69 research outputs found
Yeasts as Potential Source for Prebiotic β-Glucan: Role in Human Nutrition and Health
Yeasts are a potential source for prebiotic β-glucans. This polysaccharide is characterized by d-glucose monomers linked by β-glycosidic bonds. There are significant structural differences in β-glucans depending on the source and method in which they are obtaining. This polymer is a healthier food and feed additive. Numerous beneficial effects have been attributed to this polymer, in particular immunomodulatory action. Different studies confirm safe use and applicability of β-glucans in medicine for the treatment of diseases (cancer, infections, respiratory diseases) and reduction in glucose and cholesterol levels. Many advances in the processes to obtain β-glucans have been presented, including extraction, purification, and chemical modification, aiming the biological properties and yield. One limitation of their use is the cost, so a strategic discussion of the use of yeast biomass was performed for the production of β-glucans. An extensive and systematic review was undertaken to contribute to the science and technology to obtain β-glucans and their use in different applications
Odabir plijesni Aspergillus fumigatus za proizvodnju prebiotičkih ksilooligosaharida na podlozi od šećerne trske
Sugarcane bagasse is an important lignocellulosic material studied for the production of xylooligosaccharides (XOS). Some XOS are considered soluble dietary fibre, with low caloric value and prebiotic effect, but they are expensive and not easily available. In a screening of 138 fungi, only nine were shortlisted, and just Aspergillus fumigatus M51 (35.6 U/mL) and A. fumigatus U2370 (28.5 U/mL) were selected as the most significant producers of xylanases. These fungi had low β-xylosidase activity, which is desirable for the production of XOS. The xylanases from Trichoderma reesei CCT 2768, A. fumigatus M51 and A. fumigatus U2370 gave a significantly higher XOS yield, 11.9, 14.7 and 7.9 % respectively, in a 3-hour reaction with hemicellulose from sugarcane bagasse. These enzymes are relatively thermostable at 40–50 °C and can be used in a wide range of pH values. Furthermore, these xylanases produced more prebiotic XOS (xylobiose and xylotriose) when compared with a commercial xylanase. The xylanases from A. fumigatus M51 reached a high level of XOS production (37.6 %) in 48–72 h using hemicellulose extracted from sugarcane bagasse. This yield represents 68.8 kg of prebiotic XOS per metric tonne of cane bagasse. In addition, in a biorefinery, after hemicellulose extraction for XOS production, the residual cellulose could be used for the production of second-generation ethanol.Šećerna trska je važan lignocelulozni materijal koji se koristi za ispitivanje proizvodnje ksilooligosaharida. Neki se ksilooligosaharidi upotrebljavaju u prehrani kao topljiva vlakna niske kalorijske vrijednosti s prebiotičkim učinkom, ali su skupi i teško dostupni. Od 138 plijesni u uži je izbor ušlo samo njih devet, od kojih su odabrana samo dva soja što su proizvela najviše ksilanaza, i to Aspergillus fumigatus M51 (35,6 U/mL) i A. fumigatus U2370 (28,5 u/mL). Aktivnost β-ksilozidaze u tim sojevima bila je vrlo slaba, što je pogodovalo nastanku ksilooligosaharida. Djelovanjem ksilanaza su nakon tri sata iz šećerne trske razgradnjom hemiceluloze dobivene veće količine ksilooligosaharida, i to 11,9 % s pomoću plijesni Trichoderma reesei CCT 2768; 14,7 % s pomoću A. fumigatus M51 i 7,9 % s pomoću A. fumigatus U2370. Ti su enzimi relativno termostabilni na temperaturama od 40 do 50 °C, a mogu se koristiti pri različitim pH-vrijednostima. Osim toga, u usporedbi s komercijalnom ksilanazom, ove su ksilanaze proizvele više prebiotičkih ksilooligosaharida (ksilobioze i ksilotrioze). Razgradnjom hemiceluloze izolirane iz šećerne trske pomoću ksilanaze iz plijesni A. fumigatus M51 dobivena je znatna količina (37,6 %) ksilooligosaharida nakon 48-72 sata hidrolize, što odgovara prinosu od 68,8 kg prebiotičkih ksilooligosaharida po toni šećerne trske. Osim toga, nakon izdvajanja hemiceluloze za proizvodnju ksilooligosaharida, preostali dio celuloze može se upotrijebiti u rafineriji za proizvodnju druge generacije biogoriva
