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1.
We report for the first time the antioxidant and antimutagenic activities of fractions from Randia echinocarpa fruit, which is a Rubiaceae plant native to Sinaloa, Mexico. This fruit has been traditionally used in the prevention or treatment of cancer, among other diseases. The pulp of the fruit was sequentially extracted with solvents of different polarity (i.e. hexane, chloroform, methanol and water). A high extraction yield was obtained with methanol (72.17% d.w.). The aqueous extract showed the highest content of phenolics (2.27 mg/g as ferulic acid equivalents) and the highest antioxidant activity based on the β-carotene bleaching method (486.15). The commercial antioxidant BHT was used as control (835.05). Antimutagenic activity of the aqueous extract (0–500 μg/tube) was evaluated using the Salmonella microsuspension assay (YG1024 strain) and 1-NP as the mutagen (50 and 100 ng/tube). The aqueous extract was neither toxic nor mutagenic and the percentage of inhibition on 1-NP mutagenicity was 32 and 53% at doses of 50 and 100 ng/tube, respectively. The results of the double incubation assay suggest that the extract inhibited the mutagenicity of 1-NP by a combination of desmutagenic and bioantimutagenic effects.  相似文献   

2.
The scavenging activity against DPPH (1,1-diphenil-2-picrylhydrazyl) radical and the antifungal effect against chloroform, ethyl acetate and 50% methanolic extracts of Verbena officinalis leaves were investigated. The activity of different fractions of 50% methanolic extract and some isolated compounds were also investigated. The results suggest that 50% methanolic extract and caffeoyl derivatives could potentially be considered as excellent and readily available sources of natural antifungal and antioxidant compounds.  相似文献   

3.
Organic solvent (methanol, ethanol, and acetone) extracts and water extracts of cherry (Prunus serrulata var. spontanea) blossoms were prepared, and antioxidant activities of the extracts were evaluated. Methanolic CBE (100 μg/ml) showed the highest total phenol content (104.30 μM), radical scavenging activity (34.2%), and reducing power (0.391). The effect of CBE on DNA damage induced by H2O2 in human leukocytes was evaluated by Comet assay. All CBE was a potent dose dependent inhibitor of DNA damage induced by 200 μM of H2O2, methanolic CBE showed the most strong inhibition activity. The methanolic CBE of 500 μg/ml showed 38.8% inhibition against growth of human colon cancer cell line HT-29. These results indicated that cherry blossoms could provide valuable bioactive materials.  相似文献   

4.
Pulque is made by fermenting the agave sap or aguamiel of Agave atrovirens with a whole array of microorganisms present in the environment including several lactic acid bacteria and yeasts such as Saccharomyces cerevisiae. Ascorbic acid was determined in pulque and aguamiel, respectively. Phytase activity in lees, liquid and freeze-dried pulque was assayed by measuring the appearance of phosphate from phytate by a colorimetric method likewise phosphate from phytate present in fresh corn tortilla was measured after in vitro incubation with pulque. Iron, zinc, calcium, magnesium and selenium contents were measured in pulque and corn tortilla as well as in nixtamalized corn flour (NCF), the latter is used to make instant tortilla, since corn provides most of the energy as well as most of the phytate in the Mexican rural diet. Pulque showed phytase activity but much less ascorbic acid and iron than previously reported; additionally, phytase in pulque hydrolyzed most of phytate’s corn tortilla. Lees, which is mostly made of pulque’s microbiota, significantly accumulated iron and zinc but no selenium. NCF was fortified with iron by the manufacturers but poorly blended. There were significant differences on selenium content between tortillas samples, apparently some soils in central Mexico are selenium deficient. Moderate pulque intake appears to increase the bioavailability of iron and zinc bound by phytate in corn.  相似文献   

5.
The indigenous pitanga (Eugenia uniflora L.) is now marketed and commercially processed in Brazil. In the present work, the carotenoids of the pitanga fruit from two states and at two stages of ripening, as well as of processed pitanga products (frozen pulp and juice, the brands being designated as A, B and C) commercialized in Campinas, São Paulo, were determined by HPLC. As compared to ripe pitanga from Medianeira, Paraná, those from Campinas had significantly higher (all-E)-lycopene (14.0 vs. 71.1 μg/g), (13Z)-lycopene (1.1 vs. 5.0 μg/g) and (all-E)-γ-carotene (1.6 vs. 3.8 μg/g) levels. Significant increases in most of the carotenoids occurred from the partially ripe to the ripe fruits, with (all-E)-lycopene doubling its concentration in fruits from both states. Pitanga was found to be one of the richest fruit sources of carotenoids, particularly lycopene, but the processed products had much lower lycopene content. The mean (all-E)-lycopene concentration was 16.6 μg/g for frozen pulp brand A, 23.0 μg/g for bottled juice brand B and 25.6 μg/g for bottled juice brand C. Optimization of processing is therefore needed to guarantee better retention of this important carotenoid.  相似文献   

