GROWTH DEPRESSING FACTORS IN RAPESEED OIL MEAL: V. THE EFFECTS OF MYROSINASE ACTIVITY ON THE TOXICITY OF THE MEAL

1963 ◽  
Vol 43 (1) ◽  
pp. 169-173 ◽  
Author(s):  
R. Belzile ◽  
J. M. Bell ◽  
L. R. Wetter
Keyword(s):  
Rapeseed Oil ◽  
Dry Matter ◽  
Water Soluble ◽  
Hot Water ◽  
Full Potential ◽  
Potential Toxicity ◽  
Growth Depression ◽  
Animal Feeding ◽  
Myrosinase Activity ◽  
Soluble Components

A study was made of the effects of adding 0.1 per cent myrosinase (a thioglucoside-splitting enzyme) to mouse diets containing Swedish or Polish type rapeseed oil meal and hot water-treated fractions of the meal. The latter were devoid of active enzyme but contained known quantities of the thioglucosides, precursors of the toxic isothiocyanates (I) and thiooxazolidones (T).Hot water extraction of the meals resulted in about 20 per cent of the dry matter being extracted and in significant alteration in the proportions and amounts of I and T.The addition of myrosinase to untreated rapeseed oil meals failed to increase the toxicity, presumably because there was already sufficient enzyme in the meals to reduce gains to about 25 per cent of normal. Addition of enzyme to the extracted residue (containing about one-third of the original thioglucosides of the meal) also failed to increase the toxicity. Enzyme addition to diets containing the water-soluble components resulted in significant growth depression but the full potential toxicity was not obtained.It is concluded that the enzyme myrosinase is an important factor affecting the toxicity of rapeseed oil meal in animal feeding, although conditions for its optimum activity were not achieved in this experiment where semi-purified enzyme was employed as a dietary supplement.

GROWTH-DEPRESSING FACTORS IN RAPESEED OIL MEAL: VII. EFFECTS OF MYROSINASE ACTIVITY ON TOXICITY FOLLOWING TREATMENT WITH BUFFERED SOLUTIONS

1966 ◽  
Vol 46 (3) ◽  
pp. 165-169 ◽  
Author(s):  
R. J. Belzile ◽  
J. M. Bell
Keyword(s):  
Enzyme Activity ◽  
Rapeseed Oil ◽  
Solution Treatment ◽  
Rapeseed Meal ◽  
Water Soluble ◽  
Potential Toxicity ◽  
Buffer Solution ◽  
Brassica Napus L ◽  
Buffer Solutions ◽  
Myrosinase Activity

Solvent-process, uncooked rapeseed meal of Brassica napus L. (summer) origin was autoclaved at 0.7 kg/cm2 to destroy myrosinase and compared with uncooked meal. Each type of meal was treated with buffer solutions at pH 3.0, 6.0, and 9.0 for 1 hour at temperatures of 22 °C and 50 °C. Unextracted meals were air-dried after buffer solution treatment; extracted meals were filtered under vacuum and washed twice with similar buffer solution before drying. The resulting meals were assayed chemically for isothiocyanate (I) and oxazolidinethione (O) and tested for toxicity with mice using diets containing up to 0.07% I+O.Treatment of myrosinase-free rapeseed meal at any pH resulted in no apparent change in toxicity provided the sample was not filtered. Extraction of soluble matter removed over 80% of the I+O, but growth was depressed on meal processed at pH 3.0. Some of the thioglucosides apparently were converted into other non-water-soluble compounds.Exposure of enzyme-active meal to buffer solutions without subsequent filtration resulted in a one-third reduction in I+O at pH 3.0, one-half reduction at pH 6.0, and two-thirds reduction at pH 9.0. Further losses occurred upon filtration but all of these meals contained significantly more I+O than did enzyme-free meals similarly processed. Chemically determined I and O may fail to measure the potential toxicity of rapeseed meals in which enzyme activity has occurred.

Contributions to the Analysis of Rubber. I. Determination of the Water-Soluble Components of Rubber

1937 ◽  
Vol 10 (3) ◽  
pp. 574-583
Author(s):  
P. Dekker
Keyword(s):  
Acetic Acid ◽  
Acid Reflux ◽  
Water Soluble ◽  
Hot Water ◽  
Water Bath ◽  
Vulcanized Rubber ◽  
Magnesium Compounds ◽  
Calcium Compounds ◽  
Soluble Components

