分子蒸馏分提生产稻米油技术的研究

以脱胶后的四级稻米油为原料,在脱色的基础上利用分子蒸馏低温高真空二级分提游离脂肪酸,通过单因素和正交试验,优选出了最佳的二级分子蒸馏脱酸工艺条件。结果表明,蒸馏温度180℃,刮膜器转速420 r/min,物料速度40滴/min为最优的一级脱酸条件;蒸馏温度190℃,刮膜器转速420 r/min,物料速度40滴/min为最优的二级脱酸条件。在此条件下,可使油脂的酸值(KOH)小于0.15 mg/g,生产出的稻米油符合国家一级稻米油质量标准。     

基于分子蒸馏技术紫苏油α-亚麻酸纯化效果的研究

为了探究分子蒸馏技术纯化紫苏油α-亚麻酸的可行性,筛选紫苏油提取方法的基础上,考察了蒸馏温度、蒸馏压力、刮板转速和进料速度4个因素对分子蒸馏技术纯化α-亚麻酸效果的影响。结果表明,紫苏油最佳提取法为超临界CO₂萃取法,α-亚麻酸纯化的首要影响因素是蒸馏温度,其次是蒸馏压力,再次是进料速度,最后是刮板转速。最佳纯化工艺：蒸馏温度220℃,蒸馏压力0.07 mbar,刮板转速375 r/min,进料速度1.0 d/min,该工艺条件下α-亚麻酸纯度达到97.42%。该方法有效提高了紫苏油α-亚麻酸的纯度,为高纯度α-亚麻酸的研究和利用奠定了理论基础。     

分子蒸馏技术拆分陈皮挥发油及其GC-MS分析

以陈皮挥发油为研究对象,将其经过分子蒸馏拆分,得到不同馏分物,并分别对陈皮挥发油及所得馏分物进行气相色谱-质谱(GC-MS)分析。分子蒸馏分为二级,一级条件为:蒸发温度(30±0.2)℃,真空度(0.5±0.1)k Pa,刮膜器转速150~160 r/min;二级条件为:蒸发温度(60±0.2)℃,真空度(0.5±0.1)k Pa,刮膜器转速200~210 r/min;两次进样温度25℃,冷凝管温度10℃。结果表明,陈皮挥发油经二级分子蒸馏后总回收率为98.80%,其中一级轻组分(DF1)回收率为40.20%,二级轻组分(DF2)回收率为58.06%,二级重组分(RF2)回收率为0.53%。陈皮挥发油和各馏分物经过GC-MS分析后,确定25种化合物,主要为右旋萜二烯、α-萜品烯、萜品油烯等,但陈皮挥发油及各馏分物成分种类及相对含量差异明显,说明分子蒸馏技术能有效对陈皮挥发油成分进行拆分,可用于陈皮等挥发油的加工利用。     

柚核中柠檬苦素纯化工艺的研究

以乙醇为提取溶剂,采用超声波辅助提取柚核中柠檬苦素,通过正交试验对提取工艺进行优化,并采用大孔吸附树脂纯化柠檬苦素。最佳提取条件为:料液比1∶10,超声时间30min,乙醇体积分数70%,超声提取2次。4020型大孔树脂分离纯化提取液的最佳工艺条件为:吸附流速1mL/min,体积分数70%的乙醇洗脱,解吸流速0.7mL/min,纯化后得到柠檬苦素的质量分数达83.77%。该工艺分离纯化效果好,成本低。     

超临界流体CO_2萃取浙贝母花生物碱的工艺研究

通过单因素试验和正交试验优化,建立了浙贝母花生物碱超临界萃取的工艺参数,确定了最佳萃取工艺条件。结果表明,生物碱超临界萃取的最佳工艺条件为萃取温度70℃,萃取压力35 MPa,萃取时间50 min,夹带剂流速0.15 mL/min,在此条件下总生物碱的理论提取率为3.52±0.15 mg/g。     

响应面法优化分子蒸馏纯化废次烟末中香味成分的研究

以废次烟末为原料,采用分子蒸馏技术对其超临界CO2提取物的香味成分进行分离纯化研究,以纯化物得率和感官品质为评价指标,分别考查了蒸馏压力、蒸馏温度、进料速率对其影响,采用Box-Behnken响应面法对纯化工艺的关键参数进行优化。结果表明,蒸馏温度、蒸馏压力对得率和感官品质的影响显著,得到的最优纯化工艺条件为蒸馏温度61℃,蒸馏压力111 Pa,进料速率11 m L/min,得率为1.54%,感官品质最佳。     

提高大蒜精油得率的酶控工艺研究

大蒜精油具有多方面的药用价值和保健作用,因此已经成为国内外竞相研究的热点课题。该研究从影响蒸馏前蒜氨酸酶活性的酶解条件入手,探究大蒜精油提取率的最佳工艺条件,得出最佳的工艺条件是酶解时间2．5h、酶解温度55℃、pH值6．6、蒸馏时间45min、蒸馏电压120V。实验结果表明,良好的酶控条件可以大大提高大蒜精油的产出率,最高可达0．57％。     

黄花菜多酚提取工艺及抗氧化作用的研究

探讨黄花菜多酚最佳提取工艺及抗氧化作用。结果表明,黄花菜多酚最佳提取工艺为:提取时间60min、乙醇浓度55%、料液比1∶15、提取温度35℃;在此条件下,多酚得率为28.89%。抗氧化试验表明黄花菜多酚对羟自由基、超氧阴离子自由基、DPPH自由基均具有一定的清除作用,其半抑制率(IC50)分别为0.1176mg/mL、0.1638mg/mL和0.1593mg/mL,且清除率与黄花菜多酚浓度成量效关系。     

柚皮柠檬苦素的提取及其杀虫活性研究

为了探究柚皮中柠檬苦素的最佳提取工艺及其杀虫活性,采用正交试验对柚皮中柠檬苦素的提取工艺进行优化,利用得到的柠檬苦素对夹竹桃蚜虫、吹绵蚧和菜蝽喷雾进行杀虫试验。结果表明：超声波提取法、二氯甲烷和丙酮水浴提取法从10 g柚皮中提取到的柠檬苦素分别是0.9700、1.5860、1.6000 g;二氯甲烷水浴提取法对柚皮中的柠檬苦素提取率为6.08%。10 mg/mL的柠檬苦素能将供试害虫全部杀死,0.625 mg/mL的柠檬苦素依然有较高的杀虫活性。回流法提取柚子皮中的柠檬苦素时,最佳提取工艺是：二氯甲烷为提取溶剂,液料比为1:12,回流提取2次,每次2 h,温度50℃;得到的柠檬苦素对3种供试害虫有较强的杀虫活性。     

超声波辅助提取沙田柚种籽油工艺优化研究

为了优化超声波提取沙田柚种籽油的工艺参数。在单因素试验基础上,通过采用响应面法,对超声波辅助时间、液料比、超声波功率比和温度进行了优化。结果表明,最佳工艺参数为：提取溶剂为异丙醇、时间为40 min、超声波功率比为73.77%、液料比为5.9:1(mL/g)、提取温度为47.39℃。在此最佳工艺参数下,沙田柚种籽油的提取率达38.82%。     

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.     

Present status and future strategy in breeding faba beans (Vicia Faba L.) for resistance to biotic and abiotic stresses

Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses.     

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.     

Water Extraction Process of Chinese Herbal Compound Man Gan Ning

[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...