Chemical inhibition of the contaminant lactobacillus fermentum from distilleries producing fuel bioethanol
The purpose of this study was to determine the Minimum Inhibitory Concentration (MIC) of pure or mixed chemicals for Saccharomyces cerevisiae and Lactobacillus fermentum in the samples isolated from distilleries with serious bacterial contamination problems. The biocides, which showed the best results were: 3,4,4' trichlorocarbanilide (TCC), tested at pH 4.0 (MIC = 3.12 mg/l), TCC with benzethonium chloride (CBe) at pH 6.0 (MIC = 3.12 mg/l) and TCC mixed with benzalkonium chloride (CBa) at pH 6.0 (MIC = 1.53 mg /l). If CBa was used in sugar cane milling in 1:1 ratio with TCC, a 8 times reduction of CBa was possible. This formulation also should be tested in fermentation steps since it was more difficult for the bacterium to develop resistance to biocide. There was no inhibition of S. cerevisiae and there were only antibiotics as an option to bacterial control of fuel ethanol fermentation by S. cerevisiae573441447FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPSem informaçã
Chemical inhibition of the contaminant Lactobacillus fermentum from distilleries producing fuel bioethanol
Applications of the hexanic fraction of Agave sisalana Perrine ex Engelm (Asparagaceae): control of inflammation and pain screening
The present study evaluated the anti-inflammatory and analgesic properties of Agave sisalana Perrine in classic models of inflammation and pain. The hexanic fraction of A. sisalana (HFAS) was obtained by acid hydrolysis followed by hexanic reflux. Anti-inflammatory properties were examined in three acute mouse models (xylene ear oedema, hind paw oedema and pleurisy) and a chronic mouse model (granuloma cotton pellet). The antinociceptive potential was evaluated in chemical (acetic-acid) and thermal (tail-flick and hot-plate test) models of pain. When given orally, HFAS (5, 10, 25 and 50 mg/kg) reduced ear oedema (p < 0.0001; 52%, 71%, 62% and 42%, respectively). HFAS also reduced hind paw oedema at doses of 10 mg/kg and 25 mg/kg (p < 0.05; 42% and 58%, respectively) and pleurisy at doses of 10 mg/kg and 25 mg/kg (41% and 50%, respectively). In a chronic model, HFAS reduced inflammation by 46% and 58% at doses of 10 mg/kg and 25 mg/kg, respectively. Moreover, this fraction showed analgesic properties against the abdominal writhing in an acetic acid model (at doses of 5-25 mg/kg) with inhibitory rates of 24%, 54% and 48%. The HFAS also showed an increased latency time in the hot-plate (23% and 28%) and tail-flick tests (61% and 66%) for the 25 mg/kg and 50 mg/kg doses, respectively. These results suggest that HFAS has anti-inflammatory and analgesic properties.26327
Improvement in RNA extraction from S. cerevisie by optimization in the autolysis and NH3 hydrolysis
Applications of the hexanic fraction of Agave sisalana Perrine ex Engelm (Asparagaceae): control of inflammation and pain screening
Influencia da contaminação por bacterias lacticas na fermentação alcoolica pelo processo de batelada alimentada
Orientador: Fumio YokoyaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de AlimentosResumo: Este trabalho foi realizado em duas etapas: uma envolvendo isolamento, taxonomia e testes de resistência ao etanol e floculação do fermento comercial, no intuito de selecionar bactérias táticas, natura!mente contaminantes de dornas de fermentação. Na segunda etapa, foi montado um sistema piloto de Saneada para realização dos ensaios de fermentação. Inoculando com uma bactéria selecionada na primeira etapa - o LactobaclIIus fermentum nº 28 , simulando-se a infecção bacteriana das dornas de fermentação nas usinas, através do processo cíclico de batelada alimentada. Para a primeira etapa, a amostragem foi feita tícleite de leyeduras", sem tratamento ácido, obtido