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1

Morpho-Physiological and Biochemical Responses of Cymbopogan citratus and Asparagus officinalis L. to Waterlogging and Salinity Stress

Hanif Asma, Sattar Maida, Qiushi Qin, Gul Mah, Shahzad Sobia, Jian Wei, Hassan Muhammad Umair, Al-Khayri Jameel Mohammed, Aldaej Mohammed Ibrahim, Sattar Muhammad Naeem

Journal of Ecological Engineering

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2024

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Vol. 25, nr 2

115--125

EN

Salinity stress is an alarming issue causing a substantial reduction in crop productivity. Waterlogging also limits crop productivity and the extent of both these stresses is increasing due to climate change and global warming. This study investigated the response of Lemongrass and Asparagus grass under salinity stress and waterlogged conditions. The study was comprised of different treatments: control, salinity stress, waterlogged conditions and salinity stress + waterlogged conditions. The results revealed that salinity + waterlogging pressure negatively affected cymbopogan citratus and Asparagus officinalis. The physio-morphological, biochemical attributes, enzymatic antioxidants, and nutrient parameters showed a greater reduction under combined salinity and water waterlogged conditions. Waterlogging caused a marked decrease in root growth, leaves production and plant height of both grasses, compared to the control. Salinity stress also resulted in similar morphological modifications, albeit to a lesser extent. Physiological analysis showed a decline in chlorophyll content and RWC, indicating reduced photosynthetic capacity and water uptake efficiency in response to waterlogging and salinity. Electrolyte leakage, increased significantly under waterlogging and salinity stress, suggesting cellular damage and membrane disruption. C.citratus exhibited greater resilience to waterlogging and salinity compared to A. officinalis. Despite the adverse conditions, C. citratus maintained higher chlorophyll content, RWC, and lower electrolyte leakage, indicating better stress tolerance mechanisms. In conclusion, waterlogging and salinity induced significant morphophysiological modifications in both C. citratus and A. officinalis. However, C. citratus exhibited better tolerance to these stresses, suggesting its potential for cultivation in waterlogged and saline environments.

2

Comparative Analysis of Phenolic and Flavonoid content, Antioxidant, Antibacterial Activities, and Functional Groups of Chemicals from Hypericum perforatum L., and Papaver Rhoeas L. Flower Extracts

Afqir Hajar, Belmalha Saadia, Farihi Ayoub, Elbouzidi Amine, Bouhrim Mohamed, Elrherabi Amal, Boutagayout Abdellatif, Oubihi Asmae, Ouhssine Mohammed

Ecological Engineering & Environmental Technology

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2024

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Vol. 25, iss. 2

88--101

EN

In this study, the authors aimed to compare the phytochemical compounds (polyphenols and flavonoids), antioxidant activity, functional groups present in the compounds (FTIR), and anti-microbial effects, in the aqueous and methanol extracts obtained from flowers of commercial Hypericum perforatum and native Papaver Rhoeas from Morocco. P. Rhoeas L was collected from El Lhaj Kaddour near Meknes, while H. perforatum L was bought in a dried state from a Moroccan herbalist in the same city. Total polyphenols were evaluated using the Folin-Ciocalteu reagent, respectively. The antioxidant activity was assessed via DPPH and antimicrobial effects were tested against six bacteria (Gram– and Gram+). The aqueous and methanol extracts of P. Rhoeas had the highest TPC value (23.67 ± 0.94 mg GAE/g; 15.86 ± 0.65 mg GAE/g) compared to H. perforatum (15.26 ± 1.30 mg GAE/g; 5.50 ± 1.13 GAE/g). The aqueous extract of Papaver Rhoeas exhibited the highest TFC at 14.36 ± 0.49 mg QE/g, while the methanol extract of Hypericum perforatum had the highest 10.65 ± 0.49 mg QE/g in TFC. In contrast, the methanol and aqueous extracts of H. perforatum showed significant zones of inhibition against Staphylococcus aureus (9.5 ± 0.5 mm and 10.17 ± 0.29 mm) and Staphylococcus epidermidis (8.33 ± 0.58 mm and 9.33 ± 0.58 mm) respectively, with a minimum inhibitory concentration was estimated at 10 μL/ml. The FTIR analysis demonstrated that the extracts of both plants are rich in bioactive molecules with potential biological activities and a pharmaceutical industry perspective. Consequently, these Papaver Rhoeas and Hypericum perforatum extracts exhibit antioxidant and antibacterial activities.

