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1.
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   

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Pachyrhizus erosus seeds were analysed for proximate composition, minerals, protein fractions, antinutritional factors, and rotenoids. The seeds showed a high content of proteins, lipids, Fe and Ca, in comparison to other legumes. Glutelins constitute the highest protein fraction, followed by globulins. Antinutritional substances detected as tannins, hemagglutinating activity and trypsin inhibitory activity, were in low concentrations. Seeds were also processed to obtain a flour which showed proper characteristics, good in vitro digestibility, significant rotenoid reduction level and amino acid composition rich in essential amino acids, except methionine.  相似文献   

4.
There is a growing interest of industry to replace synthetic chemicals by natural products with bioactive properties from plant origin. The aim of this study was to determine the chemical composition of European pennyroyal (Mentha pulegium) essential oil and to characterize the in vitro antioxidant and antimicrobial activities of its water (hot and cold) and ethanolic extracts and of the essential oil. The essential oil revealed menthone, pulegone and neo-menthol as the main constituents, comprising 35.9, 23.2 and 9.2% of the essential oil, respectively. The hot water extract exhibited the highest antioxidant activity and phenol content. In contrast, the extracts were not very effective to inhibit the growth of the seven foodborne spoilage and pathogenic bacteria tested, but the essential oil showed antibacterial activity against all bacterial strains. In conclusion, extracts and essential oil of M. pulegium from Mediterranean origin have huge potential as an alternative to chemical additives for the food industry.  相似文献   

5.
The essential oils of aerial parts of three Artemisia species (A. absinthium, A. santonicum and A. spicigera) were isolated by hydrodistillation method and tested for their toxicity against to granary weevil, Sitophilus granarius (L.) (Coleoptera: Curculionidae). All of the essential oils tested were found to be toxic to adults of S. granarius. The oils showed about 80–90% mortality of granary weevil, S. granarius at a dose of 9 μl/l air after 48 h of exposure. The constituents of these oils isolated from Artemisia spp. were also analyzed by GC–MS method. Camphor, 1,8-cineole, chamazulene, nuciferol propionate, nuciferol butanoate, caryophyllene oxide, terpinen-4-ol, borneol and α-terpineol were the predominant components of the oils. Some pure compounds (camphor, 1,8-cineole, terpinen-4-ol, borneol, bornyl acetate and α-terpineol) identified as major component in the oils, at 0.5, 0.75 and 1 μl/l air doses were also tested for their toxicity against S. granarius. While all pure compounds were found to be toxic against S. granarius, 1,8-cineole and terpinen-4-ol were more toxic among the tested pure compounds. 1,8-Cineole and terpinen-4-ol showed 100% mortality at all doses after 12 h of exposure. It can be concluded that essential oils of three Artemisia species and their major components, 1,8-cineole and terpinen-4-ol are potential control agents against S. granarius.  相似文献   

6.
In this work, two Helichrysum italicum (Roth) G. Don ssp. microphyllum (Willd.) Nym. genotypes (genotype 1 and genotype 12) collected from different areas of Corsica were used. After the taxonomic identification based on several specific morphological characters, the two genotypes were subjected to microscopic studies. The precise structure of the glandular trichomes, secreting essential oils, on the flower heads and leaves of H. italicum (Roth) G. Don ssp. microphyllum (Willd.) Nym. are described here for the first time. Volatile constituents from both field-grown genotypes 1 and 12 were analyzed and their composition compared: monoterpenes were the most abundant class of compounds with nerol and its esters as the main metabolites. Genotype 12 was used to establish an efficient micropropagation protocol. For proliferation, different concentrations of 6-benzylaminopurine (BAP) alone or in combination with indole-3-butyric acid (IBA) were tested adding sucrose (20% or 30%). To define the optimal conditions for in vitro rooting, the shoots obtained were divided and transferred to the culture medium without growth regulators or enriched by different auxins in combination with sucrose (20% or 30%). Acclimatization, carried out in different conditions was easy, registering high survival percentages. The results achieved in this study allowed to obtain selected and standardized plants suitable for the exploitation in industrial sectors of this interesting species.  相似文献   

