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1.
It was previously revealed that esculeoside A, a new glycoalkaloid, and esculeogenin A, a new aglycon of esculeoside A, contained in ripe tomato ameliorate atherosclerosis in apoE-deficent mice. This study examined whether tomatidine, the aglycone of tomatine, which is a major tomato glycoalkaloid, also shows similar inhibitory effects on cholesterol ester (CE) accumulation in human monocyte-derived macrophages (HMDM) and atherogenesis in apoE-deficient mice. Tomatidine significantly inhibited the CE accumulation induced by acetylated LDL in HMDM in a dose-dependent manner. Tomatidine also inhibited CE formation in Chinese hamster ovary cells overexpressing acyl-CoA:cholesterol acyl-transferase (ACAT)-1 or ACAT-2, suggesting that tomatidine suppresses both ACAT-1 and ACAT-2 activities. Furthermore, the oral administration of tomatidine to apoE-deficient mice significantly reduced levels of serum cholesterol, LDL-cholesterol, and areas of atherosclerotic lesions. The study provides the first evidence that tomatidine significantly suppresses the activity of ACAT and leads to reduction of atherogenesis.  相似文献   

2.
Tomato plants (Lycopersicon esculentum) synthesize the glycoalkaloids dehydrotomatine and alpha-tomatine, possibly as a defense against bacteria, fungi, viruses, and insects. We used a high-performance liquid chromatography method with UV detection at 208 nm for the analysis of these compounds in various tissues. An Inertsil ODS-2 column with a mobile phase of acetonitrile/20 mM KH2PO4 (24/76, v/v) afforded good separation of the two glycoalkaloids in mini-tomato extracts, fruit harvested at different stages of maturity, and calyxes, flowers, leaves, roots, and stems. The two peaks appeared at approximately 17 and approximately 21 min. Recoveries from tomato fruit extracts spiked with dehydrotomatine and alpha-tomatine were 87.7 +/- 6.8 and 89.8 +/- 3.4% (n = 5), respectively. The detection limit is estimated to be 0.39 microg for dehydrotomatine and 0.94 microg for alpha-tomatine. The dehydrotomatine and alpha-tomatine content of tomatoes varied from 42 to 1498 and 521 to 16 285 microg/g of fresh weight, respectively. The ratio of alpha-tomatine to dehydrotomatine ranged from 10.9 to 12.5 in tomatoes and from 2.3 to 7.8 in the other plant tissues. These results suggest that the biosynthesis of the glycoalkaloids is under separate genetic control in each plant part. Degradation of both glycoalkaloids occurred at approximately the same rate during maturation of the tomatoes on the vine. An Inertsil NH2 column, with acetonitrile/1 mM KH2PO4 (96/4, v/v) as the eluent, enabled the fractionation of commercial tomatidine into tomatidenol and tomatidine, the aglycons of dehydrotomatine and alpha-tomatine, respectively. The information should be useful for evaluating tomatoes and vegetative tissues for dehydrotomatine/alpha-tomatine content during fruit development and their respective roles in host-plant resistance and the diet.  相似文献   

3.
The effect of moderate intensity pulsed electric fields (MIPEF) on the bioactive compounds (total polyphenol, lycopene, and vitamin C content) as well as on the antioxidant capacity of tomato fruit was studied. The MIPEF treatment conditions were optimized to obtain tomato fruit with a high content of bioactive compounds. Tomato fruits were subjected to different electric field strengths (from 0.4 to 2.0 kV/cm) and number of pulses (from 5 to 30) and then immediately refrigerated at 4 °C for 24 h. A concentration of bioactive compounds higher than that of untreated tomatoes was obtained in MIPEF-treated tomatoes. A 44% increase in total polyphenol content was achieved under 30 pulses at 1.2 kV/cm. The hydrophilic antioxidant capacity was also enhanced by 44% applying 18 pulses at 1.2 kV/cm, and the lipophilic antioxidant capacity was increased by 37% under 5 pulses at 1.2 kV/cm. The maximum overall level of bioactive compounds and antioxidant capacity in the treated tomatoes was obtained under 16 pulses at 1 kV/cm. Therefore, MIPEF treatments could be considered an effective method to enhance the bioactive compound content and antioxidant potential of tomatoes.  相似文献   

