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1.
Abstract

Inactivation and riactivation of enzymes in endosperms of castor bean seeds. — On the basis of previous results, the possibility has been investigated of the reversible interconversion of active and inactive form of enzymes in castor bean seeds, during their development.

The results described here indicate that:

  1. the activity of some glycolytic enzymes increases greatly (81% and 400% increase of, respectively, Gl-6-P-dehydrogenase and aldolase) upon incubation of dry seeds for few hours at 4 °C.

  2. The decrease of enzyme activity upon dehydration of seeds and the increase during the subsequent imbibition can be shown reproducibly.

  3. This same observation is made for oxygen uptake.

These results are interpreted to indicate the reversible inactivation of enzymes caused by dehydration of seeds.  相似文献   

2.
3.
Abstract

ACTION OF LIGHT ON SEEDLING GROWTH IN A YELLOW-GREEN MUTANT OF TRITICUM DURUM DESF. — Dry grains of Triticum durum cv. « Cappelli » and its radiation-induced yellow-green mutant were sown in sand in four environment, different for light conditions (daylight, artificial light, ultraviolet rays, darkness), having all the same temperature (23°C.). Seven days after sowing, the following data were registered: a) growth (in cm.) of the shoot and of the longest root; b) fresh weight (in gr.) of shoots and roots; c) water content of shoots and roots.

The following main results were obtained:
  1. the yellow-green mutant always shows less growth and less weight increase than normal « Cappelli », with the exception of the seedlings grown at daylight, which have shorter shoots and longer roots than the normal « Cappelli » but the same weight:

  2. artificial light, besides depressing the growth of the roots of the yellow-green mutant, which becomes green under these conditions, induces a remarkable decrease in the water content of the roots of the two wheats.

  相似文献   

4.
Summary

The Author studies the action of the presence of the ear and its parts in the growth of the stem and in the value of the water of traspiration and of assimilation in the higher leaf. The stet shows:

  1. A removed ear, not yet mature, exerts a depressing effect upon the development of the stem and ucon the leaf's functions.

  2. The threads and the pistils removed inhibit the enlongament of the stem and alter the functions of leaves.

  3. Maturing seeds removed cause trubles on the function of the vegetative organ.

This phenomen is due to the presence of an hormonical substances elaborated in the riproduction's orgas, which are considerated the centre of functional correlation.  相似文献   

5.
Abstract

Nucleic Acids in Ripening of Castor Bean Endosperm. - I. Quantitative and Qualitative Changes of total RNA. — The ripe Castor Bean seed endosperm (Ricinus Communis var. Sanguinea) has a very low level of nucleic acids and particularly of ribosomal RNA. However, they rapidly increase during the germination of the seed (S. Cocucci et al., Acc. Naz. Lincei, 38, 545, 1965).

The behaviour of the nucleic acids, obtained by phenol extraction from Castor Bean seed endosperm at different ripening stages, is the following:

  1. From the moment when the developing seed has reached the maximal fresh weight to the moment of its complete ripening, the RNA content decreases from about 700 μg per seed to about 200 μg.

  2. During the same period the DNA level (about 13–15 μg per seed) remains nearly costant.

  3. Fractionation by sucrose density gradient of the phenol extracted RNA (H. L. Sanger and C. A. Knight, Biochem. Biophys. Reserch Commun., 13, 445, 1963) shows that during the ripening of the seed the high molecular weight RNA decreases much more than the low molecular weight RNA.

  4. Radioactive phosphate injected in the seeds is incorporated in the RNA at all the stages. Fractionation by sucrose density giadient shows that the phosphate is essentially incorporated in low molecular weight RNA and there is pratically no labelling of the heavier RNA after quite a long period (2 hr.).

These data suggest that the decrease of the RNA during the ripening of the seed can be due to a fall in the ability to synthesize high molecular RNA.  相似文献   

6.
The following procedure for staining Negri bodies in sections is based on methods previously described by MacNeal, by Haynes, and by Richter:

Fixation:
  1. 1. Zenker's solution 4 hours at 37°C or Dominici's 3 hours.

  2. 2. 70% alcohol, 12 to 18 hours at room temperature.

  3. 3. 80% alcohol, about 5 to 6 hours.

  4. 4. 90% alcohol, about 4 to 6 hours.

  5. 5. Absolute alcohol about 16 hours.

  6. 6. Ether and absolute alcohol aa, about 8 hours.

  7. 7. 16 to 24 hours in the following mixture: celloidin 1 g., methyl salycilate 25 cc., abs. alcohol 25 cc., ether 25 cc.

