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1.
为探讨黑老虎(Kadsura coccinea )作为果用食物的营养价值,对采自云南省不同产地的野生黑老虎果实分别测定其果皮和果肉中的维生素 C、可溶性固形物、氨基酸、粗纤维、蛋白质、总糖等含量,并进行比较分析。结果表明:野生黑老虎果实含有丰富的人体必需的氨基酸,4个种源中,以勐海的黑老虎果肉中各人体必需氨基酸总含量最高,为0.256%,其次是屏边种源,为0.106%,景东种源为0.0943%,普文种源氨基酸总含量最少,为0.0274%。黑老虎果实还含丰富的维生素 C、粗纤维、蛋白质、总糖等。不同产地之间或单株之间各营养指标变化范围大,变异系数较高,优良种源或优良单株可选择性较强。果肉的养分灰关联度以勐海种源和第2单株最高,将作为备选优良种源和优良单株。  相似文献   

2.
The use of synthetic antioxidants has been associated with serious concerns for human and environmental health. During ripening stages, tomato fruit is exposed to different abiotic stresses which not only influence its nutritional, mechanical, and functional properties at harvest, but also affect the quality and shelf life of the fruit during storage. This study investigated the pattern of changes in dietary antioxidants during various ripening stages of tomato fruit (cv. Red Rose) and their impact on storage behavior of the fruit during cold storage. Tomato fruits were harvested at mature green, breaker, turning, pink, light-red and red stages of maturity. Then, they were analysed for flesh firmness, soluble solids content, titratable acidity, total sugars, pH, dry matter content, lipophilic (lycopene, β-carotene, and total carotenoids), and hydrophilic (ascorbic acid, phenolic and flavonoids) antioxidants. Additional fruits were harvested at each maturity stage and divided into three equal lots, then were subjected to low-temperature (10 ± 1 °C) storage with 80 ± 5% RH, for 7, 14, and 21 days. Flesh firmness, and the levels of dietary antioxidants were analysed following the subsequent storage periods. The results revealed that the peak of hydrophilic antioxidants such as ascorbic acid, phenolic compounds, and flavonoids was between the ‘pink’ and the ‘light-red’ stages of fruit maturity. Whereas tomatoes harvested at the ‘red’ stage of maturity had the highest levels of lycopene and β-carotene. Both the stage of fruit maturity at harvest and duration of cold storage influenced flesh firmness, organoleptic and functional properties of ‘Red Rose’ tomato fruit. In conclusion, the results of the current investigation have practical implications in formulating foods with improved functional properties at processing industries.  相似文献   

3.
Pectin methylesterase (PME, EC 3.1.11) demethoxylates pectins and is believed to be involved in degradation of pectic cell wall components by polygalacturonase in ripening tomato fruit. We have introduced antisense and sense chimeric PME genes into tomato to elucidate the role of PME in fruit development and ripening. Fruits from transgenic plants expressing high levels of antisense PME RNA showed <10% of wild-type PME enzyme activity and undetectable levels of PME protein and mRNA. Lower PME enzyme activity in fruits from transgenic plants was associated with an increased molecular weight and methylesterification of pectins and decreased levels of total and chelator soluble polyuronides in cell walls. The fruits of transgenic plants also contained higher levels of soluble solids than wild-type fruits. This trait was maintained in subsequent generations and segregated in normal Mendelian fashion with the antisense PME gene. These results indicate that reduction in PME enzyme activity in ripening tomato fruits had a marked influence on fruit pectin metabolism and increased the soluble solids content of fruits, but did not interfere with the ripening process.  相似文献   

4.
PSX is a combination of biocontrol bacteria that can potentially prevent and control soil-borne diseases for a variety of crop cultivars. In this study, we investigated the utility of PSX in controlling root-knot nematodes in tomato under field conditions. The application of PSX reduced the severity of disease caused from Meloidogyne incognita by 63–69% and increased tomato yield by 31.5–39%. Furthermore, to investigate the effect of PSX treatment on tomato fruit quality, we quantified the soluble sugar, titratable acid, soluble solids, and vitamin C contents in fruit postharvest. We demonstrated that PSX treatment improved tomato fruit quality. Finally, we also showed that the total nitrogen (N), available N, potassium, and organic matter contents in the soil increased after PSX treatment. PSX is a promising biocontrol preparation that can provide beneficial effects to tomato growers, including biological control of root-knot disease, plant growth promotion, enhanced tomato fruit quality, and increased levels of organic fertilisers in the soil.  相似文献   

