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1.
为了奠定频繁开花型高产小桐子的快繁及转基因基础,通过对小桐子茎段腋芽培养、叶片和叶柄愈伤诱导及不定芽分化的不同激素组合培养进行研究。结果表明:适合该高产品种的茎段培养的最佳培养基为MS+6-BA 0.5 mg/L+IBA 0.1 mg/L,叶片愈伤诱导及不定芽分化培养基为MS+6-BA 2.5 mg/L+IBA 0.5 mg/L,叶柄愈伤诱导及不定芽分化培养基为MS+6-BA 1.0 mg/L+IBA 0.2 mg/L,生根培养以1/2MS+IBA 0.5 mg/L+AC 0.1%较为适宜。引起小桐子组培苗玻璃化现象的主要原因之一是BA浓度过高;在不定芽的分化培养中,愈伤过多会严重影响不定芽的数量及质量。  相似文献   

2.
麻疯树生物学研究进展及其开发利用   总被引:1,自引:0,他引:1  
麻疯树是重要的可再生生物能源植物之一。本文概述了麻疯树的植物学特点、分布、繁殖方法、遗传改良研究及其开发利用前景。  相似文献   

3.
The objective of this study was to optimize the mechanical oil extraction of Jatropha curcas seeds by increasing the efficiency of oil recovery and decreasing oil residues in press cake. The experiments were carried out with mechanical screw press type - Komet D85-1G. Four setups were created by parameter combination of two different screws (16 and 21.5 mm choke ring size), with two different press cylinders (1 and 1.5 mm bore size), three different nozzles (8, 10 and 12 mm nozzle diameter) and three rotational speeds (low, medium and high). Oil recovery reduced when rotational speed increases for all setups; highest oil was 89.4% (m/m). The oil recovery was increasing when energy input increased and decreasing when seed material throughput increased. The relations between energy input and seed material throughput followed a strict pattern, which correlated with oil recovery. This correlation can be used for determining the optimal operation parameters.  相似文献   

4.
The essential oils obtained by hydrodistillation from the aerial parts of Tunisian native Hypericum perfoliatum L. (sect. Drosocarpium Spach.) and Hypericum tomentosum (sect. Adenosepalum Spach.) were analyzed by GC and GC–MS. Thirty-two compounds were identified in the essential oils of H. perfoliatum with α-pinene (13.1%), allo-aromadendrene (11.4%), germacrene-D (10.6%), n-octane (7.3%), α-selinene (6.5%) and β-selinene (5.5%) as main constituents. Sixty-seven components were identified in the oil of H. tomentosum with menthone (17.0%), n-octane (9.9%), β-caryophyllene (5.3%), α-pinene (5.2%), lauric acid (4.1%) and β-pinene (3.7%) as the most abundant components. Both oils were characterized by the presence of many components which could have numerous applications in food, pharmaceutical and perfume industries.  相似文献   

5.
The chemical composition, main physicochemical properties and thermal stability of oil extracted from Acacia senegal seeds were evaluated. The oil, moisture and the ash contents of the seeds were 9.80%, 6.92% and 3.82%, respectively. Physicochemical properties of the oil were iodine value, 106.56 g/100 g of oil; saponification value, 190.23 mg KOH/g of oil; refractive index (25 °C), 1.471; unsaponifiable matter, 0.93%; acidity, 6.41% and peroxide value, 5.43 meq. O2/kg of oil. The main fatty acids in the oil were oleic acid (43.62%) followed by linoleic acid (30.66%) and palmitic acid (11.04%). The triacylglycerols (TAGs) with equivalent carbon number ECN 44 (34.90%) were dominant, followed by TAGs ECN 46 (28.19%), TAGs ECN 42 (16.48%) and TAGs ECN 48 (11.23%). The thermal stability analysed in a normal oxidizing atmosphere showed that the oil decomposition began at 268.6 °C and ended at 618.5 °C, with two stages of decomposition at 401.5 °C and 576.3 °C. According to these results, A. senegal seed oil has physicochemical properties, fatty acids composition and thermal characteristics that may become interesting for specific applications in several segments of food and non-food industries.  相似文献   

6.
The utilization of Hura crepitans seed oil in the formulation of alkyd resins was investigated using a two-stage alcoholysis-polyesterification method. The percentage yield of the oil was 36.4%; and the physicochemical characterization revealed that the seed oil is an unsaturated semi-drying oil. The fatty acid profile of the oil showed that it contains linoleic acid (81.6%) as the most abundant fatty acid, and two other fatty acids: palmitic acid (16.92%) and stearic acid (1.76%). Short (I), medium (II) and long (III) oil alkyds were synthesized using the oil, glycerol and phthalic anhydride in different ratios. Properties of the three prepared samples of H. crepitans seed oil alkyds having oil content of 30% (I), 50% (II), and 65% (III) were evaluated. The alkyd resins synthesized compared favourably with the commercially available alkyd resin. The presence of unsaturation in the oil was confirmed by infra-red peak at 2930 cm−1 attributed to CC stretch. The infra-red peaks of the sample also compared well with that of the commercial sample indicating that H. crepitans seed oil has been successfully converted to alkyd resin. Evaluation of prepared alkyds by determination of acid values, solubility in butanol and toluene, resistance of dry film to acid, alkali and water, and drying time revealed that H. crepitans seed oil is a potential raw material for the coating industry.  相似文献   