Abstract 1. It is shown that the methods which are ordinarily used for determining water-soluble substances in raw rubber give low results, and are quite useless for vulcanized rubber. 2. New analytical procedures are developed for determining the water-soluble substances in raw rubber and in vulcanized rubber. These procedures are carried out in the following manner. (a) Raw Rubber.—Heat 2 grams of rubber in 80 cc. of xylene and 5 cc. of acetic acid on a water bath until the rubber is completely dissolved, add 5 cc. of acetic acid and 10 cc. of water, heat for 3–4 hours on the water bath with frequent agitation, transfer to a distilling flask (rinsing the first flask with 50 cc. of hot water), distill the xylene with steam, filter the residual solution, evaporate the filtrate on a water bath; and dry at 100° C. (b) Vulcanized Rubber and Rubber Mixtures.—First extract the sample with acetone, heat 2 grams of the acetone-extracted sample with 80 cc. of xylene on a water bath, add 5 cc. of acetic acid, reflux the mixture on an oil bath, after complete dissolution add 5 cc. of acetic acid and 10 cc. of water, heat the solution for 2 hours on an oil bath at 110–120° C., distill the xylene, as in the determination with raw rubber, filter the residue, evaporate the filtrate to dryness, take up the residue in 50 cc. of water, pass a current of hydrogen sulfide through the solution for 10 minutes to precipitate zinc as sulfide, filter, evaporate the filtrate, and dry the residue at 100° C. 3. In the presence of calcium compounds, magnesium compounds, glue and textiles, the method gives false results. Modifications of the method are therefore recommended, whereby these substances are eliminated.

Evaluation of different extractants for the estimation of bioavailable selenium in seleniferous soils of Northwest India

Soil Research ◽  
2005 ◽  
Vol 43 (5) ◽  
pp. 639 ◽  
Author(s):  
K. S. Dhillon ◽  
Neeraj Rani ◽  
S. K. Dhillon
Keyword(s):  
Dry Matter ◽  
Oryza Sativa L ◽  
Selenium Concentration ◽  
Triticum Aestivum L ◽  
Water Soluble ◽  
Hot Water ◽  
Western India ◽  
Significant Relationships ◽  
Northwest India ◽  
North Western

Efficacy of various extractants—AB-DTPA, 0.5 m Na2CO3, 0.25 m KCl, 0.1 m KH2PO4, hot water, and isotopically exchangeable selenium (Se)—was studied for estimating bioavailable Se in 15 naturally occurring alkaline seleniferous soils in north-western India. Total Se concentration in these soils varied from 0.6 to 3.1 µg/g. Amount of Se extracted as isotopically exchangeable was the greatest, and that extracted with 0.5 m Na2CO3 was the smallest. When grown in the seleniferous soils, raya (Brassica juncea) accumulated (μg Se/g dry matter) 1.5–86.6, wheat (Triticum aestivum L.) 0.7–58.3, maize (Zea mays L.) 1.7–8.6, and rice (Oryza sativa L.) 1.5–4.6. Raya, wheat, and maize plants absorbed Se more than the maximum permissible level for animal consumption (5 μg Se/g dry matter) in 9, 8, and 4 experimental soils, respectively. Selenium concentration of maize was significantly correlated with the amount of Se extracted by 0.25 m KCl (r = 0.646,P < 0.01), 0.1 m KH2PO4 (r = 0.498,P < 0.10), and with total Se concentration (r = 0.628,P < 0.05) of the soils; Se concentration in rice was correlated with AB-DTPA extractable Se (r = 0.443,P < 0.10). Highly significant relationships between hot water soluble Se and concentration of Se in raya (r = 0.705,P < 0.01), wheat (r = 0.696,P < 0.01), maize (r = 0.698,P < 0.01), and rice (r = 0.559,P < 0.05) suggest that it can reliably quantify bioavailable Se in seleniferous soils of north-western India. Hot water soluble Se was positively correlated with electrical conductivity (r = 0.514,P < 0.05), total Se concentration (r = 0.710,P < 0.01), and KCl-extractable Se (r = 0.712,P < 0.01) of the soils.

The question of grain content and forage quality in maize: comparisons between isogenic fertile and sterile plants

1975 ◽  
Vol 85 (3) ◽  
pp. 455-463 ◽  
Author(s):  
E. S. Bunting
Keyword(s):  
Dry Matter ◽  
Water Soluble ◽  
Hot Water ◽  
Soluble Carbohydrates ◽  
Maize Breeding ◽  
Forage Maize ◽  
Yield And Quality ◽  
Crop Development ◽  
Grain Formation