4.
Occurrence of flavonols in tomatoes and tomato-based products   总被引:9,自引:0,他引:9  
The flavonol contents of 20 varieties of tomato fruit were investigated in relation to variety, size, season, and country of origin. Ten commonly consumed tomato-based food products were also assessed. Free and conjugated flavonols were identified and quantified using reversed-phase HPLC. Ninety-eight percent of flavonols detected in tomatoes were found to occur in the skin. Tomatoes contained, primarily as conjugates, quercetin and kaempferol. The main quercetin conjugate was identified as rutin (quercetin 3-rhamnosylglucoside) by LC-MS. The total flavonol content of the different varieties of tomato that were analyzed varied from 1.3 to 22.2 microgram/g of fresh weight (fw). Smaller cherry tomato fruits originating from warm sunny climates, such as Spain and Israel, were found to contain the highest concentration of flavonols. Among the tomato-based products investigated, tomato juice and tomato purée were rich in flavonols, containing 14-16 microgram/mL and 70 microgram/g fw, respectively. In contrast to fresh tomatoes, most tomato-based products contained significant amounts of free flavonols.  相似文献   

5.
王慧俐  郑晓冬 《核农学报》2022,36(2):466-472
为探讨内生真菌印度梨形孢(Piriformospora indica)对樱桃番茄(Lycopersicon esculentum Mill.)产量、品质及采后抗性的影响,本研究以杭杂5号樱桃番茄幼苗为试验材料,于温室大棚盆栽条件下在植株根部接种印度梨形孢,待果实成熟时测定果实的产量、自然腐烂率、对病原菌的抗性及贮藏期的...  相似文献   

6.
This study was conducted to investigate the antioxidant vitamin C, the polyphenol content, and the hydrophilic antioxidant capacity of tomato juice, baked tomatoes, tomato sauce, and tomato soup. During the production of tomato juice and during the preparation of the other tomato products, samples were taken after different times, respectively, after each particular production step. High-performance liquid chromatography was used to determine the content of vitamin C. The total phenolics content was analyzed spectrophotometrically by using the Folin-Ciocalteu method. The hydrophilic antioxidant capacity was measured by using three different methods: the Trolox equivalent antioxidant capacity assay, the ferric reducing antioxidant power test, and the photochemiluminescence assay. The vitamin C contents of the tomato products decreased during the thermal processing of tomatoes. In contrast, the total phenolics concentration and the water soluble antioxidant capacity increased.  相似文献   

7.
Processed fruits and vegetables have been long considered to have lower nutritional value than their fresh commodities due to the loss of vitamin C during processing. This research group found vitamin C in apples contributed < 0.4% of total antioxidant activity, indicating most of the activity comes from the natural combination of phytochemicals. This suggests that processed fruits and vegetables may retain their antioxidant activity despite the loss of vitamin C. Here it is shown that thermal processing elevated total antioxidant activity and bioaccessible lycopene content in tomatoes and produced no significant changes in the total phenolics and total flavonoids content, although loss of vitamin C was observed. The raw tomato had 0.76 +/- 0.03 micromol of vitamin C/g of tomato. After 2, 15, and 30 min of heating at 88 degrees C, the vitamin C content significantly dropped to 0.68 +/- 0.02, 0.64 +/- 0.01, and 0.54 +/- 0.02 micromol of vitamin C/g of tomato, respectively (p < 0.01). The raw tomato had 2.01 +/- 0.04 mg of trans-lycopene/g of tomato. After 2, 15, and 30 min of heating at 88 degrees C, the trans-lycopene content had increased to 3.11+/- 0.04, 5.45 +/- 0.02, and 5.32 +/- 0.05 mg of trans-lycopene/g of tomato (p < 0.01). The antioxidant activity of raw tomatoes was 4.13 +/- 0.36 micromol of vitamin C equiv/g of tomato. With heat treatment at 88 degrees C for 2, 15, and 30 min, the total antioxidant activity significantly increased to 5.29 +/- 0.26, 5.53 +/- 0.24, and 6.70 +/- 0.25 micromol of vitamin C equiv/g of tomato, respectively (p < 0.01). There were no significant changes in either total phenolics or total flavonoids. These findings indicate thermal processing enhanced the nutritional value of tomatoes by increasing the bioaccessible lycopene content and total antioxidant activity and are against the notion that processed fruits and vegetables have lower nutritional value than fresh produce. This information may have a significant impact on consumers' food selection by increasing their consumption of fruits and vegetables to reduce the risks of chronic diseases.  相似文献   

