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Antyoksydacyjne działanie ekstraktów pochodzenia roślinnego

Kosińska Edyta, Sadlik Julia, Krzysztoń Karolina

Inżynieria Materiałowa

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2024

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Vol. 45, nr 2

17--26

PL

W dzisiejszych czasach wzrasta zainteresowanie związkami, jakimi są przeciwutleniacze, ze względu na ich biologiczną aktywność – zdolność antyoksydacyjną. Znajomość zawartości substancji aktywnych w różnych produktach jest niezwykle istotna w dbaniu o swoje zdrowie i prewencje chorób. W pracy poświęcono uwagę ekstraktom z cytryny, imbiru, rożeńca górskiego, brzozy oraz mięty. Pomiaru ilości antyoksydantów dokonano z użyciem trzech metod: Folina-Ciocalteu, DDPH i ABTS. Celem było oznaczenie zawartości antyoksydantów oraz porównanie wyżej wymienionych metod. Najgorsze właściwości antyoksydacyjne wykazała cytryna, natomiast najlepsze efekty posiadał korzeń różeńca górskiego.

EN

Nowadays, there is a growing interest in antioxidant compounds because of their biological activity – antioxidant capacity. Knowledge of the content of active substances in various products is extremely important in caring for one’s health and preventing disease. In this study, attention was paid to extracts from lemon, ginger, mountain ash, birch, and mint. Antioxidant amounts were measured using three methods: Folin-Ciocalteu, DDPH, and ABTS. The aim was to determine the antioxidant content and to compare the aforementioned methods. Lemon showed the worst antioxidant properties, while Rhodiola rosea root had the best results.

2

Investigation of the Antioxidant and Anti-Inflammatory Capacities of Different Extracts from Cistus ladanifer L. Leaves in the Ait Ammart Region (Northern Morocco)

Benamari Omar, Labhar Amina, Ahidar Naoufal, Salhi Amin, Ahari M’hamed, Elyoussfi Abdellah, Benyoub Bouchra, Amhamdi Hassan

Ecological Engineering & Environmental Technology

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2024

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Vol. 25, iss. 3

178--184

EN

Plants are a significant source for identifying new compounds (particularly secondary metabolites) with medicinal value for drug development, pharmaceuticals, and food additives. Many of these healing plants are frequently used in conventional medicine to treat and prevent various diseases. The purpose of the current research is to assess the total phenolic content (TPC) and total flavonoid content (TFC) for phytochemical analysis, DPPH and FRAP (Ferric Reducing Antioxidant Power) assays for antioxidant activity (AOA), and the activity of reducing inflammation exhibited by various extracts, which were determined by measurement of absorbance with a UV spectrophotometer. The outcome demonstrated that the Cistus ladanifer L leaf aqueous extract (EAqCL) has the highest yield (15.581%) and the highest phenolic content (98.28 ± 0.32 mg GAE/gext) compared to the other extracts. Whereas, ethanol extract (EECL) exhibited the highest flavonoid content (11.39 ± 1.45 mg QE/gext), DPPH-radical scavenging activity (RSA = 94.534 ± 1.24%) at 800 μg/ml and FRAP (1.017 ± 0.12) at 400 μg/mL. The extract also showed better anti-inflammatory activity (95.61 ± 0.92%) at 1000 μg/ml. According to the results obtained, this sticky shrub growing in the Ait Ammart region has great potential for exploiting natural sources of bioactive substances and producing pharmacologically active metabolites.

3

Antioxidant radical scavenging capacity and total carotenoid content of narrow-clawed crayfish (Pontastacus leptodactylus, Eschscholtz, 1823) in Atikhisar Reservoir (Çanakkale, Türkiye)

Acarlı Sefa, Kızılkaya Bayram, Vural Pervin, Barber Selçuk, Kale Semih, Acarlı Deniz

Oceanological and Hydrobiological Studies

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2023

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Vol. 52, No. 4

471--483

EN

n this study, antioxidant radical scavenging capacity and total carotenoid content in the meat and shells of Pontastacus leptodactylus were investigated. Concerning the antioxidant scavenging effect, the highest IC50 values were found to be 388.77 mg g-1 and 155.53 mg g-1 for females and males in July and March, respectively. The mean IC50 values of the meat were calculated as 239.83 mg g-1 and 105.21 mg g-1 for females and males, respectively. The mean total carotenoid content in the meat was found to be 14.35 and 12.78 μg g-1 for females and males, respectively. The results indicated that crayfish meat had antioxidant radical scavenging capacity and was rich in carotenoid content.

