皱皮木瓜果实发育后期品质变化及其成熟阶段的划分初探

以湖北长阳产皱皮木瓜为材料,测定果实发育后期果实鲜质量、果长、果径、果色、果实硬度以及果肉干物质量、可溶性糖含量、总酸含量和总黄酮含量等品质指标的动态变化,划分不同成熟阶段,为判断果实适宜采收期、实现优质生产提供理论参考。结果表明:(1)皱皮木瓜果实发育后期果实鲜质量、果长、果径、果肉干物质量和可溶性糖含量均呈现上升趋势;果色由绿色、黄绿色渐变为淡黄色到黄色;果实硬度、果肉总酸和总黄酮含量呈先上升后下降趋势。(2)各品质指标快速变化的时间区域存在差异,果实鲜质量在花后105~150d增加较快,果色在150d后逐渐变黄,果实硬度在花后135~165d快速下降,果肉总酸、总黄酮含量则在花后105~120d快速增加至峰值。(3)根据主成分分析结果和各品质指标的变化特点,可初步将皱皮木瓜果实发育后期划分为未成熟(花后105d之前)、早期成熟(花后120~150d)和成熟(花后165~180d)3个阶段。研究表明,随着果实成熟度的提高,皱皮木瓜果实鲜质量、果色、果肉干物质量、可溶性糖含量等指标不断升高,果实硬度逐渐下降,其食用加工品质不断提升,而在早期成熟阶段(花后120~150d)果实的药用品质则相对较高。     

花椒果皮中总黄酮与多酚的积累及其抗氧化活性研究

以7年生花椒为试材,研究不同生长时期花椒果皮的总黄酮、总多酚含量的变化以及二者与抗氧化能力的关系.结果显示:(1)在花椒果实发育过程中,花椒果皮黄酮与多酚均有积累,总黄酮含量随果实的成熟程度不断增加,于成熟期(8月1日)黄酮含量达到最大值(164.14 mg/g);但多酚含量在果实发育早期迅速上升,于6月30日达到最大值(77.17 mg/g)后快速下降,至成熟期(8月1日)多酚含量为46.23 mg/g.(2)不同时期的花椒果皮均具有还原力及羟基自由基清除能力,且二者随果实生长的增加而提高,且总黄酮、多酚含量均与还原力和羟基自由基清除能力之间呈显著正相关关系,相关系数分别为0.977、0.960和0.917、0.933.研究表明,成熟花椒果皮中总黄酮含量达到最高,多酚含量也较高,而且黄酮和多酚类物质是花椒果皮抗氧化活性的主要功效成分.     

荔枝果实发育过程中内源多胺含量的变化

荔枝果实中多胺含量以亚精胺(Spd)最高,腐胺(Put)其次,精胺(Spm)最低,三者分别于花后7 d和28 d各出现1个高峰.果皮、假种皮和种子中总多胺含量以各自发育初期为最高,随后急速下降,快速膨大期间的变化则不大.花后0～21 d,单果中Put、Spd和Spm含量最低;花后28 d,出现第1个小高峰;果实快速膨大期Spd含量急剧升高,Put和Spm升高较慢.     

树葡萄果实功能成分分析北大核心CSCD

为了解树葡萄果实中功能成分的含量,本实验分别采用分光光度法测定树葡萄果实黄酮和花青索含量,Folin．Ciocaileu比色法测定多酚含量。研究结果表明：树葡萄的果皮、果肉和种子中都含有花青素、多酚和黄酮,但花青素在整个果实中含量最低,而果肉的花青索、多酚和黄酮的含量都极显著低于果皮和种子。果实中果皮的花青素含量相对于其他两个部位较高,达1．2391u;种子总多酚含量最高达19．952mg／g,其次是果皮,果肉总多酚含量最低,仅0．1333mg／g;果皮总黄酮含量最高达6．2011mg/g,其次是种子,果肉总黄酮含量最低,仅0．5800mg/g。由此可见,树葡萄果实果肉的3种功能成分含量最低,花青素和总黄酮以果皮含量最高,总多酚以种子含量最高。     