8.
The aim of the present study was to determine the effect of animal-based organic nutrition and environmental parameters on tomato fruit quality, as well as to establish relations among colour and morphological values performed by the Tomato Analyzer (TA) software application. Organic tomato fruits produced by three organic nutrient solutions, which consisted of different mixtures of several OMRI certified nitrogen fertilizers and one inorganic nutrient solution (Steiner’s solution) as the control, were evaluated for their polyphenol and carotenoid content. We used Tomato Analyzer (TA) to evaluate fruit size and shape. Moreover, we implemented a digital image analysis tool, Color Test (CT), as part of the TA software application to collect and analyse fruit colour parameters. The application of organic fertilizers positively affected the total hydrolysable and condensed polyphenols of tomato fruits compared to the control. The high air temperature (>30°C) and sub-optimal light intensity negatively affected the carotene content of tomato fruits, as well as their morphological and colour attributes. Plants fed with organic solutions containing ASA + ASB + NK2SO4 showed comparable morphology and fruit colour attributes to those of the control plants that received Steiner’s nutrient solution. The results indicated that the application of organic fertilizers positively affected the total hydrolysable and condensed polyphenols of tomato fruits compared to the control. Plants fed with the Steiner’s nutrient solution exhibited the highest carotenoid content in tomato fruits. Organically produced tomatoes through animal-based fertilizer application displayed similar fruit morphology and colour attributes compared to conventionally produced tomatoes.  相似文献   

9.
One nonanthocyanin-accumulating (Ailsa Craig) and three anthocyanin-accumulating tomato genotypes (Anthocyanin fruit type, Atroviolaceum, and Sun Black) were analyzed to assess differences in their carotenoid and anthocyanin levels and color and to evaluate the effects of nutrient solutions with different salt concentrations on these parameters. The carotenoid content of control Atroviolaceum tomatoes was ca. 2-2.5-fold higher relative to the other two types, and the color of its puree could be visually distinguished from those of other genotypes. Salinity stress led in some cases to a 2-3-fold increase in the lycopene content. Saline treatment increased the accumulation of total anthocyanins in fruits of Sun Black (2-fold increase), while it reduced it in fruits of Anthocyanin (10-fold decrease). In general, the treatment increased the differences in color of different purees. These results indicate that salinity stress can lead to similar or higher increases in tomato carotenoids than those achieved by genetic engineering. In addition, these changes were accompanied by visually discernible color differences in tomato products. Our findings show the considerable potential of exploiting saline soils to obtain tomatoes with higher levels of secondary metabolites like carotenoids and anthocyanins.  相似文献   

10.
Resveratrol is a stilbene phytoalexin well-known for its presence in grape, wine, and peanut. As a result of its antioxidant and chemopreventative properties, it has gained much attention as a functional food ingredient. A gas chromatography-mass spectrometry method for the detection of resveratrol, its 3-glucopyranoside piceid, and the cis isomers of both compounds has been developed and used to quantitate the levels of these compounds in the skin of commercially available tomato fruit (Lycopersicon esculentum Mill.). The resveratrol concentration remains relatively stable during fruit maturation, reaching a maximum concentration in the skin of 18.4 +/- 1.6 microg/g dry weight at 4 weeks postbreaker. No stilbenes were detected in the flesh of tomato fruit.  相似文献   

11.
The change in the carotenoid and bioantioxidant content of tomato as a function of varietal and technological factors was investigated in the present work. No great differences were found between cultivars for fresh consumption (salad tomatoes) and those for processing in ascorbic acid content. The concentration of ascorbic acid ranged between 14.6 and 21.7 mg/100 g fresh weight of ripe tomato fruit. Processing cultivars contained higher amounts of tocopherols, particularly alpha-tocopherol than tomatoes for fresh consumption. Significant differences could be obtained between the examined varieties with regard to carotenoid concentration. The different tomatoes varied not only in the total carotenoid content but also in the qualitative distribution of some pigments such as lycopene, beta-carotene and lutein. During heat-based processing, ascorbic acid, tocopherols, and carotenoids showed different role and response. Ascorbic acid, alpha-tocopherol quinone, and beta-carotene were the most susceptible components toward thermal degradation.  相似文献   

