Comparative analysis of various sources of selenium on the growth performance and antioxidant status in broilers under heat stress / Análise comparativa de várias fontes de selênio no desempenho de crescimento e status antioxidante em frangos de corte sob estresse térmico

Abstract The supplementation of Selenium-enriched probiotics is effective in reducing oxidative stress and maintaining meat quality stability in broiler chicken especially under heat stress. An experimental study was conducted to perform Comparative analysis of Selenium yeast with inorganic Se in broilers under heat stress. A total of 120 broilers chicks of one day were assigned to 4 groups each consisting 30 chicks fed on same basal diet but different selenium sources. The basal diet of group D1 was not supplemented with Se source (Negative control), group D2 basal diet was supplemented with inorganic selenium (Sodium selenite 0.22mg/Kg starter phase and 0.15mg/Kg finisher phase), group D3 basal diet was supplemented with commercially available organic selenium (Seleno-methionine 0.22mg/Kg starter phase and 0.15mg/Kg finisher phase) and group D4 basal diet was supplemented with self-developed organic selenium (Se-enriched yeast 0.22mg/Kg starter phase and 0.15mg/Kg finisher phase). The performance parameters i.e. feed intake (FI), live body weight (BW) and FCR were not significantly (p>0.05) effected by selenium supplementation in the starter phase but were significantly (p<0.05) effected in the finisher phase. Selenium supplementation significantly (p<0.05) effected serum Se level in different supplemented groups. Higher serum Se value (58.20±0.06) was recorded in D4 group. Similarly significantly lower selenium value was recorded for D4 and higher was recorded for D1 (11.36±0.08). However lower serum Paraoxonase (PON) value was recorded for D4 (13.24±0.01) and higher for D1 (13.33±0.03). Comparatively self-developed Se enriched yeast increased the Se accumulation and improved antioxidant system. Glutathione peroxidase (GPx) was found higher in D4 (12.333±0.03) followed by D3, D2 and D1 respectively. Whereas superoxide dismutase (SOD) was significantly lower (p<0.05) in D4 (0.1437±0.003) followed by D3 (0.1457±0.002). Selenium supplementation increased the bird's survival rate. Birds fed on Se enriched yeast showed higher Se deposition and better antioxidant capacity as compared to other sources of selenium. Se-enriched yeast displayed an improved result on Se deposition in tissues, and oxidative capacity, meat tenderness and immune response level as compared to other sources of selenium.

Resumo A suplementação de probióticos enriquecidos com selênio é eficaz na redução do estresse oxidativo e na manutenção da estabilidade da qualidade da carne em frangos de corte, especialmente sob estresse por calor. Um estudo experimental foi conduzido para realizar uma análise comparativa da levedura selênio com o Se inorgânico em frangos de corte sob estresse térmico. Um total de 120 pintos de um dia foi dividido em 4 grupos, cada um consistindo de 30 pintos alimentados com a mesma dieta basal, mas com diferentes fontes de selênio. A dieta basal do grupo D1 não foi suplementada com fonte de Se (controle negativo), a dieta basal do grupo D2 foi suplementada com selênio inorgânico (selenito de sódio 0,22 mg / kg fase inicial e 0,15 mg / kg fase finalizadora), a dieta basal do grupo D3 foi suplementada com selênio orgânico disponível comercialmente (fase inicial de seleno-metionina 0,22 mg / kg e fase finalizadora de 0,15 mg / kg) e a dieta basal do grupo D4 foi suplementada com selênio orgânico autodesenvolvido (fermento enriquecido com Se 0,22 mg / kg fase inicial e 0,15 mg / kg fase finalizadora). Os parâmetros de desempenho, ou seja, consumo de ração (FI), peso corporal vivo (PC) e FCR não foram significativamente (p > 0,05) afetados pela suplementação de selênio na fase inicial, mas foram significativamente (p < 0,05) afetados na fase final. A suplementação de selênio afetou significativamente (p < 0,05) o nível de Se sérico em diferentes grupos suplementados. O maior valor de Se sérico (58,20 ± 0,06) foi registrado no grupo D4. Da mesma forma, valor de selênio significativamente menor foi registrado para D4 e maior foi registrado para D1 (11,36 ± 0,08). No entanto, um valor mais baixo de Paraoxonase (PON) sérica foi registrado para D4 (13,24 ± 0,01) e mais alto para D1 (13,33 ± 0,03). A levedura enriquecida com Se comparativamente autodesenvolvida aumentou o acúmulo de Se e melhorou o sistema antioxidante. A glutationa peroxidase (GPx) foi encontrada maior em D4 (12,333 ± 0,03) seguido por D3, D2 e ​​D1 respectivamente. Enquanto a superóxido dismutase (SOD) foi significativamente menor (p < 0,05) em D4 (0,1437 ± 0,003) seguido por D3 (0,1457 ± 0,002). A suplementação de selênio aumentou a taxa de sobrevivência da ave. Aves alimentadas com levedura enriquecida com Se apresentaram maior deposição de Se e melhor capacidade antioxidante em comparação com outras fontes de selênio. A levedura enriquecida com Se apresentou um resultado melhorado na deposição de Se nos tecidos, capacidade oxidativa, maciez da carne e nível de resposta imune em comparação com outras fontes de selênio.

