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1.
The distribution of seven flavonoids, eriocitrin, luteolin 3'-O-beta-d-glucuronide, hesperidin, diosmin, isoscutellarein 7-O-glucoside, hispidulin 7-O-glucoside, and genkwanin, has been studied in Rosmarinus officinalis leaves, flowers, stems, and roots during plant growth. The maximum level reached by luteolin 3'-O-beta-d-glucuronide in leaves during June-August suggests the existence of a delay between the activation of the enzymes involved in the flavanone and flavone biosynthesis. The presence of hesperidin and diosmin in the vascular system is significant, and hesperidin shows even higher levels than the phenolic diterpenes and rosmarinic acid. The distribution of flavonoids observed in R. officinalis suggests a functional and structural relationship between phytoregulators and flavonoids, where flavonoids would be "protectors" of the activity of phytoregulators. A hypothesis for the general pathway of biosynthesis of these compounds in plants of the family Labiatae is proposed.  相似文献   

2.
The headspace volatile components of roots, stems, leaves, and flowers of Echinacea angustifolia,E. pallida, and E. purpurea were analyzed by capillary gas chromatography/mass spectrometry (GC/MS). Over 70 compounds were identified in the samples. All plant tissues, irrespective of the species, contain acetaldehyde, dimethyl sulfide, camphene, hexanal, beta-pinene, and limonene. The main headspace constituents of the aerial parts of the plant are beta-myrcene, alpha-pinene, limonene, camphene, beta-pinene, trans-ocimene, 3-hexen-1-ol, and 2-methyl-4-pentenal. The major headspace components of root tissue are alpha-phellandrene (present only in the roots of E. purpurea and E.angustifolia), dimethyl sulfide, 2-methylbutanal, 3-methylbutanal, 2-methylpropanal, acetaldehyde, camphene, 2-propanal, and limonene. Aldehydes, particularly butanals and propanals, make up 41-57% of the headspace of root tissue, 19-29% of the headspace of the leaf tissue, and only 6-14% of the headspace of flower and stem tissues. Terpenoids including alpha- and beta-pinene, beta-myrcene, ocimene, limonene, camphene, and terpinene make up 81-91% of the headspace of flowers and stems, 46-58% of the headspace of the leaf tissue, and only 6-21% of the roots. Of the 70 compounds identified, >50 are reported in Echinacea for the first time.  相似文献   

3.
Rosemary (Rosmarinus officinalis) leaves possess a variety of bioactivities. Previous studies have shown that the extract of rosemary leaves from supercritical fluid extraction inhibits the expression of inflammatory mediators with apparent dose-dependent responses. In this study, three different extraction conditions (5000 psi at 40, 60, and 80 °C) of supercritical carbon dioxide (SC-CO(2)) toward the extraction of antioxidants from rosemary were investigated. Furthermore, simultaneous comparison of the anti-inflammatory properties between rosemary extract prepared from SC-CO(2) under optimal conditions (5,000 psi and 80 °C) and its purified carnosic acid (CA) using lipopolysaccharide (LPS)-treated murine RAW 264.7 macrophage cells was also presented. Results showed that the yield of 3.92% and total phenolics of 213.5 mg/g extract obtained from the most effective extraction conditions showed a high inhibitory effect on lipid peroxidation (IC(50) 33.4 μg/mL). Both the SC-CO(2) extract and CA markedly suppressed the LPS-induced production of nitric oxide (NO) and tumor necrosis factor-α (TNF-α), as well as the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), phosphorylated inhibitor-kappaB (P-IκB), and nuclear factor-kappaB (NF-κB)/p65 in a dose-dependent manner. The five major compounds of verbenone, cirsimaritin, salvigenin, carnosol, and CA existing in the SC-CO(2) extract were isolated by semipreparative HPLC and identified by HPLC-MS/MS analysis. CA was the most abundant recorded compound and the most important photochemical with an anti-inflammatory effect with an IC(50) of 22.5 μM or 7.47 μg/mL presented to the best inhibitory activity on NO production better than that of the 14.50 μg/mL dosage prepared from the SC-CO(2) extract. Nevertheless, the effective inhibition of LPS-induced NF-κB signaling in RAW 264.7 cells from the SC-CO(2) extract extends the potential application of nutraceutical formulation for the prevention of inflammatory diseases.  相似文献   