4

First Report of in Vitro Biological Agent to Biocontrol of Date Palm Stipe Rot Affected by Fusarium brachygibbosum by Using Pergularia tomentosa L., Aqueous Extract

Baba Mohamed Lemine, Essghaier Badiaa, Robledo-Mahón Tatiana, Abidine Mohamed Mahmoud, Aranda Elisabet, Sánchez José, Elemine Brahim Ould, Gallego Eduardo, Sebai Khaled, Vadel Ahmedou

Journal of Ecological Engineering

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2023

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Vol. 24, nr 9

373--384

EN

Palm (Phoenix dactylifera L.) is a specie cultivated in Mauritania. The present study is focused on the potential of the aqueous extract of the Pergularia tomentosa L., as biological control agent against Fusarium brachygibbosum, the main agent of the date palm stipe rot disease in Mauritania. Fungal pathogen was isolated from symptomatic date palm stipe rot disease in Mauritania. The morphological characterization and the molecular identification by sequencing ITS1, ITS2 5.8 RNAr region showed homology of 98% with Fusarium brachygibbosum strain UOA/HCPF 16982 s during in vitro tests on leaves performed to verify its phytopathogenicity. The inhibitory effect of aqueous extract of Pergularia tomentosa L. on the phytopathogenic isolate (Fusarium brachygibbosum) of date palm, on mycelial growth and spore germination was observed. In fact, in vitro on PDA, mycelial growth ranged from 39.23 to 67.7%, depending on the concentration of the aqueous extract of P. tomentosa. The aqueous extract showed a reduction of spore germination varying from 5.3 to 23.8%. The minimum inhibitory concentrations varied from 1 to 100 mg/ml. The various extracts give high antioxidant activities exhibited by DPPH assay. Multivariant analysis by PCA plot and the heatmap were done, to evaluate the correlation between the tested parameters. These results suggest the use of Pergularia tomentosa L., extract as a biological agent to control and reduce damage caused by Fusarium brachygibbosum.

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Facile green synthesis of Cinnamomum tamala extract capped silver nanoparticles and its biological applications

Narath Sajina, Shankar S. Sharath, Sivan Saranya Kothaplamoottil, George Bini, Thomas T. Dennis, Sabarinath Sankarannair, Jayaprakash Sajithkumar K., Wacławek Stanisław, Padil Vinod V. T.

Ecological Chemistry and Engineering. S

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2023

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Vol. 30, nr 1

7--21

EN

The plant mediated biogenic synthesis of nanoparticles is of magnificent concern due to its eco-benign and single pot nature. Here, Cinnamomum tamala (C. tamala) aqueous leaf extract was utilised for the silver nanoparticles’ (Ag NPs) synthesis. The phytoconstituents in the leaf extract were analysed by standard methods. These metabolites, especially carbohydrate polymers reduce Ag ions to Ag NPs accompanied by a reddish-brown coloration of the reaction mixture. The visual observation of intense brown colour is the first indication of the formation of Ag NPs. Various spectro-analytical techniques further characterise the Ag NPs. The green synthesised spherical Ag NPs were crystalline with an average size of 38 nm. The Ag NPs were scrutinised for antioxidant, antimicrobial and cytotoxic activity and obtained good results. The free radical scavenging was studied by 2, 2-Diphenyl-l-picrylhydrazyl (DPPH) assay. The antibacterial activity of Ag NPs was assessed against human pathogens, and it shown to have good antibacterial potency against a wide spectrum of bacteria. The cytotoxic activity against HEK-293T (human embryonic kidney) cell line was evaluated by 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) assay. These potent biological activities enable C. tamala capped Ag NPs to be suitable candidates for the future applications in various fields, predominantly clinical and biomedical.

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Antioxidative properties of autumn olive (Elaeagnus umbellata) fruits according to the method of fruit preservation and solvent used in extraction

Zglińska Klara, Rygało-Galewska Anna, Niemiec Tomasz

Polish Technical Review

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2022

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No. 1

19--23

EN

Fruits of autumn olive (Elaeagnus umbellata) are the abundant source of antioxidative substances such as carotenoids, polyphenols, flavonoids, fat-soluble vitamins and Vitamin C. The conducted study was aimed at the selection of the optimum method for extraction of berries. To this end, two methods for preservation of the berries were compared: drying at 60°C and freeze-drying (lyophilisation) and two types of solvent, employed in the extraction: water and methanol. The results showed that the methanol extracts produced from lyophilized fruits were characterized by the highest antioxidative activity.

