气质联用分析黄河滩枣冰酒中香气成分

采用气相色谱-质谱联用对黄河滩枣冰酒中的香气成分进行分析,并运用面积归一法确定各组分的相对百分含量。结果表明,从黄河滩枣冰酒中分离鉴定出36种香气成分,其中醇类化合物相对百分含量为38.12%,是黄河滩枣冰酒中含量最多的一类化合物;其次为酯类(相对含量为29.57%)、酸类(相对含量为28.54%)。冰酒中主要的香气成分为异戊醇(19.82%)、乙酸(18.56%)以及乙酸乙酯(9.41%),这些物质共同赋予了黄河滩枣特殊的风味和品质。     

不同酵母发酵对柿子酒、柿子醋风味的影响

以盘山磨盘柿为试验材料,分别接种两种不同酵母菌发酵酿造柿子酒和柿子醋,通过顶空固相微萃取(HS-SPME)与气相色谱-质谱联用(GC-MS)技术研究不同酵母菌发酵对柿子酒、柿子醋香气成分的影响.结果表明:马克斯克鲁维酵母发酵的柿子酒与酿酒酵母发酵的柿子酒相比,香气物质的总含量增加了56.42％.其中,月桂酸乙酯、正癸酸、辛酸乙酯、乙酸苯乙酯、癸酸乙酯的含量提高明显,分别提高了177.91％、163.16％、137.36％、147.13％、110.37％.与酿酒酵母相比,马克斯克鲁维酵母发酵的柿子酒和柿子醋中均新增了一些高级醇、酯及酮类物质,由此可见,马克斯克鲁维酵母发酵可有效提高柿子酒、柿子醋中挥发性香气物质的种类和含量,起到提高柿子酒和柿子醋香气品质的作用.     

HS-SPME-GC-MS法分析西州蜜25号甜瓜贮藏中的香气成分

以海南产网纹甜瓜西州蜜25号为试材,采用顶空固相微萃取气质联用技术(HS-SPME-GCMS)分析甜瓜在5℃低温贮藏过程中的香气成分及变化规律。结果表明,西州蜜25号甜瓜样品最佳前处理条件为:萃取头为二乙烯基苯/碳分子筛/聚二甲基硅氧烷(50/30μm DVB/CAR/PDMS),最佳富集香气的样品量6 g,萃取温度40℃,萃取时间30 min;西州蜜25号甜瓜香气中共检测到54种化合物,其中酯类38种、醇类10种、醛类4种、酮类1种和烷烃类1种;在贮藏过程中,香气成分的相对含量及种类在不断变化,酯类化合物和醇类化合物的相对含量总体升高,醛类和酮类化合物的相对含量总体降低;一直持有的香气成分有23种,贮藏0、11、31 d时,23种香气的相对含量之和占总香气成分相对含量分别是87.18%、81.41%和82.63%,初步认为23种香气成分对果实的香气贡献最大。     

4个苹果属野生种果实香气成分HS-GC-MS分析

利用顶空固相微萃取和气相色谱－质谱联用技术分析了八棱海棠(Malus robusta (Carr.) Rehd)、东北黄海棠(M. prunifolia)、武山变叶海棠(M. toringoides)及西府海棠(M. micromalus)果实香气成分,为苹果属野生资源的评价与利用提供基本资料。结果表明：4个苹果属野生种与对照苹果品种‘红星’、‘富士’相对含量最高的化合物均是(E)-2-己烯醛,共有的相对含量较高化合物有己醛、(E,E)-2,4-己二烯醛和乙醇;4个苹果属野生种共有的化合物有乙醇、己醇、(Z)-3-己烯-1-醇、己醛、(Z)-3-己烯醛、(E)-2-己烯醛、(E,E)-2,4-己二烯醛和4-苯甲酸-2H-吡喃-3-酮,但4者主要香气成分及其相对含量仍存在一定差异。尽管野生种与两个对照品种相对含量最高的化合物类别均是醛类,但它们之间香气成分类别及其相对含量仍存在差异。(E)-2-己烯醛可能是苹果属植物果实香气的典型成分,对其特有风味的形成可能具有重要作用。     

不同酿酒酵母对菠萝酒香气品质的影响分析

以菠萝皮渣为原料,选取CY3079,DV10,K1和QA23这4种酵母进行发酵,利用固相微萃取和气质联用技术分别对4种菠萝酒主发酵结束后的香气成分进行比较。结果表明,酒液中共检测出38,30,26,26种香气成分,其中QA23酵母发酵的菠萝酒香气成分种类较多,菠萝酒的香气成分以酯类和醇类为主,QA23,K1,DV10和CY3079中酯类相对含量分别为51.71%,45.01%,30.27%,19.86%;主要的酯类成分为乙酸异戊酯、正己酸乙酯、辛酸乙酯、癸酸乙酯和月桂酸乙酯,酒液中除乙醇外,2,3-丁二醇、(2R,3R)-(-)-2,3-丁二醇和苯乙醇含量较高,其中苯乙醇含量最高,分别达到11.74%,12.15%,14.98%,18.27%。     

