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1.
The antioxidative effects of vegetables are expected to prevent carcinogenesis. The intake of daikon sprout (Japanese name “kaiware-daikon”, Raphanus sativus L.) or ginger (Zingiber officinale Roscoe) significantly decreased the concentration of urinary thiobarbituric acid-reactive substances (TBARS) in rats as compared with those before the intake. Moreover, the intake of these vegetables reduced urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG) levels in lipopolysaccharide (LPS)-treated rats as compared with those fed a basal diet only. These results show that these vegetables suppress lipid peroxidation and the formation of malonaldehyde, and protect DNA from LPS-induced oxidative damage in rats. The suppression of lipid peroxidation and oxidative DNA damage in rats by the intake of daikon sprout or ginger indicates that these vegetables have an antioxidative effect in vivo which could be related to the prevention of carcinogenesis.  相似文献   

2.
In this study, a novel high performance thin layer chromatography (HPTLC) technique for fingerprinting of Jamaican ginger was developed and its application to the chemo-profiling of four cultivars of Jamaican ginger illustrated. Applications of the method to maturation and storage studies involving ginger oleoresins are also presented. The method showed good resolution of the pungent compounds characteristic of ginger: 6-gingerol, 8-gingerol, 10-gingerol and 6-shogaol, with five other discrete zones being described as additional references. HPTLC fingerprints of the ginger cultivars showed chemical homogeneity with small qualitatively observed differences in the intensities of the gingerol and shogaol zones. Quantification of these compounds by high-performance liquid chromatography (HPLC) revealed significant differences in total pungency among the cultivars. Essential oil yields from the cultivars also varied significantly. The described characterisations will prove useful in the authentication of Jamaican ginger.  相似文献   

3.
4.
A novel method for purifying gingerols from ginger was developed using a high-speed counter-current chromatography (HSCCC). The two-phase solvent system such as light petroleum (bp 60–90 °C)–ethyl acetate–methanol–water (5:5:6.5:3.5, v/v/v/v) was applied to the separation and purification of 6-, 8- and 10-gingerol from a crude extract of ginger. The experiment yielded 30.2 mg of 6-gingerol, 40.5 mg of 8-gingerol, 50.5 mg of 10-gingerol from 200 mg of crude extract in one-step separation. And the purity of these compounds was 99.9%, 99.9% and 99.2%, respectively, as determined by high-performance liquid chromatography (HPLC). Their structures were identified by gas chromatography–mass spectrometry (GC/MS) and 1H, 13C nuclear magnetic resonance (NMR).  相似文献   

5.
Following an initial clean-up step on silica column, high-speed counter-current chromatography (HSCCC) was used to purify gingerols from an extract of the dried rhizome of Zingiber officinale. The sample was separated with petroleum ether–ethyl acetate–methanol–water (1:0.2:0.5:0.7, v/v) and petroleum ether–ethyl acetate–methanol–water (1:0.2:0.7:0.5, v/v) in a stepwise elution and yielded 132 mg of 6-gingerol, 31 mg of 8-gingerol and 61 mg of 10-gingerol from 360 mg of pre-purified sample. The purity of each compound was over 98% as determined by HPLC. The structures of the three compounds have been identified by LC-ESI-MS, 1H NMR and 13C NMR.  相似文献   

6.
Inhibitors of cell adhesion molecule-mediated cell adhesion might be novel therapeutic agents for the treatment of various inflammatory diseases. In this study, nine phenolic compounds were isolated from the methanol extracts of Zingiber officinale roots by bioactivity-guided fractionation. The structures of the compounds were determined by spectroscopic analysis (1H, 13C NMR and MS), to be 6-gingerol (1), 8-gingerol (2), 10-gingerol (3), 6-shogaol (4), 8-shogaol (5), 10-shogaol (6), dehydro-6-gingerdione (7), dehydro-10-gingerdione (8) and 6-paradol (9). Compounds 3, 4, 5 and 7 inhibited direct binding between sICAM-1 and LFA-1 of the THP-1 cells in a dose-dependent manner with IC50 values of 57.6, 27.1, 65.4 and 62.0 μM, respectively. Compounds 4 and 7 had an inhibitory effect on direct binding between sVCAM-1 and VLA-4 of THP-1 cells. These results suggest that the phenolic compounds from Z. officinale roots are good candidates for therapeutic strategies aimed at inflammation.  相似文献   

