Wyniki wyszukiwania - Biblioteka Nauki

1

Adsorption of humic acid on mesoporous carbons prepared from poly- (ethylene terephthalate) templated with magnesium compounds

100%

Karolczyk J. , Mozia S. , Morawski A. W. , Przepiórski J.

Polish Journal of Chemical Technology

|

2012

|

tom Vol. 14, nr 4

95-99

EN

Porous carbons obtained from poly(ethylene terephtalate) contained in a mixture with either MgCO3 or Mg(OH)2 were examined as adsorbents for removal of humic acid from water. Adsorption of the model contaminants is discussed in relation to the textural parameters of the obtained carbon materials. Pore structure parameters of the carbonaceous materials were strongly influenced by preparation conditions including temperature and relative amounts of the inorganics used during preparations as template. Porous carbons prepared revealed a potential to purify water from the model contaminant of high molecular weight. The results presented confirmed a key role of mesoporosity in the adsorption of humic acid. Fluorescence spectroscopy was confirmed to be an useful method to evaluate concentration of humic acid in water.

2

Adsorption of humic acid on mesoporous carbons prepared from poly- (ethylene terephthalate) templated with magnesium compounds

100%

Karolczyk J. , Mozia S. , Morawski A. W. , Przepiórski J.

Polish Journal of Chemical Technology

|

2012

|

tom 14

|

nr 4

95-99

EN

Porous carbons obtained from poly(ethylene terephtalate) contained in a mixture with either MgCO3 or Mg(OH)2 were examined as adsorbents for removal of humic acid from water. Adsorption of the model contaminants is discussed in relation to the textural parameters of the obtained carbon materials. Pore structure parameters of the carbonaceous materials were strongly influenced by preparation conditions including temperature and relative amounts of the inorganics used during preparations as template. Porous carbons prepared revealed a potential to purify water from the model contaminant of high molecular weight. The results presented confirmed a key role of mesoporosity in the adsorption of humic acid. Fluorescence spectroscopy was confirmed to be an useful method to evaluate concentration of humic acid in water.

3

Ultraweak chemiluminescence from gamma-irradiated humic acids

100%

Goraczko W. , Slawinski J.

Nukleonika

|

2004

|

tom Vol. 49, nr 4

143-147

EN

Dried humic acid and its aqueous solution in 0.1 M Na2CO3 were gamma-irradiated with 1 90 kGy from 60Co. Thereafter, a secondary ultraweak radiation in the spectral range of gamma = 340 650 nm from aqueous solutions was recorded as long-lived chemiluminescence (CL). Only for absorbed doses lower than 10 kGy low intensity signals of the CL decay were measurable. For absorbed doses higher than 40 kGy residual flat and weak signals are observed. Humic acid irradiated in the dry form did not reveal statistically significant CL. Absorption spectra (gamma = 240 800 nm) of irradiated solutions indicated the occurrence of a dominant degradation process of the humic acid macromolecular components. The effect of H2O2 and CL enhancers (luminol and lucigenin) on the intensity and kinetics of CL proved the participation of reactive oxygen species and the free radical mechanism in the CL and degradation processes. The dose-effect relationship (i.e. gamma-radiation absorbed dose vs. intensity of gamma-radiation-induced CL) showes a non-linear shape, especially in the range of 1-10 kGy, which suggests complex radical mechanisms. A possible ecological significance of the observed phenomena is briefly discussed.

4

A Case Study in Cianjur West Java, Indonesia: A Correlation Humic and Fulvic Acids with Mineralogical Composition and Physico-Chemical Analysis Using Partial Least Square

100%

Mulyani O. , Joy B. , Kurnia D.

