación , Productos Agrícolas/microbiología , Productos Lácteos/microbiología , Fermentación , Hidrólisis , Cinética , Lipomyces/aislamiento & purificación , Saccharomycetales/aislamiento & purificación , Torulaspora/aislamiento & purificaciónRESUMEN
The red yeasts are currently widely discussed and controversial group of yeasts because of the growing number of reports of their ability to become opportunistic pathogens of plants, animals and humans. The aim of this work was complex identifcation of the red yeast culture isolated from gastrointestinal tract of healthy Hucul long-liver from the Carpathians highland region of Ukraine. Torularhodin was found to be a major component within yeast culture carotenoids complex. According to conventional biochemical and morphological approaches as well as to molecular biological investigation of internal transcribed spacer region (ITS) of ribosomal operon it was concluded that isolate belonged to species Rhodotorula mucilaginosa.
Asunto(s)
Tracto Gastrointestinal/microbiología , Rhodotorula/clasificación , Rhodotorula/aislamiento & purificación , Carotenoides/aislamiento & purificación , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Humanos , UcraniaRESUMEN
The ability of three Pseudomonas aeruginosa strains to reduce vanadate under microaerophilic conditions has been studied. It has been demonstrated that P. aeruginosa strains A17, A03 and C25a were able to reduce up to 38-60% pentavalent vanadium present in the medium. Vanadate reduction by P. aeruginosa strains A17, A03 and C25a was not associated with anaerobic respiration. It has been shown that vanadate reduction by P. aeruginosa strains is not the result of the spontaneous process. This is the first report of stimulation of vanadate reduction by ATPase activity inhibitor N-N-dicyclohexylcarbodiimide under aerobic conditions.
Asunto(s)
Pseudomonas aeruginosa/metabolismo , Vanadatos/química , Adenosina Trifosfatasas/antagonistas & inhibidores , Adenosina Trifosfatasas/metabolismo , Aerobiosis , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/metabolismo , Medios de Cultivo , Diciclohexilcarbodiimida/farmacología , Inhibidores Enzimáticos/farmacología , Oxidación-Reducción , Pseudomonas aeruginosa/efectos de los fármacosRESUMEN
Two Kluyveromyces marxianus strains have been tested for their ability to ferment lactose in the medium containing cheese whey powder (CWP) and lactose at different concentrations. The ethanol production by the selected strains was inhibited by the increase in substrate concentration (100 g/l). The strain K. marxianus UCM Y-2096 was found to yield the higher ethanol formation and to be more resistant to ethanol under microaerophilic conditions.
Asunto(s)
Etanol/metabolismo , Fermentación , Kluyveromyces/metabolismo , Proteínas de la Leche/metabolismo , Recuento de Colonia Microbiana , Cinética , Lactosa/metabolismo , Proteína de Suero de LecheRESUMEN
The yeast strains (n=160) have been isolated from various flowering plants and bees Apis mellifera. Oil-spreading method was used to assay the ability of the isolated yeasts to produce biosurfactants. Five most active strains able to synthesize glycolipid biosurfactants produced the oil-spreading zone with diameter 3.66-50 cm The addition of oleic acid, sunflower oil and octadecane significantly increased biosurfactant activity of the studied strains. Crude biosurfactants produced by the strains Candida sp. 79a and 156a were isolated as ethyl acetate extract and proved to be a mixture of glycolipids by thin-layer chromatography.
Asunto(s)
Candida/aislamiento & purificación , Candida/metabolismo , Glucolípidos/biosíntesis , Tensoactivos/metabolismo , Alcanos/metabolismo , Animales , Abejas/microbiología , Candida/crecimiento & desarrollo , Cromatografía en Capa Delgada , Flores/microbiología , Glucolípidos/química , Glucolípidos/aislamiento & purificación , Ácido Oléico/metabolismo , Aceites de Plantas/metabolismo , Plantas/microbiología , Aceite de Girasol , Tensoactivos/química , Tensoactivos/aislamiento & purificaciónRESUMEN
The search for lactose-fermenting yeast strains has been conducted among 162 strains isolated from various plants and 28 yeast strains isolated from cheese. Four yeast strains have been shown to ferment lactose. They have been identified as Candida kefyr. Specific beta-galactosidase activity of the studied strains grown on lactose-containing medium was 1501-2113 U/g cell. The ethanol production by strains C. kefyr C24 and C30 was significantly inhibited by the increase in substrate concentration (100 g/l).