PL

Owoce oliwnika baldaszkowatego (łac. Elaeagnus umbellata, ang. Autumn olive) są bogatym źródłem substancji antyoksydacyjnych, takich jak karotenoidy, polifenole, flawonoidy, witaminy rozpuszczalne w tłuszczach oraz witamina C. Przeprowadzone badanie miało na celu wybranie optymalnej metody ekstrakcji jagód. W tym celu porównano dwie metody utrwalania owoców: suszenie w 60°C i liofilizację oraz dwa rodzaje rozpuszczalników użytych do ekstrakcji: wodę i metanol. Wyniki wykazały, że najwyższą aktywnością antyoksydacyjną charakteryzowały się ekstrakty metanolowe wykonane z owoców liofilizowanych.

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Exogenous regulation of the potatoes’ adaptive potential when using bio stimulants

Shitikova Aleksandra V., Abiala Adewale A., Tevchenkov Alexander A., Bazhenova Svetlana S., Lazarev Nikolay N., Kurenkova Evgeniya M.

Journal of Water and Land Development

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2022

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no. 54

234--238

EN

Potato from the Solanaceae family is one of the most important crops in the world and its cultivation is common in many places. The average yield of this crop is 20 Mg·ha-1 and it is compatible with climatic conditions in many parts of the world. The experiment studied the possibility of exogenous regulation of the adaptive potential available for four potato cultivars through the use of growth stimulants with different action mechanisms: 24-epibrassinolide (EBL) and chitosan biopolymer (CHT). The results allowed us to establish significant differences in growth parameters, plant height, leaf index, vegetation index, chlorophyll content, and yield structure. Monitoring growth and predicting yields well before harvest are essential to effectively managing potato productivity. Studies have confirmed the empirical relationship between the normalised difference vegetation index (NDVI) and N-tester vegetation index data at various stages of potato growth with yield data. Statistical linear regression models were used to develop an empirical relationship between the NDVI and N-tester data and yield at different stages of crop growth. The equations have a maximum determination coefficient (R2) of 0.63 for the N-tester and 0.74 for the NDVI during the flowering phase (BBCH1 65). NDVI and N-tester vegetation index positively correlated with yield data at all growth stages.

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Effect of oggtt on physicochemical properties, antioxidant activity and volatile compounds of noodles

Bahgaat Wafaa K., Ibrahim Gamil E., Hussein Ahmed M. S.

Biotechnology and Food Science

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2022

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Vol. 84, nr 1

3--18

EN

The present investigation aimed to evaluate the effect of noodles supplementation with oggtt at (5,10,15 and 20%) on physicochemical properties, antioxidant activity as well as volatile compounds. The cooked noodles evaluation based on cooking quality like volume and cooking loss as well as colour changes. An increase in protein, fat and ash was observed with the increase of oggtt supplementation level in noodles. The whole wheat flour had the highest value of total phenolic (462.3 μg GAE g−1) compared to oggtt and all fortified noodles without cooking and after cooking. The fortification levels of 5 and 10% did not affect significantly on colour and overall acceptability of noodles. The panelists scores recommended the usage levels of 5 and 10% of oggtt noodles which did not changed significantly in comparison with control sample. The evaluation of oggtt incorporation in noodles volatile compounds performer using HS-GC/MS analysis. Thirty volatile compounds in cooked noodles after fortification with oggtt had identified. The main volatile compound herein was 2-pentyl furan, which represent 44.12, 20.14 and 18.75% in cooked control and fortified noodles with oggtt at 5 and 10% respectively.

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Variation in radical antioxidant capacity and the total amount of carotenoids in razor clams, Ensis marginatus (Pennant, 1777), from the Çanakkale Strait (Abidealtı), Turkey

Kizilkaya Bayram, Acarli Sefa, Ertuğrul Pervin Vural, Berber Selçuk, Çelik Pinar

Oceanological and Hydrobiological Studies

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2021

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Vol. 50, No. 1

16--23

EN

Metabolic activities such as breathing and digestion, resulting from natural functions of the body through oxidation, lead to the formation of free radicals that cause cancer, premature cardiac aging and some chronic diseases. Antioxidants are substances that remove free radicals and prevent cell damage. Seafood significantly contributes to the elimination of free radicals, especially owing to its high quality nutrient content. In this context, the objective of the study was to determine the radical antioxidant capacity and the total amount of carotenes in razor clams. The IC50 (mg g−1) value of the DPPH radical sweeping effect varied over the months (p < 0.05), showing the highest value in June, gradually decreasing from September and reaching the lowest level in February. The total amount of carotenoids also varied, with the highest value in September (p < 0.05). The total amount of chlorophyll ranged from 6.15 µg g−1 in August to 66.71 µg g−1 in December.