6.
Leaves of Lycium barbarum are widely used as medicine vegetables and functional tea in China. The main flavonoids present in the leaves were separated and identified by high performance liquid chromatography (HPLC), liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (LC-(APCI) MS) and ultraviolet-visible spectra with shift additives. The predominant flavonoid was identified as rutin. Leaves are the rutin-rich parts (16.03–16.33 mg/g). In the wild and cultivated L. barbarum fruits, contents of rutin were determined very low (0.09–1.38 mg/g). The contents of total flavonoids (21.25 mg/g) of cultivated L. barbarum leaves were much higher than those in the wild L. barbarum leaves (17.86 mg/g), so cultivated barbarum leaves are a suitable source for medicine vegetables and functional tea.  相似文献   

7.
The search for natural antioxidants, especially of plant origin, has notably increased in recent years. Bunium persicum Boiss. is an economically important medicinal plant growing wild in the dry temperature regions in Iran. In this study, chemical constituents of the essential oil of the seed from Bunium persicum Boiss. have been studied by GC/MS technique. The major components were caryophyllene (27.81%), gamma-terpinene (15.19%), cuminyl acetate (14.67%). Individual antioxidant assays such as, DPPH* scavenging activity and beta-carotene bleaching have been carried out. In DPPH* system, the EC(50) value of essential oil was determined as 0.88 mg/mL. In beta-carotene bleaching antioxidant activity of essential oil (0.45%) was almost equal to BHT at 0.01%. In addition, the antioxidant activity of the essential oil was evaluated in crude soybean oil by monitoring peroxide and thiobarbituric acid values of the oil substrate. The results showed that the Bunium persicum essential oil (BPEO) was able to reduce the oxidation rate of the soybean oil in the accelerated condition at 60 degrees C (oven test). The essential oil at 0.06% showed the same effect of BHA at 0.02%. Hence, BPEO could be used as an additive in food after screening.  相似文献   

8.
This work was carried out to investigate the pulp composition of four mango cultivars (Haden, Tommy Atkins and Ubá) at the ripening stage in relation to three components with antioxidant potential (total phenolics, carotenoids and ascorbic acid). Total phenolic compound content was estimated by the Folin-Ciocalteu reagent and total carotenoid content by spectrophotometry at 450 nm. The contents of β-carotene and total vitamin C (ascorbic acid and dehydroascorbic acid) were quantified by high performance liquid chromatography. Differences were found among the four mango cultivars in all the components analyzed. The content of phenolic compounds ranged from 48.40 (Haden) to 208.70 mg/100 g (Ubá); total carotenoid from 1.91 (Haden) to 2.63 mg/100 g (Palmer); β-carotene from 661.27 (Palmer) to 2,220 μg/100 g (Ubá) and total ascorbic acid ranged from 9.79 (Tommy Atkins) to 77.71 mg/100 g (Ubá). These results corroborated previous information that mangoes are a good source of antioxidants in human diet.  相似文献   

9.
Plants constitute an alternative source of proteins in the human diet, with advantages over animal proteins because of their low content of saturated fats and absence of cholesterol. Within the framework of a wider research project on the role of Amaranthus cruentus (Ac) in lipid metabolism, in this work the chemical composition and biological value of the Ac flour and its protein concentrate were compared. Proximate chemical composition, amino acid and fatty acid profiles, some antinutrient factors, and biological values were determined for Ac seed flour and its protein concentrate obtained by extraction at pH 11 and precipitation at pH 4.5. The flour protein content was 16.6 g% while that of the concentrate was 52.56 g%. The content of the soluble dietary fiber with a hypolipemic function was notably higher in the protein concentrate (12.90 g%) than in the seed flour (4.29 g%). The protein concentrate also exhibited a higher content of insoluble dietary fiber. The Ac flour and the concentrate contain 75.44 and 56.95% unsaturated fatty acids, respectively. Squalene, which affects the biosynthesis of cholesterol, was detected both in the flour and the concentrate oils, with a higher content in the concentrate (9.53%) as compared to the flour (6.23%). Comparison of the amino acid composition with the FAO pattern protein indicated that the concentrate does not have limiting amino acids, while the flour has leucine, threonine, and valine. The content of lysine was high in both the flour and the concentrate, making these products particularly useful as a complement for cereal flour, which is deficient in this amino acid. The biological quality analysis demonstrated an improvement in the quality of the concentrate. The presence of saponins, phytic acid, and trypsin inhibitors in the concentrate, which favor the metabolism of lipids, suggests that consumption of the concentrate might reduce the risk of heart disease.  相似文献   