Homeopathy treatment of Malassezia Pachydermatis in vitro

A common clinical occurrence in dogs is otitis externa caused by excessive growth of yeasts Malassezia pachydermatis, which can become chronic after wrong treatments, in which microbial resistance can occur. Homeopathic remedies can be considered a successful alternative, selecting the medicine through the similitude principle. Herein, 50 µL of a 1:1000 dilution of Malassezia pachydermatis suspension at 0.5 McFarland scale was used to seed the yeast into Sabouraud dextrose agar plates using a Drigalski spreader to proceed with colony unit counting. Before being seeded, the yeast suspensions were treated with 1% of different homeopathic treatments previously selected from a pilot study, which means Sulphur 6cH, Dolichos pruriens 6cH, and Kali carbonicum 6cH, being water, and succussed water used as controls. For comparison, a set of Sabouraud dextrose agar plates containing 1% Tween 80 was seeded in parallel. The treatments were made blind and evaluated in triplicate. Contaminated cultures were withdrawn. The number of colonies per plate was assessed, and smears were made from the cultures to classify yeast growth according to cytomorphology on ImageJ®software. The preliminary results show no significant effect of all tested medicines compared to the controls. High data variability was also observed, mainly in those cultures whose medium was prepared with Twin 80. In conclusion, at this point of the study, no evidence of the effects of the studied medicines on Malassezia pachydermatis growth in vitro could be identified. The analysis of cytomorphology is still in course.

Occurrence of citrus brown and black spot diseases and their control using pre-harvest approaches

Mild brown and black spot diseases symptoms were detected on citrus varieties, Valencia and Navel fruits during season 2018 in some citrus orchards at North Egypt. Collected diseased fruit samples revealed isolation of Alternaria alternata and Phyllosticta citricarpa (McAlpine) van der Aa. Some organic acids, salts and Saccharomyces cerevisiae were evaluated against the diseases incidents in vitro and in vivo. Complete growth inhibition was recorded for fungi tested at 2g/L of salicylic acid, Potassium dihydrogen phosphate, Tri-Sodium polyphosphate and 2.5 g/L of S. cerevisiae. All pre-harvest treated Valencia trees, inoculated fruits revealed no diseases symptoms up to 10 days of storage period. Meanwhile, S. cerevisiae and salicylic acid treatments had extended protective effect up to 20 days. Control strategy through spraying Valencia orange trees with yeast or some organic acids and salts as pre-harvest approaches should be taken in consideration especially these diseases began to occur in North region of Egypt.

Effect of Danggui Niantongtang on Expression of Autophagy-related Proteins LC3， Beclin1 and p62 in Rats with Adjuvant Arthritis Differentiated into Wind-damp-heat Impediment / 中国实验方剂学杂志

ObjectiveTo observe the preventive and control effects of Danggui Niantongtang against adjuvant arthritis differentiated into wind-damp-heat impediment in rats and its influences on the expression of autophagy-related proteins microtubule-associated protein 1 light chain 3 （LC3）， homolog of yeast Atg6 （Beclin1） and p62. MethodThe six-week-old male SD rats were randomly divided into the normal group， wind-damp-heat impediment model group， low-， medium-， and high-dose Danggui Niantongtang （5.67， 11.34， 22.68 g·kg-1） groups， and methotrexate （MTX， 1.35 mg·kg-1） group， with 10 rats in each group. A rat model of adjuvant arthritis was established by subcutaneous injection of inactivated Mycobacterium tuberculosis into the tail root， followed by exposure to the manual climatic box for 16 d for inducing the wind-damp-heat impediment. The drugs were administered intragastrically on the day of immunization for 28 d. The general conditions of rats were observed and the swelling degree of toes and arthritis index （AI） were detected. The pathological changes in the synovial tissues of the knee joints were observed by hematoxylin-eosin （HE） staining. The mRNA expression levels of LC3， Beclin1， and p62 in the synovial tissues were measured by real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）， followed by the assay of their protein expression by Western blot and immunohistochemistry. ResultCompared with the normal group， the wind-damp-heat impediment model group exhibited significantly increased swelling degree of toes （P<0.01）， increased AI （P<0.01）， proliferated synovial cells （P<0.01）， up-regulated LC3 and Beclin1 protein and mRNA expression （P<0.01）， and down-regulated p62 protein and mRNA expression （P<0.01） after 16， 20， 24， 28-d medication. Compared with the wind-damp-heat impediment model group， each medication group displayed alleviated toe swelling and synovial hyperplasia to different degrees， decreased mRNA and protein expression levels of LC3 and Beclin1 （P<0.01）， and increased p62 mRNA and protein expression （P<0.05，P<0.01）， with the best outcomes observed in the medium-dose Danggui Niantongtang group. ConclusionDanggui Niantongtang effectively relieves adjuvant arthritis due to wind-damp-heat impediment in rats， which may be related to its regulation of the expression of autophagy-related proteins LC3， Beclin1， and p62 and the inhibition of autophagy.

