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1.
Single nucleotide polymorphisms (SNPs) are widely employed in the studies of population genetics, molecular breeding and conservation genetics. In this study, we explored a simple route to develop SNPs from non-model species based on screening the library of single copy nuclear genes (SCNGs). Through application of this strategy in Panax, we identified 160 and 171 SNPs from P. quinquefolium and P. ginseng, respectively. Our results demonstrated that both P. ginseng and P. quinquefolium possessed a high level of nucleotide diversity. The number of haplotype per locus ranged from 1 to 12 for P. ginseng and from 1 to 9 for P. quinquefolium, respectively. The nucleotide diversity of total sites (πT) varied between 0.000 and 0.023 for P. ginseng and 0.000 and 0.035 for P. quinquefolium, respectively. These findings suggested that this approach is well suited for SNP discovery in non-model organisms and is easily employed in standard genetics laboratory studies.  相似文献   

2.
This study aimed to investigate the contents and the antioxidant activities of various fractions from ethanol extract of the root powder of Panax ginseng C. A. Meyer using supercritical carbon dioxide (SC-CO2) fractionation technology. Results showed that the DPPH (1,1-diphenyl-2-picrylhydrazyl) radicals scavenging activity was higher in the residue and Fraction 1 compared with that in the extract. Increasing amounts of total phenolic compounds, total polysaccharides, and saponins were strongly correlated with a higher antioxidant capacity. SC-CO2 extractive fractionation technology could effectively fractionate the bioactive ingredients from Panax ginseng C. A. Meyer and increase the antioxidant activities of its fractions.  相似文献   

3.
Panax ginseng is a valuable traditional Chinese medicine in Northeast China. Ginsenoside, the active component of ginseng, has not been investigated much for its effects on aging and its underlying mechanism(s) of action. Here, we investigated the effects of total ginsenoside (TG), a mixture of the primary active ginsenosides from Panax ginseng, on the lifespan of Caenorhabditis elegans (C. elegans). We found that TG extended the lifespan of C. elegans and reduced lipofuscin accumulation. Moreover, TG increased the survival of C. elegans in response to heat and oxidative stress via the reduction of ROS. Next, we used RNA-seq to fully define the antiaging mechanism(s) of TG. The KEGG pathway analysis showed that TG can prolong the lifespan and is involved in the longevity regulating pathway. qPCR showed that TG upregulated the expression of nrh-80, daf-12, daf-16, hsf-1 and their downstream genes. TG also reduced the fat accumulation and promoted lipid metabolism. Moreover, TG failed to extend the lifespan of daf-16 and hsf-1 mutants, highlighting their role in the antiaging effects of TG in C. elegans. The four main constitution of TG were then confirmed by HPLC and included ginsenoside Re, Rg1, Rg2 and Rd. Of the ginsenosides, only ginsenoside Rd prolonged the lifespan of C. elegans to levels comparable to TG. These findings provided mechanistic insight into the antiaging effects of ginsenoside in C. elegans.  相似文献   

4.
Antioxidant activities of selected oriental herb extracts   总被引:9,自引:0,他引:9  
Antioxidant activities of methanol extracts of 180 Oriental herbs were studied by determining the peroxide values of linoleic acid during storage at 50°C. Among the herb extracts tested, 44 species showed strong antioxidant activities on the oxidation of linoleic acid. The antioxidative effects of these 44 selected herb extracts were studied further in a methyl linoleate system during storage for 35 d. Among the 44 species tested, 11 species had particularly high antioxidative effects. The effects of type of extraction solvent (methanol, petroleum ether and ethyl acetate) on the antioxidant activities of the 11 species were studied. Antioxidant activities of most herb extracts were greatly dependent on the extraction solvent used; however, some of the extracts showed strong antioxidant activities regardless of the solvents used for the extraction. Among the 11 herbs selected, based on the antioxidant activity of their methanol extracts, two (i.e.,Psoralea corylifolia L. andSorphora angustifolia Sieb. & Zucc.) were selected for further study in lard held at 75°C for 7 d. The methanol extracts ofP. corylifolia L. andS. angustifolia Sieb. & Zucc. greatly decreased the peroxide formation of lard during storage. Treatment with 0.20% methanolic extract ofP. corylifolia L. exhibited significantly stronger antioxidant effect on the oxidation of lard than treatment with 0.02% butylated hydroxyanisole (P<0.05).  相似文献   

