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1.
Heliyon ; 9(4): e14857, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37025912

RESUMO

Berry consumption is increasing worldwide due to their high content of bioactive compounds. However, such fruits have a very short shelf life. To avoid this drawback and to offer an effective alternative for its consumption at any time of the year, an agglomerated berry powder mix (APB) was developed. The aim of this work was to evaluate the stability of APB during a 6-months-period storage at 3 temperatures. The stability of APB was determined by moisture, aw, antioxidant activity, total phenolics, total anthocyanins, vitamin C, color, phenolic profiles, and MTT assay. APB showed differences in antioxidant activity between 0 and 6 months. It experimented non-enzymatic browning, which was more remarkable at 35 °C. APB at time 0 exhibited growth inhibitory effects against HT-29 human cancer cells. Most properties were significantly modified by storage temperature and time, which induces a significant decreasing of bioactive compounds.

2.
Foods ; 12(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36900601

RESUMO

The fillets and roes of 29 species of dry-salted fishes consumed in Eurasian countries were analyzed for fatty acids (FAs), tocols, and squalene, looking for derived health benefits. FAs were analyzed by GC-FID, and tocols and squalene were analyzed by HPLC-DAD. With some exceptions, docosahexaenoic (DHA, 22:6n-3), eicosapentaenoic (EPA, 20:5n-3), and arachidonic (ARA, 20:4n-6) acids were the prominent polyunsaturated fatty acids (PUFAs). The fillets of Scardinius erythrophthalmus reached the highest amounts of total FAs, ARA, and DHA (23.1, 1.82, and 2.49 mg/100 g). The fillets of Seriola quinqueradiata showed the highest percentages of DHA (34.4% of total FAs). Nutritional quality indices for fish lipids were favorable in all samples, especially the n-6/n-3 PUFA ratio, which was below 1 in most cases. α-Tocopherol was found in all fillets and roes, especially in Cyprinidae and Pleuronectidae species, and the highest value was found in the roes of Abramis brama (5.43 mg/100 g). Most samples contained tocotrienols at trace levels. The fillets of Clupeonella cultriventris contained the highest amounts of squalene (1.83 mg/100 g). Overall, dry-salted fish stand out due to their high concentrations of ARA, EPA, and DHA, as well as for α-tocopherol concentrations in roes.

3.
Plants (Basel) ; 12(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36678939

RESUMO

Seeds of most Arecaceae species are an underutilized raw material that can constitute a source of nutritionally relevant compounds. In this work, seeds of 24 Arecaceae taxa were analyzed for fatty acids (FAs) by GC-FID, for phenolics by HPLC-DAD and LC-MS, and for their antitumor activity against the HT-29 colorectal cancer cell line by the MTT assay. Lauric, oleic, and linoleic acids were the prominent FAs. Cocoseae species contained total FAs at 28.0-68.3 g/100 g seeds, and in other species total FAs were from 1.2 (Livistona saribus) to 9.9 g/100 g (Washingtonia robusta). Sabal domingensis, Chamaerops humilis, and Phoenix dactylifera var. Medjool had unsaturated/saturated FA ratios of 1.65, 1.33-1.78, and 1.31, respectively, and contained 7.4, 5.5-6.3, and 6.4 g FAs/100 g seeds, respectively. Thus, they could be used as raw materials for healthy oilseed production. Phenolics ranged between 39 (Livistona fulva) and 246 mg/100 g (Sabal palmetto), and of these, caffeic acid, catechin, dactylifric acid, and rutin had the highest values. (-)-Epicatechin was identified in most seed extracts by LC-MS. Hydroalcoholic extracts from five species showed a dose-dependent inhibitory effect on HT-20 cells growth at 72 h (GI50 at 1533-1968 µg/mL). Overall, Arecaceae seeds could be considered as a cheap source of health-promoting compounds.

4.
Food Res Int ; 157: 111421, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35761667

RESUMO

Ahiflower oil© is extracted from the seeds of Buglossoides arvensis, which contains high amounts of stearidonic acid (SDA, 18:4n-3), while its phenolic composition still is unreported. Moreover, several Buglossoides taxa remain unstudied and could become natural sources of SDA. In this work, seeds of several Buglossoides taxa and Ahiflower oil© were screened for fatty acids, phenolic compounds, and in vitro antiproliferative activities against colorectal cancer cells. Four flavonoids and 16 phenolic acids were identified and quantified. Among Buglossoides taxa, the highest amounts of phenolic compounds were found in samples collected in Spain, under a warm Mediterranean climate. Rosmarinic and lithospermic acids were the main phenols found in Buglossoides seeds. The MTT assay showed dose- and time-dependent inhibitory effects of B. arvensis extracts on HT-29 cancer cells, with a GI50value of ∼280 µg/mL after 72 h of cell exposure to seed extracts. The latter showed lower antiproliferative activity than that of pure phenolics due to the simultaneous presence of other compounds in the extracts, as evidenced by 1H NMR. This work constitutes the first approach to evaluate the seeds of several Buglossoides taxa as functional oils-providers to use them as functional foods.