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Stabilność termooksydacyjna smarów plastycznych

Skibińska Agnieszka

Nafta-Gaz

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2021

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R. 77, nr 7

471--479

PL

Niniejszy artykuł przeglądowy dotyczy szczególnej właściwości smarów plastycznych – odporności na utlenianie. Właściwość ta, określana również jako stabilność oksydacyjna lub termooksydacyjna, ma decydujący wpływ na jakość i długość czasu pracy smarów w węzłach tarcia, łożyskach i układach smarowania. Smary plastyczne stanowią układy koloidalne, w których zagęszczacz tworzy elastyczną przestrzenną sieć, utrzymując fazę ciekłą. Przedstawiono budowę smarów plastycznych, podział smarów na rodzaje w zależności od wykorzystywanego zagęszczacza. Opisano podstawowe dodatki występujące w smarach, a szczegółowo omówiono grupę stosowanych dodatków antyutleniających. W warunkach eksploatacji smar podlega działaniu szeregu czynników, które powodują jego niszczenie, takim jak: naprężenia ścinające, ciśnienie, obciążenia, zmienne warunki pracy, szczególnie zmiany temperatury. Przedstawiono rodzaje degradacji smarów, a także metody i techniki oceny procesów starzenia. Podczas eksploatacji smar, spełniając w układzie smarowania swoje podstawowe funkcje, narażony jest przede wszystkim na działanie wysokiej temperatury. Dominującym procesem starzenia, bezpośrednio wpływającym na okres użytkowania smaru, jest utlenianie. Omówiono proces utleniania z wyszczególnieniem czterech jego etapów: inicjacji, propagacji, rozgałęzienia łańcucha oraz terminacji. Jedną z metod zapobiegania procesowi utleniania jest dobór odpowiednich dodatków uszlachetniających. Stabilność termooksydacyjna smarów plastycznych może być modyfikowana poprzez wprowadzenie odpowiednich przeciwutleniaczy, których dobór zależy od rodzaju zagęszczacza smaru plastycznego oraz temperatury pracy smaru. Zamieszczony przegląd literatury z ponad dziesięciu ostatnich lat wskazuje, jak różnorodne są sposoby modyfikacji stabilności termooksydacyjnej smarów i metody oceny tej właściwości.

EN

This review article deals with a particular property of lubricating greases – resistance to oxidation. This property, also referred to as oxidative or thermal oxidation stability, has a decisive influence on the quality and duration of lubricating greases service life in friction nodes, bearings and lubrication systems. Lubricating greases are colloidal systems in which the thickener creates an elastic three-dimensional network, maintaining the liquid phase. The structure of lubricating greases, division of greases into types, depending on the thickener used, is presented. The basic additives in lubricating greases are described, and the group of used antioxidant additives is discussed in detail. Under operating conditions, the grease is subject to factors that cause its destruction – shear stress, pressure, loads, changing operating conditions, especially temperature changes. The types of lubricating greases degradation are presented, as well as methods and techniques of aging processes evaluation. During operation, the grease fulfilling its basic functions in the lubrication system is primarily exposed to high temperatures. The predominant aging process which directly affects the service life of the grease is oxidation. The oxidation process is discussed, with the specification of its four stages: initiation, propagation, chain branching and termination. One of the methods of preventing the oxidation process is the selection of appropriate improvers. Thermal oxidation stability of greases can be modified by introducing appropriate antioxidants, the selection of which depends on the type of grease thickener and the operating temperature of the grease. The published literature review from over the last ten years shows how diverse are the ways of modifying thermal oxidation stability of greases and the methods of assessing this property.