  8. 8. Chloroform and paraffin, 2 to 3 hours.

  9. 10. Paraffin, 1 to 1 1/2 hours.

  10. 11. Embed.

staining:
  1. 1. Cut sections 4 to 5 μ.

  2. 2. Bring section to water and cover with Lugol's iodine for 10 minutes.

  3. 3. Decolorize with a 2% sodium thiosulfate (hypo).

  4. 4. Wash thoroly with water.

  5. 5. Cover with a mixture of equal parts of 0.5% phloxine and 1% eosin Y (National Aniline brand) and leave for 15 minutes.

  6. 6. Wash with water and stain 2 to 5 minutes in 0.1% azure B (National Aniline).

  7. 7. Wash with 96% alcohol and decolorize in a mixture of 2 parts absolute alcohol with 1 part clove oil, ordinarily for not more than 1/2 to 1 minute.

  8. 8. Dehydrate rapidly, clear, and mount in Yucatan Elemi.

  相似文献   

7.
  1. The catalase activity of Candida tropicalis pK 233 was induced by hydrocarbons but not by glucose, galactose, ethanol, acetate or lauryl alcohol.

  2. The induction of the catalase activity depending upon hydrocarbons was sensitive to cycloheximide but not to chloramphenicol.

  3. Glucose repressed strongly the induction of the catalase activity by hydrocarbons but galactose did not affect seriously.

  4. When C. tropicalis was incubated with hydrocarbons, the appearance of microbodies was observed electronmicroscopicaliy.

  相似文献   

8.
  1. The 1C conformation was estimated for α-d-galactopyranosiduronic acid moiety of pectic acid in the permethylated derivative dissolved in 1 n NaOD-D2O and in the peracetylated derivative dissolved in dimethyl sulfoxide-d6, and the C1 conformation was estimated for some derivatives of d-galactopyranuronic acid in chloroform-d by NMR spectroscopy.

  2. Random conformation of the whole macromolecule was estimated for pectic acid in water on the basis of no appearance of any induced Cotton effects in the 200 ~ 700 mμ region in the ORD spectra of pectic acid-anionic dye complexes.

  3. The conformation was supported by the fact that the rate of periodate oxidation of pectic acid at 5° was slightly decreased in comparison with that of amylase in 7 m urea solution.

  相似文献   

9.
In Fortführung seiner Untersuchungen über neotropische Acanthocinini veröffentlicht der Verfasser hiermit Beschreibungen von folgenden neuen Gattungen:
  • Nyssodrysilla nov. gen. mit N. irrorata (Melzer) aus Brasilien als Generotype, N. viliata (Melzer), comb, nov., aus Brasilien und N. lineata nov. spec, aus Peru.

  • Nyssodrysola nov. gen. mit N. stictica nov. spec. aus Peru als Generotype.

  • Sciadosurus nov. gen. mit S. albobrunneus nov. spec. aus Peru als Generotype.

  • Acarinozineus nov. gen. mit A. striatus nov. spec. aus Peru als Generotype und A. spinicornis nov. spec, aus Mexiko.

  • Alcathousites nov. gen. mit A. chaclacayoi nov. spec. aus Peru als Generotype.

  • Xylergatina nov. gen. mit X. pulcher (Lane) aus Peru als Generotype.

  • Xylergatoides nov. gen. mit X. asper (Bates) aus Brasilien und Argentinien als Generotype.

Ferner werden revidiert die Gattungen:
  • Xylergates Bates, Generotype X. lacteus (Bates), mit Beschreibung der beiden neuen Arten X. elaineae aus Peru und X. dorotheae aus Britisch‐Guayana.

  • Chaetanes Bates, Generotype C. setiger (Bates), mit Beschreibung der drei neuen Arten C. costulatus aus Peru, C. nigrobasalis aus Brasilien und C. apicalis aus Französisch‐Guayana.

  • Wo es erforderlich ist, sind Bestimmungstabellen gebracht und die Arten abgebildet.

  相似文献   

10.
11.
Summary

The Author studies with the weighing method the action of plant-eater insects on the alteration of the substances fresch and dry in the hust leaves and he comes to the following conclusions:

  1. The fresh substance stand less alterations in the leaves with the excavated border than in the sound leaves, the dry substance is less in the hust leaves than in those sound.

  2. The fresh substance shows little waverigs in the leaves notched on alone side of the border, but the dry substance is always inferior in the hust leaves than in the sound half and in those entire.

  3. The substances fresh and dry are less in the bored leaves than in the sound, the dry substance shows little alternations in those bored in one or the other half of the border.