Journal of Ecological Engineering

|

2021

|

tom Vol. 22, nr 5

191--204

EN

Humic and fulvic acids are important materials for the health of the soil. This is related to the capability of humic and fulvic acids as chelating agent for pollutant in soil. The relationship between humic and fulvic acids with that of the soil properties is an important aspect to determine the characteristics of soil. Furthermore, production of humic and fulvic acids is a time-consuming process with several stages. Regarding this problem, the selection of sample size to study humic and fulvic acids is important. The relationship between the soil properties was analysed using the Partial Least Square (PLS) analysis, which is regarded as a solution to solve the analysis of complicated problems by offering a powerful approach. This study aimed to analyse the relationship between humic and fulvic acids, in terms of their mineral and physicochemical properties using the PLS method. The study was carried out in West Java, Indonesia. The results showed that the relationship between the chemical, physical, mineral contents with humic and fulvic acids, affected the negative and positive aspects of the relationship. Humic acids had a weak to good model category (0.269–0.940) with regards to the soil properties, and fulvic acids had a moderate model category (0.495–0.603) against all soil properties. Thus, the PLS method can solve a problem in study relationship between the soil properties with small sample and can help in understanding the soil characteristics in general.

5

Response of Chive (Allium Schoenoprasum L.) Plant to Natural Fertilizers

100%

Algharib A. M. , El-Gohary A. E. , Hendawy S. F. , Hussein M. S.

Journal of Ecological Engineering

|

2021

|

tom Vol. 22, nr 8

200--208

EN

A field experiment was carried out at the Experimental Farm of SEKEM Company in Bilbes, Sharqia Governorate, Egypt during the 2019 season, in order to study the effect of adding compost tea and humic acid on the growth and active ingredient of the chive (Allium schoenoprasum L.) plant. Chive seeds were sown in nursery in August, two months later seedlings were transplanted to permanent soil. The chive plants received two organic fertilizers: the first one was compost tea (0, 100 and 200 ml/L) as main plot, and the second one was humic acid (0, 2 and 4 g/L) as sub plot. The two fertilizers were sprayed twice, 45 and 75 days after sowing. The results revealed that: the applied compost tea significantly increased the growth and yield characteristics as well as oil percentage and yield, compared with untreated plants. The plants treated with compost tea at 200 ml / L produced the maximum mean values of plant height, fresh and dry weights of herb, as well as essential oil yield. However, humic acid at 4 g /L recorded the highest mean values of plant height, fresh and dry weights of herb. On the other hand, humic acid at 2 g/L gave the highest values of essential oil yield. Moreover, the interaction treatments had a significant effect on all traits under study. Thirty compounds of Chive essential oil (EO) were identified by GC-MS analysis, representing from 65.07 to 93.29% of the total EO. The main compounds found were dipropyl disulfide (12.8–35.4%), dipropyl trisulfide (12.9–30.05%), methyl propyl trisulfide (3.80–9.03%) and 1-propenyl propyl disulfide (1.56–10%). The highest amounts of dipropyl disulfide and 1-propenyl propyl disulfide were detected with humic acid at 4 g/L treatment. The treatment of compost tea at 200 ml/L + humic acid at 2 g/L caused the greatest accumulation of dipropyl trisulfide which recorded 30.05%, while the greatest values of methyl propyl trisulfide (9.03%) were recorded as a result of tea compost at 100 ml/L.

6

Ability of Humic Acid in the Absorption of Heavy Metal Content of Lead and Iron in Fish Culture Media

100%

Kiswanto , Wintah

Journal of Ecological Engineering

|

2023

|

tom Vol. 24, nr 5

95--102

EN

The young coal mining pits (young pits) found in West Aceh cause many problems. These pits that form ponds have the potential to be utilized for aquaculture activities. However, the main problem faced in the young pits is the high content of heavy metals. This makes the ponds dangerous for fish farming. Hazardous heavy metals in coal mines are Pb and Fe. Humic acid is one of the materials that can be used to minimize heavy metals and increase water pH. The use of humic acid is more efficient because this technology is easy and cheap and the raw materials are abundant. Humic acid acts as a substance of cation exchange ability found in compost. This research has a long-term goal of making humic acid contained in compost as an alternative material that can minimize heavy metals Pb and Fe, so that it can be used for fish farming activities. The specific objective is to determine the best capacity (dose of humic acid) in minimizing heavy metals and increasing the pH of young pond water in former mines and its effect on fish farming. This research method used a completely randomized design consisting of one factor, namely the dose of humic acid (0 g/L, 2.5 g/L, 5 g/L, 7.5 g/L) and three replications. The results showed that humic acid was able to minimize the content of heavy metals Pb and Fe in coal mine water with the best dose of 5 g/L. The percentage reduction produced was more than 90%. The results of fish rearing using ex-mining pond water treated with humic acid showed that the survival rate and growth rate of fish were higher.