广佛手香气成分分析

采用气质联用技术(Gas chromatography-mass spectrometer,GC-MS),对广佛手的香气成分进行分析。结果表明,广佛手香气成分主要由烯烃类和醛类组成,分别占香气成分相对百分含量的24.95%和28.97%。     

不同干燥工艺对枣粉挥发性香气成分的影响

以新疆哈密红枣为原料,通过喷雾干燥和冷冻干燥工艺方法制取枣粉,采用色差仪和固相微萃取-气相色谱质谱联用技术,对两种红枣粉的色泽进行评定,并对其香气成分进行检测分析,研究不同干燥工艺对枣粉香气成分的影响。结果表明:冷冻干燥的枣粉色泽呈淡绿色,喷雾干燥的枣粉色泽呈淡黄色;从冷冻干燥枣粉、喷雾干燥枣粉和原枣浆中分别检测出挥发性化合物42、52和43种,均含有醛类、酮类、酸类、酯类、醇类、烷烃类、烯烃类、芳香烃类及少量未知物,其有效组分分别占总挥发物质的52.37%、72.07%和56.44%,且喷雾干燥枣粉的酯类和酸类化合物显著多于原枣浆,冷冻干燥枣粉组分无明显减少,其醇类物质所占总有效组分比例显著增加,且枣的特征香气成分相对较稳定。     

两种砧木对布鲁克斯大樱桃果实芳香成分的影响

【研究目的】为研究考特和吉塞拉作为砧木对甜樱桃果实香气成分的影响。【方法】采用顶空微萃取技术提取成熟期果实的香气成分,经气相色谱质谱联用仪进行测定分析。【结果】不鲁克斯甜樱桃的香气成分共检测到61种,主要成分为醛类、醇类和酯类。从布鲁克斯（吉塞拉）中检测出38种香气成分占总峰面积的59.66 %,相对百分含量较高的是乙醇、乙酸己酯、1-乙基－3－甲基苯、苯乙烯、1,2,3－三甲基苯。从布鲁克斯（考特）中检测出30种香气成分占总峰面积的64.74 %,相对百分含量较高的是乙醇、（E)2－己烯－1－醇、3-异丁基-6-烯-1-辛醇、乙酸己酯。【结论】吉塞拉和考特作为砧木对布鲁克斯甜樱桃果实中香气成分的影响较明显,在香气种类上吉塞拉砧木具有明显优势。（E)2－己烯－1－醇、己醛、乙酸己酯、(E)-丁酸－2－己烯酯、3-异丁基-6-烯-1-辛醇是不鲁克斯甜樱桃成熟果实的特征香气成分。     

不同乌龙茶品种(品系)鲜叶香气组分的初步研究

研究旨在分析不同乌龙茶品种（品系）鲜叶香气组分,揭示乌龙茶适制性品种（品系）的香气物质基础,为选育乌龙茶适制性品种以及加工高香型乌龙茶提供理论依据。采用同时蒸馏萃取法(SDE)提取茶鲜叶香气,气相色谱-质谱联用(GC-MS)测定其香气组分,分析比较14 个乌龙茶品种（品系）的香气化学成分及含量。GC-MS分析结果表明,样品中共检测出香气成分140 种,共有的香气成分有25 种。各品种（品系）均以醇类含量最多（14 个样品平均相对含量为39.92%）,其次为脂肪酸类(22.71%)、醛类(15.67%)、酮类(5.74%)、脂类(4.00%)、杂氧化合物(2.83%)、碳氢化合物(2.27%),含量最少的是含氮化合物(0.20%)。可见,醇类、脂肪酸类和醛类对乌龙茶品种（品系）鲜叶香气起主要作用。     

南果梨酒发酵工艺优化及其主要香气成分变化分析

以南果梨为试材,在单因素试验的基础上,通过正交试验优化南果梨酒发酵工艺,并研究其发酵前、发酵结束后以及陈酿后香气成分的变化。结果表明,南果梨酒最佳发酵工艺为：酵母菌接种量5%,发酵pH 4.0,调整初始糖度18%,发酵温度24 ℃,按此工艺发酵制得的南果梨酒感官品质评分为88分,酒精度为12.14%,其香气浓郁,口感圆润,色泽较佳。对南果梨酒发酵及陈酿过程中的香气成分进行测定发现,南果梨酒香气成分的种类和相对含量在发酵过程中变化明显,发酵初始检出香气成分14种,占检出挥发性成分的56.67%;发酵结束检出香气成分23种,占检出挥发成分的91.79%;陈酿后检出香气成分23种,占检出挥发成分的79.37%。     

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.     

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...     

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.     

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.     

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.