5.
The combined stress of high temperature and high relative air humidity is one of the most serious agrometeorological disasters that restricts the production capacity of protected agriculture. However, there is little information about the precise interaction between them on tomato fruit quality. The objectives of this study were to explore the effects of the combined stress of high temperature and relative humidity on the sugar and acid metabolism and fruit quality of tomato fruits, and to determine the best relative air humidity for fruit quality under high temperature environments. Four temperature treatments (32°C, 35°C, 38°C, 41°C), three relative air humidity (50%, 70%, 90%) and four duration (3, 6, 9, 12 d) orthogonal experiments were conducted, with 28°C, 50% as control. The results showed that under high temperature and relative air humidity, the activity of sucrose metabolizing enzymes in young tomato fruits changed, which reduced fruits soluble sugar content; in addition, enzyme activities involved phosphopyruvate carboxylase (PEPC), mitochondria aconitase (MDH) and citrate synthetase (CS) increased which increased the content of organic acids (especially malic acid). Eventually, vitamin C, total sugar and sugar-acid ratio decreased significantly, while the titratable acid increased, resulting in a decrease in fruit flavor quality and nutritional quality in ripe fruit. Specifically, a temperature of 32°C and a relative air humidity of 70% were the best cultivation conditions for tomato reproductive growth period under high temperature. Our results indicating that fruit quality reduced under high temperature at the flowering stage, while increasing the relative air humidity to 70% could alleviate this negative effect. Our results are benefit to better understand the interaction between microclimate parameters under specific climatic conditions in the greenhouse environment and their impact on tomato flavor quality.  相似文献   

6.
Phenolic acids are components of the plant defence system; however few studies had been done with fruits. The objective of this experiment was to elucidate the changes in phenolic acid content in tomato fruits in response to pathogenic attack. Tomato fruit ‘Pinto’ was inoculated with spores of Alternaria alternata and stored for 10 days at 25°C and 90–92% of relative humidity. Sampling of epicarp and mesocarp tissues of control and infected tomato fruits were done every 2 days. Phenolic acids were extracted from each tissue and identified by HPLC coupled to a mass spectrometer. Quantification was done based in standard curves. In vitro evaluation of the phenolic acid effect either one‐by‐one and in a mixture of phenolic acids (MPA) over A. alternata spore germination was done with 25, 50, 100, 200 and 500 mm . It was found caffeic, chlorogenic and vanillic acids in both epicarp and mesocarp tomato tissues before the beginning of the experiment. Infected tomato fruits showed significantly higher concentrations of vanillic acid in the epicarp, only. Chlorogenic acid and the MPA inhibit spore germination by 30%, whereas caffeic acid and vanillic acid inhibit 16% at 500 mm . It was concluded that chlorogenic, vanillic and caffeic acids are phytoanticipins in tomato fruit. The concentration of vanillic acid also increases in tomato fruit epicarp as part of the defence system during a pathogenic attack.  相似文献   

7.
Five different doses of ultraviolet-B (UV-B)radiation were supplied to tomato (Lycopersicon esculeutum.in the winter plastic greenhouse.The influences on the seedling growth,fruit quality and yield of tomato were investigated.Results showed that the seedling growth,and the contents of UV absorbing compounds,soluble sugar,organic acid,vitamin C and lycopene of tomato fruits,and yield of tomato increased under doubled CO2 concentration.Under the doubled CO2 concentration the effects of lost doses of UV-B radiation could further promote the effects of doubled CO:concentration.However,there is no significant increase in yield of tomato.The best dose of UV-B radiation is about 1.163 kJ.m-2.When the dose of UV-B radiation is more than it,the effects of UV-B will be reduced.  相似文献   