3

Olive oil : health benefits and application of the GCMS technique and the LCMS technique for the quantification of the important nutritional components®

Polak-Śliwińska Magdalena

Postępy Techniki Przetwórstwa Spożywczego

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2022

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nr 1

217--232

EN

Olive oil is known for its health properties [88], which has translated into dietary patterns favouring higher consumption, especially in Mediterranean countries. Numerous studies support the claim of olive oil consumption and its potential health benefits, especially in the prevention of cardiovascular disease, diabetes and breast cancer. Olive oil is considered a nutritional product because it contains phenolic compounds (for example, oleuropein and hydroxytyrosol present in extra virgin olive oil) whose health benefits are now widely documented. Several studies have reported anti-inflammatory effects of phenolic compounds. In vitro and in vivo studies have shown, for example, that the phenols present in olive oil are potent antioxidants. Omega-6 fatty acids, which are also present in this product, are an important factor for the metabolism of the human body, for bones, healthy skin and hair. As an essential nutrient, it is necessary to take them from outside. They are found in many foods, especially vegetable oils and nuts. Commonly used techniques for the determination of beneficial substances from olive oil are GCMS and LCMS, and many of the applications already developed allow the analysis of different types of this product with a single method, which certainly makes it possible to precisely assess the levels of various compounds, including the fatty acid content of olive oil in a short time. The aim of this work was to present recent reports related to the beneficial effects of olive oil consumption in humans and to present selected methods and applications for the analysis of several important substances responsible for the beneficial properties of this product.

PL

Oliwa z oliwek jest znana ze swoich właściwości zdrowotnych [88], co przełożyło sę na wzorce żywieniowe, preferujące wyższe jej spożycie, zwłaszcza w krajach śródziemnomorskich. Liczne badania potwierdzają słuszność twierdzenia o spożyciu oliwy z oliwek i jej potencjalnych korzyściach zdrowotnych, zwłaszcza w zapobieganiu chorobom układu krążenia, cukrzycy i rakowi piersi. Oliwa z oliwek jest uważana za produkt odżywczy, ponieważ zawiera związki fenolowe (na przykład oleuropeina i hydroksytyrozol obecne w oliwie z oliwek extra virgin), których korzyści zdrowotne są obecnie szeroko udokumentowane. W wielu badaniach stwierdzono działanie przeciwzapalne związków fenolowych. Badania in vitro i in vivo wykazały chociażby, że fenole obecne w oliwie z oliwek są silnymi przeciwutleniaczami. Kwasy tłuszczowe omega-6, które są również obecne w tym produkcie, stanowią ważny czynnik dla metabolizmu organizmu ludzkiego, dla kości, zdrowej skóry i włosów. Jako niezbędny składnik odżywczy konieczne jest ich pobieranie z zewnątrz. Znajdują się w wielu produktach spożywczych, zwłaszcza w olejach roślinnych i orzechach. Powszechnie stosowanymi technikami oznaczania substancji korzystnie wpływających na organizmy ludzkie pochodzących z oliwy z oliwek jest technika GCMS i LCMS, a wiele z już opracowanych aplikacji umożliwia analizę różnych rodzajów tego produktu przy użyciu jednej metody, co na pewno pozwala na precyzyjną ocenę poziomu różnych związków, w tym ocenę zawartości kwasów tłuszczowych w oliwie z oliwek w krótkim czasie. Celem pracy było przedstawienie najnowszych doniesień związanych z korzystnym wpływem spożycia oliwy z oliwek przez człowieka oraz przedstawieniem wybranych metod i aplikacji do analizy kilku ważnych substancji odpowiedzialnych za dobroczynne właściwości tego produktu.

