Production and characterization of surface-active compounds from Gordonia amicalis

Two methods were used to make crude preparations of surface-active compounds (SACs) produced by Gordonia amicalis grown on the medium containing 1% diesel oil. Using a 2:1 (v/v) solution of chloroform:methanol for extraction, Type I SACs were isolated and shown to produce oil in water (O/W) emulsions. Type II SACs were isolated by precipitation with ammonium sulfate and produced predominantly water in oil emulsions (W/O). The crude Type I and II preparations were able to produce a significant reduction in the surface tension of water; however, the crude Type II preparation had 10-25 fold higher emulsification activity than the Type I preparation. Both SAC preparations were analyzed by the TLC and each produced two distinct bands with Rf 0.44 and 0.62 and Rf 0.52 and 0.62, respectively. The partially purified SACs were characterized by the ESI(+)-MS, FT-IR and NMR. In each one of these fractions, a mixture of 10 oligomers was found consisting of a series of compounds, with masses from 502 to 899, differing in molecular mass by a repeating unit of 44 Daltons. The mass spectra of these compounds did not appear to match other known biosurfactants and could represent a novel class of these compounds.

Obtainment and characterization of mannoproteins from brewers yeast cell wall - doi: 10.4025/actascibiolsci.v34i1.7124 / Obtenção e caracterização de manoproteínas da parede celular de leveduras de descarte em cervejaria - doi: 10.4025/actascibiolsci.v34i1.7124

The biomass of yeast after beer production is a raw-material for cell components extraction, including mannoproteins. The present study evaluated the using viability of spent brewers yeast Saccharomyces sp. for obtainment of extract containing mannoprotein. The extraction was conducted by Box-Behnken 33 incomplete design, for the variables temperature (75, 85 and 95ºC), time of extraction (5, 7 and 9h) and concentration of cell wall in suspension (10, 15 and 20%). The residual ethanol of fermentation doesnt have interference in the obtaining of extract containing mannoproteins. The highest rate of extraction was 4.08%, obtained at 95ºC, with 10% cell wall by 7h and with 15% of cell wall during 9h. The experimental validation for obtaining of the maximum predicted resulted in 4.50% of extract, confirming the model predictable capacity. The extract containing mannoprotein obtained from 10% of cell wall (95ºC, 9h) had 51.39% of proteins, with 58 and 64 kDa, and 25.89% of carbohydrates, distributed in mannose and glucose. The emulsification activity was 62.50 ± 0.88% and the emulsion stability was 96.00 ± 1.4%. These results evidence the bioemulsifier potential of the extract and the viability of using spent yeast from brewery for obtainment of compounds with industrial interesting properties.

A biomass de levedura resultante da produção de cerveja é mátéria-prima para extração de componentes celulares, incluíndo manoproteínas. O presente trabalho avaliou a possibilidade da utilização da levedura Saccharomyces sp. descartada em cervejaria, para obtenção de extrato com manoproteínas. A extração foi conduzida segundo delineamento fatorial incompleto, Box-Behnken 33, para as variáveis temperaturas (75, 85 e 95ºC), tempo de extração (5, 7 e 9h) e concentração da suspensão de parede celular (10, 15 e 20%). O etanol residual da fermentação não interfere na obtenção do extrato contendo manoproteínas. O maior índice de extração foi 4,08%, observado para temperatura de 95ºC na concentração de 10% por 7h e 15% por 9h. A validação experimental do maior índice predito resultou em 4,50% de extrato, confirmando a capacidade preditiva do modelo. A manoproteína obtida, a partir de 10% de parede celular (95ºC, 9h), apresentou 51,39% de proteínas, com 58 e 64 kDa, e 25,89% de carboidratos, distribuídos entre manose e glicose. A atividade emulsificante foi de 62,50 ± 0,88% e a estabilidade da emulsão foi de 96,00 ± 1,40%. Estes resultados evidenciam o potencial bioemulsificante do extrato e a viabilidade de utilização da levedura descartada em cervejarias para obtenção de compostos com propriedades industriais interessantes

Obtenção e caracterização de manoproteínas da parede celular de leveduras de descarte em cervejaria / Obtainment and characterization of mannoproteins from brewer's yeast cell wall

A biomassa de levedura resultante da produção de cerveja é mátéria-prima para extração de componentes celulares, incluíndo manoproteínas. O presente trabalho avaliou a possibilidade da utilização da levedura Saccharomyces sp. descartada em cervejaria, para obtenção de extrato com manoproteínas. A extração foi conduzida segundo delineamento fatorial incompleto, Box-Behnken 33, para as variáveis temperaturas (75, 85 e 95ºC), tempo de extração (5, 7 e 9h) e concentração da suspensão de parede celular (10, 15 e 20%). O etanol residual da fermentação não interfere na obtenção do extrato contendo manoproteínas. O maior índice de extração foi 4,08%, observado para temperatura de 95ºC na concentração de 10% por 7h e 15% por 9h. A validação experimental do maior índice predito resultou em 4,50% de extrato, confirmando a capacidade preditiva do modelo. A manoproteína obtida, a partir de 10% de parede celular (95ºC, 9h), apresentou 51,39% de proteínas, com 58 e 64 kDa, e 25,89% de carboidratos, distribuídos entre manose e glicose. A atividade emulsificante foi de 62,50 ± 0,88% e a estabilidade da emulsão foi de 96,00 ± 1,40%. Estes resultados evidenciam o potencial bioemulsificante do extrato e a viabilidade de utilização da levedura descartada em cervejarias para obtenção de compostos com propriedades industriais interessantes.

