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1.
Studies were made on the protein solubility of deoiled jute (Corchorus olitorius, Linn.) seed in aqueous solution over various pHs and in different concentrations of NaCl at pH 8.0. Chemical analysis of the seed protein showed 16 amino acids, of which 9 were essential. Gel filtration on Sephadex G-200 revealed the presence of four components, and their molecular weights were determined by two standard methods. Extractable jute seed proteins in salt solution were separated into six fractions electrophoretically (SDS-PAGE). The molecular weights of the six fractions were found to be 118,000; 103,000; 96,000; 67,500; 48,500; and 15,000.  相似文献   

2.
Two furanochromones and one furanochromone glycoside were isolated from the fruits of Ammi visnaga (L.) Lam. They were identified as khellin, visnagin, and khellol glycoside by interpretation of spectral analyses. Quantitative determination of furanochromones in A. visnaga (L.) ripe fruits from Hatay region (Turkey) was carried out by ultraviolet spectrophotometry and gas chromatography. In addition, photochemical properties of furanochromones and chemical composition of essential oil were determined.  相似文献   

3.
Ruta chalepensis is a rich source of important secondary metabolites such as furanocoumarins and alkaloids. Besides, it is a medicinal plant and still used in traditional medicine. For that reason, its chemical composition, medicinal properties, and uses were reviewed in this article.  相似文献   

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5.
The use of a reagent containing copper (II), bicinchoninic acid (BCA) and tartrate buffered at pH 11.25 was studied voltammetrically, coulometrically, spectrophotometrically and chemically. The reagent exhibits three cathodic waves at rotating platinum disk and rotating glassy carbon electrodes. The two more-positive cathodic waves correspond to electrochemical reduction to copper (I)-bisbicinchoninate, Cu(BCA)23?. The third cathodic wave is caused by reduction to metallic copper. A reaction mechanism is proposed that shows the major chemical species in the solution and the electrochemical reaction products. Voltammetric and chemical studies indicate that the reagent should be used with care for protein assays because it is subject to multiple chemical interferences.  相似文献   

6.
In this investigation, the chemical compositions of berries from sea buckthorn were studied. The amount of ascorbic acid and β-carotene determined by HPLC was 170 mg/100 g FW and 0.20 mg/g FW, respectively. Total phenols, anthocyanins, acidity and total soluble solids (TSS) contents were 247 mg GAE/100 g FW, 3 mg/L (cyanidin-3-glucoside), 5.32% and 13.8%, respectively. Fruit antioxidant activity determined by the ferric reducing ability of plasma (FRAP) method was 24.85 mM Fe/100 g FW. Results confirmed the presence of six dominant fatty acids (determined by GC) in fruit including linoleic (34.2%), palmitoleic (21.37%), palmitic (17.2%), oleic (12.8%), linolenic (5.37%) and stearic acid (1.67%). Five dominant fatty acids of the seeds were linoleic (42.36%), linolenic (21.27%), oleic (21.34%), palmitic (6.54%) and stearic acid (2.54%). The nitrogen content was 3.96%. The P, K, Ca, Mg, Fe, Zn, Mn, Cu, Cd and Cl contents of fruit were 491, 1674, 1290, 990, 291, 29.77, 108.37, 17.87, 0.021 and 2.18 mg/kg DW, respectively.  相似文献   

7.
《Analytical letters》2012,45(5):895-907
Abstract

An amperometric biosensor for the determination of phenols is proposed using a crude extract of sweet potato (Ipomoea batatas (L.) Lam.) as an enzymatic source of polyphenol oxidase (PPO; tyrosinase; catechol oxidase; EC 1.14.18.1). The biosensor is constructed by the immobilization of sweet potato crude extract with glutaraldehyde and bovine serum albumin onto an oxygen membrane. This biosensor provides a linear response for catechol, pyrogallol, phenol and p-cresol in the concentration ranges of 2.0×10?5-4.3×10?4mol L?1, 2.0×10?5-4.3×10?4 mol L?1, 2.0×10?5-4.5×10?4 mol L?1 and 2.0×10?5-4.5×10?4mol L?1, respectively. The response time was about 3–5 min for the useful response range, and the lifetime of this electrode was excellent for fifteen days (over 220 determinations for each enzymatic membrane). Application of this biosensor for the determination of phenols in industrial wastewaters is presented.  相似文献   