This would indicate that the traumatic action of insects causes in the leaves a depresson of the cellular swuelling, whih determines a bigger mobilization of the dry substanc's elements than in the sound leaves.  相似文献   

12.
Abstract

The Influence of Short Periods of Lighting with Different Wavelengths on the Orcadian Changes of the Enzymatic Digestive Activities in Palaemon serratus (Crustacea, Natantia)

The effect of light on the circadian rhythms of digestive activities in the Shrimp Palaemon serratus have been studied.

  1. Continuous darkness leads in a few days to a disappearance of the variations of the circadian rhythms of digestive enzymes while these rhythms go on in continuous light.

  2. Short (1 or 2 hrs) and low intensity flashes of white light are effective in bringing on the reappearance of rhythmic variations in darkness.

  3. We have been able to establish an isoquantic spectrum of action of the light. Two values of wavelength appears to account for a maximum sensibility of the shrimp: one in ultraviolet light and an other one, more important, in the green (λ=544 nm).

  4. In green light it is possible to obtain the same effect of light by decreasing the time of stimulation to 5 or 10 mn and in increasing the total quantity of energy. Significant responses are obtained with total energy greater than 10000 pE. cm‐2.

  相似文献   

13.
During the course of studies on the oxidative metabolism of d-sorbitol by acetic acid bacteria, it was found that d-sorbitol was almost quantitatively converted to 5-keto-d-fructose via l-sorbose by a certain strain of Gluconobacter suboxydans. In addition to 5-keto-d-fructose, three γ-pyrone compounds, kojic acid, 5-oxymaltol, and 3-oxykojic acid, 2-keto-l-gulonate, and several organic acids such as succinic, glycolic, and glyceric acids were confirmed in the culture filtrate of this bacterium.
  • The most suitable carbon source for 5-ketofructose fermentation by Gluconobacter suboxydans Strain 1 was confirmed to be d-sorbitol or l-sorbose using growing and resting cells. d-Fructose had little effect on the formation of this dicarbonylhexose.

  • The optimal pH for the formation from l-sorbose by intact cells was found to be at 4.2.

  • The activity of the pentose phosphate cycle in the resting cells was calculated as 13~17 μatoms/hr/mg of dry cells by the use of the manometric techniques.

  • There was no strain tested so far which could accumulate a large amount of 5- keto-d-fructose from d-sorbitol except this bacterium.

  • The experimental results shown in this paper makes the prediction that a certain dehydrogenating system of l-sorbose is functional in the organism, and the metabolic pathways of d-sorbitol via l-sorbose and 5-keto-d-fructose is proposed.

  相似文献   

14.
  1. l-Aspartate was found to replace l-asparagine in the protective action from acid inactivation of l-asparaginase (EC 3.5.1.1) produced by Escherichia coli A–1–3 and at the same time to inhibit the proteolytic inactivation by α-chymotrypsin.

  2. l-Asparaginase changed in its chromatographic properties in the presence of l-aspartate and became to be absorbed on the CM Sephadex column.

  3. The sedimentation patterns of l-asparaginase at pH 3.5 were identical either in the presence or absence of l-aspartate, showing partial dissociation. But the reversibility to the active state was observed only in the enzyme dissolved in the solution containing l-aspartate.

  4. l-Aspartate did not prevent the enzyme either from the dissociation into subunits or from decrease in the activity by urea.

  5. High concentration of l-aspartate was shown to inhibit the l-asparagine hydrolysis reaction.

  6. l-Aspartate was suggested from ORD measurements to cause changes in the higher structure as well as the ionic properties or proteolytic inactivation.

  相似文献   

15.
Riassunto

L'A. ha studiato l'embriogia della Vinea difformis Pourr. ed ha potuto stabilire che:

  1. l'archisporio è pluricellulare e possono svilupparis talvolta pi[ugrave] cellule madri;

  2. normalmente solo una cellula madre arriva a maturità;

  3. delle quattro megaspore solo una è fertile e precisamente la pi[ugrave] calazale;

  4. lo sviluppo del gametofito è del tipo Normale cioè Monomegasporiale con oangio emisporiale.

