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1.
Prog Lipid Res ; 96: 101290, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39094698

RESUMO

Plants and algae play a crucial role in the earth's ecosystems. Through photosynthesis they convert light energy into chemical energy, capture CO2 and produce oxygen and energy-rich organic compounds. Photosynthetic organisms are primary producers and synthesize the essential omega 3 and omega 6 fatty acids. They have also unique and highly diverse complex lipids, such as glycolipids, phospholipids, triglycerides, sphingolipids and phytosterols, with nutritional and health benefits. Plant and algal lipids are useful in food, feed, nutraceutical, cosmeceutical and pharmaceutical industries but also for green chemistry and bioenergy. The analysis of plant and algal lipidomes represents a significant challenge due to the intricate and diverse nature of their composition, as well as their plasticity under changing environmental conditions. Optimization of analytical tools is crucial for an in-depth exploration of the lipidome of plants and algae. This review highlights how lipidomics analytical tools can be used to establish a complete mapping of plant and algal lipidomes. Acquiring this knowledge will pave the way for the use of plants and algae as sources of tailored lipids for both industrial and environmental applications. This aligns with the main challenges for society, upholding the natural resources of our planet and respecting their limits.

2.
Membranes (Basel) ; 13(3)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36984685

RESUMO

Electrospinning was used to create fibrous polylactide (PLA) materials loaded with Portulaca oleracea (P. oleracea) plant extract obtained by supercritical carbon dioxide. Morphological, physico-chemical, mechanical, and biological characteristics of the fibers were studied. According to the SEM results, the diameters of smooth and defect-free fibers fabricated by a one-pot electrospinning method were at micron scale. All the obtained materials possess good mechanical properties. Additionally, it was found that the composite fibers exhibited considerable antioxidant activity. The antimicrobial activity of the fibrous materials against Gram-positive and Gram-negative bacteria was determined as well. In vitro studies showed that the electrospun biomaterials had no cytotoxic effects and that the combination of PLA and the P. oleracea extract in the fiber structure promoted cell survival and proliferation of normal mouse fibroblasts. The obtained results reveal that microfibrous mats containing the polyester-PLA and the plant extract-P. oleracea can be suitable for applications in wound healing.

3.
Molecules ; 28(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36771103

RESUMO

Gamma irradiation has been applied as an efficient and inexpensive method for the sterilization of nuts for years. However, along with the benefits of such treatment, negative effects are possible because of the formation of reactive oxygen species with a toxic effect on important biologically active substances. Because of the scarce and contradictory information in the literature about gamma-irradiated almonds, the aim of our work was the examination of the lipid changes, antioxidant activity, and oxidative stability of almonds treated by 10 and 25 kGy gamma rays, as well as changes in intensity of the EPR spectra as an indicator for the stability of radiation-induced free radicals. The results revealed no significant differences in the EPR spectra of almonds treated at 10 and 25 kGy doses, neither in their intensity nor in kinetic behaviour. The EPR signals decayed exponentially over 250 days, with a decreasing of central line by 90%, with satellite lines by about 73%. No significant changes in the fat content, fatty acids composition, and acid value of irradiated almonds were observed. However, the amount of (alpha)tocopherols decreased from 292 to 175 mg/kg, whereas the conjugated dienes and trienes increased, K232 from 1.3 to 3 and K268 from 0.04 to 0.15, respectively, with the increasing of irradiation dose. The same was observed for total polyphenols in defatted almonds (1374 to 1520 mg/100 g), where in vitro antioxidant activity determined by ORAC and HORAC methods increased from 100 to 156 µmol TE/g and from 61 to 86 µmol GAE/g, respectively. The oxidative stability of oil decreased from 6 to 4 h at 120 °C and from 24.6 to 18.6 h at 100 °C (measured by Rancimat equipment). The kinetic parameters characterizing the oxidative stability of oil from 10 kGy irradiated almonds were studied before and after addition of different concentrations of ascorbyl palmitate as a synergist of tocopherols. Its effectiveness was concentration-dependent, and 0.75 mM ensured the same induction period as that of non-irradiated nut oil. Further enrichment with alpha-tocopherol in equimolar ratio with palmitate did not improve the oil stability. In conclusion, gamma irradiation is an appropriate method for the treatment of almonds without significant changes in fat content and fatty acids composition. The decreasing of oxidative stability after higher irradiation could be prevented by the addition of ascorbyl palmitate.