8.
Authors have been transfered antisense polygalacturonase (PG, E, C, 3, 2, 1, 15) gene into two tomato cultivars (Lycopersicon esculentum cv. “Lichun” and “Qingfeng”) by Agrobacterium-mediated transformation and obtained homozygotes with expression of antisense PG gene. Analysis of Northern blot and PG activity showed that antisense PG gene had stably expressed in T0~T2 generations of transgenic tomatoes, and this expression could be inherited and enhanced in the progeny. For example, PG activity of To, T1 and T2 generation fruits in line T2-19 of"Lichun” was dropped to 27%, 20% and 4% respectively. But the remarkable decrement of PG activity did not have obvious inhibitory effect on normal fruit softening. The transgenic plants of T0~T2 generations grew and developed normally. Average yield per plant and average weight per fruit in these transgenic plants were a little more than those in nontransgenic control. The content determination of vitamin C, soluble sugar and soluble solid substances indicated that transgenic fruits kept the original texture and taste. The contents of vitamin C and soluble solid substances of “Lichun” T2-19 and soluble sugar of “Qingfeng” T2-46 were higher than those of the control. Stored in 28~32℃ for 30 days, all of nontransgenic fruits and about 50% of the transgenic ones were infected by pathologcal bacteria, a few of remainders could be perserved for 50 days. These evidences suggested that the resistance of the transgenic fruits to pathological bacteria during preservation has been strengthened. The approach which the authors used to study regulation of tomato fruit ripening will be desirable to improve the storability of certain famous and precious fruits.  相似文献   

9.
This review critically evaluated literature on proximate composition and nutritional value of Marula in comparison with other tropical and indigenous fruits in order to identify areas for future research. It was found that nutrients content and processing methods of Marula fruit varied greatly from study to study and according to place of origin, soil, climate, handling, analytical methods used and time that lapsed after harvesting before analysis took place. Marula fruit pulp is reported to have vitamin C content higher than that of most fruits, ranging from 62 mg/100 g to over 400 mg/100 g. Additionally, Marula fruit is reported to have an antioxidant capacity of between 8 and 25 mM, (ascorbic acid equivalents) and a total phenolic content ranging from 7.5 to 24 mg/g dry weight gallic acid equivalent. Marula kernels are also a good source of protein, oil, magnesium, phosphorus and potassium and their oil is used in food preparations. Marula fruits could play a vital role in terms of nutrition to rural community who rely on the usage of the fruits, as they do not have easy access to other sources of nutrients. Recommendation given for future research includes improving Marula fruits juice extraction and yields, investigating the effect of processing and storage on the retention of nutrients such as vitamin C and its antioxidant capacity in processed and unprocessed Marula products and further identifying Marula fruits flavor compounds and their effect on processing and storage.  相似文献   

10.
番茄果实糖酸类物质的含量及比例直接影响其风味品质,前期研究表明,适宜浓度的外源5-氨基乙酰丙酸(ALA)能够促进果实的成熟并提高其芳香品质。该试验为探究外源ALA对番茄果实发育及其糖酸品质的影响,以番茄‘原味1号’(Solanum lycopersicum cv.Yuanwei No.1)品种为试材,于第4穗果授粉后10 d果实表面喷施0、100和200 mg·L^(-1)的ALA溶液,分析ALA对番茄果实形态、果皮色泽及果实不同部位组织中糖、酸类物质组分及含量的影响。结果表明:(1)外源ALA溶液能显著促进番茄果实横径、纵径的增加,提高果实单果重,还显著降低果实硬度,促进果实软化,提升果实口感,并提高了果实V_(C)和可溶性固形物含量。(2)果实不同部位组织(包括果肉、小柱和隔膜)糖类物质组分含量测定结果显示,外源ALA处理能够显著提高果实可溶性总糖含量(包括果糖、葡萄糖和蔗糖),并有利于糖类物质向果肉中积累。(3)在有机酸类物质中,除酒石酸含量增加外,外源ALA处理均能不同程度地降低果实各部位组织中酸类物质含量,从而显著提高番茄果实果肉部位糖酸比,提升果实糖酸品质。研究发现,在番茄果实发育过程中外源施用200 mg·L^(-1) ALA不仅能够促进果实发育及着色,提高单果重,提升果实的外观品质,还有利于果实糖酸品质的形成。  相似文献   

