Crocin and geniposide profiles and radical scavenging activity of gardenia fruits (Gardenia jasminoides Ellis) from different cultivars and at the various stages of maturation

The major components of gardenia fruits are geniposide and water soluble pigment crocins. In this study, we investigate crocins and geniposide profiles of gardenia fruits from different cultivars and at the various stages of maturation. DPPH scavenging activity of gardenia fruits from different cultivars and at the various stages of fruit maturation was also assayed. Quantitative determination of crocins in the gardenia at the various stages of maturation revealed a significant increase when ripening. However, geniposide content was negatively correlated with ripening stages. A significant difference was observed when comparing crocin content of different gardenia from various cultivars and geniposide content also showed marked variety. Current study indicated no relationship between crocin and geniposide content in gardenia fruits at the various stages of maturation and DPPH radical scavenging activity. Data showed that, although crocins feature markedly less DPPH scavenging activity than gardenia ethanol extract, total crocin content of gardenias collected in various cultivars correlate, to a certain degree, with radical scavenging effects of the Chinese traditional medicine (r = 0.75).     

HPLC研究油橄榄叶中橄榄苦苷的含量变化规律

研究了油橄榄叶中橄榄苦苷含量的变化规律,以及加工和提取条件对提取得率的影响;采用HPLC法测定橄榄苦苷的含量.对油橄榄叶中橄榄苦苷含量研究表明,一年生长期内有两个高峰期,分别是在2月份和5月份,其中2月份最高,两个低谷期则是在11月份和4月份;品种间差别很大,科拉地17.2 %,最低的配多灵仅为1.65 %;20年生较3年生的高.超声波辅助提取法较加热法提取得率高,自然阴干较烘干的提取得率高.     

3个早熟梨品种矿质元素含量变化及其相关性

为了解早熟梨对N、P、K元素的吸收规律,给合理施肥提供指导,以中梨1号、中梨4号和早酥蜜3个新优早熟梨品种为研究对象,研究果实发育期间,果实、叶片和土壤中N、P、K元素含量的变化规律,并对它们之间N、P、K元素含量的相关性进行分析。结果表明,3个早熟梨品种果实、叶片和土壤中N、P、K元素含量的变化规律基本一致;相关性分析结果相似,3个早熟梨品种土壤与果实和叶片中N、P、K元素含量间均无显著相关性。     

氯化锌对库尔勒香梨果实品质的影响

为了提高香梨果实的品质,于不同时期对库尔勒香梨叶片和果实喷施氯化锌溶液.然后测定并分析了果实中相关酶的活性、石细胞大小、密度、含量及部分果实的品质指标.结果表明:喷施氯化锌可使香梨果实石细胞团的直径、密度和含量有不同程度的降低,其中石细胞的含最达到了极显著水平;同时,喷施氯化锌对香梨果实的POD、PPO和PAL活性均有抑制作用,可增加果实的单果质量、果形指数、硬度和可溶性固形物的含量,降低可滴定酸的含量.     

乙醇处理对蒌蒿采后生理生化的影响

研究了不同浓度的外源乙醇(1、2、3和4 mL/kg)对采后蒌蒿生理生化的影响,测定了贮藏过程中的呼吸强度、乙烯释放量、叶绿素含量、粗纤维含量、过氧化物酶(POD)和多酚氧化酶(PPO)的活力与失重率以及感官品质等指标.结果表明:适当浓度(2 mL/kg)的外源乙醇处理可以显著延缓采后蒌蒿的衰老,从而可延长蒌蒿的贮藏寿命.乙醇是一种安全无毒的化学物质,而且乙醇处理操作简单、成本低廉,因此其是一种理想的蒌蒿保鲜剂.     

