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1.
J Environ Manage ; 362: 121351, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38838535

RESUMO

In this study, the growth of yeast and yeast-like fungi in the liquid digestate from vegetable wastes was investigated in order to remove nutrients and organic pollutants, and for their application as co-culture members with green microalgae. The studied yeast strains were characterized for their assimilative and enzymatic profiles as well as temperature requirements. In the first experimental stage, the growth dynamics of each strain were determined, allowing to select the best yeasts for further studies. In the subsequent stage, the ability of selectants to remove organic pollutants was assessed. Different cultivation media containing respectively 1:3, 1:1, 3:1 vol ratio of liquid digestate and the basal minimal medium were used. Among all tested yeast strains, Rhodotorula mucilaginosa DSM 70825 showed the most promising results, demonstrating the highest potential for removing organic substrates and nutrients. Depending on the medium, this strain achieved 50-80% sCOD, 45-60% tVFAs, 21-45% TN, 33-52% PO43- reduction rates. Similar results were obtained for the strain Candida sp. OR687571. The high nutrient and organics removal efficiency by these yeasts could likely be linked to their ability to assimilate xylose (being the main source of carbon in the liquid digestate). In culture media containing liquid digestate, both yeast strains achieved good viability and proliferation potential. In the liquid digestate medium, R. mucilaginosa and Candida sp. showed vitality at the level of 51.5% and 45.0%, respectively. These strains seem to be a good starting material for developing effective digestate treatment strategies involving monocultures and/or consortia with other yeasts or green microalgae.


Assuntos
Técnicas de Cocultura , Microalgas , Leveduras , Microalgas/crescimento & desenvolvimento , Microalgas/metabolismo , Leveduras/metabolismo , Leveduras/crescimento & desenvolvimento , Rhodotorula/metabolismo , Rhodotorula/crescimento & desenvolvimento , Nutrientes/metabolismo , Biodegradação Ambiental , Candida/crescimento & desenvolvimento , Candida/metabolismo
2.
Biomolecules ; 14(6)2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38927033

RESUMO

It is known that selenium (Se) is an essential trace element, important for the growth and other biological functions of fish. One of its most important functions is to contribute to the preservation of certain biological components, such as DNA, proteins, and lipids, providing protection against free radicals resulting from normal metabolism. The objective of this study was to evaluate and optimize selenium accumulation in the native yeast Rhodotorula mucilaginosa 6S. Sodium selenite was evaluated at different concentrations (5-10-15-20-30-40 mg/L). Similarly, the effects of different concentrations of nitrogen sources and pH on cell growth and selenium accumulation in the yeast were analyzed. Subsequently, the best cultivation conditions were scaled up to a 2 L reactor with constant aeration, and the proteome of the yeast cultured with and without sodium selenite was evaluated. The optimal conditions for biomass generation and selenium accumulation were found with ammonium chloride and pH 5.5. Incorporating sodium selenite (30 mg/L) during the exponential phase in the bioreactor after 72 h of cultivation resulted in 10 g/L of biomass, with 0.25 mg total Se/g biomass, composed of 25% proteins, 15% lipids, and 0.850 mg total carotenoids/g biomass. The analysis of the proteomes associated with yeast cultivation with and without selenium revealed a total of 1871 proteins. The results obtained showed that the dynamic changes in the proteome, in response to selenium in the experimental medium, are directly related to catalytic activity and oxidoreductase activity in the yeast. R. mucilaginosa 6S could be an alternative for the generation of selenium-rich biomass with a composition of other nutritional compounds also of interest in aquaculture, such as proteins, lipids, and pigments.


Assuntos
Proteômica , Rhodotorula , Selênio , Rhodotorula/metabolismo , Rhodotorula/crescimento & desenvolvimento , Rhodotorula/efeitos dos fármacos , Selênio/metabolismo , Selênio/farmacologia , Proteômica/métodos , Biomassa , Reatores Biológicos/microbiologia , Selenito de Sódio/metabolismo , Selenito de Sódio/farmacologia , Concentração de Íons de Hidrogênio , Proteoma/metabolismo , Proteínas Fúngicas/metabolismo
3.
J Basic Microbiol ; 64(7): e2400132, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38751099

