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1.
The inflorescence of cultivated Coptis chinensis has been valued for tea production for many years in China. The antioxidant activities of C. chinensis inflorescence extracts prepared by various solvents were investigated by using several established in vitro systems: 2,2′-azinobis(3-ethylbenzthiazoline-6-sulphonic acid (ABTS), α,α-diphenyl-β-picrylhydrazyl (DPPH) and superoxide radical scavenging assays, reducing power assay, and ferrothiocyanate (FTC) and thiobarbituric acid (TBA) assays. The results showed that the 70% ethanol extract (EE) had the strongest antioxidant activity in vitro among the various extracts. Based on the in vitro results, EE was used to evaluate the antioxidant activity of C. chinensis inflorescence in vivo. The liver and kidney of intoxicated animals showed a significant decrease in superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) levels, while the malondialdehyde (MDA) level showed a significant increase. These changes were significantly reversed after treatment with EE and the standard vitamin E. Thus, the C. chinensis inflorescence may be a valuable natural source that can be applicable to food industries.  相似文献   

2.
Coriander is commonly used for medicinal purposes, food applications, cosmetics and perfumes. Herein, the production of antioxidants in vegetative parts (leaves and stems) of in vivo and in vitro grown samples was compared. In vitro samples were clone A- with notorious purple pigmentation in stems and leaves and clone B- green. Seeds were also studied as they are used to obtain in vivo and in vitro vegetative parts. Lipophilic (tocopherols, carotenoids and chlorophylls) and hydrophilic (sugars, ascorbic acid, phenolics, flavonols and anthocyanins) compounds were quantified. The antioxidant activity was evaluated by radical scavenging activity, reducing power and lipid peroxidation inhibition. The in vivo sample showed the highest antioxidant activity mainly due to its highest levels of hydrophilic compounds. Otherwise, in vitro samples, mainly clone A, gave the highest concentration in lipophilic compounds but a different profile when compared to the in vivo sample. Clones A and B revealed a lack of β-carotene, β- and δ-tocopherols, a decrease in α-tocopherol, and an increase in γ-tocopherol and clorophylls in comparison to the in vivo sample. In vitro culture might be useful to explore the plants potentialities for industrial applications, controlling environmental conditions to produce higher amounts of some bioactive products.  相似文献   

3.
The precise level of environmental control in vitro may aid in identifying genetically superior plant germplasm for rooting characteristics (RC) linked to increased foraging for plant nitrogen (N). The objectives of this research were to determine the phenotypic variation in root morphological responses of 49 Solanum chacoense (chc), 30 Solanum tuberosum Group Phureja – Solanum tuberosum Group Stenotomum (phu-stn), and three Solanum tuberosum (tbr) genotypes to 1.0 and 0.5 N rate in vitro for 28 d, and identify genotypes with superior RC. The 0.5 N significantly increased density of root length, surface area, and tips. All RC were significantly greater in chc than in either phu-stn or tbr. Based upon clustering on root length, surface area, and volume, the cluster with the greatest rooting values consisted of eight chc genotypes that may be utilized to initiate a breeding program to improve RC in potato.  相似文献   

4.
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   

5.
6.
Antioxidant activity of fresh Allium sativum L. (garlic) is well known and is mainly due to unstable and irritating organosulphur compounds. Fresh garlic extracted over a prolonged period (up to 20 months) produces odourless aged garlic extract (AGE) containing stable and water soluble organosulphur compounds that prevent oxidative damage by scavenging free radicals. The aim of this study was to investigate the in vitro antioxidant activity of aged (up to 20 months) 15% hydroethanolic extracts of different parts (bulbs, bulblets, flower bulblets, flowers, and leaves) of three Allium spontaneous species which are endemic for Italian flora: Allium neapolitanum Cyr., Allium subhirsutum L., Allium roseum L. and to compare it with the in vitro antioxidant activity of aged 15% hydroethanolic extracts of bulbs and leaves of garlic. The antioxidant potential of aged extracts of all species has been evaluated using two different spectrophotometric assays: 2,2-diphenylpicrylhydrazyl (DPPH) test and the ferric reducing/antioxidant power (FRAP) assay. Furthermore the polyphenol content was determined. The aged extracts obtained from the leaves showed the best antioxidant activity, followed by flowers and then by bulbs in both used tests, while flower bulblets and bulblets exhibited lower results or no activity. The polyphenol content was generally directly correlated with antioxidant/antiradical activity. This study confirms the data obtained in previous researches, the wild-type species of Allium and in particular organs other than bulbs are more active and efficacious than garlic bulb. Surely leaves of these Allium spp. deserve special attention.  相似文献   

