Production of probiotic Saccharomyces boulardii in parboiled rice effluent and evaluation of bioremediation

Brazil produced 12.2 million tons of paddy rice in 2013/2014, and the south region was responsible for 60% of the production. The parboiled rice represents 50% of the national rice exports and about 20% of the total rice sold in Brazil. During the parboiling process are generated 2 liters of effluent per kilo of processed grain, generating large volumes of effluent which contains nutrients such as nitrogen and phosphorus, and organic matter. The treatment methodologies used for the treatment of this effluent are aerobic and anaerobic lagoons, activated sludge, chemical precipitation and UASB reactors. Cultivation of yeasts in wastewater has been used as a treatment technique while generating biomass that can be used as probiotic or unicellular protein source. The yeast Saccharomyces boulardii is able to grow in parboiled rice effluent when it is supplemented with extra carbon source. The aim of this study was to evaluate the use of Saccharomyces boulardii on treatment of parboiled rice effluent and biomass production. Trials were carried out for the medium selection to Saccharomyces boulardii cultivation, testing the addition of sucrose or glycerol by-product of biodiesel industry into parboiled rice effluent, collected in a rice processing industry. The best results obtained were on cultivation in effluent supplemented with 1% sucrose, generating 2.4 x 108 CFU.mL-1 of cell viability and phosphorus, nitrogen and COD removal of 72%, 50% and 56%, respectively, after 24 h of culture. After medium selection, the cell growth, yeast biomass production and its influence on the reduction of environmental parameters was analyzed in bioreactor. After 48 h of culture, it was produced 3.8 g L-1 of biomass and 1.8 x 10 11 CFU. L-1. The removal efficiency was 74% for COD and 78% for phosphorus, reaching the phosphorus removal rates required by Conselho Estadual do Meio Ambiente (CONSEMA 128/06). Furthermore, the produced dry yeast biomass and cell viability reached would allow to obtain sufficient probiotics to add to 36 tons of feed for each ton of processed grain. These results show the advantages of Saccharomyces boulardii cultivation in parboiled rice effluent supplemented with sucrose as a treatment system and production of probiotic.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPESO Brasil produziu 12,2 milhões de toneladas de arroz em casca na safra 2013/2014, sendo a região sul responsável por 60% da produção. O arroz parboilizado representa 50% das exportações nacionais de arroz e aproximadamente 20% do arroz total comercializado no Brasil. No processo de parboilização, são gerados 2 L de efluente para cada quilograma de grão processado, gerando grandes volumes de efluente que contém nutrientes, como nitrogênio e fósforo, e matéria orgânica. As metodologias de tratamento utilizadas para o tratamento deste efluente são as lagoas aeróbias e anaeróbias, lodos ativados, precipitação química e reatores UASB. O cultivo de leveduras em efluentes tem sido empregado como forma de tratamento, gerando simultaneamente biomassa que pode ser usada como probiótico ou fonte de proteína unicelular. A levedura Saccharomyces boulardii é capaz de crescer em efluente de arroz parboilizado quando este é suplementado com uma fonte extra de carbono. O objetivo deste estudo foi avaliar o uso de Saccharomyces boulardii no tratamento do efluente de arroz parboilizado e a produção de biomassa. Realizaram-se ensaios para a seleção de um meio de cultivo de Saccharomyces boulardii, testando a adição de sacarose ou glicerol de biodiesel ao efluente da parboilização de arroz, coletado em uma indústria de beneficiamento de arroz. Os melhores resultados obtidos foram no cultivo em efluente suplementado com 1% de sacarose, que gerou viabilidade celular de 2,4 x 108 UFC.mL-1 e a remoção de 72% do fósforo, 50% do nitrogênio (N-NTK) e 56% da demanda química de oxigênio (DQO) em 24 h de cultivo. A partir do meio de cultivo selecionado, analisou-se em biorreator o crescimento e a produção de biomassa da levedura e sua influência na redução de parâmetros ambientais. Após 48 h de cultivo, foi produzido 3,8 g.L-1 de biomassa e 1,8 x 10 11 UFC. L-1. A eficiência de remoção foi de 74% da DQO e 78% do fósforo, alcançando as taxas de remoção de fósforo estabelecidas pelo Conselho Estadual do Meio Ambiente (CONSEMA 128/06). Além disso, a biomassa seca produzida e a viabilidade celular alcançada permitiriam obter probiótico suficiente para adicionar a 36 toneladas de ração a cada tonelada de grão processado. Estes resultados ressaltam os benefícios do cultivo de Saccharomyces boulardii em efluente de arroz parboilizado suplementado com sacarose como sistema de tratamento e produção de probiótico

Probiotic effect of Pichia pastoris X-33 produced in parboiled rice effluent and YPD medium on broiler chickens.

In a previous paper we showed that the yeast Pichia pastoris X-33 grown in parboiled rice effluent supplemented with glycerol byproduct from the biodiesel industry improved the quality of the effluent. In this paper we show the validation of this yeast (PPE) as probiotic for broilers. Its effect on feed efficiency and immunomodulation was compared with the same yeast grown in yeast peptone dextrose medium (PPY), with Saccharomyces boulardii (SBY) and with the controls fed unsupplemented feed (CON). One-day-old female chicks were vaccinated against infectious bursal disease (IBD) and the titers of anti-IBD antibodies were measured by ELISA. PPE group had the highest mean titres on days 14 and 28 (p<0,05), and at 28 days, 64% of the animals showed seroconvertion. The PPE group also showed the best weight gains at 42 days of age, that, on days 7, 14 and 21 were 19%, 15%, and 8.7% higher, respectively, than the control group. The best feed conversion, 8.2% higher than the control group, was obtained by PPY at 42 days. Histopathological studies did not detect any undesirable effects in the supplemented animals. We concluded that Pichia pastoris X-33 when grown in effluents of the rice parboiling industry supplemented with glycerol byproduct from the biodiesel has probiotic properties for poultry

MURAL G-BIOTEC

UNIVERSIDADE FEDERAL DE PELOTA

Average weight gain and feed conversion means of groups at 1, 7, 14, 21, 28, 35 and 42 days old.

<p>Average weight gain and feed conversion means of groups at 1, 7, 14, 21, 28, 35 and 42 days old.</p

Mean titers of anti-IBD antibodies by ELISA.

<p>CON: Control; SBY: <i>S</i>. <i>boulardii</i>; PPE: <i>P</i>. <i>pastoris</i> effluent; PPY: <i>P</i>. <i>pastoris</i> YPD. Different letters signify the mean statistical differences on the day (p<0.05).</p

Probiotic effect of <i>Pichia pastoris</i> X-33 produced in parboiled rice effluent and YPD medium on broiler chickens - Fig 3

<p>Histological study showing normal hepatocyte and portal vein of the groups (a) CON, (b) SBY, (c) PPE and (d) PPY. H&E (0bj 10x).</p

Percentage of positive sera and sera with titers above 1000 of anti-IBD antibodies in chicks vaccinated at one day of age.

<p>Percentage of positive sera and sera with titers above 1000 of anti-IBD antibodies in chicks vaccinated at one day of age.</p

Probiotic effect of <i>Pichia pastoris</i> X-33 produced in parboiled rice effluent and YPD medium on broiler chickens - Fig 2

<p>Histological study showing normal splenic tissue of groups (a) CON, (b) SBY, (c) PPE and (d) PPY. H&E (0bj 10x).</p