超声波辅助法提取金莲花中黄酮工艺研究

以超声波辅助法对大兴安岭金莲花中总黄酮的最佳提取工艺条件进行研究。以温度、料液比、乙醇体积分数、超声时间为提取影响因素,通过正交试验优化提取工艺。结果表明,各因素对总黄酮提取的影响次序为:料液比>超声时间>温度>乙醇体积分数,超声波辅助法的最佳工艺提取条件为:提取温度为50℃,料液比1:55,乙醇体积分数75%,超声时间40 min,总黄酮的提取率达4.659%。     

蜂胶中黄酮类化合物提取工艺的优化

蜂胶具有消炎、杀菌及抗氧化等生理活性。通过对蜂胶有效成分黄酮提取工艺的研究表明,影响蜂胶总黄酮提取率的主要因素是提取温度、提取时间、乙醇体积分数和料液比对提取率影响甚微。水浴条件下蜂胶总黄酮的最佳提取工艺是:提取温度60℃,提取时间3h,乙醇体积分数为80%,料液比1∶25,此条件下测得黄酮得率为43.50%。     

响应面法优化回流提取苦荞麦黄酮工艺研究

为优化苦荞麦黄酮的回流提取工艺,采用单因素和响应面试验研究回流法,研究乙醇体积分数、液料比、提取温度、提取时间对苦荞麦中黄酮提取效果的影响。研究表明,最佳提取工艺条件为液料比6 mL/g,提取时间30 min,提取温度40℃,乙醇体积分数56%。在此条件下,苦荞麦中黄酮得率为3.378 mg/g,验证值为3.434 mg/g,误差为1.66%。     

超声微波协同萃取红豆中总黄酮的工艺研究

确定超声微波协同萃取红豆中总黄酮的最佳提取工艺,测定红豆中总黄酮的含量。研究提取时间、微波功率、提取温度、乙醇体积分数、料液比等因素对总黄酮提取率的影响。在进行单因素试验之后,通过正交试验优化超声微波协同萃取红豆总黄酮类化合物的工艺条件。结果表明,对红豆中总黄酮提取的影响程度为乙醇体积分数料液比提取时间微波功率。超声微波协同法提取总黄酮的最佳工艺条件为提取时间30 min,微波功率400 W,提取温度45℃,乙醇体积分数60%,料液比1∶25;提取3次,总黄酮提取量为1.75 mg/g。     

巨峰葡萄皮中白藜芦醇提取工艺的研究

采用超声波辅助技术研究白藜芦醇的提取工艺,并进行单因素试验和正交试验,分析对料液比、乙醇体积分数、超声时间、水浴温度对巨峰葡萄皮中白藜芦醇提取率的影响,确定最佳工艺条件为料液比1∶12,乙醇体积分数60%,超声时间12 min,水浴温度30℃,此时巨峰葡萄皮中白藜芦醇提取率为0.014 9%。     

山药总皂甙的提取研究

以山药中总皂甙提取率为考察指标,应用单因素试验和正交设计对山药总皂甙提取工艺中的浸提温度、乙醇的体积分数、浸提时间、料液比进行了研究。以薯蓣皂甙为标准,香草醛—高氯酸为显色剂,冰醋酸为溶剂,用分光光度计在波长为544nm处对山药总皂甙的含量进行了测定,得出山药总皂甙的最佳提取工艺条件是:浸提温度为60℃,浸提时间为6h,乙醇体积分数为80%,料液比为1∶8。     

柚籽中类柠檬苦素的初提工艺研究

以脱脂柚籽为原料,乙醇为提取剂,以乙醇体积分数、提取温度、料液比为考查因素,提取得到的类柠檬苦素含量为指标进行了单因素试验和正交试验。结果表明,料液比对柚籽中类柠檬苦素提取率影响最大因素,然后依次为提取温度和乙醇体积分数;最佳提取工艺条件为乙醇体积分数70%,提取温度70℃,料液比1∶45。     

桑黄残渣黄酮提取工艺研究

利用桑黄提取多糖后的残渣,采用乙醇回流法提取桑黄黄酮,实现桑黄高值化。首先对提取温度、提取时间、料液比、乙醇体积分数进行单因素试验,然后通过正交试验优化提取黄酮的工艺条件,并通过与VC的对比研究桑黄黄酮粗提液对·OH和DPPH·的清除能力,以探讨其抗氧化活性。研究表明,最佳工艺条件为提取温度90℃,提取时间4 h,料液比1∶30,乙醇体积分数60%,在此条件下黄酮的提取率为5.12%,所得到的桑黄黄酮粗提液对·OH的清除能力比VC高,对DPPH·的清除能力比VC稍弱。     

