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1.
Article | IMSEAR | ID: sea-230321

RÉSUMÉ

Soil microbiological properties viz. soil microbial biomass carbon (MBC) and dehydrogenase activity (DHA) are sensitive soil quality indicators. Spatial modeling and prediction map of soil MBC and DHA were generated for a semiarid agricultural farm, New Delhi, India from 288 geo-referenced grid samples spaced 100 m × 100 m distance using geospatial techniques and geo-statistics. Soil microbial biomass carbon (MBC) ranged from 19.7 to 519.7 µg g-1 with standard deviation of 84.1 and soil DHA varied from 1.2 to 17.2 µg TPF g-1 dry soil hr-1 with sample variance of 10.89. Soil MBC and DHA had high data viability with coefficient of variation (CV) of 42.5 % and 53.2%, respectively. The best fit semivariogram for both soil MBC and DHA was exponential model and had practical spatial range of 1500 m and 1473 m respectively. Environmental disturbances or extrinsic factors dominantly influenced the spatial variability of soil MBC, expressing its weak spatial dependency. Besides, both soil structural/internal factors and extrinsic factors controlled soil DHA variability with moderate level of spatial dependency. Spatial variability map of soil MBC and DHA, prepared with good accuracy through ordinary kriging in GIS software, showed that major area of the farm had soil MBC ranging from 150 to 250 mg kg-1 and had DHA from 1.2 to 10 µg TPF g-1 dry soil hr-1.

2.
Article | IMSEAR | ID: sea-228974

RÉSUMÉ

A field experiment was conducted to study the effect of different organic manures and their levels on nutrient status and soil microbial activity in rose at Hisar during 2020-21. The treatments comprised of 3 different types of organic manures viz., farm yard manures, vermicompost and poultry manure and 4 levels control, 4 kg/m2, 5 kg/m2 and 6 kg/m2. The experiment was carried out in the split plot design with three replications. Observation on organic carbon, dehydrogenase activity and alkaline phosphatase activity, N, P and K content in rose leaves and available N, P and K content in soil at the time of harvest were recorded. Organic carbon in soil was maximum (0.93%) with the application of vermicompost while dehydrogenase and alkaline phosphatase activity were highest with the application of farmyard manure and poultry manure, respectively. Nitrogen (2.17%) and phosphorus (0.27%) content were maximum in rose leaves at harvest stage with the application of poultry manure while Potassium (1.41%) content was maximum vermicompost. Same trend was observed in the nutrient status of soil with the application of different organic manures. It is concluded that the application of poultry manures had pronounced effect on microbial activity and nutrient status in rose.

3.
Braz. j. microbiol ; Braz. j. microbiol;47(3): 741-748, July-Sept. 2016. tab, graf
Article de Anglais | LILACS | ID: lil-788949

RÉSUMÉ

ABSTRACT Aminotransferases and glutamate dehydrogenase are two main types of enzymes involved in the initial steps of amino acid catabolism, which plays a key role in the cheese flavor development. In the present work, glutamate dehydrogenase and aminotransferase activities were screened in twenty one strains of lactic acid bacteria of dairy interest, either cheese-isolated or commercial starters, including fifteen mesophilic lactobacilli, four thermophilic lactobacilli, and two streptococci. The strains of Streptococcus thermophilus showed the highest glutamate dehydrogenase activity, which was significantly elevated compared with the lactobacilli. Aspartate aminotransferase prevailed in most strains tested, while the levels and specificity of other aminotransferases were highly strain- and species-dependent. The knowledge of enzymatic profiles of these starter and cheese-isolated cultures is helpful in proposing appropriate combinations of strains for improved or increased cheese flavor.


Sujet(s)
Humains , Streptococcus/enzymologie , Glutamate dehydrogenase/métabolisme , Transaminases/métabolisme , Lactobacillus/enzymologie , Système acellulaire , Activation enzymatique , Microbiologie alimentaire
4.
Rev. argent. microbiol ; Rev. argent. microbiol;47(3): 212-218, set. 2015. ilus, tab
Article de Anglais | LILACS | ID: biblio-843128