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Evaluation of antioxidation properties of natural polyphenol water extracts from selected plants in a model system

Telichowska Aleksandra, Kucharska Aleksandra, Kobus-Cisowska Joanna, Betka Marta, Szulc Piotr, Stachowiak Barbara

Journal of Research and Applications in Agricultural Engineering

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2021

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Vol. 66, nr 1

25--29

EN

In the recent times plants are becoming more popular. Their beneficial pro-health properties result from the content of numerous characteristic compounds. Reports are confirming their beneficial antioxidant, antibacterial and anti-inflammatory properties. The aim of this study was to compare the antioxidant potential and the characteristics of water extracts obtained from plants: yarrow herb (AM) (Achillea millefolium L.), knotweed herb (PA) (Polygonum aviculare L.), horsetail herb (EA) (Equisetum arvense L.), and motherwort herb (LC) (Leonurus cardiaca L.). Extracts osmolality was from 0,142a±0.02 mOsm/kg H2O for the AM extract to 0,176c±0,01 mOsm/kg H2O for the EA extract. The test with the use of the Folin-Ciocalteu reagent showed that the EA extract had the highest content of reducing compounds (54,24d±2,19 mg GAE/g dw). It was shown that the highest activity against the DPPH radical was obtained for the extract from Equisetum arvense L. (5.97c±0.11 mg TE/1 g dw), and this extract also showed the highest antioxidant capacity measured with the radical ABTS method (7.23b±0.06 mg TE/g dw). These analyses were also confirmed by the tests carried out using the FRAP test, EA extract also showed 40% higher activity compared to the lowest AM extract. It has been shown that the investigated herbal raw materials can be an attractive raw material with antioxidant properties that can be used in application in food technology.

PL

Surowce roślinne cieszą się coraz większą popularnością. Ich korzystne właściwości prozdrowotne wynikają z zawartości licznych charakterystycznych związków. Dostępne są doniesienia, potwierdzające ich korzystne właściwości antyoksydacyjne, przeciwbakteryjne i przeciwzapalne. Celem niniejszej pracy było porównanie potencjału przeciwutleniającego oraz charakterystyka ekstraktów wodnych uzyskanych z następujących roślin: ziele krwawnika (AM) (Achillea millefolium L.), ziele rdestu ptasiego (PA) (Polygonum aviculare L.), ziele skrzypu (EA) (Equisetum arvense L.) oraz ziele serdecznika (LC) (Leonurus cardiaca L.). Osmolalność ekstraktów wynosiła od 0,142a±0,02 mOsm/kg H2O dla ekstraktu AM do 0,176c±0,01 mOsm/kg H2O dla ekstraktu EA. Test z odczynnikiem Folin-Ciocalteu wykazał, że ekstrakt EA charakteryzował się najwyższą zawartością związków redukujących (54,24d±2,19 mg GAE/g sm). Najwyższą aktywność wobec rodnika DPPH uzyskano dla ekstraktu z Equisetum arvense L. (5,97c±0,11 mg TE/1g sm), ekstrakt ten wykazał także najwyższą zdolność antyoksydacyjną mierzoną metodą z kationorodnikiem ABTS (7,23b±0,06 mg TE/g sm). Analizy te zostały również potwierdzone w teście z użyciem metody FRAP, ekstrakt EA wykazywał o 40% wyższą aktywność w porównaniu z najniższym uzyskanym wynikiem (AM). Wykazano, że badane surowce zielarskie mogą być atrakcyjnym źródłem związków polifenolowych o właściwościach przeciwutleniających, które mogą znaleźć znacznie szersze niż dotychczas zastosowanie w technologii żywności.

12

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.

13

Potential natural sources of tocopherols and tocotrienols and possibilities their use in the food industry®

Szewczyk Kacper

Postępy Techniki Przetwórstwa Spożywczego

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2020

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nr 1

139--147

EN

Tocopherols and tocotrienols are natural compounds found in oil plants. Their antioxidant properties make them interesting for food producers and consumers looking for healthy food. The aim of this study is to present the potential natural sources of tocopherols and tocotrienols, which as antioxidants are increasingly used as food additives to extend itheir durability, and additionally enrich the product with vitamin E. The work shows their chemical structure, methods of obtaining and legal regulations allowing tocopherols and tocotrienols for use in food processing. The current ways of using them in food production were discussed.

PL

Tokoferole i tokotrienole to naturalne związkami występują-ce w roślinach oleistych. Ich właściwości przeciwutleniają-ce sprawiają, że są interesujące dla producentów żywności i konsumentów poszukujących zdrowej żywności. Celem arty-kułu jest omówienie potencjalnych naturalnych źródeł toko-feroli i tokotrienoli, które jako substancje przeciwutleniające są coraz częściej wykorzystywane jako dodatki do żywności w celu przedłużenia jej trwałości, a dodatkowo wzbogacają produkt w witaminę E. W artkule przedstawiono ich struktu-rę chemiczną, sposoby pozyskiwania oraz regulacje prawne dopuszczające tokoferole i tokotrienole do wykorzystania w przetwórstwie żywności. Omówiono dotychczasowe sposo-by ich wykorzystania w produkcji żywności.