Assuntos
Boraginaceae , Ácidos Graxos Ômega-3 , Fenóis , Extratos Vegetais , Boraginaceae/química , Ácidos Graxos Ômega-3/química , Células HT29 , Humanos , Fenóis/química , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Óleos de Plantas/química , Sementes/química
5.
Plant Foods Hum Nutr ; 76(3): 385-393, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34328593

RESUMO

γ-linolenic acid (GLA, 18:3n-6) is a bioactive fatty acid (FA) that exerts several healthy actions; however, its occurrence is restricted to a few oils. The goal of this study was to detect GLA-rich Ribes species and cultivars (cv), and to achieve this the seeds of 7 Ribes taxa and 50 Ribes cv were surveyed for FA profiles. The highest GLA percentages were found in R. nigrum cv 'Plotnokistnaya', 'Volshebnica', 'Atlant' and 'Nara' (22.6, 22.1, 20.9, and 20.0% of total FA, respectively) and also in R. komarovii (19.6%) and R. nigrum var. sibiricum (18.3%). Stearidonic acid (SDA, 18:4n-3) had the highest values in both R. rubrum 'Konstantinovskaya' and R. niveum 'Smolyaninovskaya' (4.8%). GLA content ranged from 0.4 in some R. rubrum cv and R. niveum 'Smolyaninovskaya' to 3.5 g/100 g seeds in R. nigrum 'Plotnokistnaya'. Principal component analysis (PCA) was performed using PUFA profiles, which allowed grouping Ribes sections as well as black currant cv derived from different pedigree within the section Coreosma. All taxa and cv checked here are valuable by-product sources, given the high GLA percentages contained in their seed oils. Such cv could be used for healthy oils production, as well as for breeding to obtain new cv with improved GLA concentrations.


Assuntos
Ribes , Ácido gama-Linolênico , Ácidos Graxos , Óleos de Plantas , Sementes
6.
Plant Foods Hum Nutr ; 76(2): 210-218, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33825091

RESUMO

Recent studies show that vegetables at early stage of development contain higher amounts of phytonutrients and minerals, and lower amounts of nitrates than at fully developed stage. Nevertheless, the effects of some spectrum light on the carotenoid content of lettuce microgreens are unknown. Three different LED lamps were checked: (i) artificial white light (T0); (ii) continuous light-emitting diodes with longer blue-wavelength (T1), and (iii) continuous light-emitting diodes with longer red-wavelength (T2). Different lettuce cvs. were grown under the above described lamps. Plants were collected after 10, 15, 35 and 50 days from planting to produce sprouts, microgreens, initial baby leaf, and baby leaf, respectively. Response to different continuous spectrum lights related to productivity and nitrate content was variable for the different plants. Accumulation of nitrates at initial stages in plant tissues was clearly lower than at final stages of crop development, ranging from 50.2 to 73.4 mg 100 g1 fresh weight for T2. Lettuce consumption is preferable at microgreen stage in comparison with baby leaf stage. Nitrate amounts at microgreen stage were lower than in baby leaf stage, and this content was inversely correlated with carotenoid content, which in tissues was higher at microgreens stage influenced by LED.


Assuntos
Lactuca , Nitratos , Carotenoides , Luz , Folhas de Planta
7.
Food Chem ; 350: 128635, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33317855

RESUMO

In this work, seeds from selected Mertensia species were analyzed for γ-linolenic acid-rich oils and minor functional compounds. Fatty acids (FA) were analyzed by GC-FID; tocopherols, sterols, squalene, and phenolics compounds by HPLC-DAD, and the structures of the latter were confirmed by LC-MS. M. maritima spp. asiatica and M. sibirica showed the highest amounts of γ-linolenic acid (22.8 and 18.7%, respectively) and total FA (15.9 and 10.9 g/100 g seeds, respectively). M. sibirica had the greatest levels of sterols, phenolics and tocopherols (244.8, 243.9 and 66.3 mg/100 g, respectively), in which stigmasterol, rosmarinic acid and α-tocopherol (237.7, 180.1 and 53.6 mg/100 g, respectively) were the most abundant components. M. maritima spp. asiatica and M. arizonica showed the highest amounts of squalene (2.5 and 1.1 mg /100 g seeds). Mertensia species constitute a new source of GLA-rich oils, suitable to be marketed by the pharmaceutical and food industries.