5.
为开发人参发酵液在化妆品领域的应用,使用食用级黄酒酵母发酵人参并测定发酵液中多糖、蛋白质和人参皂苷的含量。通过DPPH自由基清除实验和羟自由基清除实验测定其抗氧化能力,并将其作用于成纤维细胞,采用MTT细胞毒性试验评估其对成纤维细胞的增殖作用。用荧光定量PCR检测12种炎症相关的基因在人参发酵液作用的永生化表皮细胞中的表达量,评估人参发酵液的抗炎症效果。结果表明,人参发酵液富含多糖,质量浓度为6.982 g/L,蛋白质和人参皂苷的质量浓度分别为1.039和0.045 g/L。体积分数为10.49%的人参发酵液可清除50%的DPPH自由基,19.62%的人参发酵液可清除50%的羟自由基;体积分数为0.01%的人参发酵液培养的成纤维细胞存活率甚至超过100%,可有效促进细胞增殖;人参发酵液能引发炎症反应,并在短时间内激活并募集白细胞到炎症部位发挥免疫功能。  相似文献   

6.
Rb1-hydrolyzing β-glucosidase from Aspergillus niger KCCM 11239 was studied to develop a bioconversion process for minor ginsenosides. The specific activity of the purified enzyme was 46.5 times greater than that of the crude enzyme. The molecular weight of the native enzyme was estimated to be approximately 123 kDa. The optimal pH of the purified enzyme was pH 4.0, and the enzyme proved highly stable over a pH range of 5.0–10.0. The optimal temperature was 70 °C, and the enzyme became unstable at temperatures above 60 °C. The enzyme was inhibited by Cu2+, Mg2+, Co2+, and acetic acid (10 mM). In the specificity tests, the enzyme was found to be active against ginsenoside Rb1, but showed very low levels of activity against Rb2, Rc, Rd, Re, and Rg1. The enzyme hydrolyzed the 20-C,β-(1→6)-glucoside of ginsenoside Rb1 to generate ginsenoside Rd and Rg3, and hydrolyzed 3-C,β-(1→2)-glucoside to generate F2. The properties of the enzyme indicate that it could be a useful tool in biotransformation applications in the ginseng industry, as well as in the development of novel drug compounds.  相似文献   

7.
Oxidative stress caused by reactive oxygen species (ROS, O2, HO•, and H2O2) affects the aging process and the development of several diseases. A new frontier on its prevention includes functional foods with both specific probiotics and natural extracts as antioxidants. In this work, Panax ginseng C.A. Meyer berries extract was characterized for the presence of beneficial molecules (54.3% pectin-based polysaccharides and 12% ginsenosides), able to specifically support probiotics growth (OD600nm > 5) with a prebiotic index of 0.49. The administration of the extract to a probiotic consortium induced the production of short-chain fatty acids (lactic, butyric, and propionic acids) and other secondary metabolites derived from the biotransformation of Ginseng components. Healthy and tumoral colorectal cell lines (CCD841 and HT-29) were then challenged with these metabolites at concentrations of 0.1, 0.5, and 1 mg/mL. The cell viability of HT-29 decreased in a dose-dependent manner after the exposition to the metabolites, while CCD841 vitality was not affected. Regarding ROS production, the metabolites protected CCD841 cells, while ROS levels were increased in HT-29 cells, potentially correlating with the less functionality of glutathione S-transferase, catalase, and total superoxide dismutase enzymes, and a significant increase in oxidized glutathione.  相似文献   

8.
嘧菌环胺在人参根茎叶及土壤中的残留动态   总被引:1,自引:0,他引:1  
[目的]我国对人参中嘧菌环胺残留动态尚未研究,旨在为其在人参上使用合理化.[方法]通过田间试验和气质联用技术研究了50%嘧菌环胺WG在人参和土壤中的消解动态及最终残留量.[结果]施药剂量为推荐剂量的2倍(1 133.3 g a.i./hm2)时,半衰期为根11.8 d、茎15.7 d、叶16.5 d、土19.1 d,根、茎和土壤中残留量均远低于韩国MRL值(0.5 mg/kg).[结论]按照1 133.3 g a.i./hm2剂量处理,施药1次,建议我国在人参根茎和土壤中嘧菌环胺的MRL值暂定为0.5 mg/kg,安全间隔期根14 d,茎、土壤28 d,而参叶上残留量较高,建议MRL值暂定为1.0 mg/kg,安全间隔期无法确定.  相似文献   