RESUMO

In the vitamin C microbial fermentation system, oxidative stress limits the growth and 2-keto-l-gulonic acid (2-KLG, the precursor of vitamin C) production of Ketogulonicigenium vulgare. Most Bacillus strains, as helper strains, have been reported to release key biomolecules to reduce oxidative stress and promote the growth and 2-KLG production of K. vulgare. To understand the specific mechanism by which the helper strain and K. vulgare interact to reduce oxidative stress, a novel helper strain, Rhodotorula mucilaginosa A8, was used to construct a consortium in the co-culture fermentation system. Based on the activities of the antioxidant enzymes and quantitative polymerase chain reaction (qPCR) analysis, R. mucilaginosa A8 could reduce oxidative stress and increase 2-KLG production in K. vulgare by upregulating antioxidant enzyme activities and related gene-expression levels. In addition, the carotenoids of R. mucilaginosa promoted 2-KLG production in K. vulgare. Coculture of R. mucilaginosa with K. vulgare increased the yield of carotenoids. This study suggested that helper strains with the ability to reduce oxidative stress in K. vulgare would likely act as potential helper strains for facilitating 2-KLG biosynthesis. This work could provide a theoretical basis for the search for potential helper strains for vitamin C microbial fermentation and for the construction of synthetic microbial communities to produce valuable products.


Assuntos
Antioxidantes , Ácido Ascórbico , Técnicas de Cocultura , Fermentação , Estresse Oxidativo , Rhodotorula , Ácido Ascórbico/metabolismo , Rhodotorula/metabolismo , Rhodotorula/genética , Rhodotorula/crescimento & desenvolvimento , Antioxidantes/metabolismo , Carotenoides/metabolismo , Interações Microbianas , Açúcares Ácidos
4.
Arch Microbiol ; 206(6): 245, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702537

RESUMO

Production of carotenoids by yeast fermentation is an advantaged technology due to its easy scaling and safety. Nevertheless, carotenoid production needs an economic culture medium and other efficient yeast stains. The study aims to isolate and identify a yeast strain capable of producing carotenoids using a cost-effective substrate. A new strain was identified as Rhodotorula toruloides L/24-26-1, which can produce carotenoids at different pretreated and unpretreated sugarcane molasses concentrations (40 and 80 g/L). The highest biomass concentration (18.6 ± 0.6 g/L) was reached in the culture using 80 g/L of hydrolyzed molasses. On the other hand, the carotenoid accumulation reached the maximum value using pretreated molasses at 40 g/L (715.4 ± 15.1 µg/g d.w). In this case, the ß-carotene was 1.5 times higher than that on the control medium. The yeast growth in molasses was not correlated with carotenoid production. The most outstanding production of The DPPH, ABTS, and FRAP tests demonstrated the antioxidant activity of the obtained carotenogenic extracts. This research demonstrated the R. toruloides L/24-26-1 strain biotechnological potential for carotenoid compounds. The yeast produces carotenoids with antioxidant activity in an inexpensive medium, such as sulfuric acid pretreated and unpretreated molasses.


Assuntos
Fermentação , Melaço , Rhodotorula , Saccharum , beta Caroteno , Rhodotorula/metabolismo , Rhodotorula/genética , Rhodotorula/crescimento & desenvolvimento , Rhodotorula/isolamento & purificação , Rhodotorula/classificação , Saccharum/metabolismo , beta Caroteno/metabolismo , beta Caroteno/biossíntese , Carotenoides/metabolismo , Antioxidantes/metabolismo , Biomassa , Meios de Cultura/química , Filogenia
5.
PLoS One ; 16(2): e0246841, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33592044

RESUMO

In recent years, marine red yeasts have been increasingly used as feed diets for larviculture of aquatic animals mainly due to their rich nutrition and immunopotentiation, however little attention is given to their other probiotic profits. In this study, a marine red yeast strain YLY01 was isolated and purified from farming water and it was identified as a member of Rhodosporidiums sphaerocarpum by the phylogeny based on 18S rDNA sequence. The strain YLY01 could effectively remove ammonia nitrogen from an initial 9.8 mg/L to 1.3 mg/L in 48 h when supplemented with slight yeast extract and glucose in water samples and the removal rate of ammonia nitrogen was up to 86%. Shrimps (Litopenaeus vannamei) in experimental group incubated with the yeast YLY01 exhibited a higher survival rate than those in blank control group and positive control group challenged by Vibrio harveyi, and it manifested that the strain has high biosecurity to at least shrimps. The strain YLY01 could inhibit the growth of Vibrio cells when a small quantity of carbon source was added into farming water. In addition, a nutrition composition assay showed the contents of protein, fatty acids, and total carotenoids of the yeast YLY01 were 30.3%, 3.2%, and 1.2 mg/g of dry cell weight, respectively. All these results indicated that the marine red yeast YLY01 has a great potential to be used as a versatile probiotic in aquaculture and to be developed as a microbial agent for high-ammonia tail water treatment.