12.
LED红蓝弱光照射保持樱桃番茄冷库贮藏品质   总被引:5,自引:4,他引:1  
为了探究单色光对番茄冷藏过程中品质的影响,开发樱桃番茄保鲜新技术,以绿熟期樱桃番茄(Lycopersicon esculentum Mill.)为试材,在4℃条件下分别采用发光二极管(LED,light emitting diode)红蓝单色弱光(30 lx)持续照射,研究LED红蓝单色弱光对樱桃番茄采后贮藏过程中感官和主要营养品质指标的影响。结果表明:研制的LED试验装置稳定可靠,红蓝单色光的发射光谱稳定,不因光照强度的变化而发生偏移。贮藏10 d以后LED红蓝光处理的樱桃番茄感官品质显著优于无光对照(P0.05),且LED红光处理好于蓝光处理(P0.05)。LED蓝光照射能较好地保持樱桃番茄维生素C含量(P0.05),但LED红光照射不利于维生素C含量的保持。LED红蓝单色弱光照射有利于促进樱桃番茄早期贮藏过程中的还原糖和可溶性总糖积累,显著抑制贮藏后期糖含量的下降(P0.05)。LED红蓝单色弱光照射处理还能显著延缓樱桃番茄贮藏过程中可溶性固形物下降(P0.05),提高樱桃番茄果实可滴定酸的含量,其中LED红光处理显著高于蓝光处理(P0.05)。贮藏20 d时,红光照射可显著促进番茄红素的合成,但贮藏过程中LED蓝光照射与对照差异不显著(P0.05)。综合来看,与对照(CK)相比,LED红蓝弱光(30 lx)照射有利于樱桃番茄4℃贮藏过程中感官和营养价值的保持,其中LED红色弱光照射处理效果较好。作为一种简便可行的物理保鲜方法,LED红蓝弱光持续照射处理在樱桃番茄采后营养品质调控方面具有应用潜力。  相似文献   

13.
The aim of this study was to investigate the effect of different types of tomato processing on contents of lycopene, beta-carotene, and alpha-tocopherol. Samples of tomato sauce, tomato soup, baked tomato slices, and tomato juice were taken at different times of heating, respectively, after each step of production. HPLC was used to analyze contents of carotenoids and vitamin E. Due to the loss of water during thermal processing, contents of lycopene, beta-carotene, and alpha-tocopherol on a wet weight basis increased. On a dry weight basis, contents of lycopene increased or decreased depending on the origin of the tomatoes used, whereas the beta-carotene contents decreased or were quite stable. In contrast to lycopene, beta-carotene isomerized due to thermal processing. The alpha-tocopherol contents significantly rose during short-term heating. The increase was not caused by release of alpha-tocopherol from the seeds containing predominantly gamma-tocopherol and accounting for 2% of total alpha-tocopherol content only.  相似文献   

14.
Processing effects on lycopene content and antioxidant activity of tomatoes   总被引:8,自引:0,他引:8  
Consumption of tomato products has been associated with decreased risk of some cancer types, and the tomato antioxidant, lycopene, is thought to play an important role in the observed health effects. In this study, four carotenoids, trans-lycopene, phytofluene, phytoene, and zeta-carotene, were quantified in tomato products. Samples of raw tomatoes, tomato juice after hot break scalder, and final paste were obtained from two different processing plants over two years. Comparison of carotenoid levels throughout processing indicated that lycopene losses during processing of tomatoes into final paste (25-30 degrees Brix) ranged from 9 to 28%. The initial Brix level of the raw tomatoes appeared to influence the amount of lycopene loss that occurred, possibly due to the differences in processing time required to achieve the final desired Brix level of the paste. In general, no consistent changes in the other carotenoids were observed as a function of processing. The antioxidant activity of fresh tomatoes, tomato paste, and three fractions obtained from these products (i.e., aqueous, methanol, and hexane fractions) was also determined. In both a free radical quenching assay and a singlet oxygen quenching assay, significant antioxidant activity was found in both the hexane fraction (containing lycopene) and the methanol fraction, which contained the phenolic antioxidants caffeic and chlorogenic acid. The results suggest that in addition to lycopene, polyphenols in tomatoes may also be important in conferring protective antioxidative effects.  相似文献   

