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1.
In this study, volatile oils of six Hawk tea varieties were studied for their chemical composition, antioxidant and antimicrobial activities to screen the most suitable botanical origins of Hawk tea. A total of 72 components were separated and identified from the six oils. The major constituents of the volatile oils were: α‐pinene, camphene, limonene, 1,8‐cineole, linalool, cis‐nerolidol, and germacrene B. Moreover, the volatile oils were evaluated for antioxidant potential and antimicrobial activities. The results showed that all volatile oils exhibited acceptable antioxidant and antimicrobial activities, which suggested that these volatile oils may serve as natural alternatives to synthetic antioxidants and preservatives to be applied in food and pharmaceutical industries. Principal component analysis results denoted that some major compounds may be closely related to the antioxidant and antimicrobial activities. It also showed that the volatile oils from Litsea coreana var. lanuginosa and Litsea pungens Hemsl . were characterized by positive values of first two principal components, indicating higher active chemical compounds and antioxidant and antimicrobial activities compared with other species. Thus, they were temporarily considered as good sources of Hawk tea.  相似文献   

2.
The present study is focused on the antioxidant capacity and chemical profiling of eight Croatian Satureja montana L. honey samples. Among the 20 compounds obtained by headspace solid‐phase microextraction (HS‐SPME) and identified by GC‐FID and GC/MS analyses, hotrienol was predominant (75.9–81.7%). The honey matrix volatile/semivolatile profile was investigated by ultrasonic solvent extraction (USE) followed by GC‐FID and GC/MS analyses. The major compounds identified by this latter method were the sinapic‐acid derivatives methyl syringate (36.2–72.8%) and syringaldehyde (2.2–43.1%). Direct, targeted HPLC‐DAD analyses of the native honey samples revealed the presence of methyl syringate (7.10–39.60 mg/kg) and syringic acid (0.10–1.70 mg/kg). In addition, the total phenolic content of the samples was determined by the Folin? Ciocalteu assay (311.0–465.9 mg GAE/kg), and the antioxidant capacity was evaluated by the DPPH radical‐scavenging activity (0.5–1.0 mmol TEAC/kg) and the ferric reducing antioxidant power (2.5–5.1 mmol Fe2+/kg).  相似文献   

3.
马缨丹叶片水提物与挥发油的生物活性及化学成分研究   总被引:13,自引:0,他引:13  
刘少群  贾正晖 《广西植物》2002,22(2):185-188
研究了马缨丹 ( Lantana camara L.)叶片水提物和挥发油水溶液的化感作用。结果表明 ,马缨丹叶片水溶物浓度在 0 .2 5 g FW m L- 1时 ,对所有受试植物的幼苗生长均有一定的抑制作用 ,浓度降至 0 .1 0 g FWm L- 1时 ,其抑制作用显著降低 ;马缨丹叶片挥发油水溶液在浓度为 1 0 0、2 0 0、30 0 μg m L- 1时 ,对受试植物均有很强的抑制作用 ,且具有明显的浓度效应。采用 GC/MS分析了马缨丹叶片挥发油的化学成分 ,鉴定了 1 9种化感物质 ,其中α-子丁香烯和β-子丁香烯为主要物质 ,分别占挥发油含量的 1 6 .2 9%、2 2 .2 9%。  相似文献   

