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1.
BACKGROUND: Medicinal plants have been used to treat various diseases since ancient times. Their specific activities, such as antioxidant, anti‐inflammatory and anti‐cancer, have been studied intensively. In particular, plants grown in Vietnam have attracted considerable attention among food chemists as ideal sources of natural medicinal chemicals. RESULTS: The methanol extracts from three edible Vietnamese‐grown plants, Tram, Voi and Gac, tested with the DPPH assay showed antioxidant activities of 91.7 ± 0.4, 63.4 ± 0.7 and 3.7 ± 0.1% respectively. The malonaldehyde/gas chromatography assay also revealed strong antioxidant activity in Tram and Voi at a level of 25 µg mL?1 (95.5 ± 0.3 and 78.5 ± 1.4% respectively). These results were confirmed by the thiobarbituric acid assay. The antioxidant activities correlated positively with the level of total phenolics in all plants. Tram exhibited dose response‐related lipoxygenase‐inhibitory activity, with values of 74.2 ± 3.1% at 5 µg mL?1, 62.0 ± 0% at 0.5 µg mL?1 and 3.0 ± 1.5% at 0.05 µg mL?1. Conversely, Voi and Gac showed negative anti‐lipoxygenase activity. CONCLUSION: The antioxidant/anti‐inflammatory activities and total phenolic contents of the three edible plants grown in Vietnam revealed that they are good sources of supplements for human health. Copyright © 2011 Society of Chemical Industry  相似文献   

2.
BACKGROUND: Jellyfish collagen was hydrolysed with trypsin and properase E, and jellyfish collagen peptide (JCP) was purified from the enzymatic hydrolysate using ion exchange chromatography and gel filtration. The antioxidant activity of JCP in a linoleic acid emulsion system, its superoxide anion‐ and hydroxyl radical‐scavenging activities and its copper‐chelating ability were evaluated in vitro. Initial investigations of JCP's ability to inhibit melanogenesis were carried out using cultured B16 melanoma cells. RESULTS: The molecular weight distribution of JCP was from 400 to 1200 Da. Amino acid analysis showed that JCP was rich in Gly, Pro, Ser, Ala, Glu and Asp and had a total hydrophobic amino acid content of 384.2 g kg?1. JCP showed high antioxidant activity (IC50147.8 µg mL?1), superoxide anion‐scavenging activity (IC5021.9 µg mL?1), hydroxyl radical‐scavenging activity (IC5016.7 µg mL?1) and copper‐chelating ability (IC5088.7 µg mL?1) in vitro. It also significantly inhibited intracellular tyrosinase activity, decreased melanin content and enhanced glutathione synthesis (P < 0.05). Furthermore, JCP decreased intracellular cAMP levels and suppressed tyrosinase mRNA expression. CONCLUSION: Based on the results of this study, JCP exerts anti‐melanogenic actions via its antioxidant properties and copper‐chelating ability. JCP could be used as a natural skin‐lightening agent in the medicine and food industries. Copyright © 2009 Society of Chemical Industry  相似文献   

