scholarly journals Organic amendments alleviate early defoliation and increase fruit yield by altering assembly patterns and of microbial communities and enzymatic activities in sandy pear (Pyrus pyrifolia)

AMB Express ◽  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yalong Kang ◽  
Xiangrui An ◽  
Yanwei Ma ◽  
Shaomin Zeng ◽  
Shangtao Jiang ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Microbial Communities ◽  
Soil Ph ◽  
Southern China ◽  
Nutrient Concentrations ◽  
Available Phosphorus ◽  
Pyrus Pyrifolia ◽  
Total Enzyme Activity ◽  
The Impact ◽  
Total Enzyme

AbstractSevere early defoliation has become an important factor restricting the development of the pear industry in southern China. However, the assembly patterns of microbial communities and their functional activities in response to the application of bioorganic fertilizer (BIO) or humic acid (HA) in southern China’s pear orchards remain poorly understood, particularly the impact on the early defoliation of the trees. We conducted a 3-year field experiment (2017–2019) in an 18-year-old ‘Cuiguan’ pear orchard. Four fertilization schemes were tested: local custom fertilization as control (CK), CK plus HA (CK-HA), BIO, and BIO plus HA (BIO-HA). Results showed that BIO and BIO-HA application decreased the early defoliation rate by 50–60%, and increased pear yield by 40% compared with the CK and CK-HA treatments. The BIO and BIO-HA application significantly improved soil pH, available nutrient content, total enzyme activity and ecosystem multifunctionality, and also changed the structure of soil bacterial and fungal communities. The genus Acidothermus was positively correlated with the early defoliation rate, while the genus Rhodanobacter was negatively correlated. Additionally, random forest models revealed that the early defoliation rate could be best explained by soil pH, ammonium content, available phosphorus, and total enzyme activity. In conclusion, application of BIO or BIO mixed with HA could have assembled distinct microbial communities and increased total enzyme activity, leading to significant improvement of soil physicochemical traits. The increased availability of soil nutrient thus changed leaf nutrient concentrations and alleviated the early defoliation rate of pear trees in acid red soil in southern China.

scholarly journals Two-Step Production of Neofructo-Oligosaccharides Using Immobilized Heterologous Aspergillus terreus 1F-Fructosyltransferase Expressed in Kluyveromyces lactis and Native Xanthophyllomyces dendrorhous G6-Fructosyltransferase

Catalysts ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 673 ◽  
Author(s):  
Burghardt ◽  
Baas ◽  
Gerlach ◽  
Czermak
Keyword(s):  
Response Surface Methodology ◽  
Enzyme Activity ◽  
Reaction Time ◽  
Aspergillus Terreus ◽  
Kluyveromyces Lactis ◽  
Xanthophyllomyces Dendrorhous ◽  
Initial Concentration ◽  
Total Enzyme Activity ◽  
Glycosidic Bonds ◽  
Total Enzyme

Fructo-oligosaccharides (FOS) are prebiotic low-calorie sweeteners that are synthesized by the transfer of fructose units from sucrose by enzymes known as fructosyltransferases. If these enzymes generate β-(2,6) glycosidic bonds, the resulting oligosaccharides belong to the neoseries (neoFOS). Here, we characterized the properties of three different fructosyltransferases using a design of experiments approach based on response surface methodology with a D-optimal design. The reaction time, pH, temperature, and substrate concentration were used as parameters to predict three responses: The total enzyme activity, the concentration of neoFOS and the neoFOS yield relative to the initial concentration of sucrose. We also conducted immobilization studies to establish a cascade reaction for neoFOS production with two different fructosyltransferases, achieving a total FOS yield of 47.02 ± 3.02%. The resulting FOS mixture included 53.07 ± 1.66 mM neonystose (neo-GF3) and 20.8 ± 1.91 mM neo-GF4.

scholarly journals The effects of starvation and experimental diabetes on phosphoenol-pyruvate carboxykinase in the guinea pig