15.
The tomato fresh fruit market has rigorous quality standards that can be challenging to meet, particularly under highly variable climatic conditions. Information is required about the influence of nutritional regime on tomato fruit and the interaction of potassium (K) and boron (B) in particular. A field experiment was conducted in 2002 and 2003 to evaluate the effects of K and B on yield and quality of fresh market tomatoes cv. ‘Mountain Spring’ at a southwest Michigan site with well‐drained soil (Alfisol Hapludalf, Oakville fine sand). Treatments applied during fruit development included three fertigation regimes (1N:0.8K, 1N:1.7K, and 1N:2.5K) in the presence and absence of a weekly foliar spray of B (300 mg?L?1 B). Increasing K concentration in the fertilizer increased K content in leaf tissue, but in some cases reduced tissue calcium (Ca) and B. Fruit quality was influenced by nutrition, as the greatest rate of K was associated with increased crack susceptibility as indicated by a fruit bioassay and a 14% increase in incidence of the defect “shoulder check” in field‐grown fruit compared to less rates of K nutrition. Boron foliar spray increased tomato marketable yield and fruit quality, reducing shoulder check incidence by 50% compared to zero‐B‐treated plants in 2003. Because of yield and quality improvements, B was a cost‐effective treatment as shown by partial budget analysis, whereas increasing K nutrition did not provide consistent economic benefits. Moderate K rates were associated with the greatest marketable yield, and the 1N:1.7K plus foliar B nutrient regime produced the greatest quality fruit. Overall data were consistent with the need to carefully evaluate K and B nutrition in tomatoes, in the context of soil type, yield potential, fruit quality, and nutrition regime.  相似文献   

16.
不同施肥水平对日光温室番茄生长发育的影响   总被引:5,自引:0,他引:5  
根据目前设施蔬菜生产中的施肥状况设计了不施肥(CK)、只施有机肥(SOF)、理论施肥(TF)、习惯施肥(CF)和超量施肥(OF) 5个施肥水平,研究不同施肥水平对日光温室番茄生长发育的影响,结果表明随着施肥水平的提高,番茄的株高、茎粗、叶片数、叶面积都逐渐增加;但对番茄比叶面积、叶面积比、平均节间距和单果重却没有明显的影响.番茄第一花序花数和生物学产量依次为不施肥<只施有机肥<理论施肥<经验施肥<超量施肥,其中理论施肥和超量施肥的经济系数较高.随着施肥量的增加,番茄果实中抗坏血酸、有机酸、游离氨基酸、硝酸盐含量增加,可溶性糖含量减小,糖酸比降低,果实的风味变差.目前温室生产中大量施用氮肥可以暂时提高番茄产量,但有悖于设施蔬菜土壤可持续利用.  相似文献   

17.
番茄专用基质缓释肥料研制及其生物学效应   总被引:1,自引:2,他引:1  
应用不同的胶粘剂制备了三种基质缓释肥料,通过缓释效果和安全性评价,筛选出基质缓释肥料2作为番茄专用基质缓释肥料。研究了番茄专用基质缓释肥料的生物学效应,结果表明:番茄专用基质缓释肥料提高了各个生育时期尤其是结果后期番茄植株的根系活力;增加了后期产量所占比例,极显著地提高了果实产量;既提高了果实糖/酸比和维生素C含量,又降低了果实硝态氮含量;同时,大幅度提高了氮素的利用率。  相似文献   