10.
The hydro-alcoholic extracts of five Equisetum species, E. arvense L., E. sylvaticum L., E. fluviatile L., E. palustre L. and E. telmateia Ehrh., growing-wild in Serbia were evaluated for their genotoxicity, antimicrobial activity, antioxidant capacity and the results related to the total phenol content and HPLC flavonoid profiles. The total phenol content was 92–349 μmol expressed as equivalents of chlorogenic acid per g of dried plant material. Main identified compounds were kaempferol-, quercetin- glycosides and caffeic acid derivatives. E. telmateia extract showed the greatest antioxidant capacity. Almost all tested microorganisms demonstrated some degree of sensitivity to the examined extracts. All tested extracts at 62.5 μg/ml showed higher incidence of micronucleus formation than in the control sample. The obtained data allowed mutual comparison of examined species and their assessment as possible sources of antioxidants, antimicrobials and/or genotoxic substances.  相似文献   

11.
Edible fruits of the native South American tree Melicoccus bijugatus Jacq. are consumed fresh or in traditional food, drink and medicinal preparations. Some therapeutic effects of these fruits may be due to phenolics and sugars. Aqueous acetone, methanol or ethanol tissue extracts of different cultivars or collections of M. bijugatus fruits from the Dominican Republic and Florida were analyzed for total phenolics and free radical scavenging activity by UV-vis spectroscopy, sugars by gas chromatography, and antimicrobial activity by the disc diffusion assay. Total phenolics and free radical scavenging activities ranked: seed coat > embryo > pulp extracts. Montgomery cultivar fruits had the highest total phenolics. For sugars: pulp > embryo and highest in Punta Cana fruit pulp. In all extracts: sucrose > glucose and fructose. Glucose:fructose ratios were 1:1 (pulp) and 0.2:1 (embryo). Pulp extracts had dose-response antibacterial activity and pulp and embryo extracts had antifungal activity against one yeast species. Phenolics and sugars were confirmed with thin-layer chromatography and nuclear magnetic resonance. Sugar-free pulp fractions containing phenolics had slightly more antimicrobial activity than H2O-soluble pulp fractions with sugars. Results indicate M. bijugatus fruits contain phenolics, sugars and other H2O-soluble compounds consistent with therapeutic uses. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

12.
Protein isolates from L. campestris and soybean seeds were prepared using isoelectric precipitation (PI) and micellization (MI) procedures. The amount of protein recovered was considerably higher with the isoelectric precipitation than with the micellization procedure (60% and 30%, respectively). Protein contents were higher than 90% in protein isolates. Antinutritional factors content (alkaloids, lectins, and tannins) were reduced to innocuous levels after protein isolate preparation. Minimum protein solubility for the precipitated lupin protein isolate (LPI) was at pH 4.0, and between pH 4 and 6 for the micellized lupin protein isolate (LMI), increasing at both extremes of the pH scale. Water absorption for the LMI was 1.3 ml/g of protein and its oil absorption 2.2 ml/g of protein. The LPI had 1.7 ml/g of protein in both water and oil absorption. Foaming capacity and stability was pH-dependent. Foaming capacity was higher at pH 2 and lower near the protein isoelectric points. Minimum protein concentration for gelation in LMI was 8% w/v at pH 4, while for LPI was 6% at pH 4 and 6. Amino acid composition in L. campestris flour and protein isolates was high in lysine and low in methionine. Most of the essential amino acids in lupin protein isolates were at acceptable levels compared to a reference pattern for infants and adults. The electrophoretic pattern of both protein isolates showed three bands with different mobilities, suggesting that the protein fractions belong to alpha-conglutin (11S-like protein), beta-conglutin (7S-like protein) and gamma-conglutin. It is proven that some of the functional properties of L. campestris protein isolates are similar to those soybean protein isolates recovered under equal conditions.  相似文献   