7.
The essential oils obtained by hydrodistilation of the leaves and rhizomes of Zingiber officinale var. rubrum Theilade were analysed by capillary GC and GC–MS. Forty-six constituents were identified in the leaf oil, while 54 were identified in the oil from the rhizomes. The leaf oil was clearly dominated by β-caryophyllene (31.7%), while the oil from the rhizomes was predominantly monoterpenoid, with camphene (14.5%), geranial (14.3%), and geranyl acetate (13.7%) the three most abundant constituents. The evaluation of antibacterial activities using the micro-dilution technique revealed that both the leaf and rhizome oils were moderately active against the Gram-positive bacteria Bacilluslicheniformis, Bacillus spizizenii and Staphylococcus aureus, and the Gram-negative bacteria Escherichia coli, Klebsiella pneumoniae and Pseudomonas stutzeri.  相似文献   

8.
Ginger, a medicinal herb with bioactive components, is now widely used. This study reports the information of bioactive components in two varieties ginger root (Zingiber officinale Roscoe), Guangdong-ginger (GG) and Chu-ginger (CG) available in Taiwan and compares their bioactive components and antioxidant properties using aqueous and ethanolic extract. The proximate analysis of both ginger rhizomes gave similar profiles. Total contents of organic acids were 37.33 and 91.06 mg/g dry weight for GG and CG, respectively, with oxalic and tartaric acids being two major acids. HPLC analysis revealed gingerols and shogaol in both ginger were similar but curcumin content was higher in GG. The essential oils exhibited similar volatile profiles and 60 and 65 compounds were identified for GG and CG, respectively. Among the essential oils major components were camphene, sabinene, α-curcumene, zingiberene, α-farnesene, β-sesquiphellandrene, neral, and geranial. The antioxidant effect of ginger ethanolic extracts were more effective than aqueous extracts in Trolox equivalent antioxidant capacity and Ferric reducing ability of plasma. Contrarily, ginger aqueous extracts were more effective in free radical scavenging activities and chelating abilities. Based on the results, two ginger rhizomes exerted protective effects and could be used as a flavouring agent and a natural antioxidant.  相似文献   

9.
The present work aims at identifying enzymatic activities that may contribute to the post-mortem autolysis of the ventral muscle, known as belly bursting, in herring (Clupea harengus). Gelatinolytic proteases extracted from several herring tissues and also from a sardine (Sardina pilchardus) tissue were partially characterised using gelatin zymography, inhibitor analysis, immunodetection with anti-trypsin antibody and MALDI-TOF/TOF peptide sequencing. The results indicate the presence of gelatinolytic trypsin-like serine proteases and metalloproteases in several samples including the ventral muscle of herring. MS/MS analysis gave partial sequences of peptides from some of the proteases, and these were identified as elastase, trypsin and aspartyl aminopeptidase. It is likely that belly bursting in herring is caused by leakage of enzyme-rich fluids from the intestine and/or pyloric caeca which may also contain exogenous proteases from the digestive systems of the prey.  相似文献   