苹果新品种‘瑞阳’果实主要特性研究

该研究以红色晚熟苹果新品种‘瑞阳’及其母本‘秦冠’、父本‘富士’为试验材料,分析各品种果实发育过程中的生长动态、色泽变化以及采收期对其果实品质的影响,为品种栽培管理和推广应用提供参考。结果表明:(1)在果实生长发育期,‘瑞阳’单果质量的变化与双亲接近,单果质量的日增长高峰出现在花后105d,果实发育前期纵径增长较大,果形指数大,在发育后期果形指数降低,至成熟时果形指数达到0.86,介于父母本‘秦冠’和‘富士’之间。(2)套袋处理使果实着色期的色泽参数a*值和花青苷含量上升,但品种间存在差异,套袋处理对‘瑞阳’的色泽参数a*值和花青苷含量影响不大。(3)随果实采后天数的延长,各采收期‘瑞阳’果实淀粉指数逐渐上升,硬度和可滴定酸逐渐下降,而可溶性固形物含量先上升后下降;‘瑞阳’果实在花后174d采收时,果实的硬度和可滴定酸下降均较少,且果实可溶性固形物含量保持在较高水平,能较好地维持该品种的果实品质。研究发现,‘瑞阳’苹果果实膨大期出现在花后105d前后,果实套袋对其表面色泽和花青苷含量影响不大,在陕西渭北以花后174d前后采收为宜。     

砀山酥梨石细胞发育过程中PPO酶学特性及其cDNA片段克隆

以砀山酥梨果实为材料,研究了影响石细胞形成的木质素合成酶-多酚氧化酶(polyphenol oxidase,PPO)的酶学特性,并对PPO基因进行了克隆.结果表明,在砀山酥梨果实发育的过程中,PPO活性在花后27 d和47 d出现高峰,早于木质素含量高峰(花后47 d、61 d)和石细胞团含量高峰(花后51 d),且P...     

HPLC-DAD法测定血满草中熊果酸和齐墩果酸的含量(英文)

建立了HPLC-DAD法测定血满草中熊果酸和齐墩果酸含量,并进行方法学考察。采用HPLC-DAD进行分析,fusion-RP C18柱(4.6 mm×250 mm,4μm),甲醇-0.2%磷酸水溶液(90∶10)为流动相,检测波长210 nm,体积流量1.0 mL/min。同时采用微波辅助提取、回流提取、索氏提取、冷浸提取、超声提取五种方法对血满草中熊果酸和齐墩果酸含量进行测定并比较不同方法所得结果的差异,还比较了血满草不同部位中熊果酸和齐墩果酸的含量差异。测定结果表明熊果酸进样量在3.6～8.4μg范围内,齐墩果酸进样量在3.2～16μg范围内,呈良好线性关系。血满草中熊果酸和齐墩果酸平均回收率分别为98.3%和101.4%(n=5),相对标准偏差分别为1.13%和0.72%(n=5)。五种方法比较得出索氏提取得熊果酸和齐墩果酸含量最高;血满草花中熊果酸和齐墩果酸含量最高,而根中含量最低。该方法使血满草中熊果酸和齐墩果酸达到基线分离,操作简便,结果稳定可靠。     

桃果实不同发育时期细胞内糖酸分布对甜酸风味的影响

为了解桃果实发育过程中细胞内糖酸的分布、变化规律对果实甜酸风味的影响,采用区室分析方法研究了‘白凤’桃(Prunus persica‘Hakuho’)果实不同发育时期细胞内糖酸组分、含量及其分布对甜酸风味的影响。结果表明,成熟果实中(花后100 d)可溶性糖(蔗糖、葡萄糖、果糖和山梨醇)在液泡、细胞质和细胞间隙中的含量分别为27.3、11.6、9.0 mg/g,有机酸(苹果酸、柠檬酸、奎宁酸和莽草酸)含量为2.09、0.94、0.35 mg/g;未成熟果实中(花后60 d)可溶性糖在液泡、细胞质和细胞间隙中的含量分别为0.97、2.2、2.3 mg/g,有机酸含量为0.25、0.44、0.82 mg/g。‘白凤’桃果肉细胞内不同的糖酸分布对成熟果实的甜酸风味具有显著影响,而对未成熟果实影响较小。成熟果实中糖酸在液泡、细胞质和细胞间隙三者之间的分布差异可能是导致果实甜度变化的主要原因。     