沙棘不落果原因探讨

沙棘果实成熟与衰老时均不脱落,甚至干缩在果枝上,为了研究沙棘不落果原因,寻求促进落果的有效方法,我们进行了下列实验。一、材料与方法 (一)外施乙烯与ABA于果实完熟前期(9月中下旬)剪取中国沙棘(Hippophaerhamnoides L.Subsp.Sinesis)、西藏沙棘(H.thibetana Schlechtend)带叶果枝,将下端分别浸于装有500、1000ppm乙烯利,50、100ppm ABA与50、100ppm6-康基氨基腺     

果实成熟及其调控技术

果实成熟是一个复杂的过程，伴随着果实成熟，果实本身发生了一系列生理生化变化，给贮存和运输带来不便。因此，本文概述了近年来的储藏保鲜技术和生物工程技术的研究进展，以期为指导果实的贮藏和保鲜提供依据。     

水浴处理板栗MA贮藏期间抗氧化酶活性变化规律

以北京昌平的燕昌板栗为试验材料,研究经不同水浴处理后,板栗MA(Modify atmosphere)贮藏期间抗氧化酶活性的变化规律。结果表明:NaClO水浴处理对板栗内PPO、外PPO活性有抑制作用,除1 000 mg.L-1NaClO处理使板栗外PPO活性一直高于对照外,其余各处理的PPO活性在整个贮藏期间一直低于对照;POD活性的变化规律与PPO活性的变化规律类似,但在贮藏180 d时,NaClO处理的内POD活性高于对照,其中1 000 mg.L-1NaClO处理的内POD活性与对照存在显著差异;100 mg.L-1NaClO和500 mg.L-1NaClO处理使板栗SOD活性升高,而1 000 mg.L-1NaClO处理则使SOD活性降低;NaClO处理板栗提高了板栗的CAT活性,但CAT活性变化趋势与对照相同。     

油橄榄叶中羟基酪醇的含量变化规律研究

以90%甲醇-水溶液为提取剂,用超声波提取不同品种、月份和树龄油橄榄叶中羟基酪醇,采用HPLC方法分析5个品种油橄榄叶中羟基酪醇的含量变化规律,同时考察阿斯、莱星等10种油橄榄叶放置3年后其中橄榄苦苷转化为羟基酪醇的趋势.结果表明:油橄榄叶中羟基酪醇含量一年生长期内有1个高峰期和1个低谷期,5～6月份的含量最高;11～...     

不同种类吸附剂对新鲜板栗仁的保鲜研究

研究在低温条件下（4-10℃）,不同种类的吸附剂对真空包装的板栗仁保鲜效果。通过测定贮藏过程中呼吸强度、水分含量、色度、硬度、淀粉含量以及多酚氧化酶（PPO）和过氧化物酶（POD）活性的变化情况表明：3号吸附剂保鲜效果最佳,与空白相比可推迟25d左右发生胀袋,颜色保持良好,延缓水分散失、硬度下降,对多酚氧化酶（PPO）和过氧化物酶（POD）活性显著抑制,贮藏30d时淀粉含量比对照高0.076g/g。     

Carbohydrate metabolism of vegetative and reproductive sinks in the late-maturing peach cultivar 'Encore'

Activities of NAD(+)-dependent sorbitol dehydrogenase (SDH), sorbitol oxidase (SOX), sucrose synthase (SS), acid invertase (AI), and neutral invertase (NI) in 'Encore' peach (Prunus persica L.) fruits and developing shoot tips were assayed during the growing season to determine whether carbohydrate metabolizing enzymes could serve as indicators of sink strength. In fruit flesh, SS activity was detected during Stage I of growth, when cells were actively dividing, and SDH activity was detected during Stage III, when cells were actively enlarging. Acid invertase activity was detected during Stage I and showed a closer correlation with relative increase in fruit weight during the growing season than SS activity. During seed filling and pit hardening (Stage II), when relative fruit growth rate was slowest, activities of carbohydrate metabolizing enzymes in fruit flesh were not detectable. No SOX activity was detected during Stages I and II. The highest sucrose content occurred near the end of fruit development when the activities of sucrose metabolizing enzymes were low. In developing shoot tips, the sorbitol:sucrose ratio was 2:1 (w/w) and SDH activity was low at the beginning and end of the season when vegetative growth was slowest. The sorbitol:sucrose ratio changed to 1:1 (w/w) along with an increase in SDH activity in shoot tips during the mid-growing season. In 'Nemaguard' peach, SDH exhibited higher activity in root tips than in other organs. Among the sorbitol- and sucrose-metabolizing enzyme activities, only SDH activity was positively correlated with shoot growth in 'Nemaguard' plants.     

