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1.
The availability of -carotene from Spirulina as compared to standard all trans -carotene was studied by the liver and kidney vitamin A storage method. After 21 days of vitamin A depletion, the rats were repleted with -carotene from Spirulina and a standard source at two dietary levels (60 and 120 µg/day) for a 10 day period. At lower levels, the liver storage levels of vitamin A and the percent of -carotene absorption were comparable to those of the standard. At higher levels both these parameters of the Spirulina fed group were significantly (P<0.01) inferior to the standard source fed group. However, the Spirulina fed group showed better (P<0.05) growth than the standard fed group did at both low and high levels of feeding.  相似文献   

2.
Dried green leafy vegetables constitute a major dietary source of provitamin A carotenoids for people living in semi-arid areas of Tanzania. In the present study, eight vegetable varieties commonly consumed in these areas were either traditionally sun-dried or solar-dried, and the amount of provitamin A carotenoids were determined by HPLC. In the fresh blanched leaves, the contents of -carotene, -carotene, 9-cis--carotene and 13-cis--carotene were in the range of 526–917, 12–39, 80–136 and 16–40 g/g dry matter/basis; dmb, respectively. The average amounts of all-trans--carotene in the leaves after blanching, solar drying and open sun-drying were 662, 502 and 353 g/g dmb, respectively, all significantly different from each other (p <0.001). The average amounts of all-trans--carotene were 21, 15 and 8 g/g dmb (p <0.05) and of 9-cis--carotene 101, 82 and 63 g/g dmb (p <0.05) in the blanched, solar-dried and open sun-dried samples, respectively. Estimation of the amount of retinol equivalents provided by the dried vegetables for preparation of an edible portion of 100 g relish showed that solar-dried vegetables contributed more (between 120–275%) than the recommended level of vitamin A, and on average 43% more retinol equivalents than relishes of open sun-dried vegetables.Thus, it is concluded that the amount of provitamin A-carotenes in traditionally treated vegetables were highly reduced by open sun-drying while solar drying resulted in significantly more retention of the carotenes. All-trans--carotene and 9-cis--carotene were similarly affected as all-trans--carotene by the two drying methods. Consumption of a 100 g portion of solar-dried vegetable relish could provide the recommended daily intake of vitamin A.  相似文献   

3.
Some locally available fruits and vegetables of the arid zone of Rajasthanwere analyzed for their -carotene content; the selected fruits and vegetables were: Dansra (Rhus myserensis), Kachri (Cucumis collosus), fruit Kachri (Cucumis collosus), Kair (Capparisdecidua) and Sanghri (Prosopis cineriria). The -carotene contents of the samples were estimated in fresh and various processed states (blanched, dried and roasted). The results showed the heat lability of -carotene. Among the samples, kair was found to be the richest source of -carotene. Variety, too, had an impact on the content of this fat soluble vitamin.  相似文献   

4.
Provitamin A carotenoids from green leafy vegetables constitute a major dietary source of vitamin A in Tanzania. The efficiency of different vegetable preparations in contributing to the daily safe intake level of vitamin A for children was evaluated in the present study. The amount of bioaccessible (available for absorption) all-trans--carotene from green leafy vegetable dishes prepared either traditionally in households or with an improved method was estimated by an in vitro digestion method that simulates human digestion. The median vegetable portion size consumed by 34 children (2--12 years old) in the surveyed households was determined by weighing. The amount of all-trans--carotene available for absorption from the same type of vegetables cooked without oil by traditional or a modified method ranged from 5 to 12% and 4 to 15%, respectively. Vegetables cooked with modified method with oil had 2–5 times higher amount of in vitro accessible all-trans--carotene than vegetables cooked without oil. A median portion (84 g) of such a relish then provided 88–477% of the daily safe intake level of vitamin A, while portions cooked without oil only provided between 23 and 46%. In this study, a wide variation in all-trans--carotene content and bioaccessibility among studied green leaves was obtained. Still, to supply daily safe intake level of vitamin A for children from a median vegetable relish portion it is necessary to add oil in the preparation.  相似文献   