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大豆种子发育过程中差异表达蛋白的蛋白质组分析   总被引:1,自引:0,他引:1  
采用蛋白质组学技术研究了大豆N2899种子发育过程中蛋白质的差异表达。运用PDQuest软件比较分析不同发育时期(15,20,30,40,50 DAF和成熟种子)大豆种子蛋白的双向电泳图谱,在考染的2-D胶上共检测到337个蛋白点。有些蛋白质在整个发育过程中都出现,而另外一些只出现在发育早期或成熟的种子中。利用基质辅助-激光解吸/电离-飞行时间-质谱(MALDI-TOF-MS)技术,分析了不同发育时期30个差异表达蛋白,并用Pro-found(http://www.prowl.rockefeller.edu)工具,对质谱产生的肽质量指纹(PMF)数据进行NCBInr数据库检索,结果鉴定了18个蛋白质。比较发现,这些蛋白主要参与种子的成熟(如伴豆球蛋白)、逆境胁迫反应(如抗坏血酸过氧化酶)、细胞分裂(如Skp1)和蛋白运输(如钙网蛋白)等。研究表明,种子发育过程十分复杂,所鉴定的蛋白质,可为从分子水平上研究大豆种子发育进程中蛋白的积累和调控奠定基础。  相似文献   

9.
Natural essential oils extracted from aromatic crops through steam distillation are extensively used in fragrance, flavour and pharmaceutical industries and in aromatherapy. During steam distillation, a part of the essential oil becomes dissolved in condensate or distillation water and is lost as this water is discarded. A method was developed to recover the dissolved essential oil from condensate water. Palmarosa (Cymbopogon martinii (Roxb.) Wats. var. motia Burk., family: Poaceae), an important aromatic grass was used as the test crop. The distillation water of palmarosa mixed with hexane in 10:1 proportion was thoroughly shaken for 30 min to trap the dissolved essential oil. Hexane was then distilled to yield ‘secondary’ or ‘recovered’ oil. In palmarosa, the ‘primary’ or ‘decanted’ oil (obtained directly by distilling the crop biomass) accounted for 92% and the recovered oil accounted for 8% of the total oil yield. The solvent loss in this process was 4–7%. Experiments conducted in the laboratory with the essential oil showed that the water solubility of palmarosa oil ranged from 0.12 to 0.15% at 31 °C and 0.15 to 0.20% at 80 °C. Hexane recovered up to 97% of the dissolved essential oil in water. The recovered essential oil was richer in organoleptically important oxygenated compounds linalool (2.6–3.8%), geraniol (91.8–92.8%) and geranial (1.8–2.0%) compared to the primary oil.  相似文献   

10.
Seasonal chemical composition, in sacco organic matter (OM) and crude protein (CP) degradabilities and CP fractions of haulms of three improved (ITA2, ITA6 and ITA8) and three commercial (Oloyin, Peu and Sokoto) cowpea varieties harvested in wet and dry seasons were evaluated in a 2 × 2 factorial arrangement of treatments. Effective degradation of OM and CP was estimated at assumed outflow rates of 2 and 4% h?1. Commercial haulms (all the other parts of the cowpea minus the grains) had greater (P < 0·001) CP than improved varieties, whereas neutral detergent fibre and acid detergent fibre were greater (P < 0·001) in improved vs. commercial haulms. Interactions between variety group (improved vs. commercial) and season were observed for CP (P = 0·002), lignin (P = 0·003) and hemicellulose (P = 0·030) contents of the haulms. Similarly, a group × season interaction was observed for effective degradation of OM at an outflow rate of 2%. The proportion of substrate degraded in the samples harvested in the wet season was generally less (P < 0·001) than in the dry season. Effective degradability values of OM at the assumed passage rates were greater (P < 0·001) for improved vs. commercial cowpea haulms. Interactions between group and season were observed for all but one of the CP fractions. Seasonal differences in the quality of haulms showed that attention must be given to handling of haulms to minimize the amount of leaves lost during the wet season.  相似文献   

11.
Einkorn (Triticum monococcum L. subsp. monococcum) is an ancient wheat appreciated for its high proteins, carotenoids and tocols content. To better understand its potential for human consumption and food preparation, composition and pasting properties of 65 einkorn accessions, of different geographical origin but cultivated at S. Angelo Lodigiano (Italy), were evaluated. Eight Triticum turgidum and seven Triticum aestivum cultivars, belonging to different subspecies, were assessed as controls.On average, the einkorn samples had light seeds (25.0 mg/kernel), extra-soft texture (238.3 g), high protein content (18.2%), high ash content (2.35%), low SDS sedimentation volume (25.6 ml), high carotenoids (8.36 μg/g) and high yellow pigments (8.46 μg/g). The pasting parameters studied were peak viscosity (average: 2426 cP), breakdown (765 cP), final viscosity (2788 cP) and setback (1126 cP). Total amylose (25.7%) and total starch (65.5%) were also measured. Significant differences from the controls and a broad variation for all the traits analysed were observed. Einkorns from diverse geographical areas showed different mean values for all characters, apart from ash content.The good pasting properties, coupled with high proteins and carotenoids content, suggest that einkorn is particularly suited for the production of baby and specialty foods.  相似文献   