3.
Syzygium cumini, widely known as Jamun, is a tropical tree that yields purple ovoid fleshy fruit. Its seed has traditionally been used in India for the treatment of diabetes. Based on the available ethno‐pharmacological knowledge, further studies were extended to understand the chemical composition and antioxidant activities of three anatomically distinct parts of fruit: the pulp, kernel and seed coat. Fruit parts, their corresponding ethanol extracts and residues were evaluated for chemical composition. The alcoholic extract was evaluated for its antioxidant potential against DPPH?, OH?, O2?? and lipid peroxidation. The whole fruit consisted of 666.0 ± 111.0 g kg?1 pulp, 290.0 ± 40.0 g kg?1 kernel and 50.0 ± 15.0 g kg?1 seed coat. Fresh pulp was rich in carbohydrates, protein and minerals. Total fatty matter was not significant in all three parts of fruit. Detailed mineral analysis showed calcium was abundant in all fruit parts and extracts. Total phenolics, anthocyanins and flavonoid contents of pulp were 3.9 ± 0.5, 1.34 ± 0.2 and 0.07 ± 0.04 g kg?1, respectively. Kernel and seed coat contained 9.0 ± 0.7 and 8.1 ± 0.8 g kg?1 total phenolics respectively. Jamun pulp ethanol extract (PEE), kernel ethanol extract (KEE) and seed coat ethanol extract (SCEE) showed a high degree of phenolic enrichment. DPPH radical scavenging activity of the samples and standards in descending order was: gallic acid > quercetin > Trolox > KEE > BHT > SCEE > PEE. Superoxide radical scavenging activity (IC50) of KEE was six times higher (85.0 ± 5.0 µg mL?1) compared to Trolox (540.0 ± 5.0 µg mL?1) and three times compared to catechin (296.0 ± 11.0 µg mL?1). Hydroxyl radical scavenging activity (IC50) of KEE was 151.0 ± 5.0 µg mL?1 which was comparable with catechin (188.0 ± 6.0 µg mL?1). Inhibition of lipid peroxidation of the extracts was also studied and their activity against peroxide radicals were lower than that of standard compounds (BHT, 79.0 ± 4.0 µg mL?1; quercetin, 166.0 ± 13.0 µg mL?1; Trolox, 175.0 ± 4.0 µg mL?1; PEE, 342.0 ± 17.0 µg mL?1; KEE, 202.0 ± 13.0 µg mL?1 and SCEE, 268.0 ± 13.0 µg mL?1. Copyright © 2007 Society of Chemical Industry  相似文献   

4.
BACKGROUND: The objective of the study was to determine the antioxidant activities of Korean black raspberry concentrate (KBR: Rubus coreanus Miq.) and Korean black raspberry wine concentrates (KBRW‐1 and KBRW‐2) using the DPPH (2,2‐diphenyl‐1‐picrylhydrazyl) radical scavenging assay. The apoptotic effects of the KBRW concentrates on various cancer cells were also investigated. RESULTS: Both the KBR concentrate and KBRW concentrates showed dose‐related antioxidant activities in the DPPH assay. At concentrations of 500 µg mL?1 and 1000 µg mL?1, the KBR concentrate antioxidant activities were 59% and 79%, respectively. KBRW‐1 and KBRW‐2 inhibited radical formation at 500 µg mL?1 by 19% and 48%, respectively. The antioxidant activity of KBRW‐2 was comparable to various red wines (RW‐1, RW‐2, RW‐3, and RW‐4). However, at 1000 µg mL?1, the antioxidant activities of KBRW‐1 and KBRW‐2 were 53% and 83% that of α‐tocopherol, respectively. Both RW‐1 and KBRW‐2 showed marked antiproliferative effects on all cancer cell types, with decreases in cell viability greater than 50%. This was co‐related with apoptotic characteristics, including chromatin condensation and apoptotic body formation, as determined by cell morphological assessment. Cell cycle analysis showed that treating AGS cells with RW‐1 and KBRW‐2 resulted in 25% and 30% apoptotic cell accumulation, respectively. KBRW‐2 induced the cleavage of poly(ADP‐ribose) polymerase (PARP) and the activation of caspase‐3 within the AGS cells. Levels of PARP cleavage were increased five‐ and three‐fold by RW‐1 and KBRW‐2, respectively, and the level of caspase‐3 was significantly increased by the treatment with KBRW‐2. CONCLUSION: Overall, the results of this study suggest that Korean black raspberry wine displays antioxidant activity comparable to that of imported red wines, and has anticancer effects that may be attributed to induction of the apoptotic pathway. Copyright © 2009 Society of Chemical Industry  相似文献   

