Enzymatic activity of a soil profile in the Sudan Gezira

1969 ◽  
Vol 30 (1) ◽  
pp. 153-156 ◽  
Author(s):  
M. M. Musa ◽  
N. O. Mukhtar
2020 ◽  
Author(s):  
Gorbov Sergey ◽  
Skripnikov Pavel ◽  
Bezuglova Olga

<div> <p>Soil water-soluble organic matter (WSOM) is the most dynamic and least stable component of humus. It takes a direct part both in leading soil processes and in the formation of effective soil fertility. Its components are involved in the creation of a water-resistant structure, also exhibit physiological activity, and be of service as energy material by microorganisms. The total content of organic matter in the soils of the Rostov agglomeration varies widely: from 1.5 to 7.0%. Long-term studies of soils of the Rostov agglomeration forest-park zones showed that the organic carbon content in these soils increases under tree vegetation. This is due to changes in microclimate conditions and the associated longer period of vegetation of herbaceous vegetation. The WSOM content was obtained by summing the results of cold and hot extraction in natural soils. Its gradually decreases with depth repeating the profile dynamics of the organic carbon content in general. The surface horizons of native chernozems in a forest park and in a virgin land have the highest content of WSOM. It can be concluded that the WSOM pool is directly proportional to the stock of incoming plant residues. The maximum of extracellular enzymes activity was obtained in upper most biogenic soil horizons in the natural city soils. The highest activity was record for the enzyme, which is responsible for the nitrogen cycle (arginine-aminopeptidase (Agr)) and for the phosphorus cycle (acid phosphatase (Pho)). The enzymes activity decreases down the soil profile. </p> </div><div> <p>For anthropogenically transformed soils, the WSOM profile distribution indicates a peculiar two-member structure of soil profile. The transformed upper urbiс horizons was demonstrate the absence of any patterns in its distribution. In the buried horizons of Technosols, were have the same profile trends and the same absolute values of the organic carbon content such us presented in native chernozems. Despite the high humus content in natural soils (5–7%), most of it is strongly associated with calcium ions. As a result, WSOM has values not exceeding 0.14% of the soil as a whole, or 4% in terms of organic carbon. For the urban horizons of anthropogenically transformed soils, WSOM values are not exceeding 0.04% of the soil, or about 2% in terms of organic carbon. The inversions of enzyme activity are often observed in anthropogenically transformed soils. The enzymatic activity is higher in buried humus-accumulative horizons of urbostratozems than in overlying horizons of the urbic. </p> </div>


Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6364
Author(s):  
Anna Piotrowska-Długosz ◽  
Mirosław Kobierski ◽  
Jacek Długosz

Most studies on soil enzymes are focused on the upper horizons of the soil profile, even though they transform the soil organic matter at every depth of the soil profile. The aim of this work was to investigate the distribution of β-glucosidase (GLU), nitrate reductase (NR), urease (UR), phosphatase (PHA), dehydrogenase (DHA) and catalase (CAT) activity through 14 trunked soil profiles of the Luvisols formed from a glacial till. The content of microbial biomass carbon (MBC) as well as physicochemical properties such as organic carbon (CORG), total nitrogen (NTOT), available P, K and Mg, soil density and porosity, pH in KCl and fractional composition were also studied. In general, enzymatic activity was highest in the top 30 cm layer of the profiles and decreased progressively towards the deeper horizons. The exceptions were the NR activity, which was active only in the Ap horizon and whose activity decreased sharply to nearly zero in the Bt horizon and parent rock, and the PHA activity, which was highly active even in the parent rock depth. The decreased availability of carbon and nutrients was the main driver of decreases in microbial abundance and enzymatic activity with depth. The enzymatic activity, when expressed on a CORG and MBC basis, behaves differently compared to the activity expressed on a soil mass basis. The activity decreased (NR), increased (PHA, UR), showed no clear pattern (GLU) or the changes were not significant (DHA, CAT). The content of CORG, NTOT, K and PAVAIL generally decreased with depth, while for Mg, there was no clear direction in the profile distribution. Future studies to characterize the substrate distribution within the soil profile and enzyme stability will provide further insight into the controls on nutrient cycling and related enzymes throughout the soil profiles.