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To test seed lots of tomato F1 hybrid varieties for the presence of undesirable inbred seeds by electrophoresis, a method has been developed on the basis of ultrathin-layer isoelectric focusing. The method is based on the genetic variation of the seed protein PRS-1 which could be visualized by isoelectric focusing of a 5 mM NaCl-soluble seed protein extract in a pH 6-9 gel followed by protein staining. Two genetic variants of the PRS-1 protein, PRS-1+ and PRS-1(1), were found among open-pollinated varieties, as well as among F1 hybrid varieties. The isoelectric points (pI) of the PRS-1 proteins are 7.1 and 6.1 for PRS-1+ and PRS-1(1), respectively. The PRS-1 protein is unique to seed tissue and is located primarily in the embryo. A genetic 1:2:1 segregation of the gene Prs-1 among several F2 populations shows monogenic inheritance. Analysis of commercial F1 hybrid varieties from several seed companies indicated that the Prs-1(1) allele, in contrast to the Prs-1+ allele, is primarily present in gene pools of "Money-maker type" tomatoes. The described method is generally applicable to all tomato F1 varieties that are heterozygous for the gene Prs-1. With the described method one person can routinely analyze more than 768 seeds per day.  相似文献   

10.
Rapeseed (Brassica napus L.) is a herbaceous annual plant of the Cruciferous family, the Cabbage genus. This oilseed crop is widely used in many areas of industry and agriculture. High-quality oil obtained from rapeseed can be found in many industrial food products. To date, extracts with a high content of biologically active substances are obtained from rapeseed using modern extraction methods. Brassica napus L. seeds contain polyunsaturated and monounsaturated fatty acids, carotenoids, phytosterols, flavonoids, vitamins, glucosinolates and microelements. The data in this review show that rapeseed biocompounds have therapeutic effects in the treatment of various types of diseases. Some studies indicate that rapeseed can be used as an anti-inflammatory, antioxidant, antiviral, hypoglycemic and anticancer agent. In the pharmaceutical industry, using rapeseed as an active ingredient may help to develop new forms drugs with wide range of therapeutic effects. This review focuses on aspects of the extraction of biocompounds from rapeseed and the study of its pharmacological properties.  相似文献   

11.
This study describes the seasonal composition and the antibacterial, antioxidant and anticholinesterase activity of the essential oil from Eugenia brasiliensis leaves. Analysis by using GC allowed the identification of 40 compounds. It was observed that the monoterpenes varied more (42%) than the sesquiterpenes (14%), and that the monoterpene hydrocarbons suffered the greatest variation throughout the year (64%). Major compounds were spathulenol in the spring (16.02 ± 0.44%) and summer (18.17 ± 0.41%), τ-cadinol in the autumn (12.83 ± 0.03%) and α-pinene (15.94 ± 0.58%) in the winter. Essential oils were tested for their antibacterial activity, and the best result was obtained from the autumn oil, with MIC = 500 μg mL? 1 against Staphylococcus saprophyticus and Pseudomonas aeruginosa. Antioxidant activity was evaluated using DPPH, lipid peroxidation and iron-reducing power assays, as well as the anticholinesterase activity. Both tests showed a weak performance of the essential oils.  相似文献   

12.
香粉叶挥发性成分提取和分析   总被引:1,自引:1,他引:0  
采用水蒸汽蒸馏法提取香粉叶的挥发组分,用乙醚萃取蒸馏溶液的挥发性成份,利用气相色谱-质谱联用仪分别定性定量分析了它们的化学成分。 结果表明,挥发油的提取率为0.75%(质量百分数,以下同),主要成分有:1,8-桉叶素28.94%、α-甲基香豆酮15.75%、4-松油醇5.13%、α-松油醇11.22%、2-羟基肉桂酸7.97%、愈创木醇2.87%。 水层乙醚萃取物得率为0.25%,主要成分有:2-甲基苯并呋喃8.47%、2H-1-苯并吡喃-2-酮24.13%、2H-1-苯并吡喃-3-醇-3,4-二氢乙酸酯18.07%、p-羟甲苯基缩水甘油醚2.09%、1-苯基苯乙基-3,3-二乙酯4.50%、丙三醇二乙酸酯17.19%、乙酸金合欢酯11.80%。  相似文献   

13.
Summary 1. The new flavonoid glycoside pasternoside has the structure of isorhamnetin 3--D-glucopyranoside 4--L-rhamnopyranoside.2. The enzymatic hydrolysis of pasternoside has given the monoglycoside deglucopasternoside, which has been shown to be isorhamnetin 4--L-rhamnopyranoside.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 1, pp. 20–26, 1966  相似文献   