5.
The commercial polysaccharides of alginic acid (medium (3500 cps, 2% solution) and low (250 cps, 2% solution) viscosities) were esterified with acidic methanol (1 mmol L?1 HCl) at 4 °C with gentle stirring for 5 days to obtain methyl esters of medium‐viscosity alginic acid (ME‐MVA) and low‐viscosity alginic acid (ME‐LVA). These ME‐MVA and ME‐LVA were reacted with alkaline hydroxylamine to obtain medium‐viscosity alginic acid hydroxamates (MVA‐NHOH) and LVA‐NHOH. The percentages of hydroxamic acid content in MVA‐NHOH and LVA‐NHOH were calculated as 25% and 20%, respectively. The hydroxamate derivatives of alginic acid were used to test the antioxidant and semicarbazide‐sensitive amine oxidase (SSAO) inhibitory activities in comparison with original materials (MVA and LVA). The half‐inhibition concentrations, IC50, of scavenging activity against 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) were 24.5 and 29.8 µg mL?1 for MVA‐NHOH and LVA‐NHOH, respectively. However, few scavenging activities of the MVA and LVA were found at the same concentrations. The IC50 of the positive control of butylated hydroxytoluene was 5 µg mL?1. The scavenging activity of DPPH radical was pH‐dependent, and the optimal pH for both of MVA‐NHOH and LVA‐NHOH was the Tris‐HCl buffer (pH 7.9). Using electron spin resonance (ESR) to detect the activity of scavenging hydroxyl radicals, both alginic acid hydroxamates showed dose‐dependent scavenging activities, and the IC50 was 90 and 92 µg mL?1, respectively, for MVA‐NHOH and LVA‐NHOH. Both alginic acid hydroxamates also exhibited protection against hydroxyl radical‐mediated DNA damage. Both MVA‐NHOH and LVA‐NHOH showed dose‐dependent inhibitory activities against bovine SSAO (2.53 units); the IC50 was 0.16 and 0.09 µg mL?1, respectively, for MVA‐NHOH and LVA‐NHOH, compared with 3.81 µg mL?1 of semicarbazide (positive controls). Amine oxidase activity staining also revealed that both MVA‐NHOH and LVA‐NHOH exhibited SSAO inhibitory activities. Both MVA‐NHOH and LVA‐NHOH showed mixed non‐competitive inhibition against bovine SSAO. It was found that the Vmax value was reduced and the Km value was either increased (added MVA‐NHOH, 0.05 µg mL?1) or reduced (added LVA‐NHOH, 0.11 µg mL?1) in the presence of alginic acid hydroxamate. Copyright © 2006 Society of Chemical Industry  相似文献   

6.
BACKGROUND: In this study the chemical composition, antioxidant activities and cytotoxic effect of the essential oils of Myristica fragrans (nutmeg) and Morinda citrifolia (mengkudu) were determined. RESULTS: Thirty‐eight compounds in nutmeg oil and six compounds in mengkudu oil were identified by gas chromatography–mass spectrometry. The free radical scavenging activity of nutmeg oil was superior of that mengkudu oil. The MTT assay of nutmeg oil on human colorectal carcinoma (HCT‐116) and human breast carcinoma (MCF‐7) cell lines showed IC50 values of 78.61 and 66.45 µg mL?1, respectively. The mengkudu oil exhibited IC50 values of 91.46 and 78.15 µg mL?1 for HCT‐116 and MCF‐7, respectively. CONCLUSION: The results showed that nutmeg oil can be developed as potent anti‐cancer and antioxidant drugs. Copyright © 2011 Society of Chemical Industry  相似文献   

7.
BACKGROUND By‐products generated during the processing of plant food can be considered a promising source of dietary fibre as a functional compound. The dietary fibre composition, soluble sugars and antioxidant activity of the extractable polyphenols of pea and broad bean by‐products have been analysed in this study. RESULTS: Total dietary fibre using AOAC methods plus hydrolysis (broad bean pod: 337.3 g kg?1; pea pod: 472.6 g kg?1) is higher (P < 0.05) in both by‐products than with the Englyst method (broad bean pod: 309.7 g kg?1; pea pod: 434.6 g kg?1). The main monomers are uronic acids, glucose, arabinose and galactose in broad bean pods. However, pea pods are very rich in glucose and xylose. The soluble sugars analysed by high‐performance liquid chromatography in both by‐products have glucose as the most important component, followed by sucrose and fructose. The ferric reducing antioxidant power (broad bean pod: 406.4 µmol Trolox equivalents g?1; pea pod: 25.9 µmol Trolox equivalents g?1) and scavenging effect on 2,2‐diphenyl‐1‐picrylhydrazyl radical (EC50 of broad bean pod: 0.4 mg mL?1; EC50 of pea pod: 16.0 mg mL?1) were also measured. CONCLUSIONS: Broad bean and pea by‐products are very rich in dietary fibre, particularly insoluble dietary fibre and their extractable polyphenols demonstrate antioxidant activity. Therefore they might be regarded as functional ingredients. Copyright © 2011 Society of Chemical Industry  相似文献   