Chemical profile, anti 5-lipoxygenase and cyclooxegenase inhibitory effects of ginger (Zingiber officinale) rhizome, callus and callus treated with elicitors / Perfil químico, anti-5-lipoxigenase e efeitos inibitórios da ciclooxegenase do rizoma de gengibre (Zingiber officinale), do calo e calos tratados com elicitores

The present study investigated the chemical profiles and evaluated the inhibitory effect against 5-Lipoxygenase (5-Lox) activity for extracts of ginger rhizome, callus, and callus treated with the elicitors; yeast extract (100, 300 and 500 mg/L), glycine (100, 200 and 300 mg/L) and salicylic acid (100 and 200 mg/L). Oils and chloroform: methanol (CM) extracts were prepared by maceration in petroleum ether and CM (1:1, v/v), respectively. Chemical profiles were determined by gas chromatography/mass spectrometry (GC/MS) analysis. Oil of the callus recorded higher 5-Lox inhibitory effect (IC50 58.33±4.66 µg/mL) than the oil of rhizome (IC50168.34±15.64 µg/mL) and comparable to that of the positive control; Nordihydroguaiaretic acid (IC50 61.25±1.02 µg/mL). The chemical profile of the callus oil contained large amounts of fatty acids, mainly the unsaturated fatty acid oleic acid (31.11%) and saturated fatty acid palmitic acid (28.56%). Elicitors modified the chemical profile of the callus and ameliorated the anti-5-Lox activity of CM extract of the callus. CM extracts of callus treated with 100 and 300 mg/L yeast extract and 50 mg/L salicylic acid significantly suppressed (P ≤ 0.05) the 5-Lox activity by 33.16%, 25.46% and 16%, respectively as compared to the CM extract of untreated callus. In conclusion, ginger callus could be considered as a valuable dietary supplement in the treatment of various inflammatory disorders.

O presente estudo teve como objetivo investigar os perfis químicos e avaliar o efeito inibitório da atividade da 5-Lipoxigenase (5-Lox) em extratos de rizoma, calo e calo de gengibre tratados com os eliciadores; extrato de levedura (100, 300 e 500 mg / L), glicina (100, 200 e 300 mg / L) e ácido salicílico (100 e 200 mg / L). Extratos de óleos e clorofórmio: metanol (CM) foram preparados por maceração em éter e CM (1: 1, v / v), respectivamente. Os perfis químicos foram determinados por análise de cromatografia gasosa / espectrometria de massa (GC / MS). O óleo do calo registrou maior efeito inibitório de 5-Lox (IC50 58,33 ± 4,66 µg / mL) do que o óleo de rizoma (IC50168,34 ± 15,64 µg / mL) e comparável ao do controle positivo; Ácido nordi-hidroguaiarético (IC50 61,25 ± 1,02 µg / mL). O perfil químico do óleo de calo continha grandes quantidades de ácidos graxos, principalmente o ácido graxo insaturado ácido oleico (31,11%) e ácido graxo saturado palmítico (28,56%). Os elicitores modificaram o perfil químico do calo e melhoraram a atividade anti-5-Lox do extrato de CM do calo. Extratos de CM de calos tratados com 100 e 300 mg / L de extrato de levedura e 50 mg / L de ácido salicílico suprimiram significativamente (P ≤ 0,05) a atividade de 5-Lox em 33,16%, 25,46% e 16%, respectivamente, em comparação com o extrato de CM de calo não tratado. Em conclusão, o calo de gengibre pode ser considerado um suplemento dietético valioso no tratamento de vários distúrbios inflamatórios.

Effect of selenium yeast combined with vitamin D on thyroid hormone levels and cell apoptosis in Hashimoto′s thyroiditis rat model / 中华内分泌代谢杂志