7

Characteristics of humic acids extracted from soils by the capillary electrophoresis

100%

Grzelakowska A. , Christy A.

Polish Journal of Soil Science

|

2003

|

tom 36

|

nr 2

145-152

EN

Humic acids have an important role in the soils. When specific structures of which little is known, are studied, one should use the latest analitycal methods. So far the method of fractionation by electrophoretic mobility has not been very popular in the research studies on humic substances. However, it seems that it is possible to study humification processes and subtle changes in the structure of the material investigated using capillary electrophoresis. On the basis of our experience, some soils representing various types were selected as study material. Electrophoretic separation (by means of buffer solutions with various pH-values) was carried out for the humic acids extracted from the soils selected. The results obtained allowed for the determination of differences in the humic acids structures due to their origin.

8

Effect of cations on ultrafiltration of humic acid and BSA mixture

88%

Madaeni S. S. , Sedeh N. S. , Nobili d. M.

Environment Protection Engineering

|

2005

|

tom Vol. 31, nr 3-4

93-98

EN

In membrane treatment of wastewater containing proteins, humic acid influences the rate and extent of fouling. Cations may increase the tendency of foulants to precipitate due to the changes in intermolecular electrostatic interactions. In this paper, we investigated the effect of cations, including ionic charge and size of hydrated ion, on ultrafiltration of the solutions containing the mixture of HA and bovine serum albumin (BSA). All experiments were carried out in an Amicon batch stirred cell using Amicon XM50, XM300, YM100 ultrafiltration membranes with molecular weight cut-offs of 50 kDa, 300 kDa and 100 kDa, respectively, and Sartorius microfiltration membranes with a nominal pore size of 0.2 mm. Humic substances were extracted from a commercial sample of sphagnum peat from Northern Ireland (Bulrush). In the presence of Ba2+ cations, the HA rejection in the solutions containing HA and BSA was higher compared to the solutions containing Na+ cations. Unlike monovalent cations, divalent cations interact specifically with natural organic matter (NOM) and form metal humic complexes. The binding of divalent cations with natural organic matter is responsible for the development of a dense layer on the membrane surface. Metal cations may also act as a bridge between humic acid and protein. These phenomena result in a higher deposition of substances on the membrane surface leading to lower flux and higher rejection in the presence of divalent metal cations. In addition to the charge, the size of cation plays a role in the deposition process. The solutions containing MgCl2×6H2O are characterizing by higher flux and lower rejection compared to the solution containing BaCl2×2H2O at all ultrafiltration membranes. This phenomenon may be attributed to the size of Mg2+and Ba2+ ions.

9

Effect of Seeding Rate and the Spraying with Licorice Extract in Oil Percentage and Active Ingredients of Caraway (Carum Carvi L.)

88%

Hassan A. Y.

Journal of Ecological Engineering

|

2023

|

tom Vol. 24, nr 4

140--150

EN

A field experiment was conducted to study the effect of three levels of seeding rate (4.7 and 10 kg•h-1) and three concentrations of licorice extract (0.3 and 6 g•L-1) the data were analyzed statistically by using a factorial experiment according to the randomized complete block design (RCBD) with three replicates. The results showed that the seeding rate 7 kg•h-1 gave a significant increase in seeds yield, volatile oil yield, and limonene ratio, which were 1162.6 kg•h-1, 25.6 kg•h-1, and 30.41%, respectively. In turn, seeding rate 4 kg•h-1 gave a higher average of the volatile oil percent and carvone percent, which were 2.3 % and 67.27%, respectively. The results also revealed that spraying of licorice extract with 3 g•L-1 gave significantly influenced in seeds yield and volatile oil yield which were (1016.6 and 23.3 kg•h-1) respectively, whereas the spraying of licorice extract with 6 g•L-1 gave the highest ratio of carvone and limonene which were 29.71% and 67.54% respectively. The interaction between the seeding rate of 7 kg•h-1 and licorice extract with 3 g•L-1 had a significant effect on seeds yield and volatile oil yield, which amounted to (1234.2 and 28.4 kg•h-1), respectively.

