Screening of yeasts for production of xylitol fromd-xylose and some factors which affect xylitol yield inCandida guilliermondii

The ability to convertd-xylose to xylitol was screened in 44 yeasts from five genera. All but two of the strains produced some xylitol with varying rates and yields. The best xylitol producers were localized largely in the speciesCandida guilliermondii andC. tropicalis. Factors affecting xylitol production by a selectedC. guilliermondii strain, FTI-20037, were investigated. The results showed that xylitol yield by this strain was affected by the nitrogen source. Yield was highest at 30–35°C, and could be increased with decreasing aeration rate. Using high cell density and a defined medium under aerobic conditions, xylitol yield byC. guilliermondii FTI-20037 from 104 g/ld-xylose was found to be 77.2 g/l. This represented a yield of 81% of the theoretical value, which was computed to be 0.9 mol xylitol per mold-xylose

Previous notes: evaluation of the antagonistic effect of Lactobacillus species on Listeria monocytogenes in vitro

Listeria monocytogenes, agente causador da listeriose, é de grande importância para a indústria alimentícia, pois esta bactéria é capaz de proliferar-se em ambientes refrigerados, condições em que normalmente são estocados os alimentos. Os indivíduos acometidos por listeriose podem contrair infecção intrauterina, meningite e septicemia. A incidência de listeriose é baixa, mas especial atenção lhe tem sido dada devido a sua alta taxa de mortalidade e às seqüelas deixadas nos indivíduos, uma vez que esta infecção afeta o sistema nervoso central. Tendo em vista os recentes avanços no emprego de microrganismos probióticos contra espécies patogênicas, o presente trabalho teve como objetivo verificar o efeito antagônico de espécies de Lactobacillus compreendendo L. casei subsp. pseudoplantarum (30b e 30c), L. plantarum (11fb, 22c e 41b), L. reuteri (18fa e 19fa) e L. delbrueckii subsp. delbrueckii (17fb) sobre o desenvolvimento de Listeria monocytogenes in vitro. O acompanhamento da ação das possíveis substâncias inibitórias presentes no sobrenadante dos cultivos de Lactobacillus sobre a espécie patogênica foi conduzido por meio da técnica do ágar spot test e turbidimetria. Os resultados revelaram que as cepas de Lactobacillus testadas isoladamente, bem como o pool constituído pelas oito cepas, demonstraram atividade bacteriostática sobre L. monocytogenesListeria monocytogenes, an agent responsible for listeriosis, is of great importance in the food industry because of its ability to proliferate in cooled environments at temperatures normally used for food storage. Listeriosis may appear as uterine infection, meningitis and septicemia. Although listeriosis is of rather low incidence, it has received special attention because the infection affects the central nervous system, having a high mortality rate or leaving serious neurological sequels in surviving victims. With the recent advances concerning the action of probiotic microorganisms against pathogenic species, the present work aimed at studying the antagonistic effect of L. casei subsp. pseudoplantarum (30b and 30c), L. plantarum (11fb, 22c and 41b), L. reuteri (18fa and 19fa), L. delbrueckii subsp. delbrueckii (17fb) on the development of Listeria monocytogenes in vitro, employing spot test and optical density techniques. The results showed a bacteriostatic effect exerted by the Lactobacillus strains on L. monocytogenes, tested either individually or as a pool of all the eight strain

Research Article Probiotic Therapy: A Promising Strategy for the Control of Canine Hookworm

Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Canis familiaris is a domestic animal which plays an important role as a pet; however, it is very likely to develop diseases characterized by high morbidity and mortality. In this sense, there are some Ancylostomatidae species that can lead to anemia, weight loss, and abdominal pain.Therefore, the treatment with allopathic drugs is essential for eliminating the parasitism.However, the increasing occurrence of resistance to allopathic treatments stimulates the search for new therapeutic inputs, among which the probiotics stand out and are able to positively alter the intestinal microbiota and exert immunomodulatory effect. Therefore, the present study aimed to evaluate the applicability of using species of Lactobacillus (L. acidophilus ATCC 4536, L. plantarum ATCC 8014, and L. delbrueckii UFV H2B20) to control canine ancylostomiasis. A probiotic preparation containing 1 × 106 CFU of each strain was administered to 10 naturally infected animals, on alternate days for 28 days. It was observed that the treatment with the probiotic preparation led to a significant reduction in EPG of feces (88.83%