1977 ◽  
Vol 164 (2) ◽  
pp. 357-361 ◽  
Author(s):  
K R F Elliott ◽  
C I Pogson
Keyword(s):  
Enzyme Activity ◽  
Guinea Pig ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Blood Glucose Concentration ◽  
Mitochondrial Fraction ◽  
Kidney Cortex ◽  
Total Enzyme Activity ◽  
The Mean ◽  
Mean Blood Glucose ◽  
Total Enzyme

1. Approx. 85% of liver phosphoenolpyruvate carboxykinase is associated with the mitochondrial fraction in the fed guinea pig. Enzyme activity is unchanged in diabetes, but doubles during starvation. In contrast with earlier reports, both cytoplasmic and mitochondrial activities were found to be increased. 2. In kidney cortex, total enzyme activity is increased in both starved and diabetic animals. These changes are associated with increases in the cytoplasmic activity alone. 3. In diabetic animals the mean blood-glucose concentration was 23.1 mM. Other blood metabolites were lower than those in the rat, and the animals did not show significant ketosis. 4. Changes in the rates of gluconeogenesis from lactate and propionate paralleled those in phosphoenolpyruvate carboxykinase activity.

scholarly journals IMPACT OF AGRO-ENVIRONMENTAL SYSTEMS ON SOIL EROSION PROCESSES AND SOIL PROPERTIES ON HILLY LANDSCAPE IN WESTERN LITHUANIA

2015 ◽  
Vol 24 (1) ◽  
pp. 60-69 ◽  
Author(s):  
Gintaras JARAŠIŪNAS ◽  
Irena KINDERIENĖ
Keyword(s):  
Soil Erosion ◽  
Soil Properties ◽  
Soil Ph ◽  
Soil Texture ◽  
Sandy Loam ◽  
Chemical Properties ◽  
Available Phosphorus ◽  
Erosion Processes ◽  
Physico Chemical ◽  
The Impact

The objective of this study was to evaluate the impact of different land use systems on soil erosion rates, surface evolution processes and physico-chemical properties on a moraine hilly topography in Lithuania. The soil of the experimental site is Bathihypogleyi – Eutric Albeluvisols (abe–gld–w) whose texture is a sandy loam. After a 27-year use of different land conservation systems, three critical slope segments (slightly eroded, active erosion and accumulation) were formed. Soil physical properties of the soil texture and particle sizes distribution were examined. Chemical properties analysed for were soil ph, available phosphorus (P) and potassium (K), soil organic carbon (SOC) and total nitrogen (N). We estimated the variation in thickness of the soil Ap horizon and soil physico-chemical properties prone to a sustained erosion process. During the study period (2010–2012) water erosion occurred under the grain– grass and grass–grain crop rotations, at rates of 1.38 and 0.11 m3 ha–1 yr–1, respectively. Soil exhumed due to erosion from elevated positions accumulated in the slope bottom. As a result, topographic transfiguration of hills and changes in soil properties occurred. However, the accumulation segments of slopes had significantly higher silt/clay ratios and SOC content. In the active erosion segments a lighter soil texture and lower soil ph were recorded. Only long-term grassland completely stopped soil erosion effects; therefore geomorphologic change and degradation of hills was estimated there as minimal.

Changes in mass and catalytic activity concentrations of aspartate aminotransferase isoenzymes in serum after a myocardial infarction.

1986 ◽  
Vol 32 (3) ◽  
pp. 496-500 ◽  
Author(s):  
A E Niblock ◽  
G Jablonsky ◽  
F Y Leung ◽  
A R Henderson
Keyword(s):  
Myocardial Infarction ◽  
Enzyme Activity ◽  
Catalytic Activity ◽  
Aspartate Aminotransferase ◽  
Left Ventricular ◽  
Peak Activity ◽  
Ventricular Failure ◽  
Total Enzyme Activity ◽  
Activity Concentrations ◽  
Total Enzyme