10

Removal of natural organic matter from potable water using photo-catalytic membrane reactor

88%

Kumakiri I. , Simon C. , Szczepanowicz K. , Wodka D. , Nowak P. , Szyk-Warszyńska L. , Warszyńsk P.

Physicochemical Problems of Mineral Processing

|

2010

|

tom Vol. 45

73-84

EN

The application of photocatalysis combined with membrane filtration for the oxidation of humic acid substances (HA) which is one of the major natural organic matters (NOMs) is discussed in this paper. Theoretical model shows a potential advantage of photo-catalytic filtration under low flux conditions. Cross-flow filtration is applied for HA removal using a TiO2 membrane under UV conditions. An increase of the flux through the membrane was observed by applying UV light.

11

The influence of ozonation on the activated carbon adsorption of phenol and humic acid

88%

Seredyńska-Sobecka B. , Tomaszewska M.

Polish Journal of Chemical Technology

|

2007

|

tom 9

|

nr 4

107-110

EN

To study the influence of ozonation on the activated carbon adsorption, a model solution containing approximately 8 mg/dm3 of humic acid and approximately 1 mg/dm3 of phenol has been ozonated, and then adsorption kintetics and adsorption isotherm experiments have been performed. The applied ozone doses ranged from 1 to 3 mg O3/dm3, and a contact time was 1 min. In the adsorption experiments, the commercial activated carbon CWZ-30 (Gryfskand Sp. z o.o., Hajnówka, Poland) has been used. Phenol adsorption under equilibrium conditions was determined by the Freundlich isotherm equation, and the modified Freudlich isotherm equation has been employed for the determination of humic acid equilibrium adsorption. The applied oxidation conditions resulted in color, chemical oxygen demand (COD), total organic carbon (TOC) and UV254 absorbance removal, by 4 - 13%, 3 - 6%, 3 - 7%, respectively. After ozonation, phenol concentration decreased by 6 - 23%. These changes in the model solution did not affect the humic acid adsorption, however, they deteriorated phenol adsorption.

12

Model radioisotope experiments on the influence of acid rain on 65Zn binding with humic acid

88%

Koczorowska E. , Mieloch M. , Slawinski J.

Nukleonika

|

2002

|

tom Vol. 47, nr 4

167-171

EN

Acid rain formed first of all from sulphur oxide emitted by natural and anthropogenic sources, may change the biological equilibrium and the metal stoppage in the soil. The model experiments were performed to determine the influence of acid rain on zinc bond with humic acid (HA). The samples were prepared in glass columns with quartz sand and overlaid HA or HA+65Zn radioisotope that simulates natural conditions. Then, solutions of H2SO4 were introduced into the sand HA layer. Zinc was washed with diluted (10 4 10 3 M) sulphuric acid as the simulation of acid rain. The recovery of injected radiotracer ions in eluates was found to depend on pH of simulated acid rain. The results help to evaluate the migration behaviour of zinc in the presence of HA and H2SO4. The model studies illustrate the considerable influence of sulphuric acid on chemical degradation of HA.

13

Content of phenolic compounds in humus acids of forest soil

88%

Banach-Szott M.