4.
5.
Antioxidative compounds were isolated from the 50% methanol extract of dried leaves of Celastrus hindsii. Eight phenolic compounds (1-8) were finally obtained by reversed-phase high-performance liquid chromatography, and their structures were elucidated by nuclear magnetic resonance spectrometry and mass spectrometry analyses. They were the five known compounds, rutin (1), kaempferol 3-rutinoside (2), rosmarinic acid (3), lithospermic acid (4), and lithospermic acid B (6), and three novel oligomers of rosmarinic acid, a dimer (5) and two trimers (7 and 8). The major components in the extract were rosmarinic acid (3) and lithospermic acid B (6). These phenolic compounds were shown to have antioxidative activities against the autoxidation of methyl linoleate in bulk phase and the radical-initiated peroxidation of soybean phosphatidylcholine in liposomes. In the liposomal peroxidation, the number of phenolic hydroxyl group in each molecule was correlated with the effectiveness of antioxidative activity.  相似文献   

6.
The chemical composition of the essential oil of the Sardinian Rosmarinus officinalis L. obtained by hydro distillation and steam\hydro distillation was studied using GC-FID and MS. Samples were collected at different latitude and longitude of Sardinia (Italy). The yields ranged between 1.75 and 0.48% (v/w, volume/dry-weight). A total of 30 components were identified. The major compounds in the essential oil were alpha-pinene, borneol, (-) camphene, camphor, verbenone, and bornyl-acetate. Multivariate analysis carried out on chemical molecular markers, with the appraisal of chemical, pedological, and random amplified polymorphic DNA data, allows four different clusters to be distinguished. The antimicrobial and antifungal tests showed a weak activity of Sardinian rosemary. On the other hand, an inductive effect on fungal growth, especially toward Fusarium graminearum was observed.  相似文献   

7.
施磷对苜蓿光合产物在根茎叶的分配及抗蓟马的影响   总被引:1,自引:0,他引:1  
为了明确施磷后紫花苜蓿根、茎、叶中光合产物分配与苜蓿抗蓟马能力的关系,本试验以紫花苜感虫品种‘甘农3号’和抗虫品种‘甘农9号’为材料,以北方苜蓿蓟马类优势害虫牛角花齿蓟马(Odontothripsloti)为研究对象,设0mg(P_2O_5)·kg~(-1)(土)、27mg(P_2O_5)·kg~(-1)(土)、54mg(P_2O_5)·kg~(-1)(土)、81mg(P_2O_5)·kg~(-1)(土)和108mg(P_2O_5)·kg~(-1)(土)5个磷水平,分别记为P0、P1、P2、P3和P4,在苜蓿6叶期,按3头·株~(-1)接入牛角花齿蓟马,分别于苜蓿持续受害7 d、14 d和21 d时,评价苜蓿的受害指数,测量单株叶、茎、根生物量和根、茎、叶中的可溶性糖和淀粉含量。结果表明:随着施磷水平的升高,‘甘农3号’和‘甘农9号’苜蓿的受害指数降低,总体以P3水平下最低;受害7 d时,两个苜蓿品种受害指数均下降但不显著;受害14 d和21 d时受害指数下降显著(P0.05)。施磷后苜蓿根、茎和叶生物量均显著增加,在蓟马为害前期(7d)和中期(14d)苜蓿受害较轻时,生物量向叶中分配较多;在受到持续较重的为害后(21d),苜蓿的生物量更多向根系分配,相应分配到叶部的生物量有所下降,茎秆中的生物量分配比例变化不显著。相对于‘甘农3号’,各施磷水平下‘甘农9号’分配到叶中的生物量更多。施磷后苜蓿根、茎和叶中可溶性糖和淀粉含量显著增加,随着受害时间的持续,苜蓿根、茎和叶中的淀粉含量总体下降,而可溶性糖含量持续增加;在受害14 d和21 d时,‘甘农9号’的叶和根中的可溶性糖及淀粉含量明显高于‘甘农3号’。总之,施磷可有效增强苜蓿对蓟马的耐害性,在虫害压力适中时,施磷促进了苜蓿地上部分的补偿生长,虫害压力较大时,施磷保证根系的生长以维持其生存。随着受害时间的持续,苜蓿存贮型碳水化合物淀粉的含量趋向减少,根、茎和叶中的可溶性糖含量升高,使较多的资源用于苜蓿光合器官和贮藏器官的构建。P3水平[81 mg(P_2O_5)·kg~(-1)(土)]为本试验中苜蓿最佳施磷水平。  相似文献   