8.
BACKGROUND: Total phenolics content, antioxidant activity and cytotoxicity of the methanol extracts from leaf parts of 13 Korean traditional salad plants were investigated in order to determine their properties. RESULTS: The highest phenolics content (mg ferulic acid equivalents kg?1 dry weight (d.w.), omit one) was found in methanol extracts from Polygonum aviculare, at 293.7 ± 6.0, followed by Euonymus alatus, at 250.7 ± 3.3, Saxifraga stolonifera, at 125.0 ± 8.1 and Ligularia fischeri, at 122.5 ± 5.9. The methanol plant extracts dose‐dependently increased free radical scavenging activity. Methanol extracts of Polygonum aviculare, Euonymus alatus and Saxifraga stolonifera, at 31 mg kg?1, exhibited the highest 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging activity (%) by 90.8 ± 4.2, 85.7 ± 3.9 and 64.1 ± 3.2, respectively. According to 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay, the methanol extracts from Portulaca oleracea (IC50 < 25.0 µg mL?1) showed the highest cytotoxicity against Calu‐6, followed by Plantago asiatica (49.2 µg mL?1) and Osmunda japonica (89.6 µg mL?1). CONCLUSION: Total phenolics content of the tested plant extracts was correlated with the DPPH radical scavenging activity, suggesting the phenolics compounds are contributing to the antioxidant properties of Korean salad plants. The leaf parts of the 13 Korean traditional salad plants described here that are currently used as foods may also provide some benefit to human health, and research into their potential benefits as preventative and/or therapeutic agents is warranted. Copyright © 2008 Society of Chemical Industry  相似文献   

9.
BACKGROUND: Hydrolysates prepared from sea urchin (Strongylocentrotus nudus) gonad by enzymatic treatment showed strong 1,1‐diphenyl‐2‐picrylhydrazyl radical scavenging activity and reducing power. RESULTS: Hydrolysis of S. nudus gonad by the commercial protease papain was optimised for maximum degree of hydrolysis (DH) and trichloroacetic acid‐soluble peptide index (TCA‐SPI) using response surface methodology. Results showed that the optimal conditions were the following: temperature of 48.83 °C, pH of 6.92, enzyme‐to‐substrate ratio of 3143 U g?1, and substrate concentration of 83.5 g L?1. Under these conditions, a DH of 27.96 ± 0.54% and a TCA‐SPI of 57.32 ± 0.63% were obtained. The hydrolysate prepared in the optimal conditions was fractionated by an ultra‐filtration system and the resultant fraction below 10 kDa was found to effectively scavenge hydroxyl radical (EC50 = 13.29 ± 0.33 mg mL?1) and hydrogen peroxide (EC50 = 16.40 ± 0.37 mg mL?1), inhibit lipid peroxidation (EC50 = 11.05 ± 0.62 mg mL?1), chelate Fe2+ (EC50 = 7.26 ± 0.44 mg mL?1), and protect mice macrophages against death induced by tert‐butyl hydroperoxide. CONCLUSION: Hydrolysates prepared from S. nudus gonad have the potential to be applied as natural antioxidant agents. Copyright © 2012 Society of Chemical Industry  相似文献   

10.
BACKGROUND: To investigate the volatile compounds and the antibacterial and antioxidant effects of the essential oils of Pinus densiflora needles (EPDN) and Pinus thunbergii needles (EPTN), the volatile compounds of steam‐distilled essential oils were analysed by gas chromatography–mass spectrometry. Antibacterial activities were analysed by performing disc‐agar diffusion assay and determining the minimum inhibitory concentrations (MICs) of the essential oils. Antioxidant activities were analysed via radical‐ and nitrite‐scavenging activity assays. RESULTS: The yields of EPDN and EPTN were 0.304% (v/w) and 0.296% (v/w), respectively. In the antibacterial activity assay, the MICs of EPDN and EPTN for Klebsiella pneumoniae, Shigella flexneri and Proteus vulgaris were < 0.4 mg mL?1. In the antioxidant activity assay, the 50% inhibitory concentrations (IC50) of EPDN and EPTN were 120 and 30 µg mL?1, respectively. At 1680 µg mL?1, both EPDN and EPTN exhibited > 50% nitrite‐scavenging activity. CONCLUSION: EPDN can be used as a natural antimicrobial substance. Copyright © 2011 Society of Chemical Industry  相似文献   