10.
This paper presents the centesimal and mineral composition, fatty acid profile of the lipidic fraction, phenolic and anthocyanin contents, and antioxidant activity of Gaylussacia brasiliensis fruit. The results indicated the following composition: moisture (81.30%), lipids (0.62%), proteins (0.56%), carbohydrates (10.74%), dietary fiber (6.53%), and ash (0.25%). The main elements comprising the mineral composition were K, Mg, Ca, and Fe. The fatty acid composition was characterized by a high content of polyunsaturated fatty acids (62.2%) and a high PUFA/SFA ratio (2.92). The G. brasiliensis fruit contained considerable amounts of phenolics (492.87 mgAG/100 g) and anthocyanins (240.43 mg/100 g), which contribute to its high antioxidant activity. This study highlights the potential of this fruit as an important source of both nutritional and bioactive compounds available in the native Brazilian flora.  相似文献   

11.
The sour orange (Citrus aurantium) juice is commonly used as flavoring and acidifying agent for vegetable salads and appetizers in Turkey. It was aimed to determine the survival and growth pattern of Salmonella Typhimurium and Listeria monocytogenes in sour orange juice. Different concentrations of neutralized and un-neutralized juice samples were inoculated with each of the test microorganisms (∼6 log CFU/mL) separately and then incubated at 4 °C and 37 °C for seven days. It was detected both of the test microorganisms could survive and even grow in neutralized juice samples at 37 °C for two days. However, none of them could survive at the end of seventh day of incubation at 37 °C. Low incubation temperature (+4 °C) increased the survival of the tested microorganisms. Also, it was detected that L. monocytogenes were less resistant to the variable conditions than S. Typhimurium. It was concluded that the antimicrobial effect of sour orange juice mainly depends on the low pH value of the product. However, incubation time and temperature are also effective on the survival of the tested pathogens.  相似文献   

12.
High performance liquid chromatography (HPLC) was used to characterise phenolic profile and to select the most effective anti-browning compound(s) on fresh lettuce. Four anti-browning agents, ascorbic acid, cysteine, citric acid and oxalic acid were tested for their effectiveness on preventing loss of phenolic compounds in lettuce during processing and storage. Aliquots of the reaction mixture were withdrawn at different times varying from 0 to 24 h, and directly analysed by HPLC. Protocatechuic acid, chlorogenic acid, ferulic acid, caffeic acid, p-coumaric acid and phloridzin were identified in fresh lettuce. Degradation of phenolic compounds followed a first-order kinetic pattern. The effect of anti-browning agents on first-order degradation rates of phenolic compounds was determined. Lettuce treated with oxalic acid and ascorbic acid maintained a higher level of phenolic compounds than citric acid and cysteine. Interestingly, cysteine had no positive effect for the prevention of oxidation of phenolic compounds even though it prevented browning in lettuce.  相似文献   

13.
The in vitro kinetics of lettuce PPO with respect to dissolved oxygen using catechin, chlorogenic acid, caffeic acid and gallic acid has been examined. In-vitro lettuce polyphenol oxidase (PPO) activity was determined by measuring the consumption of oxygen during the oxidation reaction. The effect of whey protein concentrate (WPC) was tested on the inhibition of lettuce PPO comparing with ascorbic acid (AA) and cysteine. A competitive model that considered inhibitors was the most appropriate model to explain reaction kinetics. Browning of lettuce was also monitored during storage for 24 h. Addition of WPC prevented loss of lightness in lettuce. Loss of identified phenolic compounds in lettuce was measured during the enzymatic browning process by high-performance liquid chromatography. Degradation of identified phenolic compounds followed first order kinetics during storage. Combination of WPC with cysteine was proposed for the protection of phenolics compounds against PPO-catalysed oxidation.  相似文献   

14.
The biomonitor technique was investigated as a rapid and automatic method for measuring the resistance of cowpea varieties to the seed beetle Callosobruchus maculatus. This technique measures the activity of internally feeding insect larvae by counting ultrasonic emissions produced as they feed. Activity throughout the development of C. maculatus larvae in known susceptible and resistant cowpea varieties was recorded. This showed details of the development of each larval instar, and showed clear differences between the resistant and susceptible cowpeas. A rapid method for comparing cowpeas was proposed in which the activity of larvae was recorded for 24 h starting 14 days after oviposition. Using this method, significant differences in activity were apparent between one susceptible and two resistant cowpea varieties. Further comparisons using a randomised block experimental design also showed a clear difference in activity between one susceptible and one known resistant cowpea variety. This experimental protocol took 21 days. It is suggested that the biomonitor offers a promising method for screening seeds for resistance to insect pests with a reduction in the time and effort required over conventional bioassay methods.  相似文献   