4.
Phytochemicals, which are commonly found at different levels in many medicinal plants, are natural strong antioxidants used in traditional medicine. In this research, determination of differences of phytochemical compositions and biological properties were aimed as periodically (pre‐, full and post flowering) and daily (6 am, 1 pm and 8 pm) in Achillea gypsicola Hub.‐Mor . The volatile oils belonging to A. gypsicola were obtained by hydrodistillation and analyzed by gas chromatography‐flame ionization detection (GC‐FID) and gas chromatography‐mass spectrometry (GC/MS). The antimicrobial activities of the volatile oils were determined with disc diffusion method. The microdilution method was used to determine minimum inhibitory concentration (MIC). Total phenolic and flavonoid contents were determined by spectrophotometric methods and antioxidant capacities were evaluated by 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) free radical, reducing power (RP) and metal chelating activity (MCA) assay. In addition, the phenolic acid and flavonoid compositions were evaluated by reversed phase‐high‐performance liquid chromatography (RP‐HPLC). This study presented a comprehensive report for the first time on evaluation of the phytochemical composition and the biological properties of A. gypsicola at different phenological stages. Thirty‐two compounds, containing the major component as camphor, 1,8‐cineole and borneol, were detected. Designated harvest time for the highest yield of volatile oils was found to be at full flowering stage‐1 pm. It has been observed that the volatile oil composition changes periodically and even daily. Also, in this research, menthol and menthone were found as the composition of volatile oil in Achillea species for the first time. Full flowering stage was found as the richest period in terms of phenolic acid and flavonoid compositions of A. gypsicola for the first time. The species examined in this research showed a high antioxidant and antimicrobial activity in comparison to other studies with Achillea species. The volatile oils exhibited high performances with range of inhibition zones (8.3–42.3 mm) and minimum inhibitory concentration values (2.25—144 μg/ml). Besides, a high correlation between antioxidant activity and phenolic content of A. gypsicola was found. These results suggest that A. gypsicola can be used as a safe source in the cosmetic, food and pharmaceutical industries.  相似文献   

5.
We used (1)H-magnetic resonance spectroscopy to noninvasively determine total creatine (TCr), choline-containing compounds (Cho), and intracellular (IT) and extracellular (between-muscle fibers) triglycerides (ET) in three human skeletal muscles. Subjects' (n = 15 men) TCr concentrations in soleus [Sol; 100.2 +/- 8.3 (SE) mmol/kg dry wt] were lower (P < 0.05) than those in gastrocnemius (Gast; 125.3 +/- 9.2 mmol/kg dry wt) and tibialis anterior (TA; 123. 7 +/- 8.8 mmol/kg dry wt). The Cho levels in Sol (35.8 +/- 3.6 mmol/kg dry wt) and Gast (28.5 +/- 3.5 mmol/kg dry wt) were higher (P < 0.001 and P < 0.01, respectively) compared with TA (13.6 +/- 2. 4 mmol/kg dry wt). The IT values were found to be 44.8 +/- 4.6 and 36.5 +/- 4.2 mmol/kg dry wt in Sol and Gast, respectively. The IT values of TA (24.5 +/- 4.5 mmol/kg dry wt) were lower than those of Sol (P < 0.01) and Gast (P < 0.05). There were no differences in ET [116.0 +/- 11.2 (Sol), 119.1 +/- 18.5 (Gast), and 91.4 +/- 19.2 mmol/kg dry wt (TA)]. It is proposed that the differences in metabolite levels may be due to the differences in fiber-type composition and deposition of metabolites due to the adaptation of different muscles during locomotion.  相似文献   

6.
以甘肃省甘南藏族自治州碌曲县栽培和野生狭叶红景天为材料,分别对根茎(主根和侧根)的抗氧化能力、可溶性糖、总黄酮、酚类和红景天苷含量,以及挥发性组分进行研究.结果表明: 狭叶红景天栽培根茎的自由基抑制率(I)、铁离子还原/氧化能力(FRAP),以及可溶性糖、总黄酮、酚类和红景天苷含量均显著大于野生根茎;栽培和野生根茎中均含有21种挥发性组分,相对含量较高的为苯乙酮、2-糠醛、棕榈酸等;与野生根茎相比,栽培根茎有15种组分的相对含量增加,主根中相对变化量较大的为3-羟基月桂酸、2,4-二叔丁基苯酚、亚麻酰氯等,侧根为2-乙酰呋喃、对羟苯基乙醇、丁子香酚等.栽培和野生侧根的I、FRAP值,以及总黄酮、酚类和红景天苷含量均显著大于主根.与主根相比,侧根有12种挥发性组分相对含量增加,变化量较大的为3-羟基月桂酸、10,13-十八碳二炔酸甲酯、对羟苯基乙醇等.栽培驯化后狭叶红景天根茎的抗氧化能力、主要活性物质含量及挥发性组分相对含量高于野生狭叶红景天,且侧根的品质更佳.  相似文献   