de duas destilarias anexas no mes de agosto de 1988. A primeira - Usina Santa Adélia (Jabotícabal-SP) - apresentava problemas microbiológicos e a segunda Usina Modelo - operava normalmente. Os resultados da taxonomia demonstraram que e bactéria predominantemente encontrada foi Lactobaci!Ius fermentum (62%), seguida de LactobaciIIua murinus (9%), Lactobacillus vaccInostercus (9%), LactobaciIlus piantarum (2%) e Leuconostoc (2%). Dentre os lactobacilos houve um predomínio do tipo heterofermentativo obrigatório (85%). As cepas testadas apresentaram-se resistentes a 7% (v/v) de etanol e 63% resistiram a 10%, demonstrando adaptação ao ambiente alcoólico. A característica de floculação do fermento foi manifestada em 67% das cepas testadas. Quanto às usinas, confirmou-se que a Usina Santa Adélia apresentava maior índice de contam inação, de cepas resistentes ao etanol e de floculação do fermento comercial. Os resultados dos ensaios de fermentação demonstraram que acima Ce 4,8 g/l de acidez, expressa em ácido látlco, e a relação levedura/bactéria inferior a 0,9, as características vitais e o crescimento da levedura foram seriamente comprometidos. A produtividade de etanol (Pe) e a taxa de consumo de açúcar (Ps) sofreram queda semelhante (em torno de 54%), entre a
média dos primeiros 9 cicios e o 16° cicio, onde a acidez e a contaminação foram máximas. Isso causou a diminuição na velocidade de consumo de açúcar pela levedura, e a consequente queda na produção de etanol, devido ao excesso de acidez proveniente da contaminação bacteriana. Os parâmetros de rendimento de álcool , Yp/so e porcentagem de ART consumido, também apresentaram uma queda acentuada nos ciclos finais, servindo também como índices para avaliação da infecção na produção de etanol. O fator de conversão de açúcar consumido em etanol produzido - Yp/s não demonstrou o efeito da acidez sobre a produção de etanol, isso, foi distribuição o cálculo baseando-se no açúcar consumido pela levedura e não no disponível no sistemaAbstract: This research was carried out in 2 stages. The first stage involved isolation, taxonomy, tests of resistance to ethanol and commercial yeast flocculation tests, all aimed at selecting lactic bacteria which were natural contaminants of fermentation vats. In the second stage, a pilot system was set up to carry out fermentation assays simulating distillery conditions and using one of the bacteria's selected in the first stage. Under these conditions Lactobacillus fermentum isolated n 28 was tested, reproducing the bacterial infection of the distillery fermentation vats by way of a fed-batch process. For the first stage of experiment, concentrated yeast samples from two distilleries were obtained, without cid treatment, during August , 1388. The first distillery (Santa AdeIla - Jaboticabal, S.P.) was presenting microbiological problems, while the second (Modelo - Piracicaba, SP) was operating formally. The results of the taxonomic study showed that the predominant bacterium present woo Lactobacillus fermentum (Bet), followed by Lactobacilus murinus (9%), Lactobacillus vacclnostercus (9%), Lactobacillus plantarun (2%) and Leuconostoc (2%). Among the lactobaciIIus, the obligate he terofermentatiue types were predominant Í8BX). The strains tested were all resistant to 7% (v/u) ethanol, and 64% were resistant to 10%, demonstrating adaptation to the alcoholic environment. Flocculation of the yeast was a characteristic of 67% of the strains tested. Regarding the distilleries, the expected results were confirmed. The Santa fidélla showed a higher level of contamination, with strains more resistant to alcohol and floculation of the commercial yeast. The results of the fermentation assays, showed that both the vital characteristics and growth of the yeast were seriously undermined when the acid concentration exceeded 4,8 g/f (expressed as lactic acid) and yeast/bacteria ratio of about 0,9. The alcohol productivity (Pern) and sugar consumption ratios (Ps> suffered similar decrease (about 54%) between the