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1.
Carotenoids and tocols of 20 genotypes of colored barley divided into three groups (A, B, C) were investigated. These included 16 F8 recombinant inbred lines obtained from crosses of four parental lines: 2005 FG, K4-31, L94 and Priora. The aim of the present study was to identify, quantify and profile characterize of tocols and carotenoids. Tocols profile is characterized by the prevalence of tocotrienols on tocopherols. The α-tocotrienol was the most represented tocol isomer, contributing about 53.03% of the total content. The highest α-tocotrienol content (33.67 μg g-1) was found in the blue naked parental genotype 3007 (C-Group). The most abundant carotenoid was lutein on average 86% of total followed by zeaxanthin 10% and by α-carotene 3.40%. The Priora cultivar (C-Group) was the genotype with the highest lutein content (4.10 μg g-1). The study found great variability in the content of carotenoids and tocols along the lines of each group.  相似文献   

2.
The presence of arsenic in irrigation water and in paddy field soil were investigated to assess the accumulation of arsenic and its distribution in the various parts (root, straw, husk, and grain) of rice plant from an arsenic effected area of West Bengal. Results showed that the level of arsenic in irrigation water (0.05–0.70 mg l−1) was much above the WHO recommended arsenic limit of 0.01 mg l−1 for drinking water. The paddy soil gets contaminated from the irrigation water and thus enhancing the bioaccumulation of arsenic in rice plants. The total soil arsenic concentrations ranged from 1.34 to 14.09 mg kg−1. Soil organic carbon showed positive correlation with arsenic accumulation in rice plant, while soil pH showed strong negative correlation. Higher accumulation of arsenic was noticed in the root (6.92 ± 0.241–28.63 ± 0.225 mg kg−1) as compared to the straw (1.18 ± 0.002–2.13 ± 0.009 mg kg−1), husk (0.40 ± 0.004–1.05 ± 0.006 mg kg−1), and grain (0.16 ± 0.001–0.58 ± 0.003 mg kg−1) parts of the rice plant. However, the accumulation of arsenic in the rice grain of all the studied samples was found to be between 0.16 ± 0.001 and 0.58 ± 0.003 mg kg−1 dry weights of arsenic, which did not exceed the permissible limit in rice (1.0 mg kg−1 according to WHO recommendation). Two rice plant varieties, one high yielding (Red Minikit) and another local (Megi) had been chosen for the study of arsenic translocation. Higher translocation of arsenic was seen in the high yielding variety (0.194–0.393) compared to that by the local rice variety (0.099–0.161). An appreciable high efficiency in translocation of arsenic from shoot to grain (0.099–0.393) was observed in both the rice varieties compared to the translocation from root to shoot (0.040–0.108).  相似文献   

3.
The aim of this investigation was to study the antioxidant and anticancer activities of young sprouts of some traditional Korean salad plants. Total phenolics, antioxidant and anticancer activities of the methanol extracts from young sprouts of 11 salad plants were determined. The highest amount of phenolics was found in methanol extracts of Euonymus alatus (235.7 mg kg−1), followed by Hypericum ascyron (197.1 mg kg−1), Zanthoxylum piperitum (194.1 mg kg−1) and Zanthoxylum schinifolium (142.5 mg kg−1). Methanol extracts of E. alatus, H. ascyron, and Z. piperitum at 63 mg kg−1 exhibited the highest dose-depend DPPH radical scavenging activity by 91.2, 91.2 and 83.9%, respectively. According to the MTT results, the methanol extracts from Stellaria aquatica, Eleutherococcus sessilifolrus and Z. schinifolium showed the highest anticancer activities against Calu-6 (IC50 < 25.0 μgml−1) and from S. aquatica—the highest anticancer activities against SNU-601 (153.3 μgml−1), following by E. sessilifolrus (196.7 μg ml−1) and Amaranthus mangostanus (303.1 μgml−1). Total phenolics were highly correlated with the DPPH, suggesting that they contribute to the antioxidant properties of the studied plants. In conclusion: young sprouts of Korean salad possess antioxidant and anticancer properties and could be used as a supplement to proper drugs.  相似文献   