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15.
A rapid, precise and low cost spectrophotometric method is proposed for the determination of methyldopa and dopamine in pharmaceutical formulations. The crude extract of sweet potato root (Ipomoea batatas (L.) Lam.) was used as an enzymatic source of polyphenol oxidase (PPO; EC.1.14.18.1). This enzyme catalyses the oxidation of catecholamines to the corresponding methyldopaquinone and dopaminequinone. Those compounds are converted by a rapid spontaneous auto-oxidation to methyldopachrome and dopaminechrome which have a strong absorption at 480 or 470 nm, respectively. The calibration graphs are linear from 2.0x10(-4) to 6.0x10(-3) M. The results obtained by the proposed enzymatic method are in close agreement with those obtained using a Pharmacopoeia procedure and also with the label values. The detection limit (three times the signal blank/slope) was 3.4x10(-5) and 3.0x10(-5) M for methyldopa and dopamine, respectively, the recovery of methyldopa and dopamine from three samples ranged from 97.5 to 102.9% of the added amount.  相似文献   

16.
The first supercritical fluid chromatography method for the determination of five major coumarins (dihydrosamidin, visnadin, samidin, khellin, and visnagin) in Ammi visnaga fruits is described. Their baseline separation was possible in less than 5 min by using a UPC2 HSS C18 SB column with 1.8 μm particle size and a mobile phase comprising CO2, methanol, acetonitrile, and diethylamine. The type of stationary phase used was of particular relevance because, except for the selected one, the others did not resolve the two structural isomers dihydrosamidin and visnadin. Method validation confirmed that the procedure is linear (R2 ≥ 0.9996) in a concentration range from 6 to 480 μg/mL, it is accurate (recovery rates: 97.2–103.6%) and precise (intraday deviation ≤ 6.6%, intraday deviation ≤ 1.7%); injecting 1 μL of standard solution, the determined limit of detection was below 1.9 μg/mL for all compounds. The analysis of different A. visnaga samples revealed their similar compositions, and khellin (0.75–1.01%) and visnagin (0.18–0.46%) were the dominant coumarins. Visnadin and dihydrosamidin, the individual quantification of which is described for the first time, were present at concentrations below 0.14%.  相似文献   

17.
Summary Qualitative and quantitative analyses of carbohydrates in olive (Olea europaea L.) tissues have been carried out by HPLC-RI. Sample purification was by two successive solid-liquid extractions to remove completely plant phenolics and pigments. Five carbohydrate peaks; sucrose (stachyose + raffinose + sucrose), glucose, galactose, fructose (fructose + myo-inositol) and mannitol were detected when plant extracts were run on a Sugar SC 1011 column operating at 75°C, using water as eluent 0.5 ml min−1. The use of two serial Sugar SC 1011 columns operating at 90°C and eluting the plant extracts with H2O−CH3CN (95/5 v/v) enables identification and quantification of nine carbohydrates, including tetra and tri-saccharides.  相似文献   

18.
In this study, the agronomical and chemical characterisation of 13 Sicilian biotypes of Thymbra capitata (L.) Cav., grown under the same agricultural and environmental condition, are reported. The main morpho-productive parameters and quali-quantitative profile of essential oils (EOs) were determined. The EOs were analysed by gas chromatography-flame ionisation detector and gas chromatography–mass spectrometry. Hierarchical cluster analysis and principal component analysis statistical methods were used to group biotypes according to the EOs chemical composition. The EO yield ranged between 4.6 and 8.1 (v/w). A total of 38 EO compounds have been identified. The compounds mostly represented were α-pinene, myrcene, α-terpinene, p-cymene, γ-terpinene, borneol, carvacrol and β-caryophyllene. In all biotypes, the carvacrol (67.4–79.5%) was the main compound, confirming that T. capitata is a carvacrol chemotype. The results showed that all Sicilian Thymbra biotypes have a good adaptation to the climatic conditions of the test environment.  相似文献   

19.
The two studied Calamintha species showed different polyphenolic content and sterol composition. Calamintha grandiflora possessed twice the polyphenolic content of Calamintha nepeta subsp. glandulosa, while the latter contained a higher number of sterols. Among them, stigmast-5-en-3β-ol was found to be the major constituent. The methanolic extract of C. grandiflora was more potent than the C. nepeta subsp. glandulosa methanolic extract in a DPPH assay, while the activity of the C. grandiflora EtOAc fraction was weaker than its C. nepeta subsp. glandulosa counterpart. Fractions of C. nepeta subsp. glandulosa showed higher activity using a β-carotene bleaching test. The petrol ether fraction of C. grandiflora showed significant inhibition of NO production.  相似文献   

20.
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