11.
This study was conducted to analyze the bioactive compounds and in vitro antioxidant capacity of tea infusions prepared from whole and ground medicinal fruits, including gardenia, jujube, magnolia, quince, and wolfberries. The dried medicinal fruit samples were ground, and then passed through a 60‐mesh sieve (pore size, 250 μm). Hot water (80 °C) infusions of whole and ground fruits were examined. In average of both whole and ground tea infusions, the maximum bioactive compounds were found in gardenia (β‐carotene, lycopene, and vitamin C), magnolia (total chlorophyll and anthocyanin), quince (flavonoid), and wolfberries (phenolic), and the maximum antioxidant capacity was found in quince (ABTS and DPPH) and wolfberries (NSA). Whole fruit tea infusions showed a higher brightness than the ground fruit tea infusions. The total chlorophyll, anthocyanin, β‐carotene, lycopene, phenolic, flavonoid, and vitamin C contents were found to be significantly (p≤0.001) higher in the ground fruit tea infusions than in the whole fruit tea infusions; additionally, the ground fruit tea infusions had a higher antioxidant capacity especially ABTS, DPPH and NSA. Therefore, the ground fruit tea infusions appeared to be more powerful with regard to the contents of bioactive compounds and antioxidant capacities than the whole fruit tea infusions.  相似文献   

12.
田世平 《植物学报》2000,17(2):160-167
本文主要探讨甜橙[(Citrus sinensis (L.) Osb.]果实在短期超低氧贮藏条件下,果皮和果汁中乙醇和乙醛等挥发性物质的含量,以及它们在不同贮藏温度和货架存放期间的变化和对果实风味品质的影响。在普通冷藏条件下,随着贮藏期的延长,甜橙果实中挥发性物质的含量虽呈上升趋势,但超低氧贮藏更明显地刺激果实中乙醇和乙醛含量的迅速增加。甜橙果实在0.3% O2的超低氧条件下贮藏30 d,果皮中乙醇的含量为519.8 μg/kg,果汁中达1547.1 μg/kg,比普通冷藏的果实高83倍,乙醛的含量较对照果实高6~7倍。低氧处理对果实可溶性固形物,可滴定酸和pH值的影响不大。甜橙果汁中乙醇含量在1000 μg/kg以下时果实的风味品质仍在正常范围之内。结果表明对甜橙果实进行短期(<20 d)的超低氧处理是可行的。  相似文献   

13.
Soil hydraulic principles suggest that post-infiltration hypoxic conditions would be induced in the plant root-zone for drip-irrigated tomato production in small pots filled with natural soil. No previous study specifically examined the response of tomato plants (Solanum lycopersicum) at different growth stages to low soil aeration under these conditions. A 2 × 6 factorial experiment was conducted to quantify effects of no post-infiltration soil aeration versus aeration during 5 different periods (namely 27–33, 34–57, 58–85, 86–99, and 27–99 days after sowing), on growth and fruit quality of potted single tomato plants that were sub-surface trickle-irrigated every 2 days at 2 levels. Soil was aerated by injecting 2.5 liters of air into each pot through the drip tubing immediately after irrigation. Results showed that post-infiltration aeration, especially during the fruit setting (34–57 DAS) and enlargement (58–85 DAS) growth stages, can positively influence the yield, root dry weight and activity, and the nutritional (soluble solids and vitamin C content), taste (titratable acidity), and market quality (shape and firmness) of the tomato fruits. Interactions between irrigation level and post-infiltration aeration on some of these fruit quality parameters indicated a need for further study on the dynamic interplay of air and water in the root zone of the plants under the conditions of this experiment.  相似文献   

14.
果袋颜色对番茄果实微环境及产量和品质的影响   总被引:2,自引:0,他引:2  
王磊  高方胜  徐坤  徐宁 《应用生态学报》2013,24(8):2229-2234
为确定果袋颜色的生态学和生物学效应,以JYK番茄为试材,采用不同颜色果袋进行套袋处理,以不套袋为对照,研究了不同颜色果袋内微环境的变化及其对果实生长发育、产量和品质的影响.结果表明:不同颜色果袋均具有降低光强、提高温度、增加湿度的作用,并均可促进番茄果实膨大,增加单果质量,促进果实提早成熟.其中,以黑色果袋增温促长效果最好,其果实成熟期较对照提早10 d,单果质量增加27.2%;无色、蓝色及红色果袋处理的果实成熟期分别较对照提早8、3和2 d,单果质量分别增加11.8%、6.4%和4.8%.此外,套袋还可促进果实着色,显著提高番茄红素含量,但所有处理的果实硬度及可溶性固形物、可溶性糖、可溶性蛋白含量均低于对照.表明番茄套袋虽增加了产量,但降低了其营养品质.  相似文献   