15.
Scallop (Patinopecten yessoensis) and abalone (Haliotis discus hannai Ino) muscle were hydrolysed with commercially available food-grade proteases. The resulting hydrolysates showed DPPH and hydroxyl radicals scavenging abilities, reducing power, and ferrous ion chelating capacity. The antioxidant activities of hydrolysate of abalone foot muscle (HAFM) increased with increasing incubation time during the whole hydrolysis process in 180 min. Whereas, the antioxidant activities of hydrolysate of scallop adductor muscle (HSAM) increased at initial stage and peaked after 25-30 min of hydrolysis, and then gradually decreased thereafter. Compared with HAFM, HSAM with comparable hydrolysis time contained more free amino acids (FAA) and small-sized peptides (below 500 Da), which may account for the differences in antioxidant activities versus hydrolysis time curves of the two hydrolysates. The above results indicate that limited hydrolysis of proteins can increase their antioxidant activity, whereas extensive hydrolysis can decrease it.  相似文献   

16.
A monomeric protein with molecular mass of ∼35 kDa, isolated from Murraya Koenigii L. (curry leaves) shows potent antibacterial activity. The protein designated as APC (antioxidant protein from curry leaves) demonstrated potent antibacterial activity against all the human pathogenic strains tested. APC effectively inhibited Escherichia coli, Staphylococcus aureus, Vibrio cholerae, Klebsiella pneumoniae, Salmonella typhi and Bacillus subtilis. The inhibition is comparable to that of commercial antibiotics chloramphenicol, streptomycin and gentamycin. APC inhibited bacterial growth, with MIC values ranging from 13 to 24 μg/ml, which are comparable to MIC values of standard antibiotics. APC is devoid of ribonuclease/deoxyribonuclease and protease activity. APC is non-toxic at tested doses. These results encourage further studies of APC as a potent therapeutic agent.  相似文献   

17.
The previously reported genetic polymorphisms of the stearoyl-CoA desaturase (SCD1) and sterol regulatory element binding protein-1 (SREBP-1) genes were investigated in Fleckvieh bulls using the PCR-RFLP and AS-PCR methods, respectively. The genomic DNA was obtained from a total of 370 bulls. The frequencies of alleles A and V of the single nucleotide polymorphism in exon 5 of the SCD1 gene (SNP 878C>T) were 0.555 and 0.445, respectively. In the 84-bp Ins/Del polymorphism in intron 5 of the SREBP-1 gene, the frequency of the L allele (insertion) was markedly higher (0.920) than that of the S allele (deletion; 0.080). Fatty acid profile was determined in a total of 367 samples of muscle fat (MSF) and 150 samples of subcutaneous fat (SCF). The AA genotype of SCD1 polymorphism showed a lower content of C18:0 (P < 0.01) and higher contents of C14:1 cis-9 (P < 0.001) and C18:1 cis-9 (P < 0.05) in MSF compared to the VV genotype. As a result, the bulls with genotypes AA or AV had lower SFA (P < 0.01), higher MUFA (P < 0.05) and higher MUFA/SFA (P < 0.01) than VV animals. The results obtained for SCF were similar. The SREBP-1 polymorphism was associated with a higher content of C14:1 cis-9 (P < 0.01) in the LS compared to LL genotype in SCF. The results of this study demonstrated the existence of the polymorphisms in the SCD1 and SREBP-1 genes in the population of Fleckvieh cattle and their associations with the concentrations of several MSF and SCF fatty acids.  相似文献   