4

Plant secondary metabolites as defenses : a review

Jusuf Herlina, Elveny Marischa, Azizova Feruza, Shichiyakh Rustem A., Kulikov Dmitriy, Al-Taee Muataz M., Atiyah Karrar K., Jalil Abduladheem T., Aravindhan Surendar

Journal of Water and Land Development

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2022

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no. 55

206--211

EN

Plant secondary metabolites have a variety of functions, including mediating relationships between organisms, responding to environmental challenges, and protecting plants against infections, pests, and herbivores. In a similar way, through controlling plant metabolism, plant microbiomes take part in many of the aforementioned processes indirectly or directly. Researchers have discovered that plants may affect their microbiome by secreting a variety of metabolites, and that the microbiome could likewise affect the metabolome of the host plant. Pesticides are agrochemicals that are employed to safeguard humans and plants from numerous illnesses in urban green zones, public health initiatives, and agricultural fields. The careless use of chemical pesticides is destroying our ecology. As a result, it is necessary to investigate environmentally benign alternatives to pathogen management, such as plant-based metabolites. According to literature, plant metabolites have been shown to have the ability to battle plant pathogens. Phenolics, flavonoids, and alkaloids are a few of the secondary metabolites of plants that have been covered in this study.

5

Distilled Spirit Extraction of Phenolic Antioxidants from Fruit and Vegetable Residues

Ortinero Cesar V., Rafael Rosalie R., Rayos Charmaine Eljie R., Bautista Katherine D. A., Feliciano Mark Aldren M., Natividad Lexter R., Natividad Gaudencio M.

Journal of Ecological Engineering

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2021

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Vol. 22, nr 1

125--131

EN

There is a growing interest in natural antioxidants due to their potential in improving the quality of food and cosmetic products and their health-promoting properties. Distilled spirits contain high amount of ethanol and may be an alternative to the food-grade solvents, while agricultural by-products contain phenolic substances that may have antioxidant properties. This study was therefore conducted to find out if gin, vodka, and tequila flavored spirit, alcoholic beverages with about 40% ethanol, can extract the phenolic compounds from agricultural by-products, and to determine if the extracts possess the antioxidant activity. Peels of ripe banana (Musa acuminata), ripe mango (Mangifera indica), calamansi (Citrofortunella microcarpa), squash (Cucurbita maxima), ripe pineapple (Ananas comosus), purple yam (Dioscorea alata), and sweet potato (Ipomea batatas) were collected, dried, and ground. The phenolic substances in the plant materials were extracted with alcoholic beverages or 40% ethanol. The total phenolic content (TPC) of the extracts was determined by means of UV-Vis spectroscopy using Folin-Ciocalteau reagent and gallic acid as reference compound. The antioxidant activity of the extracts was evaluated through the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay. Butylated hydroxyanisole (BHA) served as positive control in the DPPH assay. Non-linear regression was applied to the DPPH assay data to estimate the values of median effective concentration (EC50). All three alcoholic beverages were able to extract the phenolic materials from the plant samples. However, the ability of vodka and gin to extract the phenolic substances was either statistically comparable or better than 40% ethanol. The results of the DPPH scavenging assay showed that the M. indica peel had the strongest activity, while C. microcarpa had the weakest scavenging activity. At 1000-ppm level, the antioxidant activity of the M. indica peel was comparable with that of BHA, regardless of the solvent used for extraction. Therefore, the M. indica peel can be a source of natural antioxidants and potential substitute to synthetic antioxidants. Both gin and vodka can be used as a substitute for food-compatible solvents.

6

UPLC–PDA–ESI–MS analysis and TLC–DPPH• activity of wheat varieties

Kowalska I., Jedrejek D., Jonczyk K., Stochmal A.

