scholarly journals Effect of heavy metals on enzymes production by Hebeloma crustuliniforme

2014 ◽  
Vol 31 (2) ◽  
pp. 181-189 ◽  
Author(s):  
Hanna Dahm ◽  
Edmund Strzelczyk

Studies were carried out in order to dętermine the effect of some heavy metals (Cu, Cd, Pb, Zn) on the production of enzymes (cellulases, peetinases. proteases) by ectomycorrhizal fungus <i>Hebeloma crusliliniforme</i> (Buli.: Fr.) Quél. All the heavy metals inhibited the general enzymatic activity regardless of the source of carbon used. The metals reduced the egzocellulolytic activity more in media with cellulose powder than with CMC (carboxymethylocellulosc). Among pectolytic enzymes heavy metals most strongly inhibited polygalacturonase (PG). The heavy metals did not harmful affect the activity of pectate lyase (PGL). Proteolytic activity of <i>Hebeloma crustuliniforme</i> was leasi affected by zinc (Zn). The degree of inhibition of enzymes by heavy metals can be presented in the following order Pb < Zn < Cd <Cu.

1956 ◽  
Vol 33 (2) ◽  
pp. 311-324
Author(s):  
R. H. DADD

1. In Tenebrio secretion of protease occurs spontaneously after moult and adult emergence, and in response to feeding in the active larva and mature adult. Damp cellulose powder or water are effective in increasing secretion in the adult. 2. Since little enzyme is accumulated in the epithelial tissue when the total midgut enzyme is greatly increased, it is inferred that synthesis and discharge are interdependent. When synthesis (as indicated by comparatively high tissue enzyme) is accelerated, growth of the midgut epithelium occurs. 3. In starved Dytiscus protease is accumulated in the midgut tissue. Within one hour of feeding it is largely discharged into the crop. Protease recurs in the midgut tissue in a few hours, but remains low so long as the crop contains undigested material. When the crop is empty, discharge ceases and enzyme is again accumulated in the epithelium. Thus the process of discharge appears to be independent of synthesis. 4. The secretory mechanisms of Tenebrio and Dytiscus are discussed in relation to their feeding habits.


2014 ◽  
Vol 16 (2) ◽  
pp. 58
Author(s):  
Arum Krisna Miranti ◽  
MG Isworo Rukmi ◽  
Agung Suprihadi

Leaf litter is one kind of substrate which is good for mold’s growth because of its organic matters content particularly cellulose. Research on mold diversity on Talok (Muntingia calabura L.) leaf litter which grow abundance at Sukolilo Barat Village, Labang Subdistrict, Bangkalan, Madura was conducted in order to determined the diversity and to isolate xerophilic mold as well as to examined the enzymatic activity of the isolates. The isolation has been done by direct and indirect method on DG18 agar, MEA, and OA from three samples which is taken purposively. The enzyme activities observed were cellulolytic, amylolitic and proteolytic at 310C temperature. The results showed that 24 isolates found were come from 3 genus i.e. Aspergillus, Curvularia and Fusarium. The Aspergillus was the largest number found. The Shannon-Wiener Index of Diversity showed that the diversity of three leaf litter samples categorized medium. The highest cellulolytic, amylolitic and proteolytic activity at 310C incubation were showed by A. tamarii (ISM 1), A.aculeatus (ISM 10) , A. terreus sp. 3 (ISM 17) respectively. Keywords : Diversity, mold, talok litter leaf, Madura


1986 ◽  
Vol 64 (11) ◽  
pp. 2753-2757 ◽  
Author(s):  
A. Tyminska ◽  
F. Le Tacon ◽  
J. Chadoeuf

The objective of this study was to determine the different effects of three ectomycorrhizal fungi (Laccaria laccata, Hebeloma crustuliniforme, and Thelephora terrestris) on the growth and mineral nutrition of Pinus silvestris at different levels of soluble phosphorus. Even a low intensity of infection by Laccaria laccata stimulated Pinus silvestris growth greatly. The ability of this ectomycorrhizal fungus to increase Pinus silvestris growth seemed to be more related to its capacity to produce growth substances than to its capacity to stimulate phosphorus uptake. The poor efficiency of Hebeloma crustuliniforme compared with Laccaria laccata at any level of phosphorus could result from differences in diversion of carbohydrates from the host to fungal structures.


2013 ◽  
Vol 39 (3) ◽  
pp. 23-32 ◽  
Author(s):  
Joanna Lemanowicz ◽  
Agata Bartkowiak

Abstract The paper presents the research results for the soils sampled from the area located in the eastern part of the Chodzieskie Lakes, between the Middle Noteć River Valley and the Wełna River Valley, the right tributary of the Warta River. The research involved 7 soil samples from the surface horizons, allocated to the cultivation of various plant species (cereals and vegetable crops). The following were determined in the soil material: the content of phytoavailable forms of selected heavy metals Zn, Cu, Pb, Ni, Fe and Mn, active and available to plants phosphorus against the activity of selected oxydo-reduction and hydrolytic enzymes. The soil under the vegetable crops showed a very high richness in phosphorus available to plants, which must have been related to an intensive fertilisation. There were identified relatively low contents of the available forms of the heavy metals investigated, the fact that points to their natural content in soil, which triggered the inhibition of neither the oxydo-reduction nor hydrolytic enzymes.