7.
Eight men exercised at 66% of their maximal isometric force to fatigue after prior decrease in the glycogen store in one leg (low-glycogen, LG). The exercise was repeated with the contralateral leg (control) at the same relative intensity and for the same duration. Muscle (quadriceps femoris) glycogen content decreased in the LG leg from 199 +/- 17 (mean +/- S.E.M.) to 163 +/- 16 mmol of glucosyl units/kg dry wt. (P less than 0.05), and in the control leg from 311 +/- 23 to 270 +/- 18 mmol/kg (P less than 0.05). The decrease in glycogen corresponded to a similar accumulation of glycolytic intermediates. Muscle glucose increased in the LG leg during the contraction, from 1.8 +/- 0.1 to 4.3 +/- 0.6 mmol/kg dry wt. (P less than 0.01), whereas no significant increase occurred in the control leg (P greater than 0.05). It is concluded that during exercise glucose is formed from glycogen through the debranching enzyme when muscle glycogen is decreased to values below about 200 mmol/kg dry wt.  相似文献   

8.
火棘花挥发油化学成分的GC-MS分析及抗氧化活性研究   总被引:1,自引:0,他引:1  
采用水蒸气蒸馏法提取火棘花挥发油,利用气相色谱—质谱联用技术(GC-MS)分析其化学成分。使用维生素C和BHT为阳性对照,以DPPH自由基、亚硝酸钠清除作用为指标评价挥发油的抗氧化活性。从挥发油中鉴定了77个化合物,占挥发油总量的83.77%,含有多种生物活性成分,以萜类及其含氧衍生物(50.31%)、烷烃(18.52%)、醛(5.54%)为主;挥发油对DPPH自由基、亚硝酸钠有明显的清除作用,清除率为50%时,其体积分别为43.51、79.48μL,样品量与清除率间呈量效关系;挥发油对DPPH自由基的清除效果略低于1 mg·mL-1维生素C,对亚硝酸钠的清除效果优于1 mg·mL-1的BHT。  相似文献   

9.
This study was designed to examine the chemical composition and antioxidant activities of the volatile oils and methanol extracts of Olea europaea L. (cvs) chemlali and neb jmel stems. GC and GC–MS analyses of the volatile oils resulted in the identification of 38 and 35 compounds, representing 91.1 and 87.4 % of the volatile oils. Phenylethyl alcohol was found in the volatile oil of each cultivar, which was also the major volatile component of cv. chemlali and cv. neb jmel stems. Besides benzyl alcohol, methyl salicylate and 3-ethenylpyridine were the main volatile compounds of cv. chemlali, while nonanal, 3-ethenylpyridine and benzyl alcohol of cv. neb jmel stems were also the main constituents. Significant differences were also found in total tannin contents among two cultivars, representing 8.10 mg CEQ/g DW in cv. chemlali and 20.47 mg CEQ/g DW in cv. neb jmel. The highest contents of total phenols and o-diphenols were observed in stems extracts of cv. neb jmel (78.26, and 9.56 mg/100 g, respectively). The HPLC profiles for methanol extracts from stems of cv. chemlali and cv. neb jmel showed that oleuropein, vanillic acid and gallic acid were the predominant free phenolic compounds. Antioxidant activities of the volatile oils and the methanolic extract from stems parts were evaluated by DPPH and ABTS+ radical-scavenging activity assays. In all tests, methanolic extracts obtained from stems parts showed better antioxidant activity than volatile oils. Principal components analysis of the phenolics content and antioxidant activities showed discrimination between methanol extracts of the two cultivars.  相似文献   