14

Effect of silymarin on thermooxidative degradation of PLA/PHB blends

Olejnik Olga, Masek Anna

Inżynieria Materiałowa

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2020

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Vol. 41, nr 3

7--11

EN

The effect of antioxidant of natural origin, i.e. silimarine on mechanical properties and thermooxidative degradation of biodegradable polylactide and polyhydroxybutyrate (PLA/PHB) blends obtained by melt mixing in a single-screw extruder (D = 25 mm, L/D = 24) was investigated. The addition of silymarin (0.7, 1.4 and 2.1 wt. %) improves the resistance to thermooxidative degradation of PLA/PHB blends, as evidenced by the value of the aging coefﬁ cient. Moreover, thanks to its unique properties, silymarin has a stabilizing effect and can be used as a pigment for polymers.

PL

Zbadano wpływ przeciwutleniacza pochodzenia naturalnego, tj. sylimaryny na właściwości mechaniczne oraz degradację termooksydacyjną biodegradowalnych mieszanin polilaktydu i polihydroksymaślanu (PLA/PHB). Mieszaniny otrzymano metodą mieszania w stanie stopionym przy użyciu wytłaczarki jednoślimakowej (D = 25 mm, L/D = 24). Dodatek (0,7; 1,4; 2,1% mas.) sylimariny poprawia odporność na degradację termooksydacyjną mieszanin PLA/PHB, o czym świadczy wartość współczynnika starzenia. Ponadto dzięki swoim wyjątkowym właściwościom sylimaryna ma działanie stabilizujące i może być stosowana jako barwnik do polimerów.

15

Comparison of the Antimicrobial and Antioxidant Efficacy of Viscose Treated with Various Natural Compounds for Medical Use

Šauperl Olivera, Tompa Jasna

Fibres & Textiles in Eastern Europe

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2020

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Vol. 28, no. 6 (144)

85--88

EN

This research is based on the use of a variety of natural compounds and their mixtures with chitosan in order to create an efficient textile product for sanitary/medical use which shows antimicrobial and antioxidant effectiveness at the same time. It is assumed that natural compounds showing antimicrobial and antioxidant efficacy also do so even when applied on a non-woven viscose substrate intended for wound healing. A study of the effectiveness of the individual treatment was performed using antimicrobial (dynamic-stress test) and anti-oxidative (ABTS•+) testing. It was confirmed that the properties of functionalised viscose treated with different functionalisation formulations differ in dependence on the separate formulations. Results show that for a comprehensive insight into the antimicrobial and antioxidant activity of functionalised viscose, a very detailed study of the results of antimicrobial and antioxidant testing is needed in order for it to be possible to create a textile material with the necessary functionality.

PL

Zaprezentowane badania opierały się na wykorzystaniu różnorodnych związków naturalnych i ich mieszanin z chitozanem w celu stworzenia wydajnego wyrobu tekstylnego do użytku sanitarno-medycznego, wykazującego jednocześnie skuteczność przeciwbakteryjną i antyoksydacyjną. Zakłada się, że naturalne związki wykazują skuteczność przeciwbakteryjną i przeciwutleniającą również po nałożeniu na podłoże z włókniny wiskozowej przeznaczonej do procesu gojenia ran. Badanie skuteczności leczenia indywidualnego przeprowadzono za pomocą testów przeciwbakteryjnych (test obciążenia dynamicznego) i antyoksydacyjnych (ABTS•+). Potwierdzono, że właściwości funkcjonalizowanej wiskozy poddanej działaniu różnych formulacji funkcjonalizujących różnią się w zależności od poszczególnych formulacji. Wyniki pokazały, że aby uzyskać kompleksowy wgląd w działanie przeciwbakteryjne i przeciwutleniające funkcjonalizowanej wiskozy, potrzebne jest bardzo szczegółowe badanie wyników testów przeciwbakteryjnych i przeciwutleniających, tak aby możliwe było stworzenie materiału tekstylnego o niezbędnej funkcjonalności.