2016 ◽  
Vol 17 (3-4) ◽  
pp. 107-111
Author(s):  
T. A. Zamesova

Heavy metals, especially their large concentration, is toxic for all living creatures because they are accumulating in the living things tissues. Theirs excessive levels evoke coagulation of proteins that cause immediate death of cells. Heavy metals get into the ground by different ways: directly because of using, precipitation, industrial pollution. Their impacts may be either time limited and have low toxicity or, alternatively, it may be long-termed and expressing the pollutants' ability to accumulate them in the body and supply chains. In the edaphotop block of land biogeocenosis most of the transformation processes begin with soil degradation ones. This leads to disruption of soil-forming process cycle of matter and biological productivity of systems. Optimization of a particular system or a block is possible only by acting on their biological relations, which is responsible for managing the system. Distortion or optimization of relations occurs with the animals environmental-forming, the component of which is animals burrow activity. As a result of it, water and chemicals are being reallocated in soil depths, thermal and aeration modes are changed, formed typical zoogenous micro relief with specific physical and chemical properties of the soil. This improves the living conditions of soil micro-organisms. Last ones are involved in soil enzyme activity forming. Enzymes involved in important biochemical processes: synthesis and humus decomposition, hydrolysis of organic compounds, the schedule remains of plants and microorganisms and converted them available to fixation, fix loose items, are actively involved in the cycling of essential elements for plants, in oxidation renewable reactions, etc. It is possible to determine the extent of microorganism’s activity by means of indexes of soil proteolytic activity. Conducted studies of the impact for animals burrow activity on the soils proteolytic activity for artificial forest under conditions of heavy metal pollution. Control plots were contaminated by lead with concentrations of 32; 160; 320 mg/kg of soil, which correspond to the maximum permissible concentration of 1; 5; 10 MAC. Samples were taken at 1st, 3rd and 15th months after contamination; proteolytic activity was determined by the Mishustin application method. Current proteolytic activity of soil is determined in vivo. It is the result of microorganism’s vital functions. And in turn can be an indicator of microbial activity. Contamination of lead depressing vital functions for soil microorganisms. This effect is more noticeable in the first month after contamination. The characteristic dependence of the soil proteolytic activity on metal concentration was observed also, the higher the MPC, the lower proteolytic activity level. The characteristics' dependence of soil proteolytic activity on metal concentration were also observed: the higher MPC, the lower the activity level. It was shown that on the mole rats burrows-dug with lead contaminated the medium proteolytic activity level exceeded control 1.9; 1.76 and 1.53 times respectively, at 1st; 3rd and 15th months after contamination. Based on this we can say that burrowing activity of animals inhibits inhibitory effect of heavy metals and plays an important role in the self-cleaning environment.


Biochar ◽  
2021 ◽  
Author(s):  
Nahid Azadi ◽  
Fayez Raiesi

AbstractSoil amendment with biochar alleviates the toxic effects of heavy metals on microbial functions in single-metal contaminated soils. Yet, it is unclear how biochar application would improve microbial activity and enzymatic activity in soils co-polluted with toxic metals. The present research aimed at determining the response of microbial and biochemical attributes to addition of sugarcane bagasse biochar (SCB) in cadmium (Cd)-lead (Pb) co-contaminated soils. SCBs (400 and 600 °C) decreased the available concentrations of Cd and Pb, increased organic carbon (OC) and dissolved organic carbon (DOC) contents in soil. The decrease of metal availability was greater with 600 °C SCB than with 400 °C SCB, and metal immobilization was greater for Cd (16%) than for Pb (12%) in co-spiked soils amended with low-temperature SCB. Biochar application improved microbial activity and biomass, and enzymatic activity in the soils co-spiked with metals, but these positive impacts of SCB were less pronounced in the co-spiked soils than in the single-spiked soils. SCB decreased the adverse impacts of heavy metals on soil properties largely through the enhanced labile C for microbial assimilation and partly through the immobilization of metals. Redundancy analysis further confirmed that soil OC was overwhelmingly the dominant driver of changes in the properties and quality of contaminated soils amended with SCB. The promotion of soil microbial quality by the low-temperature SCB was greater than by high-temperature SCB, due to its higher labile C fraction. Our findings showed that SCB at lower temperatures could be applied to metal co-polluted soils to mitigate the combined effects of metal stresses on microbial and biochemical functions.


1975 ◽  
Vol 21 (9) ◽  
pp. 1362-1368 ◽  
Author(s):  
P. M. Cino ◽  
R. P. Tewari

The physiochemical characteristics of the intracellular proteolytic enzymes of Oidiodendron kalrai, a neuropathogenic fungus, were studied. The organism in the yeast phase was grown in a semisynthetic medium containing 1% tryptone, at 37 °C for 48 h, on a gyrotory shaker. The crude extract was prepared by breaking the cells in a French pressure cell and the proteolytic activity was tested against biological substrates. The cell-free extract hydrolyzed casein, hemoglobin, lactalbumin, gelatin, elastin, collagen, and purified rabbit renal basement membrane to various degrees. Optimal proteolytic activity was observed at pH 6 and at 32 °C. Calcium and EDTA did not affect the enzymatic activity; however, activity was partially inhibited by sulfhydryl-blocking agents and by heat-inactivated horse, calf, and human serum. The extract was totally inactivated by exposure to a temperature of 70 °C for 60 min. Storage at −76 °C or −15 °C for 6 months or at 4 °C for 4 weeks did not affect protease activity.


2006 ◽  
Vol 97 (13) ◽  
pp. 1498-1502 ◽  
Author(s):  
Christopher Malley ◽  
Jaya Nair ◽  
Goen Ho

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