average of the first 9 cycles and that of the sixteenth cycle, when the acidity and contamination were maximum. This indicated a loss in the velocity of sugar consumption by yeast, and a consequent fail in the production of ethanol, due to the excess of acidity caused by the bacteria! contamination. The parameters alcohol yield, Yp/so and the percentage of total sugars consumed also showed accentuated fails during the final cycles, and therefore could also serve as index for the evaluate some of infection in the ethanol production. The conversion factor Yp/s was not affected by the acidity. This was related to the fact that the calculations were based on the sugar consumed by the yeast, and not that available within the systemMestradoMestre em Ciência de Alimento
Estudo de diferentes fatores que influenciam o crescimento da população bacteriana contaminante da fermentação alcoolica por leveduras
Orientador: Fumio YokoyaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de AlimentosResumo: Neste trabalho foi realizado o estudo da fermentacão alcoólica do HTM (high test molasses) por leveduras de panificação contaminada com Lactobacillus fermentum CCT 1407 através do processo "fed-batch" com reciclo de células, visando simular as condições industriais, 0 estudo de inibidores do crescimento de Lactobascillus- Leuconostoc e Saccharomyces cerevisiae foi -Feito através da técnica de macrodiluicão em caldo para determinação da Concentração Minima Inibitória (CHI) do crescimento. 0 mais promissor dos produtos analisadas foi selecionado e testado no modelo de fermentação, com a adição de ewtrato de levedura para favorecer o crescimento do contaminante. Os resultados indicaram que o estudo da população mista, leveduras e bacterias 1át icas, simulou o mecanismo de infeccão bacteriana da fermentação. Após 4 a 7 ciclos de fermentação de horas cada, ocorreu o rápido cresc imento da população bacteriana inoculada no primeiro ciclo e, após 8 a 12 ciclos, a inibição das leveduras foi proeminente, provocada pelo ao aumento da acidez. 0 crescimento bacteriano foi estimulado com a adição de extrato de levedura ( í'Ái ou um con junto de 17 aminoácidos. A marte das leveduras foi acelerada pelo excesso de acides na vinha (15 g/l) Testes de cultivo puro de Lactobacillus fermentum CCT 1407 em caldo de cana a VA confirmaram que aminoácidos, quando complementados na meio. Foram essenciais para o crescimento das bactérias, e não sais, vitaminas ou açúcares como afirmaram alguns pesquisadores. Os aminoácidos devem ser os principais componentes presentes na extrato de levedura que estimulam o crescimento das bactérias láticas durante a fermentação. Dentre os aminoácidos complementados, a leucina, íso-leucina e valina foram essenciais para ? crescimento bacteriano *^cido glutâmico, alanina, cisteina, treonina, triptofano, fenilalanina, tiros i na e met ian i na most raram efeito estimulador da crescimento. A quantidade de entrato de levedura parece ser crítica no estímulo do crescimento. Concentrações acima de 600 mg/l mostraram notável aumento do crescimento bacteriano A duração do ciclo de fermentação e a velocidade de centrifugação foram fatores importantes que influenciaras? o crescimento da população bacteriana na fermentacão alcoólica. Ciclos com 20 horas foram mais estimuladores do crescimento bacteriana, do que os de 12 horas Baixas velocidades de centrifugação do fermento (870 X g) favoreceram mais o desenvdlvimento das bacterias contaminantes comparadas com altas velocidades (5000 X g) Os seguintes resultados foram encontrados com respeito a CMI em Lactobacillus fermentum e leuconostoc mesenteroides no meio a base de caldo de cana a 4% em pH 4,5: clindamícina 0,050 - 0,40 ug/ml, penicilina U ácida 0,050 - 0,50 ug/ml, sulfito de sódio 10,0 - 40,0 ug/ml e formaldeido 11,5 - 23,0 ug/ml. Dentre as formulações comerciais os ativos bromofenato com CHI de 9 - 18 ug/ml, tiocianato 1,80 - 5,0 ug/ml, e o Desflac 0,P5 - 0,50 ug/ml. A concentração de 75 mg/l de Desfloc ítriclorocarbanilida) imobiliado