10.
It has been suggested that insulin-induced suppression of endogenous glucose production (EGP) may be counteracted independently of increased epinephrine (Epi) or glucagon during moderate hypoglycemia. We examined EGP in nondiabetic (n = 12) and type 1 diabetic (DM1, n = 8) subjects while lowering plasma glucose (PG) from clamped euglycemia (5.6 mmol/l) to values just above the threshold for Epi and glucagon secretion (3.9 mmol/l). Individualized doses of insulin were infused to maintain euglycemia during pancreatic clamps by use of somatostatin (250 microg/h), glucagon (1.0 ng. kg(-1). min(-1)), and growth hormone (GH) (3.0 ng. kg(-1). min(-1)) infusions without need for exogenous glucose. Then, to achieve physiological hyperinsulinemia (HIns), insulin infusions were fixed at 20% above the rate previously determined for each subject. In nondiabetic subjects, PG was reduced from 5.4 +/- 0.1 mmol/l to 3.9 +/- 0.1 mmol/l in the experimental protocol, whereas it was held constant (5. 3 +/- 0.2 mmol/l and 5.5 mmol/l) in control studies. In the latter, EGP (estimated by [3-(3)H]glucose) fell to values 40% of basal (P < 0.01). In contrast, in the experimental protocol, at comparable HIns but with PG at 3.9 +/- 0.1 mmol/l, EGP was activated to values about twofold higher than in the euglycemic control (P < 0.01). In DM1 subjects, EGP failed to increase in the face of HIns and PG = 3.9 +/- 0.1 mmol/l. The decrease from basal EGP in DM1 subjects (4.4 +/- 1.0 micromol. kg(-1). min(-1)) was nearly twofold that in nondiabetics (2.5 +/- 0.8 micromol. kg(-1). min(-1), P < 0.02). When PG was lowered further to frank hypoglycemia ( approximately 3.1 mmol/l), the failure of EGP activation in DM1 subjects was even more profound but associated with a 50% lower plasma Epi response (P < 0. 02) compared with nondiabetics. We conclude that glucagon- or epinephrine-independent activation of EGP may accompany other counterregulatory mechanisms during mild hypoglycemia in humans and is impaired or absent in DM1.  相似文献   

11.
Rhus coriaria, also known as Sumac, has been traditionally used in many countries as spice, condiment, dying agent, and medicinal herb. The chemical composition of essential oils (EOs) and the volatile emissions from different organs of this species collected in Sicily (Italy) were analyzed by gas chromatography‐flame ionization detection and gas chromatography/mass spectrometry. Monoterpene and sesquiterpene hydrocarbons were the most abundant class in the volatile emissions with β‐caryophyllene and α‐pinene were the main constituents in the majority of the examined samples. The EO composition was characterized by high amount of monoterpene and sesquiterpene hydrocarbons together with diterpenes. The main compounds in the EO obtained from the leaves and both stages of fruit maturation were cembrene and β‐caryophyllene, while α‐pinene and tridecanoic acid were the key compounds in the flower EO. All the data were submitted to multivariate statistical analysis showing many differences among the different plant parts and their ontogenetic stages.  相似文献   

12.
The aim of this study was to compare the contents of the main biochemical compounds and the antioxidant capacity of five Spanish olive oils by four different antioxidant tests and to find out the most valuable oil for disease preventing diets. Fatty acids, sterols and individual antioxidant compounds in Arbequina, Hojiblanca, Extra Virgin, Picual and Lampante Spanish olive oils were determined. Antioxidant activities were done as well using different radical scavenging activities: total radical-trapping antioxidative potential by ABAP (TRAP-ABAP), radical scavenging activity by DPPH (RSA-DPPH), antioxidant assay by beta-carotene-linoleate model system (AA-beta-carotene) and total antioxidant status by ABTS (TAA-ABTS). The highest content of all studied antioxidant compounds (353; 329; 4.6 and 2.7 mg/kg for tocopherols, tocotrienols, polyphenols and o-diphenols, respectively) was found in Extra Virgin oil. Also the highest antioxidant capacity was observed in Extra Virgin oil (668 nM/ml; 29.4%; 40.4% and 2.64 mM TE/kg for TRAP-ABAP, RSA-DPPH, AA- beta-carotene and TAA-ABTS, respectively). The correlation between total phenols and antioxidant capacities measured by four methods was very high, but the highest for the beta-carotene (R = 0.9958). In conclusion, the best method for determination of the antioxidant capacity of olive oils is the beta-carotene test. Extra Virgin olive oil has high organoleptic properties and the highest antioxidant activity. The above-mentioned makes this oil a preferable choice for diseases preventing diets.  相似文献   