219份枣种质资源果实三萜酸含量分析

以219份枣种质脆熟期果实为试材,采用超高效液相色谱(UPLC)法检测不同枣种质果实中的山楂酸、桦木酸、齐墩果酸和熊果酸4种三萜酸组分含量,并进行描述统计分析、相关性分析和聚类分析,进而筛选三萜酸含量较高的优特异种质。结果表明:(1)枣果中总三萜酸(TTA)含量的变化范围95.72~737.82μg·g^-1,平均值306.83μg·g^-1,变异系数为29.02%,含量最高的为‘大荔小圆枣’。4种组分以山楂酸含量最高,其次为桦木酸,齐墩果酸和熊果酸含量较低,各组分在不同枣种质中都存在丰富的遗传多样性,其中熊果酸变异系数最高(60.75%)。(2)正态性检验结果表明,各种质的山楂酸、桦木酸和总三萜酸含量服从正态分布,齐墩果酸和熊果酸含量不服从正态分布。(3)相关性分析结果显示,总三萜酸含量与4个组分均呈极显著正相关关系,组分间也存在相关性,山楂酸含量与桦木酸呈极显著正相关关系,桦木酸含量与齐墩果酸呈极显著正相关关系,齐墩果酸含量与熊果酸呈极显著正相关关系。(4)聚类分析将219份枣种质划分为4大类群,分别为熊果酸含量最高的类群,齐墩果酸和熊果酸含量较高类群,各组分中低含量类群以及山楂酸、桦木酸和总三萜酸含量较高类群。(5)筛选出13份各组分或总三萜酸含量较高的优特异种质,为枣三萜酸相关功能产品的开发提供原料选择。     

反相高效液相色谱法测定不同采收期柿叶芦丁、齐墩果酸的含量

研究柿叶中芦丁、齐墩果酸随月份动态变化规律。用回流提取法制备同一来源、不同月份柿叶样品,采用RP-HPLC法,以芦丁为对照品,测定同一年中5月到11月7份样品中芦丁的含量。用索氏提取法制备不同月份柿叶齐墩果酸样品,采用RP-HPLC,以齐墩果酸为对照品,测定同一年中5月到11月7份样品中齐墩果酸的含量。结果显示:7月和10月采收的柿叶中芦丁和齐墩果酸的含量较高。10月(采收柿子果实后)采收的柿叶有可能作为制备芦丁、齐墩果酸的原料使用。     

Fluctuation in levels of endogenous plant hormones in ovules of normal and mutant cotton during flowering and their relation to fiber development

The contents of indole-3-acetic acid (IAA), gibberellins (GAs), abscisic acid (ABA), and cytokinins were determined in ovules of normal cotton (Tm-1) and a kind of fiber differentiation mutant (Xin) before and after flowering by enzyme-linked immunosorbent assays. It was found that 24 h before flowering, a peak of IAA content was observed in ovules of Tm-1, whereas in ovules of Xin, a low level of IAA was determined. From –1 day (1 day before flowering) to +3 days (3 days after flowering), GA₁₊₃ levels in ovules of Xin were 40–70% lower than those of Tm-1; GA₄₊₇ levels were very low, and there was no visible difference in GA₄₊₇ content between normal and mutant cotton. The ABA content in ovule of Tm-1 decreased by 70% 3 days after flowering, whereas that of Xin only decreased by 20%. The levels of cytokinins in ovules of Tm-1 decreased after flowering, and those of Xin kept up a steady increase.Abbreviations IAA indole-3-acetic acid - GA gibberellin - ABA abscisic acid - ELISA enzyme-linked immunosorbent assay - FW fresh weight - PBS phosphate-buffered saline - iPA isopentenyladenosine - ZR zeatin riboside - DHZR dihydrozeatin riboside - CTK cytokinin     

Protein Synthesis in Cotyledons of Pisum sativum L: I. Changes in Cell-Free Amino Acid Incorporation Capacity during Seed Development and Maturation

The changes in protein content of pea cotyledons have been followed during the period from 9 to 33 days after flowering. Initially protein content increased gradually with a rapid period of deposition occurring between days 21 and 27 after flowering. After the 28th day the rate of accumulation of protein declined as the seed dehydrated and matured. At maturity the pea cotyledon contained approximately 25% protein which was divided into albumins and globulins in the ratio of 1:1.4.     