7.
Olive leaves represent a quantitatively significant by-product of agroindustry. They are rich in phenols, mainly oleuropein, which can be hydrolyzed into several bioactive compounds, including hydroxytyrosol. In this study, water extract from olive leaves ‘Biancolilla’ was analyzed for polyphenol profile, DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity and protective effect on differentiated Caco-2 cells. The efficacy of two enzymatic treatments in promoting the release of bioactive phenols was investigated: a) enzymatic extract from Wickerhamomyces anomalus, characterized by β-glucosidase and esterase activities; b) commercial β-glucosidase. Composition and bioactivity of the resulting extracts were compared. The results showed that the yeast-treated extract presented hydroxytyrosol content and DPPH radical scavenging activity comparable to those obtained using commercial β-glucosidase; however, it was showed the additional presence of hydroxycinnamic acids. In experiments on Caco-2 cells, the leaf extracts promoted the recovery of cell membrane barrier at different minimum effective concentrations. The high specificity of W. anomalus enzymatic extract may represent an effective tool for the release of bioactive phenols from olive by-products.  相似文献   

8.

Background

The rice blast resistance gene Pi54 was cloned from Oryza sativa ssp. indica cv. Tetep, which conferred broad-spectrum resistance against Magnaporthe oryzae. Pi54 allelic variants have been identified in not only domesticates but also wild rice species, but the majority of japonica and some indica cultivars lost the function.

Results

We here found that Pi54 (Os11g0639100) and its homolog Os11g0640600 (named as #11) were closely located on a 25 kbp region in japonica cv. Sasanishiki compared to a 99 kbp region in japonica cv. Nipponbare. Sasanishiki lost at least six genes containing one other R-gene cluster (Os11g0639600, Os11g0640000, and Os11g0640300). Eight AA-genome species including five wild rice species were classified into either Nipponbare or Sasanishiki type. The BB-genome wild rice species O. punctata was Sasanishiki type. The FF-genome wild rice species O. brachyantha (the basal lineage of Oryza) was neither, because Pi54 was absent and the orientation of the R-gene cluster was reversed in comparison with Nipponbare-type species. The phylogenetic analysis showed that #11gene of O. brachyantha was on the root of both Pi54 and #11 alleles. All Nipponbare-type Pi54 alleles were specifically disrupted by 143 and 37/44?bp insertions compared to Tetep and Sasanishiki type. In addition, Pi54 of japonica cv. Sasanishiki lost nucleotide-binding site and leucine-rich repeat (NBS–LRR) domains owing to additional mutations.

Conclusions

These results suggest that Pi54 might be derived from a tandem duplication of the ancestor #11 gene in progenitor FF-genome species. Two divergent structures of Pi54 locus caused by a mobile unit containing the nearby R-gene cluster could be developed before domestication. This study provides a potential genetic resource of rice breeding for blast resistance in modern cultivars sustainability.
  相似文献   

9.
An efficient protocol for hairy root induction in Solanum tuberosum was established using Agrobacterium rhizogenes. Transformation of Desiree was more efficient than with Shepody or Purple Majesty. Transformation efficiency of Desiree tuber discs (97% transformation efficiency) was higher in comparison to root (67% transformation efficiency), stem (61% transformation efficiency) and leaf (14% transformation efficiency) explants. Bacterial density, culture parameters, explant type, and genotype influenced the transformation efficiency, as well as the growth of hairy roots. Hairy root transformation efficiency in explants treated with acetosyringone was enhanced from 72 to 89% in Purple Majesty tubers and 56 to 80% in roots during co-cultivation. The growth rate of hairy roots from tuber discs was about 5 times greater than that of hairy roots from leaves. Tuber hairy roots were highly resistant to kanamycin in the absence of NPT II. This study describes the efficient generation of hairy roots in different potato tissues and cultivars that can provide a fast method to generate transformed tissue or be used for production of secondary metabolites.  相似文献   

10.
A novel method was developed to prepare the antibacterial cotton fabrics through in situ deposition of silver nanoparticles on the cotton fabrics by the reduction of Ag+ without any reductant and dispersant. The data showed that by immersing the cotton fabrics in 160 mM AgNO3 solution at 90 °C, the amount of silver nanoparticles was increased from 0.6890 to 1.3561 mg per gram of fabrics with the increase of reaction time from 10 to 50 min. The obtained cotton fabrics showed excellent antibacterial activity and laundering durability, in which the bacterial reduction was still 98.5 and 94.3 % to Escherichia coli and Staphylococcus aureus, respectively, even after the fabrics were washed for 20 cycles. Thus, this facile in stitu reduction method without any other reducers or stabilizers may bring a promising and green strategy to produce functional cotton fabrics.  相似文献   