Assuntos
Amônia/metabolismo , Organismos Aquáticos/crescimento & desenvolvimento , Rhodotorula/crescimento & desenvolvimento , Vibrio/crescimento & desenvolvimento , Purificação da Água , Leveduras/crescimento & desenvolvimento
6.
World J Microbiol Biotechnol ; 37(1): 18, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33394175

RESUMO

One of the very promising methods in the field of bioremediation of hydrocarbons is the application of biosurfactant- producing microorganisms based on the use of wastewater as renewable substrates of culture media, contributing to the reduction of costs. With this aim, the production, characterization and properties of the yeast strain YBR producing a biosurfactant newly isolated from an oilfield in Algeria, using wastewater from olive oil mills (OOMW) as a substrate for a low-cost and effective production, have been investigated. Screening of biosurfactant production was carried out with different tests, including emulsification index test (E24), drop collapse test, oil spreading technique and measurement of surface tension (ST). The isolated yeast strain was found to be a potent biosurfactant producer with E24 = 69% and a significant reduction in ST from 72 to 35 mN m-1. The study of the cultural, biochemical, physiological and genetic characteristics of the isolate allowed us to identify it as Rhodotorula sp. strain YBR. Fermentation was carried out in a 2.5 L Minifors Bioreactor using crude OOMW as culture medium, the E24 value reached 90% and a reduction of 72 to 35 mN m-1 in ST. A biosurfactant yield = 10.08 ± 0.38 g L-1 was recorded. The characterization by semi-purification and thin layer chromatography (TLC) of the crude extract of biosurfactant showed the presence of peptides, carbohydrates and lipids in its structure. The crude biosurfactant exhibited interesting properties such as: low critical micellar concentration (CMC), significant reduction in ST and strong emulsifying activity. In addition, it has shown stability over a wide range of pH (2-12), temperature (4-100 °C) and salinity (1-10%). More interestingly, the produced biosurfactant has proven to be of great potential application in the remobilization of hydrocarbons from polluted soil with a removal rate of greater than 95%.


Assuntos
Hidrocarbonetos/química , Petróleo/microbiologia , Rhodotorula/crescimento & desenvolvimento , Tensoativos/metabolismo , Biodegradação Ambiental , Reatores Biológicos/microbiologia , Campos de Petróleo e Gás , Filogenia , Rhodotorula/classificação , Rhodotorula/isolamento & purificação , Rhodotorula/metabolismo
7.
Appl Biochem Biotechnol ; 193(4): 998-1010, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33219451

RESUMO

The production of microbial lipid using lignocellulosic agroforestry residues has attracted much attention. But, various inhibitors such as phenols and furans, which are produced during lignocellulosic hydrolysate preparation, are harmful to microbial lipid accumulation. Herein, we developed a novel detoxification strategy of rice straw hydrolysate using immobilized laccase on magnetic Fe3O4 nanoparticles for improving lipid production of Rhodotorula glutinis. Compared with free laccase, the immobilized laccase on magnetic nanoparticles showed better stability, which still retained 76% of original activity at 70 °C and 56% at pH 2 for 6 h. This immobilized laccase was reused to remove inhibitors in acid-pretreated rice straw hydrolysate through recycling with external magnetic field. The results showed that most of phenols, parts of furans, and formic acids could be removed by immobilized laccase after the first batch. Notably, the immobilized laccase exhibited good reusability in repeated batch detoxification. 78.2% phenols, 43.8% furfural, 30.4% HMF, and 16.5% formic acid in the hydrolysate were removed after the fourth batch. Furthermore, these detoxified rice straw hydrolysates, as substrates, were applied to the lipid production of Rhodotorula glutinis. The lipid yield in detoxified hydrolysate was significantly higher than that in undetoxified hydrolysate. These findings suggest that the immobilized laccase on magnetic nanoparticles has a potential to detoxify lignocellusic hydrolysate for improving microbial lipid production.


Assuntos
Enzimas Imobilizadas/química , Lacase/química , Lipídeos/biossíntese , Nanopartículas de Magnetita/química , Rhodotorula/crescimento & desenvolvimento
8.
J Basic Microbiol ; 61(1): 4-14, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32896907

RESUMO

Implementing two-way strategies to enhance the lipid production in Rhodotorula mucilaginosa with the help of metabolic engineering was focused on the overexpression of acetyl coenzyme A carboxylase (ACC1 carboxylase) gene and repression of 3-hydroxy 3-methylglutaryl reductase (HMG-CoA reductase). Using an inducer (sodium citrate) and inhibitor (rosuvastatin), the amounts of biomass, lipid, and carotenoid were estimated. In the presence of inhibitor (200 mM), 62% higher lipid concentration was observed, while 44% enhancement was recorded when inducer (3 mM) was used. A combination of both inhibitor and inducer resulted in a 57% increase in lipid concentration by the oleaginous yeast. These results were again confirmed by real-time polymerase chain reaction by targeting the expression of the genes coding for ACC1 carboxylase and 13-fold increase was recorded in the presence of inducer as compared with control. This combined strategy (inducer and inhibitor use) has been reported for the first time as far as the best of our knowledge. The metabolic engineering strategies reported here will be a powerful approach for the enhanced commercial production of lipids.