Developmental Changes in the Amylose Content of Endosperm Starch of Barley (Hordeum vulgare L.) during the Grain Filling Period after Anthesis

Large and small starch granules were isolated and characterized from kernels of non-waxy (Bozu) and waxy (Yatomi mochi) barleys at their developmental stages of 8, 16, 28 and 40 days after flowering. The amylose content of the large and small granules of the non-waxy barley starch, as determined by the blue value and enzyme-chromatography, increased with the increasing age of the endosperm. Large granules of the non-waxy barley at any given developmental stage contained more amylose than small granules at the same stage, as in the case of mature non-waxy barley starches. Large granules of either the non-waxy or waxy barleys at any given developmental stage had a lower fraction III: fraction II ratio, one of the structural characteristics of amylopectin, than did small granules of the same cultivar at the same developmental stage. The amylose content in large granules of the waxy barley appeared to increase with the increasing age of the endosperm. The amylose content in small granules of the waxy barley at 8 days after flowering was 10%, although that at 16 and 28 days after flowering and at maturity was only 0~1%.     

Enzymes of carbohydrate metabolism in the developing rice grain

The levels of reducing and nonreducing sugars, starch, soluble protein, and selected enzymes involved in the metabolism of sucrose, glucose-1-P, and glucose nucleotides were assayed in dehulled developing rice grains (Oryza sativa L. line IR1541-76-3) during the first 3 weeks after flowering. The level of reducing sugars in the grain was highest 5 to 6 days after flowering. The level of nonreducing sugars and the rate of starch accumulation were maximum 11 to 12 days after flowering, when the level of soluble protein was also the highest. The activities of bound and free invertase, sucrose-UDP and sucrose-ADP glucosyltransferases, hexokinase, phosphoglucomutase, nucleoside diphosphokinase, and UDP-glucose and ADP-glucose pyrophosphorylases were high throughout starch deposition, and were maximum, except for nucleoside diphosphokinase which did not increase in activity, between 8 and 18 days after flowering. Soluble primed phosphorylase and ADP glucose-α-glucosyltransferase (starch synthetase) were both present during starch accumulation. Phosphorylase activity was at least 2-fold that of soluble starch synthetase but the synthetase followed more closely the rate of starch accumulation in the grain. The activity of starch synthetase bound to the starch granule also increased progressively with increased starch content of the grain.     

早实核桃脂肪积累与酶活性动态及其相关性

以绿岭和绿早2个早实核桃品种为试材,对开花50 d后不同发育时期核仁的脂肪含量与3种相关的酶活性动态进行研究,分析不同发育时期影响核桃脂肪含量的关键酶.结果表明: 2个品种的核仁脂肪积累动态一致,核仁在开花后50 d开始固化,花后60～90 d核仁脂肪含量迅速增加,花后90～120 d增长幅度变缓,花后120～130 d脂肪含量停止增长.利用Logistic模型对核桃脂肪积累进程进行拟合(P<0.01),绿岭脂肪积累盛期为开花后57.8～85.8 d,绿早为开花后67.4～92.1 d.乙酰辅酶A羧化酶(ACCase)、6-磷酸葡萄糖脱氢酶(G6PDH)和丙酮酸激酶(PK)活性均在花后50～100 d呈上升趋势,随后酶活性呈下降趋势.核仁脂肪含量与ACCase活性呈显著正相关;脂肪积累速率与PK活性呈显著正相关;不同发育时期脂肪含量与酶活性的相关性不同.花后50～100 d是核桃核仁脂肪合成旺盛的时期,此时加强田间栽培管理可以提高脂肪含量.在核桃脂肪合成前期G6PDH是影响脂肪含量的主要酶,PK活性影响丙酮酸形成,从而间接影响脂肪的合成.ACCase活性影响了最终的脂肪含量,并在脂肪合成的各个时期均起到重要的调节作用,是影响核桃脂肪合成的关键酶.     