5.
Male albino rats (Charles Foster, n = 40) were fed a synthetic diet deficient in vitamin A for 4 weeks. Six rats died during the depletion period. Of the 34 surviving, 5 rats were continued on the vitamin A deficient diet for 4 more weeks and 24 were repleted with vitamin A (4000 IU/kg diet) in the form of vitamin A acetate (group A, n = 8), fresh drumstick leaves (group B, n = 8) or dehydrated drumstick leaves (group C, n = 8) for 4 weeks. The remaining 10 rats were continued on the vitamin A adequate diet for 4 (n = 5) and 8 weeks, respectively (n = 5). A marked reduction in food intake, body weight, accompanied by clinical signs of vitamin A deficiency and a decline in serum vitamin A (29.2 to 19.1 g/dL) and liver vitamin A (3.7 to 2.0 g/dL) were seen at the end of 4 weeks of feeding a vitamin A deficient diet. On repletion significant improvements in clinical signs, food intake and body weights were noted in the three groups compared to the baseline (n = 5) and at the end of 4 weeks of depletion. The gain in body weight was highest for the group repleted with dehydrated drumstick leaves. Among the repleted groups, the serum vitamin A was highest for group A (34.7 g/dL) given synthetic vitamin A, compared to group B (25.8 g/dL) and group C (28.2 g/dL) given drumstick leaves. All these were significantly higher than the serum vitamin A values seen at the end of 4 weeks of depletion (19.1 g/dL). A significant improvement was also observed in the liver retinol levels on repletion for 4 weeks in the three groups, compared to the vitamin A depleted rats. These results imply that -carotene from drumstick leaves was effective in overcoming vitamin A deficiency although serum vitamin A levels remained somewhat lower compared to the group repleted with vitamin A acetate. In terms of growth parameters, the fresh and dehydrated drumstick leaves were better than the synthetic vitamin A. It is therefore concluded that in the developing countries like India, sources of vitamin A such as drumstick leaves are valuable in overcoming the problem of vitamin A deficiency.  相似文献   

6.
Twenty four school children of 7–9 years of age were divided into two groups of six boys and six girls each. One group was given a daily supplement of Suji halwa, a sweet snack made with semolina and red palm oil, supplying 2400 µg of -carotene and the second group was the control group which was given 600 µg of oral vitamin A palmitate, for 60 days. Vitamin A status before and after supplementation was assessed by the Modified Relative Dose Response Assay (MRDR). Results indicated that serum vitamin A levels increased from the basal level of 0.86±0.13 µmol/l to 1.89±0.23 µmol/l in the Red Palmoil (RPO) group and from 0.74±0.09 to 1.94±0.21 µmol/l in the control vitamin A group. Dehydroretinol/Retinol (DR/R) ratio decreased from 0.073±0.025 to 0.023±0.004 in the RPO group and from 0.090±0.023 to 0.023±0.004 in the vitamin A group, indicating liver saturation with vitamin A after feeding RPO snacks, comparable to synthetic vitamin A. This study indicates that RPO is an efficient source of -carotene which is found to be bioavailable in all the subjects tested, hence it can be used for supplementary feeding programmes to combat vitamin A deficiency in target population.  相似文献   

7.
Traditional AOAC colorimetric procedures for carotenoid analysis are known to lack specificity and accuracy. Newer HPLC methods provide the investigator with a more precise tool for carotenoid quantification in foods and tissues. In the present studies, reverse phase HPLC was utilized to evaluate the - and -carotene content in raw and cooked leaves of lettuce, spinach and winged bean as well as in the carrot root. The vegetables were boiled or steamed and the true retention of - and -carotene in the cooked products was determined. Boiling for 30 minutes resulted in a 53 and 40% loss of -carotene from lettuce and carrots, respectively. Full retention or even an increase in -carotene content in boiled winged bean leaves and spinach was noted. Steaming resulted in very good retention of - and - carotene in all vegetables (83–139% retention). Thus, although cooking procedures (especially boiling) may result in oxidative loss of carotenoids in some vegetables, heat treatment increases the chemical extractability of - and -carotene in others. The presence of carotenoproteins in some vegetables may effect the heat stability of extractability of - and - carotene.  相似文献   

8.
The present investigation was conducted to study the concentration of ascorbic acid and -carotene in spinach and amaranth leaves as affected by various domestic processing and cooking methods which included storage of leaves in polythene bags or without packing for 24 and 48 hours in refrigerator at 5 °C; at 30 °C in polythene bags; drying (sun and oven); blanching (5, 10, 15 min); open pan and pressure cooking. Ascorbic acid content of fresh leaves was 624.1 to 629.0 mg and -carotene content was 35.3 to 53.1 mg/100 g dry weight. The percent loss of ascorbic acid ranged from 1.1 to 6.3 and 55.3 to 65.9 while lower losses (0.0 to 1.3 and 1.5 to 2.1) of -carotene were observed in leaves stored in refrigerator and at 30 °C, respectively. A markedly greater reduction in ascorbic acid and -carotene was observed in dried, blanched and cooked leaves. The study recommended the storage of leaves in refrigerator, drying in oven, blanching for shorter time and cooking in pressure cooker for better retention of these two vitamins.  相似文献   

