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V. Vorne K. Ojanper L. De Temmerman M. Bindi P. Hgy M. B. Jones T. Lawson K. Persson 《European Journal of Agronomy》2002,17(4):369-381
Potato (Solanum tuberosum L cv. Bintje) was exposed to ambient and elevated carbon dioxide (CO2), to ambient and elevated ozone (O3) and to elevated levels of both gases during two growing seasons, 1998 and 1999. Experiments in open-top chambers (OTC) were carried out in Finland, Sweden, Ireland, United Kingdom, Germany and Belgium and a FACE (Free Air Carbon dioxide Enrichment) experiment was carried out in Italy. In OTCs the plants were grown under ambient CO2 concentrations or with 550 and 680 μl l−1 CO2 alone or in combination with ambient or elevated O3 concentrations (target seasonal mean of 60 nl l−1 8 h per day). In the FACE systems the plants were exposed to ambient or 550 μl l−1 CO2. In the OTC experiments the reducing sugar content of potato tubers decreased significantly with increased concentration of O3. The starch content of potato tubers decreased, with negative impact on tuber quality, but the ascorbic acid concentration increased as a function of the AOT40 (The sum of the differences between hourly ozone concentration and 40 nl l−1 for each hour when the concentration exceeds 40 nl l−1 during a relevant growing season). However, simultaneous exposure to elevated CO2 counteracted the ozone effect. With increase in the CO2 exposure, glycoalkaloid and nitrate concentrations decreased yielding improved quality, while the citric acid concentration decreased causing a higher risk for discoloration after cooking. The amount of dry matter and starch increased significantly in the FACE experiment. 相似文献
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A simple and rapid method for the determination of naturally occurring, potentially hazardous glycoalkaloids (GAs) in potatoes
and their products has been developed. The procedure is based on the on-line solid-phase extraction of the acetic acid extracts
from potato products and combined with liquid chromatography (LC)-mass spectrometry (MS) in a fully automated system (Symbiosis™,
Spark Holland Instruments, Emmen, The Netherlands). As sorbent material HySphere™ 18HD was used for alkaloid enrichment. GAs
were eluted with the LC gradient and directly analysed by MS. Detection of the analytes was achieved in the sensitive multiple
reaction monitoring mode using two characteristic ions (m/z 98 as a qualifier for GAs and m/z 868.3 as a quantifier for α-solanine or m/z 852.4 for α-chaconine). Typical validation data for method precision (v
k α-solanine = 5.3–6.5, v
k α-chaconine = 3.4–15.4), accuracy (average recovery of α-solanine = 84%, average recovery of α-chaconine = 87%) and linearity
over the range from 1 to 1,000 ng ml−1 (R
2 = 0.9915 for α-solanine, R
2 = 0.9939 for α-chaconine) with detection limits of 0.3 ng ml−1 for α-chaconine and 0.5 ng ml−1 for α-solanine were obtained. GA contents of commercial potato products were determined by the new on-line method and afterwards
compared with those obtained with an established high-performance LC routine procedure. Better performance of the on-line
procedure was obvious from the standard deviations of both methods. Other advantages included a strong reduction of overall
analysis time, human intervention and solvent consumption as well as waste production. The time required for the on-line analysis
was 5 min, which would allow processing of almost 100 samples in 8 h. 相似文献
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Gavin Ramsay D. Wynne Griffiths Nigel Deighton 《Genetic Resources and Crop Evolution》2005,51(8):805-813
Patterns of variation for the solanidine-based glycoalkaloids have been determined for tuber material of genebank accessions of landraces of the cultivated potato and three closely-related wild species. Total levels were low in the cultivated taxa investigated,S. phureja, S. stenotomum, and the tetraploidS. tuberosum in its two formsS. tuberosum ssp.tuberosum andS. tuberosum ssp.andigena. The only solanidine-based glycolkaloids found in the tubers investigated in this study were-solanine and-chaconine, with one additional related compound, dehydrocommersonine, found in tubers of an accession ofS. canasense. The ratio of chaconine : solanine differed markedly from a mean of 0.98 inS. phureja to 2.28 in ChileanS. tuberosum ssp.tuberosum. The chaconine : solanine ratio was relatively constant within these two taxa, reflecting their relatively narrow genetic bases, but was much more variable within the taxa regarded as ancestral,S. stenotomum andS. tuberosum ssp.andigena. The wild speciesS. sparsipilum has been implicated in the origin of the tetraploid potato,S. tuberosum, but there was no support for this from the patterns of variation in chaconine : solanine ratio. The cline of chaconine : solanine ratios in cultivated potatoes along the spine of S. America does not appear to relate to the influence of local wild species through introgression, but may instead reflect differing selective pressures acting in different parts of the native range of the cultivated potato. 相似文献
4.
[目的]优选马铃薯中糖苷生物碱的提取方法和条件。[方法]以新鲜的马铃薯皮为样品,采用乙酸提取-氨水沉淀、超声波辅助酸水提取-氨水沉淀、甲醇提取-氨水沉淀、双溶剂法提取、多溶剂混合提取、酸醇提取-氨水沉淀及乙酸和亚硫酸钠提取-氨水沉淀7种方法对马铃薯中的糖苷生物碱进行提取,通过单因素试验考察提取温度、超声时间、酸浓度对提取效果的影响,优化马铃薯中糖苷生物碱的提取方法与条件。[结果]7种提取方法中,以超声波辅助酸水提取-氨水沉淀法的提取效果最好;最佳提取条件为温度30℃,超声时间20 min,酸度25%。[结论]不用有机溶剂而直接加一定浓度的酸并辅助以超声波振荡的提取方法具有操作简单、提取周期短、提取效果较好的特点。 相似文献
5.
Anthocyanins gain more and more importance as natural colourants. Besides many other plant species, coloured potatoes could
serve as a potential source. Therefore, 27 potato cultivars and four breeding clones of different origin were analysed for
their anthocyanin contents in fresh weight (fw). On average the highest amounts of anthocyanins were found in the skin (0.65 g kg−1 fw) of potatoes. The corresponding values of samples taken from whole tubers (0.31 kg−1 fw) and flesh (0.22 kg−1 fw) were significantly lower (p<0.03). The analysis revealed considerable differences in the amounts of anthocyanins between the 31 cultivars/breeding clones.
Among them ȁ8Peru Purpleȁ9 revealed the highest anthocyanin content in the skin with 2.96 g kg−1 fw. A similar high value was reached by ȁ8Violettfleischigeȁ9 and clone 1.81.202–92 N. Also for the other two types of samples,
flesh and whole tubers, these three genotypes exhibited the highest level of anthocyanins. Interestingly, different rates
of nitrogen fertilization at 100 and 200 kg ha−1 had no significant effect on the pigment content of potatoes. The same was observed with respect to the year or the location
of plant growth. There were also no significant changes in the anthocyanin contents of tubers during storage for 135 days.
In dry matter, starch and protein contents the coloured potato cultivars/breeding clones were comparable with traditional
cultivars. Further tests have shown that the glycoalkaloids were mainly localized in the skin of coloured potatoes. 相似文献
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