Objective:To explore the effects of selenium yeast combined with vitamin D on thyroid hormone levels and cell apoptosis in Hashimoto′s thyroiditis rat model.Methods:Fifty-five SD rats were divided into control group( n=10) and model group( n=45). Five rats died during the modeling process, and the remaining were divided into model, selenium yeast, vitamin D, and combination therapy groups, with 10 rats in each group. Blood levels of thyroglobulin antibody(TGAb), thyroid peroxidase antibody(TPOAb), thyroid stimulating hormone(TSH), free triiodothyronine(FT 3), free thyroxine(FT 4), tumor necrosis factor α(TNF-α), interleukin(IL)-6, IL-10, IL-17, IL-23, selenium, and vitamin D3 were detected. HE and TUNEL staining were used to observe thyroid tissue morphology and cell apoptosis. Toll-like receptor(TLR)2, TLR4, myeloid differentiation protein 88(MyD88), NF-κB mRNA and protein expressions in thyroid tissue were detected by real-time PCR and Western blotting. Results:Thyroid cells were destroyed and the number of apoptotic cells was increased in model group compared with control group( P<0.05), along with increased levels of TGAb, TPOAb, TSH, TNF-α, IL-6, IL-17, and IL-23 as well as TLR2, TLR4, MyD88, NF-κB mRNA and protein expressions( P<0.05), and decreased FT 3, FT 4, IL-10, selenium, and vitamin D 3 levels( P<0.05). Thyroid cells were relatively normal and the number of apoptotic cells were reduced in the three treatment groups compared with model group( P<0.05), while TGAb, TPOAb, TSH, TNF-α, IL-6, IL-17, IL-23, TLR2, TLR4, MyD88, NF-κB levels were decreased( P<0.05), and FT 3, FT 4, IL-10, selenium, and vitamin D 3 levels were increased( P<0.05), showing the best effect in combination therapy group( P<0.05). Conclusion:Selenium yeast combined with vitamin D attenuates thyroid cell apoptosis, reduces autoimmune damage, and protects thyroid function via inhibiting TLRs/MyD88/NF-κB pathway.

Production of carboxylic acids by metabolically engineered Yarrowia lipolytica: a review / 生物工程学报

Yarrowia lipolytica is a non-conventional yeast with unique physiological and metabolic characteristics. It is suitable for production of various products due to its natural ability to utilize a variety of inexpensive carbon sources, excellent tolerance to low pH, and strong ability to secrete metabolites. Currently, Y. lipolytica has been demonstrated to produce a wide range of carboxylic acids with high efficiency. This article summarized the progress in engineering Y. lipolytica to produce various carboxylic acids by using metabolic engineering and synthetic biology approaches. The current bottlenecks and solutions for high-level production of carboxylic acids by engineered Y. lipolytica were also discussed, with the aim to provide useful information for relevant studies in this field.

The recent advances in developing gene editing and expression tools and the synthesis of natural products in Yarrowia lipolytica / 生物工程学报

Yarrowia lipolytica, as an important oleaginous yeast, has been widely used in metabolic engineering. Y. lipolytica is considered as an ideal host for the production of natural products such as terpenes, polyketides and flavonoids, due to its ability to utilize a variety of hydrophobic substrates, high stress tolerance to acid and salt, high flux of tricarboxylic acid cycle and the ability in providing abundant the common precursor acetyl-CoA. Recently, more and more tools for genetic editing, gene expression and regulation has been developed in Y. lipolytica, which facilitate the metabolic engineering of Y. lipolytica for bio-manufacturing. In this review, we summarized the recent progresses in developing gene expression and natural product synthesis in Y. lipolytica, and also discussed the challenges and possible solutions in heterologous synthesis of natural products in this yeast.

Secretos detectados de la naturaleza por Antoine van Leeuwenhoek / Detected secrets for nature by Antoine van Leeuwenhoek

Resumen Una de las obras, probablemente menos conocidas, de Antoine van Leeuwenhoek (1632-1723) es su Arcana naturae detecta (Secretos detectados de la naturaleza) publicada en su primera edición en 1695. Esta obra es una recopilación de 38 cartas sobre temas científicos y está bellamente ilustrada. Una sección notable de ella es la observación y descripción por primera vez de levaduras de la fermentación y sus experimentos sobre la generación espontánea de microorganismos.

Abstract One of the works, probably less known, of Antoine van Leeuwenhoek (1632-1723) is his Arcana naturae detecta (Detected secrets of nature) published in its first edition in 1695. This work is a compilation of 38 letters on scientific issues and it is beautifully illustrated. A notable section of the work is the observation and description for the first time of fermentation yeasts and his experiments on the spontaneous generation of microorganisms.

Tolerância de microrganismos eucariotos ao herbicida glifosato / Tolerance of eukaryotic microorganisms to glyphosate herbicide

O glifosato é um herbicida amplamente utilizado. A Organização Mundial da Saúde (OMS) reclassificou o glifosato como "provavelmente cancerígeno a humanos". A remoção do glifosato do ambiente pode ser realizada por ação enzimática microbiana. O presente trabalho enfocou o isolamento de microrganismos do solo capazes de tolerar glifosato como única fonte de carbono. As células foram isoladas em meio de cultivo mínimo suplementado com glifosato. Foram isoladas 17 bactérias, 14 fungos e 1 levedura. Foi verificada a produção da biomassa microbiana na presença e na ausência do glifosato. Um fungo (F3) e uma levedura (L1) foram selecionados após teste de tolerância ao glifosato em meio líquido. Os microrganismos toleraram o glifosato, entretanto, o metabolismo foi afetado pelo herbicida, comparado ao controle sem glifosato. Estatisticamente, o tempo de crescimento apresentou diferenças significativas. Microrganismos eucarióticos isolados de solo com glifosato são tolerantes ao composto e podem ser úteis como biorremediadores de ambientes afetados por este herbicida.(AU)