Acta Chromatographica

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2019

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Vol. 31, no. 2

151--156

EN

Wheat is a major crop, an important component of the human diet and important source of animal fodder in the world. Characterization of phenolic profiles of the leading wheat cultivars is important for new opportunities for breeding and eventual commercial production of value-added cultivars rich in beneficial components. A method using ultra-performance liquid chromatography combined with photodiode-array detector–electrospray ion source–mass spectrometry (UPLC–PDA–ESI–MS) has been developed for determination of phenolic compounds contained in twelve winter and thirteen spring wheat varieties. The antioxidant activity was determined by the thin-layer chromatography–2,2-diphenyl-1-picrylhydrazyl (TLC–DPPH•) test with image processing by means of the ImageJ program. Based on retention time, the mass of deprotonated molecule [M−H]− and ultraviolet (UV) spectra, seven phenolic acids, and twelve flavonoids were identified and quantitated in the 80% aqueous methanol extract of the wheat varieties. The average concentrations of total researched compounds were definitely higher in spring wheat cultivars than in winter ones. Varieties Trappe and Kandela showed the most elevated values of total free phenolic acids. Kandela and Ostka Smolicka had the highest content of flavonoids, and isoorientin was detected as the main phenolic in wheat cultivars. Additionally, a correlation between radical scavenging activity and total phenolic acids content was observed. UPLC combined with PDA–ESI–MS could be applied to complete characterization of natural products (e.g., phenolics) in alcoholic extracts from wheat varieties.

7

Chromatographic isolation and structural elucidation of secondary metabolites from the soil-inhabiting fungus Aspergillus fumigatus 3T-EGY

Abdel-Aziz M. S., Ghareeb M. A., Saad A. M., Refahy L. A., Hamed A. A.

Acta Chromatographica

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2018

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Vol. 30, no. 4

243--249

EN

Eight compounds were isolated and identified from the soil-inhabiting fungus Aspergillus fumigatus 3T-EGY, namely, stearic acid (1), α-linolenic acid (2), physcion (3), di-(2-ethylhexyl) phthalate (4), 2,4,5,17-tetramethoxy pradimicin lactone (5), 3,5-dihydroxy-7-O-α-rhamnopyranoyl-2H-chromen-2-one (6), juglanthraquinone A-5-O-d-rhodosamine-(4′→1″)-2-deoxy-d-glucose (4″→1″′)-cinerulose B (7), and micropeptin (8). Their structures were determined on the basis of one-dimensional (1D-) and two-dimensional nuclear magnetic resonance (2D-NMR) [1H-, 13C-NMR, 1H-1H COSY (COrrelated SpectroscopY), and 1H-13C HMBC (Heteronuclear Multiple Bond Correlation) spectroscopy]. Compound 7 showed moderate in vitro antimicrobial activity against three pathogenic strains with inhibition zones values were ranged from 9.0 to 10.66 mm compared to neomycin as a positive control with inhibition zones values were ranged from 14.0 to 19.0 mm.

8

Simultaneous reverse-phase HPLC determination of major antioxidant phenolics in Commelina benghalensis L. tubers

Misra A., Srivastava A., Srivastava S., Rawat A. K. S.