4.
Einkorn (Triticum monococcum L., subsp. monococcum), emmer (Triticum dicoccum Schuebl [Schrank], subsp. dicoccum) and spring bread wheat (Triticum aestivum L.) may be rich in lipophilic antioxidants (tocols and carotenoids), and therefore potential food sources with good nutritional properties. The aim of the present study was to determine the contents of major lipophilic antioxidants beneficial for human health in wheat varieties and landraces for breeding and production. In field experiments over two years, fifteen einkorn, emmer and spring wheat varieties were analysed for the contents of tocols and carotenoids in grain. A high carotenoid content (lutein, zeaxanthin, β-carotene) was typical for the selected einkorn genotypes. Among the analysed wheat species, the highest content was of β-tocotrienol, especially in the einkorn accessions. α-Tocotrienol was abundant in einkorn and emmer wheat species. Higher contents of α- and β-tocopherols were characteristic of spring and emmer wheats. δ-Tocotrienol has been detected for the first time in einkorn and some emmer accessions, although in low concentrations. Significant effects of genotype on the contents of carotenoids and tocols were found with einkorn differing from emmer and spring wheats. The year of cultivation had less effect on the contents of carotenoids and tocols. Selected accessions of einkorn with high contents of carotenoids and tocotrienols as well as spring and emmer wheats with higher contents of tocopherols are good sources of antioxidants with potential health promoting benefits for the production of nutritionally enhanced foods.  相似文献   

5.
Summary The glycoalkaloid content in 18 potato varieties grown in Oman was measured by HPLC using peel and flesh tissues. The total glycoalkaloid content of the tubers was found to be variety dependent and varied greatly between the 18 varieties. The total glycoalkaloid in the tubers of seven varieties was within the safe limit of ≤200 mg kg− 1 FW recommended for food safety, whereas the remaining 11 varieties exceeded this upper limit. The principal glycoalkaloids α-chaconine and σ-solanine were present in higher concentration in the peel than in the flesh of all varieties with the former being the principal alkaloid in the peel. The flesh of all of the 18 potato varieties contained total glycoalkaloid levels lower than the upper safety limit. The leaves of the 18 potato varieties were also analyzed for glycoalkaloids. The levels of glycoalkaloids in expanding leaves were higher than that of expanded leaves with the exception of six varieties. The principal glycoalkaloid in expanding and expanded leaves was α-chaconine. No correlation was observed between the glycoalkaloids levels of in the leaves and tubers.  相似文献   

6.
Summary The method of Vadukul (1991) for determining maleic hydrazide (MH) was modified and gave recoveries of free MH of 89%±4%. The values recorded on individual tubers ranged from 2–14 mg kg−1. Maleic hydrazide was evenly distributed throughout the tuber (peel, outer and inner flesh) but concentration increased slightly as tuber size increased. The concentration of free MH decreased from 7 to 3 mg kg−1 over the storage period of 5 1/2 months. Acid hydrolysis released substantial amounts of MH particularly from older potatoes (13 mg kg−1) compared with 6 mg kg−1 from new potatoes, implying that free MH is gradually converted to a bound form with time after treatment. No evidence was found for the presence of a β-glucoside of MH.  相似文献   

7.
The seeds of 15 Polish pea varieties contained from 221 to 281 g/kg crude protein with a mean of 240.2±3.5 g/kg dry matter (DM). The weight of 1000 pea seeds, depending on cultivar, ranged from 209.4 to 280.4 g. No interactive effect between the seed mass and the crude protein content was detected. The highest significant negative correlation between weight of seeds and dietary fiber content wasr=−0.815XX. The content of dietary fiber ranged from 161.5 to 209.9 g/kg with a mean of 187.9±3.8 g/kg. The mean gross energy of seeds was 18.1±0.28 MJ/kg. Amino acid composition of all the cultivars was similar, which was indicated by a similar index of essential amino acids (EAAI) of about 69.7±0.25. Trypsin inhibitor content in seeds was from 2.83 to 7.32 TIU/mg and the content of phytates ranged from 6.32 to 13.36 mg/g DM. The mean content of polyphenols and flavanols in analysed pea cultivars was 0.92 amd 0.46 mg/g, respectively. In the seeds of most cultivars little or no pyrimidine glucosides, i.e. vicine and convicine, were found. The overall mean oligosaccharide content was 64.3±1.8 g/kg, of which α-galactosides were 46.8±2.0 g/kg. The antinutritional factor content was not significantly correlated with protein content. No statistical relationship was found between crude protein and dietary fiber content. It was observed that pea cultivars with higher trypsin inhibitor activity contained significantly less flavanols (r=−0.607X) and α-galactosides (r=−0.617X). The varieties with higher seed content of dietary fiber contained the highest amount of α-galactosides (r=0.514X).  相似文献   