16

Witamina C w medycynie i kosmetologii

Musiał Claudia, Sawczuk Wojciech, Gawdzik Barbara, Kuban-Jankowska Alicja, Przychodzeń Paulina, Górska-Ponikowska Magdalena

Wiadomości Chemiczne

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2019

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[Z] 73, 9-10

503--522

EN

Ascorbic acid is one of the strongest antioxidants. It has a protective function against oxidative stress intracellularly. It fights free radicals and eliminates the effects of ultraviolet radiation. The human body is unable to synthesize vitamin C itself. Vitamin C meets supports the mechanism of removing toxins from the human body and has anticancer activity. Over the years, many studies have been carried out to confirm the beneficial effect of preventive and supportive action of cytostatics in the treatment of cancer. Clinical studies described in the study indicate that vitamin C used in combination with a cytostatic drug - gemcystabine, shows no side effects. Vitamin C applied topically on the skin shows a number of positive effects. Studies have shown that vitamin C accumulates in the deeper layers of the skin for about three days. Ascorbic acid has a protective effect against harmful ultraviolet radiation. Manufacturers of cosmetics often add ascorbic acid to cosmetics with sunscreens. In addition, vitamin C acts depigmenting. In order to increase the brightening effect, vitamin C is often combined with glycolic acid or retinol. Ascorbic acid is also used in anti-aging preparations due to the high ability of collagen synthesis in the skin. In topical preparations, ascorbic acid has hydrophilic properties - it is soluble in water and insoluble in fats. Hydrophilic ascorbic acid in synergy with lipophilic tocopherol reduces cell apoptosis and thymine dimer formation. Its stability improves the presence of stabilizing antioxidants, such as vitamin E and ferulic acid. For the preparation to retain its properties, it should be protected from light and oxygen. The development of biotechnology allows the closure of a micronised vitamin C in nanosomes and liposomes, which increases the ability to penetrate deep into the skin. A number of vitamin C derivatives such as ascorbyl tetrapalmitate and ascorbyl phosphate magnesium help achieve the desired results in topical application.

17

Efektywność działania środków przeciwstarzeniowych w procesie przyśpieszonego starzenia cieplnego

Kasprzyk Paulina, Bartkowski Daniel, Włoch Marcin, Datta Janusz

Elastomery

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2019

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T. 23, nr 2

112--122

PL

Przedmiotem przedstawionych badań są wulkanizaty kauczuku naturalnego i butadienowo-styrenowego. Celem pracy było zbadanie efektywności działania środków przeciwstarzeniowych w procesie przyspieszonego starzenia cieplnego (w czasie 7 i 14 dni w temperaturze 70°C). Do badań wykorzystano dwie substancje przeciwstarzeniowe: komercyjnie dostępny przeciwutleniacz IPPD (N–fenylo-N′-izopropylo-p-fenylenodiamina) oraz ekologiczny przeciwutleniacz K (aminowo-amidowa pochodna kalafonii). Struktura chemiczna próbek referencyjnych oraz wulkanizatów po procesie starzenia została zidentyfikowana z wykorzystaniem analizy spektroskopowej w podczerwieni (FTIR). Zbadano również właściwości mechaniczne wulkanizatów przy statycznym rozciąganiu, twardość, elastyczność przy odbiciu oraz ścieralność. Przeprowadzone badania dowiodły wysokiej efektywności działania przeciwutleniacza K, szczególnie w przypadku wulkanizatów opartych na kauczuku naturalnym.

EN

The subject of the presented research are vulcanizates of natural rubber and styrene-butadiene rubber. The aim of the work was to examine the effectiveness of anti-aging agents in the process of accelerated heat aging (during 7 and 14 days at 70°C) . Two anti-aging substances were used for the study: the commercially available IPPD antioxidant (N-phenyl-N′-isopropyl-p-phenylenediamine) and the eco-friendly K antioxidant (amino-amide derivative of rosin). The chemical structure of reference samples and vulcanizates after the aging process was identified using FTIR spectroscopy. The selected mechanical properties were also characterized: hardness, impact resilience, abrasiveness and properties in a static tensile test. The studies have proved the high effectiveness of K antioxidant, especially for vulcanizates based on natural rubber.