9.
Summary -carotene has been oxidized with a lipoxidase-linoleate system. Chromatography of the products shows that several of the bands have spectra corresponding to epoxide of -carotene. Three of the other fractions have been examined more closely by spectrophotometric methods and it is suggested that they are conjugated polyene ketones.Oxidation of -carotene by a ferrous phthalocyanine — linoleate system shows that the products vary depending upon the physical state of the oxidizing system.
Zusammenfassung -Karotin wurde durch ein Lipoxydase-Linoleat-System oxydiert. Die Chromatographie der Oxydationsprodukte zeigt, dass mehrere Banden typische Spektren zeigen, die auf das Epoxyd von -Karotin hinweisen. Drei andere Fraktionen wurden mittels der spektrophotometrischen Methode genau untersucht; es wäre möglich, dass diese Substanzen konjugierte Polyen-Ketone wären. Die Oxydation von -Karotin durch ein System Eisen-2-Phthalocyanin-Linoleat zeigt, dass die Produkte variieren mit dem physikalischen Zustand des Oxydations-Systems.
Résumé Le carotène- a été oxydé par le système lipoxidase-linoléate. La chromatographie des produits d'oxydation montre plusieurs bandes dont les spectres correspondent aux époxydes du -carotène. Trois autres fractions ont été examinées de près par les méthodes spectrophotométriques, et il est possible de suggérer que ce sont des polyénes conjugués à fonctions cétones à qui nous ne pouvons pas encore donner de formules. L'oxydation du -carotène par le système phthalocyanine ferreux-linoléate, montre que les produits d'oxydation varient en fonction de l'état physique du système oxydant.
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10.
Twenty three cultivars of carrot (Daucus carota L.) roots consisting of fifteen local and eight exotic cultivars were analysed for various chemical constituents including dry matter, total soluble solids (TSS), -carotene, total and reducing sugars, phenolics, phosphorus, zinc, manganese, copper, iron, sodium potassium and ash. In addition other characteristics such as days to maturity, root weight and length, flesh thickness, core diameter, number of forked and cracked roots per plot have been studied. Yellow carrots were found to have maximum root length, water soluble carbohydrates and minimum -carotene content. The exotic cultivars were found to have higher TSS content than the local cultivars, while the latter cultivars had higher mineral contents than the former. However, on the average, dry matter content, total water soluble sugars, reducing and non-reducing sugars were found to be greater in exotic cultivars than in local ones, but -carotene, phenols and phosphorus contents were greater in local cultivars. A significant positive correlation between -carotene content, ash percentage and days to maturity was observed. A wide variation in chemical constituents and plant characteristics was observed indicating a high genetic variability in the material under study.  相似文献   

11.
Leafy vegetables are highly perishable and their shelf life depends on duration and conditions of storage. A low cost storage structure was used to extend the shelf life of amaranth and fenugreek and their quality was evaluated on the basis of retention of -carotene, ascorbic acid and chlorophyll during storage. Losses of -carotene ranged from 46.5 to 85.0% for amaranth and 24.0 to 73.0% for fenugreek depending on duration and conditions of storage. Similarly ascorbic acid retention varied from 9–32% for amaranth and 23–80% for fenugreek. Results showed that the degradation of quality parameters was faster at ambient conditions and packaging of leaves in low density polyethylene bags was beneficial in improving shelf life and nutritive value. Low cost storage structure was similar to low temperature storage for retention of -carotene, ascorbic acid, chlorophyll content and enhancement of shelf life.  相似文献   