1959 ◽  
Vol 36 (2) ◽  
pp. 193-201 ◽  
Author(s):  
Julius A. Goldbarg ◽  
Esteban P. Pineda ◽  
Benjamin M. Banks ◽  
Alexander M. Rutenburg

1977 ◽  
Vol 38 (02) ◽  
pp. 0475-0485 ◽  
Author(s):  
Anna D. Borsodi ◽  
Ralph A. Bradshaw

SummaryThe plasma of individuals, hetero- or homozygous for α1-antitrypsin deficiency, contains greatly decreased amounts of antithrombin activity as assayed against factor Xa. However, heparin stimulation of the residual antithrombin activity is observed, which is comparable to that of normal plasma. Antithrombins isolated from both normal and α1-antitrypsin deficient plasma by a simplified procedure are indistinguishable in both properties and yields. The microheterogeneity observed on isoelectric focusing of both preparations can be eliminated by treatment with neuraminidase. Neither purified human antithrombin nor α1-antitrypsin, when assayed against bovine trypsin, is stimulated by heparin. These results clearly establish the unique natures of antithrombin and α1-antitrypsin and show that about 75% of the antithrombin activity measured in normal plasma is due to α1-antitrypsin. Estimates of anti thrombin III activity in normal plasma by assays dependent on enzymatic activity can probably be obtained only in the presence of heparin.


1997 ◽  
Vol 78 (05) ◽  
pp. 1372-1380 ◽  
Author(s):  
André L Fuly ◽  
Olga L T Machado ◽  
Elias W Alves ◽  
Célia R Carlinis

SummaryCrude venom from Lachesis muta exhibited procoagulant, proteolytic and phospholipase A2 activities. A phospholipase A2, denoted LM-PLA2 was purified from L. muta venom to homogeneity, through a combination of chromatographic steps involving gel-filtration on Sephacryl S-200 HR and reverse phase chromatography on a C2/C18 column. LM-PLA2 presented a single polypeptide chain with an isoelectric point at pH 4.7 and apparent molecular weight of 17 kDa. Partial aminoacid sequence indicated a high degree of homology for LM-PLA2 with other PLA2 from different sources.LM-PLA2 displayed a potent enzymatic activity as measured by indirect hemolysis of red blood cells but it was neither lethal when injected i.p. into mice nor did it present anticoagulant activity. Furthermore, LM-PLA2 displayed a moderate inhibitory activity on the aggregation of rabbit platelets induced by low levels of ADP, thrombin and arachidonate. In contrast, platelet aggregation induced by high doses of collagen was strongly inhibited by LM-PLA2 as well as ATP-release. Treatment of the protein with p-bromophenacyl bromide or 2-mercapto-ethanol, as well as thermal inactivation studies, suggested that the platelet inhibitory effect of LM-PLA2 is dependent on its enzymatic activity. Thus, the platelet inhibitory activity of LM-PLA2 was shown to be dependent on the hydrolysis of plasma phospholipids and/or lipoproteins, most probably those rich in phosphatidylcholine. Surprisingly, lyso-phosphatidylcholine released by LM-PLA2 from plasma was shown to preferentially inhibited collagen-induced platelet aggregation, in contrast to other PLA2s, whose plasma hydrolytic products indistinctly affect platelet’s response to several agonists.