Acta Chromatographica

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2016

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Vol. 28, no. 4

541--554

EN

Commelina benghalensis (Commelinaceae) is widely used as traditional and folklore medicine in India. In the present study, a reverse-phase high-performance liquid chromatography—photodiode array detection (RP-HPLC—PDA) method was developed for the separation, identification, and quantification of bioactive phenolics. Antioxidant potential was also accessed to validate the presence of identified markers. Method was developed on C18 column with 1% formic acid (in water) and acetonitrile as solvent system, and data acquisitions were achieved at wavelength of 285 nm. The developed method was also validated for accuracy, precision, robustness, limit of detection and quantification (LOD and LOQ), repeatability, and recovery according to International Conference on Harmonization (ICH) guidelines. In this method, five phenolics, viz., protocatechuic acid (0.033%), vanillic acid (0.262%), ferulic acid (0.365%), apigenin (0.126%), and kaempferol (0.544%), were quantified in linearity range of 0.2–1.0 μg with correlation coefficient of more than 0.9949. Relative standard deviation (RSD) (%), LOD, LOQ, and recovery (%) are within the acceptable limit. Besides that, methanolic extract shows the inhibition (%) range from 24.45 to 68.75% at 0.02–0.12 mg Ml-1. IC50 of extract was observed at 46.75 μg Ml-1, suggesting the promising activity in methanol extract. Hence, the proposed method for simultaneous quantification of five bioactive phenolics in the tuber of C. benghalensis using HPLC–PDA detection under the specified conditions is specific and accurate, and validation proves its selectivity and reproducibility.

9

The degradation of kraft lignin during hydrothermal treatment for phenolics

Tang K., Zhou X. F.

Polish Journal of Chemical Technology

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2015

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Vol. 17, nr 3

24--28

EN

Kraft lignin was hydrothermally depolymerized at low temperature/short time in water for producing value-added phenolics. The effects of residence time (15, 60 min) and reaction temperature (130, 180, 230ºC) on yields of oils and phenolic compounds were studied in detail. Total oil yield was found to range between 7% and 10%. The compositions of oils were analyzed by GC-MS to confirm the main compound to be guaiacol (2-methoxy phenol) in the range of 12–55% of oil depending on different reaction conditions. The most interesting was the finding that maximum value of total oil yield (10% of kraft lignin) and guaiacol amount (55% of oil) was obtained at 130ºC/15, 60 min which is a low reaction temperature/short time, while the residual kraft lignins were analyzed by FTIR with respect to the conversion mechanism of kraft lignin by this process.

10

UPLC/Q-TOF-MS Analysis for Identification of Hydrophilic Phenolics and Lipophilic Diterpenoids from Radix Salviae Miltiorrhizae

Yang S. T., Wu X., Rui W., Guo J., Feng Y. F.

Acta Chromatographica

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2015

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Vol. 27, no. 4

711--728

EN

A rapid method has been used for simultaneous identification of both hydrophilic and lipophilic compounds from Radix Salviae Miltiorrhizae (RSM, the root of Salvia miltiorrhiza BGE.) by ultra-performance liquid chromatography/quadrupole time-offlight mass spectrometry (UPLC/Q-TOF-MS). A total of 58 compounds extracted by methanol were detected and tentatively identified within 20 min, including hydrophilic phenolics, lipophilic diterpenoids, a verbascose, and several organic acids. These compounds were separated on an Acquity UPLC BEH C18 column and identified based on tandem mass spectrometry (MS/MS) fragmentation patterns under the positive and negative ion modes, respectively. Among them, micranthin B and 9-oxo-10E,12Zoctadecadienoic acid were reported in RSM for the first time. Their fragmentation patterns in electrospray ionization (ESI)—MS/MS spectra were first investigated by matching their accurate molecular masses. This contribution presented one of the first reports on the analysis of hydrophilic phenolics and lipophilic diterpenoids from Radix Salviae Miltiorrhizae using UPLC/Q-TOF-MS. The results demonstrated that UPLC/Q-TOF-MS method could be applied to rapidly and expediently describe and provide comprehensive chemical information for simultaneous analysis of two different polar components in RSM.

11

HPLC, Two-Dimensional TLC Determination of Phenolic Content, and an In Vitro Perspective to Antioxidant Potential of Euonymus verrucosus Scop. Extracts

Kukula-Koch W., Widelski J., Koch W., Głowniak K.