12.
Zusammenfassung Gute Bekömmlichkeit, hohe Gehalte an dem Provitamin A Carotin sowie eine gute therapeutische Wirkung bei der gefürchteten Säuglings-Enteritis machen die Möhre zum wichtigsten Gemüse in der Säuglings- und Kleinkinder-Ernährung.Entwicklungsphysiologische Untersuchungen gaben Aufschluß über die Bildung der ätherischen Öle in Speicherwurzeln von 2 Möhrensorten in Verbindung mit anderen wertgebenden Inhaltsstoffen. In einer Vegetationszeit von fast vier Monaten entwickelten sich die Möhren vom Fadentyp über Bündelmöhre zur verkaufsfähigen Möhre ohne Kraut und zur überständigen Ware. Der Gehalt an ätherischen Öl nahm mit zunehmender Wurzelentwicklung stark ab, der Carotingehalt dagegen stark zu. Ein ähnliches antagonistisches Verhalten zeigten die Mono- und Disaccharide.5 jährige Untersuchungen der ätherischen Öle und ihrer Bestandteile von 8 verschiedenen Sorten und Herkünften von Spätmöhren des gleichen Standorts (Geisenheim/Rheingau) gestatteten statistische Auswertungen über signifikante Abhängigkeit von genetischen und ökologischen Faktoren.Von den 13 identifizierten Bestandteilen des ätherischen Möhrenöls ließen 5 (-Pinen, Camphen, Myrcen, -Phellandren und Bisabolen) weder einen gerichteten bzw. statitistisch gesicherten Einfluß der Sorte, noch einen solchen der Witterung des Vegetationsjahres erkennen.Von den übrigen 8 Komponenten konnten 3 (Sabinen, l-Limonen und Caryophyllen) sowohl in genetischer Hinsicht über die jeweilige Sorte als auch ökologisch über die Witterung während der Vegetationsjahre beeinflußt werden. 2 Bestandteile des ätherischen Möhrenöls (-Pinen und -Terpinen) erwiesen sich als nur sortenabhängig, während 3 (-Terpinen, p-Cymol und Terpinolen) nur auf Witterungseinflüsse in den verschiedenen Jahren reagierten.Die wohlschmeckende Herkunft IV der Sorte Lange rote stumpfe ohne Herz mit relativ hohem Carotingehalt hatte gesicherte Befunde über besonders hohe l-Limonen- und -Pinengehalte, aber sehr geringe Sabinen- und Caryophyllengehalte. -Pinen hatte in einer unserer früheren Untersuchungen gegen häufige Erreger der Säuglingsenteritis (Escherichia coli Stamm 0127 :B 8 undStaphylococcus aureus) die weitaus beste bakterizide und bakteriostatische Wirkung aller damals identifizierten Bestandteile des ätherischen Möhrenöls erbracht. Die bakteriostatische Wirkung erwies sich bei l-Limonen als genau so stark gegen E. coli wie bei -Pinen. Nur gegenStaphylococcus aureus war -Pinen wirksamer als l-Limonen.Auf Grund dieser und weiterer, hier nicht genannter Ergebnisse werden Möglichkeiten zur Züchtung wertstoffreicher Diätmöhren erörtert. In diesem Zusammenhang steht auch generell die biochemische Qualitätsbeurteilung im Vergleich zu der der Handelsklassen und EWG-Qualitätsnormen zur Diskussion. Auf die Doppelrolle des ätherischen Möhrenöls einerseits als erwünschtes Diäteticum und andererseits als unerwünschtes Lösungsmittel und Rückstandsreservoir für fettlösliche, toxische Pestizide (Dienmittel und Phosphorsäureester) wird abschließend hingewiesen.
Chemotaxonomic studies on carrots (Daucus carota L. ssp. sativus (Hoffm.))The composition of the essential oil constituents of the carrot root in response to cultivar and site
Wholesomeness, high contents of carotene and a good therapeutical effect toward the feared infant's enteritis are the reason why carrots play a most important rôle in infant feeding.Physiological studies in tap roots of 2 carrot cultivars gave particulars of the formation of essential oils as well as of other constituents important in nutrition during a 4 month's cultivation during summer. Up to beginning with the primary development of root to the bunched carrot state, further to the state of normal ripeness and to a rather overripe state the contents of essential oils decreased considerably, while carotene contents showed an entirely reversed tendancy during the same period of development. A similar antagonistic reaction was observed in the behaviour of Mono- and Disaccharides.5 year's determinations of essential oil and its constituents of 8 different cultivars and races of carrots grown every year on the same site (Geisenheim/Rhine) allow statistical evaluations regarding significant dependence on genetical and ecological factors.5 out of 13 identified constituents of essential root oil of carrots (-pinene, camphene, myrcene,a-phellandrene and bisabolene) did not react on any influence of cultivars and weather conditions in different years. On the other hand 3 out of the remaining 8 constituents (sabinene, l-limonene, caryophyllene) were influenced both by cultivars and weather conditions. 