Assuntos
Boraginaceae/embriologia , Sementes/química , Ácido gama-Linolênico/análise , Cromatografia Gasosa , Ácidos Graxos/análise , Fitosteróis/análise , Óleos de Plantas/química , Esqualeno/análise , Esteróis/análise , Tocoferóis/análise
8.
Chem Biodivers ; 17(12): e2000627, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33045128

RESUMO

Thirty Boraginaceae species from different tribes were evaluated in a search of γ-linolenic (GLA, 18:3n-6) and stearidonic acid (SDA, 18:4n-3)-rich oils. The high GLA percentages were found in the seed oils of Symphytum bulbosum and S. tuberosum subsp. tuberosum (27.6 and 27.2 % of total fatty acids (FA)), which are unusually high values for GLA-oils in the current literature. On the whole seed, noticeable GLA percentages were found in S. grandiflorum, S. tuberosum subsp. tuberosum and Borago officinalis (7.43, 4.90, and 4.51 g/100 g, respectively). The main SDA-taxa detected in this study were Buglossoides arvensis, B. incrassata and Glandora oleifolia (21.3, 18.9, and 16.3 % of total fatty acids). On total seed weight, Glandora rosmarinifolia showed the highest SDA content (3.57 g/100 g). Finally, the higher FA contents were found in S. grandiflorum and Paramoltkia doerfleri seeds (35.2 and 37.0 g/100 g, respectively). Principal component analysis showed that similarities in FA profiles allow grouping species as botanical criteria for Boraginaceae tribes do, while the FA groupings confirm the metabolic activities of desaturase and elongase enzymes. Data on the FA composition of the seed oils analyzed here suggest their potential use as functional foods and can be considered as novel sources of SDA and GLA.


Assuntos
Boraginaceae/química , Ácidos Graxos Ômega-3/isolamento & purificação , Óleos de Plantas/química , Sementes/química , Ácido gama-Linolênico/isolamento & purificação , Região do Mediterrâneo , Análise de Componente Principal
9.
Toxicol Res (Camb) ; 9(4): 474-483, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32905142

RESUMO

α-Linolenic acid (ALA, 18:3n-3) and γ-gamma linolenic acid (GLA, 18:3n-6) are polyunsaturated fatty acids (PUFA) that improve the human health. The present study focused on testing the in vitro antitumor actions of pure ALA and GLA on the HT-29 human colorectal cancer cell line. Cell viability was checked by MTT ((3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test, cell membrane damage by the lactate dehydrogenase assay, apoptosis was tested by both caspase-3 activity trial and transmission electron microscopy images, and protein composition was analyzed by quantitative proteomics analysis. MTT test revealed IC50 values of 230 and 255 µM for ALA and GLA, respectively, at 72 h. After 24 h of incubation, both ALA and GLA induced apoptosis on HT-29 colorectal cancer cells according to the caspase-3 assay and microscopy images. SWATH/MS analysis evidenced that ALA significantly affected the mitochondrial protein import pathway and the citric acid cycle pathway, while GLA did not significantly affect any particular pathway. In summary, both ALA and GLA showed concentration-dependent inhibitory effects on HT-29 cells viability and induced cell death by apoptosis. ALA significantly affected cellular pathways, while GLA does not have specific actions on either pathway. Both n-3 and n-6 C18 PUFA are bioactive food components useful in the colorectal cancer prevention.