Assuntos
Antioxidantes , Prunus dulcis , Nozes , Ácidos Graxos , Espectroscopia de Ressonância de Spin Eletrônica , Tocoferóis , Estresse Oxidativo , Raios gama
4.
Molecules ; 27(6)2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35335128

RESUMO

Gamma irradiation is efficiently applied to many foods, but nevertheless there is a distinct lack of information about the changes of macro- and micronutrients (e.g., carbohydrates, lipids, organic acids, and phenolics) in dried rose hip (RH) fruits. Therefore, in this study, for the first time, the effect of gamma irradiation (10 and 25 kGy) on RH constituents is investigated. Different analytical techniques (GC-FID, HPLC-UV, HPSEC-RID, IR-FT, and SEM) are employed to examine this effect. The irradiation treatment (10 kGy) increased the glucose content by 30% and released cellobiose from RH fruits, thus revealing cellulose destruction. The extractability of total uronic acids increased from 51% (control) to 70.5% (25 kGy-irradiated), resulting in a higher pectin yield (10.8% < 12.8% < 13.4%) and molecular heterogeneity. Moreover, de-esterification was not a major effect of the irradiation-induced degradation of pectin. The sample exposure to the highest dose did not change the content of total carotenoids, ß-carotene, and (un)saturated fatty acids, but it affected the tocopherols levels. Gamma rays had a negligible effect on the phenolic constituents and did not affect ORAC and HORAC antioxidant activity. In conclusion, it can be compromised that the exposition of dried RH is safe and can be successfully applied to decontaminate fruits without affecting their nutritional value and biological activity.


Assuntos
Rosa , Ácido Ascórbico , Frutas , Pectinas , Compostos Fitoquímicos
5.
J Ethnopharmacol ; 281: 114528, 2021 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-34418509

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The argan [Argania spinosa (L.) Skeels] is one of the most important floristic resource in Morocco, it is the only representative of the Sapotaceae family and Argania genus found in Morocco. This tree is fully exploited by the native populations for nutrition, medication and cosmetics. The argan oil extracted from seed is the main tree product for his large use. AIM OF THE REVIEW: This review describes the traditional uses, chemical composition and biological activities of different the argan tree parts. MATERIALS AND METHODS: This review covers the literature available from 1972 to 2021. The informations were collected from electronic databases Scopus, PubMed, Web of Science, SciFinder and Google Scholar. RESULTS: Argan oil have been used for nutrition, and to treat several diseases, namely rheumatisms, hypercholesterolemia, atherosclerosis, lung infections, newborn gastrointestinal disorders, diabetes, skin and hair hydration. The other parts of Argan tree have been used to treat intestinal disorders, dermatosis, and hair caring, with additional uses such as livestock nutrition, carpentry and heating. The argan oil is primarily composed of unsaturated fatty acids mainly oleic and linoleic acids furthermore the chemical composition, of the others part, are very diversified (flavonoids, terpenoids, triacylglycerols, saponins. …). Diverse biological activities have been reported for argan oil, such as antioxidant, skin water retention, hair protection, cholesterol stabilization, antidiabetic, anticancer and antibacterial. Antimicrobial activities have been reported for argan leaves essential oils, when the fruit pulp organic extract presented very interesting antioxidant activity due to the presence of polyphenols. The argan cake is the seed waste produced during the extraction process, it is traditionally used for skin care and for livestock nutrition. Different biological activities of argan cake have been cited essentially antioxidant, haemoprotective, anti-inflammatory and antimicrobial.


Assuntos
Etnobotânica , Compostos Fitoquímicos/farmacologia , Fitoterapia , Plantas Medicinais/química , Sapotaceae/química , Humanos
6.
Eng Life Sci ; 18(12): 949-954, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32624889

RESUMO

The achievement of an effective process of 9α-hydroxylation of 4-androstene-3,17-dione is of significant importance as it leads to the formation of the key intermediate 9α-hydroxy-4-androstene-3,17-dione which is not possible by chemical means. In this study, the 9α-hydroxylation of 4-androstene-3,17-dione was carried out by resting Rhodococcus sp. cells. The ability of the naturally hydrophobic Rhodococcus to assimilate n-alkanes was employed to obtain a cell depot with an intentionally increased cell surface hydrophobicity. The control Rhodococcus sp. cells were cultivated on medium containing glucose instead of n-alkanes as a source of carbon and energy. Cells were harvested, washed from the cultivation media, and subjected to transformation of crystal androstenedione in buffer medium. The hydrophobicity of the n-alkanes- and glucose-grown cells, their total lipid content, and fatty acid composition were determined. The ultrastructure of the n-alkanes- and glucose-grown cells and their steroid hydroxylating activities were examined and compared. The results obtained in the present study showed that the intentionally achieved growth-driven enhancement of the already hydrophobic Rhodococcus sp. cells made them even more compatible with the hydrophobic steroid substrate and enhanced its accessibility, which provided an increased steroid hydroxylating activity and lack of the accompanying product destruction.