12.
茶树中提纯总RNA的研究   总被引:23,自引:4,他引:19  
在克氏一步法分离总RNA的基础上 ,根据茶树叶片生化成分特点 ,做了部分修改 ,并研究了不同浓度的L -半胱氨酸和可溶性聚乙烯吡咯烷酮 (PVP)、不溶性PVP对提取的RNA纯度、回收率和完整性的影响。分光光度计检测和变性琼脂糖凝胶电泳结果证明 :使用本方法并加入 5- 10mmol LL -半胱氨酸或 4 % - 6 %可溶性PVP能提高RNA纯度和 (或 )回收率 ,研磨时加入5% - 10 %不溶性PVP对提高RNA完整性有较好的效果  相似文献   

13.
甜菜碱是一种能在逆境下大量积累的无毒性渗透相溶物质,而甜菜碱醛脱氢酶(BADH)是甜菜碱合成途径中的关键酶之一。本实验采用SMART-RACE技术获得了茶树甜菜碱醛脱氢酶基因的全长cDNA序列,命名为CsBADH1(GenBank登陆号:JX050145),并对其进行相关的生物信息学分析。结果表明:CsBADH1的cDNA序列全长1 972 bp,其开放阅读框(ORF)为1 518 bp,编码505个氨基酸,预测分子量为54.8 kD,理论等电点(PI)为5.652,是疏水性很强的蛋白,且具有BADH基因典型的高度保守十肽基序(VTLELGGKSP)和与醛脱氢酶(ALDHs)功能有关的半胱氨酸残基(C)。系统进化树分析表明,茶树BADH氨基酸序列与人参(Panax ginseng)的亲缘关系最近,相似度达87%,其余相似性也大部分在80%以上。实时荧光定量PCR分析结果显示:该基因在经历一定时间的冷驯化后表达量升高,说明CsBADH1基因可能参与茶树的冷驯化作用。  相似文献   

14.
考察了无刺卡因、巴厘和珍珠3个菠萝品种吸芽苗冠芽的变异情况,结果显示:无刺卡因冠芽全为单冠芽,巴厘和珍珠则存在冠芽变异,其中珍珠发生冠芽变异显著高于无刺卡因和巴厘,主要是因为珍珠的复冠率显著高于无刺卡因和巴厘,但3个品种鸡冠状冠芽发生率的差异未达到显著.利用从巴厘和珍珠中发现的3株鸡冠状冠芽及其母株再次繁育成苗,所有鸡冠状冠芽苗成熟时均未再现鸡冠状冠芽表型,表明鸡冠状冠芽不能稳定遗传,受环境影响.然而珍珠鸡冠状冠芽母株的吸芽苗却又再现复冠和鸡冠状冠芽.再次表明品种珍珠的吸芽易于产生冠芽变异.  相似文献   

15.
茶树抗逆相关基因ERF的克隆与表达特性分析   总被引:1,自引:2,他引:1  
对利用cDNA-AFLP技术所获得的茶树低温诱导差异表达片段TDF,通过RACE方法获得含完整编码区序列的茶树ERF基因cDNA克隆,其开放阅读框编码212个氨基酸,包含一个保守的结构域AP2/ERF,与多种植物ERF蛋白具有高度同源性。qRT-PCR分析表明,茶树ERF基因受低温、乙烯、脱水、NaCl等上调表达,最大表达量分别是诱导前的121.1、22.6、2.6和2.2倍。在不同组织器官中,茶树ERF基因在转录水平上存在显著差异,成熟叶片中表达最高,其次是芽,而根和茎中表达量较低且相当,花和种子中表达极低。推测该基因在茶树响应非生物胁迫中发挥重要作用以及在组织中的表达受到严格控制。  相似文献   