Acta Chromatographica

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2015

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Vol. 27, no. 4

743--754

EN

The presence of phenolic content in overground extracts of Euonymus verrucosus Scop. — commonly growing in Europe — has been reported recently. The chromatographical and spectral data revealed the presence of several simple phenolic acids (gallic, protocatechuic, p-hydroxybenzoic, vanillic, syringic, caffeic, p-coumaric, ferulic, and m-coumaric acids), both as free and conjugated with other secondary metabolites. The comparison of two-dimensional TLC systems on cellulose stationary phases with HPLC— DAD reversed-phase chromatography was performed to assess a cheap and rapid technique in the identification process of major phenolic constituents. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging tests, expressed as IC50, revealed the most beneficial results for the fraction after alkaline hydrolysis and yielded 205 ± 8 μg mL−1.

12

Contents of phenolics and chemical elements in bilberry (Vaccinium myrtillus L.) leaves from copper smelter area (SW Poland)

Mróz L., Demczuk M.

Polish Journal of Ecology

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2010

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Vol. 58, nr 3

475-486

EN

Concentrations of the elements N, P, K, Ca, Mg, Na, S, Fe, Mn, Cd, Co, Cr, Cu, Ni, Pb and Zn were measured in the leaves of bilberry (Vaccinium myrtillus L.) and the soil in which it grew. Concentration of total phenolics in bilberry leaves was also determined. Soil and leaves were sampled at polluted site situated 10-13 km northeast of copper smelter at Głogów (SW Poland) and at a relatively clean site. Soil at the vicinity of the Cu-smelter contained significantly more Cu, Pb, Cd, S, and significantly less Mn, Zn, Fe, Co, Ni than the non-polluted soil. Bilberry leaves from polluted site contained significantly higher concentrations of Cu, Pb, Cd, S, Fe and Cr and significantly lower concentrations of Mn and Zn. Furthermore, they had significantly higher level of total phenolics as compared with bilberry leaves from non-polluted site. Stepwise regression analysis enabled the identification of the leaf variables that best explain the variance pattern of the total foliar phenolics. This method indicated that the level of total phenolics in bilberry leaves increased with increasing concentrations of Cu, Pb, Cd and S, and decreasing level of Mn and Zn in leaves. Total foliar phenolics in bilberry in the investigated area might be a suitable indicator of stress caused by environmental pollution of heavy metal and sulfur.

13

Response of silver birch (Betula pendula Roth.) seedlings to experimental variation in aluminum concentration

Bojarczuk Krystyna, Oleksyn Jacek, Karolewski Piotr, Żytkowiak Roma

Polish Journal of Ecology

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2006

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Vol. 54, nr 2

189-200

EN

The process of soil degradation and destabilization of forest ecosystem by industrial pollution is frequently associated with mobilization of toxic. Al^3+ ions. Both these processes exert a negative influence on tree root systems and may even result in the decline of whole forest stands. One-year-old seedlings of silver birch (Betula pendula Roth.) grown in pots were treated with a range of aluminum sulfate concentrations in order to test the effects of Al on growth, root structure, content of phenolic compounds and mineral nutrition of roots and foliage. Plants exposed to Al concentrations exceeding 50 mg Al dm^-3 had reduced growth, root structure and a substantial increase of Al concentration occurred in foliafe and roots. Concentration of several elements in the foliage and roots declined with increasing Al concentration, including Mg and Ca , and to a lesser extent, P, K, and Na. Most root traits such as root mass or root growth rate were more strongly affected by Al than the foliage. Changes in root Ca, Al and Ca:Al ratio, and root morphology were detected at the lowest Al concentration (50 mg Al dm^-3) indicating usefulness of these traits as early indicators of adverse aluminum effects on plants.

14

Role of anthocyanins in red cabbage seedlings response to copper stress

Posmyk M.M., Dobranowska A., Janas K.M.