11.
R‐phycoerythrin (R‐PE) was purified from the red algae Bangia fusco‐purpurea after 35–50% ammonium sulphate fractionation followed by ion‐exchange column chromatography on DEAE‐Sepharose, resulting in a purity (A565/A280) ratio of 5.1. The circular dichroism spectroscopy results suggested that the structure of R‐PE is predominately helical. The antioxidant activity of R‐PE was studied and revealed changes in conformation and antioxidant activity at different temperatures and pH values. After in vitro‐simulated gastrointestinal (GI) digestion of R‐PE, the scavenging activity of ABTS radical (EC50, 769.9 μg mL?1), DPPH radical (EC50, 421.9 μg mL?1), hydroxyl radical (EC50, 32.4 μg mL?1) and reducing power (A700 = 0.5, 625.8 μg mL?1) were measured. Gel filtration chromatography analysis showed that the molecular weight distribution of the final GI digest that still contained high antioxidant activity was <3 kDa. Our present results indicate that digestion‐resistant antioxidant peptides of R‐PE may be obtained by in vitro GI proteinases degradation.  相似文献   

12.
The antimicrobial activities of anethole, anisic acid, and eugenol characterized from aniseed were tested against 18 organisms including both bacteria and yeasts. As far as their minimum inhibitory concentration (MIC) values were compared, they are nearly comparable but act in different ways. For example, anethole was noted to be effective against Saccharomyces cerevisiae with a minimum fungicidal concentration (MFC) of 200 µg mL?1 but the activity was observed only when this yeast was growing on fermentable carbon sources in a hypoxic condition. On the other hand, eugenol was effective against S. cerevisiae with an MFC of 800 µg mL?1 in any growing conditions. Anisic acid showed fungistatic activity against this yeast with an MIC of 400 µg mL?1, but not fungicidal up to 1600 µg mL?1. Copyright © 2007 Society of Chemical Industry  相似文献   

13.
BACKGROUND: Cryptococcus laurentii is a well‐known postharvest yeast antagonist. N6‐benzyladenine (6‐BA), a cytokinin plant hormone, has a role in retarding ripening and senescence of harvested produce. This study was conducted to evaluate the efficacy of C. laurentii and 6‐BA in reducing the blue mould disease of apple fruit. RESULTS: The combination of C. laurentii with 6‐BA (20 µg mL?1) was more effective in suppressing the Penicillium expansum infection in apple fruit wounds than C. laurentii alone, although 6‐BA (20 µg mL?1) alone neither affected the growth of C. laurentii nor reduced the incidence of the blue mould disease in vivo. Moreover, treatment of apple fruit with C. laurentii and 6‐BA (20 µg mL?1) resulted in stimulation of superoxide dismutase activity but in inhibition of the increase in peroxidase activity. CONCLUSION: 6‐BA (20 µg mL?1) could enhance the efficacy of C. laurentii in reducing the postharvest blue mould disease of apple fruit, which offered great potential in minimizing the postharvest decay of apple fruit in an integrated pest management strategy. Copyright © 2008 Society of Chemical Industry  相似文献   

14.
To investigate two‐sided functions of tea polyphenols (TP) in antinutrition and energy balance modulation, TP were extracted from Chinese green tea and used to complex porcine pancreas α‐amylase (PPA). Changes of PPA in activity and secondary conformations were analysed. Porcine pancreas α‐amylase was found sensitive to TP treatment. Tea polyphenols exhibited IC50 at 0.41 mg mL?1 against PPA and maximum inhibitory rate (98.17%) at 3.0 mg mL?1. Tea polyphenols inhibition was concluded as noncompetitive pattern based on its unchanged Km value (0.98 mg mL?1) for soluble starch substrate. Tea polyphenols inhibition arose from pH 1.5 to 10.14, covering gastric and intestinal environments inside body. Circular dichroism spectra analysis revealed regular changes of PPA in secondary conformations (increased proportions of α‐helix and β‐sheet) prior to its inactivation at low TP concentrations. Tea polyphenols‐inhibited PPA had distinct double‐negative peaks at 204 nm and 208 nm. Porcine pancreas α‐amylase was inactivated by TP in ways of complexation and modification of secondary conformations.  相似文献   

