Effects of Isosorbide Incorporation into Flexible Polyurethane Foams: Reversible Urethane Linkages and Antioxidant Activity

Isosorbide (ISB), a nontoxic bio-based bicyclic diol composed from two fuzed furans, was incorporated into the preparation of flexible polyurethane foams (FPUFs) for use as a cell opener and to impart antioxidant properties to the resulting foam. A novel method for cell opening was designed based on the anticipated reversibility of the urethane linkages formed by ISB with isocyanate. FPUFs containing various amounts of ISB (up to 5 wt%) were successfully prepared without any noticeable deterioration in the appearance and physical properties of the resulting foams. The air permeability of these resulting FPUFs was increased and this could be further improved by thermal treatment at 160 °C. The urethane units based on ISB enabled cell window opening, as anticipated, through the reversible urethane linkage. The ISB-containing FPUFs also demonstrated better antioxidant activity by impeding discoloration. Thus, ISB, a nontoxic, bio-based diol, can be a valuable raw material (or additive) for eco-friendly FPUFs without seriously compromising the physical properties of these FPUFs.

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Antioxidant properties, quantification and stability of betalains from pitaya (Hylocereus undatus) peel

Ciência Rural ◽

10.1590/0103-8478cr20140548 ◽

2014 ◽

Vol 45 (2) ◽

pp. 323-328 ◽

Cited By ~ 12

Author(s):

Fernanda Robert de Mello ◽

Claudia Bernardo ◽

Caroline Odebrecht Dias ◽

Luciano Gonzaga ◽

Edna Regina Amante ◽

...

Keyword(s):

Antioxidant Activity ◽

Phenolic Compounds ◽

Antioxidant Properties ◽

Raw Material ◽

High Concentration ◽

Natural Colorant ◽

Wide Ph Range ◽

Hylocereus Undatus ◽

Ph Range ◽

Promising Source

Pitaya peel can be used as a raw material for betalains extraction. The aim of this research was to quantify phenolic compounds, antioxidant activity and betalains on pitaya peel. Furthermore, evaluate the betalains stability against various pH conditions and exposure time of heating. The results showed that pitaya peel contains phenolic compounds and presented antioxidant activity. Moreover it showed high concentration of betalains (101.04mg equivalent to betanin. 100g-1) which were stable over a wide pH range (3.2 - 7.0) and were resistant to heating (100oC) up to 10 minutes at pH range from 3.7 to 5.5. Therefore, pitaya peel is a promising source of betalains which can be applied as a natural colorant for food.

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Effects of raw material on the chemical composition, organoleptic properties, antioxidant activity, physical properties and the yield of instant black tea

LWT ◽

10.1016/j.lwt.2015.03.060 ◽

2015 ◽

Vol 63 (1) ◽

pp. 745-750 ◽

Cited By ~ 7

Author(s):

Gardhi Arachchilage Aruna Ranjith Perera ◽

Amarakoon Mudiyanselage Tissa Amarakoon ◽

Dona Chamara Kumari Illeperuma ◽

Palavinnage Krishantha Pushpakumara Muthukumarana

Keyword(s):

Antioxidant Activity ◽

Chemical Composition ◽

Physical Properties ◽

Black Tea ◽

Raw Material ◽

Organoleptic Properties

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Comparing the effect of carbon-based nanofillers on the physical properties of flexible polyurethane foams

Journal of Materials Science ◽

10.1007/s10853-012-6331-4 ◽

2012 ◽

Vol 47 (15) ◽

pp. 5673-5679 ◽

Cited By ~ 41

Author(s):

M. Mar Bernal ◽

Isabel Molenberg ◽

Sergio Estravis ◽

Miguel Angel Rodriguez-Perez ◽

Isabelle Huynen ◽

...

Keyword(s):

Physical Properties ◽

Polyurethane Foams ◽

Flexible Polyurethane ◽

Carbon Based

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Chemical compounds contained in young and mature leaves of agarwood species Wikstroemia tenuiramis and its antioxidant properties

Biodiversitas Journal of Biological Diversity ◽

10.13057/biodiv/d211020 ◽

2020 ◽

Vol 21 (10) ◽

Author(s):

RIDWANTI BATUBARA ◽

TENGKU ISMANELLY HANUM ◽

ODING AFFANDI ◽

HENNY SRI WAHYUNI

Keyword(s):