7.
J Agric Food Chem ; 61(25): 6086-91, 2013 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-23738954

RESUMO

Bioaccessibility of four essential (Fe, Cu, Mn, Zn) and two toxic (Cd, Pb) elements in kernels of four walnut and four hazelnut cultivars was investigated using sequential enzymolysis approach and atomic absorption spectrometry. It was found that the assimilable part of elements was not dependent on nut cultivar. The bioaccessible fraction of Cu, Mn, and Zn was definitely higher for hazelnuts (62% Cu, 39% Mn, 58% Zn) than for walnuts (14% Cu, 21% Mn, 15% Zn). Bioaccessible Fe was 20-24% from its total content for both nut types. Solubility in the simulated intestinal juice is affected by both formation of stable soluble complexes and back sorption of dissolved elements on nut solid residues. Lead shows strong insolubility due to the high sorption affinity of lead ions to the insoluble fraction of nuts. Thus, walnuts and hazelnuts could act as effective biosorbents for lead detoxication.


Assuntos
Cádmio/análise , Cobre/análise , Corylus/química , Enzimas/metabolismo , Intestinos/enzimologia , Ferro/análise , Juglans/química , Chumbo/análise , Zinco/análise , Cádmio/metabolismo , Cobre/metabolismo , Corylus/metabolismo , Digestão , Humanos , Mucosa Intestinal/metabolismo , Ferro/metabolismo , Juglans/metabolismo , Chumbo/metabolismo , Modelos Biológicos , Sementes/química , Sementes/metabolismo , Zinco/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-23168239

RESUMO

Applying gas chromatography-mass spectrometry of 4,4-dimethyloxazoline fatty acid derivatives, the fatty acid composition of 15 mushroom species belonging to 9 genera and 5 families of order Agaricales growing in Bulgaria is determined. The structure of 31 fatty acids (not all present in each species) is unambiguously elucidated, with linoleic, oleic and palmitic acids being the main components (ranging between 70.9% (Marasmius oreades) and 91.2% (Endoptychum agaricoides)). A group of three hexadecenoic positionally isomeric fatty acids, 6-, 9- and 11-16:1, appeared to be characteristic components of the examined species. By applying chemometrics it was possible to show that the fatty acid composition closely reflects the classification of the species.


Assuntos
Agaricales/química , Agaricales/classificação , Ácidos Graxos/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Agaricales/isolamento & purificação
9.
Anal Sci ; 28(9): 837-44, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22975910

RESUMO

An effort is made to critically present the achievements in silver ion chromatography during the last decade. Novelties in columns, mobile-phase compositions and detectors are described. Recent applications of silver ion chromatography in the analysis of fatty acids and triacylglycerols are presented while stressing novel analytical strategies or new objects. The tendencies in the application of the method in complementary ways with reversed-phase chromatography, chiral chromatography and, especially, mass detection are outlined.


Assuntos
Ácidos Graxos/análise , Prata/química , Triglicerídeos/análise , Cromatografia Líquida de Alta Pressão/história , Cromatografia em Camada Fina/história , Ácidos Graxos/história , História do Século XXI , Íons/química , Íons/história , Prata/história , Extração em Fase Sólida/história , Triglicerídeos/história
10.
J AOAC Int ; 94(1): 4-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21391475

RESUMO

A silver ion HPLC procedure is described that is suitable to determine the fatty acid composition of plant seed oils. After conversion of fatty acids to p-methoxyphenacyl derivatives, it was possible to achieve baseline resolution of all fatty acid components with 0 to 3 double bonds, including the positionally isomeric 18:1 fatty acids oleic acid (cis 9-18:1), petroselinic acid (cis 6-18:1), and cis-vaccenic acid (cis 11-18:1), in aniseed oil (Pimpinella anisum, Apiaceae) by a single gradient run on a single cation exchange column laboratory converted to the silver ion form. The UV detector response (280 nm) was linearly related to the fatty acid concentration in the range 0.01 to 3.5 mg/mL.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ácidos Graxos/análise , Pimpinella/química , Óleos de Plantas/química , Cromatografia Gasosa , Ácidos Graxos/química , Isomerismo , Sementes/química , Prata , Espectrofotometria Ultravioleta
11.
Nat Protoc ; 5(3): 473-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20203664

