南瓜果胶提取工艺的优化研究

为建立适用于从南瓜中提取果胶的超声波辅助酸解工艺,采用单因素试验确定提取南瓜果胶的各因素水平,包括提取液酸度、料液比(g/mL)、浸提温度和浸提时间。利用L9(34)正交试验优化南瓜果胶的超声辅助酸解条件。结果表明,当超声辅助酸解条件为：提取液pH 2.0,料液比(g/mL)1:30,浸提温度75℃,浸提时间60 min,南瓜果胶得率最高,达到21.9%。     

超声波辅助盐析法提取橘子皮果胶的工艺研究

采用超声波辅助盐析法提取橘子皮中果胶。以果胶提取率为指标,确定了三氯化铁为果胶提取最佳盐,然后通过单因素试验和正交试验对超声波辅助盐析法提取橘子皮中果胶进行工艺研究。结果表明,在超声功率600 W,超声时间50 min,盐溶液液料比1∶0.15(m L∶g),盐析p H值6,盐析温度60℃的条件下橘子皮果胶提取率达到18.54%。     

响应面法优化莲子外皮总黄酮的超声辅助提取工艺

以莲子皮为原料,采用响应面试验设计优化超声波辅助提取莲子外皮中总黄酮的工艺条件。在单因素试验基础上确定以乙醇体积分数、料液比、浸提时间和超声功率为影响因素,以总黄酮的得率为响应值,根据Box-Behnken中心组合方法采用4因素3水平响应值试验设计优化。超声辅助法提取莲子外皮总黄酮的最佳工艺条件为乙醇体积分数70%,料液比1∶50,浸提时间35 min,超声功率125 W,总黄酮得率14.48%,与预测值14.92%接近。该提取工艺模型可靠,拟合度较高。     

超声波提取苦荞籽中多糖的工艺研究

采用超声波法从苦荞籽中提取多糖,苯酚—硫酸法测定其含量。通过单因素试验和正交试验分别考察了提取温度、时间、液料比、超声功率对苦荞多糖得率的影响。结果表明,葡萄糖含量在0.010 0~0.060 0 mg与吸光度线性关系良好,影响苦荞多糖得率因素的顺序为:液料比>提取时间>超声功率>提取温度。方差分析表明,液料比对多糖提取影响显著,时间影响较显著。最终确定超声波法提取苦荞籽中多糖的最佳工艺条件为:液料比40∶1,提取时间30 min,超声功率400 W,提取温度50℃,苦荞多糖得率为7.23%。     

超声辅助黑加仑多糖提取研究

研究了采用超声波辅助提取技术对黑加仑多糖进行提取,并对工艺条件进行优化。结果表明,超声波辅助提取黑加仑多糖的最佳工艺参数为:超声波功率140 W,超声波处理时间为30 min,恒温水浴浸提时间为1.5 h,料液比为0.5,黑加仑粗多糖得率1.8g/100 mL。通过正交试验进一步优化提取工艺条件,确定影响提取率的主次因素分别为料液比、超声波功率、超声波时间、水浴浸提时间。     

超声波辅助提取甘薯根颈多糖

甘薯根颈是甘薯生产中的大宗副产物,是提取功能性多糖的廉价资源。通过正交试验,对甘薯根颈多糖超声波辅助提取的影响因素进行了筛选和优化。结果表明：料液比、超声波频率、浸提温度、超声波功率、超声浸提时间等因素对提取率影响较大,较为合理的提取方案为：料液比1：30,超声波频率26kHz,超声波功率350W,浸提温度60℃,浸提时间30min。以此优化方案提取3次,提取物的平均提取得率为4.95%。通过棕色环试验、蒽酮-硫酸法、Fehling试剂法、双缩脲法证实提取物为多糖。     

超声波辅助法提取平菇水溶性多糖的工艺研究

研究超声波辅助法提取平菇水溶性多糖的优化工艺。以液固比、超声时间、提取时间、提取温度为考察因素,平菇多糖浸提率为考察指标,采用4因素3水平正交试验分别研究液固比、超声时间、提取时间、提取温度对平菇多糖浸提率的影响。结果表明,平菇多糖提取的最佳工艺为液固比30∶1,超声时间60 min,提取温度100℃,提取时间60 min。在此条件下,超声波辅助法提取水溶性平菇多糖的浸提率为17.12%。     

超声波辅助碱法提取蕨菜中水溶性膳食纤维

采用超声波辅助碱法提取蕨菜中的水溶性膳食纤维(SDF),通过单因素试验探讨料液比、超声功率、碱液质量浓度、提取温度4个因素对SDF得率的影响,再通过正交试验对提取工艺条件进行优化。结果表明,超声波辅助碱法提取蕨菜中的SDF最佳工艺条件为氢氧化钠质量浓度0.06 g/mL,超声功率120 W,料液比1∶30(g∶mL),提取温度65℃,实际测得SDF得率为36.01%。     

石榴渣多酚类物质提取工艺研究

以石榴渣为原料,研究了提取溶剂及其浓度、浸提温度、浸提时间和料液比对多酚提取效果的影响,并通过正交试验对4因素影响下的提取工艺进行了优化,确定了石榴渣多酚乙醇提取的最优工艺为:乙醇体积分数50%,浸提温度60℃,料液比1:20,浸提时间4h,以此优化工艺进行试验,一次提取得率为0.51%,二次提取得率为0.69%。超声波辅助提取的最佳处理时间为30min,提取2次,多酚得率为0.79%。原料干燥方式采用烘箱干燥较好。该工艺具有一定的实用性和可行性。     