非洲菊光合特性研究

对温室栽培条件下非洲菊(Gerbera hybrida var. diablo)开花前、开花期、开花后三个生育期的光合特性进行初步探讨。结果表明,开花前CO₂浓度为600μmol/mol时,净光合速率(Pn)为8.23 CO₂μmol/m²·s,比在大气CO₂浓度下高27.1%;开花期非洲菊的表观量子效率较小,比开花前、开花后分别低40.0%和37.2%,CO₂补偿点为59μmol/mol,比开花前、开花后分别低45.8%和55.9%,三个生育期的CO₂饱和点差别不明显,开花后的羧化效率(CE)较低;开花后叶片叶绿素含量下降,但三个生育期的净光合速率相近(6.0CO₂μmol/m²·s左右)。非洲菊的光合日变化在晴天呈不太明显的"双峰型",最大净光合速率出现在11:00左右,为7.77 CO₂μmol/m²·s,次峰值出现在1500左右,小于首峰值。     

Fatty acid changes in Hibiscus esculentus tissues during growth

Lipids were isolated from roots, stems, cotyledons, leaves, buds, flowers, pods and seeds of okra (Hibiscus esculentus) at different stages of plant growth from germination to seed formation and their fatty acid compositions analysed. The lipid contents of roots and stems were 1–3%, cotyledons 3.7–9%, leaves 2.5–5.1% and seeds 2.2–20.2%. Palmitic, linoleic and linolenic were the main fatty acids present in all tissues at all stages, but their relative proportions varied. Cyclopropene fatty acids (CFA) were present at some stages in roots and seeds. In the roots their formation coincided with bud formation (35 days after sowing) and their content reached a maximum (12.8%) seven days after flowering. CFA were present in maturing seeds from 31 days after flowering and occurred as dihydro derivatives throughout. Dihydro derivatives of the CFA were absent in all other tissues. Heptadecenoic acid was present (0.4–1.3%) in root lipids at all stages and in the stem lipids (0.4–1.2%) in the initial stages and after flowering.     

beta-Conglycinins in Developing Soybean Seeds

The temporal sequence of development of the major proteins of seeds of soybean (Merr.) has been studied during development of cotyledons from flowering to maturity. A well-defined difference occurred in the times of appearance and the periods of maximum accumulation of α, α′-, and β-subunits of betaconglycinin. Whereas α- and α′-subunits appeared 15 to 17 days after flowering, accumulation of β-subunit did not commence until 22 days after flowering. Such alterations in subunit composition infer that changes also occurred in the amino acid composition of betaconglycinin during maturation, particularly in the content of methionine which is low in the β-subunit.     

豌豆种子发育过程中DNA和RNA的变化

实验结果表明：豌豆种子发育过程中单粒鲜重、ＤＮＡ和ＲＮＡ含量都随开花后日数增加而增加。其中豌豆开花第２１天,ＲＮＡ含量达最高峰,拖尾现象消失而趋于单一带区,ＤＮＡ的迁移率也降到最低,从而确定出豌豆开花后第２１天是基因转录活动降低的转折点,为种子蛋白质基因工程研究提供参考。     

Role of gibberellins in stem elongation and flowering in radish

The relationship among gibberellins, CCC, vernalization, and photoperiod in the flowering response of radish, Raphanus sativus L., cv. Miyashige-sofuto, was studied. The optimal condition for flowering was vernalization and a 16-hour photoperiod; GA₃ had no additional effect. Gibberellin A₃ (60 μg total) was not able to induce flowering in nonvernalized plants grown on 8-hour days, but it did increase the percentage of nonvernalized plants that flowered under long days from 60 to 100.

Gibberellin content of vernalized seedlings increased within the first 24 hours after seedlings were transferred to the greenhouse. Content reached a peak in the first 4 days after transfer and thereafter remained constant. Essentially no gibberellin was found in 2 day-old non-vernalized (control) seedlings of comparable size to the vernalized ones. Gibberellin content in the controls reached a peak on the fourth day of growth in the greenhouse; thereafter, it decreased steadily.

Bolting was inhibited slightly by CCC when applied during vernalization; it was almost completely inhibited when CCC was applied after seed vernalization. Extraction experiments revealed that CCC actually reduced the gibberellin content when applied during or after vernalization. The dwarfing agent, however, had essentially no effect on flowering. We concluded that gibberellins likely play a direct role in bolting of `Miyashige-sofuto' radish, but probably are not directly functional in initiating flowering.