Assuntos
Acetil-CoA Carboxilase/genética , Ácidos Graxos/metabolismo , Hidroximetilglutaril-CoA Redutases/genética , Rhodotorula/metabolismo , Biomassa , Carotenoides/metabolismo , Expressão Gênica/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Engenharia Metabólica , Rhodotorula/efeitos dos fármacos , Rhodotorula/genética , Rhodotorula/crescimento & desenvolvimento , Rosuvastatina Cálcica/farmacologia , Citrato de Sódio/farmacologia
9.
Protist ; 171(3): 125738, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32544845

RESUMO

This paper represents a comprehensive study of two new thraustochytrids and a marine Rhodotorula red yeast isolated from Australian coastal waters for their abilities to be a potential renewable feedstock for the nutraceutical, food, fishery and bioenergy industries. Mixotrophic growth of these species was assessed in the presence of different carbon sources: glycerol, glucose, fructose, galactose, xylose, and sucrose, starch, cellulose, malt extract, and potato peels. Up to 14g DW/L (4.6gDW/L-day and 2.8gDW/L-day) of biomass were produced by Aurantiochytrium and Thraustochytrium species, respectively. Thraustochytrids biomass contained up to 33% DW of lipids, rich in omega-3 polyunsaturated docosahexaenoic acid (C22:6, 124mg/g DW); up to 10.2mg/gDW of squalene and up to 61µg/gDW of total carotenoids, composed of astaxanthin, canthaxanthin, echinenone, and ß-carotene. Along with the accumulation of these added-value chemicals in biomass, thraustochytrid representatives showed the ability to secrete extracellular polysaccharide matrixes containing lipids and proteins. Rhodotorula sp lipids (26% DW) were enriched in palmitic acid (C16:0, 18mg/gDW) and oleic acid (C18:1, 41mg/gDW). Carotenoids (87µg/gDW) were mainly represented by ß-carotene (up to 54µg/gDW). Efficient growth on organic and inorganic sources of carbon and nitrogen from natural and anthropogenic wastewater pollutants along with intracellular and extracellular production of valuable nutrients makes the production of valuable chemicals from isolated species economical and sustainable.


Assuntos
Biodegradação Ambiental , Quitridiomicetos , Lipídeos/biossíntese , Rhodotorula , Poluentes da Água/metabolismo , Aciltransferases/metabolismo , Biomassa , Carotenoides/metabolismo , Quitridiomicetos/crescimento & desenvolvimento , Quitridiomicetos/isolamento & purificação , Quitridiomicetos/metabolismo , Ácidos Docosa-Hexaenoicos/biossíntese , Ácidos Graxos Insaturados/biossíntese , Nutrientes/metabolismo , Polissacarídeos/biossíntese , Rhodotorula/crescimento & desenvolvimento , Rhodotorula/isolamento & purificação , Rhodotorula/metabolismo , Água do Mar/microbiologia , Águas Residuárias/microbiologia , Áreas Alagadas
10.
Bioprocess Biosyst Eng ; 43(9): 1629-1638, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32347408

RESUMO

Due to increasing oil prices and climate change concerns, biofuels have become increasingly important as potential alternative energy sources. However, the use of arable lands and valuable resources for the production of biofuel feedstock compromises food security and negatively affect the environment. Single cell oils (SCOs), accumulated by oleaginous yeasts, show great promise for efficient production of biofuels. However, the high production costs attributed to feedstocks or raw materials present a major limiting factor. The fermentative conversion of abundant, low-value biomass into microbial oil would alleviate this limitation. Here, we explore the feasibility of utilizing microalgae-based cell residues as feedstock for yeast oil production. We developed an efficient, single-step enzymatic hydrolysis to generate Scenedesmus obtusiusculus hydrolysate (SH) without thermo-chemical pretreatment. With this eco-friendly process, glucose conversion efficiencies reached 90-100%. Cutaneotrichosporon oleaginosus, Cryptococcus curvatus and Rhodosporidium toruloides were cultivated on SH as sole nutrients source. Only C. oleaginosus was able to accumulate intracellular lipids, with a 35% (g lipid/g DCW) content and a yield of 3.6 g/L. Our results demonstrate the potential valorization of algal biomass into desired end-products such as biofuels.