Polish Journal of Soil Science

|

2007

|

tom 40

|

nr 1

EN

Theaimof the present paper was to define the qualitative and quantitative composition of phenolic compounds in the extracts of fulvic acids and hydrolyzates of humic acids isolated from forest soil. Forest soil was sampled from the organic horizon (5-3.5 cm – sub-horizon Ol and 3.5-0 cm– sub-horizon Ofh) and mineral horizon every 10 cm (0-50 cm). Phenoliccompounds in fulvic acids (FAs) extracts and humic acids (HAs) hydrolyzates were identified by high performance liquid chromatography (HPLC). The recorded chromatograms showed differences in the composition of phenolic compounds between humic and fulvic acids fractions. The content of those compounds both in extracts of fulvic acids and hydrolyzates of humic acids and V+S+C parameter values decreased together with the sampling depth. The highest values of V+S+C parameter were calculated for extracts of fulvic acids and humic acids hydrolyzates isolated from the organic horizon of forest soil. The share of the vanillyl type in the extracts of humus acids (HAs+FAs) of the subhorizon Ol was close to that of the sum share of the syringyl and cinnamyl type. The greater the depth, the greater the share of vanillyl compounds in the pool of the share of syringyl, cinnamyl and vanillyl compounds.

PL

Celem pracy było określenie składu jakościowego i ilościowego związków fenolowych w ekstraktach kwasów fulwowych i hydrolizatach kwasów huminowych gleby leśnej. Próbki gleby leśnej pobrano z poziomu organicznego (5-3.5 cm – podpoziom Ol i 3.5-0 cm – podpoziom Ofh) oraz z poziomów mineralnych co 10 cm (0-50 cm). Związki fenolowe w ekstraktach kwasów fulwowych (KF) i hydrolizatach kwasów huminowych (KH) oznaczono metodą wysoko sprawnej chromatografii cieczowej (HPLC). Na podstawie przebiegu chromatogramów wykazano różnice składu związków fenolowych między kwasami huminowymi i kwasami fulwowymi. Zawartość związków fenolowych zarówno wekstraktach kwasów fulwowych jak i hydrolizatach kwasów huminowych oraz wartości parametruV+S+C zmniejszały się wraz z głębokością pobrania próbek. Najwyższymi wartościami parametruV+S+C charakteryzowały się ekstrakty kwasów fulwowych i hydrolizaty kwasów huminowych wyizolowane z poziomu organicznego gleby leśnej. W ekstraktach kwasów humusowych (KH+KF) podpoziomu surowinowego udział jednostek wanilinowych był zbliżony do sumy udziału jednostek syryngowych i cynamonowych. Wraz z głębokością zwiększał się udział jednostek wanilinowych w puli udziału jednostek syryngowych, cynamonowych i wanilinowych.

14

Synthesis and properties of model humic substances derived from gallic acid

88%

Slawinska D. , Polewski K. , Rolewski P. , Slawinski J.

International Agrophysics

|

2007

|

tom 21

|

nr 2

15

Considerations on the degradation of hydrophobic organic chemicals in humic acid solutions

88%

Badora A.

Zeszyty Problemowe Postępów Nauk Rolniczych

|

2001

|

tom 476

EN

The aim of this research was to show, that sorption and desorption processes of organic hydrophobic compounds on humic acid fraction can influence the microbial degradation rates of contaminants. This study was carried out in the Netherlands in 1996. Chlorinated benzene (pentachlorobenzene QCB) and a polychlorinated biphenyl (2.5-dichlorobiphenyl) were used as a model compounds.

PL

W niniejszej pracy starano się zwrócić uwagę na wpływ procesów sorpcji i desorpcji hydrofobowych aromatycznych związków organicznych przez frakcję kwasu huminowego substancji organicznej na szybkość procesów biodegradacji tych związków. Eksperyment był wykonany w Holandii w 1996 roku. Jako zwiąki modelowe użyto pentachlorobenzen (QCB) i polichlorobifenyl (2.5-PCB).

16

Eco-Friendly Principles on the Extraction of Humic Acids Intensification from Biosubstrates

75%

Malyushevskaya A. , Koszelnik P. , Yushchishina A. , Mitryasova O. , Mats A. , Gruca-Rokosz R.