Antioxidant Activity ◽

Antioxidant Properties ◽

Chemical Compounds ◽

Raw Material ◽

Gas Chromatography Mass Spectrometry ◽

Phytochemical Analysis ◽

Mature Leaves ◽

Dpph Method ◽

North Sumatra ◽

Chemical Contents

Abstract. Batubara R, Hanum TI, Affandi O, Wahyuni HS. 2020. Chemical compounds contained in young and mature leaves of agarwood species Wikstroemia tenuiramis and its antioxidant properties. Biodiversitas 21: 4616-4622. The genus Wikstroemia is one of the genus of agarwood producing trees which has not been widely researched and published. One type of this genus is Wikstroemia tenuiramis Miq, which grows naturally in North Sumatra, the leaves are like other types of agarwood leaves can be used as raw material for agarwood leaves tea. A research has been conducted to determine the chemical contents contained in the young and mature leaves of agarwood plants species W. Tenuiramis. This research methods applied qualitative analysis using phytochemical screening, quantitative analysis to determine tannin content using titration method, antioxidant activity analysis using 2,2-diphenil-1-picrylhydrazil (DPPH) method, and compound tracing using Py-gas chromatography-mass spectrometry (Py-GC-MS) instruments. The qualitative phytochemical analysis results showed no difference in chemical compounds contained in both the young and mature leaves. Both the young and mature leaves contained flavonoids, triterpenoids, and tannins, and did not contain alkaloids, steroids and saponins. The young contained tannins of 1.079 ± 0.001% and the mature contained tannins of 4.645 ± 0.021%, not significant statistically. Py-GC-MS analysis showed the presence of various 30 bioactive compounds contained in both young and mature leaves. The analysis results also showed that both the young and mature leaves had very strong antioxidant activity. Our findings suggest that the two types of leaves have equal utility value of in term of chemical contents and antioxidant potentials.

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Antioxidant and Antiglycation Properties of Seventeen Fruit Teas Obtained from One Manufacturer

Applied Sciences ◽

10.3390/app10155195 ◽

2020 ◽

Vol 10 (15) ◽

pp. 5195 ◽

Cited By ~ 1

Author(s):

Izabela Zieniewska ◽

Anna Zalewska ◽

Małgorzata Żendzian-Piotrowska ◽

Jerzy Robert Ładny ◽

Mateusz Maciejczyk

Keyword(s):

Antioxidant Activity ◽

Antioxidant Properties ◽

Aromatic Amino Acids ◽

Raw Material ◽

Quantitative Composition ◽

Production Location ◽

Dried Fruit ◽

Health Promoting ◽

High Antioxidant Activity

The antioxidant activity of teas depends on the type and quality of the ingredients used in the process of tea production, location of the crops, and manner of the raw material processing. Our study is the first to compare the antioxidant and antiglycation properties of seventeen fruit teas obtained from one manufacturer. We evaluated three different brewing times (3, 5, and 10 min) and two brewing temperatures (70 and 100 °C). We demonstrated that infusions with the longest brewing time reveal the highest antiradical activity, while increased brewing temperature does not significantly affect the assessed parameters. The best antioxidant properties were obtained for the teas made from lemon balm with pear, forest fruits, cranberry with pomegranate, raspberry, and raspberry with linden. Fruit teas owe their high antioxidant activity to the presence of polyphenolic compounds in infusions. Extracts from fruit teas also diminish the oxidation and glycation of albumin in vitro, observed as a decrease in the fluorescence of aromatic amino acids and advanced glycation (AGE) and oxidation (AOPP) protein products levels. In conclusion, in order to prepare fruit teas with the best antioxidant properties, a longer extraction time is needed. The health-promoting properties of dried fruit infusions can be modified by changing the qualitative and quantitative composition of the ingredients.

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Enhanced flame-retardancy and controlled physical properties of flexible polyurethane foams based on a shear-responsive internal network

RSC Advances ◽

10.1039/c7ra07083g ◽

2017 ◽

Vol 7 (69) ◽

pp. 44013-44020 ◽

Cited By ~ 3

Author(s):

Jingyi Rao ◽

María P. Fernández-Ronco ◽

Michel Vong ◽

Sabyasachi Gaan

Keyword(s):

Physical Properties ◽

Flame Retardancy ◽

Polyurethane Foams ◽

Solid Polymer ◽

Interface Chemistry ◽

Polymer Interface ◽

Internal Network ◽

Flexible Polyurethane

The flame retardancy of FPUFs can be enhanced by the manipulation of the solid-polymer interface chemistry.