15.
采用内含子切接点引物 (Intron-splice junction primer) 和长随机引物的PCR (Polymerase chain reaction, 聚合酶链) 标记技术, 就黄土高原不同水肥处理对日光温室番茄土壤微生物群落多样性进行了研究, 并对产量、品质的影响进行了分析。结果表明, 所用的6个引物共能扩增出182条稳定清晰的条带, 其中142条为多态性条带, 多态性条带为78.02%。聚类分析与主坐标分析表明, 水肥对土壤微生物群落多样性的变化有不同的影响。土壤微生物群落多样性指数与番茄产量、果实的Vc、可溶性蛋白质含量成正相关, 尤其与Vc的相关系数达0.9211, 而与可溶性固形物含量成负相关关系。6个水肥组合中WmFh (中水高肥) 土壤微生物群落多样性指数最高, 且番茄果实的Vc、可溶性蛋白质含量及产量显著高于其他处理, 可溶性固形物含量较低。该组合有利于土壤微生物群落的多样性和稳定性的提高, 利于土壤生态环境的改善和番茄优良品质的形成。  相似文献   

16.
Organic products are derived from the organic production system, following organic agricultural cultivation standards, and processing schedules must be identified by an independent certificate authority. The main characteristic of the organic agricultural production system is that all artificial synthetic materials such as pesticides, fertilizers, growth regulators, feed additives, and gene engineering products are not allowed to use. However, there is much debate on organic production quality and health safety issues in academic circles. Some people believe that there is a “Three Cannot” problem with organic production, that is, organic products “cannot be distinguished, cannot be tasted and cannot be measured” compared to common ones. To objectively reflect the differences in nutritional quality and food safety between organic and conventional products, we combined extensive literatures with our research data and have reported some advances in the sensory quality, nutritional value, and safety of the two types of products. The results showed that organic products tasted better; the percentage of leanness was higher, and the products tasted much tender. The dry matter content of most organic crops was about 7–20% higher than that of conventional foods, and enriched vitamin C, anthocyanins, isoflavones, carotenoids, and other phenolic compounds and more elements such as P, Fe, and Mg and trace elements such as Zn, Cu, and Cr were verified in organic crops. Organic animal products contain more beneficial polyunsaturated fatty acids; the nitrate content in organic fruits and vegetables was 20–50% of that in normal fruits. No pesticide residues and less heavy metals were found in the organic products. Our investigation showed that there were obvious differences in quality and safety between the products that originated from organic agriculture systems and conventional alternatives. This conclusion can provide an important theoretical basis for the healthy development of the organic industry.  相似文献   

17.
为确定果袋颜色的生态学和生物学效应,以JYK番茄为试材,采用不同颜色果袋进行套袋处理,以不套袋为对照,研究了不同颜色果袋内微环境的变化及其对果实生长发育、产量和品质的影响.结果表明:不同颜色果袋均具有降低光强、提高温度、增加湿度的作用,并均可促进番茄果实膨大,增加单果质量,促进果实提早成熟.其中,以黑色果袋增温促长效果最好,其果实成熟期较对照提早10 d,单果质量增加27.2%;无色、蓝色及红色果袋处理的果实成熟期分别较对照提早8、3和2 d,单果质量分别增加11.8%、6.4%和4.8%.此外,套袋还可促进果实着色,显著提高番茄红素含量,但所有处理的果实硬度及可溶性固形物、可溶性糖、可溶性蛋白含量均低于对照.表明番茄套袋虽增加了产量,但降低了其营养品质.  相似文献   