8.
Wild yams make a significant contribution to diets of tribal people in Nepal. However, these wild tubers are unpalatable, taste bitter, produce inflammation and show occasional toxicity. Four wild yam species, which are eaten after primary treatment by Nepali aborigines, were analyzed for bitter and toxic principles. Bitter components were identified as furanoid norditerpenes (diosbulbins A and B). Diosbulbins A and B were found in the range of 0.023–0.046 and 0.151–0.442 g kg−1, respectively. Results demonstrated that diosbulbin B, with an average value of 0.314 g kg−1, was the principal bitter compound as compared to diosbulbin A (0.037 g kg−1). The toxic alkaloid, dioscorine and histamine (an allergen) were not detected in these tubers, whereas cyanogens (as HCN equivalent) content were found ranging from 3.2 to 6.0 ppm. Our results revealed that Nepali wild yam tubers are not toxic varieties, as they do not contain either toxic dioscorine or histamine and cyanogens contents were satisfactorily below the safety limits. The inflammation and occasional toxicity observed could possibly be due to the presence of high level of oxalate in these tubers. Domestic cooking methods were found to be very efficient in removing bitterness, thus making the bitter yams palatable.  相似文献   

9.
The globe artichoke is a widely consumed vegetable in the Mediterranean Basin, with Italy being the leading producer. In southern Italy, its cultivation contributes to local economic stability and social development. The producers are increasingly choosing to replace autochthonous varieties, such as ‘Violetto di Sicilia’, with cultivars bred or selected outside of the region, putting pressure on the maintenance of traditional varieties. Here, we have undertaken a detailed morphological and chemical analysis of a group of clones selected from a population of ‘Violetto di Sicilia’. All the traits measured displayed genetic variation, particularly the total content of phenolics and minerals. The capitula of the ‘Violetto di Sicilia’ clones contained, on average, 6.3 g kg−1 of fresh weight total phenolics, compared with 4.5 g kg−1 in the two commercial varieties. The clones also had more inulin than commercial varieties (254 vs. 225 g kg−1 of dry matter), as well as a good mineral content. The set of clones is of interest in the context of the proposed improvement of the crop through breeding and selection of genotypes with high nutritional quality and a specific end-use (industrial processing or fresh consumption).  相似文献   

10.
Recently, new varieties of hull-less barley have been developed with altered carbohydrate traits. To our knowledge, there is no study on metabolic characteristics in ruminants of the proteins in the newly developed hull-less barley varieties. The objectives of this study were to: compare metabolic characteristics of the proteins of zero-amylose waxy (CDC Fibar), low-amylose waxy (CDC Rattan), high-amylose (HB08302), and normal starch (CDC McGwire) hull-less barley. In situ animal trials were carried out to generate the original rumen fermentation data for modeling nutrient supply to dairy cattle by using two dairy nutrition models – Dutch DVE/OEB system and NRC 2001. The major comparisons were made in terms of i) truly absorbed protein in the small intestine (DVE or MP, and ii) degraded protein balance (DPB). The study revealed that zero-amylose waxy hull-less barley was superior (P < 0.05) in both DVE (123 vs. 117, 114, 103 g kg−1 DM) and MP (112 vs. 93, 96, and 87 g kg−1 DM) when hull-less barley was evaluated as a single feed for dairy cattle. All of four hull-less barley varieties had negative DPB (DPBOEB; −37.4, −17.1, −30.2, and −28.2 g kg−1 DM for normal starch, zero-amylose waxy, waxy, and high-amylose cultivar, respectively), indicating the potential N shortage. In conclusion, the alteration of starch structure in granule provided a relatively balanced energy and protein for microbial synthesis in the rumen. The DVE and DPB predicted by using the DVE/OEB system can be explained (r2 > 0.76) by the equivalent parameters, predicted by using the NRC 2001 model. The alteration of starch structure in granule affects metabolic characteristics of the proteins of hull-less barley in ruminants.  相似文献   

