Influence of Mode of Fermentation on Production of Polygalacturonase by a Novel Strain of Streptomyces lydicus

Pokušalo se proizvesti različite pektinolitičke enzime submerznim uzgojem s pomoću aktinomicete Streptomyces lydicus. Određena je aktivnost poligalakturonaze i pektin-liaze u supernatantu, ali je utvrđeno da soj nije uspio proizvesti pektin-esterazu. Istražena je proizvodnja poligalakturonaze submerznim uzgojem, uzgojem u polučvrstoj i na čvrstoj podlozi. Svi su pokusi provedeni u statičnoj kulturi i na tresilici. Uzgoj na statičnoj čvrstoj podlozi dao je najbolje rezultate. Kao čvrsta podloga upotrijebljeni su razni poljoprivredni otpaci, a najbolji rezultati postignuti su s pšeničnim posijama.Production of different pectinolytic enzymes was attempted using the actinomycete strain Streptomyces lydicus in submerged fermentation. Polygalacturonase and pectin lyase activities were detected in the culture supernatant, but the strain was not able to produce pectin esterase. Polygalacturonase production was studied in submerged, slurry-state and solid-state fermentation systems. All the experiments were carried out under static and shaking conditions. Solid-state fermentation under static condition was found to be promising. Various agroindustrial residues were tried as substrates for solid-state fermentation. Wheat bran was proved to be the best substrate

Statističko optimiranje proizvodnje α-galaktozidaze submerznim uzgojem aktinomicete Streptomyces griseoloalbus primjenom metodologije odzivnih površina

α-Galactosidase production by a novel actinomycete strain Streptomyces griseoloalbus in shake flask culture was optimized using response surface methodology. Screening of variables to find their relative effect on α-galactosidase production was done using Plackett-Burman design. Out of the eleven factors screened, salinity, magnesium sulphate and temperature were found to influence the enzyme production significantly. The optimal levels of these variables and the effect of their mutual interactions on enzyme production were determined using Box-Behnken design. The interaction between salinity and magnesium sulphate concentration was found to enhance α-galactosidase production, whereas temperature exhibited an influence independent of the other two factors. Using this statistical optimization method, the α-galactosidase production was increased from 17 to 50 U/mL.Primjenom metodologije odzivnih površina optimirana je proizvodnja α-galaktozidaze s pomoću novog soja aktinomiceta Streptomyces griseoloalbus u pokusima na tresilici. Primjenom Plackett-Burmanova statističkog plana ispitan je utjecaj varijabli na proizvodnju α-galaktozidaze. Od jedanaest ispitanih faktora, na proizvodnju enzima bitno su utjecali salinitet, koncentracija magnezijeva sulfata i temperatura. Optimalne vrijednosti tih varijabli i njihovo uzajamno djelovanje na proizvodnju enzima određeno je primjenom Box-Behnken statističkog plana. Međusobnim utjecajem saliniteta i koncentracije magnezijeva sulfata poboljšana je proizvodnja α-galaktozidaze, za razliku od temperature čiji utjecaj nije ovisio o ta dva faktora. Primjenom takva postupka proizvodnja α-galaktozidaze povećana je sa 17 na 50 U/mL

Novel process for the simultaneous extraction and degumming of banana fibers under solid-state cultivation Novo processo para a extração e simultânea degomagem de fibras de banana

Various process parameters for the production of polygalacturonase by Streptomyces lydicus under solid-state fermentation were optimized. The optimum particle size of wheat bran for polygalacturonase production was in the range of 500-1000 µm. Initial moisture content of 70% was found to be the optimum for enzyme production. The most suitable inoculum size was 1.25 x 10(5) CFU/mL and the optimum incubation temperature was 30ºC. Addition of carbon sources resulted in 37% increase in enzyme yield (425 U/g), whereas no significant enhancement was obtained on nitrogen supplementation. Maximum enzyme yield was recorded at 72 h. When compared to the initial production medium (108.5 U/g), the enzyme yield was 3.9 fold after optimization. Solid-state fermentation was effectively employed to develop a novel process for the simultaneous extraction and degumming of banana fibers. Streptomyces lydicus was allowed to grow on wheat bran medium in which banana leaf sheath pieces were incorporated and the fiber bundles were separated after a two-step fermentative process.<br>Vários parâmetros de processo de produção de poligalacturonase por Streptomyces lydicus por fermentação em estado sólido foram otimizados. O tamanho ótimo de partícula de farelo de trigo para a produção de poligalacturonase esteve na faixa de 500 a 1000 mm. O teor inicial de umidade de 70% foi o melhor para a produção da enzima. O inóculo inicial mais adequado foi de 1,25 x 10(5) UFC/mL e a temperatura ótima de incubação foi 30ºC. A adição de fontes de carbono resultou em aumento de 37% no rendimento da enzima (425U/g), enquanto que a suplementação com nitrogênio não melhorou o rendimento. O rendimento máximo da enzima foi obtido em 72h. A otimização resultou em um aumento de 3,9 vezes na quantidade de enzima produzida inicialmente (108,5U/g). A fermentação em estado-sólido foi eficiente para o desenvolvimento de um novo processo de extração e simultânea degomagem. Streptomyces lydicus foi cultivado em meio de farelo de trigo acrescentado de fragmentos de folhas de banana, sendo os feixes de fibras separados após um processo de fermentação em dois passos

Statistical Optimization of α-Galactosidase Production in Submerged Fermentation by Streptomyces griseoloalbus Using Response Surface Methodology

α-Galactosidase production by a novel actinomycete strain Streptomyces griseoloalbus in shake flask culture was optimized using response surface methodology. Screening of variables to find their relative effect on α-galactosidase production was done using Plackett-Burman design. Out of the eleven factors screened, salinity, magnesium sulphate and temperature were found to influence the enzyme production significantly. The optimal levels of these variables and the effect of their mutual interactions on enzyme production were determined using Box-Behnken design. The interaction between salinity and magnesium sulphate concentration was found to enhance α-galactosidase production, whereas temperature exhibited an influence independent of the other two factors. Using this statistical optimization method, the α-galactosidase production was increased from 17 to 50 U/mL