2 constituents (-pinene, -terpinene) were found to be dependent on cultivars, while 3 (-terpinene, p-cymole, terpinolene) proved to react on weather conditions in different years.Race IV of cultivar Long red stumpy without core relatively high in carotene content and of very good taste showed significant very high contents in l-limonene and in -pinene, but very low ones in sabinene and in caryophyllene. In earlier investigations of our institute -pinene proved to be far more efficient regarding bactericidal and bacteriostatical effect against germs ofEscherichia coli (race 0127 :B 8) andStaphylococcus aureus, both feared causes of infant's enteritis, than any other of the investigated essential oil constituents of carrot root. As far as the bacteriostatic effect was concerned l-limonene proved to be as efficient againstE. coli as -pinene, but not againstStaphylococcus aureus. Here -pinene was found more efficient.Possibilities to breed carrots of high dietetic efficiency and problems of quality evaluation on a biochemical scale are discussed finally. The double rôle of essential root oil of carrots on one side as a desired dieteticum in infant's nutrition on the other side as solvent of undesired fat soluble toxic pesticides (cyclo dienes and organophosphates) is worth to be mentioned.
Résumé Appetissantes, riches en carotène provitamin A, capables d'agir contre la redoutable entérite des nouveaux nés, les carottes sont le légume de plus important dans l'alimentation des nourrissons et des jeunes enfants.La formation des huiles essentielles a été étudiée au cours du développement ontogénique dans deux variétés de carottes, en liaison avec d'autres constituants importants des tissues. En quatre mois de végétation, les carottes passent du stade filiforme au stade cordiforme, et de là au stade de légume commercialisable, sans la partie aérienne, et de bonne conservation. Le taux d'huiles essentielles diminue fortement au cours du développement de la racine, tandis que le taux de carotène augmente beaucoup. Les mono- et disaccharides se comportent aussi de façon antagoniste. Nos recherches ont porté, durant 5 ans, sur les constituants des huiles essentielles de 8 variétés et selections différentes, mais cultivées dans les mêmes conditions (Geisenheim dans le Rheingau); l'exploitation statistique des résultats permet d'établir des relations significatives avec les facteurs génétiques et écologiques.Sur 13 constituants identifiés dans l'huile essentielle de carottes, 5 (-pinène, camphène, myrcène, -phellandrène, bisabolène) ne paraissent dépendre ni de la variété, ni du climat, d'après les données statistiquement valables.Parmi les 8 autres constituants, 3 (sabinène, l-limonène, caryophyllène) dépendent de la variété, et du climat de l'année de culture. 2 constituants (-pinène, -terpinène) semblent ne dépendre que de la variété, 3 autres (-terpinène, p-cymol, terpinolène) ne varient que sous l'action des facteurs climatologiques des diverses années. La variété longue rouge arrondie sans coeur de la sélection IV, remarquable par son goût agréable, à taux de carotène relativement, élevé, a, d'une façon certaine, des taux de l-limonène et de -pinène particulièrement élevés, des taux très faibles de sabinène et de caryophyllène.Des recherches antérieures nous avaient montré que le -pinène a de beaucoup la meilleure action bactéricide et bactériostatique contre les agents fréquents de l'entérite des nourrissons (Escherichia coli, race 0127 :B 8, etStaphylococcus aureus) en comparaison avec tous les autres constituants identifiés dans les huiles essentielles des carottes.L'action bactériostatique du l-limonène contre leE. coli est exactement aussi grande que celle du -pinène; cependant le -pinène est plus actif contreStaphylococcus aureus que le l-limonène.Ces résultats, et d'autres que nous ne pouvons que résumer ici, permettent de sélectionner des carottes diététiques riches en principes utiles. La qualité biochimique d'une façon générale se discute par rapport aux catégories commerciales et aux normes de qualité du marché commun.Signalons pour terminer que les huiles essentielles de carottes, qui apparaissent comme des élements de la qualité diététique, sont aussi des dissolvants indésirables et des réservoirs de résidus pour des pesticides liposolubles, et toxiques (produits diéniques, esters phosphorus).