Assuntos
Basidiomycota/crescimento & desenvolvimento , Biomassa , Lipídeos/biossíntese , Microalgas/química , Rhodotorula/crescimento & desenvolvimento , Scenedesmus/química
11.
Biotechnol Lett ; 42(5): 757-772, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31997042

RESUMO

OBJECTIVE: Oleaginous yeasts are a renewable and alternative source of oil for third-generation biodiesel. This work aimed to evaluate the effects of glucose concentration (30-100 g L-1) on growth, lipid synthesis, and fatty acids (FA) profile of three Rhodotorula spp. (R. glacialis R15, R. glutinis R4, and R. glutinis R48) isolated from Antarctica, and estimate the key quality parameters of the biodiesel produced by yeasts to confirm their potential as feedstocks for third-generation biodiesel synthesis. RESULTS: Yeasts accumulated 50-69.5% of lipids (w/w) under nitrogen-limitation and glucose-excess (C/N = 40-133). Glucose concentration increase influenced positively lipid accumulation (69.5% w/w) and FA profile of R. glacialis R15. Lipid accumulation (53% on average) of R. glutinis strains was not significantly affected by glucose concentration; content of saturated (~ 30%) and polyunsaturated FA (~ 29-30%) was slightly influenced. FA profiles of lipids synthesized by R15, R4, and R48 are similar to vegetable oils used in biodiesel industry with C16 and C18 FA (95-99%) as the major components, and contain mainly oleic (C18:1), palmitic (C16:0), and linoleic (C18:2) acids, which are suitable for biodiesel synthesis. Estimated fuel properties for biodiesel produced by R15, R4, and R48 satisfied all the criteria established by ASTM D6751 and EN 14214 with good cetane number, iodine value, and oxidation stability. An improvement in biodiesel quality of R15 was observed with the glucose increase. The best global properties of biodiesel from R4 were obtained with 30 g L-1 of glucose. CONCLUSIONS: Rhodotorula spp. from Antarctica are promising candidates for third-generation biodiesel synthesis.


Assuntos
Biocombustíveis/análise , Ácidos Graxos/análise , Rhodotorula/crescimento & desenvolvimento , Regiões Antárticas , Biomassa , Meios de Cultura/química , Glucose/metabolismo , Rhodotorula/química , Rhodotorula/metabolismo
12.
Biotechnol Lett ; 42(3): 437-443, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31933056

RESUMO

This study aimed to evaluate the production of carotenoid pigments by Rhodotorula spp. in submerged fermentation, using residual glycerin from biodiesel production as a carbon source. Chromatographic analysis by HPLC showed that the residual glycerin used as substrate was 57.88% composed of glycerol. The best growth conditions were found in the fermentation medium composed of residual glycerin at a concentration of 30 g/L and pH 9. From all the Rhodotorula strains tested, R. minuta URM6693 was selected because of their performance and adaptation in all culture media assayed. The maximum volumetric production of carotenoids was found at 48 h (equivalent to 17.20 mg/L, for the R. minuta). The production of ß-carotene since the first 24 h of fermentation reach a final concentration of 1.021 mg/L. The yeast Rhodotorula minuta proved its capability to efficiently convert the substrate (mainly at the concentration of 50 g/L), obtaining products of biotechnological interest.


Assuntos
Glicerol/metabolismo , Rhodotorula/crescimento & desenvolvimento , beta Caroteno/biossíntese
13.
J Hazard Mater ; 389: 121834, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-31843407

RESUMO

Environmental problems caused by the large-scale use of chemical pesticides are becoming more and more serious, and the removal of chemical pesticides from the ecological environment by microbial degradation has attracted wide attention. In this study, using enrichment screening with seven chemical pesticides as the sole carbon source, a mixed microbial culture (PCS-1) was obtained from the continuous cropping of strawberry fields. The microbial community composition, degradation ability, and detoxification effect of PCS-1 was determined for the seven pesticides. Inoculation with PCS-1 showed significant degradation of and tolerance to the seven pesticides. Microbial community composition analysis indicated that Pseudomonas, Enterobacter, Aspergillus, and Rhodotorula were the dominant genera for the degradation of the seven pesticides by PCS-1. The concentration of the seven pesticides was 10 mg L-1 in hydroponic and soil culture experiments. The fresh weight, plant height, and root length of PCS-1-inoculated alfalfa (Medicago sativa) significantly increased compared with those of non-PCS-1-inoculated M. sativa. PCS-1 not only effectively degraded the residual content of the seven pesticides in water and soil but also reduced the pesticide residues in the roots, stems, and leaves of M. sativa. This study shows that PCS-1 may be important in environmental remediation involving the seven pesticides.