8.
山西省水土流失面积10万平方公里,占总面积的64.1%。水土流失使土地生产力降低,水库淤积,河床抬高,水旱灾害频繁。根据当地的自然条件,建设“五层楼”的结构模式,修成水平梯田294公顷,造林906.4公顷,种草154.5公顷,取得了明显的经济效益和生态效益。开发山区的出路在于大力植树种草,发展畜牧业,加强农田基本建设,保证粮食稳产增收。治理小流域,必须建设基本农田粮食基地和多种经营商品基地,积极发展种植业。要注意解决边治理边破坏的问题。  相似文献   

9.
植物器官的氮磷比(N/P)可以揭示植物生长发育过程的营养平衡。深松耕作为黄土高原半干旱区一种较好的农田耕作方法被广泛应用,尽管已被证实深松耕可以提高作物产量和地上生物量,但深松耕是否影响作物器官N/P及从作物器官N/P角度能否解释地上生物量增加的机制尚有待进一步研究。该研究于2016-2018年在黄土高原区设置了不同耕作方法(深松耕、旋耕、翻耕和免耕)和施氮量(基肥200 kg/hm2、基肥200 kg/hm2+拔节期肥100 kg/hm2)的田间裂区试验,研究了不同处理对玉米地上生物量、不同器官(根、茎和叶)中N/P的影响以及其N/P与地上生物量的关系。结果表明:1)相比翻耕、免耕,深松耕能显著提高地上生物量(P<0.05),2016和2018年深松耕的地上生物量比翻耕、免耕分别提高了9.56%、9.29%和4.67%、5.94%;2)相比翻耕、免耕,深松耕和旋耕均能显著降低根、叶的N/P(P<0.05),深松耕的根、叶N/P分别为19.90、17.74,降幅最大;施肥措施及耕作方法与施肥措施的交互作用对根、茎和叶的N/P无显著影响;3)通过结构方程模型分析发现,耕作方法通过影响根和叶N/P,间接影响地上生物量,效应值分别为0.10和0.14,耕作方法对地上生物量无直接显著影响,说明根和叶的N/P是影响地上生物量的两个重要的间接因素;通过线性混合效应模型分析得出,地上生物量与根、叶N/P呈显著负相关关系,与茎N/P无相关性。研究表明,深松耕通过降低玉米根和叶N/P、促进植物氮磷营养平衡的生态策略来提高地上生物量。研究结果对进一步揭示耕作与施肥对玉米生产与农田生态系统氮磷平衡的影响机制具有一定的借鉴意义。  相似文献   

10.
Methods were developed to identify and select accessions of rosemary, Rosmarinus officinalis (L.), producing optimum antioxidant activity. Extracts from 12 different rosemary accessions, using three solvents of varying polarity, were assayed for their antioxidant activity, and their major antioxidant compounds were identified and quantified by high-performance liquid chromatography (HPLC). Carnosic acid concentrations were correlated with (i) the free radical scavenging activity of these extracts, as measured by the 2,2-diphenyl-1-picrylhydrazyl assay (adjusted R(2) = 77.3%) and (ii) their inhibition of linoleic acid oxidation, as measured by the beta-carotene assay (adjusted R(2) = 44.1%). The correlation was broadly confirmed by the production of volatile aldehydes as measured by the hexanal assay. The variation of carnosic acid concentrations in extracts of 29 accessions, grown in field trials at three sites in England, was determined.  相似文献   

11.
Volatile extracts were isolated from dried medicinal plants [Angelica tenuissimae roots (AT, Angelica tenuissima Nakai), peppermint leaves (PL, Mentha arvensis L.), pine needles (PN, Pinus sylvestris L.), and sweet flag leaves (SF, Acorus gramineus Rhizoma)] using steam distillation under reduced pressure, followed by continuous liquid-liquid extraction (DRP-LLE). The extracts were then analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The major volatile constituents of AT, PL, PN, and SF were 3-butylidene-4,5-dihydrophthalide (32 mg/g), menthol (18 mg/g), thunbergol (2.1 mg/g), and cis-asarone (37 mg/g), respectively. The inhibitory activity (%) of the extracts against hexanal oxidation ranged from 33 to 98% at a level of 50 microg/mL. Among the volatile extracts, PL and PN increased cell viabilities by 10 and 24%, respectively, at a dose of 1 microg/mL, compared to that of H2O2-treated brain neuroblastoma cells, SK-N-SH. However, a 20% reduction in the malonaldehyde level, an index for lipid peroxidation, was observed at only 1 microg/mL concentration of PN.  相似文献   