Die Deutsche Forschungsgemeinschaft Bad Godesberg unterstützte teilweise das Forschungsvorhaben finanziell, wofür ich auch an dieser Stelle meinen Dank aussprechen möchte.

Vortrag gehalten auf der gemeinsamen Tagung der Internationalen Vereinigung zur Erforschung der Qualität von Nahrungspflanzen (CIQ) und der Deutschen Gesellschaft für Qualitätsforschung (Pflanzliche Nahrungsmittel) (DGQ) in Mainz (25.–27. März 1969) am 25.3.1969.  相似文献   

13.
-carotene in leaf protein extracted from some species is destroyed in a few days when incubated with salt as a preservative. Its shelf-life can be greatly extended by pretreatment with oxalate, ascorbate mercaptans, phenolic substances, extracts made from leaves in which carotene is more stable, and by tight compaction. Treatment with alum reverses the protective effect of these chemical pretreatments, it also increases the lability of carotene in leaf protein extracted from species which usually give a relatively stable product. In these preparations of leaf protein, which were heated to 90 °C during preparation, carotene is only partially extractable into some solvents which are miscible with water. It seems therefore to be present in more than one state, but differences in extractability could not be correlated with differences in lability.  相似文献   

14.
Summary The effects of five genes which affect carotenoid differences in the fruits ofLycopersicon are discussed. Green and orange-fruited species contain a gene which, when introduced intoesculentum can cause production of -carotene, as shown first withhirsutum hybrids byLincoln &Porter at Purdue. A gene, ghost, gives rise to a form of albinism, and phytoene accumulation is observed. The interpretation of the data in terms of a biochemical sequence involving phytoene, lycopene and -carotene is by no means self-evident and at this juncture, explanations must be considered only as working hypotheses.
Zusammenfassung Die Wirkung von fünf Genen, die die Differenzierung von Karotinoiden in Früchten vonLycopersicum beeinflussen, wird diskutiert. Die Sorten mit grünen oder mit orangefarbigen Früchten enthalten ein Gen, das, in die Art esculentum eingeführt, in der Lage ist, die Bildung von -Karotin zu veranlassen, wie als ersteLincoln &Porter für Hybriden von hirsutum festgestellt haben. Ein Gen Ghost bewirkt eine gewisse Form von Albinismus; dabei beobachtet man eine Anhäufung von Phytoen.Aus diesen Tatsachen kann man nicht schliessen, dass ein biochemischer Zusammenhang zwischen Phytoen, Lycopin und -Karotin bestände; bei dem heutigen Tatbestand kann man dies höchstens als Arbeitshypothese betrachten.
Résumé Discussion sur l'action des cinq gènes qui déterminent la différenciation des caroténoïdes dans les fruits deLycopersicum. Les espèces à fruits verts ou oranges contiennent un gène qui, introduit dans l'espèceesculentum, peut déterminer la production de -carotène, ainsi queLincoln &Porter l'ont montré les premiers pour les hybrides dehirsutum. Un gène phantome détermine une certaine forme d'albinisme, et corrélativement s'observe l'accumulation de phytoène.L'interprétation de ces données comme preuve d'une filiation biochimique phytoène-lycopène--carotène n'est nullement évidente; dans l'étant actuel des faits, il ne peut être question que d'une hypothèse de travail.
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15.
Low cost supplementary products using maize were developed and made using extrusion. -carotene rich sources like curry leaf, carrot, red palm oil were used at different level to increase vitamin A precursor Levels and, therefore, vitamin A. Incorporation of curry leaf powder and carrot powder at 30 percent level and 30:70 blend of red palm oil and groundnut oil were found to be more acceptable than the products made with other levels. These products were tasted for acceptability by preschool children and were analysed for energy, protein, fat and -carotene contents. The control, fresh and stored supplementary products contained 1.707, 1.922, 1.919 MJ, 11.0, 11.6, 10.36 g protein, 10.2, 10.4, 9.64 g fat, 0, 7.37,6.72 mg -carotene per 100g, respectively. The loss of -carotene in processing and storage of curry leaf and carrot supplemented products was 13.69, 6.25 and 20.24, 8.06 percent, respectively.  相似文献   

16.
Summary The influence of various factors of plants production upon the quality of vegetables was determined.Significant differences in the content of 9 mineral elements were found in 12 tested varieties of snap beans. Proper breeding can enhance the ability of accumulation of desired elements by snap bean varieties.The effect of different forms of nitrogen, phosphorus and potassium upon the carotenoid content in the carrots were examined. Nitrates were found better than urea form of nitrogen; monocalcium and tricalcium phosphates were similar in action and potassium sulphate had here greater influence than the chloride form.Experimental evidence, accumulated over a period of 3 years, is given that herbicides, recommended for particular kind of vegetables, do not decrease the nutritional values of the crop. Tomatoes, carrots, root parsley and onions were analysed for contents of dry matter, vitamin C, -carotene and total acidity.Effects of Betokson/-naphtoxy acetic acid, with a wetting agent/ and Ethrel upon the ripening of tomatoes on the vine were compared. Betokson increased more significantly the fruit set and the ripening rate of the fruits. Ethylene and Ethrel were compared in their influencing the ripening of harvested green tomatoes. Ethylene was found slighty better, but the differences were not significant.
Zusammenfassung Es wurde der Einfluß verschiedener Anbaufaktoren auf die Qualität von Gemüsen dargelegt.Große Unterschiede im Gehalt an 9 Mineralstoffen ergaben sich in 23 analysierten Bohnensorten. Die Unterschiede an hohen erwünschten Mineralstoffgehalten sollen genetisch durch Züchtung fixiert werden.Es wurde der Einfluß von zwei Formen der Stickstoff-, Phosphor- und Kali-Verbindungen auf Gehalt von Carotinoiden in Möhren untersucht. Nitrat-Stickstoff hatte eine bessere Wirkung als Harnstoff-Stickstoff; Monocalcium-Tricalcium-Phosphate hatten einen ähnlichen Einfluß und mit Kali-Sulfat-Düngung war der Gehalt von Carotinoiden höher im Vergleich zur Düngung mit Kali-Chlorid.Dreijährige Versuchsergebnisse haben gezeigt, daß Herbizide, die zur Vernichtung von Unkraut in verschiedenen Gemüsearten empfohlen werden, den biologischen Wert der Gemüseprodukte nicht erniedrigen. Tomaten, Möhren, Wurzelpetersilie und Zwiebeln
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17.
Résumé Nous avons obtenu avec un rendement acceptable des échantillons de -sitostérol purs par le procédé suivant: la double liaison en 22 d'un propionate de stigmastérol de pureté 95% est hydrogénée en présence de Pd/C. Le propionate de -sitostérol formé est isolé par chromatographie préparative sur couche mince d'alumine imprégnée de nitrate d'argent.Nous avons contrôlé la pureté du produit obtenu par spectrométrie de masse.
Summary Samples of pure -sitosterol have been obtained with a satisfactory yield by the following method.The double linkage in 22 of a stigmasterol propionate of 95% purity is hydrogenated in the presence of Pd/C. The -sitosterol propionate is isolated by preparatory thin layer chromatography on silver nitrate impregnated aluminium.The purity of the product has been verified by mass spectrometry.
Zusammenfassung Wir erhielten mit annehmbarem Wirkungsgrad Muster von reinem -Sitosterin nach folgender Methode:In Gegenwart von Pd/C wird die Doppelbindung bei 22 eines Stigmasterin-Propionates mit 95%-er Reinheit hydriert. Das gebildete -Sitosterin-propionat wird durch präparative DC auf mit Silbernitrat imprägnierter Aluminiumoxidschicht isoliert.Die Reinheit des erhaltenen Produktes wurde mit dem Massenspektrometer geprüft.