RÉSUMÉ

In this microcosm study, we analyzed the effect produced by hydroquinone on the expression of soil biological denitrification, in relation to the redox state of the soil, both in terms of intensity factor (Eh′) and capacity factor (amount of oxidized or reduced compounds). The supplementation of an Argiudoll soil with hydroquinone decreased the soil apparent reduction potential (Eh′) and soil dehydrogenase activity (formazan production from tetrazolium chloride reduction; redox capacity factor), the relationship between both factors being highly significative, r = 0.99 (p < 0.001). The bacterial population (measured by colony forming units) increased, and the production of N2O was greater (p < 0.001) at 200 and 400 μg/g dry soil doses. Furthermore, there was an inverse relationship between soil dehydrogenase activity and the number of bacteria (r = −0.82; p < 0.05), increased denitrification activity and changes in the CO2/N2O ratio value. These results suggest that hydroquinone at supplemented doses modified the soil redox state and the functional structure of the microbial population. Acetate supplementation on soil with hydroquinone, to ensure the availability of an energy source for microbial development, confirmed the tendency of the results obtained with the supplementation of hydroquinone alone. The differences observed at increased doses of hydroquinone might be explained by differences on the hydroquinone redox species between treatments.


En este trabajo estudiamos, en condiciones de microcosmos, el efecto que produce la hidroquinona sobre la expresión de la desnitrificación en relación con el estado de óxido-reducción del suelo, en términos de factor de intensidad (Eh′) y de factor de capacidad (cantidad de compuestos oxidados o reducidos). La suplementación de un suelo argiudol con hidroquinona disminuyó el potencial de reducción aparente (Eh′) y la actividad deshidrogenasa (producción de formazán a partir de la reducción de cloruro de tetrazolio; factor de capacidad redox), la relación entre ambos factores fue altamente significativa, r = 0,99 (p < 0,001). La población bacteriana heterotrófica (medida como unidades formadoras de colonias) aumentó y la producción de N2O fue mayor (p < 0,001) con las dosis de 200 y 400 μg/g de suelo seco. Además se observó una relación inversa entre la producción de formazán y el número de bacterias (r = −0,82; p < 0,05), la actividad desnitrificadora aumentó y se produjeron cambios en el valor del cociente CO2/N2O. Estos resultados sugieren que la hidroquinona, en las dosis empleadas, modificó el estado redox del suelo y la estructura funcional de la población microbiana. La suplementación con acetato en el suelo con hidroquinona, a fin de asegurar la disponibilidad de una fuente de energía para el desarrollo bacteriano, confirmó la tendencia de los resultados obtenidos con la suplementación con hidroquinona solamente. Las diferencias observadas con el incremento en la dosis de hidroquinona podrían explicarse por las diferencias sobre las especies redox de la hidroquinona entre los tratamientos.


Sujet(s)
Biologie du Sol/analyse , Zones Agricoles/prévention et contrôle , Dénitrification/effets des médicaments et des substances chimiques , Hydroquinones/administration et posologie , Oxydoréduction/effets des médicaments et des substances chimiques , Caractéristiques du Sol/analyse , Traitement du Sol , Interactions microbiennes/physiologie
5.
Int. j. morphol ; 29(2): 412-419, June 2011. ilus
Article de Anglais | LILACS | ID: lil-597467

RÉSUMÉ

The effects of sublethal concentrations of cadmium (0.64 µg/L), iron (0.043 mg/L) and zinc (0.31 mg/L) and a mixture of these metals on succinate dehydrogenase (SD) and alkaline phosphatase (AP) activity and on structural changes in the mitochondria of epithelium cells of the digestive tract were examined in the oligochaete Limnodrillus hoffmeisteri after 96 h of exposure in artificial sediments. SD activity was significantly inhibited, particularly in treatments with Cd alone (92.57 percent), while AP increased its activity with Cd alone (73.23 percent). However, when this metal was mixed with Fe and Zn, the inhibition of SD activity was lower (67.82 percent) than with Cd alone, showing an antagonistic effect and AP increased its activity (73.26 percent). Mitochondria were structurally damaged by exposure to Cd alone. However, in the metal mixtures, the toxic effects may exert interactive effects eliciting a less structural damage in the mitochondria of epithelium cells of the digestive tract than when Cd is alone.


Se estudió el efecto de las concentraciones subletales de Cd (0,64 µg/L), Fe (0,043 mg/L) y Zn (0,31 mg/L) en forma aislada y en mezcla sobre la actividad de la succinato deshidrogenasa (SD) y la fosfatasa alcalina (AP) en las mitocondrias de las células epiteliales del tracto digestivo en el oligoqueto Limnodrillus hoffmeisteri después de 96 h de exposición en sedimentos artificiales. La SD se inhibió significativamente, particularmente en los tratamientos con Cd en forma aislada (92,57 por ciento), mientras que la AP se incrementó con Cd en forma aislada (73,23 por ciento). Sin embargo, cuando este metal se mezcló con Fe y Zn, la inhibición de la SD fue menor (67,82 por ciento) que con Cd en forma aislada, lo que mostró un efecto antagonístico y la AP incrementó su actividad (73,23 por ciento). Sin embargo, cuando este metal estaba en mezcla con Fe y Zn, la inhibición de la SD fue menor (67,82 por ciento) que con Cd en forma aislada, mostrando un efecto antagonístico y un incremento en la actividad de la AP (73,26 por ciento). Las mitocondrias fueron dañadas estructuralmente por exposición al Cd en forma aislada. Sin embargo, con los metales en mezcla, los efectos tóxicos pudieron ejercer efectos interactivos provocando un menor daño estructural en la mitocondria de las células del epitelio del tracto digestivo que cuando el Cd estaba en forma aislada.