RESUMO

A protocol for separation of positionally isomeric trans- and cis-octadecenoic fatty acids as their p-methoxyphenacyl esters, using a single column silver ion high-performance liquid chromatography (Ag-HPLC) with UV detection, is described. The procedure involves hydrolysis of oil to free fatty acids, derivatization to p-methoxyphenacyl esters, purification and separation by Ag-HPLC. The procedure is robust and relatively rapid. In total, it takes about 16 h or overnight and a further 5 h to carry out. Its feature and value consist in the application of p-methoxyphenacyl esters in Ag-HPLC, thus ensuring excellent simultaneous separation of both configurational and positional fatty acid isomers on a single column by a single run. Quantification is not affected by the fatty acid structure, and the method is highly sensitive. As fatty acid isomerization is a strong evidence for adulteration of lipid-containing food products with chemically modified oils and fats, the procedure is especially appropriate for detection and authenticity analysis in many areas of food manufacturing and quality control.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ácidos Oleicos/isolamento & purificação , Óleos de Plantas/química , Esterificação , Contaminação de Alimentos/análise , Hidrólise , Isomerismo , Prata
12.
J Sep Sci ; 29(17): 2578-83, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17313097

RESUMO

Complete regioselective separation of five pairs of isomeric dipalmitoyl polyalkenoyl glycerols with two to six double bonds in the unsaturated acyl residues has been achieved by RP-HPLC on a single ODS column. Four ODS columns with stationary phases containing different percentages of free silanol groups have been tested. Binary mobile phases of ACN admixed with dichloromethane, tetrahydrofuran, 1-propanol, 2-propanol, ethanol, or acetone have been examined. The choice of modifier depended on the nature of the stationary phase. The more polar solvents were better suited for stationary phases with higher percentage of free silanol groups. Isomeric species were eluted according to chain length, number of double bonds, and the position of the unsaturated acyl chain in the glycerol molecule. Retention increases in the order 20:5 < 22:6 < 18:3 < 20:4 << 18:2. Within each isomeric pair, the species with unsaturated acyl chain occupying either the sn-1- or the 3-position were retained preferentially. Complete simultaneous regioselective separation of 10 isomeric triacylglycerols in a single isocratic run on a single ODS column was demonstrated.


Assuntos
Triglicerídeos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Isomerismo , Triglicerídeos/química
13.
J Chromatogr Sci ; 43(9): 494-9, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16212797

RESUMO

A simple and highly sensitive method for determining the fatty acid composition of food lipids containing conjugated linoleic acid (CLA) is described. The method is based on the separation of the 9-anthrylmethyl ester derivatives of saturated and unsaturated (conjugated and non-conjugated) fatty acids by reversed-phase high-performance liquid chromatography with fluorescence detection. Just like the other fatty acids, CLA reacts readily with 9-anthryldiazomethane at room temperature to produce 9-anthrylmethyl esters without isomerization and decomposition of the conjugated double bonds. Clear resolution of the individual fatty acids as their 9-anthrylmethyl esters is achieved on a highly efficient octadecylsilylated silica column (150- x 3-mm i.d., 3-microm particle size) using a stepwise gradient elution with methanol-water. The method is standardized with commercially available CLA isomers (cis-9, trans-11 and trans-10, cis-12-octadecadienoic acids, and their cis,cis and trans,trans isomers) and applied for determination of the fatty acid compositions of milk and sdairy products.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ácidos Linoleicos Conjugados/análise , Espectrometria de Fluorescência/métodos , Animais , Bovinos , Laticínios/análise , Ésteres , Ácidos Linoleicos Conjugados/química
14.
J Sep Sci ; 27(12): 1033-6, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15352724

RESUMO

The ability of reversed-phase high-performance liquid chromatography (RP-HPLC) to separate some positionally isomeric disaturated and monounsaturated triacylglycerols (TAGs) as intact species is demonstrated for the first time. Mobile phases of acetonitrile modified with methanol, ethanol, 2-propanol, 1-propanol, 1-butanol, acetone, or dichloromethane were tested for the separation of POP-PPO, PLP-PPL, PEP-PPE, and PDP-PPD (P-palmitic, O-oleic, L-linoleic, E-eicosapentaenoic, D-docosahexaenoic acid residue) on a single RP-HPLC column. The resolution improved with increasing number of double bonds in the acyl residues. While POP and PPO were only partially resolved, PDP and PPD were fully separated with all tested mobile phases, except those containing methanol. Also separated were the four TAGs having the same equivalent carbon number (ECN = 42), PEP, PPE, PDP, and PPD, on a single RP-HPLC column with mobile phase acetonitrile-2-propanol (70:30, v/v) at 0.8 mL/min. In all cases the isomer with the unsaturated acyl residue in either 1- or 3-position was retained more strongly than the respective 2-isomer.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Triglicerídeos/análise , Triglicerídeos/química , Cromatografia Líquida , Ácidos Docosa-Hexaenoicos/análise , Ácido Eicosapentaenoico/análise , Ácido Linoleico/análise , Ácido Oleico/análise , Isoformas de Proteínas , Fatores de Tempo
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