桑黄残渣黄酮提取工艺研究

利用桑黄提取多糖后的残渣,采用乙醇回流法提取桑黄黄酮,实现桑黄高值化。首先对提取温度、提取时间、料液比、乙醇体积分数进行单因素试验,然后通过正交试验优化提取黄酮的工艺条件,并通过与VC的对比研究桑黄黄酮粗提液对·OH和DPPH·的清除能力,以探讨其抗氧化活性。研究表明,最佳工艺条件为提取温度90℃,提取时间4 h,料液比1∶30,乙醇体积分数60%,在此条件下黄酮的提取率为5.12%,所得到的桑黄黄酮粗提液对·OH的清除能力比VC高,对DPPH·的清除能力比VC稍弱。     

超声辅助法提取红豆种皮中花色苷的工艺研究

采用超声辅助乙醇溶剂法对红豆种皮中的花色苷进行了提取工艺研究。通过单因素试验考察了料液比、pH、乙醇体积分数、超声温度以及超声功率对红豆种皮花色苷提取效果的影响,在此基础上进行响应面试验,进一步优化了红豆种皮色素的提取工艺。结果表明：影响花色苷提取效果的各因素顺序为 pH＞超声温度＞乙醇浓度＞料液比,超声功率对提取率的影响不大。超声法提取红豆种皮花色苷的最适工艺条件为: 料液比1∶34（g/mL）,pH为3,乙醇体积分数30%,超声温度55 ℃,超声功率350 W。在上述最佳工艺条件下,红豆种皮中花色苷的提取效果最好,提取液中花色苷含量可达（82.35±3.28）mg/100 g。     

Biological Activity and Quantification of Suspected Allelochemicals from Alfalfa Plant Parts

Autotoxicity restricts reseeding of alfalfa (Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments. A series of aqueous extracts from leaves, stems, roots and seeds of alfalfa ‘Vernal’ were bioassayed against alfalfa seedlings of the same cultivar to determine their autotoxicity. The highest inhibition was found in the extracts from the leaves. Extracts at 40 g dry tissue l^?1 from alfalfa leaves were 15.4, 17.5 and 28.7 times more toxic to alfalfa root growth than were those from roots, stems and seeds, respectively. A high‐performance liquid chromatography (HPLC) analysis with nine standard compounds showed that the concentrations and compositions of allelopathic compounds depended on the plant parts. In leaf extracts that showed the most inhibitory effect on root growth, the highest amounts of allelochemicals were detected. Among nine phenolic compounds assayed for their phytotoxicity on root growth of alfalfa, coumarin, trans‐cinnamic acid and o‐coumaric acid at 10^?3 m were most inhibitory. The type and amount of causative allelochemicals found in alfalfa plant parts were highly correlated with the results of the bioassay, indicating that the autotoxic effects of alfalfa plant parts significantly differed.     

Changes in Seed Yield and Quality with Maturity in Onion (Allium cepa L., cv. 'Early Cream Gold')

Development of onion (Allium cepa L., cv. ‘Early Cream Gold’) seed under cool climate conditions in Tasmania, Australia occurred over a longer duration than previously reported, but similar patterns of change in yield components were recorded. In contrast to previous studies, umbel moisture content declined from 85 to 67 % over 57 days while seed moisture content decreased from 85 to 31 %. Seed yield continued to increase over the duration of crop development, with increasing seed weight compensating for seed loss resulting from capsule dehiscence in the later stages of maturation. Germination percentage was high and did not vary significantly from 53 to 77 days after full bloom (DAF), but mean germination time declined and uniformity of germination increased significantly over the same time period. The percentage abnormal seedlings declined with later harvest date, resulting in highest seed quality at 77 DAF. The results of this study suggest that the decision to harvest cool climate onion seed crops before capsule dehiscence will result in a loss of potential seed yield and quality.     

Location of a high-lysine gene and the DDT-resistance gene on barley chromosome 7

Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans.     

A note on the origin of Kalanchoë x vadensis Boom & Zeilinga (Crassulaceae)

Summary K x vadensis is a hybrid of K. blossfeldiana and K. marmorata obtained after doubling the number of chromosomes.     

Simultaneous Determination of Four Phenolic Acids in Radix Salviae Miltiorrhizae Formula Granules by QAMS

[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...     