The biomass of yeast after beer production is a raw-material for cell components extraction, including mannoproteins. The present study evaluated the using viability of spent brewer's yeast Saccharomyces sp. for obtainment of extract containing mannoprotein. The extraction was conducted by Box-Behnken 33 incomplete design, for the variables temperature (75, 85 and 95ºC), time of extraction (5, 7 and 9h) and concentration of cell wall in suspension (10, 15 and 20%). The residual ethanol of fermentation doesn't have interference in the obtaining of extract containing mannoproteins. The highest rate of extraction was 4.08%, obtained at 95ºC, with 10% cell wall by 7h and with 15% of cell wall during 9h. The experimental validation for obtaining of the maximum predicted resulted in 4.50% of extract, confirming the model predictable capacity. The extract containing mannoprotein obtained from 10% of cell wall (95ºC, 9h) had 51.39% of proteins, with 58 and 64 kDa, and 25.89% of carbohydrates, distributed in mannose and glucose. The emulsification activity was 62.50 ± 0.88% and the emulsion stability was 96.00 ± 1.4%. These results evidence the bioemulsifier potential of the extract and the viability of using spent yeast from brewery for obtainment of compounds with industrial interesting properties.

Bioemulsifier production by Streptomyces sp. S22 isolated from garden soil.

Out of 45 actinomycetes isolated from garden soil, pond water and air; fifteen showed good emulsification activity. Streptomyces sp. S22 isolated from garden soil produced maximum bioemulsifier with 0.5% (v/v) sunflower oil during stationary phase at 37°C, pH 6 and 250 rev/min. Emulsification activity was maximum (320 EU/ml) with sunflower oil as substrate. Partially purified bioemulsifier from Streptomyces sp. S22 was a peptidoglycolipid containing lipid (51.25%), protein (30%), non-reducing sugar (17.75%) and reducing sugar (1%). The yield of partially purified bioemulsifier was 1.6 g/l and reduced the surface tension of water by 23.09 mN/m. The bioemulsifier produced by Streptomyces sp. S22 was stable at room temperature for seven days.

Production of bioemulsifier by Acinetobacter species isolated from healthy human skin.

Six Acinetobacter sp. isolated from healthy human skin were checked for the production of bioemulsifier. Optimization studies indicated that Luria Bertani broth pH 7 supplemented with calcium chloride (1%) was the optimum medium. Temperature at 37°C was optimum and inducer oils in the medium did not enhance bioemulsifier production. Partial purification of bioemulsifier and chemical analysis revealed that it is a proteoglycan with protein (53%), polysaccharide (43%) and lipid (2%). Maximum emulsification activity obtained was 400 EU/ml. Thin layer chromatography revealed the presence of mannose and rhamnose sugar and oleic and palmitic acids as parts of lipids. The yield obtained was 1.9 g / l. Reconstitution studies revealed that the protein and polysaccharide fractions together display 94.55% of emulsification activity. It was also noted that the bioemulsifier was stable for 72 hr at 37°C and displayed good cleaning property towards different oils. The partially purified bioemulsifier formed stable oil-in-water emulsions with plant oils.

Study on the Bioemulsifier Produced by a Hydrocarbon- degrading Strain T7-2 and Its Physic-chemical Properties / 微生物学通报

A low-temperature hydrocarbon-degrading strain T7-2, isolated from sea-mud of Bohai polluted area and identified as Rhodococcus erythropolis, was found to produce an extracellular, nondialyzable emul- sifying agent (referred to as bioemulsifier) when grew with hexadecane as carbon source. The results showed that, this bioemulsifier which could remarkably emulsify hydrocarbons such as diesel oil, is consisted of three parts-carbohydrates, lipids and proteins, the proportion of which was 55.43:31.24:12.65. The mono- saccharide compositions were identified as mannose and rhamnose; the lipid compositions included de- canoic acid, lauric acid, hexadecanoic acid and stearic acid, and the protein constituents were composed of sixteen amino acids. Besides, according to the study of the physic-chemical properties of the bioemulsifier, it possesses the obvious advantages of character stability, high function efficiency and wide adaptation range, therefore this bioemulsifier is believed to have extensive application values for bioremediation of marine oil pollution, petroleum exploitation and etc.