Sujet(s)
Animaux , Oligochaeta , Succinate Dehydrogenase/effets des médicaments et des substances chimiques , Zinc/toxicité , Cadmium/toxicité , Phosphatase alcaline/effets des médicaments et des substances chimiques , Fer/toxicité , Métaux lourds/toxicité , Cellules épithéliales/effets des médicaments et des substances chimiques , Mitochondries
6.
Braz. j. microbiol ; Braz. j. microbiol;42(2): 531-542, Apr.-June 2011. tab
Article de Anglais | LILACS | ID: lil-590000

RÉSUMÉ

The field experiments were conducted on sandy loam soil at New Delhi, during 2007 and 2008 to investigate the effect of conservation tillage, irrigation regimes (sub-optimal, optimal and supra-optimal water regimes), and integrated nutrient management (INM) practices on soil biological parameters in wheat cultivation. The conservation tillage soils has shown significant (p<0.05) increase in soil respiration (81.1 percent), soil microbial biomass carbon (SMBC) (104 percent) and soil dehydrogenase (DH) (59.2 percent) compared to the conventional tillage soil. Optimum water supply (3-irrigations) enhanced soil respiration over sub-optimum and supra-optimum irrigations by 13.32 percent and 79 percent respectively. Soil dehydrogenase (DH) activity in optimum water regime has also increased by 23.33 percent and 8.18 percent respectively over the other two irrigation regimes. Similarly, SMBC has also increased by 12.14 percent and 27.17 percent respectively in soil with optimum water supply compared to that of sub-optimum and supra-optimum water regime fields. The maximum increase in soil microbial activities is found when sole organic source (50 percent Farm Yard Manure+25 percent biofertilizer+25 percent Green Manure) has been used in combination with the conservation tillage and the optimum water supply. Study demonstrated that microbial activity could be regulated by tillage, water and nitrogen management in the soil in a sustainable manner.

7.
Rev. argent. microbiol ; Rev. argent. microbiol;40(2): 120-123, abr.-jun. 2008. tab
Article de Anglais | LILACS | ID: lil-634590

RÉSUMÉ

The incorporation of biosolids to soil is a strategy aiming at the re-location of these materials in the environment with a useful end: soil fertilization. In this work, the response of two Argiudoll soils (one with more than 100 years of agriculture and the other, a virgin one) to biosolid incorporation was studied under laboratory conditions. To measure this response, soil enzymatic biodescriptors, such as dehydrogenase and urease activities, and tests related to plant physiology (the root elongation test) were employed. The addition of the biosolid to both soils had a stimulating effect though different on each soil according to the added dose. Adjustment of the regression line for dehydrogenase activity with root elongation was positive and statistically significant (p<0.001). Results suggest that biodescriptors employed were suitable for studying the impact of amended biosolids on different soils.


La incorporación de biosólidos al suelo es una estrategia que tiene como objetivo la reubicación de estos materiales en el ambiente con un fin útil, como es la fertilización del suelo. En este trabajo se estudió, en condiciones controladas de laboratorio, la respuesta de dos suelos Argiudoles (uno con más de 100 años de agricultura y otro virgen) frente a la perturbación físico-química y biótica que genera la incorporación de un biosólido. Para medir esta respuesta se emplearon dos biodescriptores edáficos (las actividades deshidrogenasa y ureasa) y un tercero referido a la fisiología vegetal, la prueba de elongación de raíces. La incorporación del biosólido en ambos suelos, en general no deprimió el funcionamiento de las actividades enzimáticas estudiadas; contrariamente, según la dosis aportada tuvo un efecto estimulante, aunque diferente, entre ambos suelos. El ajuste de la recta de regresión de la actividad deshidrogenasa con la elongación de las plántulas fue positivo y altamente significativo, lo que indica la complementaridad de ambos descriptores. Los resultados obtenidos sugieren que los biodescriptores empleados resultaron aptos para estudiar el impacto que produce la incorporación de biosólidos a suelos agrícolas.