18.
Based on high economic importance and nutritious value of tomato fruits and as previous studies employed E8 promoter in fruit ripening-specific gene expression, we have developed transgenic tomato plants overexpressing tomato anionic peroxidase cDNA (tap1) under E8 promoter. Stable transgene integration was confirmed by polymerase chain reaction (PCR) and Southern analysis for nptII. Northern blotting confirmed elevated tap1 levels in the breaker- and red-ripe stages of T(1) transgenic fruits, whereas wild-type (WT) plants did not show tap1 expression in these developmental stages. Further, tap1 expression levels were significantly enhanced in response to wounding in breaker- and red-ripe stages of transgenic fruits, whereas wound-induced expression of tap1 was not detected in WT fruits. Confocal microscopy revealed high accumulation of phenolic compounds at the wound site in transgenic fruits suggesting a role of tap1 in wound-induced phenolic polymerization. Total peroxidase activity has increased remarkably in transgenic pericarp tissues in response to wounding, while very less or minimal levels were recorded in WT pericarp tissues. Transgenic fruits also displayed reduced post-harvest decay and increased resistance toward Alternaria alternata and Fusarium solani infection with noticeable inhibition in lesion formation. Conidiospore germination and mycelial growth of F. solani were severely inhibited when treated with E8-tap1 fruit extracts compared to WT fruits. 3-(4,5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay showed reduced spore viability when incubated in E8-tap1 fruit extracts. Thus, fruit-specific expression of tap1 using E8 promoter is associated with enhanced total peroxidase activity and high phenolic accumulation in fruits with minimized post-harvest deterioration caused by wounding and fungal attack in tomato fruits.  相似文献   

19.
施蚯蚓粪对日光温室土壤及番茄产量与品质的影响   总被引:1,自引:0,他引:1  
设施蔬菜化肥过量施用造成土壤劣化、土传病虫害发生严重,从而导致蔬菜产量和品质下降。蚯蚓粪在改善土壤环境和促进蔬菜生长、提高产量和品质方面具有良好的效果。本试验在日光温室采用等量撒施和沟施两种方式研究了增施蚯蚓粪对土壤养分、酶活性、微生物数量及番茄生长、产量和品质的影响。结果表明: 与不施蚯蚓粪的对照相比,撒施蚯蚓粪和沟施蚯蚓粪处理均改善了土壤环境,显著增加了土壤有机质和氮、磷、钾等养分含量;显著提高了蔗糖酶和过氧化氢酶活性,增加了土壤中细菌、放线菌数量,降低了真菌数量。沟施蚯蚓粪处理明显促进了植株地上部的生长,撒施效果不显著。蚯蚓粪处理明显增强了植株根系活力,提高了叶片的光合作用和叶绿素含量,促进了植株氮和钾含量的积累。撒施和沟施蚯蚓粪处理的番茄产量比对照分别提高了22.7%和32.6%。沟施处理果实中可溶性蛋白、可溶性糖、维生素C和可滴定酸含量分别提高了66.1%、11.0%、122.6%和29.9%,硝酸盐含量降低了65.7%,而撒施处理对番茄果实品质提升效果不明显。  相似文献   

20.
Experiments were conducted on tomato to study the potential of brown alga Sargassum johnstonii as a biofertilizer. Seaweed extract was applied as a foliar spray, soil drench, and soil drench + foliar spray to assess its effect on plant growth, yield, and concentration of lycopene and vitamin C. The main objective of the study was to enhance the biochemical constituents with neutraceutical and antioxidant values in tomato fruit. Different concentrations (0.1%, 0.4%, 0.8%, 2%, 6%, 8%, and 10%; v/v) of seaweed extract were used and growth was observed over a period of 7 months. A total of 14 sprays/drenches were applied at 15-day intervals during the entire vegetative and reproductive phase. A statistically significant increase in vegetative growth (plant height, shoot length, root length, and number of branches), reproductive parameters (flower number, fruit number, and fresh weight), and biochemical constituents (photosynthetic pigments, proteins, total soluble sugars, reducing sugars, starch, phenols, lycopene, and vitamin C) was recorded following all three methods of treatment at higher concentrations of seaweed extract. The study also reports auxin- and cytokinin-like activity, and the presence of macro- (Ca, Mg, Na, and K) and micronutrients (Fe, Cu, Zn, and Mn), in seaweed extract of S. johnstonii, which makes it a potential biofertilizer.  相似文献   

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