Avoidance of leaf rust fungi in wild relatives of cultivated cereals

Summary Avoidance of rust fungi that was based on poor appressorium induction was previously found in Hordeum chilense. In the present study 95 accessions of Triticeae were screened for avoidance of Puccinia hordei. The percentage of appressorium formation per germinated spore ranged from 6 to 90%. On none of the 41 accessions of Aegilops, Agropyron, Elymus, Secale, Thinopyrum or Triticum studied was the rate of appressorium formation lower than 25%. Lower rates of appressorium formation were, however, found on accessions of wild barley species Hordeum brachyantherum, H. marinum, H. parodii and H. secalinum. Its implications in cereal breeding are discussed.     

Variation in forage grasses as hosts of the root-knot nematode Meloidogyne naasi (Franklin) and selection for resistance in ryegrass

Summary Reactions of 13 grasses to Meloidogyne naasi varied with species; ryegrasses, fescues and their hybrids were generally susceptible and cocksfoot and timothy resistant. Marked variation in host resistance levels occurred between genotypes within cultivars.Selection of single plants, followed by tests on replicate tillers, identified resistant and susceptible genotypes in both Italian and perennial ryegrass cultivars. Resistant plants had few nematode-induced galls and fewer females and eggs than susceptibles. There was more or less continuous variation, with many genotypes intermediate between extremes of resistance and susceptibility. Selected resistant and susceptible genotypes are of use in assessing variation in nematode populations and as controls for breeding and selection programmes.     

Current and future strategies in breeding lentil for resistance to biotic and abiotic stresses

Lentil production is limited by lack of moisture and unfavorable temperatures throughout its distribution. Waterlogging and salinity are only locally important. Progress has been made in breeding for tolerance to drought through selection for an appropriate phenology and increased water use efficiency and in breeding for winter hardiness through selection for cold tolerance.The diseases rust, vascular wilt, and Ascochyta blight, caused by Uromyces viciae-fabae, Fusarium oxysporum f. sp. lentis, and Ascochyta fabae f. sp. lentis, respectively, are the key fungal pathogens of lentil. Cultivars with resistance to rust and Ascochyta blight have been released in several countries and resistant sources to vascular wilt are being exploited. Sources of resistance to several other fungal and viral diseases of regional importance are known. In contrast, although the pea leaf weevil (Sitona spp.) and the parasitic weed broomrape (Orobanche spp.), and to a lesser extent the cyst nematode (Heterodera ciceri), are significant yield reducers of lentil, no sources of resistance to these biotic stresses have been found. Directions for future research in lentil on both biotic and abiotic stresses are discussed.     

Breeding forage grasses for organic conditions

Herbage yield trials are necessary to test if candidate varieties are well suited for organic conditions. In order to elucidate a particular suitability for organic conditions, we run such trials in parallel under both organic and conventional conditions. Here, we report on second and third year results of the sowings 2004 and 2005. These trials are part of a targeted breeding programme for organic conditions. Irregular colonisation of pure grass plots with adventitious plants, in particular white clover, was recognized as a major constraint to the quality of the results obtained under organic conditions. The coefficients of variance in dry matter yield almost doubled when compared to conventional trials, and significant differences in annual yield among varieties were rare. However, when herbage yield was corrected for the estimated fraction of adventitious plant colonization at each cut, the number of instances with statistically significant differences for annual yield among varieties increased more than fourfold. Dry matter yields under organic and conventional conditions were significantly and positively correlated. However, analysis of variance showed a significant culture type by variety interaction for annual dry matter yield in 12 out of 24 trials. When diploid and tetraploid varieties of the same Lolium species were tested in one common trial, only tetraploid varieties were identified as being particularly well suited for organic conditions, while in these trials, the great majority of apparently poorly suited varieties were diploid. This suggests that breeding tetraploid Lolium varieties is promising when aiming at a favourable response to organic agriculture.     

The performance of double or mixed pollinations with compatible and self-incompatible or incongruous pollen of pear and apple

Summary Six pear and five apple trials were carried out to ascertain the outcome of combinations of compatible pollen (C) with self (S) or incongruous pollen (I) as to the pollination index (PI=seeds/pollinated flower). The PI of the mixture C+I (1:5) was consistently depressed as compared to that of the control C. The results of the double pollinations S/C and I/C were affected by the temperature at pollination; their PI's at <15°C were twice as high as those at >15°C, being well above and below the PI of C in the former and latter case respectively. The opposite was true for the C/S combination, the PI of which increased with the pollination temperature; the PI of C/I did not differ much from the PI of C, irrespective of temperature. The conclusion was reached that the interaction previously and presently found between compatible and self-incompatible pollen also exists to a fair extent between compatible and incongruous pollen. However, in pear neither the mentor nor the pioneer pollen technique proved to aid its hybridization with apple, the formation of self seed was not observed either. In apple the production of apple × pear hybrids was likewise doubtful, but the double pollinations S/C and C/S formed 4–10% self seed.