Glyphosate is one of the most widely used herbicides. The World Health Organization (WHO) has reclassified glyphosate as "probably carcinogenic to humans". Glyphosate removal from the environment can be performed by microbial enzymatic action. The present work focused on the isolation of soil microorganisms that can tolerate glyphosate as the sole carbon source. Cells were isolated in minimal culture medium supplemented with glyphosate. Microbial biomass production was verified in the presence and absence of glyphosate. Seventeen, fourteen and one bacteria, fungi and yeast were isolated, respectively. One fungus (F3) and one yeast (L1), were selected after glyphosate tolerance test in liquid medium. Eukaryotic microorganisms tolerate glyphosate, however metabolism was affected by herbicide compared to control without glyphosate. Statistically growth time showed significant differences. Eukaryotic microorganisms isolated from soil with glyphosate are tolerant to the compound and may be useful as bioremediators of environments affected by this herbicide.(AU)

Use of Saccharomyces cerevisiae-based products and effects on rumen environment and performance of sheep subjected to dietary changes / Utilização de produtos à base de Saccharomyces cerevisiae e seus efeitos sobre o ambiente ruminal e desempenho de ovinos submetidos a mudanças de dieta

ABSTRACT: Natural additives in ruminant diet optimizes animal performance by controlling or modifying the rumen fermentation pattern. The aim of this study was to evaluate the effects of using Saccharomyces cerevisiae products during abrupt changes in dietary starch concentration on ruminal pH maintenance, performance and metabolism of confined sheep. Twenty adult ewes, crossbred Texel x Corriedale(44.7±6.97 Kg BW) were divided into three groups: Control (n=6), Cultron X (yeast culture; n=7) and Cultron Pro (hydrolyzed yeast; n=7), administered at a dose of 5 g/sheep/day (10x1010CFU/g DM). The experiment lasted 20 days divided into four periods, alternating between 40 and 60% concentrate. Blood and ruminal fluid were collected at the end of each period, and daily dry matter intake was measured to determine the average daily gain (ADG). Blood tests included blood count and biochemical parameters such as glucose, urea, total plasma proteins (TPP), liver enzymes, acute phase proteins and minerals. There was an upward trend in ADG in group Cultron X compared to control in period 3. Although, ruminal pH did not differ between groups, protozoan motility was higher in animals supplemented with hydrolyzed yeast. The Cultron Pro group showed an increase in TPP in periods 3 and 4, and AST in periods 2 and 3 compared to the control group. There was no difference in other metabolites. Yeast supplementation is a potential tool in times of feeding challenge, in which yeast culture is the most effective for improving performance of confined sheep being in improving performance of confined sheep.

RESUMO: A utilização de aditivos naturais na dieta de ruminantes é uma prática que otimiza o desempenho, controlando ou modificando o padrão de fermentação ruminal. O objetivo do estudo buscou avaliar os efeitos da utilização de produtos à base de Saccharomyces cerevisiae durante mudanças na concentração de amido da dieta sobre a manutenção do pH ruminal, desempenho e metabolismo de ovinos confinados. Dessa forma, 20 fêmeas ovinas adultas mestiças das raças Texel e Corriedale (44,7±6,97 PV) foram divididas em três grupos: Controle (n=6), Cultron X (cultura de levedura; n=7) e Cultron Pro (levedura hidrolisada; n=7), administrados na dose de 5 g/ovelha/dia (10x1010ufc/g de MS). O experimento teve duração de 20 dias divididos em quatro períodos, alternando entre 40 e 60% de concentrado. Foram realizadas coletas de sangue e líquido ruminal ao final de cada período e mensuração da ingestão de matéria seca diariamente, a fim de determinar o ganho médio diário (GMD). As análises sanguíneas incluíram hemograma e parâmetros bioquímicos como glicose, ureia, proteínas plasmáticas totais (PPT), enzimas hepáticas, proteínas de fase aguda e minerais. Houve tendência de aumento no GMD no grupo Cultron X em relação ao controle no período 3. Apesar do pH ruminal não diferir entre grupos, a motilidade de protozoários foi melhor nos animais suplementados com levedura hidrolisada. O grupo Cultron Pro apresentou aumento de PPT nos períodos 3 e 4 e aumento nos níveis da enzima hepática AST nos períodos 2 e 3 em comparação ao grupo controle. Não houve diferença nos demais metabólitos. A suplementação com levedura apresentou-se como potencial ferramenta em momentos de desafio alimentar, sendo a cultura de levedura mais eficaz na melhora da performance de ovinos confinados.