Abstract We used an RIA and inhibition of enzyme activity to monitor the changes in mass and catalytic concentrations of the aspartate aminotransferase (EC 2.6.1.1;AST) isoenzymes in serum after myocardial infarction. Cytosolic (c-AST) and mitochondrial (m-AST) forms of AST were present in sera from all 38 of our patients. Although the immunological and catalytic concentrations of both isoenzymes correlated well with the size of the infarct, c-AST gave a better measure than did m-AST. About 20% of the total enzyme activity at peak activity was from the mitochondrial isoenzyme. Both isoenzyme activities peak at very nearly the same time, but m-AST has the longer half-life. Immunological evidence of the mitochondrial isoenzyme can be detected in serum for at least eight days after the infarct. The presence of left ventricular failure produces greater serum isoenzyme activities than in those without failure.

scholarly journals The effect of thiamin on the activation of thiamin pyrophosphate-dependent 2-oxoglutarate decarboxylase in Euglena gracilis

1993 ◽  
Vol 292 (2) ◽  
pp. 463-467 ◽  
Author(s):  
S Shigeoka ◽  
Y Nakano
Keyword(s):  
Protein Synthesis ◽  
Enzyme Activity ◽  
Euglena Gracilis ◽  
Total Activity ◽  
Immunoblot Analysis ◽  
Decarboxylase Activity ◽  
Total Enzyme Activity ◽  
Thiamin Pyrophosphate ◽  
Total Enzyme

The effect of thiamin on thiamin pyrophosphate-dependent 2-oxoglutarate (2-OG) decarboxylase activity in Euglena gracilis was investigated. The total activity of 2-OG decarboxylase in thiamin-sufficient cells in 3 times that in thiamin-deficient cells. The addition of thiamin to thiamin-deficient cells causes the total enzyme and holoenzyme activities to increase and reach similar levels to that in thiamin-sufficient cells. Cycloheximide and chloramphenicol, inhibitors of protein synthesis, have no effect on the total enzyme activity. Immunochemical titration and determination of 2-OG decarboxylase mRNA by using an antibody directed against Euglena 2-OG decarboxylase indicate that the increase in the holoenzyme activity of 2-OG decarboxylase is due to activation of pre-existing protein and does not require synthesis of new proteins in thiamin-deficient cells. During the period of the increase in the total activity, the apoenzyme increases and reaches a temporary peak in 2 h. Immunoblot analysis demonstrates that the precursor form (a 65 kDa subunit) of 2-OG decarboxylase in thiamin-deficient cells is more abundant than that in thiamin-sufficient cells and the increase in the apoenzyme by addition of thiamin results from the conversion of the precursor form into the mature form (a 62 kDa subunit).

Effects of pyridostingmine on acetylcholinesterase in different muscles of the mouse

1997 ◽  
Vol 16 (1) ◽  
pp. 18-24 ◽  
Author(s):  
Maxine C Lintern ◽  
Margaret E Smith ◽  
C Brian Ferry
Keyword(s):  
Enzyme Activity ◽  
Extensor Digitorum Longus ◽  
Low Dose ◽  
Control Level ◽  
Extensor Digitorum ◽  
Molecular Forms ◽  
High Dose ◽  
Total Enzyme Activity ◽  
Delayed Effects ◽  
Total Enzyme

1 Pyridostigmine bromide was administered subcuta neously in mice, in a dose of 0.4 or 2.0 ?moles/kg, and the activity of the predominant (G1, G4, and A12) molecular forms of acetylcholinesterase were exam ined in diaphragm, extensor digitorum longus (EDL), and soleus muscles at 3 h, 6 h, 24 h and 5 days. 2 In diaphragm, no effect was apparent after the low dose, but after the high dose there was a reduction in activity of the functional A12 form at 24 h, followed by an increase which had overshot the control level at 5 days. 3 In the fast EDL, after the low dose, all three molecular forms were decreased at 3 h, but had returned to normal by 6 h. This effect was not apparent after the high dose. 4 In the slow soleus the low dose caused a significant increase in total enzyme activity at 5 days, but the high dose caused significant increases in all molecular forms at 3 hours. 5 Thus pyridostigmine had delayed effects on the levels of acetylcholinesterase. The three muscles displayed different sensitivities to the drug, but the changes were consistent with initial inhibition of the activity leading to down-regulation of the enzyme followed by up- regulation, which could overshoot the normal levels.