7.
As a novel renewable resource, Sapindus mukorossi seed oil (SMSO) with an iodine value of 84.86 g/100 g, and containing 51.0 ± 0.9% oleic acid (18:1), 6.6 ± 0.6% linoleic acid (18:2), 1.1 ± 0.3% linolenic acid (18:3), and 23.1 ± 0.9% eicosanoic acid (20:1), was epoxidized using hydrogen peroxide as oxygen donor and stearic acid as active oxygen carrier in the presence of immobilized Candida antarctica lipase B. The effect of the amount of stearic acid on the enzymatic epoxidation was investigated. Response surface methodology (RSM) was used to study and optimize the effects of variables (reaction temperature, enzyme load, mole ratio of H2O2/CC-bonds, and reaction time) on the epoxy oxygen group content (EOC) of epoxidized SMSO. Results showed that stearic acid as active oxygen carrier could enhance the enzymatic epoxidation of SMSO. The variables of reaction temperature and enzyme load were the most significant in the process. A two second-order model was satisfactorily fitted the data (R2 = 0.9723) with non-significant lack of fit. The optimum EOC of epoxidized SMSO was 4.6 ± 0.3% under the conditions of 50.0 °C, 7.0 h, 2.00% (relative to the weight of SMSO) enzyme load, and 4:1 mole ratio of H2O2/CC-bonds.  相似文献   

8.
Preliminary chemical studies were undertaken during one year on plant materials collected in a 40 ha field located in Henderson, Province of Buenos Aires, in order to determine the technical viability of the industrial production of essential oil from bay leaves (Laurus nobilis L., Lauraceae) growing in Argentina. The oils were extracted at a pilot scale plant and analyzed by GC–FID-MS. The apparent density of the plant material used for the distillation ranged from 90 g L−1 to 170 g L−1, depending on the type of material. The quality of the volatile oils obtained complied with market requirements and were in agreement with values reported from other countries. No considerable variations were observed in the chemical composition of the oils throughout the year. Taking in account the composition of the sub-fractions obtained during the distillation process, the quality of the final essential oil can be adjusted by fractional distillation. The occurrence of alcohol terpenes and phenols in the condensed waters (hydrolate) makes them a possible alternative to be used in industry. Moreover, and due to the good energetic and digestibility values obtained, our results showed that the exhausted plant material obtained after distillation could be a putative fibrous feed for ruminants. Both, hydrolate and exhausted plant materials are resources that can enhance added values in new endeavours. This is the first report on bay leaves essential oil production at industrial scale in Argentina.  相似文献   

9.
在考察提取溶剂、提取方法对总黄酮提取率的影响的基础上,运用正交试验对艾纳香中总黄酮的提取条件进行优化,确定最佳提取工艺.结果表明,艾纳香总黄酮最佳提取工艺为:30%的乙醇以1∶300料液比投料,以85 Hz的频率超声提取2次,每次30 min.在该最佳提取工艺下,艾纳香总黄酮提取量为208.6 mg/g.  相似文献   

10.
Supercritical carbon dioxide (SC-CO2) was employed to extract oil from hemp (Cannabis sativa L.) seeds. For ground seeds, the supercritical extraction was carried out at temperatures of 40, 60 and 80 °C and pressures of 300 and 400 bar. Different solvent-ratios were applied. Supercritical CO2 extractions were compared with a conventional technique, n-hexane in Soxhlet. The extraction yields, fatty acid composition of the oil and oxidation stability were determined. The seed samples used in this work contained 81% PUFAs, of which 59.6% was linoleic acid (ω-6), 3.4% γ-linolenic (ω-3), and 18% α-linolenic (ω-6). The highest oil yield from seeds was 22%, corresponding to 72% recovery, at 300 bar and 40 °C and at 400 bar and 80 °C. The highest oxidation stability corresponding to 2.16 mM Eq Vit E was obtained at 300 bar and 80 °C.  相似文献   