超声波辅助碱法提取酒糟中纤维素和半纤维素

为了获取酒糟中优质的纤维素和半纤维素组分,采用超声波辅助碱提法进行同步提取。以酒糟为原料,以纤维素得率和半纤维素得率为指标,研究KOH溶液质量分数、浸提温度和超声波时间等因素对纤维素和半纤维素提取效果的影响,通过正交试验优化了提取条件。结果表明,在KOH溶液质量分数为7.5%,浸提温度为55℃,超声波时间为10 min条件下,酒糟中纤维素和半纤维素得率分别为38.72%和26.34%,说明采用超声波辅助碱法分离纤维素和半纤维素的工艺是可行的。傅里叶变换红外光谱分析表明,该工艺所提取的纤维素和半纤维素组分为预期产物,符合其结构特征。     

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.     

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.     

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...     

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.     

Pollen and pollination experiments. III. The viability of apple and pear pollen as affected by irradiation and storage

Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed.     

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...     

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.     

Optimization of Extraction Technology and Determination of Content of Total Phenols of Leaves in Acanthopanax giraldii Harms

[Objectives] To determine the optimum extraction technology for total phenols of leaves in Acanthopanax giraldii Harms.[Methods]The single factor test and ortho...     

Cytoplasmic male sterility,resistance to gall mite and mildew,and season of leafing out in black currants

Summary Cytoplasmic male sterility (cms) is described in the F₁ hybrids Ribes × carrierei (R. glutinosum albidum × R. nigrum) and R. sanguineum × R. nigrum. In backcrosses to R. nigrum, progenies with R. glutinosum cytoplasm were either all male sterile, or segregated for full male fertility (F) and complete (S) and partial (I) male sterility. Ratios of F:I+S suggested that two linked genes controlled cms, F plants being dominant for one (Rf ₁) and recessive for the other (Rf ₂).Segregation for cms in relation to three linded genes, Ce (resistance to the gall mite, Cecidophyopsis ribes), Sph ₃(resistance to American gooseberry mildew, Sphaerotheca mors-uvae) and Lf ₁(one of two dominant additive genes controlling early season leafing out) indicated that Rf ₁and Rf ₂were in this linkage group. The gene order and approximate crossover values appeared to be: % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqef0uAJj3BZ9Mz0bYu% H52CGmvzYLMzaerbd9wDYLwzYbItLDharqqr1ngBPrgifHhDYfgasa% acOqpw0xe9v8qqaqFD0xXdHaVhbbf9v8qqaqFr0xc9pk0xbba9q8Wq% Ffea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qqQ8frFve9Fve9Ff0dme% aabaqaciGacaGaamqadaabaeaafaaakeaacaWGdbGaamyzamaamaaa% baGaaiiiaiaacccacaGGWaGaaiOlaiaacgdacaGG0aGaaiiiaiaacc% caaaGaaiiiaiaacccacaGGGaGaamOuaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaaccdacaGGUaGaaiOmaiaacs% dacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaaaacaWGsbGaamOzaSGa% aGOmaOWaaWaaaeaacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccaaaGaamitaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccacaGGGaaaaiaadofacaWGWbGaamiAaSGa% aG4maaaa!6E4D!\[Ce\underline { 0.14 } Rf1\underline { 0.24 } Rf2\underline { } Lf1\underline { } Sph3\]. Crossover values of 0.36 for Ce-Lf ₁, and 0.15 for Lf ₁-Sph ₃were estimated from the relative mean differences in season of leafing out between seedlings dominant and recessive for Ce and Sph ₃.It is suggested that competitive disadvantage of lf ₁-carrying gametes and/or zygotes at low temperatures may be implicated in the almost invariable deficit of plants dominant for the closely linked mildew resistance allele Sph ₃. Poor performance of lf ₁- (and possibly lf ₂-) carrying gametes and young zygotes during periods of low temperature at flowering might also account for the liability of some late season cultivars and selections to premature fruit drop (running off).     

Screening techniques and sources of resistance to parasitic angiosperms

Parasitic angiosperms cause great losses in many important crops under different climatic conditions and soil types. The most widespread and important parasitic angiosperms belong to the genera Orobanche, Striga, and Cuscuta. The most important economical hosts belong to the Poaceae, Asteraceae, Solanaceae, Cucurbitaceae, and Fabaceae. Although some resistant cultivars have been identified in several crops, great gaps exist in our knowledge of the parasites and the genetic basis of the resistance, as well as the availability of in vitro screening techniques. Screening techniques are based on reactions of the host root or foliage. In vitro or greenhouse screening methods based on the reaction of root and/or foliar tissues are usually superior to field screenings and can be used with many species. To utilize them in plant breeding, it is necessary to demonstrate a strong correlation between in vitro and field data. The correlation should be calculated for every environment in which selection is practiced. Using biochemical analysis as a screening technique has had limited success. The reason seems to be the complex host-parasite interactions which lead to germination, rhizotropism, infection, and growth of the parasite. Germination results from chemicals produced by the host. Resistance is only available in a small group of crops. Resistance has been found in cultivated, primitive and wild forms, depending on the specific host-parasite system. An additional problem is the existence of pathotypes in the parasites. Inheritance of host resistance is usually polygenic and its transfer is slow and tedious. Molecular techniques have yet to be used to locate resistance to parasitic angiosperms. While intensifying the search for genes that control resistance to specific parasitic angiosperms, the best strategy to screen for resistance is to improve the already existing in vitro or greenhouse screening techniques.