11.
Summary Dimethylnaphthalene (DMN) was shown to be an effective sprout suppressant. In the laboratory and in a commercial seed potato store, a DMN isomer mixture applied at 100 mg kg−1 controlled sprout growth as effectively as tecnazene applied at 135 mg kg−1. When seed tubers, treated at 100 mg kg−1, were aired for 4 to 7 weeks before planting, subsequent emergence and total yield were not adversely affected but treatment at 300 mg kg−1 delayed emergence and reduced yield. Treatment with DMN at 100 mg kg−1 increased the yield of medium sized tubers more than did that by tecnazene at 135 mg kg−1. One initial application of DMN (200 mg kg−1) did not maintain adequate sprout control in a long-term, higher temperature, ventilated store of tubers intended for processing where reapplication or continuous application would be required.
Zusammenfassung Eine Mischung von Dimethylnaphthalin-(DMN)-Isomeren wurde als Keimhemmer eingestuft. Verschiedene Mengen der Mischung wurden auf einem Tonerdetr?ger auf eingelagerte Knollen gebracht und 14 Wochen sp?ter die Keiml?nge gemessen. Die Ergebnisse (siehe Tabelle 1) zeigen, dass die kleinste wirksame Anwendungsrate der Isomermischung 100 mg kg−1 betr?gt. Die Wirkungen des DMN bei 100 mg kg−1 auf das nachfolgende Wachstum der behandelten Pflanzknollen wurden dann mit den Wirkungen von Tecnazen (1,2,4,5-Tetrachlor-3-Nitrobenzol) und mit unbehandelten Kontrollen verglichen. DMN wurde auch mit einer Menge von 300 mg kg−1 angewendet, um die Wirkungen einer unausgeglichenen Anwendung oder einer zuf?lligen Ueberdosis zu vergleichen. Alle 4 Verfahren wurden vor dem Auspflanzen 3 verschiedenen Kombinationen von Behandlungsdauer/Belüftungsdauer unterworfen. Der Einfluss der 4 chemischen Verfahren auf die Keiml?nge am Ende einer 17 Wochen dauernden Behandlungszeit sind in Tabelle 2 aufgeführt. Die Gesamtwirkungen der chemischen Verfahren auf das nachfolgende Auflaufen und die Ernte gehen aus Tabelle 3 hervor. Die Wirkungen der verschiedenen Kombinationen von Behandlungsdauer/Belüftungsdauer für die 4 chemischen Verfahren auf eine Sorte sind in Tabelle 4 dargestellt. Die Auswirkungen von DMN auf die nachfolgende Pflanzgutleistung wurden ebenfalls in einem handelsüblichen Modellversuch untersucht. Dafür wurde Standardpflanzgut unter üblichen landwirtschaftlichen Produktionsbedingungen verwendet. Die Ergebnisse dieses Versuches sind in Tabelle 5 aufgeführt. Diese beiden Untersuchungen zeigen, dass DMN als Keimhemmer an Pflanzkartoffeln ideal geeignet ist. Die behandelten Knollen werden vor dem Auspflanzen 4–7 Wochen bei 10°C belüftet; das nachfolgende Auflaufen und der Gesamtertrag werden nicht ernsthaft beeinflusst. Die Behandlung wird jedoch eine kleine Reduktion im Ertrag von grossen Knollen und eine entsprechende Zunahme im Ertrag von mittleren und kleinen Knollen innerhalb des Gesamtertrages hervorrufen. Das Ausmass dieser Wirkung ist jedoch geringer als dasjenige, das von Tecnazen erzeugt wird. Die keimhemmenden Eigenschaften von DMN wurden auch in einem grossen, belüfteten Speisekartoffellager untersucht. Die Chemikalie wurde in verschiedenen Mengen angewendet und die Knollen w?hrend 27 Wochen bei 7–8°C gelagert. Unter diesen Bedingungen war der Grad der erreichten Keimbek?mpfung (siehe Tabelle 6) unzul?nglich, selbst wenn 200 mg kg−1 DMN verwendet wurden. Unter diesen Bedingungen ware Wiederanwendung oder fortgesetzte Anwendung der Chemilakie notwendig.
Résumé Un mélange d’isomères de dimethylnaphthalène (DMN) a été étudié en tant qu’inhibiteur de germination par application de différentes quantités de ce mélange (support d’alumine) sur tubercules stockés, puis en évaluant la longueur des germes 14 semaines plus tard. Les résultats (voir tableau 1) montrent que la dose efficace minimale du mélange d’isomères est de 100 mg kg−1. Les effets du DMN à 100 mg kg−1 sur la croissance ultérieure des semences traitées sont ensuite comparés aux effets du tecnazène (1,2,4,5-tetrachloro-3-nitrobenzène) et avec des témoins non traités. DMN est aussi appliqué à 300 mg kg−1 pour rechercher les effets d’une application irrégulière ou d’un surdosage accidentel. Les 4 traitements sont soumis à 3 durées de ventilation avant plantation. Les effets des 4 traitements chimiques sur la longueur des germes à la fin de la période de 17 semaines sont indiqués au tableau 2, et les effets du traitement sur la levée et le rendement figurent tableau 3. Les effets des différentes durées de ventilation combinées aux 4 traitements chimiques sur une variété sont indiqués au tableau 4. L’effet du DMN sur le rendement de semences a été également étudié dans une expérimentation à l’échelle commerciale utilisant les standards de la production du plant. Les résultats de ces essais sont indiqués au tableau 5. Ces deux expérimentations montrent que le DMN convient très bien pour inhiber la germination des plants et si les tubercules sont ventilés pendant 4 à 7 semaines à 10°C avant la plantation, la levée et le rendement total ne sont pas sérieusement affectés. Le traitement peut cependant entrainer une petite réduction du rendement en gros calibres et un accroissement correspondant du rendement en moyens et petits tubercules, à l’intérieur du rendement total. Cet effet est cependant moins marqué qu’avec le tecnazène. Les propriétés inhibitrices du DMN sont également étudiées sur pomme de terre de consommation dans un vaste local ventilé. Le produit est appliqué à différentes doses et les tubercules sont stockés pendant 27 semaines à 7–8°C. Dans ces conditions, l’inhibition de la germination obtenue (voir tableau 6) est insuffisant, même quand le DMN est appliqué à 200 mg kg−1. Pour ces conditions, un nouveau traitement, ou une application continue (en nébulisation) serait nécessaire.
  相似文献   