10.
Nutrients ; 11(12)2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31817645

RESUMO

Colorectal cancer (CRC) is one of the most common and mortal types of cancer. There is increasing evidence that some polyunsaturated fatty acids (PUFAs) exercise specific inhibitory actions on cancer cells through different mechanisms, as a previous study on CRC cells demonstrated for two very long-chain PUFA. These were docosahexaenoic acid (DHA, 22:6n3) and arachidonic acid (ARA, 20:4n6) in the free fatty acid (FFA) form. In this work, similar design and technology have been used to investigate the actions of both DHA and ARA as monoacylglycerol (MAG) molecules, and results have been compared with those obtained using the corresponding FFA. Cell assays revealed that ARA- and DHA-MAG exercised dose- and time-dependent antiproliferative actions, with DHA-MAG acting on cancer cells more efficiently than ARA-MAG. Sequential window acquisition of all theoretical mass spectra (SWATH) - mass spectrometry massive quantitative proteomics, validated by parallel reaction monitoring and followed by pathway analysis, revealed that DHA-MAG had a massive effect in the proteasome complex, while the ARA-MAG main effect was related to DNA replication. Prostaglandin synthesis also resulted as inhibited by DHA-MAG. Results clearly demonstrated the ability of both ARA- and DHA-MAG to induce cell death in colon cancer cells, which suggests a direct relationship between chemical structure and antitumoral actions.


Assuntos
Antineoplásicos/farmacologia , Ácido Araquidônico/farmacologia , Ácidos Docosa-Hexaenoicos/farmacologia , Monoglicerídeos/farmacologia , Morte Celular/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Replicação do DNA/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células HT29 , Humanos , Espectrometria de Massas , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , Proteômica
11.
Food Chem ; 301: 125309, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31398673

RESUMO

Fifty Ribes species and R. nigrum-based cultivars from eight Ribes sections were surveyed for γ-linolenic acid (GLA, 18:3, n-6)- and stearidonic acid (SDA, 18:4, n-3)-rich oils. R. pallidiflorum, R. glabellum and R. pubescens seed oils contain noticeable GLA amounts: 13.3, 11.8, and 11.9% of total fatty acids (FA), respectively. However, the highest GLA contents were found in the seed oils of several blackcurrant cultivars, highlining Ribes 'Myuryucheene' with 20.2% GLA of total FA. Principal Component Analysis showed that similarities in FA profiles allow grouping species as botanical criteria for Ribes sections do. The main GLA-taxa detected in this study correspond to blackcurrant cultivars, all of them native to Siberia. Considering that such cultivars are notable fruit-producers, its cultivation in Siberia besides producing fruits in very difficult agronomic areas, could produce a valuable by-product, i.e. the seeds, which will add economic value to agricultural systems if devoted to GLA-rich oils extraction.


Assuntos
Óleos de Plantas/química , Ribes/química , Ácido gama-Linolênico/análise , Ácidos Graxos/análise , Ácidos Graxos Ômega-3/análise , Frutas/química , Itália , Sementes/química , Sibéria
12.
Nutrients ; 11(7)2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31277441

RESUMO

Vegetables, once harvested and stored on supermarket shelves, continue to perform biochemical adjustments due to their modular nature and their ability to retain physiological autonomy. They can live after being harvested. In particular, the content of some essential nutraceuticals, such as carotenoids, can be altered in response to environmental or internal stimuli. Therefore, in the present study, we wondered whether endogenous rhythms continue to operate in commercial vegetables and if so, whether vegetable nutritional quality could be altered by such cycles. Our experimental model consisted of rocket leaves entrained under light/darkness cycles of 12/12 h over 3 days, and then we examined free-run oscillations for 2 days under continuous light or continuous darkness, which led to chlorophyll and carotenoid oscillations in both constant conditions. Given the importance of preserving food quality, the existence of such internal rhythms during continuous conditions may open new research perspective in nutrition science. However, while chromatographic techniques employed to determine pigment composition are accurate, they are also time-consuming and expensive. Here we propose for the first time an alternative method to estimate pigment content and the nutritional quality by the use of non-destructive and in situ optical techniques. These results are promising for nutritional quality assessments.


Assuntos
Brassicaceae/metabolismo , Carotenoides/metabolismo , Clorofila A/metabolismo , Ritmo Circadiano , Armazenamento de Alimentos , Valor Nutritivo , Folhas de Planta/metabolismo , Verduras/metabolismo , Brassicaceae/efeitos da radiação , Carotenoides/efeitos da radiação , Clorofila A/efeitos da radiação , Ritmo Circadiano/efeitos da radiação , Embalagem de Alimentos , Fotoperíodo , Folhas de Planta/efeitos da radiação , Fatores de Tempo , Verduras/efeitos da radiação , Zeaxantinas/metabolismo
13.
PLoS One ; 14(2): e0207106, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30779750

RESUMO

Borage is a well-known plant of great importance in human nutrition and health. Expanding knowledge of particular plants that have anti-cancer products is a global concern. There is substantial information regarding the benefits, presence and extraction of gamma linolenic acid (GLA; 18:3n6) in different plants around the world, especially in borage seeds. However, there is little information concerning the effects of the salinity of the nutrient solution on the growth and presence of GLA in borage seeds. The objective of this work was to determine the optimal salinity of the nutrient solution for obtaining GLA in soilless cultivation systems. Borage plants were grown in coconut fibre and provided three treatments of nutrient solution of 2.20, 3.35 and 4.50 dS m-1, increasing solution salinity with the standard nutrient solution of concentrated macronutrients as a reference. Vegetative growth, seed production and GLA ratio were measured. The results of vegetative development and GLA production doubled and tripled with the increase in salinity of the nutrient solution, respectively.