EXTRACTION OF ENZYMES AND ASSESSMENT OF METABOLISM IN BOVINE RUMEN EPITHELIUM

1982 ◽  
Vol 62 (2) ◽  
pp. 429-438 ◽  
Author(s):  
ROY S. BUSH
Keyword(s):  
Enzyme Activity ◽  
Specific Activity ◽  
Total Activity ◽  
Small Contribution ◽  
Bacterial Protein ◽  
Total Enzyme Activity ◽  
Rumen Epithelium ◽  
Bacterial Enzyme ◽  
Protein Contamination ◽  
Total Enzyme

Papillae collected from the rumens of freshly killed cows were used to estimate the most appropriate methods for enzyme extraction from rumen epithelium and the amount of enzymes in extracts which might be of bacterial origin. Extractions of enzymes from fresh and frozen papillae were compared for the Polytron homogenizer (PT), the Potter-Elvehjem homogenizer (PE), the Waring blender, sonication and acetone powdering plus PE. PE extraction yielded solutions with the highest specific activity for each enzyme. PT extraction released the most protein and total enzyme activity into solution. PT extraction was chosen for the remaining tests because of the high total activity released. Mixed rumen bacteria were homogenized by sonication. Electrophoretic examination of epithelial and bacterial extracts showed differential migration for malate dehydrogenase. Lactate dehydrogenase from the epithelium showed four distinct isozymes whereas the bacterial enzyme showed little distinct band development. Contamination of epithelial extracts by bacterial protein was estimated to be less than 5%. The specific activities of 10 enzymes were found to be similar in epithelial and bacterial extracts so that a small amount of protein contamination would result in only a small contribution to total enzyme activity. The presence of the enzymes assayed in this study plus a number reported in the literature showed that rumen epithelial metabolism is more diverse than previously recognized. Key words: Rumen epithelium, enzymes, extraction

scholarly journals Properties of pyruvate dehydrogenase of rat mammary tissue and its changes during pregnancy, lactation and weaning

1974 ◽  
Vol 142 (1) ◽  
pp. 87-95 ◽  
Author(s):  
Haldane G. Coore ◽  
Barbara Field
Keyword(s):  
Enzyme Activity ◽  
Pyruvate Dehydrogenase ◽  
Time Course ◽  
Active Form ◽  
Mammary Tissue ◽  
Similar Time ◽  
Total Enzyme Activity ◽  
Low Concentrations ◽  
Two Parameters ◽  
Total Enzyme

Pyruvate dehydrogenase of rat mammary tissue showed many of the regulatory properties of the analogous enzyme in other mammalian tissues. It was inactivated in the presence of low concentrations of ATP and this rate of inactivation was slowed if pyruvate or PP1 was also present. Reactivation by Mg2+ in the presence of low concentrations of Ca2+ occurred over a similar time-course. The Km value for Mg2+ in this process was about 2mm. The enzyme was assayed in extracts of freeze-clamped mammary glands removed from pregnant, lactating or recently weaned rats under halothane anaesthesia. Both the initial activity and the activity after full activation (‘total enzyme activity’) were determined. The former parameter, when expressed on a DNA basis, varied within a range of 40 times its lowest value. Maximum total enzyme activity was about 1 unit/g wet wt. The total enzyme activity and the fraction in the active form increased in step from pregnancy to mid-lactation, remained elevated until the end of lactation and then fell steeply within 3 days after weaning. The correlation of these two parameters of enzyme activity may indicate a common regulatory factor or else an interdependence arising from inherent properties of the multi-enzyme complex.

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