Sujet(s)
Oxidoreductases/métabolisme , Racines de plante/enzymologie , Racines de plante/croissance et développement , Eaux d'égout , Sol , Urease/métabolisme , Argentine
8.
Article de Anglais | IMSEAR | ID: sea-138239

RÉSUMÉ

The ability of the human normal uterine cervix and cervical carcinoma to interconvert estradiol-17β and estrone is due to the activity of 17β-hydroxysteroid dehydrogenase (17β-HSD). Human cervical 800 x g supernatant fractions were analyzed by incubating with 3H-estradiol (20 nM) and NAD (0.25 ตmol) in 50 mM Tris buffer at pH 8.0. The incubation was terminated by adding 1 ml of 100% methanol and the supernatants were evaporated in air. The dry residues were resuspended in methanol, and aliquots were chromatographed in silica gel thin layer plates in benzene : ethanol (9 : 1, V : V). The 17β-HSD activity was determined from the amount of estrone formed and expressed as nanomoles of estrone formed/mg protein X h. The 17β-HSD activity was higher in normal cervix than in cervical carcinoma. Estradiol-17β added to incabation mixture caused a slight increase in enzyme activity only in cervical carcinoma while it had no effect in normal tissues. Progesterone administration increased 17β-HSD activity in some cases of normal and carcinoma cervix. These results suggest that changes in enzyme concentrations may play a physiologic role in the regulation of tissue levels of estradiol-17β.

9.
Article de Coréen | WPRIM | ID: wpr-34905

RÉSUMÉ

This sutdy was performed to find out a LD isoenzyme pattern in neoplastic tissue of gastric carcinoma and in gastric mucosa with intestinal metaplasia, which has been known as premalignant lesion. The specimens used in this study were 18 stomachs with caarcinoma and 8 stomachs with peptic ulcer as control, and wer obtained by subtotal or total gastrectomy at Pusan National University Hsopital from Oct. 1987 to Sept. 1988. Total LD activity and its isoenzymes in body and antral mucosae and neoplastic tissue of stomach were assayed, and analysed statistically from several points of view. The results obtained were summarized as follows: 1) There was no significant difference in total LD activity between univolved body and antral mucosae of stomach with carcinoma, and between mucosa of stomach with peptic ulcer and univolved mucosa of stomach with carcinoma. 2) Total LD activity in the neoplastic tissue of gastric carcinoma was significantly higher than those of univolved body and antral mucosae of stomach with carcinoam or that of stomach with peptic ulcer, but no significant difference was observed among histological types of gastric carcinoma. 3) The uninvolved body mucosa of stomach with carcinoma or peptic ulcer showed a pattern of LD1 predominance and increas of H to M ratio, while the antral mucosa of stomach with carcinoma or peptic ulcer showed a pattern of LD3 predominance and decrease of H to M ratio. 4) The LD4 and LD5 fractions in antral mucosa with moderate to severe intestinal metaplasia were slightly increased than those of antral mucosa with nil to mild intestinal metaplasia, but did not show statistically significant difference. 5) Marked increase of LD5 fraction was found in neoplastic tissue of gastric carcinoma, and thus ratio of H to M subunit in neoplastic tissue was significantly lower, as compared with body or antral univolved mucosa of stomach. In conclusion, the neoplastic tissue of gastric carcinoma and gastric mucosa with intestinal metaplasia show substantially predominant "M" subunit as well as increased total LD activity.

10.
Article de Chinois | WPRIM | ID: wpr-553858

RÉSUMÉ

AIM To observe the effects of melatonin on acute and chronic injuries induced by oxygen and glucose deprivation (OGD) in co-cultured neuron and glia and to explore the probable mechanisms of melatonin in antagonizing the injuries. METHODS The injury model of cultured neuron and co-cultured neuron and glia was made by administration of sodium dithionite and glucose-deprived Earles solution. In neuron and glia co-culture, two different models, acute injury model at the phase of OGD and chronic injury model after 'reperfusion' were established. The levels of nitric oxide (NO) and the activity of lactate dehydrogenase (LDH) were measured by Griess reagent and LDH kits respectively. The content of malondialdehyde (MDA) was determined by TBA method. Cell viability was analyzed using colorimetric MTT assay. RESULTS Melatonin increased the level of NO at the concentration of 10 -6 , 10 -7 mol?L -1 and decreased the level of MDA content elevated by OGD at the concentration of 10 -6 , 10 -7 , 10 -8 mol?L -1 in vitro cultured cortical neurons. In the chronic injury model after 'reperfusion' melatonin (10 -6 , 10 -7 , 10 -8 mol?L -1 ) significantly decreased LDH activity and increased MTT value in neurons and glia co-cultured. But in the acute injury model, melatonin obviously increased LDH activity and decreased MTT value. CONCLUSION Melatonin protection for neuron from injuries induced by oxygen and glucose deprivation may be related to increase in the level of NO and decrease in the content of MDA. Melatonin can antagonize the injury in the chronic injury model after 'reperfusion', but exaggerate the injury in the acute injury model. These may be all related to its antioxidant action. Our results also suggest that melatonin may probably inhibit activation of microglia.