Assuntos
Borago/crescimento & desenvolvimento , Óleos de Plantas/metabolismo , Sementes/crescimento & desenvolvimento , Solo/química , Ácido gama-Linolênico/metabolismo , Borago/metabolismo , Condutividade Elétrica , Sementes/metabolismo
14.
J Agric Food Chem ; 66(24): 6003-6012, 2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29804451

RESUMO

Two polyunsaturated fatty acids, docosahexaenoic acid (DHA) and arachidonic acid (ARA), as well as derivatives, such as eicosanoids, regulate different activities, affecting transcription factors and, therefore, DNA transcription, being a critical step for the functioning of fatty-acid-derived signaling. This work has attempted to determine the in vitro anticancer activities of these molecules linked to the gene transcription regulation of HT-29 colorectal cancer cells. We applied the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test along with lactate dehydrogenase and caspase-3 assays; proteome changes were assessed by "sequential windowed acquisition of all theoretical mass spectra" quantitative proteomics, followed by pathway analysis, to determine the affected molecular mechanisms. In all assays, DHA inhibited cell proliferation of HT-29 cells to a higher extent than ARA and acted primarily by downregulating proteasome particles, while ARA presented a dramatic effect on all six DNA replication helicase particles. The results indicated that both DHA and ARA are potential chemopreventive agent candidates.


Assuntos
Antineoplásicos/farmacologia , Ácidos Araquidônicos/farmacologia , Neoplasias Colorretais/genética , Ácidos Docosa-Hexaenoicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/fisiopatologia , Humanos , Proteômica
15.
Food Chem ; 218: 435-439, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-27719932

RESUMO

The aim of this work was to establish the richness in γ-linolenic acid (GLA, 18:3n6) and stearidonic acid (SDA, 18:4n3) of several Sardinian Boraginaceae species. To this end, seeds of selected species were collected from their natural habitats and analysed. The highest GLA contents were found in the seed oils of two endemic Borago taxa, i.e. B. morisiana (24.4 and 24.6% GLA of total fatty acids for samples from San Pietro Island and Sardinia Island, respectively), and 22.9% GLA for B. pygmaea. Both Borago species contained more GLA than B. officinalis collected in the same ecosystems. SDA was found in significant amounts in Echium plantagineum seed oil from the Lattias Mountains (15% SDA of total fatty acids). It is notable that both Borago GLA-rich species are under threat of extinction, thus revealing the importance of the preservation of the natural Sardinian ecosystems for endangered species and human health.


Assuntos
Boraginaceae/química , Ácido gama-Linolênico/análise , Ácidos Graxos Ômega-3/análise , Humanos , Itália , Sementes/química
16.
J Biosci Bioeng ; 115(5): 518-22, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23287502

RESUMO

Production of 2-monoacylglycerols (2-MAGs) by selective hydrolysis of the triacylglycerols (TAGs) of Echium plantagineum seed oil and Marinol and further purification was carried out. Three purification methods, including silica gel column chromatography, liquid-liquid extraction and low-temperature crystallization were assayed. Partial acyl migration during the purification step is always observed. Acyl migration rates were similar both for the column chromatography and for the liquid-liquid extraction methods, and resulted in 1-MAG/2-MAG ratios higher than 1.0. Fatty acid (FA) profiles of 2-MAGs after enzyme hydrolysis showed that the major FAs were stearidonic acid (56.9% of total FA in 2-position) and docosahexaenoic acid (63.6% of total FA in 2-position) for E. plantagineum seed oil and Marinol, respectively.


