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1.
Polymers (Basel) ; 14(24)2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36559918

RESUMO

The growing perspective of running out of crude oil followed by increasing prices for all crude oil-based materials, e.g., crude oil-based polymers, which have a huge number of practical applications but are usually neither biodegradable nor environmentally friendly, has resulted in searching for their substitutes-namely, bio-based polymers. Currently, both these types of polymers are used in practice worldwide. Owing to the advantages and disadvantages occurring among plastics with different origin, in this current review data on selected popular crude oil-based and bio-based polymers has been collected in order to compare their practical applications resulting from their composition, chemical structure, and related physical and chemical properties. The main goal is to compare polymers in pairs, which have the same or similar practical applications, regardless of different origin and composition. It has been proven that many crude oil-based polymers can be effectively replaced by bio-based polymers without significant loss of properties that ensure practical applications. Additionally, biopolymers have higher potential than crude oil-based polymers in many modern applications. It is concluded that the future of polymers will belong to bio-based rather than crude oil-based polymers.

2.
Molecules ; 27(18)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36144599

RESUMO

Over the last decades, we have witnessed an increasing interest in food-related products containing vegetable oils. These oils can be obtained either by extraction or by mechanical pressing of different parts of plants (e.g., seeds, fruit, and drupels). Producers of nutraceuticals have ceaselessly searched for unique and effective natural ingredients. The enormous success of argan oil has been followed by discoveries of other interesting vegetable oils (e.g., pomegranate oil) containing several bioactives. This work describes the pomegranate fruit extract and seed oil as a rich source of conjugated linolenic acid as a metabolite of punicic acid (PA), deriving from the omega-5 family (ω-5). Through the chemical characterization of PA, its nutritional and therapeutic properties are highlighted together with the physiological properties that encourage its use in human nutrition. We analyzed the composition of all fatty acids with beneficial properties occurring in pomegranate seed oil using gas chromatography (GC) with flame-ionization detection (FID) analysis combined with Fourier transform infrared spectroscopy (FTIR). Pomegranate seed oil mainly consists of 9,11,13-octadic-trienoic acid (18:3), corresponding to 73 wt % of the total fatty acids. Nine components were identified by GC in PSO, varying between 0.58 and 73.19 wt %. Using midinfrared (MIR) spectroscopy, we compared the composition of pomegranate seed oil with that of meadowfoam seed oil (MSO), which is also becoming increasingly popular in the food industry due to its high content of long chain fatty acids (C20-22), providing increased oil stability. From the results of FTIR and MIR spectroscopy, we found that punicic acid is unique in PSO (73.19 wt %) but not in MSO.


Assuntos
Lythraceae , Punica granatum , Cromatografia Gasosa , Ácidos Graxos/química , Humanos , Ácidos Linolênicos/química , Lythraceae/química , Extratos Vegetais/química , Óleos de Plantas/química , Sementes/química , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Biology (Basel) ; 9(10)2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33066555

RESUMO

As an immune-privileged target organ, the eyes have important superficial and internal barriers, protecting them from physical and chemical damage from exogenous and/or endogenous origins that would cause injury to visual acuity or even vision loss. These anatomic, physiological and histologic barriers are thus a challenge for drug access and entry into the eye. Novel therapeutic concepts are highly desirable for eye treatment. The design of an efficient ocular drug delivery system still remains a challenge. Although nanotechnology may offer the ability to detect and treat eye diseases, successful treatment approaches are still in demand. The growing interest in nanopharmaceuticals offers the opportunity to improve ophthalmic treatments. Besides their size, which needs to be critically monitored, nanopharmaceuticals for ophthalmic applications have to be produced under sterilized conditions. In this work, we have revised the different sterilization and depyrogenation methods for ophthalmic nanopharmaceuticals with their merits and drawbacks. The paper also describes clinical sterilization of drugs and the outcomes of inappropriate practices, while recent applications of nanopharmaceuticals for ocular drug delivery are also addressed.

4.
Acta Sci Pol Technol Aliment ; 14(4): 357-366, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-28068041

RESUMO

BACKGROUND: Canadian prairies are a habitat for unique wild plants. The main object of the present study was to investigate phytochemicals content and antioxidant activity in seven wild Canadian prairie fruits. METHODS: The presence of total phenolics, flavonoids, anthocyanins and antioxidant activity were identified in the extracts according to standard procedure. RESULTS: Wild rose had the highest amounts of total phenolics and total flavonoids, whereas elderberry exhibited the highest amount of anthocyanins. All extracts showed good scavenging activities towards DPPH radicals. The results showed a good linear relationship between oxygen radical absorbance capacity and total phenolics indicating that radicals are scavenged at a greater rate as the total phenolics content increases. Additionally, all extracts when applied at concentration of 800 ppm, showed ability to inhibit oxidation of canola oil. In SOT test the best results were obtained when extract of American mountain ash was used. In general, wild rose followed by American mountain ash demonstrated the highest antioxidant activity among assessed Canadian prairie fruits. CONCLUSIONS: From the results it can be concluded that prairie fruit extracts are a rich source of phenolic compounds and poses a high antioxidant activity, confirmed by assessment with different type of radicals employed.