2015 ◽  
Vol 2 (2) ◽  
pp. 148-158
Author(s):  
Surianto

Spodosol soil of Typic Placorthod sub-group of East Barito District is one of the problem soils with the presence of hardpan layer, low fertility, low water holding capacity, acid reaction and it is not suitable for oil palm cultivation without any properly specific management of land preparation and implemented best agronomic practices. A study was carried out to evaluate the soil characteristic of a big hole (A profile) and no big hole (B profile) system and comparative oil palm productivity among two planting systems. This study was conducted in Spodosol soil at oil palm plantation (coordinate X = 0281843 and Y = 9764116), East Barito District, Central Kalimantan Province on February 2014, by surveying of placic and ortstein depth and observing soil texture and chemical properties of 2 (two) oil palm's soil profiles that have been planted in five years. Big hole system of commercial oil palm field planting on the Spodosol soil area was designed for the specific purpose of minimizing the potential of a negative effect of shallow effective planting depth for oil palms growing due to the hardpan layer (placic and ortstein) presence as deep as 0.25 - 0.50 m. The big hole system is a planting hole type which was vertical-sided with 2.00 m x 1.50 m on top and bottom side and 3.00 m depth meanwhile the 2:1 drain was vertical-sided also with 1.50 m depth and 300 m length. Oil palm production was recorded from the year 2012 up to 2014. Results indicated that the fractions both big hole profile (A profile) and no big hole profile (B profile) were dominated by sands ranged from 60% to 92% and the highest sands content of non-big hole soil profile were found in A and E horizons (92%). Better distribution of sand and clay fractions content in between layers of big hole soil profiles of A profile sample is more uniform compared to the B profile sample. The mechanical holing and material mixing of soil materials of A soil profile among the upper and lower horizons i.e. A, E, B and C horizons before planting that resulted a better distribution of both soil texture (sands and clay) and chemical properties such as acidity value (pH), C-organic, N, C/N ratio, CEC, P-available and Exchangeable Bases. Investigation showed that exchangeable cations (Ca, Mg, K), were very low in soil layers (A profile) and horizons (B profile) investigated. The low exchangeable cations due to highly leached of bases to the lower layers and horizons. Besides, the palm which was planted on the big hole system showed good adaptation and response positively by growing well of tertiary and quaternary roots that the roots were penetrable into deeper rooting zone as much as >1.00 m depth. The roots can grow well and penetrate much deeper in A profile compared to the undisturbed hardpan layer (B profile). The FFB (fresh fruit bunches) production of the non-big hole block was higher than the big hole block for the first three years of production. This might be due to the high variation of monthly rainfall in-between years of observation from 2009 to 2014. Therefore, the hardness of placic and ortstein as unpenetrable agents by roots and water to prevent water loss and retain the water in the rhizosphere especially in the drier weather. In the high rainfall condition, the 2:1 drain to prevent water saturation in the oil palm rhizosphere by moving some water into the drain. Meanwhile, the disturbed soil horizon (big hole area) was drier than un disturbance immediately due to water removal to deeper layers. We concluded that both big hole and 2:1 drain are a suitable technology for Spodosol soil land especially in preparing palms planting to minimize the negative effect of the hardpan layer for oil palm growth.


TAPPI Journal ◽  
2017 ◽  
Vol 16 (10) ◽  
pp. 559-564 ◽  
Author(s):  
ZHEN WANG ◽  
PINGPING BIN ◽  
YING LIU ◽  
YU LIU ◽  
GUIHUA YANG ◽  
...  

Epoxidized dialdehyde cellulose (EDC) was prepared and grafted with melamine to obtain melamine grafted epoxidized dialdehyde cellulose (EDC-melamine); the products were characterized by various methods and were used as carriers to immobilize laccase. Results show EDC-melamine can immobilize laccase effectively and have higher enzymatic activity compared with EDC. Furthermore, the enzymatic activity of EDC-melamine was found to be as high as 865 U•mg-1, compared with 140U•mg-1 for EDC. The removal efficiency of 2,4-dichlorophenol (2,4-DCP) for EDC-melamine immobilized laccase was about 71.5% at 40°C for 4 h at 10.0 mg•L-1 and dosage of laccase = 0.2 g/L. The removal efficiency can remain greater than 63%, even after six cycles.


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