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Antioxidant activity of St. John’s Wort extracts obtained with ultrasound-assisted extraction

Pomeranian Journal of Life Sciences ◽

10.21164/pomjlifesci.640 ◽

2019 ◽

Vol 65 (4) ◽

Author(s):

Anna Muzykiewicz ◽

Katarzyna Florkowska ◽

Anna Nowak ◽

Joanna Zielonka-Brzezicka ◽

Adam Klimowicz

Keyword(s):

Antioxidant Activity ◽

Antioxidant Properties ◽

Raw Material ◽

Aqueous Extracts ◽

Ultrasound Assisted Extraction ◽

Antioxidant Power ◽

St John’S Wort ◽

St John's Wort ◽

Assisted Extraction ◽

Ultrasound Assisted

Introduction: St. John’s Wort (Hypericum perforatum L.) is a plant from the Hypericaceae family commonly occurring in Europe, Asia, Africa and North America. It is used for medical purposes, for example in depression, viral or bacterial diseases, as well as diseases of the digestive system. St. John’s Wort is a source of hypericin as well as flavonoids useful to reduce the harmful effects of free radical action.The aim of the study was to evaluate the antioxidant activity of alcoholic and aqueous extracts of H. perforatum.Materials and methods: St. John’s Wort extracts were prepared in ethanol, methanol and isopropanol (each of 40%, 70% (v/v) and undiluted) and in water, with ultrasound-assisted extraction. Plant samples were extracted for 15, 30 and 60 min, and the antioxidant potentials of the extracts evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) aand ferric reducing antioxidant power (FRAP).Results: All the extracts showed antioxidant activity. In the case of the DPPH evaluation, the results ranged 2.42–4.37 mg trolox/g of raw material, which corresponds to 53.89–91.98% radical scavenging activity (RSA). The highest results were obtained for samples extracted for 60 min, with the antioxidant activity of most of them above 4.00 mg trolox/g of raw material. In the case of FRAP evaluation, the reducing power of the extracts ranged 1.40–37.82 mg FeSO4/g of raw material, with the highest results found for samples prepared in undiluted methanol. In contrast, the antioxidant capacity of the aqueous extracts was low.Conclusions: St. John’s Wort herb showed high antioxidant activity. In most cases, higher potentials were found for the extracts prepared in undiluted alcohols. The type of solvent used and the extraction time influenced the antioxidant properties of the extracts.

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Physicochemical and antioxidant properties of banana varieties and sensorial evaluation of jelly prepared from those varieties available in Sylhet region

International Journal of Food Studies ◽

10.7455/ijfs.v7i2.546 ◽

2018 ◽

Vol 7 (2) ◽

Author(s):

Abdullah A. Sad ◽

M. M. Hoque ◽

Wahidu Zzaman

Keyword(s):

Antioxidant Activity ◽

Radical Scavenging Activity ◽

Antioxidant Properties ◽

Radical Scavenging ◽

Raw Material ◽

Banana Peel ◽

Total Phenolic ◽

Scavenging Activity ◽

Pharmaceutical Industries ◽

Sylhet Region

The present research aimed to evaluate and compare the antioxidant activity in both pulp and peel and the physicochemical contents in the pulp of four local varieties of banana, i.e. Musa acuminata species named Sagor, Champa, Shail and Bichi, available in Sylhet region of Bangladesh. The antioxidant activity from a methanolic extract of banana peels and pulps was evaluated by determination of total phenolic content and DPPH scavenging activity. The physicochemical contents of banana pulp such as protein, fat, moisture, ash and carbohydrate were also determined. The results showed that the overall antioxidant activity of banana peel was higher than the pulp of banana. The pulp of the Shail variety had the highest antioxidant activity (TPC = 80.14 mg GAE/100 g, DPPH radical scavenging activity =91.37%) among the four varieties. Fat (1.38%) and moisture (76.23%) contents were higher in the pulp of Shail, while protein (1.82%) and carbohydrate (22.71%) contents were higher in the pulp of Bichi. The Champa variety contained higher ash content (1.05%). Among the jellies prepared from those banana varieties, the jelly of the Shail variety showed the highest score for overall acceptance (6.8) whilst the jelly prepared from the Bichi variety showed the highest score for taste (7.75). This may be due to higher carbohydrate content. The study suggests that banana peel could be used in the food industry as a raw material to produce bakery products and in cosmetics and pharmaceutical industries as an antioxidant supplement.