Ha inoltre risontrato una anomalia di sviluppo constituita da un gametofito binucleato abnorme per ritardo delle divisioni nucleari cispetto all'acerescimento che è quello di un gametofito ottonucleato.  相似文献   

16.
The nutritional values of nonessential amino acids as the nitrogen source in the crystalline amino acid diet for the chick growth were examined. The nitrogen of the nonessential amino acids in the basal diet for chick was substituted for a nonessential amino acid to be tested on the nitrogen base. The experimental methods were the same as in the evaluation of the nutritional value of d-amino acids previously reported. Nonessential amino acids were classified into four groups.
  1. Very useful nitrogen source: Glutamic acid, Aspartic acid

  2. Useful nitrogen source: Alanine, Diammonium citrate

  3. Insufficient nitrogen source: Glycine, Proline

  4. Harmful for chick growth: Serine

At the end of experiment chicks were killed and the concentration of free amino acids in the serum were measured. The concentration of glycine and serine in the serum increased when glycine was tested, but that of serine in the serum only increased when serine was tested. This result suggested the pathway from glycine to serine was fast and the opposite one was very slow.  相似文献   

17.
Gallic acid acts as a precursor molecule to synthesize various tannin molecules. These are plant polyphenols and were proved to be good anti-oxidant, anti-cancerous, anti-inflammatory, anti-microbial compounds. In order to fully exploit prominent biological activities of specific tannins and to develop tannin-based new medicines, it is necessary to obtain their pure preparations with an aim of high yield and specificity. In the present study, gallic acid is synthesized by the hydrolysis of tannic acid using a microbial based transformation process. The microorganism was isolated and identified. The ability of the isolated microorganism to covert tannic acid into gallic acid was determined by HPLC and enzyme production.
  • Highlights
  • The present investigation signifies the role of Enterobacter spp. in various processes:

  • ??To synthesize gallic acid (a precursor for food oxidant such as propyl gallate) and a bacteriostatic antibiotic (trimethoprim).

  • ??To protect the environment from tannery’s discharge through the process of biodegradation.

  • ??To reduce the toxicity of tannins in animal feed.

  相似文献   

18.
Inmunoglobulin isolated from human sera, be it by the cryo-alcohol, rivanol, multi membrane electrodecantation or polyethylene glycol process, alvays contains denatured material. This may result from the influence either singly or in combination, of acme of the follwing factors:
  1. inefficiency of the purification procedure;

  2. surface denaturation;

  3. imperfect freeze-drying of the final product; and

  4. factors yet unknown vhich cause alteration in the immoglobulins or other protein components not ellminated by the purification procedures.

  相似文献   

19.
Abstract

This study evaluated remediation of the herbicide sulfentrazone in soils with three different mineralogies (kaolinite, hematite, and gibbsite) and three remediation sulfentrazone treatments (Canavalia ensiformis L., Crotalaria juncea L., and natural attenuation). This study was conducted in a factorial scheme, in triplicate with randomized block design. Sulfentrazone was applied at 0 and 400?g ha?1. We analyzed sulfentrazone residue in the soils by high-performance liquid chromatography and confirmed the results with bioassays of Pennisetum glaucum. Herbicide movement was greater in the kaolinitic soil without plant species. The retention of herbicide in the kaolinitic soil occurred in larger quantities in the 0–12?cm layer, with higher levels found in the treatments with plants. In the hematitic soil with C. juncea, all applied herbicides were concentrated in the 0–12?cm layer. In the other hematitic soil treatments, sulfentrazone was not detected by chemical analysis at any soil depth, although in many treatments, it was detected in the bioassay. Phytoremediation was more efficient with C. ensiformis grown in gibbsitic soil, reducing the sulfentrazone load by approximately 27%. Natural attenuation was more efficient than phytoremediation in oxidic soils due to soil pH and texture soils favored microbial degradation of the compound.
  • Highlights
  • The influence of soil mineralogy of herbicide sulfentrazone retention was evaluated.

  • Canavalia ensiformis and Crotalaria juncea were evaluated as phytoremediation plants.

  • Kaolinite soils presented great movement of sulfentrazone in the soil.

  • Natural attenuation is more efficient in oxide soils than phytoremediation.

  相似文献   

20.
  1. Research into the visual shape discrimination abilities of compound‐eyed animals has almost exclusively been limited to insects, the crustaceans having been virtually ignored. The two groups have many dissimilarities, having primarily adapted in different habitats to different lifestyles. Differences may exist in visual systems and visually mediated behavior.

  2. Fiddler crabs (Uca pugilator), without training, differentially approached dissimilar silhouettes presented simultaneously, demonstrating visual discrimination between stationary, geometric shapes of equal‐area. The strength of response was ordered hierarchically: vertical rectangle, horizontal rectangle, triangle, square, circle.

  3. Basic geometric shapes were used to facilitate replication and comparison with research findings from other species.

  相似文献   

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