11.
Avocado seed contains elevated levels of phenolic compounds and exhibits antioxidant properties. We investigated the effect of Avocado Seed Flour (ASF) on the lipid levels in mice on a hyperlipidemic diet. The concentration of phenols was determined by high-performance liquid chromatography, antioxidant activity was evaluated using the Trolox equivalent antioxidant capacity method, and dietary fiber was measured using the Association of Official Analytical Chemists (AOAC) method. The LD50 of ASF was determined using Lorke’s method and hypolipidemic activity was evaluated in a hypercholesterolemic model in mice. Protocatechuic acid was the main phenolic compound found in ASF, followed by kaempferide and vanillic acid. The total phenolic content in the methanolic extract of ASF was 292.00 ± 9.81 mg gallic acid equivalents/g seed dry weight and the antioxidant activity resulted in 173.3 μmol Trolox equivalents/g DW. In addition, a high content of dietary fiber was found (34.8%). The oral LD50 for ASF was 1767 mg/kg body weight, and treatment with ASF significantly reduced the levels of total cholesterol, LDL-C, and prediction of the atherogenic index. Therefore, the antioxidant activity of phenolic compounds and dietary fiber in ASF may be responsible for the hypocholesterolemic activity of ASF in a hyperlipidemic model of mice.  相似文献   

12.

Background

Fungal endophytes are the living symbionts which cause no apparent damage to the host tissue. The distribution pattern of these endophytes within a host plant is mediated by environmental factors. This study was carried out to explore the fungal endophyte community and their distribution pattern in Asparagus racemosus and Hemidesmus indicus growing in the study area.

Results

Foliar endophytes were isolated for 2 years from A. racemosus and H. indicus at four different seasons (June–August, September–November, December–February, March–May). A total of 5400 (675/season/year) leaf segments harbored 38 fungal species belonging to 17 genera, 12 miscellaneous mycelia sterile from 968 isolates and 13 had yeast like growth. In A. racemosus, Acremonium strictum and Phomopsis sp.1, were dominant with overall relative colonization densities (RCD) of 7.11% and 5.44% respectively, followed by Colletotrichum sp.3 and Colletotrichum sp.1 of 4.89% and 4.83% respectively. In H. indicus the dominant species was A. strictum having higher overall RCD of 5.06%, followed by Fusarium moniliforme and Colletotrichum sp.2 with RCD of 3.83% and 3%, respectively. Further the overall colonization and isolation rates were higher during the wet periods (September–November) in both A. racemosus (92.22% and 95.11%) and H. indicus (82% and 77.11%).

Conclusion

Study samples treated with 0.2% HgCl2 and 75% EtOH for 30 s and 1 min, respectively, confirmed most favorable method of isolation of the endophytes. Owing to high mean isolation and colonization rates, September–November season proved to be the optimal season for endophyte isolation in both the study plants. Assessing the bioactive potential of these endophytes, may lead to the isolation of novel natural products and metabolites.
  相似文献   

13.
The present study aimed to evaluate for the first time the phenols, flavonoids, carotenoids, capsaicin and dihydrocapsaicin content and the antioxidant and hypoglycemic properties of Capsicum annuum var. acuminatum small and C. annuum var. cerasiferum air-dried fruits. The ethanol extract of C. annuum var. acuminatum small, characterized by the major content of total poliphenols, flavonoids, carotenoids and capsaicinoids, showed the highest radical scavenging activity (IC50 of 152.9 μg/ml). On the contrary, C. annuum var. cerasiferum showed a significant antioxidant activity evaluated by the β-carotene bleaching test (IC50 of 3.1 μg/ml). The lipophilic fraction of both C. annuum var. acuminatum and C. annuum var. cerasiferum exhibited an interesting and selective inhibitory activity against α-amylase (IC50 of 6.9 and 20.1 μg/ml, respectively).  相似文献   

14.
Symplocos spicata (local name: Dom sheng) belonging to Family Symplococeae produces yellowish brown natural dye which has been used for dyeing textiles since ancient times by the Monpas tribe of Arunachal Pradesh. Symplocos spicata (Dom Sheng) was found in the Lumla area of Tawang district. Leaves of the plant are used by the Monpas and Tibetans for extraction of dye. Innovative sonicator dyeing with S. spicata showed that pretreatment with 2–4% metal mordant of the weight of the fabric is optimum showing very good fastness properties for dyed natural polymers such as cotton, wool, and silk. CIELab and K/S of the dyed fabrics were also evaluated. The superiority of sonicator dyeing over conventional dyeing has been established through this study.  相似文献   

15.

Background  

Plant defense strategy is usually a result of trade-offs between growth and differentiation (i.e. Optimal Defense Theory – ODT, Growth Differentiation Balance hypothesis – GDB, Plant Apparency Theory – PAT). Interaction between the introduced green alga Caulerpa taxifolia and the endemic seagrass Posidonia oceanica in the Mediterranean Sea offers the opportunity to investigate the plausibility of these theories. We have accordingly investigated defense metabolite content and growth year-round, on the basis of an interaction gradient.  相似文献   

16.
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   

17.