13.
Aronia melanocrpa fruit juice (AMFJ) used in our experiment was very rich in phenolic substances (709.3 mg gallic acid equivalents/100 ml juice). Anthocyanins (106.8 mg cyanidin-3-glucoside equivalents/100 ml juice) were the main flavonoid group. The aim of this study was to assess the influence of AMFJ on plasma lipids and lipoprotein profile, and histopathology of liver and aorta in rats with dietary-induced hyperlipidemia. AMFJ was administered by gavage for 30 days at doses of 5, 10 and 20 ml/kg body weight to rats fed a standard diet (SD) or a 4% cholesterol-containing diet (4% ChD). The 4% ChD caused a significant elevation of plasma total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and triglycerides (TG). AMFJ did not significantly influence plasma lipids in rats fed the SD and significantly hindered the elevation of plasma TC, LDL-C and TG in rats fed the 4% ChD. High-density lipoprotein cholesterol (HDL-C) levels were not significantly influenced either by the 4% ChD or by AMFJ. Neither the cholesterol feeding, nor AMFJ treatment induced any histopathological changes in rat liver and aorta. In conclusion, AMFJ showed an antihyperlipidemic effect in rats with hyperlipidemia and could be valuable in reducing this factor of cardiovascular risk.  相似文献   

14.
Serotonin N-hydroxycinnamoyltransferase (SHT) is a key enzyme in the synthesis of feruloylserotonin (FS) and 4-coumaroylserotonin (CS). These serotonin derivatives show strong antioxidant activity, making them valuable for both nutritional and pharmacological use in humans. Ectopic expression of SHT under the control of the endosperm specific-glutelin and prolamin promoters from rice was produced via Agrobacterium-mediated transformation. SHT expression was confirmed by Southern blot analysis, followed by Northern blotting and SHT enzyme activity analyses using total RNA and protein, respectively, extracted from transgenic seeds. The glutelin A3 (GluA3) promoter produced low SHT mRNA expression in rice seeds, whereas the prolamin promoter expressed high levels of SHT mRNA. In spite of the ectopic expression of SHT in rice seeds, both transgenic genotypes accumulated levels of serotonin derivatives similar to those found in wild-type rice. Furthermore, our data suggest that serotonin, rather than phenylpropanid-CoAs, is the rate-limiting substrate in the biosynthesis of serotonin derivatives in SHT-overexpressing transgenic rice seeds.  相似文献   

15.
A natural colorant was extracted fromCassia tora L. using buffer solutions (pH: 2–11) as extractants. The dyeing solution (Cassia tora L. extract) extracted using pH 9 buffer solution was found to give the highest K/S values of dyed fabrics. Cotton and silk fabrics were dyed withCassia tora L. extract at 60°C for 60 min with pre-treatment of various metal salts as mordants. It was found thatCassia tora L. extract was polygenetic dyestuffs and its major components were anthraquinones. Studies have been made on the effects of the kind of mordant on dyeing properties and colour fastnesses of cotton and silk fabrics. The K/S of cotton fabrics increased in the order of the dyeing using FeSO4>CuSO4>ZnSO4>MnSO4≅Al2(SO4)3>NiSO4>none, however, the K/S of silk fabrics increased in the order of the dyeing using FeSO4>CuSO4>ZnSO4≅Al2(SO4)3>MnSO4≅NiSO4>none. It was found that the K/S values of dyed fabrics were largely affected by the colour difference (ΔE) between mordanted fabric and control fabric. However, they were not depended on the content of mordanted metal ion of the fabrics. Mordants FeSO4 and CuSO4 for cotton fabric, FeSO4, CuSO4, and Al2(SO4)3 for silk fabric were found to give good light fastness (rating 4).  相似文献   

16.
Turmeric extracts, among which curcumin and bis-demethoxycurcumin, are by far known for their therapeutic activities. In this study we propose easy and low cost synthetic pathways in order to obtain glucosyl-curcuminoids, safe and water soluble potential drugs and dyes, which may be implied in different fields ranging from pharmacology to food chemistry. The complete 1H and 13C NMR characterization of naturally occurring curcumin, bis-demethoxycurcumin and new synthetic glucosyl-curcuminoids is reported.  相似文献   