Note de laboratoire  相似文献   

18.
Proximate composition and mineral content of raw and cooked leaves of two edible tree spinach species (Cnidoscolus chayamansa and C. aconitifolius), known locally as chaya, were determined and compared with that of a traditional green vegetable, spinach (Spinicia oleraceae). Results of the study indicated that the edible leafy parts of the two chaya species contained significantly (p<0.05) greater amounts of crude protein, crude fiber, Ca, K, Fe, ascorbic acid and -carotene than the spinach leaf. However, no significant (p>0.05) differences were found in nutritional composition and mineral content between the chaya species, except minor differences in the relative composition of fatty acids, protein and amino acids. Cooking of chaya leaves slightly reduced nutritional composition of both chaya species. Cooking is essential prior to consumption to inactivate the toxic hydrocyanic glycosides present in chaya leaves. Based on the results of this study, the edible chaya leaves may be good dietary sources of minerals (Ca, K and Fe) and vitamins (ascorbic acid and -carotene).  相似文献   

19.
Summary Some data on growth, development, and mineral nutrition of two varieties of groundnuts — Improved Virginia Bunch and Spanish-33 — under irrigation are reported.There was almost no difference in the yield of pods of the two varieties, but the yield of hay was much lower in Spanish. Spanish had also a lower total yield of dry matter, a smaller leaf area, and fewer branches than Virginia.In both varieties a negative correlation was found between Net-Assimilation-Rate and Leaf-Area-Index. Under the conditions of our observations, the highest rate of dry matter accumulation per plant was at a Leaf-Area-Index of approximately 3.There was a gradual decrease in the nitrogen content of the vegetative parts from the beginning of the season until harvest time. Most of the final amount of nitrogen was taken up before the end of August. After that, there was a transportation of this element to the newly formed pods. Pods and kernels of the Spanish variety had a higher nitrogen content than Virginia. The total amount of nitrogen taken up by the plants was equal in both varieties, 22 g per sq.m.A slight decrease in the phosphorus content of the vegetative parts was found throughout the season. The percentages of phosphorus were roughly equal, but the final amounts taken up by the two varieties were different: 3.16 g P per sq.m in Virginia, 2.34 in Spanish. The plants continued to take up phosphorus until harvest time.As the season progressed, the percentages of potassium decreased in the vegetative parts as well as in the pods and pegs. The stems had the highest potassium contents. Almost all the final amount of potassium was taken up by August. Total amounts of potassium taken up by the plants were found to be 5.7 g per sq.m. in Virginia, 3.4 in Spanish.The authors wish to acknowledge the assistance of Miss HelenaBodek in carrying out the chemical analyses. This work was aided by a grant by the Israel Groundnut Production and Marketing Board.
Zusammenfassung Der Bericht enthält Angaben über Wachstum, Entwicklung und mineralische Ernährung von zwei unter Bewässerung angebauten Erdnuss-Sorten — Improved Virginia Bunch und Spanish — 33.Die zwei Sorten unterschieden sich kaum in ihrem Hülsenertrag, dagegen aber war der Heuertrag der Sorte Spanish erheblich niedriger. Spanish war auch geringer als Virginia in allgemeinem Trockensubstanzertrag, Blattoberfläche und Stengelzahl.In beiden Sorten wurde eine negative Korrelation zwischen Rein-Assimilations-Wert und Blatt-Flächen-Index gefunden. Bei den Bedingungen, unter welchen unsere Beobachtungen angestellt wurden, ergab sich die höchste Trockensubstanzansammlung bei einem Blatt-Flächen-Index von annähernd 3.Eine allmähliche Abnahme des Stickstoffgehalts der vegetativen Organe im Laufe der Entwicklungsperiode bis zur Erntezeit wurde beobachtet. Der Hauptteil der endgültigen Menge des Stickstoffs wurde bis Ende August absorbiert. Nach diesem Termin fand eine Überführung des Stickstoffs in die neugebildeten Hülsen statt. Hülsen sowohl wie Samen der Sorte Spanish hatten einen höheren Stickstoffgehalt als Virginia. Die Gesamtmenge des