冷害桃果实品质劣变及其控制措施

概述了在贮藏期间,桃果实受到冷害后其色泽、质地和风味等品质劣变机理及控制冷害的措施。桃果实的低温褐变主要是酶促褐变,但对不同的品种来说,决定褐变的主导因子则不尽相同。在产生絮败的果实中,果胶物质发生了代谢异常,不溶性果胶明显增加,果胶质代谢异常与PE和PG的活性变化密切相关。桃果实的糖分主要是蔗糖,当冷害出现时桃果实中蔗糖含量迅速下降,可滴定酸含量在贮藏期间也显著下降。目前已从桃果实中分离到近百种芳香成分,冷害桃果实的重要表现之一是原有桃香气变淡或丧失,甚至产生异味。品种与采收成熟度、采前或采后的化学处理、低温锻炼、热调处理和气调均能够不同程度地减轻桃果实的冷害。     

欧李叶表皮形态气孔指标与叶果矿质元素含量变化的关系

欧李(Cerasus humilis)是我国特有的一种野生果树资源,其果实中钙、铁等元素尤为丰富(曹琴等,1999),同时具有抗旱、耐寒、耐贫瘠、耐盐碱等特性,是生态建设和防风固沙的良好树种(姜英淑等,2009;李学强等,2009).研究表明:叶片是植物进化过程中对环境变化敏感且可塑性较大的器官,叶表皮形态结构随着环境的变化而形成自身相对稳定的遗传特征,叶片的气孔、表皮毛、角质层等结构与植物的抗逆性密切相关(李芳兰等,2005;李正理,1981;Bosabalidis et al.,2002;Sam et al.,2000;Mendes et al.,2001),而叶片气孔形态指标大小变化影响着植物的蒸腾、光合、呼吸等作用(潘瑞炽,2008).     

库-源关系对枣树14C-光合产物分配的影响

运用^14C示踪技术对赞皇大枣果实发育期库—源比例和相对位置对^14C—光合产物在不同器官中的分配进行了研究。结果表明：果实缓慢生长期间，与单果枣吊相比，双果枣吊果实的放射比活性下降，但是果实获得的^14C—光合产物量增加了6．68％；枣吊去叶处理(均匀去掉一半叶片)后，剩余叶片的光合产物输出率增加了17．06％，果实获得的标记光合产物增加了15．26％；当果实一侧叶片去除时，其异侧叶片也能提供一定量的光合产物供果实生长发育所需；并且，同一枣股不同枣吊之间也存在着光合产物的相互交换。本文从营养学角度对枣树低坐果率的原因进行了探讨。     

盐度及胁迫时间对红海榄幼苗保护酶活性的影响

以红树植物红海榄(Rhizophora stylosa)幼苗为材料,研究了盐度及胁迫时间对其根、茎、叶中保护酶超氧化物歧化酶(SOD)、过氧化物酶(POD)及多酚氧化酶(PPO)活性的影响。结果表明:不同胁迫时间下,随盐度升高,茎中的SOD活性变化小,根和叶片的SOD活性呈先上升后下降再回升趋势;根、茎、叶的POD活性呈先上升后下降趋势;PPO活性在叶片中呈先下降后上升,根、茎中先上升后下降趋势。在100 mmol.L-1、200 mmol.L-1、300 mmol.L-1盐度下,分别由SOD、PPO、POD起主导作用减少活性氧积累。不同盐度下,胁迫30~60 d时,SOD、POD活性达到最大值,PPO活性也迅速上升。120 d时,在100 mmol.L-1和500 mmol.L-1盐度下SOD活性维持较高水平;在低盐度下PPO活性达峰值,500 mmol.L-1高盐度下PPO活性回升,表明红海榄幼苗要60 d适应基质盐分,在长时间盐胁迫下产生更大的适应性。     

Biological activity of Schinus molle on Triatoma infestans

Hexanic extracts from leaves and fruits of Schinus molle were tested for repellent and insecticidal properties against first instar nymphs and eggs of Triatoma infestans, the vector of Chagas' disease. Leaf and fruit extracts were highly repellent for first nymphs. Fruit extracts had also ovicidal activity.     