em alginato de cálcio, e combinado com lauril sulfato de sódio (i,6? a 5,00 mg/l) controlaram de forma eficaz o crescimento de L. fermentum na fermentação alcoólica conduzida em escala de laboratórioAbstract: Abstract: In this work, the alcoholic fermentation study of HTM (high test molasses) by baker s yeast contaminated with Lactobacillus fermentum CCT 1407 was carried out by fed-batch and cell recycle process, aimming to simulate the industry conditions. The growth inhibitors study of Lactobacillus, Leuconostoc and Saccharomyces cerevisiae was done by macrodilut ion broth technic of Minimal Inhibition Concentration (MIC) of growth. The most promissing compound was selected, and it was tested in fermentation model with added yeast extract to stimulate contaminant growth The results indicated that study of yeast and lactic acid bacteria population simulated the bacterial infection mecanism of fermentation. After 4 to 7 fermentation cycles of 20 hours each, the inoculated bacterial population started to grow very rapidly and after 8 to 12 cycles, the yeast inhibition by increased acidity was prominent. The bacterial growth was stimulated with addition of yeast extract (1%) or a group of 17 amino acids. The death of yeast was accelereted by excess of acidity of wine (15 g/L). Tests of pure culture by Lactobacillus fermentum CCT 1407 in cane broth (.4%) confirmed that amino acids added on the medium, were essential for bacterial growth, and not salts, vitamins or sugars as presumed by some investigators. The amino acids should be the main components found in yeast extract that stimulate the growth of lactic acid bacteria during fermentation. Amongst added amino acids, leucine, isoleucine and valine were essential for bacterial growth. Glutamic acid, alanine, cysteine, threonine, thiptophane, phenylalanine, tyrosine and methionine showed stimulating effect on growth. The amount of yeast extract seems to be crytical on bacterial stimulation. Concentration above 600 mg/l showed noticible increase on bacterial growth. The period of fermentation cycle and speed of centrifugation were important factors that influenced bactevial population growth in the alcoholic fermentation Cycles of 20 hours were more stimulant of bacterial growth than 12 hours. Low speed centrifugation (870 X g) stimulated more contaminant growth as compared to high speed 5000 X g) Foillowing results were shown in regard to MIC on Lactobacillus fermentum and Leuconostoc mesenteroides with cane broth medium (4%) on pH 4 5: clindamicin 0 .050-0.40 ug/ml V acid penicilin 0.050-0.20 ug/ml; sodium sulfite 10-40 ug/ml and formaldeide 11. 5-23 ug/ml. Among the comercially formulated products, the active bromofenate showed MIC of 9-18 ug/ml; tiocianate 1.2-5.0 ug/ml and Desfloc 0.25-0.50 ug/ml. Amount of 75 mg/l of Desfloc (triclorocarba-nilide) entrapped in calcium alginate and combined with sodium lauryl sulphate (2 mg/l) controlled effectively, the Lactobacillus fermentun" growth on alcoholic fermentation carried out in IaboratoryDoutoradoDoutor em Ciência de Alimento
Cell immobilization improves isomaltulose production
The Laboratory of Industrial Biotechnology at the Biological Sciences Department in Sao Paulo State University, Brazil is working to improve the technologies involved with isomaltulose production. The study evaluated enzymatic reaction parameters with the goal of improving isomaltulose production which is grown with a medium of 1% cane molasses and 0.5% yeast extract thereby using calcium alginate, glutaraldehyde and polyethyleneimine. The best results were obtained using P. rubrum immobilized pellets in calcium alginate with 705 and 60% sucrose solution. The developed technology apparently allows the reuse of the cell-containing enzymes more times compared to conventional technologies, which ultimately results in decreased costs. The researchers are also involved in alcohol and biopolymer production and seeking interested industrial collaborators
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