Background

Rice plays an extremely important role in food safety because it feeds more than half of the world’s population. Rice grain yield depends on biomass and the harvest index. An important strategy to break through the rice grain yield ceiling is to increase the biological yield. Therefore, genes associated with organ size are important targets for rice breeding.

Results

We characterized a rice mutant gns4 (grain number and size on chromosome 4) with reduced organ size, fewer grains per panicle, and smaller grains compared with those of WT. Map-based cloning indicated that the GNS4 gene, encoding a cytochrome P450 protein, is a novel allele of DWARF11 (D11). A single nucleotide polymorphism (deletion) in the promoter region of GNS4 reduced its expression level in the mutant, leading to reduced grain number and smaller grains. Morphological and cellular analyses suggested that GNS4 positively regulates grain size by promoting cell elongation. Overexpression of GNS4 significantly increased organ size, 1000-grain weight, and panicle size, and subsequently enhanced grain yields in both the Nipponbare and Wuyunjing7 (a high-yielding cultivar) backgrounds. These results suggest that GNS4 is key target gene with possible applications in rice yield breeding.

Conclusion

GNS4 was identified as a positive regulator of grain number and grain size in rice. Increasing the expression level of this gene in a high-yielding rice variety enhanced grain yield. GNS4 can be targeted in breeding programs to increase yields.
  相似文献   

18.
Teff (Eragrostis tef) is a fine stemmed annual grass and gluten free small grain that is of interest as a forage, cover, or a rotation crop. Little is known about the susceptibility of teff to many diseases. Teff could be grown in rotation with potato in the northwestern United States provided teff cultivation is economical and does not increase soil populations for pathogens affecting rotation crops such as Verticillium dahliae. Verticillium dahliae infects a wide range of dicotyledonous plants, making it one of the most important fungal pathogens of crop plants in North America, including potato. The objective of this study was to quantify the susceptibility of teff to eight V. dahliae isolates and compare the susceptibility of teff to eggplant. Teff was confirmed as a host for V. dahliae, as indicated by the presence of microsclerotia in teff stems and roots after artificial inoculation in two years of greenhouse studies. The number of microsclerotia produced in teff did not differ between mint and potato pathotypes of V. dahliae. No V. dahliae isolate produced significantly greater numbers of microsclerotia than any of the seven other isolates tested in a two-year study. Microsclerotia production of V. dahliae in teff was consistently less than in susceptible eggplant cv. Night shadow in both greenhouse experiments (P?<?0.02). It is unlikely that teff infected by V. dahliae will proliferate microsclerotia of mint or potato-aggressive pathotypes, especially when compared to susceptible eggplant cultivars.  相似文献   

19.
Verticillium wilt is a fungal disease of potato caused by two species of Verticillium, V. dahliae and V. albo atrum. The pathogen infects the vascular tissue of potato plants through roots, interfering with the transport of water and nutrition, and reducing both the yield and quality of tubers. We have evaluated the reaction of 283 potato clones (274 cultivars and nine breeding selections) to inoculation with V. dahliae under greenhouse conditions. A significant linear correlation (r = 0.4, p < 0.0001) was detected between plant maturity and partial resistance to the pathogen, with late maturing clones being generally more resistant. Maturity-adjusted resistance, that takes into consideration both plant maturity and resistance, was calculated from residuals of the linear regression between the two traits. Even after adjusting for maturity, the difference in the resistance of clones was still highly significant, indicating that a substantial part of resistance cannot be explained by the effect of maturity. The highest maturity-adjusted resistance was found in the cv. Navajo, while the most susceptible clone was the cv. Pungo. We hope that the present abundance of data about the resistance and maturity of 283 clones will help potato breeders to develop cultivars with improved resistance to V. dahliae.  相似文献   

20.
The aim of this study was to investigate the bioactivity of the essential oil isolated from Origanum vulgare L. (EOv). We analyzed the in vivo anti-inflammatory properties in a mouse-airway inflammation model and the in vitro antimicrobial activity, genotoxicity over the anaphase-telophase with the Allium cepa strain and its cytotoxicity/viability in A549 culture cells. In vivo, EOv modified the levels of tumor necrosis factor -α and viable activated macrophages and was capable to mitigate the effects of degradation of conjugated dienes. In vitro, EOv reduced the viability of cultured A549 cells as well as the mitotic index and a number of chromosomal aberrations; however, it did not change the number of phases. We found that EOv presents antimicrobial activity against different Gram (?) and (+) strains, measured by disc-diffusion test and confirmed with a more accurate method, the AutoCad software. We postulate that EOv presents antibacterial, antioxidant and chemopreventive properties and could be play an important role as bioprotector agent.  相似文献   

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