17.
Total antioxidant capacities, 2,2-diphenyl-1-picrylhydrazyl (DPPH·), hydroxyl (HO·), scavenging activities, and total phenolic values were determined in extracts of Cucurbita pepo L. female and male flowers. Powdered C. pepo L. samples were extracted in aqueous ethyl acetate (EA: W1, 17:3), ethanol (E), and water (W) by agitating in magnetic stirrer for 80°C, 15 min and also by in aqueous ethyl acetate (EA: W2, 17:3) at 25°C, 15 min. DPPH·, HO· scavenging capacities and total phenolic values of C. pepo L. female and male were higher in EA:W2 than in other extracts. In addition, all determined antioxidant capacities of female were significantly higher than male.  相似文献   

18.
Three marketing varieties of almonds; Carmel, Mission, and Nonpareil; were analyzed for proximate composition and protein nutritive quality. Moisture, lipids, protein, ash, sugars, and tannins ranges were 3.05-4.33%, 43.37-47.50%, 20.68-23.30%, 3.74-4.56%, 5.35-7.45%, and 0.12-0.18%, respectively. No detectable hemagglutinating and trypsin inhibitory activities were present in Carmel, Mission, and Nonpareil almonds. Amino acid analyses indicated the sulfur amino acids (methionine + cysteine), lysine, and threonine to be the first, second, and third limiting amino acids in almonds when compared to the recommended amino acid pattern for children 2-5-year old. However, compared to the recommended amino acid pattern for adults, sulfur amino acids were the only limiting amino acids in almonds tested. True Protein Digestibility (% TPD) values for Carmel, Mission, and Nonpareil were 88.55 +/- 1.26, 92.25 +/- 1.05, and 82.62 +/- 1.47, respectively. Protein Digestibility Corrected Amino Acid Scoring (PDCAAS) values suggested almond proteins to be of poor nutritional quality.  相似文献   

19.
Potato is an important crop, grown worldwide. It suffers from many pests and diseases among which late blight, caused by the oomycete Phytophthora infestans, is the worst. The disease is still causing major damage in many potato production areas and control is only possible by applying fungicides frequently. The knowledge on the molecular biology and genetics of the interaction between the plant and the oomycete is developing rapidly. These are relevant fields of study, currently dominated by the discovery of many resistance genes and numerous effector proteins and the analysis of their specific mode of action. These studies may yield essential information needed for the development of durable resistance. The long-term and worldwide effort to breed for resistance so far has had little effect. A novel breeding approach may change this. It is based on cisgenic modification (CM) consisting of marker-free pyramiding of several resistance genes and their spatial and temporal deployment yielding dynamic varieties that contain potato genes only. It is envisioned that this CM approach with potato’s own genes will not only prove societally acceptable but may also result in simplifications in the legislation on use of the CM approach. Various parties in the potato research arena intend to cooperate in this novel approach in a number of developing countries where potato substantially contributes to food security. The use of resources such as land, water and energy improves when the effect of late blight is markedly reduced.  相似文献   

20.
Millingtonia hortensis is a medicinal plant widely used in many Asian countries. An aqueous crude extract of this plant has been shown the apoptosis induction on RKO colon cancer cells. However, its mechanism remains unknown. To learn more about this plant extract, we partially purified the crude extract using Sephadex LH-20 and three aqueous fractions were collected. Each fraction was investigated for cytotoxicity using MTT assay. Fraction 1 showed antiproliferative effect on RKO cells with dose-dependent manner, while fraction 2 and 3 had no effect. Induction of apoptosis was determined using flow cytometry and DNA fragmentation method. Apoptotic cell numbers and the appearance of fragmented DNA increased with dose-dependent manner after treatment with fraction 1 for 48 h. We further investigated the expression of apoptotic protein by western blot analysis. Fraction 1 decreased the expression of anti-apoptotic protein, Bcl-xL and p-Bad, while pro-apoptotic protein Bad, was not changed. Fraction 1 also decreased the expression of p-Akt and slightly increased the level of total Akt. These results indicated that fraction 1 is able to inhibit cell proliferation and induce apoptosis on RKO cells by decreasing the expression of Bcl-xL, p-Bad and p-Akt which are involving in survival of cancer cells.  相似文献   

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