Determination of Bioethanol Production from Apricot (Prunus armeniaca) Pomace

Abstract Fruit juice industry generates massive amount of lignocellulosic by-products annually which are excellent raw materials for bioethanol production. In the current study, bioethanol production from apricot (Prunus armeniaca) pomace by Kluyveromyces marxianus was investigated for the first time. Some key parameters for fermentation such as pretreatment methods, biomass and cellulase loading and time, were optimized. Kluyveromyces marxianus produced 30.09 g/L ethanol in the 20% washed apricot pomace and 120 FPU/g cellulose enzyme loading. The highest theoretical yield and Y P/S values were also observed as 94.7% and 0.50 g/g, respectively, when 15 FPU/g cellulose enzyme was used. These results depict that apricot pomace is a promising feedstock for bioethanol production.

Effect of Qiyu Sanlong Decoction in Inducing Autophagy of A549 Cells by Regulating Molecular Expression Related to Signal Axis of mTOR-Beclin1-LC3 / 中国实验方剂学杂志

Objective:To observe the effect of Qiyu Sanlong decoction （QYSL） on the expressions of key molecules in signal axis of mammalian rapamycin target protein （mTOR）/yeast Atg6 homologous （Beclin1）/ microtubule-associated protein1 light chain3 （LC3） in A549 cells. Method:With A549 cells as the research object， the effect of QYSL medicated serum on cell viability of A549 cells were detected by cell counting kit-8 （CCK-8） method. The effect of QYSL decoction on A549 cell apoptosis， autophagosome formation and the expression of autophagy markers were detected by Terminal-deoxynucleoitidyl transferase mediated nick end labeling （TUNEL） method， transmission electron microscope （TEM）， Real-time polymerase chain reaction （Real-time PCR） and Western blot. Result:QYSL medicated serum could inhibit the viability of A549 cells in a concentration-dependent manner. Compared with the blank serum group， the number of apoptotic A549 cells in the QYSL medicated serum group was significantly increased （P<0.01）， and the formation of autophagosome was significantly increased. Compared with the blank serum group， the mRNA and protein expressions of mTOR in A549 cells in the QYSL serum group were significantly decreased （P<0.01）， while mRNA and protein expressions of Beclin-1， autophagy related genes 5 （ATG5）， autophagy related genes 13 （ATG13） were significantly increased （P<0.01）. Conclusion:QYSL decoction can induce autophagy in A549 cells， and its specific mechanism may be related to the down-regulation of mTOR expression， the up-regulation of Beclin1， ATG5， ATG13 and LC3 expression， and the promotion of LC3Ⅰ conversion to LC3Ⅱ.

Effect of RIM21 gene disruption on flocculation of lager yeast / 生物工程学报

Lager yeast is the most popular yeast strain used for beer production in China. The flocculation of yeast plays an important role in cell separation at the end of fermentation. Therefore, appropriately enhancing the flocculation capability of the lager yeast without affecting its fermentation performance would be desirable for beer industry. Our previous study showed that the defect of gene RIM21 might contribute to the enhanced flocculation capability of a lager yeast G03. To further investigate the role of the RIM21 gene in flocculation of strain G03, this study constructed a RIM21-deleted mutant strain G03-RIM21Δ through homologous recombination. Deletion of RIM21 improved the flocculation capability of strain G03 during wort fermentation at 11 °C without changing its fermentation performance significantly. The expression of FLO5, Lg-FLO1 and some other genes involved in cell wall integrity pathway were up-regulated in strain G03-RIM21Δ. In addition, the disruption of RIM21 enhanced resistance of yeast cells to cell wall inhibitors. These results provide a basis for elucidating the flocculation mechanism of lager yeast under low-temperature fermentation conditions.

Screening for UV-C irradiation-enhanced transcription factors that regulate the metabolism of phenolic compounds in tomato fruit / 生物工程学报

Solanum lycopersicum phenylalanine ammonia-lyase 5 (SlPAL5) gene regulates the metabolism of phenolic compounds. The study of transcription factors that regulate the expression of SlPAL5 gene is of great significance to elucidate the regulatory mechanism underlying the biosynthesis of phenolic compounds in tomato fruit induced by UV-C irradiation. Here, yeast one-hybrid library of tomato fruit was constructed, and the yeast one-hybrid technology was used to screen the transcription factors that regulate the expression of SlPAL5, the key gene related to the synthesis of phenolic compounds in tomato fruit. As a result, a transcription factor, SlERF7, was obtained and sequenced, followed by the blast homology analysis. Further experiments confirmed that SlERF7 interacted with the promoter of SlPAL5 gene. In addition, UV-C irradiation significantly increased the expression level of SlERF7. These results indicate that SlERF7, which is regulated by UV-C irradiation, might be involved in regulating the transcription of SlPAL5, which provided foundations for further studying the regulation mechanism of the biosynthesis of phenolic compounds in tomato fruit induced by UV-C irradiation.