12.
Essential oils from the stems/leaves (L) and flowers (F) of Lavandula stoechas L. ssp. stoechas growing wild in southern Sardinia (Italy) were extracted by hydrodistillation and analyzed by gas chromatography coupled with flame ionization detector and ion trap mass spectrometry. The major compound was fenchone, accounting for, on average, 52.60% in L and 66.20% in F, followed by camphor (13.13% versus 27.08%, in L and F, respectively). F essential oil yields (volume per dry weight) decreased from the beginning to the end of the flowering stage, whereas L yields remained constant during the year. The nine main compounds derived from two different subpathways, A and B. The compounds that belong to the same subpathway showed a similar behavior during the year. The essential oils were tested for their antifungal activity using the paper disk diffusion method. The essential oils tested were effective on the inactivation of Rhizoctonia solani and Fusarium oxysporum and less effective against Aspergillus flavus. Among the single compounds tested, fenchone, limonene, and myrtenal appeared to be the more effective on the inhibition of R. solani growth.  相似文献   

13.
Potato plants synthesize phenolic compounds as protection against bruising and injury from bacteria, fungi, viruses, and insects. Because antioxidative phenolic compounds are also reported to participate in enzymatic browning reactions and to exhibit health-promoting effects in humans, a need exists for accurate methods to measure their content in fresh and processed potatoes. To contribute to our knowledge about the levels of phenolic compounds in potatoes, we validated and used high-performance liquid chromatography and liquid chromatography/mass spectrometry to measure levels of chlorogenic acid, a chlorogenic isomer, and caffeic acid in flowers, leaves, stems, and tubers of the potato plant and in home-processed potatoes. The total phenolic acid content of flowers (626 mg/100 g fresh wt) was 21 and 59 times greater than that of leaves and stems, respectively. For all samples, chlorogenic acid and its isomer contributed 96-98% to the total. Total phenolic acid levels (in g/100 g fresh wt) of peels of five potato varieties grown in Korea ranged from 6.5 to 42.1 and of the flesh (pulp) from 0.5 to 16.5, with peel/pulp ratios ranging from 2.6 to 21.1. The total phenolic acid content for 25 American potatoes ranged from 1.0 to 172. The highest amounts were present in red and purple potatoes. Home processing of pulp with various forms of heat induced reductions in the phenolic content. The described methodology should facilitate future studies on the role of potato phenolic compounds in the plant and the diet.  相似文献   

14.
Gossypol is an allelochemical that occurs naturally throughout the cotton plant as an enantiomeric mixture. Gossypol and related terpenoids protect the plant from some insect herbivores. Cottonseed has a high protein content, but it is underutilized because (-)-gossypol, which is toxic to nonruminants, occurs in the seed along with (+)-gossypol. Commercial Upland cottons usually have an approximate 3:2 (+)- to (-)-gossypol ratio in the seed, but plants can be bred with <8% (-)-gossypol using accessions of Gossypium hirsutum var. marie galante as parents. We report the (+)- and (-)-gossypol ratios and the concentration of related terpenoids in the stems, leaves, and roots of four accessions of marie galante that show high, moderate, and near normal levels of (+)-gossypol in the seed; we compare these values to the commercial cultivar Stoneville 474, which has 62% (+)-gossypol in the seed. In the marie galante accessions 2452 and 2425 that have the highest levels of (+)-gossypol in the seed, the percent (+)-gossypol and the concentration of gossypol and the related terpenoids were significantly higher (P = 0.05) in the stems and leaves as compared to Stoneville 474. Our analysis indicates that progeny from accessions 2452 and 2425 that retain these traits should not be overly susceptible to herbivorous insects.  相似文献   

15.
In this study, the essential oil and the phenolic composition along with the antioxidant activity of R. officinalis L. and S. fruticosa Miller, collected in Zakynthos island (Ionian Sea, Greece), were investigated. The essential oil composition of the plants was characterized by the presence of 1,8-cineole. Mean values of the antioxidant activities of rosemary and sage essential oils indicated slight differences. The antioxidant activity of sage oil was correlated with the oxygenated sesquiterpenes and diterpenes concentrations. Concerning the methanolic extracts, a close relationship between the phenolic content and the development stage during vegetative cycle of these plants was observed. The identified flavonoids, except rutin, seemed to increase with the advancement of developmental stages, while phenolic acids followed an opposite pattern. The antioxidant activity was correlated with the amount of total phenolic content.  相似文献   