Assuntos
Antioxidantes/isolamento & purificação , Elaeagnaceae/química , Frutas/química , Extratos Vegetais/isolamento & purificação , Rosaceae/química , Sambucus/química , Meio Selvagem , Alberta , Antocianinas/análise , Antioxidantes/química , Crataegus/química , Crataegus/crescimento & desenvolvimento , Gorduras Insaturadas na Dieta/análise , Elaeagnaceae/crescimento & desenvolvimento , Ácidos Graxos Monoinsaturados/química , Flavonoides/análise , Conservantes de Alimentos/química , Conservantes de Alimentos/isolamento & purificação , Armazenamento de Alimentos , Frutas/crescimento & desenvolvimento , Temperatura Alta , Fenóis/análise , Extratos Vegetais/química , Prunus/química , Prunus/crescimento & desenvolvimento , Óleo de Brassica napus , Rosa/química , Rosa/crescimento & desenvolvimento , Rosaceae/crescimento & desenvolvimento , Sambucus/crescimento & desenvolvimento , Sorbus/química , Sorbus/crescimento & desenvolvimento
5.
J Am Oil Chem Soc ; 90(8): 1101-1109, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23913975

RESUMO

γ-Oryzanol, a natural mixture of ferulic acid esters of triterpene alcohols and sterols, are an important bioactive components present in rice bran oil. In light of the recent increase in the popularity of wild rice among consumers, and the possibility of a direct relationship between γ-oryzanol composition and its bioactivity, the oryzanol profile of major wild rice (Zizania palustris) grown in North America was studied and compared to regular brown rice (Oryza sativa L.). A total of twenty-three γ-oryzanol components were separated, identified and quantified by HPLC coupled to an Orbitrap MS. The distribution of individual γ-oryzanols was similar for all the wild rice but significantly different from those of the regular brown rice. Unlike in the regular brown rice, a significant amount of steryl caffeate and cinnamate were found in the wild rice samples. Generally, the amounts of γ-oryzanol in the wild rice were higher compared to the regular brown rice, 1,352 vs. 688 µg/g. The results from this study showed that wild rice had a more diverse γ-oryzanol composition and the higher amounts compared to the regular brown rice.

6.
J Agric Food Chem ; 61(11): 2648-54, 2013 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-23414530

RESUMO

Cereal coffee is a coffee substitute made mainly from roasted cereals such as barley and rye (60-70%), chicory (15-20%), and sugar beets (6-10%). It is perceived by consumers as a healthy, caffeine free, non-irritating beverage suitable for those who cannot drink regular coffee made from coffee beans. In presented studies, typical Polish cereal coffee brew has been subjected to the key odorants analysis with the application of gas chromatography-olfactometry (GC-O) and aroma extract dilution analysis (AEDA). In the analyzed cereal coffee extract, 30 aroma-active volatiles have been identified with FD factors ranging from 16 to 4096. This approach was also used for characterization of key odorants in ingredients used for the cereal coffee production. Comparing the main odors detected in GC-O analysis of roasted cereals brew to the odor notes of cereal coffee brew, it was evident that the aroma of cereal coffee brew is mainly influenced by roasted barley. Flavor compound identification and quantitation has been performed with application of comprehensive multidimentional gas chromatography and time-of-flight mass spectrometry (GCxGC-ToFMS). The results of the quantitative measurements followed by calculation of the odor activity values (OAV) revealed 17 aroma active compounds of the cereal coffee brew with OAV ranging from 12.5 and 2000. The most potent odorant was 2-furfurylthiol followed by the 3-mercapto-3-methylbutyl formate, 3-isobutyl-2-methoxypyrazine and 2-ethyl-3,5-dimethylpyrazine, 2-thenylthiol, 2,3-butanedione, 2-methoxy phenol and 2-methoxy-4-vinyl phenol, 3(sec-butyl)-2-methoxypyrazine, 2-acetyl-1-pyrroline, 3-(methylthio)-propanal, 2,3-pentanedione, 4-hydroxy-2,5-dimethyl-3-(2H)-furanone, (E,E)-2,4-decadienal, (Z)-4-heptenal, phenylacetaldehyde, and 1-octen-3-one.


Assuntos
Bebidas/análise , Grão Comestível/química , Compostos Orgânicos Voláteis/química , Culinária , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Odorantes/análise , Olfatometria , Paladar
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