Probiotic Therapy: A Promising Strategy for the Control of Canine Hookworm

430413Made available in DSpace on 2019-09-11T20:51:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2013Canis familiaris is a domestic animal which plays an important role as a pet; however, it is very likely to develop diseases characterized by high morbidity and mortality. In this sense, there are some Ancylostomatidae species that can lead to anemia, weight loss, and abdominal pain. Therefore, the treatment with allopathic drugs is essential for eliminating the parasitism. However, the increasing occurrence of resistance to allopathic treatments stimulates the search for new therapeutic inputs, among which the probiotics stand out and are able to positively alter the intestinal microbiota and exert immunomodulatory effect. Therefore, the present study aimed to evaluate the applicability of using species of Lactobacillus (L. acidophilus ATCC 4536, L. plantarum ATCC 8014, and L. delbrueckii UFV H2B20) to control canine ancylostomiasis. A probiotic preparation containing 1 × 106 CFU of each strain was administered to 10 naturally infected animals, on alternate days for 28 days. It was observed that the treatment with the probiotic preparation led to a significant reduction in EPG of feces (88.83%/ P < 0.05), as well as an increase in leukocyte and lymphocyte counts, highlighting the potential use of Lactobacillus species in the control of canine ancylostomiasis. © 2013 Matheus Diniz Gonçalves Coêlho et al.Coêlho, M.D.G., FUNVIC, Faculdade de Pindamonhangaba, Laboratório de Parasitologia, Rodovia Presidente Eurico Gaspar Dutra s/n-Km 99, Pinhão do Una, 12422-970 Pindamonhangaba, SP, BrazilCoêlho, F.A.D.S., Universidade de Taubaté, Campus Do Bom Conselho, Laboratório de Parasitologia, Avenida Tiradentes 500, Centro, 12030-180 Taubaté, SP, BrazilMancilha, I.M.D., Universidade de São Paulo, Escola de Engenharia de Lorena, Laboratório de Probióticos, Estrada Municipal do Campinho s/n, 12602-810 Lorena, SP, Brazi

Biotechnological Utilization of Biodiesel-Derived Glycerol for the Production of Ribonucleotides and Microbial Biomass

Ten yeast strains were evaluated concerning their capabilities to assimilate biodiesel-derived glycerol in batch cultivation. The influence of glycerol concentration, temperature, pH and yeast extract concentration on biomass production was studied for the yeast selected. Further, the effect of agitation on glycerol utilization by the yeast Hansenula anomala was also studied. The yeast H. anomala CCT 2648 showed the highest biomass yield (0.30 g g(-1)) and productivity (0.19 g L-1 h(-1)). Citric acid, succinic acid, acetic acid and ethanol were found as the main metabolites produced. The increase of yeast extract concentration from 1 to 3 g L-1 resulted in high biomass production. The highest biomass concentration (21 g L-1), yield (0.45 g g(-1)) and productivity (0.31 g L-1 h(-1)), as well as ribonucleotide production (13.13 mg g(-1)), were observed at 700 rpm and 0.5 vvm. These results demonstrated that glycerol from biodiesel production process showed to be a feasible substrate for producing biomass and ribonucleotides by yeast species.Coordenacao de Aperfeicoamento de Pessoal de Nivel SuperiorCoordenacao de Aperfeicoamento de Pessoal de Nivel SuperiorConselho Nacional de Desenvolvimento Cientifico e TecnologicoConselho Nacional de Desenvolvimento Cientifico e Tecnologic

Improvement of biotechnological xylitol production by glucose during cultive of Candida guilliermondii in sugarcane bagasse hydrolysate

The effect of glucose on xylose-to-xylitol bioconversion by Candida guilliermondii was examined by adding it to sugarcane bagasse hydrolysate medium to obtain different glucose:xylose ratios (1:25, 1:12, 1:5 and 1:2.5). Under experimental conditions, increasing glucose:xylose ratio improved the assimilation of the xylose present in the hydrolysate by yeast, resulting in biomass increase, and in the formation of xylitol and glycerol/ethanol by-products. Maximum values of xylitol yield (0.59 g g-1) and volumetric productivity (0.53 g l-1.h-1) were obtained with glucose:xylose ratio of 1:5, resulting in the higher conversion efficiency (64.3%)

Improvement of biotechnological xylitol production by glucose during cultive of Candida guilliermondii in sugarcane bagasse hydrolysate