Exploration of yeast biodiversity and development of industrial applications / 生物工程学报

Yeast are comprised of diverse single-cell fungal species including budding yeast Saccharomyces cerevisiae and various nonconventional yeasts. Budding yeast is well known as an important industrial microorganism, which has been widely applied in various fields, such as biopharmaceutical and health industry, food, light industry and biofuels production. In the recent years, various yeast strains from different ecological environments have been isolated and characterized. Novel species have been continuously identified, and strains with diverse physiological characteristics such as stress resistance and production of bioactive compounds were selected, which proved abundant biodiversity of natural yeast resources. Genome mining of yeast strains, as well as multi-omics analyses (transcriptome, proteome and metabolome, etc.) can reveal diverse genetic diversity for strain engineering. The genetic resources including genes encoding various enzymes and regulatory proteins, promoters, and other elements, can be employed for development of robust strains. In addition to exploration of yeast natural diversity, phenotypes that are more suitable for industrial applications can be obtained by generation of a variety of genetic diversity through mutagenesis, laboratory adaptation, metabolic engineering, and synthetic biology design. The optimized genetic elements can be used to efficiently improve strain performance. Exploration of yeast biodiversity and genetic diversity can be employed to build efficient cell factories and produce biological enzymes, vaccines, various natural products as well as other valuable products. In this review, progress on yeast diversity is summarized, and the future prospects on efficient development and utilization of yeast biodiversity are proposed. The methods and schemes described in this review also provide a reference for exploration of diversity of other industrial microorganisms and development of efficient strains.

A highly sensitive yeast cell sensor constructed by overlap PCR was used to evaluate genotoxic compounds / 中国药科大学学报

@#pdr5 and snq2 gene knockout was constructed by overlap PCR, and the effects of pdr5 and snq2 mutations on the accuracy and sensitivity of RNR2 promoter-regulated yeast cell sensors in detecting genotoxic compounds were studied. The yeast cell sensors of wild-type, single-gene mutation of pdr5, single-gene mutation of snq2, and double-gene mutation of pdr5 and snq2 were studied. The cell growth inhibition and the fluorescence induction factor of the yeast cell sensors exposed to a series of concentrations of methyl methanesulfonate(MMS), ethyl methanesulfonate(EMS), cisplatin, 4-nitroquinoline-N-oxide(4NOQ), 5-fluorouracil(5-FU), hydroxyurea, salicylic acid and glucose solution were investigated. The results showed that overlap PCR method could efficiently construct the mutant yeast cell sensor. The accuracy of cell sensors of single-gene mutation of snq2 and double-gene mutation of pdr5 and snq2 were both 100%, higher than that of cell sensors of wild-type and single-gene mutation of pdr5 (87.5%). The yeast cell sensor of double-gene mutation of pdr5 and snq2 showed the highest sensitivity in detecting genotoxicity. This study provides guidance for the construction of high accuracy and sensitivity yeast cell sensor, and foundation for further functional research of yeast cell membrane transporter gene pdr5 and snq2.

Enhancement of ethanol production efficiency in repeated-batch fermentation from sweet sorghum stem juice: effect of initial sugar, nitrogen and aeration

BACKGROUND: Ethanol concentration (PE), ethanol productivity (QP) and sugar consumption (SC) are important values in industrial ethanol production. In this study, initial sugar and nitrogen (urea) concentrations in sweet sorghum stem juice (SSJ) were optimized for high PE (≥10%, v/v), QP, (≥2.5 g/L·h) and SC (≥90%) by Saccharomyces cerevisiae SSJKKU01. Then, repeated-batch fermentations under normal gravity (NG) and high gravity (HG) conditions were studied. RESULTS: The initial sugar at 208 g/L and urea at 2.75 g/L were the optimum values to meet the criteria. At the initial yeast cell concentration of ~1 × 108 cells/mL, the PE, QP and SC were 97.06 g/L, 3.24 g/L·h and 95.43%, respectively. Repeated-batch fermentations showed that the ethanol production efficiency of eight successive cycles with and without aeration were not significantly different when the initial sugar of cycles 2 to 8 was under NG conditions (~140 g/L). Positive effects of aeration were observed when the initial sugar from cycle 2 was under HG conditions (180­200 g/L). The PE and QP under no aeration were consecutively lower from cycle 1 to cycle 6. Additionally, aeration affected ergosterol formation in yeast cell membrane at high ethanol concentrations, whereas trehalose content under all conditions was not different. CONCLUSION: Initial sugar, sufficient nitrogen and appropriated aeration are necessary for promoting yeast growth and ethanol fermentation. The SSJ was successfully used as an ethanol production medium for a high level of ethanol production. Aeration was not essential for repeated-batch fermentation under NG conditions, but it was beneficial under HG conditions.