12.
The unsaponifiable lipid fraction of plant-based foods is a potential source of bioactive components such as phytosterols, squalene, and tocopherols. The objective of the present study was to determine the levels of phytosterols, and squalene, as well as tocopherols (α and β + γ) in selected grains, seeds, and legumes. The method comprised acid hydrolysis and lipid extraction followed by alkaline saponification, prior to analysis by HPLC. In addition, the fatty acid profile of the foods was determined via total lipid extraction, fatty acid derivitisation and GC analysis. In general, β-sitosterol was the most prevalent phytosterol, ranging in concentration from 24.9 mg/100 g in pumpkin seed to 191.4 mg/100 g in peas. Squalene identified in all foods examined in this study, was particularly abundant in pumpkin seed (89.0 mg/100 g). The sum of α- and β+ γ-tocopherols ranged from 0.1 mg/100 g in rye to 15.9 mg/100 g in pumpkin seeds. Total oil content ranged from 0.9% (w/w) in butter beans to 42.3% (w/w) in pumpkin seed and the type of fat, in all foods examined, was predominantly unsaturated. In conclusion, seeds, grains, and legumes are a rich natural source of phytosterols. Additionally, they contain noticeable amounts of squalene and tocopherols, and in general, their fatty acid profile is favorable.  相似文献   

13.
Nutrient and antinutritional/toxic factors present in some edible flowers consumed in Mexico were determined. The edible flowers were: Agave salmiana, Aloe vera, Arbutus xalapensis, Cucurbita pepo (cultivated), Erythrina americana, Erythrina caribaea, Euphorbia radians benth and Yucca filifera. The nutrient content in the flowers studied is similar to that of the edible leaves and flowers studied mainly in Africa. The moisture content of the flowers varied from 860 to 932 g kg−1. Crude protein (CP) was between 113 to 275 g kg−1 DM, crude fiber, 104 to 177 g kg−1 DM and the nitrogen free extract, between 425 to 667 g kg−1 DM. The highest chemical score (CS) was found in E. americana and A. salmiana; in five samples the limiting amino acid was lysine, and in three of them it was tryptophan. Trypsin inhibitors and hemaglutinnins had a very low concentration. Alkaloids were present in both the Erythrina species and the saponins in A. salmiana and Y. filifera. Cyanogenic glucosides were not found in the studied flowers. The traditional process of preparing these specific flowers before consumption is by cooking them and discarding the broth; in this way the toxic substances are diminished or eliminated. These edible flowers from wild plants consumed in local areas of the country play an important role in the diet of the people at least during the short time of the season where they are blooming.  相似文献   