18.
为了实现番茄可溶性固形物含量(soluble solids content,SSC)的有效检测,提出高光谱漫透射成像检测方法,对比该成像方式下不同姿态(果脐端面姿态BS、赤道圆周3姿态C1、C2、C3以及组合姿态C1C2C3)的检测效果。首先对采集的不同姿态光谱图像,通过剪裁消除图像边缘噪声。针对圆周赤道面姿态C1、C2和C3,进行了拼接处理,获得组合姿态图像 C1C2C3。其后对以上5种姿态图像进行单波段背景分割,获取目标区域,并统计不同姿态下番茄漫透射平均光谱。最后利用漫透射光谱结合偏最小二乘回归(partial least squares,PLS)方法,对番茄SSC分别在450~720、720~990、450~990 nm 3个波段进行定量分析。结果表明,组合姿态C1C2C3在3个波段区域上整体检测效果优于单个姿态的检测效果,其模型验证集均方根误差(root mean squared error of prediction,RMSEP)分别为0.299%、0.133%、0.151%;相关系数rp分别为0.42,0.89,0.90。说明利用高光谱漫透射成像,获取组合姿态光谱图像,可以有效检测番茄SSC。  相似文献   

19.
为了探究局部按压对白熟期、转色期、粉红期番茄机械损伤的影响规律,该研究采用水果硬度计对番茄进行按压,并用扫描电镜观察按压处番茄组织微观结构变化,以腐烂、褶皱、有压痕、无压痕4个损伤等级和损伤显象天数作为评价标准,通过按压试验,分析局部按压压强对各级损伤的影响规律,得到不同成熟度番茄各损伤等级的压强分布区间,建立番茄局部机械损伤评估分类模型。最后,通过三指电爪进行了抓取试验。结果表明:1)各成熟度番茄的损伤程度随按压压强和成熟度升高而增大;2)各成熟度番茄的显象天数随成熟度升高而减小,腐烂天数与按压压强相关性很小,褶皱天数随按压压强升高而减小;3)以中位数作为代表压强,一级损伤代表压强按成熟度由低到高依次为:366、355、337 kPa,比二级损伤代表压强265,245,225 kPa均提高了30%左右;出现三级损伤的代表压强按成熟度由低到高依次为:165,115,90 kPa;腐烂天数范围为3~7d,相较于褶皱天数范围7~17d提前了50%左右,抓取试验结果与评估分类模型吻合度均大于等于95%,验证了损伤评估分类模型的正确性。研究结果可为番茄多指采摘机械手的设计与开发提供参考。  相似文献   

20.
  【目的】  研究外源喷施不同浓度猪血蛋白水解物 (PP)对樱桃番茄植株生长和品质的影响,以期为高产优质樱桃番茄生产提供理论参考。  【方法】  以樱桃番茄品种“盆栽红”为试验材料,采用基质栽培,设置3个PP浓度:0 g/L (CK)、1 g/L (PP1)、2 g/L (PP2),在开花期进行叶面喷施,整个生育期共喷施6次。樱桃番茄在第三穗果实完全成熟后收获,分析外源PP对樱桃番茄植株生长、光合作用、养分吸收以及果实品质的影响。  【结果】  PP1和PP2处理不同程度地增加了番茄地上部、根部以及果实中氮、磷、钾含量,显著提高了叶片叶绿素含量、净光合速率 (Pn)、蒸腾速率 (Tr)和气孔导度 (Gs),植株地上部鲜重比CK处理分别增加了18.2%和40.6%,干重分别增加了42.3%和57.4%,且PP2处理的效果好于PP1处理。与CK处理相比,PP2处理番茄的产量、单果重、横径、纵径和硬度分别增加了37.4%、26.6%、16.3%、10.3%和30.8%,并有效改善了果实色泽,提高了樱桃番茄的外观品质。PP2处理有利于樱桃番茄果实中可溶性糖、可溶性蛋白、抗坏血酸和谷胱甘肽的积累,较CK分别增加了24.2%、25.5%、96.6%和30.9%;番茄果实中的总酚、类黄酮和花色素苷含量分别增加18.7%、33.3%和56.2%,DPPH自由基清除能力和铁还原抗氧化能力分别增加了27.7%和29.4%,显著提高了番茄果实的抗氧化活性。  【结论】  外源喷施2 g/L的猪血蛋白水解物能有效改善番茄植株的养分吸收和光合作用,促进植株生长和番茄品质的提升,是一种提高樱桃番茄产量、改善营养和功能性品质的高效有机措施。  相似文献   

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