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THE STUDY OF BEER QUALITY WITH THE REDUCED TOXIC EFFECT

EUREKA Life Sciences ◽

10.21303/2504-5695.2017.00303 ◽

2017 ◽

Vol 1 ◽

pp. 35-43 ◽

Cited By ~ 2

Author(s):

Nataliya Penkina ◽

Larisа Tatar ◽

Victoria Kolesnyk ◽

Tetiana Karbivnycha ◽

Tetiana Letuta

Keyword(s):

Antioxidant Activity ◽

Ascorbic Acid ◽

Pinus Sylvestris ◽

Toxic Effect ◽

Pathological Condition ◽

Antioxidant Properties ◽

Quality Parameters ◽

Raw Material ◽

Biological Objects ◽

The One

There was grounded the expedience of using unconventional vegetable raw material, namely Pinus sylvestris needle that partially replaced hop for beer enrichment. The optimal parameters of extraction of Pinus sylvestris needle relative to anti-oxidant activity of extract: hydromodulus 1:20, temperature 60 ºС, extraction 30 min. The needle extract has pure smell, harmonic refreshing taste with needle note. The content of ascorbic acid in extraction is 0,275 mg / 100 g, antioxidant activity – 202,3 C/100 g. The quantitative ratio of hop and pine needle in beer receipt was determined by the way of mathematical modeling. Quantitative content of Pinus sylvestris needle is no more than 20 % by mass from the rated norm of hop that is enough for preserving hop bitterness and smell. The receipt of beer, including Pinus sylvestris needle, was elaborated. The quality parameters of ready drink were studied. The addition of needle increases the beer gustatory properties, decreases methanol content. The content of ascorbic acid in ready drink is 3,52 mg/100 g. Antioxidant activity of elaborated beer is 178,1 C/100 g that determines its high biological value. The influence of beer with needle extract on antioxidant system of organism of biological objects was assessed. Under conditions of acute pathological condition the beer with needle extract decreases oxidative influence of drink on brain of biological objects. The beer “Smaragd” decreases toxic effect on organism of living creature due to its antioxidant properties. The introduction of needle extract that includes vegetable antioxidants in beer is the one of the ways to increase antioxidant capacity of ready drink. It opens the prospect of studies, directed on elaboration of arrangements of stabilization of different sorts of beer. The studies may be introduced in production that has positive effect on ready product quality.

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Bioactive Compounds, RP-HPLC Analysis of Phenolics, and Antioxidant Activity of Some Portuguese Shrub Species Extracts

Natural Product Communications ◽

10.1177/1934578x1100601219 ◽

2011 ◽

Vol 6 (12) ◽

pp. 1934578X1100601 ◽

Cited By ~ 6

Author(s):

Ângelo Luís ◽

Fernanda Domingues ◽

Ana Paula Duarte

Keyword(s):

Antioxidant Activity ◽

Phenolic Compounds ◽

Activity Index ◽

Colorimetric Method ◽

Antioxidant Properties ◽

Raw Material ◽

Total Phenolic ◽

Methanolic Extracts ◽

Rp Hplc

In the ecosystem of Serra Da Estrela, some plant species have the potential to be used as raw material for extraction of bioactive products. The goal of this work was to determine the phenolic, flavonoid, tannin and alkaloid contents of the methanolic extracts of some shrubs ( Echinospartum ibericum, Pterospartum tridentatum, Juniperus communis, Ruscus aculeatus, Rubus ulmifolius, Hakea sericea, Cytisus multiflorus, Crataegus monogyna, Erica arborea and Ipomoea acuminata), and then to correlate the phenolic compounds and flavonoids with the antioxidant activity of each extract. The Folin-Ciocalteu's method was used for the determination of total phenols, and tannins were then precipitated with polyvinylpolypyrrolidone (PVPP); a colorimetric method with aluminum chloride was used for the determination of flavonoids, and a Dragendorff's reagent method was used for total alkaloid estimation. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) and β-carotene bleaching tests were used to assess the antioxidant activity of extracts. The identification of phenolic compounds present in extracts was performed using RP-HPLC. A positive linear correlation between antioxidant activity index and total phenolic content of methanolic extracts was observed. The RP-HPLC procedure showed that the most common compounds were ferulic and ellagic acids and quercetin. Most of the studied shrubs have significant antioxidant properties that are probably due to the existence of phenolic compounds in the extracts. It is noteworthy to emphasize that for Echinospartum ibericum, Hakea sericea and Ipomoea acuminata, to the best of our knowledge, no phytochemical studies have been undertaken nor their use in traditional medicine been described.

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