山药多酚氧化酶部分特性的研究

采用分光光度法测定波长410nm处山药多酚氧化酶（PPO）的活性,研究了pH、温度、底物浓度、vmax和Km值以及抑制剂对山药PPO活性的影响．结果表明。山药PPO的最适pH=6．0,最适温度为35℃,底物浓度低于0．06moL·L^-1时。山药PPO活性与底物浓度呈线性关系,其Km=0．078moL·L^-1,Vmax=0．259（△OD·min^-1）,抑制剂柠檬酸、苹果酸、L-抗坏血酸对山药PPO活性均有抑制作用．     

Harvest date affects colour and soluble solids concentrations (SSC) of <Emphasis Type="Italic">Uapaca kirkiana</Emphasis> (Muell. Arg.) fruits from natural woodlands

Uapaca kirkiana (Muell. Arg.) is a woodland fruit tree that is native to parts of eastern, central and southern Africa. Unripe fruits are harvested from wild and semi-wild sources by dislodging them from trees. Ripe fruits are gathered from the ground after abscission. Utilization of the fruits is affected by problems such as variability of fruit quality and high perishability. Quality attributes of fruits harvested on 1 and 17 November, and 3 December 2003 and kept at 25–30°C, have been evaluated. On the second and third harvests, fruits were also stored in polythene bags to investigate a common incubation method to hasten ripening. Fruit weight and colour before and after ripening, and the soluble solids concentrations (SSC) of ripe fruits were measured. The redness (a*) values at harvest increased from 3.5 to 5.3 units from 1 November to 3 December. Over this period there was a significant decline in both lightness (L*; 63.8 to 58.9 units) and yellowness (b*, 39.6 to 36.4 units). Skin colour became darker during storage as reflected by the decreasing lightness (L* values from 63.8 to 44.5 units), yellowness (b* values from 36.6 to 20.1 units) and increasing redness (a* values from 3.5 to 8.8 units). Fruits harvested on 17 November and 3 December did not darken during storage as much as fruits harvested on 1 November. Fruits harvested on 3 December lost less weight (13.7%) during storage than those harvested on 1 November (34.0%), while the respective SSC measured 6 days after harvest were 18.1% and 9.9%. Fruits kept in polythene bags had 5.3% lower SSC than those kept on plates. The results demonstrate the benefits of delaying fruit harvest to improve quality attributes such as fruit skin colour at harvest and during storage, to reduce weight loss and to obtain higher SSC during storage.     

Effects of fruit thinning on ascorbate–glutathione cycle metabolism in black currants (<Emphasis Type="Italic">Ribes nigrum</Emphasis> L.)

To elucidate mechanisms regulating ascorbic acid (AsA) biosynthesis and accumulation in the fruit and leaves of black currants, AsA and the activities of key enzymes in the ascorbate–glutathione (AsA–GSH) cycle were measured from fruit set to fruit ripening during fruit thinning treatments of three common commercial black currant cultivars that differed in their AsA levels: ‘Risager’ (low), ‘Brodtrop’ (medium) and ‘Adelinia’ (high). Treatments were 50% fruit reduction (50% of total fruit set) by hand, control was no thinning. Fruit thinning treatment significantly increased AsA content in fruit of all three cultivars from weeks 2 to 8, significantly decreased AsA content in leaves from weeks 3 to 8. Dehydroascorbate reductase and monodehydroascorbate reductase activities in fruit and leaves had a similar pattern, increasing during week 2, rose until they peaked in week 4. Ascorbate peroxidase activity in fruit in the thinning treatment was slightly lower than in the control. Fruit thinning was shown to be a good model to test AsA biosynthesis regulation and accumulation in black currants. The results from our study provided strong evidence that AsA–GSH cycle involved in AsA synthesis and accumulation in fruit.     

叶面肥对油茶幼苗生长和生理特征影响的研究

以1a生出圃的油茶幼苗为材料研究不同浓度无机盐配比的叶面肥对油茶幼苗生长发育的影响,以便获得有利于油茶幼苗生长的叶面肥.在N、P、K肥的基础上,对硼酸、硫酸锌、钼酸钠进行L9(34)正交试验设计来配制叶面肥,喷施油茶幼苗叶片一段时间后测定幼苗的生长及其生理生化指标,对测定结果进行了极差分析和方差分析,并对优化的叶面肥进...