Journal of Ecological Engineering

|

2023

|

tom Vol. 24, nr 2

317--327

EN

It is necessary to find innovative ways to improve the environmental performance of production processes and products. The technology of extracting valuable components from raw materials of plant origin is often used in technological processes of the food, pharmaceutical, chemical and other industries. Extraction is the most energy intensive step. The factors contributing to the extraction of humic acids from plant substrates under the action of electric discharge were studied. The purpose of the work was to study the efficiency of humic acids extraction from the biosubstrate under the action of electric discharges. The physical experiment showed that the main factor influencing the intensity of extraction is the degree of grinding of the solid phase of the biosubstrate-water suspension. The efficiency of electric discharge grinding depends on the pressure amplitude at the distance of the inner radius of the chamber and the number of discharge pulses. It was established that the number of chemical reagents (alkalis), usually used in the process of extracting humic acids from peat, can be reduced many times due to the appearance of radicals and peroxide compounds in the peat-water suspension resulting from the action of an electric discharge. The prospects of the non-thermal electric discharge method of intensification of the extraction of humic acids from biosubstrates were determined.

17

Mass-transfer model for humic acid removal by ultrafiltration

75%

Galambos I. , Csiszar E. , Bekassy-Molinar E. , Vatai G.

Environment Protection Engineering

|

2005

|

tom Vol. 31, nr 3-4

145-152

EN

Humic acid (HA) molecules present in the soil dissolve in the water and can be found also in the well water. They have different size, molecular weight and structure. It is important to remove these molecules because they build carcinogenic by-products when they react with disinfectants. Membrane filtration can be an effective method of removing humic acid from water. Earlier experiments have proved that ultrafiltration membranes are proper for this task. The aim of this study was to find a new formula which helps to design a well-water filtration. We needed to model the mass transfer during the membrane filtration and to calculate the mass-transfer coefficient. The calculations were carried out in two ways: by using the results of laboratory measurements and criterial equations and by using heat-transfer analogy. The results reveal that the values measured and calculated are in agreement, the heat-transfer analogy can be applied and the equations are useful for designing the membrane for drinking water treatment.

18

Charakterystyka kwasów huminowych gleb z poziomami rudy darniowej

75%

Pastuszko A. , Pracz J.

Przemysł Chemiczny

|

2012

|

tom T. 91, nr 4

559-563

PL

Przedstawiono wyniki składu pierwiastkowego (C, H, N, O), współczynnika ekstynkcji E₄/E₆ oraz liczby grup COOH i OH kwasów huminowych (KH) gleb z poziomami rudy darniowej oraz dokonano analizy struktury KH przy użyciu analizy spektrofotometrycznej w zakresie IR.

EN

Sixteen samples of Polish ferro-muck, ferro-mucky, ferrohumic and ferro-mucous soils taken from 4 sites (depth up to 48 cm) were studied for elementary compn., extinction (color) index and content of functional groups (COOH, OH). The humic acids from bog iron ore levels contained more C and O but less N and H than those from the surface levels.

19

The comparison of the structure of humic acids from soil amended with different sources of organic matter

75%

Kwiatkowska-Malina J.

Polish Journal of Soil Science

|

2015

|

tom 48

|

nr 1

EN

Soil organic matter (SOM) is an essential soil constituent. The deficiency of SOM is an essential problem in many regions in Poland. Diversity of organic matter and the environment create varying structures and compositions, and thus differences in properties of humic substances (HS) especially humic acids (HAs). It was found that soil amendment with organic matter resulted in improving of soil and HAs properties compared with non-treatment ones. The results obtained provided the following evidences. With respect to HAs: an increasing content of carboxylic groups in HAs from amended soils; a major content of aromatic ring systems; higher carbon, nitrogen, hydrogen, and sulphur and lower oxygen contents comparing to the control; the addition of straw caused an increase of carbon content in HAs particles and, consequently a decrease of the C:H ratio; higher content of oxygen functional groups compared with non-treated ones. Organic matter from straw is more resistant to fast decomposition as compared to compost and it shows higher long-term sorption capacity. Therefore, straw may be an equivalent to natural sources of SOM in terms of agriculture and ecosystems protection.