11.
Article de Coréen | WPRIM | ID: wpr-105585

RÉSUMÉ

As a process to study the mechanism of steroid hormones at the molecular level,the activities of lactic dehydrogenase (L.D.) and malic dehydrogenase (M.D.),NAD-linked transhydrogenases, were measured in the testis and the prostate. Ahundred male rabbits were divided into ten group as follows: Group 1: Control Group 2: Estrogen (6,000 units) injected Group 3: Androgen (1,200 unite)injected Group 4: Progesterone (1,200 units) injected Group 5: Hydrocortisone(30 mg) injected Group 6: DOCA (6 mg) injected Group 7: Castration control Group8: Castration and estrogen (6, OOO units) injected Group 9: Castration and androgen (1,200 units) injected Group 10: Castration and progesterone (1,200units) injected Changes in the activities of lactic dehydrogenase and malic dehydrogenase in theorganic tissues by exogenous steroid hormones were carefullyobserved. The lactic dehydrogenase activities were measured by the method of Wroblewski and La Due, and malic dehydrogenase activities by the Bodansky's modification of Porter's method. The results are as follows: 1) The control valueof L.D. activities in the testicular tissue of normal rabbits proved to be 89,400units per ram. The L.D. activities showed an increase up to 110.4 per cent in theestrogen injected group, 179.3 per cent in the androgen injected group and 147.0 per cent in the progesterone injected group, while the administration of hydrocortisone and DOCA decreased the value down to 85.2 per cent and 81.5 per cent, respectively. 2) The control value of M.D. activities in the testicular tissue of the normal rabbits was 23,600 units per gram. The M.D. activities showed an increase upto 111.4 per cent in the estrogen injected group. 191.1 per cent in the androgen injected group, and 156.8 per cent in the progesterone injected group, while the administration of hydrocortisone and DOCA decreased the value down to 85.2 per cent and 81.5 per cent, respectively. 3) In the prostate tissues of non-castrated rabbits, the L.D. activities were estimated normally to be 48,100 units per gram. The administration of sex hormone resulted in raising the activities upto 101.8 per cent in the estrogen injected group, 196.9 per cent in the androgen injected group and 153.9 per cent in the progesterone injected group. But the administration of hydrocortisone and DOCA decreased the value down to 92.5 per cent and 97.1 per cent, respectively. 4) In the prostate tissue of non-castrated rabbits, the control value of M.D. activities proved to be 14,600 unite per gram. The M.D. activities showed an increase upto 117.8 per cent in the estrogen injected group, 206.8 per cent in the androgen injected group and, 176.7 per cent in the progesterone injected group, while the administration of hydrocortisone and DOCA decreased the value down to 81.9 per cent and 95.2 per cent, respectively. 5) The prostatic L.D. activities were decreased to half the normal two weeks after castration. The administration of sex hormones (i.e., estrogen, androgen and progesterone) acted inclusively upon elevating the level f activities. Androgen, in general, was the most effective to restore the activity to the level of pre-castrated state. 6) The prostatic M.D. activities were also decreased to half the normal two weeks after castration. The administration of sex hormones acted inclusively upon elevating the level ofthe activities. Androgen had a remarkable effect in elevating the M.D. activities, which showed twice the precastration level. In this study, it is concluded that L.D. and M.D. activities are present in the testis and the prostate. They are induced and activated by the administration of sex hormones, of which androgen has the most remarkable effect, and estrogen and progesteronehave less effect, while hydrocortisone and DOCA are ineffective in some cases orinhibitory in others.


Sujet(s)
Humains , Mâle , Lapins , Castration , Acétate de désoxycorticostérone , Oestrogènes , Hormones sexuelles stéroïdiennes , Hydrocortisone , Malate dehydrogenase , Oxidoreductases , Progestérone , Prostate , Testicule
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