Biosurfactant produced by Candida utilis UFPEDA1009 with potential application in cookie formulation

BACKGROUND: Biosurfactants are biomolecules that have the potential to be applied in food formulations due to their low toxicity and ability to improve sensory parameters. Considering the ability of yeasts to produce biosurfactants with food-friendly properties, the aim of the present study was to apply a biosurfactant produced by Candida utilis in the formulation of cookies. RESULTS: The biosurfactant was obtained with a yield of 24.22 ± 0.23 g/L. The characterization analysis revealed that the structure of a metabolized fatty acid with high oleic acid content (68.63 ± 0.61%), and the thermogravimetric analysis demonstrated good stability at temperatures lower than 200°C, potential for food applications. The biosurfactant also exhibited satisfactory antioxidant activity at concentrations evaluated, without cytotoxic potential for cell strains, L929 and RAW 264.7, according to the (3-(4,5-dimethylthiazol-2- yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The incorporation of the surfactant into the dough of a standard cookie formulation to replace animal fat was carried out, achieving a softer, spongier product without significantly altering the physical and physicochemical properties or energy value. CONCLUSION: The thermal stability and antioxidant activity of the biosurfactant produced by C. utilis were verified, besides the positive contribution in the texture analysis of the cookies. Therefore, this biomolecule presents itself as a potential ingredient in flour-based sweet food formulations.

Efecto de Candida norvegensis sobre la degradabilidad ruminal de rastrojo de maíz y el crecimiento de corderos / Effect of Candida norvegensis on ruminal degradation of corn stover and on growth performance of lambs

Resumen Los probióticos favorecen el desarrollo de microorganismos benéficos en el rumen, lo que incrementa la digestibilidad de los nutrientes y mejora el desempeño productivo de los rumiantes; con esto, se tiene la posibilidad de utilizar ingredientes como el rastrojo de maíz de relativo bajo valor nutritivo, pero altamente disponible en algunos lugares a bajo precio. Convencionalmente, se utilizan como probióticos las levaduras Saccharomyces, aunque existen reportes sobre el uso de cepas autóctonas, como Candida norvegensis. El objetivo de este estudio fue evaluar los efectos del probiótico de Candida norvegensis en la degradabilidad ruminal in situ de rastrojo de maíz y en el comportamiento productivo de ovinos en crecimiento. La levadura Candida norvegensis (cepa Levazoot 15) [0 g (T1) y 5 g (T2)] se usó para determinar la degradación ruminal in situ (DRMS), del rastrojo de maíz, en 3 vacas canuladas ruminalmente por medio de la técnica de la bolsa de poliéster. No hubo efecto de la levadura (P > 0.05) para la fracción (a), (b) y (a+b); pero la degradabilidad efectiva al 1 %/h y 5 %/h de recambio ruminal fue mayor para T2 (P < 0.05). En un segundo experimento, 32 corderos se asignaron al azar a corrales individuales por 105 d para evaluar 4 dietas que difirieron en la proporción de concentrado/ forraje: T1 = 75:25, T2 = 75:25, T3 = 50:50, y T4 = 25:75. A excepción de T1, las dietas fueron suplementadas con Candida norvegensis, a razón de 15 mL/kg de peso vivo, equivalente a 5 g/d de levadura en base seca. Los ovinos en la dieta con 75 % de concentrado más la levadura (T2) presentaron mayor ganancia de peso, y mejor conversión alimenticia (P < 0.05). Se concluye que Candida norvegensis mostró efectos benéficos en la degradabilidad ruminal y en el desarrollo de corderos.

Abstract Probiotics assist in the development of beneficial microorganisms in the rumen that increase digestibility of nutrients and improves the productive performance of ruminants; it also has the possibility of using ingredients as corn stover of relatively low nutritional value, but available in some places at low prices. Saccharomyces yeasts are conventionally used as pro biotics and there are reports that use native strains such as Candida norvegensis. The objective of this study was to evaluate the effects of the probiotic of Candida norvegensis on the in situ ruminal dry matter degradability of corn stover and on the productive performance of growing lambs. In the first experiment, the yeast Candida norvegensis (strain Levazoot 15) [0 g (T1)] and 5 g (T2) was used to determine the in situ ruminal dry matter degradation (RDMD) of the corn stover in 3 cows with cannulas in the rumen, which was determined by the polyester bag technique. There was no effect of yeast (P > 0.05) on fraction (a), (b) and (a+b). However, the effective degradability at 1 %/h and 5 %/h of ruminal turnover was higher in T2 (P < 0.05). In the second experiment, 32 lambs were randomly assigned to individual pens for 105 d to evaluate 4 diets that differed in the proportion of concentrate: forage: T1 = 75: 25, T2 = 75:25; T3 = 50: 50, and T4 = 25: 75. With the exception of T1, the diets were supplemented with Candida norvegensis at 15 mL/kg of live weight, equivalent to 5 g/d of yeast in dry matter basis. The lambs in the diet with 75 % of concentrate plus the yeast (T2) showed greater weight gain and best feed conversion (P < 0.05). It is concluded that Candida norvegensis showed beneficial effects on ruminal degradability and on the growth of lambs.