durch die Pflanzen absorbierten Stickstoffs war in beiden Sorten gleich und betrug 22 g pro m2.Eine geringe Abnahme des Phosphorgehalts der vegetativen Organe im Laufe der Entwicklungsperiode wurde festgestellt. Der Prozentsatz des Phosphors der zwei Sorten war beinahe gleich, jedoch die Gesamtmenge des durch die Pflanzen aufgenommenen Phosphors betrug 3.16 g pro m2 bei der Sorte Virginia und 2.34 bei der Sorte Spanish. Die Phosphorabsorption der Pflanzen hielt bis zur Enrte an.Im Laufe der Entwicklungsperiode nahm der Kalium Prozentsatz in den vegetativen Organen sowohl wie in den Hülsen und Stielen ab. Die Stengel ergaben den höchsten Kaliumgehalt. Im August war beinahe die endgültige Menge des Kaliums aufgenommen. Die Gesamtmenge des durch die Pflanzen absorbierten Kaliums betrug 5.7 g pro m2 bei der Sorte Virginia und 3.4 bei der Sorte Spanish.
Résumé Quelques données sur la croissance, le développement et la nutrition minérale de deux variétés d'arachides — Improved Virginia Bunch et Spanish 33 sont présentées ici.Les deux variétés ont donné des rendements en gousses très voisins alors que le rendement en foin de la variété Spanish a été très inférieur. Pour la variété Spanish, on a eu, également, un rendement total en matière sèche plus faible, une surface foliaire plus réduite et un nombre de branches moindre que pour la Virginia.Chez les deux variétés, on a trouvé une correlation négative entre le Taux d'Assimilation Nette et l'Index de Surface Foliaire. Dans les conditions de nos observations, le taux maximum d'accumulation de matière sèche correspond à un index voisin de 3.Le taux d'azote contenu dans les organes végétatifs a diminué progressivement du début de la saison jusqu'au moment de la récolte. La plus grande partie de la quantité finale d'azote a été fixée avant la fin août. Après cette date, il y a eu transport de cet élement vers les gousses nouvellement formées. Le taux d'azote des gousses et des graines de la variété Spanish est plus éléve que celui des gousses et graines de Virginia. La quantité totale d'azote prélevé par les plantes a été la même pour les deux variétés, soit 22 g par m2.On a noté une légère diminution du taux de phosphore des organes végétatifs au cours de la saison. Les pourcentages de phosphore ont été très voisins, mais les quantités totales prévelées par les plantes des deux variétés ont été différentes: 3.16 g P par m2 pour la variété Virginia et 2.34 pour la Spanish. Les plantes ont continué à prélever du phosphore jusqu'au moment de la récolte.A mesure que la saison a avancé, le pourcentage de potassium des organes végétatifs ainsi que des gousses et des gynophores a décru. Les tiges out contenu les taux de potassium les plus élevés. La presque totalité du potassium a été prélevé avant le mois d'août. Les quantités totales de potassium prélevées par les plantes ont été de 5.7 g par m2 pour la variété Virginia et de 3.4 pour la variété Spanish.

With 10 figs.  相似文献   

20.
Green leafy vegetables are the most underexploited class of vegetablesdespite high nutritional value. Reports on nutritional composition andstorage of some of the fresh leaves are available but the storage behaviorof dehydrated leaves apparently has not been studied. Therefore, in thepresent study, two green leafy vegetables, savoy beets (Beta vulgarisvar. bengalensis) and fenugreek (Trigonella foenumgraecum) were dehydrated in a low temperature drier and stored for9 months under ambient and cold stored conditions after packaging insingle or double layers of high density polyethylene film (200 gauge). Thequality was determined on the basis of retention of -carotene,ascorbic acid and chlorophyll, and the extent of browning during storage.Retention of these quality characteristics depended on the crop and storageconditions. Double packed and cold stored samples of fenugreek retained67% -carotene, whereas savoy beet leaves retained only 57% ofthe initial -carotene under similar conditions. Similarly, higherretention of ascorbic acid and chlorophyll, and lower browning wasobserved in double packed, cold stored samples. Results indicated theefficacy of double packed and cold stored samples over other combinations.  相似文献   

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