15.
BACKGROUND: Chitosan can form antimicrobial, semi‐permeable barriers that limit gas exchange and reduces water loss in fruits. Consumer interest in fresh‐cut papaya fruit is leading to increasing demand because of its sensorial and antioxidant properties. However, papaya is a highly perishable product that is prone to loss of weight, loss of firmness and microbial attack. The aim of this study was to evaluate the effect of chitosan coatings on the overall quality of fresh‐cut papaya. Chitosan coatings of low (LMWC), medium (MMWC) and high (HMWC) molecular weights, at concentrations of 0.01 and 0.02 g mL?1, were applied to fresh‐cut papaya cubes. The treated cubes were stored at 5 °C and changes in quality were evaluated. RESULTS: MMWC maintained the highest color values (L* and b*) and firmness. Chitosan coatings suppressed mesophilic plate count, and the growth of molds and yeast, compared to controls. The MMWC coatings at 0.02 g mL?1 resulted in the highest antimicrobial activity and decreased the activity of the enzymes polygalacturonase and pectin methylesterase, followed by low and high MW chitosan coatings at 0.02 g mL?1. CONCLUSION: The application of the MMWC treatment at 0.02 g mL?1 could be used to reduce deteriorative processes, maintain quality and increase the shelf life of fresh‐cut papaya stored at 5 °C. Copyright © 2008 Society of Chemical Industry  相似文献   

16.
BACKGROUND: The potential use of hard‐to‐cook (hardened) chickpeas to obtain value‐added functional food ingredients was evaluated. For that purpose, some nutraceutical and functional attributes of several chickpea protein hydrolysates (CPHs) prepared from both fresh and hard‐to‐cook grains were evaluated. RESULTS: All the CPHs prepared from both fresh and hard‐to‐cook grains, with the enzymes alcalase, pancreatin and papain, showed high angiotensin converting enzyme inhibitory (ACE‐I) activity with IC50 values ranging from 0.101 to 37.33 µg mL?1; similarly, high levels of antioxidant activity (around 18.17–95.61 µmol Trolox equivalent antioxidant capacity µg?1 CPH) were obtained through both the 2,2‐diphenyl‐1‐picrylhydrazyl and 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) methods. Regarding functional characterization of the CPHs, oil absorption values ranged from 1.91 to 2.20 mL oil g?1 CPH, with water solubility almost 100% from pH 7 to 10. CONCLUSION: The high antioxidant and ACE‐I activities as well as the good functional properties of the CPH prepared from both fresh and hard‐to‐cook grains, suggest its use in food formulations with value added in human health. Copyright © 2012 Society of Chemical Industry  相似文献   

17.
BACKGROUND: Folic acid (FA) is essential for healthy people (reference daily intake 400 µg day?1) and pregnant women (600 µg day?1). Insufficient intake of FA will increase the risk of neural tube defects in newborns. In this study an indirect enzyme‐linked immunosorbent assay was developed for rapid and convenient detection of FA in vitamin‐fortified foods. RESULTS: A carbodiimide‐modified active ester method was used to synthesise the immunogen (FA–bovine serum albumin (BSA) conjugate) to raise polyclonal antibodies for FA. The coupling ratio of FA with BSA was determined to be 14:1 (molar ratio). The detection limit of the immunoassay was 3.0 ng mL?1 in buffer, 3.52 ng mL?1 in energy drink, 11.91 ng mL?1 in milk and 16.50 ng mL?1 in milk powder. Intra‐ and inter‐assay variability ranged from 6.6 to 15.1%. Analytical recoveries of FA‐spiked samples were 88.3–108.9%. CONCLUSION: The immunoassay developed in this study can be used as a simple, rapid and accurate method for fast semi‐quantitative and quantitative on‐site analysis of FA in food products. Copyright © 2012 Society of Chemical Industry  相似文献   