The effect of glucose on xylose-to-xylitol bioconversion by Candida guilliermondii was examined by adding it to sugarcane bagasse hydrolysate medium to obtain different glucose:xylose ratios (1:25, 1:12, 1:5 and 1:2.5). Under experimental conditions, increasing glucose:xylose ratio improved the assimilation of the xylose present in the hydrolysate by yeast, resulting in biomass increase, and in the formation of xylitol and glycerol/ethanol by-products. Maximum values of xylitol yield (0.59 g g-1) and volumetric productivity (0.53 g l-1.h-1) were obtained with glucose:xylose ratio of 1:5, resulting in the higher conversion efficiency (64.3%).O efeito da glicose na bioconversão de xilose em xilitol por Candida guilliermondii foi avaliado em hidrolisado hemicelulósico de bagaço de cana com diferentes relações glicose:xilose (1:25, 1:12, 1:5 and 1:2,5). Sob as condições experimentais, o aumento da relação glicose:xilose favoreceu a assimilação da xilose presente no hidrolisado, resultando em aumento da biomassa celular e aumento da formação de xilitol e dos sub-produtos glicerol e etanol. Os valores máximos do fator de conversão de xilose em xilitol (0,59 g g-1) e da produtividade volumétrica de xilitol (0,53 g l-1.h-1) foram obtidos com a relação glicose:xilose 1:5, resultando na maior eficiência de conversão (64,3%)

Avaliação do comportamento de um substrato sintético e de um efluente de suinocultura no tratamento anaeróbio de reatores uasb

O presente trabalho teve como objetivo avaliar o desempenho de reatores UASB alimentados com efluente natural de suinocultura (controle) e substrato sintético, empregando-se dois níveis de cargas biológicas para cada substrato (0,2 e 0,4 ngQO.KgS VT'1.d'1), com a finalidade de avaliar o uso de substrato sintético como substituto ao efluente natural de suinocultura, em experimentos onde seja difícil sua utilização. Os resultados mostraram que o substrato sintético apresentou um comportamento bastante similar ao controle, observando-se que os reatores alcançaram o regime permanente após aproximadamente 40-45 dias de operação. Para ambos os substratos, quanto maior a carga orgânica volumétrica aplicada, menor a eficiência de remoção de DQO alcançada. A similaridade no comportamento, tanto em relação a remoção de matéria orgânica, quanto a estabilidade do sistema, aponta para a possibilidade da utilização de substrato sintético em experimentos de avaliação de sistemas de tratamento de efluente de suinocultura.The present work aimed to evaluate the performance of UASB reactors fed with natural swine wastewater (control) and a synthetic media, useing two levels of biological loading rate for each media (0,2 and 0,4 kgCOD.kg VTS'1.d'1), with the purpose of evaluating the use of the synthetic media as a substitute to swine wastewater in experiments where its use in not viable. The results showed that the synthetic media presented a similar behavior to the control. The reactors reached the steady state after approximately 40-45 days of operation. For both medias, the larger the organic loading rate applied, the smaller the efficiency of COD removal reached. The similarity in the behavior, in relation to the removal of organic matter and the stability of the system, justifies the use of the synthetic media as a model for the evaluation of swine wastewater treatment systems

Metabolism of biodiesel-derived glycerol in probiotic Lactobacillus strains

Three probiotic Lactobacillus strains, Lactobacillus acidophilus, Lactobacillus plantarum, and Lactobacillus delbrueckii, were tested for their ability to assimilate and metabolize glycerol. Biodiesel-derived glycerol was used as the main carbon and energy source in batch microaerobic growth. Here, we show that the tested strains were able to assimilate glycerol, consuming between 38 and 48 % in approximately 24 h. L. acidophilus and L. delbrueckii showed a similar growth, higher than L. plantarum. The highest biomass reached was 2.11 g L−1 for L. acidophilus, with a cell mass yield (Y X/S) of 0.37 g g−1. L. delbrueckii and L. plantarum reached a biomass of 2.06 and 1.36 g L−1. All strains catabolize glycerol mainly through glycerol kinase (EC 2.7.1.30). For these lactobacillus species, kinetic parameters for glycerol kinase showed Michaelis–Menten constant (K m) ranging from 1.2 to 3.8 mM. The specific activities for glycerol kinase in these strains were in the range of 0.18 to 0.58 U mg protein−1, with L. acidophilus ATCC 4356 showing the maximum specific activity after 24 h of cultivation. Glycerol dehydrogenase activity was also detected in all strains studied but only for the reduction of glyceraldehyde with NADPH (K m for DL-glyceraldehyde ranging from 12.8 to 32.3 mM). This enzyme shows a very low oxidative activity with glycerol and NADP+ and, most likely, under physiological conditions, the oxidative reaction does not occur, supporting the assumption that the main metabolic flux concerning glycerol metabolism is through the glycerol kinase pathway