16.
The antioxidant activity of 3-dehydroshikimic acid (DHS), an intermediate in the biosynthesis of aromatic amino acids, was evaluated in three assay systems: bulk oil (lard), liposomes, and a 10% corn oil-in-water emulsion. Upon initiation of peroxidation in the liposome or emulsion systems, DHS exhibited weak antioxidant activity. In contrast, DHS displayed strong antioxidant activity in lard, suppressing peroxidation with activity comparable to that of tert-butylhydroquinone, propyl gallate, and gallic acid and superior to that of alpha-tocopherol. Two major DHS oxidation products, gallic acid and protocatechuic acid, were identified by gas chromatography/mass spectral analysis of lard extracts; both compounds are effective antioxidants in the bulk oil system. In the liposome system, DHS remained intact throughout the assay period. A small amount of gallic acid was observed in extracts of the emulsion; however, protocatechuic acid was not detected. A mechanism to explain the different activities of DHS in the three lipid systems is proposed.  相似文献   

17.
Fruits and leaves from different cultivars of thornless blackberry (Rubus sp.), red raspberry (Rubus idaeus L.), black raspberry (Rubus occidentalis L.), and strawberry (Fragaria x ananassa D.) plants were analyzed for total antioxidant capacity (oxygen radical absorbance capacity, ORAC) and total phenolic content. In addition, fruits were analyzed for total anthocyanin content. Blackberries and strawberries had the highest ORAC values during the green stages, whereas red raspberries had the highest ORAC activity at the ripe stage. Total anthocyanin content increased with maturity for all three species of fruits. Compared with fruits, leaves were found to have higher ORAC values. In fruits, ORAC values ranged from 7.8 to 33.7 micromol of Trolox equivalents (TE)/g of fresh berries (35. 0-162.1 micromol of TE/g of dry matter), whereas in leaves, ORAC values ranged from 69.7 to 182.2 micromol of TE/g of fresh leaves (205.0-728.8 micromol of TE/g of dry matter). As the leaves become older, the ORAC values and total phenolic contents decreased. The results showed a linear correlation between total phenolic content and ORAC activity for fruits and leaves. For ripe berries, a linear relationship existed between ORAC values and anthocyanin content. Of the ripe fruits tested, on the basis of wet weight of fruit, cv. Jewel black raspberry and blackberries may be the richest source for antioxidants. On the basis of the dry weight of fruit, strawberries had the highest ORAC activity followed by black raspberries (cv. Jewel), blackberries, and red raspberries.  相似文献   

18.
Water-treated maize stems were subjected to delignification with peroxymonosulfuric acid at 20 degrees C for 144 h, with peroxyformic acid at 80 degrees C for 6 h, with peracetic acid at 50 degrees C for 6 h, and with 2% hydrogen peroxide at 45 degrees C for 12 h at pH 1.5, 4.4, 9.5, 11.5, 12.0, and 12.6, respectively, which solubilized 47.1, 91.3, 33.3, 16.6, 15.9, 17.4, 86.2, 87.7, and 91. 3% of the original lignin, respectively. Substantial lignins were released during the treatment with peroxyformic acid and hydrogen peroxide at pH > or =11.5, whereas an insignificant effect on delignification was observed by using peroxymonosulfuric acid, peracetic acid, and hydrogen peroxide under acidic, natural, and weakly alkaline media conditions. The structures of the isolated lignin preparations were investigated by chemical analysis, gel permeation chromatography, and UV, FT-IR, and (13)C NMR spectroscopy.  相似文献   

19.
The roots of Rumex bucephalophorus, collected in Israel, were analyzed for trans-stilbenes. Two stilbene-O-glycosyl derivatives were identified, in addition to 3,5,4'-trihydroxystilbene (1) (resveratrol). The stilbene-O-glycosyl derivatives were 5,4'-dihydroxystilbene-3-O-beta-d-glucopyranoside (2) (piceid) and the new 5,4'-dihydroxystilbene-3-O-alpha-arabinopyranoside (3), which is being named rumexoid. The structure of rumexoid was elucidated by using spectroscopic data. The antioxidant capacities of stilbenoids 1-3 were determined and expressed as trolox equivalent antioxidant capacity (TEAC). TEAC value for trans-resveratrol was highest (2.7) and for rumexoid lowest (1.5). In vitro, trans-resveratrol and rumexoid demonstrated a potent inhibitory effect on alpha-glucosidase activity (IC50 < 0.1 and < 0.5 mM, respectively). The commercial antidiabetic agent acarbose was shown to inhibit only 35% of the enzyme activity at 0.5 mM. The addition of piceid to the reaction mixture did not inhibit alpha-glucosidase in vitro in the range of concentrations used. These findings extend the range of reported beneficial effects of stilbene derivatives, and demonstrate the multifaceted activities that dietary polyphenols may exert in the intestine, where their concentrations are highest in the body.  相似文献   

20.
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