Assuntos
Dronabinol/química , Echium/química , Ácidos Graxos/análise , Monoglicerídeos/química , Óleos de Plantas/química , Ácidos Docosa-Hexaenoicos/análise , Ácidos Graxos Ômega-3/análise , Monoglicerídeos/metabolismo , Sementes/química , Triglicerídeos/metabolismo
17.
J Med Food ; 14(1-2): 40-5, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21138360

RESUMO

The cytotoxic effects of extracts of the tomato variety "Racimo" have been evaluated through the use of the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay at several concentrations. Three extracts-ethanol-water, petroleum ether, and in vitro digested tomato-exhibited in vitro cytotoxicity against the proliferation of the cultured cancer cell line HT-29. The concentration that caused 50% inhibition of cancer cell growth occurred (GI(50)) of the different extracts for HT-29 cells was 62.5 µg/mL for the petroleum ether extract and 87.0 µg/mL for the digested tomato extract. For the ethanol-water extract, it was not possible to determine this parameter at the assayed extract concentrations. These results clearly indicate that after the digestion process, the less polar substances, such as carotenoids and sterols, are bioavailable as active species against cancer cells. The GI(50) levels for tomato extracts are similar to those values reported for medicinal plants. The results of the MTT assay on nonmutagenic CCD-18 cells showed a lack of negative effect on cell growth, which indicates that tomato extracts act selectively on HT-29 tumor cells. (1)H-Nuclear magnetic resonance spectra confirmed the presence of known compounds with accepted cytotoxic activity against tumor lines (lycopene and ß-carotene). The high cytotoxicity for HT-29 cells showed by the petroleum ether extract might be due to the simultaneous presence in the extract of both carotenoids and glyceryl esters of fatty acids. The results of this work clearly indicate the importance of carotenoid consumption on colon tumor proliferation and prevention, and also the importance of the dietary fats in carotenoid bioavailability.


Assuntos
Proliferação de Células/efeitos dos fármacos , Inibidores do Crescimento/farmacologia , Extratos Vegetais/farmacologia , Solanum lycopersicum/química , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/fisiopatologia , Células HT29 , Humanos
18.
Trop Biomed ; 26(2): 149-54, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19901901

RESUMO

A chemical-ecology approach has been used to screen plants growing in Guyana Highlands as an indicator of production of biologically active secondary metabolites. Extracts of leaves from 19 species, most of them endemic in this area, and collected at the top of Roraima Tepui (2,723 m) were screened in vitro at different concentrations for their potential cytotoxic activity against three tumour cell lines: HT29 (colon), A549 (lung) and MDA-MB-231 (breast). MTT (tetrazolium blue) colorimetric assay was employed as cytotoxicity test. Extracts of nine species caused less than 30% growth in at least one cell line. From these species, high cytotoxic activity was detected in Casearia sylvestris var. lingua and Ledotamnus sessiliflorus extracts; medium activity was found in Cyathea sp. Two other species, Cyrilla racemiflora and Heliamphora minor showed lower but significant cytotoxicity. Further cytotoxicity-directed fractionation of these extracts would be advisable to isolate and identify the active principles of these plants.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Fitoterapia , Extratos Vegetais/farmacologia , Neoplasias da Mama/tratamento farmacológico , Casearia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Ericaceae , Feminino , Guiana , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Folhas de Planta/química
19.
Food Chem ; 108(3): 1023-6, 2008 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26065767

RESUMO

The antioxidant activity of the microalgal ethanolic extracts of Porphyridium cruentum, Phaeodactylum tricornutum and Chlorella vulgaris was determined by means of the ß-carotene-linoleate model system. The results show that the activity of C. vulgaris extract was higher than those obtained for the other microalgal extracts tested and for the synthetics BHA (butylated hydroxyanisole), and BHT (butylated hydroxytoluene). In addition, the major constituents present in the ethanolic extracts of the three microalgae species were analyzed by means of GC and GC-mass spectrometry. The results showed that the tested microalgae may be an important source of natural antioxidants, as an alternative to higher plants or the production by chemical synthesis.

20.
J Biosci Bioeng ; 97(5): 294-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-16233632

RESUMO

Solvent winterization of seed oil and free fatty acids (FFAs) was employed to obtain gamma-linolenic acid (GLA; 18:3omega6) concentrates from seed oils of two Boraginaceae species, Echium fastuosum and Borago officinalis. Different solutions of seed oils and FFAs from these two oils at 10%, 20% and 40% (w/w) were crystallized at 4 degrees C, -24 degrees C and -70 degrees C, respectively, using hexane, acetone, diethyl ether, isobutanol and ethanol as solvents. Best results were obtained for B. officinalis FFAs in hexane, reaching a maximum GLA concentration of 58.8% in the liquid fraction (LF). In E. fastuosum, the highest GLA concentration (39.9%) was also achieved with FFAs in hexane.

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