13.
Volatile constituents of Aristolochia argentina   总被引:1,自引:0,他引:1  
The essential oils from leaves, aerial stems and underground organs of Aristolochia argentina Gris., a medicinal plant popularly known as "charrúa", were obtained by hydrodistillation and analyzed by GC and GC/MS. Forty-three components were identified in the oils. All parts of the plant afforded volatile oils characterized by high levels of argentilactone (57-89%) and the presence of undecatriene isomers (0.3-4.0%), these latter compounds providing the essential oils and extracts with an intense particular odor. Terpenes account for the remaining portion of the essential oils (5-29%). Bicyclogermacrene predominates in the aerial parts of the plant, whereas ishwarane is the main terpene of the subterranean organs. Argentilactone, a suspected carcinogenic compound, was also identified in a medicinal commercial tincture of A. argentina.  相似文献   

14.
The composition of the volatile oils from the aerial parts of Hypericum perforatum L. collected in six localities from southeastern France was analysed by GC-MS. Twenty-nine to 41 compounds have been identified in these volatile oils. The main constituents were sesquiterpene hydrocarbons, and minor variations were pointed out in the oil composition among the six populations. However, the composition of all the analysed oils greatly varied from that of the previous studies, carried out on H. perforatum essential oils from other localities, in which monoterpenoids were the major constituents, particularly, the alpha-pinene.  相似文献   

15.
甘肃岷县当归不同药用部位挥发油的提取及其成分分析   总被引:1,自引:0,他引:1  
采用水蒸气蒸馏法分别提取产于甘肃岷县道地产区当归的当归身、当归尾、当归头中的挥发油,使用气相-质谱联用(GC-MS)分析其挥发油的化学组分.在相同提取测定条件下,当归不同部位提取的挥发油中各化学成分含量存在差异性,当归身、当归尾、当归头在保持较多藁本内酯的同时,均含有其他有效成分,且这些有效成分种类与含量不尽相同.提示当归不同药用部位的挥发油化学成分含量具有一定的差异,药理作用的物质基础不同,探寻当归不同部位的挥发油的化学成分变化规律,为中药当归的加工及临床应用提供科学依据.  相似文献   

16.
The responses of whole body, skeletal muscle, and plasma to oral K loading were studied in K-depleted male rats. Potassium depletion was induced by feeding the rats a K-deficient diet for 4 wk and injecting deoxycorticosterone acetate during the first week. After 4 wk, the rats were growth retarded and hypokalemic (1.9 mmol/l plasma) and had low whole-body and muscle K content, 188 +/- 27 and 276 +/- 19 mmol/kg fat-free dried tissue (FFDT), respectively, compared with 296 +/- 10 and 454 +/- 13 mmol/kg FFDT for the control group. Sodium and water retention also occurred in the K-deficient group. After K depletion, the rats were divided into four groups and received either 0, 1, 2, or 3 intragastric doses of 10 mmol KCl/kg at 8-h intervals. The rats were killed 8 h after the last dose. Control rats were treated similarly. K-depleted and control rats responded differently to K loading. In the normal rats, plasma K remained at 5.0 +/- 0.5 mmol/l, muscle K increased to 502 +/- 24 mmol/kg, and muscle K/N ratio increased from 3.0 to 3.4 mmol/g. In the K-depleted rats, plasma K increased to 7.2 +/- 0.7 mmol/l, muscle K increased to 453 +/- 50 mmol/kg, and muscle K/N ratio increased from 1.8 to 3.1 mmol/g. These data indicate that the capacity of the muscles to accumulate K was impaired after severe K depletion and caused elevated plasma K levels when repletion was complete.  相似文献   

17.
采用常压水蒸气蒸馏法提取竹枝细柄草(Capillipedium assimile (Steud.)A.Camus)花序的挥发油,经GC-MS分析,从花序挥发油中鉴定出45种化合物,占总油量的93.24%.其中含量较高的为4-十一烷酮(18.520%)、(E)-己酸-2-己烯酯(8.042%)、4-壬醇(7.778%)、...  相似文献   