18

Antiradical properties of chemo drug, carboplatin, in cooperation with ZnO nanoparticles under UV irradiation in putative model of cancer cells

Pairoj Suttirak, Damrongsak Pattareeya, Damrongsak Badin, Jinawath Natini, Kaewkhaw Rossukon, Leelawattananon Tanaporn, Ruttanasirawit Chinnapat, Locharoenrat Kitsakorn

Biocybernetics and Biomedical Engineering

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2019

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Vol. 39, no. 3

893--901

EN

The main objective of this study was to assess the antiradical properties of zinc oxide (ZnO) nanoparticles upon exposure to ultraviolet radiation with carboplatin, an anti-proliferative drug used in the treatment of retinoblastoma. For the purpose of this study, the decomposition of 2,2(diphenyl-1-picryhydrazyl) radical (DPPH*) was used to assess the free radical capacity of antioxidants and was followed by MTT measurements. To test the antiradical capacity, the effective concentration, antiradical power, stoichiometry, and number of reduced DPPH* were investigated. DPPH* has a peak absorbance at a wavelength of 515 nm, which disappears upon the introduction of the antiradical agents. Four agents were reacted with DPPH* and represented the possible reaction kinetic categories. ZnO nanoparticles and carboplatin-loaded ZnO nanoparticles reacted more strongly with DPPH* and approached a saturation state at 420 min. The remaining two antiradical agents, ZnO nanoparticles under UV radiation and carboplatin-loaded ZnO nanoparticles under UV radiation, reacted a bit slower with DPPH* and approached a steady state at 1440 min. Among the different four antiradical agents, carboplatin-loaded ZnO nanoparticles under UV light had the highest antiradical response with the lowest effective concentration value to the reduced DPPH* molecules. ZnO nanoparticles alone were found to be poor antiradical agent. Possible mechanisms were attributed to the number of hydroxyl groups available to decrease the number of DPPH*.

19

Some bioactive properties of Acacia dealbata extracts and their potential utilization in wood protection

Yildiz S., Gürgen A., Can Z., Tabbouche S. A., Kiliç A. O.

Drewno : prace naukowe, doniesienia, komunikaty

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2018

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vol. 61, nr 202

81--97

EN

A study was made of the potential use of Acacia dealbata wood extracts as bioprotective agents. Initially, extracts were obtained from Acacia dealbata sapwood, heartwood and bark, and their antioxidant, antimicrobial and anti-quorum sensing activities were determined. Next, the decay resistance of Scots pine wood samples impregnated with these extracts was examined against the brown rot fungus, Coniophora puteana. The impregnation procedure was performed according to the ASTM D (1413) standard test method at two different concentrations, 3% and 5% by weight, using hot water and methanol as extraction solvents. The strongest antioxidant, antimicrobial and anti-quorum sensing activities were those of the bark extract. Hot water extraction led to lower performance than methanol extraction. According to EN 113 testing methods, the highest level of preservative effect against wood-decaying fungi was observed in the case of 5% methanol extract from the bark.

20

Target-guided isolation and purification of antioxidants from Elsholtzia densa benth. var. densa by DPPH antioxidant assay and dual-mode HSCCC

Zhou W. N., Ouyang J., Wang Z. H., Wang X. Y., Suo Y. R., Zhang Z., Wang H. L.

Acta Chromatographica

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2018

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Vol. 30, no. 3

180--185

EN

Elsholtzia densa Benth. var. densa (Lamiaceae) is a famous medicinal herb which has been widely used for treatment of colds, headaches, pharyngitis, fever, diarrhea, digestion disorder, rheumatic arthritis, nephritises, and nyctalopia in China. In this study, fraction of the ethyl alcohol extract of E. densa (aerial part) by different polarity solvents indicated that the ethyl acetate soluble fraction exhibited a potent 1,1-diphenyl-2-picryhydrazyl (DPPH) radical scavenging activity with the IC50 value of 148.2 μg/mL. Under the target guidance of DPPH experiment, isoquercitrin, trachelogenin, ethyl caffeate, and arctigenin were separated with purities 95.98%, 92.98%, 96.07%, and 88.83%, respectively, by a dual-mode high-speed counter-current chromatography (HSCCC) method using n-hexane–ethyl acetate–methanol–water (4.5:5:3:4, v/v/v/v) as the solvent system. In order to evaluate the scientific basis, antioxidant activity of four isolated compounds was assessed by the radical scavenging effect on DPPH radical; isoquercitrin and ethyl caffeate showed stronger antioxidant activities with IC50 values of 9.4 μg/mL and 9.2 μg/mL, respectively, while trachelogenin and arctigenin showed weak antioxidant activities with IC50 values of >500 μg/mL and 72.8 μg/mL, respectively. Results of the present study indicated that the combinative method using DPPH antioxidant assay and dual-mode HSCCC could be widely applied for rapid screening and isolating of antioxidants from complex traditional Chinese medicine extract.