14.
Summary In-vitro conservation of microplants at 24±1 °C was investigated in six potato genotypes belonging to different maturity groups. Growth was controlled by using different concentrations of sucrose (20, 40 and 60 g 1−1) alone or in combination with either mannitol (20 and 40 g 1−1) or sorbitol (20 and 40 g 1−1) in Murashige and Skoog medium. Maximum microplant survival (55.5–77.8%) after 12 months of storage was on medium supplemented with 20 g 1−1 sucrose plus 40 g 1−1 sorbitol. Microplants so conserved were in good to very good condition, without phenotypic abnormalities and had enough nodes for sub-culturing. Microplant survival and microplant condition were closely associated with each other but not with root growth. The success of conservation was unaffected by maturity group of the genotypes. This conservation approach at 24±1 °C can be an effective alternative to low temperature (6–8 °C) storage, especially in tropical and sub-tropical conditions, where the ambient temperatures in summer can reach 45–50°C.  相似文献   

15.
The present study was carried out to evaluate nutrient losses that occur during the course of agricultural activity from rice paddy fields of reclaimed tidal flat. For this study, we chose a salt-affected rice paddy field located in the Saemangeum reclaimed tidal area, which is located on the western South Korean coasts. The plot size was 1,000 m2 (40 m × 25 m) with three replicates. The soil belonged to the Gwanghwal series, i.e., it was of the coarse silty, mixed, mesic type of Typic Haplaquents (saline alluvial soil). The input quantities of nitrogen and phosphorus (as chemical fertilizer) into the experimental rice paddy field were 200 kg N ha−1 and 51 kg P2O5 ha−1 per annum, and the respective input quantities of each due to precipitation were 9.3–12.9 kg N ha−1 and 0.4–0.7 kg P ha−1 per annum. In terms of irrigation water, these input quantities were 4.5–8.2 kg N ha−1 and 0.3–0.9 kg P ha−1 per annum, respectively. Losses of these nutrients due to surface runoff were 22.5–38.1 kg N ha−1 and 0.7–2.2 kg P ha−1 for the year 2003, and 26.8–29.6 kg N ha−1 and 1.6–1.9 kg P ha−1 for the year 2004, respectively. Losses of these nutrients due to subsurface infiltration during the irrigation period were 0.44–0.67 kg N ha−1 and 0.03–0.04 kg P ha−1 for the year 2003, and 0.15–0.16 kg N ha−1 and 0.05–0.06 kg P ha−1 for 2004. When losses of nitrogen and phosphorus were compared to the amount of nutrients supplied by chemical fertilizers, it was found that 11.3–19.1% of nitrogen and 0.5–1.7% of phosphorus were lost via surface runoff, whereas subsurface losses accounted to 0.2–0.8% for nitrogen and only 0.02–0.04% for phosphorus during the 2-year study period.  相似文献   

16.
Summary Mass tuberisation was obtained on plantlets growing from nodal potato cuttings cultured in vitro on Murashige-Skoog (MS) medium under continuous light of 5000 lux at 24–25°C. Tuber formation was stimulated by transferring the plantlets to MS or White-Nitsch-Morel (WhNM) liquid or solid media supplemented with 8% sucrose, 2 mg 1−1 benzyladenine (BAP), 2 mg 1−1 naphthalenacetic acid (NAA) and/or 100 mg 1−1 (2-chloroethyl) trimethylammonium chloride (CCC). Liquid media invariably induced heavier minitubers (390–790 mg each). The process to tuberisation took only two months. Minitubers always produced normal growing plants after dormancy break.  相似文献   