Assuntos
Poluentes Ambientais/análise , Medicago sativa/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Praguicidas/análise , Microbiologia do Solo , Poluentes do Solo/análise , Aspergillus/efeitos dos fármacos , Aspergillus/crescimento & desenvolvimento , Biodegradação Ambiental , Enterobacter/efeitos dos fármacos , Enterobacter/crescimento & desenvolvimento , Poluentes Ambientais/toxicidade , Medicago sativa/crescimento & desenvolvimento , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/toxicidade , Praguicidas/toxicidade , Pseudomonas/efeitos dos fármacos , Pseudomonas/crescimento & desenvolvimento , Rhodotorula/efeitos dos fármacos , Rhodotorula/crescimento & desenvolvimento , Poluentes do Solo/toxicidade
14.
Plant Cell ; 32(2): 486-507, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31757927

RESUMO

Nitrogen (N) limits crop yield, and improvement of N nutrition remains a key goal for crop research; one approach to improve N nutrition is identifying plant-interacting, N2-fixing microbes. Rhodotorula mucilaginosa JGTA-S1 is a basidiomycetous yeast endophyte of narrowleaf cattail (Typha angustifolia). JGTA-S1 could not convert nitrate or nitrite to ammonium but harbors diazotrophic (N2-fixing) endobacteria (Pseudomonas stutzeri) that allow JGTA-S1 to fix N2 and grow in a N-free environment; moreover, P. stutzeri dinitrogen reductase was transcribed in JGTA-S1 even under adequate N. Endobacteria-deficient JGTA-S1 had reduced fitness, which was restored by reintroducing P. stutzeri JGTA-S1 colonizes rice (Oryza sativa), significantly improving its growth, N content, and relative N-use efficiency. Endofungal P. stutzeri plays a significant role in increasing the biomass and ammonium content of rice treated with JGTA-S1; also, JGTA-S1 has better N2-fixing ability than free-living P. stutzeri and provides fixed N to the plant. Genes involved in N metabolism, N transporters, and NODULE INCEPTION-like transcription factors were upregulated in rice roots within 24 h of JGTA-S1 treatment. In association with rice, JGTA-S1 has a filamentous phase and P. stutzeri only penetrated filamentous JGTA-S1. Together, these results demonstrate an interkingdom interaction that improves rice N nutrition.


Assuntos
Bactérias/metabolismo , Basidiomycota/metabolismo , Fixação de Nitrogênio/fisiologia , Nitrogênio/metabolismo , Oryza/metabolismo , Oryza/microbiologia , Rhodotorula/metabolismo , Compostos de Amônio , Basidiomycota/crescimento & desenvolvimento , Endófitos/metabolismo , Regulação da Expressão Gênica de Plantas , Oryza/genética , Oryza/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Pseudomonas/metabolismo , Pseudomonas stutzeri/metabolismo , Rhodotorula/crescimento & desenvolvimento , Rhodotorula/isolamento & purificação , Simbiose , Transcriptoma
15.
Fungal Biol ; 123(12): 913-926, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31733734

RESUMO

Trametes ljubarskyi produces multiple laccase isozymes under various physicochemical conditions. During co-cultivation condition Rhodotorula mucilaginosa showed inter-specific interactions with T. ljubarskyi and hypersecretion of laccases; however, the underlying molecular mechanism is less-known. The analysis of proteomics data of co-cultivated cultures revealed the mechanism of metabolic coupling during fungal-yeast interactions. The results suggested high score GO terms related to stimulus-response, protein binding, membrane components, transport channels, oxidoreductases, and antioxidants. The SEM studies confirmed the cellular communication and their inter-specific interactions. This study allows us to deepen and refine our understanding of fungal-yeast symbiotic interaction; further, it also establishes a mutual relation by metabolic coupling for 10-fold higher laccase isozyme secretion (6532 U/ml). The purified laccase isozymes showed acidic pH optima (pH 3-4), higher thermo-stability (60 °C), and broad enzyme kinetics (Km) values. Our study also provides an in-depth understanding of laccase isozymes and their potential to degrade synthetic dyes, which may help the fungi to survive in an adverse environment.