9.
The lipid content and fatty acid (FA) composition of seeds from the Asian ginseng Panax ginseng growing naturally in taiga forests of the Russian Far East and seeds from cultivated ginseng were studied in this work. The total lipid content of seeds from both wild and cultivated plants was 9–12 % of fresh weight. FA were analyzed as isopropyl esters on a polar capillary column BD‐225, which allows good separation of petroselinic and oleic acids. The structure of FAs was confirmed using GC–MS of fatty acid methyl ester (FAME) and 4,4‐dimethyloxazoline derivatives. In all the seed samples, the major FA was petroselinic acid 18:1(n‐12) which comprised more than 60 %; the contents of oleic and linoleic acids were lower (15–17 and 15–16 %, respectively). Earlier, a higher level (>80 %) of oleic acid had been reported for ginseng seeds. This discrepancy can be explained by an insufficient separation of these acids on standard columns used for GC of FAME. In general, seeds of wild and cultivated ginseng are very similar in lipid content and FA composition.  相似文献   

10.
Three minor ginsenosides, namely, ginsenoside Rh6 (1), vina-ginsenoside R4 (2) and vina-ginsenoside R13 (3), were isolated from the leaves of hydroponic Panax ginseng. The chemical structures were determined based on spectroscopic methods, including fast atom bombardment mass spectroscopy (FAB-MS), 1D-nuclear magnetic resonance (NMR), 2D-NMR, and, infrared (IR) spectroscopy. The melanogenic inhibitory activity of compounds 1, 2 and 3 was 23.9%, 27.8% and 35.2%, respectively, at a concentration of 80 µM. Likewise, the three compounds showed inhibitory activity on body pigmentation on a zebrafish model, which is commonly used as a model for biomedical or cosmetic research. These results from in vitro and in vivo systems suggest that the three aforementioned compounds isolated from Panax ginseng may have potential as new skin whitening compounds.  相似文献   

11.
12.
In this paper, the effects of peroxyl radical oxidation on the physicochemical and functional properties of walnut protein were investigated. Walnut protein isolate (WPI) containing 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH) was oxidatively stressed under aerobic conditions in peroxyl radical-generating media. Incubation of walnut protein with increasing concentration of AAPH resulted in gradual carbonyl generation and free sulfhydryl group degradation. The results of surface hydrophobicity implied that oxidation leads to protein aggregation thus decreasing protein solubility in an AAPH concentration-dependent manner (P < 0.05). Emulsifying properties exhibited a significant increase (P < 0.05) at AAPH concentrations up to 0.2 mM and higher AAPH concentrations reduced the emulsifying capacity of WPI. These results indicate that appropriate oxidation is helpful to improve the emulsifying properties of protein, and with an increase of oxidation degree, emulsifying functional will damage.  相似文献   

13.
The present study examined the antioxidant activity in heated canola oil of hexane, acetone, and methanol extracts of dry roots of gansu huangqin (Scutellaria rehderiana) as well as six flavonoids isolated from the acetone and methanol extracts. The oxidation was conducted at 95°C by monitoring oxygen consumption and decreases in both linoleic and α-linolenic acids. The acetone extract was most effective in inhibiting oxidation of canola oil, followed by the methanol extract. The antioxidant activity of gansu huangqin acetone extract was dose-dependent. Among the six flavonoids, baicalein and ganhuangenin were more effective than butylated hydroxytoluene (BHT) in protecting canola oil from oxidation. The present results suggest that the acetone extract of this root may be a potential source of natural antioxidants for use in processed foods.  相似文献   