18.
Almond fruit consists of three or correctly four portions: kernel or meat, middle shell, outer green shell cover or almond hull and a thin leathery layer known as brown skin of meat or seedcoat. The nutritional importance of almond fruit is related to its kernel. Other parts of fruit such as shells and hulls were used as livestock feed and burned as fuel. In the past decades, different phenolic compounds were characterised and identified in almond seed extract and its skin, shell and hull as almond by-products. In addition, polyphenols are abundant micronutrients in the human diet, and evidence for their role in the prevention of degenerative diseases such as cancer and cardiovascular diseases is emerging. The health effects of polyphenols depend on the amount consumed and on their bioavailability. In this contribution, various phenolic compounds present in almond and its by-products, their antioxidant properties and potential use as natural dietary antioxidant, as well as their other beneficial compounds and applications are reviewed.  相似文献   

19.
Antioxidant activity and composition of essential oil and extracts of Rhizoma Homalomenae were determined. The extracts, especially the ethyl acetate extract (QJ4 fraction) of the aqueous residue after oil distillation, had considerable antioxidant potency which was significantly associated with their total phenolic and flavonoid contents, but the essential oil showed only weak or moderate activity. GC–MS analysis of the essential oil (yield: 0.82%, v/w) resulted in the identification of 77 compounds, accounting for 96.5% of the content of the oil. The major components, epi-α-cadinol (14.8%), α-cadinol (14.8%), α-terpineol (13.8%), linalool (11.1%), terpinen-4-ol (4.92%), and δ-cadinene (4.91%) constituted 64.3% of it. LC–MS/MS and HPLC analyses showed seven phenolic compounds (protocatechuic acid, vanillic acid, syringic acid, caffeic acid, p-coumaric acid, ferulic acid and apigenin) with a great amount in the ethyl acetate extract (QJ4 fraction). The strong antioxidant properties of the plant extracts may be attributed to the presence of these phenolics.  相似文献   

20.
Fumigant toxicity of essential oils from rhizomes of Alpinia conchigera, Zingiber zerumbet, Curcuma zedoaria and their major compounds; camphene, camphor, 1,8-cineole, α-humulene, isoborneol, α-pinene, β-pinene and terpinen-4-ol was investigated with adults of Sitophilus zeamais, Tribolium castaneum, Anisopteromalus calandrae and Trichogramma deion larvae. The last two insects are parasitoids commonly used to control stored-product weevils and moths. The trial was evaluated at 0, 37, 74, 148, 296, 444, 593 μL/L in air after 12, 24 and 48 h for S. zeamais, T. castaneum and A. calandrae, and 24 h for T. deion. Alpinia conchigera oils were toxic to S. zeamais, T. castaneum and T. deion, while the other two plant oils had low toxicity. Adults of S. zeamais and T. castaneum were more susceptible to A. conchigera oils than their eggs, larvae or pupae. Sitophilus zeamais adults (LC50 85 μL/L in air) were slightly more tolerant of A. conchigera oils than T. castaneum (LC50 73 μL/L in air) after 48 h exposure. Synthetic essential oils, a mixture of pure compounds in the same ratios of the extracted essential oils, were tested with S. zeamais and T. castaneum adults. Synthetic essential oils were more toxic than the extracted essential oils to both insects. Zingiber zerumbet oils (LC50 26 μL/L in air) and C. zedoaria oils (LC50 25 μL/L in air) were significantly more toxic to adults of A. calandrae than A. conchigera oils (LC50 37 μL/L in air) whereas T. deion larvae were more sensitive to A. conchigera oils (LC50 62 μL/L in air) than Z. zerumbet and C. zedoaria oils (LC50 > 593 μL/L in air). Tribolium castaneum was more susceptible than S. zeamais to the eight pure compounds. Terpinen-4-ol was highly toxic to both insects.  相似文献   

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