Herbaspirillum seropedicae as a degrading bacterium of monofluoroacetate: effects of its inoculation in goats by ingesting Amorimia septentrionalis and the concentrations of this compound in plants sprayed with the bacterium / Herbaspirillum seropedicae como bactéria degradadora de monofluoroacetato de sódio: efeitos de sua inoculação em caprinos ingerindo Amorimia septentrionalis e nas concentrações deste composto em plantas pulverizadas com a bactéria

Herbaspirillum seropedicae is a nitrogen-fixing bacterium capable of using toxic compounds as a source of carbon. Bacteria with this capacity can be used to make animals resistant to plant poisoning containing monofluoroacetate (MFA), such as Amorimia septentrionalis. The aim of this study was to evaluate if H. seropedicae is efficient in the degradation of MFA present in A. septentrionalis and if the inoculation of this bacterium in goats confers protection to A. septentrionalis intoxication. Two experiments were performed: in the first experiment 12 goats were divided into 2 groups. Goats in Group 1 were orally administered a solution containing the H. seropedicae bacterium for 10 days. From day 10 onwards, they received a daily dose of 5g/kg of A. septentrionalis with the bacteriauntil clinical signs of intoxication were observed. Group 2 goats received only the plant at the same dose, also until the observation of clinical signs of intoxication. The amount of MFA found in A. septentrionalis used in the experiment with goats was 1.6±0.058μg/mg. The total plant dose ingested by all goats in Group 1 was 80.83±12.81g/kg (129.33±20.50mg/kg MFA), which were significantly greater ​​(p<0.05) than those of Group 2 goats (39.16±19.08g/kg plant and 62.66±30.53mg/kg MFA). Group 1 goats took an average of 16.16±2.56 days to develop clinical signs of intoxication, significantly longer (p=0.0012) than Group 2 goats (7.83±3.81 days). Two Group 2 goats died on the same day that they developed clinical signs of intoxication. At necropsy of these two animals, no significant changes were observed. In the second experiment, samples of A. septentrionalis were sprayed with a solution containing H. seropedicae. Before and eight days after spraying, the samples were pressed and dried for quantitation of MFA. The amount of MFA present in samples of A. septentrionalis 8 days after spraying with H. seropedicae was significantly lower (p=0.017) than that found prior to spraying. It can be concluded that administration of H. seropedicae in goats is capable of causing greater resistance to A. septentrionalis intoxication, and spraying the plant with this bacterium significantly reduces the amount of MFA in the plant.(AU)

Herbaspirillum seropedicae é uma bactéria fixadora de nitrogênio, capaz de utilizar compostos tóxicos como fonte de carbono. Bactérias com essa capacidade podem ser utilizadas para tornar os animais resistentes à intoxicação por plantas que contém monofluoroacetato (MFA), como Amorimia septentrionalis. O objetivo do presente estudo é avaliar se H. seropedicae é eficiente na degradação do MFA presente em A. septentrionalis e se a inoculação dessa bactéria, em caprinos, confere proteção à intoxicação por A. septentrionalis. Foram realizados dois experimentos: no primeiro experimento foram utilizados 12 caprinos, divididos em dois grupos. Os caprinos do Grupo 1 receberam diariamente, oralmente, uma solução contendo a bactéria H. seropedicae durante 10 dias. A partir do décimo dia passaram a receber, diariamente, além da solução com a bactéria 5g/kg de A. septentrionalis até a observação de sinal clínico de intoxicação. Os caprinos do Grupo 2 receberam apenas a planta na mesma dose, também até que a observação de sinais clínicos de intoxicação. A quantidade de MFA encontrada em A. septentrionalis utilizada no experimento com caprinos foi de 1,6± 0,058µg/mg de planta em média. A dose total de planta ingerida por todos os caprinos do Grupo 1 foi de 80,83±12,81g/kg (129,33±20,50mg/kg de MFA), valores significativamente maiores (p<0,05) do que os dos caprinos do Grupo 2 (39,16±19,08g/kg de planta e 62,66± 30,53mg/Kg de MFA). Os caprinos do Grupo 1 demoraram em média 16,16 ±2,56 dias para desenvolver sinais clínicos da intoxicação, período significativamente maior (p=0,0012) que os caprinos do Grupo 2 (7,83±3,81dias). Dois caprinos do Grupo 2 morreram no mesmo dia que desenvolveram sinais clínicos da intoxicação. Na necropsia desses dois animais não foram observadas alterações significativas. No segundo experimento, amostras de A. septentrionalis foram pulverizadas com uma solução contendo a bactéria H. seropedicae. Antes e oito dias após a pulverização, as amostras foram prensadas e secas para posterior quantificação do MFA. A quantidade de MFA presente nas amostras de A. septentrionalis oito dias após a pulverização com H. seropedicae foi significativamente menor (p=0,017) do que a encontrada antes da pulverização. Pode-se concluir que a administração de H. seropedicae em caprinos é capaz de causar uma maior resistência à intoxicação por A. septentrionalis, e a pulverização da planta com esta bactéria reduz significativamente a quantidade de MFA na planta.(AU)

Screening and enzymatic study of a composite microbial system FH3

Five strains of fungi and 18 strains of bacteria were isolated from the soil and horse manure with cellulose as the sole carbon source. Among them, two fungal, F9 and F13, and two bacterial, B16 and B21, showed the highest filter paper activities, which were 7.79 U g-1, 9.84 U g-1, 7.34 U g-1 and 9.68 U g-1, respectively. Four microbial systems, designed as FH1 (F13+B21), FH2 (F13+B16+B21), FH3 (F9+B16+B21) and FH4 (F13+F9+B16+B21) were developed. The fermentation studies showed that the filter paper activity of the composite microbial system FH3 was higher than the others, which was 21.34 U g-1. The medium with bran and filter paper as the carbon source and peptone as nitrogen source was optimal and the maximum cellulase activity was reached at 30~35ºC and pH 6.0~6.5 when FH3 was incubated for 48 h. The enzymatic reaction conditions were estimated at 45~55 ºC, pH 4.5~5.5 and the thermal stability temperature was up to 60 ºC.

Characters and Oil Field Trial of Oil-Degrading Bacterium Strain NX-2 / 微生物学通报

Based on reservoir condition and fluid characteristics, the oil-degrading bacterial strain NX-2 was screened from Ma-2 fault block of Huabei oil field. Bacterial metabolism and the capability of improving oil property were evaluated on oxygen-deficient condition. At 87℃ which reservoir temperature is, artificial homogeneous core displacement experiment indicated the enhanced oil recovery of microbe was 7.1% higher than that of waterflooding. In experiment on individual well Ma-410, additional oil production of 669 tons was gained, and decreased water production of this trial well reached more than 3000 tons. These results demonstrated NX-2 could adapt to stratum conditions, enhance oil recovery and improve oil property as well.

STUDIES ON TREATMENT OF ODL FIELD WASTEWATER BY OIL-DEGRADING BACTERIA / 微生物学通报

A mixed bacteria culture F6 isolated from oil field wastewater can degrade petroleum hydrocarbons efficiently. The bacteria were suitable to treat oil-polluted wastewater of oil field. Simulated result treating oil-polluted wastewater in laboratory showed that after "XingyiLian" wastewater of Liaohe Oil Field was treated by fluidized-bed bioreactor system with the vehicle of activated carbon , the amount of oil and CODcr of the flow out water were decreased from 45mg/L to 4. 1mg/L and 470mg/L to 42mg/L separately , according with first class standards of Chinese Wastewater Discharge Regulation.