14.
The seeds of two Apiaceae species, Ligusticum hultenii and Lomatium californicum, were investigated. Preliminary bioassays indicated that methylene chloride extracts of seeds of both species contained selective phytotoxic activity against monocots and antifungal activity against Colletotrichum fragariae. Active constituents were isolated by bioassay-guided fractionation, and the structures were elucidated by NMR and GC-MS as apiol and Z-ligustilide, isolated from L. hultenii and L. californicum, respectively. Apiol and Z-ligustilide had I50 values of about 80 and 600 μM, respectively, for inhibition of the growth of Lemna paucicostata. The methylene chloride (CH2Cl2) extracts of the seeds and the isolated and purified compounds were tested against the 2-methylisoborneol-producing cyanobacterium (blue-green alga) Oscillatoria perornata, and the green alga Selenastrum capricornutum. The CH2Cl2 extracts of both Apiaceae species and apiol were weakly toxic to both species of phytoplankton, while Z-ligustilide was toxic to both with a lowest complete inhibitory concentration (LCIC) of 53 μM. Seeds of L. californicum and L. hultenii were found to be rich sources of Z-ligustilide (97 mg/g of dry seed) and apiol (40 mg/g of dry seed), respectively.  相似文献   

15.
Apple replant is a widespread agricultural problem documented in all of the major fruit-growing regions of the world. In order to better understand the phytotoxic mechanisms induced by allelochemicals involved with this problem, Malus prunifolia plants were grown hydroponically to the six-leaf-stage in the presence of phthalic acid (0 or 1 mM) for 5, 10, or 15 days. Apple plants were evaluated for: shoot and root length, fresh and dry weight, malondialdehyde (MDA) content, hydrogen peroxide (H2O2) content, superoxide radical (O2 ·−) generation rate, and antioxidant enzyme activities. Shoot and root lengths and fresh and dry weights of M. prunifolia decreased in plants exposed to phthalic acid. MDA and H2O2 content increased in phthalic acid-treated plants as did the generation rate of O2 ·− in M. prunifolia roots. The activities of superoxide dismutase (EC 1.15.1.1), peroxidase (EC 1.11.1.7), catalase (EC 1.11.1.6), ascorbate peroxidase (EC 1.11.1.11), glutathione reductase (EC 1.6.4.2), dehydroascorbate reductase (EC 1.8.5.1), and monodehydroascorbate reductase (EC 1.6.5.4) increased in phthalic acid-stressed roots compared with control roots. These results suggest that activation of the antioxidant system by phthalic acid led to the formation of reactive oxygen species that resulted in cellular damage and the decrease of M. prunifolia growth.  相似文献   

16.
吴秀红  林炳昌 《化工学报》2007,58(9):2270-2275
制备色谱分离条件优化的基础是吸附等温线的测定及保留时间的预测。本文以人参皂甙Rg1、Re为研究对象,用色谱单柱制备了人参粗粉中的人参皂甙Rg1、Re,以迎头法测定了人参皂甙Rg1、Re在C18球形固定相中的吸附等温线,在竞争Langmuir模型基础上确定了吸附参数G和b,并应用非线性色谱理论的结果预测了人参皂甙Re的保留时间,上述结果与实验值进行了比较,平均相对误差为3.68%。在实验中发现了运用竞争Langmuir模型进行拟合的一些问题并进行了讨论。  相似文献   

17.
Brazilian Ginseng extracts of two species, Pfaffia paniculata and Pfaffia glomerata, were obtained by supercritical fluid extraction (SFE) with CO2 and by low-pressure solvent extraction (LPSE) with methanol, hexane and ethanol. The SFE assays were conducted at pressures of 100, 200 and 300 bar, and temperatures of 30 and 50 °C. The qualitative chemical compositions of the extracts were determined by thin layer chromatography (TLC). One of the active principles of interest from P. glomerata extract, β-ecdysone, was identified and quantified by HPLC. The antioxidant activities of Brazilian Ginseng extracts were determined by the coupled reaction of linolenic acid and β-carotene. For P. paniculata, the highest SFE yield was obtained at 200 bar/50 °C (0.22%, dry basis—d.b.), while the best extraction condition for P. glomerata was obtained at 200 bar/30 °C (0.18%, d.b.). The higher extract yields obtained by LPSE were 2.0% and 5.8% (w/w, d.b.) for P. paniculata and P. glomerata, respectively, both obtained with methanol as extraction solvent. From the overall extraction curve of P. glomerata, it was possible to obtain the kinetic parameters of extraction; the duration of the CER (constant extraction rate) period was determined as 134 min. The TLC plates showed the possible presence of flavonoids in the ethanolic extract for both Pfaffia species. The antioxidant activity analysis detected that LPSE extracts had higher activity than SFE extracts.  相似文献   