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The chemical, sensory and rheological properties of porridges made from blends of sprouted sorghum, bambara groundnuts and fermented sweet potatoes were examined. Sorghum and bambara groundnuts were sprouted for 48 h while sweet potatoes were fermented for the same period. Blends were formulated from the processed ingredients in the ratio of 60:40:0, 57:42:1, 55:44:1 and 52:46:2 (protein basis) of sorghum, bambara groundnuts and sweet potatoes. Porridges were prepared from the composite flours and the traditional sorghum complementary food. Standard assay methods were used to evaluate the flours for nutrient composition. The porridges were also tested for sensory properties and viscosity. Processing increased the levels of most of the nutrients evaluated. Relative to the sorghum traditional complementary food, thecomposite flours had higher levels of lipids, protein, ash, crude fiber and minerals (p<0.05). The porridges from the composite flours were generally liked slightly by the panelists and were about seven times less viscous than the porridge from the traditional sorghum complementary food. Use of the composite flours, particularly the 52:46:2 blend, as a traditional complementary food should be encouraged in Nigeria especially with the increasing cost of commercial complementary foods.  相似文献   

18.
Proximate composition, extraction, characterization and comparative assessment of Cocos nucifera and Colocynthis citrullus seeds and seed oils were evaluated in this work using standard analytical techniques. The results showed the percentage (%) moisture, crude fibre, ash, crude protein, lipids and total carbohydrate contents of the seeds as 7.51 and 4.27, 7.70 and 5.51, 1.02 and 2.94, 10.57 and 11.67, 47.80 and 50.42 and 32.84 and 29.47 while the calorific values were 553.99 and 567.32 Kcal/100 g for C. nucifera and C. citrullus, respectively. The two seed oils were odourless and at room temperature (30 degrees C) liquids, with a pale yellow to yellowish colouration. Lipid indices of the seed oils indicated the Acid Values (AV) as 2.06-6.36 mg NaOH g(-1) and 2.99-6.17 mg NaOH g(-1), Free Fatty Acids (FFA) as 1.03-3.18 and 1.49-3.09%, Saponification Values (SV) as 252.44-257.59 and 196.82-201.03 mg KOH g(-1), Iodine Values (IV) as 9.73-10.99 and 110.93-111.46 mg of I2 g(-1) of oil and Peroxide Values (PV) as 0.21-0.21 and 1.53-2.72 mg O2 kg(-1) for soxhlet-mechanical extracted C. nucifera and C. citrullus seed oils, respectively. The studied characteristics of the oil extracts in most cases compared favourably with most conventional vegetable oils sold in the Nigeria markets; however, there were some observed levels of significant differences in the values at p < or = 0.05. These results suggest that the seeds examined may be nutritionally potent and also viable sources of seed oils judging by their oil yield. The data also showed that the seed oils were edible inferring from their low AV and their corresponding low FFA contents. Industrially, the results revealed the seed oils to have great potentials in soap manufacturing industries because of their high SV. They were also shown to be non-drying due to their low IV which also suggested that the oils contain few unsaturated bonds and therefore have low susceptibility to oxidative rancidity and deterioration as confirmed by their low PV which also serves as indicators of the presence or high levels of anti-oxidants in the oils.  相似文献   

19.
不同品种茶树氮素效率差异研究   总被引:14,自引:1,他引:14  
比较了6个茶树品种的氮素效率差异。结果表明,在4种施氮条件下,生物量增加值、新梢生长量、氮素吸收效率、氮素生理利用效率、氮素经济效率和总的氮素效率存在着显著的品种间差异。氮素效率的两个子性状—吸收效率和生理利用效率对其贡献大小不同,吸收效率是决定不同品种茶树氮素效率差异的主要因素。  相似文献   

20.
Seeds of Teramnus labialis (L.) Spreng.(Fabaceae), used as food by Malayali tribals in theKollihills of Salem District, Tamil Nadu in SouthIndia, were investigated for their nutritional value. These seeds were analyzed for proximate composition,total (true) seed proteins, seed proteinfractions, amino acid composition, fatty acidcomposition, minerals and antinutritional factors. Crude protein, crude fat, ash, and nitrogen freeextracts constituted 22.86%, 6.10%, 4.62%, and,58.15%, respectively, of the seed weight. The caloricvalue of 100 g dry matter of seed material was 378.94kcal. The essential amino acids lysine, leucine +isoleucine, arginine, valine and histidine werepresent in relatively large quantities. Theunsaturated fatty acids constituted more than 60% ofthe crude fat. Concentrations of minerals such aspotassium, magnesium, calcium, and, phosphorus werehigh. Antinutritional factors such as total freephenols, tannins, L-DOPA, hydrogen cyanide andphytic acid were present in minute quantities. Theseantinutritional factors are potentially eliminated using the conventional method of soaking the seeds in water,boiling with water and decanting prior to consumption.  相似文献   

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