11.
Hydrodistilled volatile oil obtained from the aerial parts of Artemisia annua L., cultivated near Sarajevo, Bosnia, was analyzed by GC-MS. More than one hundred compounds were identi?ed, representing 95.5% of the total oil. The major constituents of essential oil were oxygenated monoterpenes, artemisia ketone (30.7%) and camphor (15.8%). Isolated essential oil was tested for radical-scavenging ability using the stable DPPH radical, the ABTS radical, for reducing power ability with a test based on the reduction of ferric cations, for reducing ability of hydroxy radical in ORAC assay, and for metal chelating ability using the ferrozine assay. In all tests oil did not show a prominent antioxidant activity, but still comparable with thymol, an already known antioxidant. The screening of antimicrobial activity of oil was individually evaluated against representatives of Gram-positive, Gram-negative bacteria and fungi, using the agar diffusion method. All tested microorganisms were inhibited by essential oil. To the best of our knowledge, this is the first report of antimicrobial activity of essential oil of A. annua against Haemophilus influenzae, Enterococcus faecalis, Streptococcus pneumoniae, Micrococcus luteus and Candida krusei microbial strains. The antioxidant, antibacterial and antifungal activity of essential oil of A. annua from Bosnia is presented here for the first time and extends our knowledge in the range of valuable biological activities and possible roles in therapy associated with this medicinal herb.  相似文献   

12.
Baccharis (Compositae-Asteraceae) is a large genus of plants distributed from the USA to Argentina, of which 90% are located in South America. In recent decades, species of the genus have been studied, due to their importance as sources of novel active components with possible applications in the pharmaceutical and chemical industries. This work studied three species of Baccharis: Baccharis uncinella DC, Baccharis anomala DC and Baccharis dentata (Vell) G.M. Barroso collected in São Francisco de Paula in southern Brazil. The aim of this work is the evaluation of the aromatic potential of the essential oil obtained by steam distillation method and the simulation of the extraction data by means of a mathematical model. A mathematical model based on mass transfer fundamentals is developed and applied to correlate the experimental data. This model is based on the existence of the broken and intact cells, in which the oil located in the broken cells is rapidly extracted and the oil from intact cells diffuses slowly to the surface of the vegetal material. The analysis of the essential oil was carried through by GC-MS and the major compounds identified to both processes were α-pinene, β-pinene, and spathulenol (B. uncinella), spathulenol, β-caryophyllene, and β-selinene (B. anomala), and germacrene-D, caryophyllene oxide, and spathulenol (B. dentata).  相似文献   

13.
以海南产姜黄为材料,研究不同采收期姜黄精油含量的变化,并采用气相色谱-质谱联用技术(GCMS)对精油化学成分进行分析。结果表明:在根茎膨大期(10-17)姜黄精油的含量最高,达到80 mL/kg,此后姜黄精油的含量有所减少,至姜黄枯萎期时(03-04)精油含量为67 mL/kg;不同采收期姜黄精油的化学成分基本相同,但相对含量存在差异;4个采收期姜黄精油分别鉴定出36、36、34和34种化学成分,其中主要化学成分为芳姜黄酮、α-姜黄酮、姜醇、β-红没药烯、2-表-α-雪松烯、芳姜黄烯等倍半萜类化合物,且尤以芳姜黄酮在不同时期姜黄精油中含量最高,分别占总量的49.259%、33.794%、33.610%和44.829%。  相似文献   

14.
The chemical composition of essential oils isolated from aerial parts of native populations of Origanum vulgare L. from northwestern Himalaya was investigated by enantioselective gas chromatography (enantio-GC), capillary-gas chromatography (capillary-GC) and GC–MS. Seventy compounds, which accounted for 84.9–97% of the oil composition, have been identified. The oils were allotted to two main groups; the first group had a high percentage of components belonging to the thymol/carvacrol biosynthetic pathway and the second was characterized by a different sesquiterpene composition and a high linalool and bornyl acetate percentage. Essential oils of O. vulgare populations from Rilkot and Dhanachuli areas in northwestern Himalaya were characterized by high monoterpenoids proportions as compared to Nainital and Bhowali populations, which were dominated by sesquiterpenoids. High proportions of thymol (29.2–82%) were found only in two populations. Composition of the samples collected from Dhanachuli area differed from Nainital and Bhowali collections by a unique presence of carvacrol. Notably, there were significant differences in the concentration of rest of the terpenes in all the collections. On enantio-GC, enantiomeric excess for (3R) (−)- and (3S) (+)-linalool, (S) (+)- and (R) (−)-terpinen-4-ol, (S) (−)- and (R) (+)-α-terpineol, (1S) (−)-bornyl acetate and (1S) (−)-borneol were established in populations from Bhowali and Dhanachuli area. Moreover, linalool type oregano may be useful in promoting wider commercial utilization of the biodiversity of this species.  相似文献   

15.
周辉 《热带作物学报》2013,34(12):2489-2494
以提高余甘果肉中的多酚提取率为目的,采用超声波辅助乙醇提取。以乙醇浓度80%为固定条件,通过4组单因素试验探讨了超声波提取温度、功率、提取时间及料液比对余甘多酚提取效果的影响;运用Box-Behnken设计,通过3因素3水平的响应面分析法优化了超声波辅助乙醇提取余甘多酚的工艺。结果表明:在乙醇浓度80%,料液比1 g ∶ 25 mL条件下,余甘多酚的最佳超声波辅助乙醇提取的工艺条件为超声波提取温度43.80 ℃,功率250.96 W,提取时间23.90 min。按此工艺条件提取的余甘多酚提取率为17.21%。  相似文献   

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