Assuntos
Isoenzimas/metabolismo , Lacase/metabolismo , Interações Microbianas , Rhodotorula/crescimento & desenvolvimento , Rhodotorula/metabolismo , Trametes/crescimento & desenvolvimento , Trametes/metabolismo , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Proteômica , Rhodotorula/citologia , Rhodotorula/enzimologia , Temperatura , Trametes/citologia , Trametes/enzimologia
16.
Molecules ; 24(21)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683743

RESUMO

Onychomycosis is a major health problem due to its chronicity and resistance to therapy. Because some cases associate paronychia, any therapy must target the fungus and the inflammation. Medicinal plants represent an alternative for onychomycosis control. In the present work the antifungal and antioxidant activities of Alium sativum extract against Meyerozyma guilliermondii (Wick.) Kurtzman & M. Suzuki and Rhodotorula mucilaginosa (A. Jörg.) F.C. Harrison, isolated for the first time from a toenail onychomycosis case, were investigated. The fungal species were confirmed by DNA molecular analysis. A. sativum minimum inhibitory concentration (MIC) and ultrastructural effects were examined. At the MIC concentration (120 mg/mL) the micrographs indicated severe structural alterations with cell death. The antioxidant properties of the A. sativum extract were evaluated is a rat turpentine oil induced inflammation, and compared to an anti-inflammatory drug, diclofenac, and the main compound from the extract, allicin. A. sativum reduced serum total oxidative status, malondialdehyde and nitric oxide production, and increased total thiols. The effects were comparable to those of allicin and diclofenac. In conclusion, the garlic extract had antifungal effects against M. guilliermondii and R. mucilaginosa, and antioxidant effect in turpentine-induced inflammation. Together, the antifungal and antioxidant activities support that A. sativum is a potential alternative treatment in onychomycosis.


Assuntos
Antifúngicos/uso terapêutico , Antioxidantes/uso terapêutico , Alho/química , Onicomicose/tratamento farmacológico , Onicomicose/microbiologia , Extratos Vegetais/uso terapêutico , Rhodotorula/química , Saccharomycetales/química , Animais , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Benzotiazóis/química , Compostos de Bifenilo/química , Contagem de Colônia Microbiana , Sequestradores de Radicais Livres/química , Humanos , Masculino , Unhas/efeitos dos fármacos , Unhas/microbiologia , Unhas/patologia , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Picratos/química , Extratos Vegetais/farmacologia , Ratos Wistar , Rhodotorula/efeitos dos fármacos , Rhodotorula/crescimento & desenvolvimento , Rhodotorula/ultraestrutura , Saccharomycetales/efeitos dos fármacos , Saccharomycetales/crescimento & desenvolvimento , Saccharomycetales/ultraestrutura , Ácidos Sulfônicos/química
17.
World J Microbiol Biotechnol ; 35(10): 157, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31576445

RESUMO

In this study, we aimed to determine the effect of exogenous stress factors (sodium chloride as osmotic stressor, hydrogen peroxide as an inducer of oxidative stress, white light irradiation, and low temperature) on the biosynthesis of carotenoids and lipids by red yeast (Rhodotorula glutinis, R. mucilaginosa, and R. gracilis) during cultivation in media containing potato wastewater and glycerol. According to our results, the yeast were able to grow and biosynthesize lipids and carotenoids in the presence of the applied stress factors. Low temperature caused an increase in the biosynthesis of intracellular lipids and carotenoids. R. gracilis synthesized lipids (21.1 g/100 gd.w.) and carotenoids (360.4 µg/gd.w.) in greater quantities than that of other strains. Under these conditions, there was also an increase in the content of unsaturated fatty acids, especially linoleic and linolenic acids. The highest percentage of polyunsaturated fatty acid (PUFA) (30.4%) was synthesized by the R. gracilis yeast after cultivation at 20°C. Their quantity was 2.5-fold greater than that of the biomass grown in control conditions. The contribution of individual carotenoid fractions depended both on the yeast strain and the culture conditions. Induction of osmotic stress and low temperature intensified the biosynthesis of ß-carotene (up to 73.9% of the total carotenoid content). In oxidative stress conditions, yeast synthesized torulene (up to 82.2%) more efficiently than under other conditions, whereas white light irradiation increased the production of torularhodin (up to 20.0%).


Assuntos
Carotenoides/biossíntese , Meios de Cultura/metabolismo , Lipídeos/biossíntese , Rhodotorula/metabolismo , Meios de Cultura/química , Resíduos Industriais/análise , Rhodotorula/genética , Rhodotorula/crescimento & desenvolvimento
18.
Appl Biochem Biotechnol ; 189(2): 589-607, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31073981