18.
We tested the theory that links the capacity to perform prolonged exercise with the size of the muscle tricarboxylic acid (TCA) cycle intermediate (TCAI) pool. We hypothesized that endurance training would attenuate the exercise-induced increase in TCAI concentration ([TCAI]); however, the lower [TCAI] would not compromise cycle endurance capacity. Eight men (22 +/- 1 yr) cycled at approximately 80% of initial peak oxygen uptake before and after 7 wk of training (1 h/day, 5 days/wk). Biopsies (vastus lateralis) were obtained during both trials at rest, after 5 min, and at the point of exhaustion during the pretraining trial (42 +/- 6 min). A biopsy was also obtained at the end of exercise during the posttraining trial (91 +/- 6 min). In addition to improved performance, training increased (P < 0.05) peak oxygen uptake and citrate synthase maximal activity. The sum of four measured TCAI was similar between trials at rest but lower after 5 min of exercise posttraining [2.7 +/- 0.2 vs. 4.3 +/- 0.2 mmol/kg dry wt (P < 0.05)]. There was a clear dissociation between [TCAI] and endurance capacity because the [TCAI] at the point of exhaustion during the pretraining trial was not different between trials (posttraining: 2.9 +/- 0.2 vs. pretraining: 3.5 +/- 0.2 mmol/kg dry wt), and yet cycle endurance time more than doubled in the posttraining trial. Training also attenuated the exercise-induced decrease in glutamate concentration (posttraining: 4.5 +/- 0.7 vs. pretraining: 7.7 +/- 0.6 mmol/kg dry wt) and increase in alanine concentration (posttraining: 3.3 +/- 0.2 vs. pretraining: 5.6 +/- 0.3 mmol/kg dry wt; P < 0.05), which is consistent with reduced carbon flux through alanine aminotransferase. We conclude that, after aerobic training, cycle endurance capacity is not limited by a decrease in muscle [TCAI].  相似文献   

19.
Regional differences in the content of intramyocellular lipids (IMCL), extramyocellular lipids, and total creatine (TCr) were quantified in soleus (S), tibialis posterior (TP), and tibialis anterior (TA) muscles in humans using in vivo 1H proton spectroscopic imaging at 4 T. Improved spatial resolution (0.25-ml nominal voxel resolution) made it feasible to measure IMCL in S, TP, and TA simultaneously in vivo. The most significant regional difference was found in the content of IMCL compared with extramyocellular lipids or TCr. The concentrations of TCr were found to be 29-32 mmol/kg, with little regional variation. IMCL content was measured to be 4.8 +/- 1.6 mmol/kg tissue wt in S, 2.8 +/- 1.3 mmol/kg tissue wt in TP, and 1.6 +/- 0.9 mmol/kg tissue wt in TA in the order of S > TP > TA (P < 0.05). It is likely that these IMCL values are consistent with the known fiber types of these muscles, with S having the greatest fraction of type I (slow-twitch, oxidative) fibers and TA having a large fraction of type IIb (fast-twitch, glycolytic) fibers.  相似文献   

20.
This study is designed to examine the chemical composition and in vitro antioxidant activity of the essential oil and sub-fractions of the methanol extract of Marrubium globosum subsp. globosum. The GC and GC-MS analysis of the essential oil were resulted in the determination of 84 components representing 88.2% of the oil. The major constituents of the oil were spathulenol (15.8%), beta-caryophyllene (9.0%), caryophyllene oxide (7.9%), germacrene D (6.5%), and bicyclogermacrene (3.1%). Antioxidant activities of the samples were determined by three different test systems namely DPPH, beta-carotene/linoleic acid and reducing power assay. In DPPH system, the weakest radical scavenging activity was exhibited by the essential oil (1203.38+/-7.18 microg ml(-1)). Antioxidant activity of the polar sub-fraction of methanol extract was superior to the all samples tested with an EC(50) value of 157.26+/-1.12 microg ml(-1). In the second case, the inhibition capacity (%) of the polar sub-fraction of methanol extract (97.39%+/-0.84) was found the strongest one, which is almost equal to the inhibition capacity of positive control BHT (97.44%+/-0.74). In the case of reducing power assay, a similar activity pattern was observed as given in the first two systems. Polar sub-fraction was the strongest radical reducer when compared with the non-polar one, with an EC(50) value of 625.63+/-1.02 microg ml(-1). The amount of the total phenolics was highest in polar sub-fraction (25.60+/-0.74 microg/mg). A positive correlation was observed between the antioxidant activity potential and total phenolic level of the extracts. On the other hand, total flavonoid content was found equal for the both sub-fractions.  相似文献   

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