17.
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   

18.
The content of tocols is a parameter of increasing interest in evaluating the quality of plant-based food. Cereal grains are amongst the most widely occurring plant food components and their potential for enriching the content of vitamin E and/or hypocholesterolemic active compounds in food is therefore of interest. We investigated the presence of tocol homologues in hulled and hull-less barley, as influenced by genotype and location. Both factors significantly influenced the amount of tocols in the barley kernel, with genotype having the greater effect for most homologues. Significant genotype×location interaction was observed for six out of eight homologues, but not for total tocotrienols and total tocols; however, the coefficient of determination for genotype was high for most homologues, so that selection for this traits should be possible. The hull-less trait negatively affected the content of total tocols, influencing both tocopherols (positively) and tocotrienols (negatively). Statistical analysis suggests this is due to a different sub-set of homologues, which is preferentially accumulated in hull-less vs. hulled barleys. As hulled barley had a greater accumulation of more bioactive homologues, the selection of hull-less barleys for this trait should be considered for enhancing food quality.  相似文献   

19.
Residue concentrations of the sprout suppressant chlorpropham (or CIPC) were determined in raw and cooked potatoes and processed potato products, 48 h after CIPC aerosol treatment and after 30 days of subsequent storage at 4 or 12 °C. In the raw (uncooked) tuber, 48 h after CIPC treatment, the CIPC residue in the peel was 4.7 mg kg-1, while in the peeled tuber it was 0.1 mg kg-1. Boiling resulted in a decrease in residue concentration in the peel, but no significant differences in the residue concentration of the peeled tuber were observed. Pressure cooking resulted in a significantly increased residue concentration in the peel, but no significant change in the peeled tuber, whereas microwave cooking also did not increase the residue concentration in the peel significantly compared with that in raw tubers. Also the trend towards increases in residue concentration in microwave-cooked peeled tubers was not significant. The CIPC residue concentration detected in peeled tubers was 0.4–0.7 mg kg-1 after boiling, 0.4–1.5 mg kg-1 after pressure cooking and 0.4–3.8 mg kg-1 after microwave cooking. The highest values were always found for tubers stored for 30 days at 4 °C. Processed products such as crisps, French fries, dehydrated sliced potatoes and starch contained different concentrations of CIPC residue, which was also detected in the cooking water and frying oil. The highest residue concentrations detected were 0.7, 4.7, 1.3 and 0.2 mg kg-1 in crisps, French fries, dehydrated sliced potatoes and starch, respectively. The highest CIPC residue concentration observed in raw potatoes was much lower than the maximum residue level of 10 mg kg-1 prescribed by the European Union.  相似文献   

20.
Indigenous non-refrigerated methods like heaps and pits are used in India for short-term storage of potatoes (Solanum tuberosum L.) to avoid distress sale. Storing untreated potatoes generally results in high losses from sprouting, moisture loss and rotting. To reduce storage losses by inhibition of sprouting and to determine the suitability of stored potatoes for processing into crisps, a single spray application of a commercial formulation of 3-chlorophenyl carbamate (CIPC or chlorpropham) 50% a.i., (Oorja, United Phosphorus Limited, Mumbai, India) of CIPC (or chlorpropham) was tested on potatoes during storage from March to June under two traditional storage methods [heap (17–33 °C, 58–92% relative humidity (RH)) and pit (17–27 °C, 72–95% RH)] in 2 years [2005 up to 90 days of storage (DOS) and 2006 up to 105 DOS], using four cultivars and two rates of CIPC application (20 and 30 mg a.i. kg−1 tubers). The two rates of application were comparably effective in reducing weight losses, sprouting and sprout growth in stored tubers, and the effect was more pronounced in pit storage than in heap storage. By contrast to untreated tubers, CIPC-treated potatoes remained turgid under the two storage methods and fetched market prices comparable to those for cold-stored (2–4 °C) potatoes after 105 days of storage. Reducing sugar concentrations in treated potatoes decreased during storage especially in 2006 when the initial reducing sugar concentration was higher than in 2005. Crisp colour improved only in 2005 after 90 DOS, but it deteriorated in 2006 during storage up to 105 DOS. Sucrose concentration increased tremendously during storage in 2 years. Only one cultivar (Kufri Chipsona-1) with low initial reducing sugar concentration and less sucrose accumulation during storage could produce acceptable colour crisps after storage in both years. The remaining three cultivars—with high initial reducing sugar concentration—were suitable for processing after storage in heap and pit in 2005, but not in 2006. Stored potatoes were safe for human consumption as the CIPC residue concentrations were far below the permissible level of 10 mg kg−1 as prescribed by the European Union. Single spray application of CIPC (20 mg kg−1 treatment) can effectively reduce storage losses in potatoes stored in traditional non-refrigerated methods of heap and pit and extend the storage life by 90 to 105 days.  相似文献   

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