Chemia i Inżynieria Ekologiczna

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2005

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Vol. 12, nr 10

1107-1112

EN

The mechanisms enabling plants to tolerance high concentrations of copper in their rhizosphere are still poorly understood. Changes of soluble phenolics, anthocyanin and sinapoyl ester contents in red cabbage seedlings which were grown in presence of Cu[to 2+] were investigated. Lipid peroxidation increased together with Cu[to 2+] concentrations, indicating an acceleration of oxidative process. The concentrations of soluble phenolics, anthocyanin and sinapoyl esters were significantly higher in seedlings grown in presence of lower Cu[to 2+] concentrations and they were in the inverse relation to TBARS content. The present study demonstrates that phenolic compounds possibly act by detoxifying reactive oxygen species or/and reduced their production by Cu[to 2+] binding.

PL

Mechanizmy umożliwiające tolerancję roślin na duże stężenia Cu[do 2+] w ryzosferze są słabo poznane. W niniejszej pracy badano zmiany zawartości rozpuszczalnych fenoli, antocyjanów oraz estrów kwasu synapilowego w siewkach kapusty czerwonej rosnącej w obecności dużych stężeń Cu[do 2+]. Wraz ze wzrostem stężenia Cu[do 2+] wzrastał stopień-utlenienia lipidów błon komórkowych, co wskazuje na stres oksydacyjny. Stężenie rozpuszczalnych fenoli, antocyjanów i pochodnych synapilowych wzrastało w siewkach rosnących w obecności małych stężeń Cu[do 2+] i było odwrotne do zmian w zawartości TBARS. Dane przedstawione w tej pracy sugerują, że związki fenolowe (antocyjany, estry synapilowe) działają jako antyoksydanty i biorą udział w detoksyfikacji reaktywnych form tlenu lub/i ograniczają ich powstawanie przez wiązanie jonów miedzi.

15

Are phenolic compounds essential in protection of red cabbage seedlings against copper stress?

Posmyk M.M., Osmańska J., Janas K.M.

Chemia i Inżynieria Ekologiczna

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2005

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Vol. 12, nr 10

1113-1119

EN

Red cabbage seedlings were grown in presence of copper at different concentrations with L-phenylalanine ammonia-lyase inhibitor, 2-amino-2-indanephosphonic acid (AIP) at concentration 5 M. Copper increased anthocyanins accumulation but together with AIP blocked anthocyanin synthesis and significantly decreased the level of soluble phenolic and synapoil esters, in red cabbage. Lipid peroxidation occurred when the plants were treated with AIP and stressed by carrer. In seedlings treated with 2.5 mM CuSO4 solution rapid and significant SOD and APX activity increase were observed whereas catalase activity diminished. When seedlings were grown in presence of the lower Cu[to 2+] concentrations increase in SOD activity was delayed by 3 days. An increased APX activity did not prevent peroxidation in the tested seedlings. These results may suggest an important role of phenolics in protection of red cabbage seedlings against copper stress.

PL

Siewki kapusty czerwonej rosły w obecności inhibitora amoniakoliazy L-fenyloalaniny, kwasu 2-aminoindan-2-fosfoniowego (AIP) 5 M. W siewkach rosnących w obecności jonów miedzi zwiększała się zawartość antocyjanów, lecz poziom tych związków był zahamowany, gdy siewki rosły wobec Cu[do 2+] z dodatkiem AIP. AIP wraz z miedzią hamowały zawartość estrów kwasu synapilowego i rozpuszczalnych fenoli w siewkach. Miedź z AOP powodowały zwiększenie utleniania błon komórkowych. W siewkach rosnących wobec 2,5 mM CU2+ następował wzrost aktywności SOD i APX, podczas gdy aktywność katalazy obniżała się. Natomiast kiedy siewki rosły wobec mniejszych stężeń Cu[do 2+] wzrost aktywności SOD był opóźniony o 3 dni. Wzrost aktywności APX nie przeszkadzał utlenieniu błon komórkowych siewek rosnących wobec miedzi. Wyniki mogą sugerować ważną rolę antocyjnaów i estrów synapilowych w tolerancji siewek kapusty czerwonej na stres miedzi.