18.
A novel antifungal peptide from foxtail millet seeds   总被引:1,自引:0,他引:1  
BACKGROUND: Antifungal proteins (AFP) help plants to combat phytopathogenic fungi and thus protect plants from the devastating damage caused by fungal infections and prevent massive economic losses. To date, several proteins with antibacterial and/or antifungal properties have been isolated and characterized from different plant species and tissues; however, there are no reports concerning the antifungal peptide from foxtail millet seeds. RESULTS: An antifungal peptide with a molecular mass of 26.9 kDa was isolated from dry seeds of the foxtail millet (Setaria italica (L.) Beauv.), using a procedure that involved four chromatographic steps. The antifungal peptide was adsorbed on CM‐Sepharose, Affi‐gel blue gel and Superdex 75. It was further purified by C18 reverse‐phase high‐performance liquid chromatography and submitted for analysis of peptide mass fingerprint. The Mascot peptide mass fingerprint of the isolated protein hit no existing protein (score > 60), and it was proved to be a novel antifungal peptide. It inhibited mycelial growth in Alternaria alternate with an IC50 of 1.3 µmol L?1, and it also exhibited antifungal activity against Trichoderma viride, Botrytis cinerea and Fusarium oxysporum. Transmission electron microscopy of mold forms of Alternaria alternate after incubation with 20 µg mL?1 of the antifungal protein for 48 h revealed marked ultrastructural changes in the fungus. CONCLUSION: A novel antifungal peptide with high potency was isolated from foxtail millet seeds. Copyright © 2011 Society of Chemical Industry  相似文献   

19.
BACKGROUND: The aims of this study were to examine the chemical composition of the essential oil isolated from the floral parts of Nandina domestica Thunb. by hydrodistillation, and to test the efficacy of essential oil and various leaf extracts (n‐hexane, chloroform, ethyl acetate and methanol) as an antifungal potential against a panel of agricultural plant pathogens. RESULTS: The GC‐MS analysis determined that 79 compounds, which represented 87.06% of total oil, were present in the oil containing mainly 1‐indolizino carbazole (19.65%), 2‐pentanone (16.4%), mono phenol (12.1%), aziridine (9.01%), methylcarbinol (4.6%), ethanone (3.3%), furfural (2.96%), 3,5‐dimethylpyrazole (1.29%) and 2(5H)‐furanone (1.32%). The oil (1000 ppm disc?1) and the leaf extracts (1500 ppm disc?1) revealed remarkable antifungal effect against Fusarium oxysporum, Fusarium solani, Phytophthora capsici, Colletotrichum capsici, Sclerotinia sclerotiorum, Botrytis cinerea and Rhizoctonia solani in the growth inhibition range of 53.3–64.3% and 33.3–56.0%, respectively, along with their respective values for mimimum inhibitory concentration (MIC) ranging from 125 to 1000 µg mL?1 and 500 to 2000 µg mL?1. The values for minimal fungicidal concentration (MFC) of the oil and extracts were obtained in the range of 125 to 1000 µg mL?1 and 500 to 2000 µg mL?1, respectively. The essential oil also had a strong detrimental effect on spore germination of all the plant pathogens tested along with concentration as well as time‐dependent kinetic inhibition of B. cinerea. CONCLUSION: The results obtained in this study demonstrate that N. domestica mediated oil and extracts could become potential alternatives to synthetic fungicides for controlling certain important agricultural plant pathogenic fungi. Copyright © 2008 Society of Chemical Industry  相似文献   

20.
A new immunomodulatory protein (PCiP) was purified from an edible golden oyster mushroom (Pleurotus citrinopileatus) by extraction with 5% (v/v) cold acetic acid in the presence of 0.1% (v/v) 2‐mercaptoethanol, followed by ammonium sulfate fractionation, DE‐52 and MonoQ anion‐exchange chromatography. Electrophoresis assays demonstrated that the molecular mass of PCiP was approximately 15.0 kDa and its pI was around 5.2. PCiP is a simple protein without carbohydrate, and cannot agglutinate mouse red blood cells, suggesting PCiP is not a lectin. In addition, PCiP (5–20 µg mL?1) alone activated murine splenocytes, and markedly increased their proliferation and gamma‐interferon (IFN‐γ secretion, but suppressed MTT metabolization, while murine splenocytes were simultaneously stimulated by the mitogen concanavalin A (ConA). Furthermore, PCiP (5–20 µg mL?1) directly activated murine macrophages and increased the production of both the nitric oxide (NO) and tumor necrosis factor‐alpha (TNF‐α by RAW 264.7 macrophages. These findings suggest that PCiP could strengthen both the innate and adaptive responses of its host. Copyright © 2007 Society of Chemical Industry  相似文献   

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