PL

W zależności od rodzaju egzogennej materii organicznej (obornik, kompost, słoma) wprowadzonej do gleb wyekstrahowane kwasy huminowe charakteryzowały się różnymi właściwościami. Stwierdzono, że w kwasach huminowych wystąpił wzrost zawartości grup karboksylowych i fenolowych, większy udział struktur aromatycznych. W kwasach huminowych z gleb nawożonych stwierdzono większą zawartość węgla, wodoru, azotu i siarki oraz niższą zawartość tlenu w porównaniu do kwasów huminowych z gleb bez dodatku egzogennej materii organicznej. Dodatek słomy spowodował wzrost zawartości węgla w składzie pierwiastkowym kwasów huminowych a w konsekwencji zmniejszenie stosunku C:H. Materia organiczna ze słomy jest bardziej odporna na szybki rozkład w porównaniu z kompostem.

20

Wpływ kwasów huminowych na aktywność metaboliczną buraka cukrowego w warunkach suszy

75%

Rombel-Bryzek A. , Pisarek I.

Proceedings of ECOpole

|

2017

|

tom Vol. 11, No. 1

279--286

PL

Reaktywne formy tlenu (RFT) powstają w komórkach jako produkt uboczny wielu procesów metabolicznych, a ich wytwarzanie nasila się pod wpływem wielu czynników środowiskowych. W pewnych granicach stężeń obecność RFT jest niezbędna do zachowania prawidłowego funkcjonowania komórki, dlatego rośliny wykształciły liczne mechanizmy, których rola polega na utrzymaniu stałego stężenia RFT. Zachwianie równowagi pomiędzy powstawaniem RFT a działaniem ochronnym systemu antyoksydacyjnego prowadzi do stanu zwanego stresem oksydacyjnym. Susza jest głównym czynnikiem ograniczającym wzrost i rozwój roślin. Jednocześnie badania dowiodły, że kwasy huminowe stosowane dolistnie łagodziły negatywne skutki niedoboru wody dzięki specyficznemu aktywowaniu enzymatycznych systemów antyoksydacyjnych. Celem badań była ocena wpływu kwasów huminowych zastosowanych dolistnie na aktywność metaboliczną buraka cukrowego Beta vulgaris L. w warunkach suszy. Badania przeprowadzono w warunkach laboratoryjnych. W materiale roślinnym, który stanowiły rośliny buraka cukrowego, oznaczano aktywność właściwą peroksydazy gwajakolowej (GPOX), stopień peroksydacji lipidów, zawartość chlorofilu a i b. Wyniki ujawniły, że dolistne zastosowanie kwasów huminowych u roślin wzrastających w warunkach suszy nie zwiększa aktywności właściwej GPOX w porównaniu do roślin regularnie podlewanych. Jednocześnie u tych roślin stwierdzono wzrost stopnia peroksydacji lipidów. W badaniach nie stwierdzono wpływu warunków uprawy na zawartość chlorofilu a i b w badanych roślinach.

EN

Reactive oxygen species (ROS) are the byproducts of many metabolic processes and their production is increased under of number of environmental factors. In certain concentration range, the presence of ROS is necessary to maintain proper cell function. Thus, cells have many mechanisms, which role is focused on maintaining a constant concentration of ROS. Imbalance between the formation and action of a protective antioxidant system leads to oxidative stress. Drought is a major limiting factor for plant growth and development. At the same time studies have shown that humic acids foliar application moderated the negative effects of water deficient through activation of the enzymatic antioxidant systems. The aim of the study was to evaluate the effect of humic acid foliar application on the metabolic activity of sugar beet Beta vulgaris L. under drought conditions. Studies were conducted under laboratory conditions. In the plants of sugar beet were determined the specific activity of guaiacol peroxidase (GPOX), lipid peroxidation and chlorophyll a and b content. The results revealed that the humic acid foliar application in plants growing under drought conditions does not increase the specific activity GPOX compared to plants watered regularly. At the same time, found an increase in the degree of lipid peroxidation in these plants. There was no impact of growing conditions on the content of chlorophyll a and b in the studied plants.