RESUMO

AbstractThe objective of this study was to determine the possibility of simultaneous biosynthesis of lipids and carotenoids by the Rhodotorula yeast strains in media with waste glycerol and deproteinized potato wastewater and to determine the level of pollution reduction by media. On the basis of results obtained during the yeast microcultures in the Bioscreen C system, it was found that potato wastewater and glycerol can be used as components of media for Rhodotorula glutinis, Rhodotorula mucilaginosa, and Rhodotorula gracilis yeast strains. The amount of glycerol added to media higher than 10% significantly decreased the growth rate of yeast. The results of yeast culture in the laboratory shaker flasks showed a possibility of simultaneous production of lipids and carotenoids by R. glutinis, R. mucilaginosa, and R. gracilis yeast strains during cultivation in media containing only waste glycerol and deproteinized potato wastewater. A higher intracellular lipid content (approximately 15 g/100 gd.w.) was obtained for R. mucilaginosa and R. gracilis yeast biomass after cultivation in experimental media with waste glycerol and potato wastewater. In conclusion, the yeast grown in media with potato wastewater supplemented with 3% or 5% glycerol synthesized carotenoids, and their content in biomass did not exceed 230 µg/gd.w.


Assuntos
Carotenoides/biossíntese , Glicerol/química , Lipídeos/biossíntese , Rhodotorula/crescimento & desenvolvimento , Solanum tuberosum/química , Águas Residuárias
19.
Ecotoxicol Environ Saf ; 180: 63-72, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31075717

RESUMO

In the present study, a potent Aluminum (Al) resistant yeast strain CAM4 was isolated from rhizosphere soil of Rubus geoides, grown in acidic Andisols and identified as Rhodotorula mucilaginosa by 18S rRNA gene sequence analysis. The strain CAM4 was selected in terms of abiotic stress tolerance to Al, salinity and drought with multiple plant growth promoting (PGP) traits. Besides, strain CAM4 also exhibited Al removal efficiency (80-88%) from the culture medium even under combined stresses of salinity and drought. The sawdust-based formulation of strain CAM4 (sawdust-molasses 5%-PEG 1%-strain CAM4) showed higher cell viability of up to 24 weeks (8.54 log CFU g-1). Inoculation of formulated strain CAM4 significantly enhanced the various morphological and biochemical characters of Lactuca sativa grown under abiotic stress conditions. The formulated strain CAM4 also reduced the accumulation of Al in L. sativa as well that conferring Al tolerance to the plants. The study concludes that strain CAM4 could be used as a biofertilizer for healthy and safe crop production in soils, with Al toxicity as well as combined salt and drought stresses.


Assuntos
Alumínio/toxicidade , Secas , Lactuca/efeitos dos fármacos , Rhodotorula/crescimento & desenvolvimento , Salinidade , Microbiologia do Solo , Estresse Fisiológico/efeitos dos fármacos , Lactuca/crescimento & desenvolvimento , Rizosfera , Solo/química
20.
Ecotoxicol Environ Saf ; 174: 484-490, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30856560

RESUMO

Microorganisms have been widely applied to heavy metal adsorption due to their strong secretion of extracellular polymeric substances (EPS). This study explored the responses of Rhodotorula mucilaginosa (R1, a red yeast with substantial EPS supply) under Pb stress. The maximum sorption of Pb cations by R1 was ~650 mg/L. In particular, despite the declined microbial biomass, the total Pb sorption after incubation was actually elevated in the solution with high Pb concentration. At 0-1000 mg/L Pb(NO3)2 level, the longitudinal sizes of the yeast capsules increased from 2.04 to 2.90 µm. At 1500 mg/L, however, the survived yeast started to lose the membrane integrity of the cells. Meanwhile, the percentages of organic carbon contents of EPS decreased from 40% to 33% when the Pb(NO3)2 concentration raised to 2500 mg/L, confirming the incorporation of Pb2+ cations into the fungal EPS during the sorption. For the survived R1 cells, function of polysaccharides to resist Pb toxicity only worked at extremely high Pb(NO3)2 levels (>= 1500 mg/L). In contrast, proteins showed continuously enhanced ability to resist Pb toxicity, consistent with their increasing content (per cell) in the EPS. Moreover, ATR-IR spectra showed that the intensity of amide II peak at 1540 cm-1 was significantly increased, indicating elevated glutathione (GSH) in EPS. This suggested that GSH could be the critical Pb-binding component in EPS proteins. This study hence elucidated roles of polysaccharides and proteins in EPS under the toxicity caused by heavy metals.


Assuntos
Poluentes Ambientais/toxicidade , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Proteínas Fúngicas/metabolismo , Chumbo/toxicidade , Polissacarídeos/metabolismo , Rhodotorula/efeitos dos fármacos , Adsorção , Biomassa , Poluentes Ambientais/metabolismo , Chumbo/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Rhodotorula/crescimento & desenvolvimento , Rhodotorula/metabolismo , Rhodotorula/ultraestrutura
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