18.
Allelopathic effects of entire shoot extract, plant part extracts, and shoot residue of parthenium (Parthenium hysterophorus L.) on corn (Zea mays L.), ryegrass (Lolium multiflorum Lam.), wheat (Triticum aestivum L.), velvetleaf (Abutilon theophrasti Medik.), and soybean [Glycine max (L) Merr.] growth were examined. Parthenium shoot contained water-soluble materials that were toxic to root growth of velvetleaf and wheat. At 4% (w/ v) concentration, root growth of velvetleaf and wheat were reduced by 60 and 75%, respectively. The order of increasing sensitivity to parthenium was ryegrass, corn, wheat, and velvetleaf. There was a strong correlation between extract concentration and increased toxicity to test species. The toxicity of plant part extracts was also concentration dependent. At 1 and 2% (w/v), the inflorescence and leaves caused more root inhibition than stem extract. Parthenium shoot incorporated in soil at 1% (w/w) caused significantly more root inhibition of wheat than soybean, corn, and ryegrass. At 4% (w/w), root growth of all the test species was inhibited compared to the control. Toxicity of parthenium residue to wheat diminished with increasing periods of decomposition. Residue decomposed for four weeks was less toxic than the undecomposed residue.Florida Agricultural Experiment Stations Journal Series No. 7506.  相似文献   

19.
20.
Hydroxamic Acid Content and Toxicity of Rye at Selected Growth Stages   总被引:1,自引:0,他引:1  
Rye (Secale cereale L.) is an important cover crop that provides many benefits to cropping systems including weed and pest suppression resulting from allelopathic substances. Hydroxamic acids have been identified as allelopathic compounds in rye. This research was conducted to improve the methodology for quantifying hydroxamic acids and to determine the relationship between hydroxamic acid content and phytotoxicity of extracts of rye root and shoot tissue harvested at selected growth stages. Detection limits for an LC/MS-MS method for analysis of hydroxamic acids from crude aqueous extracts were better than have been reported previously. (2R)-2-β-d-Glucopyranosyloxy-4-hydroxy-(2H)-1,4-benzoxazin-3(4H)-one (DIBOA-G), 2,4-dihydroxy-(2H)-1,4-benzoxazin-3(4H)-one (DIBOA), benzoxazolin-2(3H)-one (BOA), and the methoxy-substituted form of these compounds, (2R)-2-β-d-glucopyranosyloxy-4-hydroxy-7-methoxy-(2H)-1,4-benzoxazin-3(4H)-one (DIMBOA glucose), 2,4-hydroxy-7-methoxy-(2H)-1,4-benzoxazin-3(4H)-one (DIMBOA), and 6-methoxy-benzoxazolin-2(3H)-one (MBOA), were all detected in rye tissue. DIBOA and BOA were prevalent in shoot tissue, whereas the methoxy-substituted compounds, DIMBOA glucose and MBOA, were prevalent in root tissue. Total hydroxamic acid concentration in rye tissue generally declined with age. Aqueous crude extracts of rye shoot tissue were more toxic than extracts of root tissue to lettuce (Lactuca sativa L.) and tomato (Lycopersicon esculentum Mill.) root length. Extracts of rye seedlings (Feekes growth stage 2) were most phytotoxic, but there was no pattern to the phytotoxicity of extracts of rye sampled at growth stages 4 to 10.5.4, and no correlation of hydroxamic acid content and phytotoxicity (I50 values). Analysis of dose–response model slope coefficients indicated a lack of parallelism among models for rye extracts from different growth stages, suggesting that phytotoxicity may be attributed to compounds with different modes of action at different stages. Hydroxamic acids may account for the phytoxicity of extracts derived from rye at early growth stages, but other compounds are probably responsible in later growth stages.  相似文献   

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