16

Physico-chemistry of phenolic resins wear at sliding friction in water-glycol solutions

Pleskachevsky Yu.M., Zaitsev A.L., Kirilenko V.P.

Tribologia

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2003

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nr 2

81--93

EN

The work presents the investigation results of sliding friction of phenolic resins ih water-alcohol solutions. On the example of water-glycol solutions the basie physical and chemical processes, accompanying friction and wear of phenolics in contact with metal have been revealed. It has been shown, mat friction and wear properties of considered system mainly depend on an associative structures, which types arę determined by concentration of solution, as well as by their chemical interaction with surfaces of contacting materials. Associate structures of water-glycol complexes define the primary mechanism of polymer wear that is expressed by the hydrolysis of ether substances and/or by polycondensation of hydroxyl groups. The metal is subject to corrosive wear with formation of iron hydroxides, alcoholate complexes and metalorganic substances, capable to polymerization. Adsorption of water-glycol complexes by surfaces, diffusion saturation and plasticization of polymer surface layers depend on chemical structure of complexes also.

PL

Praca przedstawia wyniki badań tarcia ślizgowego żywic fenolowych w roztworach wodno-alkoholowych. Znaleziono, wykorzystując roztwory wodno-glikolowe, podstawowe fizyczne i chemiczne procesy towarzyszące tarciu i zużyciu żywic fenolowych w kontakcie z metalem. Pokazano, że tarcie i zużycie rozważanego systemu zależy w głównej mierze od struktur asocjatów, których typy są uzależnione od stężenia w roztworze, oraz od ich chemicznego oddziaływania z kontaktującymi się w tarciu powierzchniami. Struktury asocjatów woda-glikol decydują o głównym mechanizmie zużycia polimerów, który można przedstawić jako hydrolizę grup eterowych lub plikondensację grup hydroksylowych. Metal poddawany jest zużyciu korozyjnemu, które prowadzi do powstania tlenków żelaza, kompleksów alkoholanowych oraz związków metaloorganicznych, które są zdolne do polimeryzacji. Chemiczna struktura kompleksów ma również wpływ na ich adsorpcję oraz uplastycznienie powierzchni polimerów.

17

Wpływ związków powierzchniowo czynnych na równowagi ekstrakcyjne wybranych układów

Pająk M., Kurczewski B., Skrzypiński W., Kołek A.

Inżynieria Chemiczna i Procesowa

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2002

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T. 23, z. 4

573-581

PL

Poddano analizie wpływ fenolu, p-krezolu i 2,4-ksylenolu na krytyczne stężenie micelarne (CMC) wodnych roztworów bromku cetylotrimetyloamonowego (CTAB). Badania wykonano metodą tensjometryczną w temperaturze 25 stopni C. Stwierdzono zmniejszenie CMC w obecności fenoli. Największe zmniejszenie CMC zaobserwowano dla związku najbardziej hydrofobowego - 2,4-ksylenolu. Doświadczalnie określono wpływ CTAB na równowagi ekstrakcyjne trzech wybranych układów: woda-fenol-toluen, woda-p-krezol-toluen, woda-2,4-ksylenol-toluen. Stwierdzono, że rodzaj substancji ekstrahowanej wpływa na współczynniki podziału w zbadanych układach. Największa zmiana współczynnika podziału w obecności CTAB występuje w układzie: woda-2,4-ksylenol-toluen.

EN

The influence of phenol, p-cresol, and 2,4-xylenol on the critical micelle concentration (CMC) in aqueous solutions of CTAB using tensiometry method at 25 degree C has been investigated. Decreasing of CMC in the presence of phenolic compounds, especially for most hydrofobic 2,4-xylenol was observed. The influence of CTAB concentrations on the water.phenol.toluene, water.p-cresol.toluene, and water .2,4-xylenol.toluene equilibria were presented. The greatest reduction of the partition coefficient for water.2,4-xylenol.toluene extraction system has been confirmed.