SUMMARYResults are presented from four experiments in which comparisons were made between isogenic sterile and fertile plants of maize to study the effects of grain content on yield and quality of shoot dry matter. In two experiments comparisons were made over a range of densities, extending from 5 to 25 plants/m2 in 1972 and 5 to 20 plants/m2 in 1973. The other two experiments, grown in 1974 at a density of 10 plants/m2, were sampled 30, 60 and 90 days after flowering.In 1972 and 1973 yield of shoot dry material was about 10% higher in fertile plants at the lowest density, 5 plants/m2, but grain formation had a negligible effect at higher densities. In 1974, at 10 plants/m2, the yield advantage for fertile plants was 6–7%. These results are in line with other European data, but show a much smaller effect of grain formation on shoot dry matter yield than is normally recorded in USA trials. The discrepancies probably reflect differences in environmental conditions.Absence of grain had little effect on contents of nitrogen, ash and in vitro digestible dry matter, and increased content of pepsin soluble material and hot water soluble carbohydrates. Percentage content of dry matter in the shoot was higher in fertile plants in 1973, and during the later stages of crop development in 1974.The results suggest that the importance attached to high grain content as an essential requirement for yield and quality in forage maize is exaggerated, and that the restriction of maize breeding and testing programmes to assessments of grain production, in the belief that the best grain varieties will also be best for forage, can no longer be justified in northern European countries.

Yield and quality components in maize grown for silage

1968 ◽  
Vol 71 (3) ◽  
pp. 393-403 ◽  
Author(s):  
A. J. Thomson ◽  
H. H. Rogers
Keyword(s):  
Crop Yield ◽  
Dry Matter ◽  
Crop Yields ◽  
Matter Content ◽  
Water Soluble ◽  
Soluble Carbohydrates ◽  
Soluble Carbohydrate ◽  
Dry Matter Content ◽  
Maize Varieties ◽  
Soluble Components

SUMMARYResults from three trials are presented. The main variables were date of harvest, plant density and variety. Measurements were made of whole-crop yields and yields from plant fractions (leaf, stem, cob). Quality components—digestibility, acid-pepsin solubility, water-soluble carbohydrates, nitrogen and ash—were estimated for whole crop and fractions. There were successive samplings for quality components.Whole-crop yield from fractions and yield of quality components increased with density. Whole-crop yield differed significantly with harvesting date as did all fractions except cob, although the proportion of cob increased with time. The earlier harvesting date gave greater yields of quality components.There was no effect of density on the dry-matter content but later harvesting resulted in higher dry matter.The only quality component affected by density was nitrogen content but there were large effects of harvesting date on digestibility and the acid-pepsin components.Regressions were computed for quality components on dry-matter proportion of cob and the dry-matter content of the whole crop. Regressions were significant for the acid-pepsin soluble components and the water-soluble carbohydrate component on the proportion of cob. Regressions of digestibility and pepsin-soluble components (total and organic) on dry-matter content were significant.The implications of these findings to the breeding of maize varieties are discussed.

Characterisation of hot-water-soluble components of starches

1993 ◽  
Vol 242 ◽  
pp. 203-215 ◽  
Author(s):  
Gurunathan Murugesan ◽  
Kiyoshi Shibanuma ◽  
Susumu Hizukuri
Keyword(s):  
Water Soluble ◽  
Hot Water ◽  
Soluble Components

Extraction and characterization of polysaccharides from Mesembryanthemum crystallinum

e-Polymers ◽  
2005 ◽  
Vol 5 (1) ◽  
Author(s):  
Nour H. M’sakni ◽  
Hamouda Zayane ◽  
Hatem Majdoub ◽  
Claudine Morvan ◽  
Sadok Roudesli ◽  
...  
Keyword(s):  
Chemical Structure ◽  
Dry Matter ◽  
Molar Mass ◽  
Extraction Process ◽  
Water Soluble ◽  
Hot Water ◽  
Sugar Composition ◽  
Rhamnogalacturonan I ◽  
Partial Degradation

AbstractWater-soluble polysaccharides were isolated from Mesembryanthemumcrystallinum. Two methods were applied, based (i) on the extraction in hot water (for fresh and dry plants, FP and DP) and (ii) on freeze-thawing of fresh plants (FT). Each fraction was purified by precipitation in ethanol followed by ultrafiltration of recovered solids dissolved in water through a membrane with a molecular weight cut off of 100 000. Elemental analysis demonstrated that the extracted products were polysaccharides exempt from proteins. The yield relative to the corresponding dry matter varied from 1.6 to 3% depending on the starting sample and the extraction process. Obtained products were characterised by their structural (sugar composition, degree of methylation (DM) and acetylation, molar mass of acid equivalent unit) and macromolecular characteristics (molar mass and intrinsic viscosity). A galacturonic-acid content larger than 65% and a DM value of c. 40% showed that the isolated polysaccharides belong to the fairly methylated pectin class. FP and FT structures consisted of the two blocks homogalacturonan (HG) and rhamnogalacturonan-I (RG-I) with relative proportions of 62 - 68% and 29 - 34%, respectively. They showed very similar physicochemical behaviour. On the other hand, DP exhibited significant differences in the chemical structure (50% HG and 46% RG-I blocks) and physical properties, indicating that partial degradation of HG moieties occurred during plant drying.

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